Skip to main content
NCBI home page
Food Chemistry: X logoLink to Food Chemistry: X
. 2026 Mar 17;35:103766. doi: 10.1016/j.fochx.2026.103766

Photostability and antimicrobial performance of natural yellow pigments in food systems: Insights into light-induced degradation and functional consequences

Lei Zhao a,b,c,⁎,1,2, Ya Zhou d,1, Weiguo Yue b, Chen Yuan b, Lifang Zhang b, Renyong Zhao a,⁎
PMCID: PMC13068607  PMID: 41971407

Abstract

Natural yellow pigments such as bisdemethoxycurcumin (BDMC), curcumin (Cur), and geniposide are increasingly investigated as clean-label antimicrobial agents due to their reactive oxygen species (ROS)-mediated activity. However, their performance in food systems is often limited by photodegradation under visible light, particularly in refrigerated and transparent-packaged products. This review summarizes current understanding of the structure-dependent photochemical behavior, degradation pathways, and ROS-driven antibacterial mechanisms of representative yellow pigments. Evidence shows that extended π-conjugation and β-diketone structures enhance photo-reactivity but also accelerate photodegradation, leading to reduced antimicrobial efficacy. BDMC and Cur display strong ROS-mediated activity but limited light stability, whereas geniposide exhibits higher photostability but weaker intrinsic antibacterial activity. These findings highlight a trade-off between oxidative reactivity and light stability. Strategies such as light-shielding packaging and nanoencapsulation are discussed to improve pigment stability and antimicrobial performance in illuminated food systems.

Keywords: Natural yellow pigment, Bisdemethoxycurcumin, Photodegradation, Reactive oxygen species, Antimicrobial activity, Food packaging

Graphical abstract

Unlabelled Image

Open in a new tab

Highlights

  • •

    Structure–photostability–function relationships of natural yellow pigments are clarified.

  • •

    Curcumin, BDMC, and geniposide show distinct light stability profiles.

  • •

    CIELAB color changes quantitatively indicate pigment degradation.

  • •

    ROS generation and membrane disruption drive antibacterial activity.

  • •

    Encapsulation and light-filtering films improve pigment retention.

1. Introduction

Natural yellow pigments have gained widespread attention in food applications not only for their coloring properties but also for their antimicrobial and antioxidant potential. Representative compounds such as Cur, BDMC, and geniposide have been investigated for their broad-spectrum antibacterial efficacy and favorable safety profiles. These attributes align well with the rising demand for clean-label preservation approaches in minimally processed food products (Chauhan & Rao, 2024).

Despite their bioactivity, the practical application of these pigments in transparent-packaged and light-exposed foods is constrained by their pronounced sensitivity to light. Many natural yellow pigments are photolabile and undergo structural degradation upon exposure to visible light, which compromises their antimicrobial performance and visual stability (Zhang et al., 2024).

Among these compounds, BDMC stands out for its ability to generate intracellular ROS, which induce oxidative stress and disrupt bacterial membranes. However, prolonged light exposure significantly attenuates this mechanism by altering the chromophoric β-diketone moiety, leading to reduced ROS generation and weakened antimicrobial efficacy. Experimental data show that the minimum inhibitory concentration (MIC) of BDMC against E. coli increases more than eightfold after extended illumination (Damrongrungruang et al., 2023).

In contrast, iridoid-type pigments such as geniposide exhibit high photostability owing to their saturated ring structures and lack of extensive conjugation. Geniposide remains largely intact under visible light exposure but demonstrates inherently weaker antibacterial activity, mainly through membrane interaction rather than ROS generation (Ahmed et al., 2024).

In light of these constraints, there is a pressing need to bridge the gap between pigment photostability and functional antimicrobial performance in real food systems. While previous studies and reviews have examined individual aspects such as photochemical degradation mechanisms, antioxidant properties, or delivery approaches (Negi, 2025), a systematic integration linking degradation kinetics, ROS-mediated antimicrobial function, and packaging-level stabilization strategies remains limited, particularly from an application-oriented perspective (Guo et al., 2024).

In illuminated food environments, pigment performance is governed not only by intrinsic molecular stability but also by the interaction between chemical structure, light exposure conditions, and packaging design (Devi et al., 2025). This interaction creates a critical stability–efficacy trade-off, where photodegradation directly translates into functional decline during storage and display (Wijesekara & Xu, 2024).

To address this gap, this review integrates structural photoreactivity, degradation pathways, ROS-driven antibacterial mechanisms, and packaging-based stabilization strategies across representative phenolic-derived yellow pigments, including BDMC, Cur, and geniposide.

By establishing a structure–function–stability framework, this work provides a translational perspective for selecting, stabilizing, and implementing natural yellow pigments in illuminated food systems, thereby extending current knowledge from mechanistic understanding toward application-oriented design. This review focuses on phenolic-derived yellow pigments rather than carotenoid-based pigments, as these two classes differ substantially in photoreactivity and antimicrobial behavior.

2. Structural and Photoreactive characteristics of natural yellow pigments

The structural characteristics of natural yellow pigments play a decisive role in determining their behavior under light exposure and their subsequent antimicrobial performance. In food preservation systems where transparent or semipermeable packaging is common, understanding these structural distinctions is critical for predicting pigment stability and functionality.

Among food-grade yellow pigments, curcuminoids and iridoid glycosides are widely studied due to their coloring properties and biological activities. Cur, the major component in turmeric, is a diarylheptanoid composed of two methoxy- and hydroxyl-substituted aromatic rings connected by a conjugated β-diketone chain. This extended conjugation provides strong light absorption but renders the molecule highly susceptible to photodegradation under visible light, often leading to structural breakdown and reduced antibacterial efficacy (Tahay et al., 2022). In comparison, BDMC lacks the methoxy substituents but retains the β-diketone core. This structural simplification confers slightly higher photostability while preserving ROS-generating ability and membrane-disruptive antibacterial mechanisms (Zhang, 2022). BDMC is also the predominant curcuminoid found in yam-derived pigment fractions (Zhao et al., 2020). Compared with curcumin, BDMC has been reported to exhibit slower photodegradation kinetics and longer apparent half-life under comparable illumination conditions, reflecting its relatively improved photostability among curcuminoid pigments (Kim et al., 2025).

On the other hand, geniposide, an iridoid glycoside derived from Gardenia jasminoides, features a cyclopentapyran ring and a glucose moiety. Unlike curcuminoids, it lacks extended π-conjugation, and its absorbance lies predominantly in the UVB region (Ghosh & Sarkar, 2024). As a result, geniposide demonstrates exceptional photostability under visible light but exhibits relatively weak antimicrobial activity, typically not mediated by ROS pathways (Ahmed et al., 2024). However, geniposide exhibits relatively weak antimicrobial activity and its effects are typically not mediated through ROS pathways.

2.1. Structural features and their implications for light reactivity

The chromophoric architecture of these pigments largely determines their light sensitivity. Cur possesses both methoxy and hydroxyl groups on its aromatic rings, with a central β-diketone moiety acting as the primary site of photo-induced degradation. Under illumination, it undergoes rapid bond cleavage and oxidative fragmentation, leading to inactive phenolic products (Bērziņa & Mieriņa, 2023). BDMC, while retaining the conjugated backbone, exhibits slightly improved resistance to photodegradation, likely due to the absence of methoxy groups that increase electron density and photoreactivity (Ahmad et al., 2024).

In contrast, geniposide lacks such chromophores. Its structure is dominated by saturated carbon rings and glycosidic linkages, making it more stable under light but limiting its ability to initiate oxidative stress through ROS. Its stability is advantageous for long-term storage but restricts its application where rapid antimicrobial action is required (Gao et al., 2025).

The structural features of these representative yellow pigments—Cur, BDMC, and geniposide—are illustrated in Fig. 1, highlighting key differences in conjugation systems, chromophoric groups, and glycosidic linkages that influence their photoreactivity and stability.

Fig. 1.

Fig. 1

Open in a new tab

Chemical structures of representative natural yellow pigments. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.)

Curcumin (Cur, A), bisdemethoxycurcumin (BDMC, B), and geniposide (C) represent structurally distinct yellow pigments commonly used in food systems. Cur and BDMC belong to the curcuminoid family and contain a conjugated β-diketone system associated with visible-light absorption and photoreactivity. In contrast, geniposide is an iridoid glycoside lacking an extended conjugated chromophore, which contributes to its higher stability under visible light.

2.2. Photodegradation behavior and functional implications

Photodegradation of these pigments is typically modeled as a first-order kinetic process. Under continuous 460 nm blue LED irradiation (irradiance ca. 10 W/m2) at ambient temperature (≈ 25 °C) in a standardized photostability setup, BDMC exhibits a degradation rate constant of k = 0.0237 h−1, corresponding to a half-life of approximately 29.2 h—longer than that of curcumin (t₁/₂ ≈ 15 h) and chlorophyllin (t₁/₂ < 8 h) under similar conditions. Degradation kinetics were quantified by HPLC analysis of residual pigment concentration over time. This nominal irradiation intensity is widely used in photodegradation studies to approximate common visible light exposures such as retail display lighting (Kim et al., 2025).

Mechanistic analysis reveals that BDMC degradation is initiated through excitation of the conjugated π-system, followed by cleavage of the β-diketone linkage. This leads to the formation of intermediate products such as C₁₉H₁₈O₃ and C₁₉H₁₆O₃, which have been reported in previous studies based on liquid chromatography–mass spectrometry (LC–MS) analysis and structural characterization. These products lack the full chromophore structure required for ROS generation (Zhao et al., 2020). These products accumulate over time and correlate with a measurable reduction in antibacterial efficacy, as shown later in Section 3.2.

In contrast, geniposide remains largely intact under comparable light conditions. High-Performance Liquid Chromatography (HPLC) and Liquid Chromatography–Mass Spectrometry (LC–MS) analyses reveal no significant degradation products after prolonged exposure to 460 nm illumination, underscoring its photostable nature (Shi et al., 2018). However, this stability does not translate to strong antimicrobial activity, particularly against Gram-negative bacteria such as E. coli.

2.3. Conclusion and transition

In summary, Cur and BDMC share similar structural frameworks, but BDMC offers a more favorable balance between photostability and bioactivity. Geniposide, while photostable, exhibits limited antimicrobial effectiveness. These structural distinctions form the mechanistic basis for differences in degradation behavior and functional decline under light exposure. The next section explores the kinetics of this degradation process and how it compromises ROS-mediated antibacterial mechanisms.

3. Photodegradation behavior and light sensitivity of BDMC

The structural integrity of natural yellow pigments is a key determinant of their biological activity, particularly under conditions involving light exposure. Among them, BDMC has attracted growing interest due to its dual role as a pigment and a bioactive antimicrobial agent. However, like many polyphenolic compounds with extended conjugation systems, BDMC is vulnerable to photochemical degradation when exposed to visible light, which can lead to significant alterations in its functional performance (Zhang, 2022).

3.1. Photodegradation kinetics of BDMC

The photostability of natural yellow pigments plays a decisive role in determining their functional longevity in food preservation systems. Among these, BDMC, a principal curcuminoid component in yam-derived pigments, exhibits a moderately stable response to blue light exposure. When subjected to continuous 460 nm LED illumination—conditions simulating transparent packaging or cold-chain storage—BDMC follows a first-order degradation model with a rate constant (k) of 0.0237 h−1 and a half-life (t₁/₂) of approximately 29.2 h (Komonsing et al., 2022). This degradation profile reflects a balance between chromophoric conjugation and structural resilience, placing BDMC between highly unstable Cur (t₁/₂ ≈ 15 h) and more photostable compounds such as geniposide, which undergoes minimal structural alteration under similar light intensities (Janga et al., 2018).

Photodegradation of BDMC is initiated by visible-light-induced excitation of its conjugated π-system, followed by bond cleavage and oxidative transformation within the β-diketone moiety (Gangemi et al., 2025). Such structural disruptions diminish both spectral absorbance and functional bioactivity, particularly its ability to mediate ROS generation—a key antibacterial mechanism discussed in later sections. The kinetic model also supports a predictable degradation trajectory, which is of practical value when estimating shelf life or planning light-shielding formulations (Su et al., 2021).

The observed half-life suggests that BDMC retains partial activity during short-term display or limited exposure but becomes significantly compromised over extended durations. In realistic food-packaging environments—such as retail lighting (fluorescent/LED at ∼500–1000 lx) or illuminated refrigeration units—this degradation process may occur more rapidly due to higher cumulative light doses and thermal acceleration (Melo et al., 2024). The consequence is not merely pigment fading but a quantifiable reduction in antimicrobial efficacy, as confirmed by subsequent mechanistic assessments.

Photodegradation behavior of BDMC under visible light exposure.

Representative HPLC chromatograms (410 nm) illustrate the time-dependent degradation of BDMC (retention time: 20.9 min) and the concurrent emergence of two primary photoproducts—C₁₉H₁₈O₃ (11.6 min) and C₁₉H₁₆O₃ (13.2 min)—under continuous 460 nm LED illumination for 45 h. A progressive reduction in BDMC peak area is observed over time (p < 0.001), accompanied by a corresponding increase in intermediate product peaks. Notably, photoproduct accumulation reaches a quasi-steady state after approximately 27 h, suggesting a dynamic balance between formation and secondary transformation processes. The overall decay profile is consistent with first-order kinetic behavior, supporting a time-dependent loss of chromophore integrity under visible light exposure. Reproduced from Zhao et al., 2020, with permission.

These findings underscore the importance of integrating photostability data into early-stage antimicrobial screening, particularly when selecting candidate pigments for transparent or semipermeable food packaging. Without such consideration, promising antimicrobial agents may underperform in real-world storage conditions, leading to functional inconsistency and potential food safety risks. Model-based degradation kinetics and endpoint retention comparisons are provided in Supplementary Figure A for conceptual illustration.

3.2. HPLC profiles and identification of BDMC degradation products

To elucidate the photodegradation pathway of BDMC, HPLC analysis was performed over a 45-h light exposure period under 460 nm LED illumination. As shown in Fig. 2, the initial chromatogram (0 h) displayed a single prominent peak at 21.0 min corresponding to BDMC. With increasing illumination time, two new peaks emerged at 12.5 min and 14.8 min, indicating the formation of photodegradation products.

Fig. 2.

Fig. 2

Open in a new tab

Photodegradation behavior of BDMC under visible light exposure.

As shown in Fig. 2, BDMC degradation proceeds in a time-dependent manner, with a rapid decline during the initial exposure period followed by a gradual attenuation phase. The emergence of intermediate peaks prior to their stabilization suggests sequential phototransformation rather than instantaneous cleavage. The plateau behavior observed after approximately 27 h indicates that the system approaches a pseudo-equilibrium state, in which intermediate formation and further degradation occur simultaneously. This kinetic profile reinforces the susceptibility of the β-diketone-conjugated chromophore to visible light excitation and provides mechanistic context for the subsequent decline in antibacterial performance discussed in Section 4.

Quantitative changes in peak intensity revealed a time-dependent decline in BDMC concentration, consistent with first-order degradation kinetics described in Section 3.1. The two major degradation products—putatively identified by Liquid Chromatography–Mass Spectrometry (LC-MS) as C₁₉H₁₈O₃ and C₁₉H₁₆O₃—showed progressive accumulation from 9 h to 27 h, after which their levels plateaued, suggesting stabilization of the degradation system. This kinetic pattern indicates that BDMC undergoes a stepwise oxidative transformation under visible light, primarily involving demethylation and hydroxylation reactions at the phenolic moieties.

The formation of these intermediates is particularly relevant to the pigment's functional behavior. Both C₁₉H₁₈O₃ and C₁₉H₁₆O₃ retain the conjugated aromatic core but lack the intact β-diketone structure, a key site for ROS generation. Consequently, their accumulation is associated with a marked decrease in antibacterial efficacy, as further discussed in Section 4. Notably, no further degradation into small molecular byproducts was observed up to 45 h, indicating that these intermediates are relatively stable under the given illumination conditions (Seidi Damyeh et al., 2020).

These findings highlight the need for structural preservation of BDMC in food systems requiring light exposure, such as transparent-packaged products. The HPLC profile provides direct evidence of pigment instability and supports the rationale for protective formulation strategies to maintain bioactivity over storage time.

3.3. Structural elucidation of BDMC Photodegradation products

The structural transformation of BDMC under light exposure was further investigated using HPLC–MS. Two major photoproducts, corresponding to the peaks observed at 12.5 min and 14.8 min in the HPLC chromatograms, were identified as C₁₉H₁₈O₃ (m/z = 294.12) and C₁₉H₁₆O₃ (m/z = 292.10), respectively (Zhao, 2020). These compounds share the aromatic backbone of BDMC but lack the complete β-diketone system, indicating that cleavage and oxidation occur primarily at the central heptadienone chain (Roney et al., 2025).

Based on MS fragmentation patterns and comparative analysis with known degradation pathways of curcuminoids, C₁₉H₁₈O₃ is presumed to form via hydroxylation at the terminal methylene, while C₁₉H₁₆O₃ arises through sequential dehydrogenation. This transformation pattern aligns with previous reports on visible-light-induced demethoxylation and keto–enol tautomer disruption in related structures (Chatterjee et al., 2024). Notably, both compounds exhibit reduced conjugation length compared to native BDMC, leading to a hypsochromic shift in absorbance and a loss in photodynamic efficiency.

The degradation of BDMC follows a first-order kinetic pattern, characterized by a progressive decline in BDMC levels and a concurrent accumulation of intermediate products (C₁₉H₁₈O₃ and C₁₉H₁₆O₃), which reach a plateau after approximately 27 h (Fig. 2) (Zhao, 2020). Importantly, ROS fluorescence assays performed during photodegradation indicate a progressive decline in overall ROS generation relative to intact BDMC. This observation is consistent with the formation of photoproducts that exhibit reduced conjugation; however, the ROS-generating capacity of individual intermediates has not yet been directly established (Zhao et al., 2025).

From a mechanistic standpoint, the β-diketone moiety plays a critical role in the photoexcitation and energy transfer processes essential for antibacterial ROS production. Its disruption through light-induced cleavage severely compromises the molecule's ability to interact with bacterial membranes or nucleic acids (Wolnicka-Glubisz & Wisniewska-Becker, 2023). This underscores the functional importance of maintaining the integrity of key chromophoric groups during storage and application in food systems.

Collectively, these structural insights bridge the chemical changes observed in HPLC/MS analysis with the biological consequences examined in later sections. They further support the design of targeted stabilization strategies, such as encapsulation or packaging modifications, to preserve the antimicrobial function of BDMC during practical use.

Structurally, the photoproducts C₁₉H₁₈O₃ and C₁₉H₁₆O₃ retain the aromatic backbone of BDMC but lack the β-diketone moiety—an essential chromophore for photoinduced ROS generation. This loss critically impairs their capacity to initiate oxidative stress in bacterial cells (Kim et al., 2025).

Consequently, these degradation products demonstrate significantly diminished antibacterial activity. Experimental MIC testing confirmed that photodegraded BDMC requires substantially higher concentrations to inhibit E. coli growth, reflecting a marked decline in antibacterial potency following light exposure (Supplementary Figure C). Rather than focusing on numerical shifts alone, the key observation is that degradation of the β-diketone-conjugated chromophore significantly reduces ROS-generating capacity, thereby diminishing membrane disruption and antibacterial efficacy. These findings establish a mechanistic link between BDMC photodegradation and functional decline.

3.4. Comparative Photodegradation behavior of cur, BDMC, and Geniposide under visible light

Cur and geniposide are structurally distinct yellow pigments belonging to different chemical families, exhibiting markedly different photochemical behaviors. Their comparative degradation characteristics under light exposure provide critical context for evaluating the practical application of BDMC in food systems.

Cur, a well-known curcuminoid, is structurally similar to BDMC but contains two additional methoxy groups at the ortho positions of its aromatic rings. These substituents slightly increase its chromophoric conjugation, rendering Cur even more photosensitive than BDMC. Under visible light (e.g., 460 nm), Cur undergoes rapid photodegradation, with reported half-lives ranging from 6 to 12 h depending on light intensity and solvent polarity (Pramana et al., 2024). The degradation typically follows a first-order kinetic model, involving the cleavage of the β-diketone linkage and oxidative fragmentation, which leads to the formation of vanillin, ferulic acid, and other small phenolic derivatives (Pramana et al., 2024). These products lack the ability to generate ROS, resulting in a marked reduction in antimicrobial activity. In fact, previous studies have shown that light-exposed Cur loses over 80% of its bactericidal effect against E. coli and S. aureus within 12 h of storage under standard illumination (Yuan et al., 2022).

In contrast, geniposide—a glycosylated iridoid compound derived from Gardenia jasminoides—exhibits exceptional photostability. Its molecular structure lacks extended π-conjugation and photoactive carbonyl systems, which minimizes its reactivity under visible light (Li et al., 2025). The absorption maximum of geniposide falls primarily in the UVB range (λ_max ≈ 238 nm), well outside typical LED or ambient lighting conditions used in food storage (Chen et al., 2020). Consequently, geniposide remains structurally intact even after prolonged exposure, with no significant breakdown products detectable by HPLC or LC–MS under simulated storage illumination. However, this structural resilience comes at a cost: geniposide exhibits only mild antimicrobial activity, primarily through non-ROS-dependent pathways such as enzyme inhibition or membrane interaction (Yang, Cai, et al., 2025).

Geniposide exhibits markedly higher photostability under visible light exposure, largely due to its non-extended conjugation system and absence of β-diketone moieties. However, this structural stability is accompanied by limited photo-induced reactivity and reduced ROS generation capacity(Sobolewska et al., 2025). As a result, although geniposide maintains chromatic integrity during storage, its antimicrobial potency remains comparatively weak under illumination (Jin et al., 2023). This contrast highlights a critical stability–efficacy trade-off, in which molecular features that enhance structural robustness may simultaneously limit functional antibacterial performance.

Together, these comparisons delineate a functional spectrum among yellow pigments. Cur degrades too rapidly to retain its antimicrobial potential in illuminated applications. Geniposide, though stable, lacks the potent ROS-driven antibacterial efficacy of BDMC. BDMC occupies a unique middle ground: it retains moderate photostability while exhibiting robust ROS-mediated activity, making it a more promising candidate for controlled photodynamic applications in food systems—provided its degradation kinetics are properly managed. The contrasting photochemical behaviors of Cur and geniposide underscore the need for pigment-specific functional evaluations. While Cur rapidly degrades into inactive phenolics such as vanillin and ferulic acid, geniposide resists photodegradation but lacks ROS-mediated efficacy.

A simulated comparison of MIC values for these pigments and their primary photoproducts (e.g., C₁₉H₁₈O₃, vanillin) demonstrates a consistent trend: degradation leads to marked antimicrobial activity loss (Supplementary Figure B). These simulations support the rationale that ROS-generating pigments lose efficacy upon photochemical breakdown, even before direct experimental verification. These values were extrapolated from previously reported MIC ranges for curcuminoid and iridoid derivatives (Górski et al., 2022; Muchtaromah et al., 2020; Xu et al., 2024; Yenigun et al., 2024) and illustrate relative trends rather than absolute thresholds.

4. Impact on antibacterial mechanisms

Given that photodegradation leads to chemical modifications, it is critical to assess how these structural changes impact the key antibacterial mechanisms of natural pigments. The antibacterial activity of natural yellow pigments—particularly BDMC—is closely related to their ability to induce intracellular oxidative stress and disrupt bacterial membranes under light exposure. However, photodegradation significantly modulates these mechanisms by altering the chemical structure and functional reactivity of the pigments.

BDMC functions as a photosensitizer that efficiently generates ROS, which trigger lipid peroxidation and membrane destabilization in Escherichia coli. With increasing concentrations of BDMC under 460 nm illumination, fluorescence microscopy images using Propidium Iodide (PI) staining clearly show enhanced membrane damage, evidenced by stronger red fluorescence signals (Fig. 3A). The quantitative fluorescence intensity (Fig. 3B) reveals a dose-dependent increase in membrane permeability, with statistically significant differences observed between concentrations above 10 mg/mL (p < 0.05). These results confirm that membrane integrity disruption is a key mechanism underlying BDMC's antimicrobial effect.

Fig. 3.

Fig. 3

Open in a new tab

ROS generation and membrane damage induced by BDMC in Escherichia coli. (A) Fluorescence microscopy images of PI-stained E. coli cells exposed to BDMC (0–40 μg/mL) under blue light. Increasing fluorescence intensity reflects enhanced membrane permeability. (B) Quantitative analysis of red fluorescence intensity (RFU), showing a dose-dependent increase, with significant differences above 10 μg/mL (p < 0.05). (C) Intracellular ROS levels measured by DCFH-DA assay indicate a sharp increase in oxidative stress beyond the MIC. H₂O₂ served as a positive control. Data are expressed as mean ± SD (n = 3). Different letters indicate significant differences (ANOVA, p < 0.05). Representative unpublished experimental data generated by the authors.

As discussed in Section 3, light-induced degradation of BDMC leads to the breakdown of its β-diketone moiety, a critical chromophore for ROS generation. This structural alteration results in diminished oxidative stress induction and membrane disruption.

Experimental results confirmed this functional decline: MIC of BDMC against E. coli increased from 10 μg/mL to 85.3 μg/mL after 460 nm illumination, reflecting an over eightfold loss in antibacterial potency (Supplementary Figure C).

This evidence directly supports the hypothesis that photodegradation compromises BDMC's photosensitizing ability and ROS-based antimicrobial mechanism. It also validates the degradation model proposed in Fig. 2 and the ROS activity profile shown in Fig. 3.

These findings collectively highlight a dual-mode antibacterial mechanism of BDMC, involving both ROS-mediated oxidative stress and physical membrane permeabilization (Aminnezhad et al., 2023). However, as discussed in Section 3.2, prolonged illumination leads to photodegradation of BDMC's β-diketone chromophore—a critical structural feature responsible for its photoactivation. This structural degradation significantly compromises BDMC's capacity to generate ROS and disrupt bacterial membranes under subsequent light exposure (Zhang, Su, et al., 2023). While total ROS production increases during the illumination period due to intact BDMC activity, the resulting photoproducts (e.g., C₁₉H₁₈O₃, C₁₉H₁₆O₃) lack conjugated systems and are unable to initiate further ROS formation (Kah et al., 2023). Consequently, this loss of photoreactivity and membrane interaction correlates with a marked rise in MIC values observed post-illumination.

While total ROS levels were measured via the 2′,7’-Dichlorodihydrofluorescein diacetate (DCFH-DA) assay, this probe is nonspecific and cannot distinguish among different reactive oxygen species. In fact, various ROS—including singlet oxygen (1O₂), superoxide anion (·O₂−), and hydroxyl radicals (·OH)—may contribute differently to bacterial damage mechanisms. Each species exhibits distinct reactivity profiles and cellular targets: for instance, 1O₂ primarily oxidizes membrane lipids, while ·OH can damage nucleic acids and proteins (Singh et al., 2023). Advanced analytical techniques, such as electron spin resonance (ESR) spectroscopy and species-specific fluorescence probes (e.g., SOSG for 1O₂, HPF for ·OH, and DHE for ·O₂−), offer greater resolution and should be employed in future work to elucidate ROS-specific contributions to pigment-mediated antimicrobial activity (Wang et al., 2023). From a mechanistic standpoint, the degradation-induced decline in antimicrobial capacity can thus be attributed to impaired ROS generation and weakened interaction with bacterial membranes. These findings emphasize the importance of structural preservation when applying light-sensitive pigments in antimicrobial food systems. While general ROS levels were measured via DCFH-DA fluorescence, future studies should differentiate among specific species—such as ·O₂−, ·OH, and 1O₂—through ESR or probe-specific fluorescence techniques. These distinctions would deepen the mechanistic understanding of pigment-induced oxidative stress. Notably, differences in pigment-induced antimicrobial mechanisms have been observed between Gram-negative and Gram-positive bacteria. Gram-negative bacteria such as Escherichia coli possess an outer membrane containing lipopolysaccharides that may limit pigment penetration, whereas Gram-positive bacteria such as Staphylococcus aureus lack this outer membrane but contain a thicker peptidoglycan layer, which can influence ROS diffusion and oxidative stress responses. For instance, BDMC exhibits distinct ROS induction patterns and membrane interaction behaviors in Staphylococcus aureus (Gram-positive), potentially due to differences in cell wall composition and oxidative stress response systems (Zhang, Zhao, et al., 2023). While this review focuses primarily on E. coli, future work should incorporate broader pathogen panels to evaluate pigment selectivity and mechanism variability across bacterial types.

This mechanism is visually summarized in Fig. 4, which illustrates the sequential loss of antibacterial function following BDMC photodegradation. The depicted intermediates represent proposed structural outcomes reported or inferred from previous photodegradation studies. To better illustrate the structural basis of functional decline, the degradation pathway and resulting structural changes are schematically summarized in Fig. 4. (See Fig. 5.)

Fig. 4.

Fig. 4

Open in a new tab

Structural transformation of BDMC under visible light and its impact on antimicrobial function.

Fig. 5.

Fig. 5

Open in a new tab

Influence of packaging strategies on BDMC stability and antimicrobial performance.

Schematic illustration of BDMC photodegradation under visible light. Cleavage of the β-diketone chromophore leads to the formation of proposed degradation intermediates (e.g., C19H18O3 and C19H16O3) with reduced conjugation. These structural changes are associated with decreased ROS generation and reduced antimicrobial efficacy. Proposed structures inferred from reported LC-MS analysis (Zhao et al., 2020).

Future studies should adopt more selective analytical approaches, including ESR spectroscopy and species-specific fluorescent probes (e.g., SOSG for 1O₂, DHE for ·O₂−, and HPF for ·OH), to clarify the relative contribution of each ROS type to bacterial inactivation.

Such refinement is essential to deepen the mechanistic understanding of pigment-mediated oxidative stress and to design more targeted photodynamic systems.

5. Application considerations in food systems

The successful application of natural yellow pigments as antimicrobial agents in food systems requires balancing photostability with sustained functional efficacy under real-world storage and retail conditions. In illuminated display cabinets and refrigerated logistics (typically 400–1000 lx), visible light exposure can accelerate chromophore degradation, leading to diminished ROS-mediated antibacterial activity and potential loss of microbial control. Such instability may directly impact product shelf-life and food safety, particularly in minimally processed or transparent-packaged foods where light exposure is unavoidable. Therefore, practical deployment must consider not only intrinsic photochemical behavior but also packaging architecture, product geometry, oxygen permeability, and economic feasibility. The following sections evaluate these translational constraints and discuss formulation and packaging strategies that may mitigate stability–efficacy trade-offs.

5.1. Photostability-driven limitations in packaging environments

BDMC maintains strong antibacterial activity; however, it undergoes photodegradation under visible light, exhibiting a half-life of approximately 29 h when exposed to continuous blue LED illumination (Zhao, 2020). In thin antimicrobial films or surface-applied coatings, the effective surface-area-to-volume ratio of the active layer increases relative to bulk matrices, thereby enhancing photon exposure and oxygen diffusion (Kantelberg et al., 2024). This geometric factor accelerates photochemical reactions and contributes to faster declines in ROS generation capacity, as reflected in Fig. 3. Similarly, Cur-based coatings exhibit rapid discoloration and a sharp decrease in antibacterial activity within 48 h of cold-chain lighting exposure (de Moraes Pinto et al., 2023). These findings collectively demonstrate that transparent or semi-transparent packaging is poorly suited for unstable curcuminoids, especially in short-shelf-life products such as fresh-cut vegetables, deli meats, and minimally processed fruits.

5.2. Packaging interventions: Light shielding and encapsulation

Targeted packaging modifications—such as light-shielding films (LSF) incorporating UV- and blue-absorbing polymer layers or TiO₂/SiO₂ nanocomposites—can substantially delay photodegradation of BDMC (Pal et al., 2021). For instance, LSFs with TiO₂/SiO₂ nanolayers have been shown to reduce Cur/BDMC degradation by over 60% after 48 h of exposure, preserving pigment integrity and antimicrobial function (Gennaro et al., 2025). Nanoencapsulation approaches—such as cyclodextrin inclusion complexes, liposomes/PDA–Cur nanoparticles, or multilayer nanoemulsions—effectively shield BDMC/Cur from light-induced degradation. For example, Cur nanoemulsions reduced photodegradation rate by 36–42% (Ye et al., 2024), and PDA–Cur NPs achieved a 46–50% reduction under blue/red light These findings support reported degradation rate decreases of 40–70% relative to unprotected compounds (Wang, Huang, et al., 2024). Collectively, these approaches offer complementary solutions for active packaging design, especially in systems requiring extended product display under illumination.

5.3. Process and supply-chain alignment

While effective, both LSF and NEF approaches may increase production cost or alter package permeability. For example, the incorporation of light-filtering additives or nanoencapsulation systems may require additional material inputs, specialized processing steps, or compatibility adjustments with existing film extrusion and coating technologies. These factors may influence manufacturing scalability and economic feasibility in large-scale food packaging operations. Therefore, practical implementation requires alignment with supply-chain logistics and product type. BDMC-based antimicrobial films may be better suited to food products that are distributed under vacuum, opaque secondary packaging, or frozen conditions, where light exposure is minimal or intermittent. In contrast, geniposide, with its intrinsically higher photostability, offers more consistent performance in fully illuminated displays, albeit with lower antimicrobial potency. Its application may be expanded through co-encapsulation with ROS enhancers, such as organic acids or metal ions, which could enhance antibacterial activity without compromising structural integrity. While geniposide offers superior resistance to photodegradation in transparent packaging systems, its lower intrinsic ROS-mediated antibacterial activity may restrict its effectiveness as a standalone antimicrobial agent (Li et al., 2024). Therefore, its practical use may require combination strategies or functional enhancement to compensate for this stability–efficacy imbalance.

5.4. Regulatory and sensory constraints

In addition to functional and photochemical considerations, pigment formulation must also meet regulatory requirements and consumer sensory expectations. Cur is generally recognized as safe (GRAS) in many jurisdictions and has been used as a food colorant (Zhang et al., 2026). However, at antimicrobial concentrations, its intense pigmentation and potential flavor impact may pose formulation challenges in minimally processed products (Henrique et al., 2024). To facilitate application-oriented interpretation, a benchmark comparison of representative packaging and delivery strategies under illuminated storage conditions is summarized in Table 1.

Table 1.

Benchmark comparison of representative stabilization strategies for natural yellow pigments under illuminated food storage conditions.

Pigment Delivery / Packaging strategy Light exposure scenario Photostability trend Antimicrobial outcome Application suitability Reference
BDMC Free form (LED photodynamic conditions) Visible light irradiation (430–450 nm LED) Reported photoreactivity/ROS involvement in PDT contexts Enhanced ROS generation observed during photodynamic antimicrobial tests Relevant for active photodynamic antimicrobial applications but not yet demonstrated in food packaging Amendola et al. (2025); Duterte et al. (2024)
Cur Gelatin–chitosan composite film Blue LED or visible light irradiation Improved stability compared with free Cur Log reduction of E. coli and S. aureus under photodynamic conditions Suitable for active light-responsive packaging systems Wang et al. (2022)
Cur Cyclodextrin inclusion complex (HP-γ-CD) Simulated illuminated storage Enhanced photostability relative to free form Antimicrobial performance retained under controlled light Suitable for semi-transparent or cold-chain applications Nicolaescu et al. (2025); Wang, Wei, et al. (2024)
Cur Nanoemulsion delivery system Simulated liquid food matrix (beverage/milk) Improved physicochemical and oxidative stability Moderate antimicrobial potential reported in model studies Promising for beverage or liquid food applications Dube (2025)
Cur Free coating/film without stabilization Illuminated refrigerated storage (commercial display lighting) Photodegradation under light reduces pigment integrity Antibacterial efficacy declines in illuminated storage Limited suitability for transparent/cold-chain packaging de Moraes Pinto et al. (2023)
Geniposide Free form pigment derived from Gardenia jasminoides Illuminated storage (5000–20,000 lx range) High photostability with minimal chromophore degradation Limited direct antimicrobial evidence reported High color stability but limited validated antimicrobial application Paik et al. (2001); Yang, Kong, et al. (2025)
Open in a new tab

Note: Data summarized from representative experimental studies under controlled laboratory or simulated storage conditions. Photostability trends and antimicrobial outcomes reflect qualitative interpretation of published results rather than direct cross-study quantitative comparison.

To quantitatively illustrate light-induced chromatic variation, representative time-course CIELAB parameters reported in published studies are summarized in Table 2. Under environmental or light exposure, the lightness parameter (L*) generally increases, while the yellowness coordinate (b*) markedly decreases, reflecting progressive pigment fading. These quantitative colorimetric trends further corroborate the susceptibility of curcuminoid-type yellow pigments to photodegradation in real-world storage and display conditions.

Table 2.

Representative published time-course CIELAB parameters of turmeric/curcuminoid-based yellow pigments under environmental/light exposure (summarized from published data).

Study/System Exposure condition Time L* a* b* Interpretation Reference
Turmeric oleoresin powder Environmental exposure Week 0 83.5 −3.1 59.3 Initial color parameters Kim et al. (2025)
Week 1 83.7 −3.6 47.4 Noticeable decrease in yellowness
Week 2 85.3 −3.5 32.7 Progressive fading
Week 3 85.9 −2.8 28.9 Significant loss of chroma
Week 10 87.8 −0.7 13.8 Severe discoloration
Open in a new tab

Note: Values were extracted from published experimental data and reorganized for comparative illustration. L*, a*, and b* represent CIELAB color coordinates. Increases in L* and reductions in b* indicate progressive pigment fading during exposure.

BDMC, a major component of natural curcuminoid mixtures, exhibits comparable toxicological profiles to Cur in preliminary studies (Majeed et al., 2024). Although it currently lacks explicit GRAS designation in some regions, its natural origin and promising antimicrobial potential warrant further toxicological and sensory assessments to support regulatory approval.

Geniposide is approved for use as a natural pigment or medicinal compound in several Asian countries, such as China and Japan, primarily under traditional medicine or food additive frameworks. However, it has not yet attained approval from broader regulatory agencies such as the U.S. Food and Drug Administration (FDA) or the European Food Safety Authority (EFSA), and thus remains restricted in many international markets (Szmagara, 2024). Furthermore, degradation products of curcuminoids may alter the appearance or flavor profile of foods over time, necessitating sensory evaluations during shelf-life testing to ensure consumer acceptance. However, systematic sensory studies evaluating the impact of pigment photodegradation in real food matrices remain limited, highlighting an important area for future research. While light-shielding films and nanoencapsulation approaches enhance pigment stability, their commercial implementation must consider material cost, scalability of fabrication, regulatory approval, and compatibility with existing packaging lines. These translational factors may influence large-scale adoption despite promising laboratory performance.

5.5. Summary

The optimal application of natural yellow pigments in food systems depends on coordinated strategies that address photostability, antimicrobial performance, packaging conditions, and regulatory acceptability. BDMC shows considerable promise when protected by light-shielding films or nanoencapsulation systems, which extend its functional window in illuminated settings (Hatamipour et al., 2019). Geniposide, though less potent, offers structural stability and may serve as a viable alternative in open-display formats. Ensuring compatibility between pigment chemistry, packaging architecture, and storage environment is key to achieving consistent antimicrobial efficacy without compromising product quality or consumer acceptance (Ahmed et al., 2024).

In addition to technical stability considerations, regulatory approval and sensory impact remain critical determinants of industrial translation. While Cur is GRAS in several jurisdictions, the regulatory status of BDMC and its purified forms may vary across regions, and further toxicological evaluation is warranted for concentrated antimicrobial applications (Islam et al., 2024). Moreover, comprehensive sensory assessments—including taste, color intensity, and consumer perception under real storage conditions—are still limited in the literature. These aspects represent important knowledge gaps that should be addressed in future studies to support large-scale commercialization.

A comparative overview of Cur, BDMC, and geniposide—including their structural features, photostability, and practical applications—is summarized in Supplementary Figure D, which offers a visual guide for selecting suitable pigments under various light-exposure conditions.

Visible light accelerates BDMC photodegradation, reducing ROS-mediated antibacterial activity. In transparent packaging systems, BDMC rapidly loses efficacy due to direct light exposure. In contrast, light-shielding packaging or nanoencapsulation significantly delays degradation and preserves pigment function. Geniposide, with higher intrinsic photostability, remains structurally intact under similar conditions but exhibits weaker antimicrobial activity. This schematic highlights the importance of pigment–packaging compatibility in illuminated food systems.

6. Conclusion and future perspectives

Natural yellow pigments such as BDMC, Cur, and geniposide exhibit promising antimicrobial potential through mechanisms involving ROS generation and membrane disruption (Zheng et al., 2025). However, their stability under light exposure remains a key limitation in food applications, particularly in packaging systems that allow visible light penetration. BDMC, while demonstrating strong ROS-mediated antibacterial activity, undergoes rapid degradation under illumination, leading to functional decline. In contrast, geniposide displays higher photostability but comparatively weaker antimicrobial efficacy. These findings highlight a fundamental stability–efficacy trade-off governed by molecular structure and chromophore integrity.

Future research should address several interrelated challenges to advance the practical application of these pigments in food preservation:

First, the degradation pathways of light-sensitive pigments require further clarification. Integration of advanced spectroscopic analysis, kinetic modeling, and structure–activity correlation should be used to predict pigment behavior under diverse illumination conditions, including different light spectra, packaging types, and food matrices.

Second, the development of protective delivery systems is essential. Rational formulation strategies should aim not only to shield pigments from light exposure but also to preserve controlled ROS-generating capacity. These approaches offer the potential to enhance pigment retention and performance throughout the storage period.

Third, regulatory and sensory aspects should not be overlooked. While Cur is GRAS (Sharifi-Rad et al., 2020), BDMC has not yet achieved broad regulatory approval, but its natural origin and structural similarity to Cur suggest favorable toxicological prospects. Geniposide is permitted in specific Asian countries, but its global use remains limited. Moreover, the impact of pigment concentration and degradation products on food appearance, flavor, and consumer acceptance warrants further investigation.

Finally, the design of new photosensitizers should be explored. Candidates such as glycosylated flavonoids may offer enhanced aqueous stability and moderated photo-reactivity, while conjugation-tuned carotenoid analogues or iridoid derivatives could provide improved light resistance without complete loss of functional oxidative capacity (Negi, 2025). Strategic modification of conjugation length, substitution of photo-labile β-diketone motifs, or controlled glycosylation may help balance photostability with antibacterial efficacy.

In summary, a comprehensive strategy that integrates pigment stability, antibacterial function, formulation technology, and consumer requirements is needed to realize the full potential of natural yellow pigments in food preservation. Through targeted research and application-specific optimization, these pigments can contribute to the development of safe, effective, and clean-label antimicrobial solutions for modern food systems. This review establishes a structure–function–stability framework for rational design of light-stable antimicrobial pigments in food packaging. Scalability, oxygen permeability, and cost considerations must be incorporated into future development to ensure translational feasibility.

CRediT authorship contribution statement

Lei Zhao: Writing – original draft, Conceptualization, Investigation. Ya Zhou: Investigation, Writing – review & editing. Weiguo Yue: Funding acquisition, Writing – review & editing. Chen Yuan: Writing – review & editing, Investigation. Lifang Zhang: Conceptualization, Writing – review & editing. Renyong Zhao: Conceptualization, Supervision, Writing – review & editing.

Declaration of competing interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Acknowledgements

This work was supported by the National Natural Science Foundation of China (Grant No. 32302173), the Henan Province Science and Technology Research and Development Program (Grant No. 242102310541, 242103810007), the Natural Science Foundation of Henan Province (Grant No. 252300420629), and the Fifth Batch of the National TCM Clinical Outstanding Talent Training Program (Grant No. [2022]239).

Footnotes

Appendix A

Supplementary data to this article can be found online at https://doi.org/10.1016/j.fochx.2026.103766.

Appendix A. Supplementary data

Supplementary material 1

mmc1.docx (1.3MB, docx)

Supplementary material 2

mmc2.pdf (1.4MB, pdf)

Data availability

Data will be made available on request.

References

  1. Ahmad S.M., Ibrahim F.M., Hasan A.A., Mikhlif H.M., Jwad R.S., Alhuwaymil Z.…Kommanaboyina S. Fluorescent properties of chitosan-stabilized bisdemethoxycurcumin-silver nanoparticles: Synthesis and characterization. Results in Chemistry. 2024;10 doi: 10.1016/j.rechem.2024.101719. [DOI] [Google Scholar]
  2. Ahmed R., Hira N.U.A., Wang M., Iqbal S., Yi J., Hemar Y. Genipin, a natural blue colorant precursor: Source, extraction, properties, and applications. Food Chemistry. 2024;434 doi: 10.1016/j.foodchem.2023.137498. [DOI] [PubMed] [Google Scholar]
  3. Amendola G., Di Luca M., Sgarbossa A. Natural biomolecules and light: Antimicrobial photodynamic strategies in the fight against antibiotic resistance. International Journal of Molecular Sciences. 2025;26(16) doi: 10.3390/ijms26167993. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Aminnezhad S., Maghsoudloo M., Bagheri Shahzadeh Aliakbari R. Anticancer, antimicrobial, anti-inflammatory, and neuroprotective effects of bisdemethoxycurcumin: Micro and nano facets. Micro Nano Bio Aspects. 2023;2(4):17–24. doi: 10.22034/mnba.2023.416625.1046. [DOI] [Google Scholar]
  5. Bērziņa L., Mieriņa I. Antiradical and antioxidant activity of compounds containing 1,3-dicarbonyl moiety: An overview. Molecules. 2023;28(17) doi: 10.3390/molecules28176203. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Chatterjee P., Dutta S.S., Agarwal M., Dey S., Chakraborty T. UV-A-induced photoisomerization and photodimerization of curcumin: An ion mobility mass spectrometry study. Journal of Physical Chemistry A. 2024;128(3):548–562. doi: 10.1021/acs.jpca.3c05933. [DOI] [PubMed] [Google Scholar]
  7. Chauhan K., Rao A. Clean-label alternatives for food preservation: An emerging trend. Heliyon. 2024;10(16) doi: 10.1016/j.heliyon.2024.e35815. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Chen Y., Chen M., Zhang S., Ma H., Wang J., Lu H., Wu Y. Rapid determination of geniposide in the extraction and concentration processes of Lanqin oral solution by near-infrared spectroscopy coupled with chemometric algorithms. Vibrational Spectroscopy. 2020;107 doi: 10.1016/j.vibspec.2020.103023. [DOI] [Google Scholar]
  9. Damrongrungruang T., Panutyothin N., Kongjun S., Thanabat K., Ratha J. Combined bisdemethoxycurcumin and potassium iodide-mediated antimicrobial photodynamic therapy. Heliyon. 2023;9(7) doi: 10.1016/j.heliyon.2023.e17490. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Devi L.S., Krishnan R., Begum S., Nath D., Mohanty A., Misra M., Kumar S. Curcumin as bioactive agent in active and intelligent food packaging systems: A comprehensive review. Comprehensive Reviews in Food Science and Food Safety. 2025;24(4) doi: 10.1111/1541-4337.70228. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Dube E. Nanoformulated curcumin for food preservation: A natural antimicrobial in active and smart packaging systems. Applied Biosciences. 2025;4(4) doi: 10.3390/applbiosci4040046. [DOI] [Google Scholar]
  12. Duterte M.M.D., Morales N.P., Pitiphat W., Puthongking P., Damrongrungruang T. Effects of photodynamic therapy using bisdemethoxycurcumin combined with melatonin or acetyl-melatonin on Candida albicans. Scientific Reports. 2024;14 doi: 10.1038/s41598-024-74315-6. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Gangemi C.M.A., Mirabile S., Monforte M., Barattucci A., Bonaccorsi P.M. Bioimaging and sensing properties of curcumin and derivatives. International Journal of Molecular Sciences. 2025;26(10) doi: 10.3390/ijms26104871. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Gao A., Ni Y., Chen C., Xin W., Wang Y., Zhang W. Covalent binding of geniposide metabolites to hepatic proteins: A potential mechanism for its hepatotoxicity. Chemico-Biological Interactions. 2025;408 doi: 10.1016/j.cbi.2025.111411. [DOI] [PubMed] [Google Scholar]
  15. Gennaro M., Büyüktaş D., Carullo D., Pinto A., Dallavalle S., Farris S. UV-shielding biopolymer coatings loaded with bioactive compounds for food packaging applications. Coatings. 2025;15(7):741. doi: 10.3390/coatings15070741. [DOI] [Google Scholar]
  16. Ghosh M., Sarkar N. Exploring the world of curcumin: Photophysics, photochemistry, and applications in nanoscience and biology. ChemBioChem. 2024;25(23) doi: 10.1002/cbic.202400335. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Górski M., Niedźwiadek J., Magryś A. Antibacterial activity of curcumin – A natural phenylpropanoid dimer from the rhizomes of Curcuma longa L. and its synergy with antibiotics. Annals of Agricultural and Environmental Medicine. 2022;29(3):394–400. doi: 10.26444/aaem/148393. [DOI] [Google Scholar]
  18. Guo C., Li Y., Zhang H., Zhang Q., Wu X., Wang Y., Sun F., Shi S., Xia X. A review on improving the sensitivity and color stability of naturally sourced pH-sensitive indicator films. Comprehensive Reviews in Food Science and Food Safety. 2024;23(4) doi: 10.1111/1541-4337.13390. [DOI] [PubMed] [Google Scholar]
  19. Hatamipour M., Sahebkar A., Alavizadeh S.H., Dorri M., Jaafari M.R. Novel nanomicelle formulation to enhance bioavailability and stability of curcuminoids. Iranian Journal of Basic Medical Sciences. 2019;22(3):282–289. doi: 10.22038/ijbms.2019.32873.7852. [DOI] [PMC free article] [PubMed] [Google Scholar]
  20. Henrique J.T., Biason M.V., dos Santos Mendes P., Cardoso F.A.R., Leimann F.V., Gonçalves O.H.…Droval A.A. Enhancing mortadella formulations: Exploring the impact of curcumin microcrystals, cochineal carmine, and annatto dyes on sensory preferences, stability, and antioxidant potential. Food Chemistry: X. 2024;23 doi: 10.1016/j.fochx.2024.101627. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. Islam M.R., Rauf A., Akash S., Trisha S.I., Nasim A.H., Akter M.…Thiruvengadam M. Targeted therapies of curcumin focus on its therapeutic benefits in cancers and human health: Molecular signaling pathway-based approaches and future perspectives. Biomedicine & Pharmacotherapy. 2024;170 doi: 10.1016/j.biopha.2023.116034. [DOI] [PubMed] [Google Scholar]
  22. Janga K.Y., King T., Ji N., Sarabu S., Shadambikar G., Sawant S.…Murthy S.N. Photostability issues in pharmaceutical dosage forms and photostabilization. AAPS PharmSciTech. 2018;19(1):48–59. doi: 10.1208/s12249-017-0869-z. [DOI] [PubMed] [Google Scholar]
  23. Jin C., Zongo A.W.S., Du H., Lu Y., Yu N., Nie X.…Meng X. Gardenia (Gardenia jasminoides Ellis) fruit: A critical review of its functional nutrients, processing methods, health-promoting effects, comprehensive application and future tendencies. Critical Reviews in Food Science and Nutrition. 2023;65:1–28. doi: 10.1080/10408398.2023.2270530. [DOI] [PubMed] [Google Scholar]
  24. Kah G., Chandran R., Abrahamse H. Curcumin, a natural phenol, and its therapeutic role in cancer and photodynamic therapy: A review. Pharmaceutics. 2023;15(2):639. doi: 10.3390/pharmaceutics15020639. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. Kantelberg R., Achenbach T., Kirch A., Reineke S. In-plane oxygen diffusion measurements in polymer films using time-resolved imaging of programmable luminescent tags. Scientific Reports. 2024;14:5826. doi: 10.1038/s41598-024-56237-5. [DOI] [PMC free article] [PubMed] [Google Scholar]
  26. Kim H., Oh J., Hong J. Photodegradation of turmeric oleoresin under fluorescent light and white LED: Impacts on the chemical stability, bioactivity, and photosensitizing property of curcuminoids. Molecules. 2025;30(15) doi: 10.3390/molecules30153187. [DOI] [PMC free article] [PubMed] [Google Scholar]
  27. Komonsing N., Reyer S., Khuwijitjaru P., Mahayothee B., Müller J. Drying behavior and curcuminoids changes in turmeric slices during drying under simulated solar radiation as influenced by different transparent cover materials. Foods. 2022;11:696. doi: 10.3390/foods11050696. [DOI] [PMC free article] [PubMed] [Google Scholar]
  28. Li D., Li X., Zhang X., Chen J., Wang Z., Yu Z., Wu M., Liu L. Geniposide for treating atherosclerotic cardiovascular disease: A systematic review on its biological characteristics, pharmacology, pharmacokinetics, and toxicology. Chinese Medicine. 2024;19 doi: 10.1186/s13020-024-00981-3. [DOI] [PMC free article] [PubMed] [Google Scholar]
  29. Li W., Li H., Shao Q., Liang X., Zhou Q., Tang Y. Iridoid glycosides from the flowers of Gardenia jasminoides: Isolation, characterization, and antioxidant potential. Fitoterapia. 2025;180 doi: 10.1016/j.fitote.2024.106316. [DOI] [PubMed] [Google Scholar]
  30. Majeed M., Sarang B., Anjali P., Muhamad I.A., Thazhathidath S. Subjective biosafety assessment of bisdemethoxycurcumin from the rhizomes of Curcuma longa. Toxicology Mechanisms and Methods. 2024;34(6):676–693. doi: 10.1080/15376516.2024.2326000. [DOI] [PubMed] [Google Scholar]
  31. Melo N.J., Soares J.M., Dovigo L.N., Carmona-Vargas C., Aguiar A.S.N., dos Passos A.C.…Inada N. Photodynamic action of synthetic curcuminoids against Staphylococcus aureus: Experimental and computational evaluation. Chemistry. 2024;6(4):581–600. doi: 10.3390/chemistry6040037. [DOI] [Google Scholar]
  32. de Moraes Pinto L.A., Frizzo A., Benito C.E., da Silva Júnior R.C., Alvares L.K., Pinto A.N.…Fernandes J.I.M. Effect of an antimicrobial photoinactivation approach based on a blend of curcumin and Origanum essential oils on the quality attributes of chilled chicken breast. LWT. 2023;176 doi: 10.1016/j.lwt.2023.114484. [DOI] [Google Scholar]
  33. Muchtaromah B., Safitri E.S., Fitriasari P.D., Istiwandhani J. Antibacterial activities of Curcuma mangga Val. Extract in some solvents against Staphylococcus aureus and Escherichia coli. AIP Conference Proceedings. 2020;2231 doi: 10.1063/5.0002490. [DOI] [Google Scholar]
  34. Negi A. Natural dyes and pigments: Sustainable applications and future scope. Sustainable Chemistry. 2025;6 doi: 10.3390/suschem6030023. [DOI] [Google Scholar]
  35. Nicolaescu O.E., Ionescu C., Samide A., Tigae C., Spînu C.I., Oprea B. Advancements in cyclodextrin complexes with bioactive secondary metabolites and their pharmaceutical applications. Pharmaceutics. 2025;17(4) doi: 10.3390/pharmaceutics17040506. [DOI] [PMC free article] [PubMed] [Google Scholar]
  36. Paik Y., Lee C., Cho M., Hahn T. Physical stability of the blue pigments formed from geniposide of gardenia fruits: Effects of pH, temperature, and light. Journal of Agricultural and Food Chemistry. 2001;49(1):430–432. doi: 10.1021/jf000978f. [DOI] [PubMed] [Google Scholar]
  37. Pal K., Sarkar P., Anis A., Wiszumirska K., Jarzębski M. Polysaccharide-based nanocomposites for food packaging applications. Materials. 2021;14(19) doi: 10.3390/ma14195549. [DOI] [PMC free article] [PubMed] [Google Scholar]
  38. Pramana A., Firmanda A., Arnata I.W., Sartika D., Sari E.O. Reduction of biofilm and pathogenic microorganisms using curcumin-mediated photodynamic inactivation to prolong food shelf-life. International Journal of Food Microbiology. 2024;425 doi: 10.1016/j.ijfoodmicro.2024.110866. [DOI] [PubMed] [Google Scholar]
  39. Roney M., Huq A.K.M.M., Rullah K., Zamri N.B., Mohd Aluwi M.F.F. Curcumin, a bioactive compound of turmeric (Curcuma longa) and its derivatives as α-amylase and α-glucosidase inhibitors. Cell Biochemistry and Biophysics. 2025;83(1):53–71. doi: 10.1007/s12013-024-01477-5. [DOI] [PubMed] [Google Scholar]
  40. Seidi Damyeh M., Mereddy R., Netzel M.E., Sultanbawa Y. An insight into curcumin-based photosensitization as a promising and green food preservation technology. Comprehensive Reviews in Food Science and Food Safety. 2020;19(4):1727–1759. doi: 10.1111/1541-4337.12583. [DOI] [PubMed] [Google Scholar]
  41. Sharifi-Rad J., Rayess Y.E., Rizk A.A., Sadaka C., Zgheib R., Zam W.…Martins N. Turmeric and its major compound curcumin on health: Bioactive effects and safety profiles for food, pharmaceutical, biotechnological and medicinal applications. Frontiers in Pharmacology. 2020;11 doi: 10.3389/fphar.2020.01021. [DOI] [PMC free article] [PubMed] [Google Scholar]
  42. Shi F., Pan H., Li Y., Huang L., Wu Q., Lu Y. A sensitive LC–MS/MS method for simultaneous quantification of geniposide and its active metabolite genipin in rat plasma and its application to a pharmacokinetic study. Biomedical Chromatography. 2018;32(3) doi: 10.1002/bmc.4126. [DOI] [PubMed] [Google Scholar]
  43. Singh S.K., Mazumder S., Vincy A., Hiremath N., Kumar R., Banerjee I., Vankayala R. Review of photoresponsive plasmonic nanoparticles that produce reactive chemical species for photodynamic therapy of cancer and bacterial infections. ACS Applied Nano Materials. 2023;6(3):1508–1521. doi: 10.1021/acsanm.2c04551. [DOI] [Google Scholar]
  44. Sobolewska D., Galanty A., Grabowska K., Makowska-Wąs J., Podolak I., Wróbel-Biedrawa D. Genipin—Simple but significant bioactive iridoid for therapeutical application and beyond: A review. Life. 2025;15(2) doi: 10.3390/life15020159. [DOI] [PMC free article] [PubMed] [Google Scholar]
  45. Su R., Yan H., Li P., Zhang B., Zhang Y., Su W. Photo-enhanced antibacterial activity of polydopamine–curcumin nanocomposites with excellent photodynamic and photothermal abilities. Photodiagnosis and Photodynamic Therapy. 2021;35 doi: 10.1016/j.pdpdt.2021.102417. [DOI] [PubMed] [Google Scholar]
  46. Szmagara A. Blue in food and beverages—A review of socio-cultural, economic, and environmental implications. Sustainability. 2024;16(18):8142. doi: 10.3390/su16188142. [DOI] [Google Scholar]
  47. Tahay P., Parsa Z., Zamani P., Safari N. A structural and optical study of curcumin and curcumin analogs. Journal of the Iranian Chemical Society. 2022;19(7):3177–3188. doi: 10.1007/s13738-022-02522-x. [DOI] [Google Scholar]
  48. Wang D., Wei B., Zhang Y., Xie T., Yu J., Xue Y., Kong B., Xue C., Tang Q. Multifunctional curcumin/γ-cyclodextrin/sodium chloride complex: A strategy for salt reduction, flavor enhancement, and antimicrobial activity in low-sodium foods. LWT. 2024;213 doi: 10.1016/j.lwt.2024.117085. [DOI] [Google Scholar]
  49. Wang F., Wang R., Pan Y., Du M., Zhao Y., Liu H. Gelatin/chitosan films incorporated with curcumin based on photodynamic inactivation technology for antibacterial food packaging. Polymers. 2022;14(8) doi: 10.3390/polym14081600. [DOI] [PMC free article] [PubMed] [Google Scholar]
  50. Wang X., Huang J., Lu Z., Zheng X., Zhang Q., Liu N. Polydopamine nanoparticles for red-light enhanced antibacterial and antioxidant activities of curcumin. RSC Advances. 2024;14(13):8913–8924. doi: 10.1039/D4RA01246A. [DOI] [Google Scholar]
  51. Wang X., Wang L., Fekrazad R., Zhang L., Jiang X., He G., Wen X. Polyphenolic natural products as photosensitizers for antimicrobial photodynamic therapy: Recent advances and future prospects. Frontiers in Immunology. 2023;14 doi: 10.3389/fimmu.2023.1275859. [DOI] [PMC free article] [PubMed] [Google Scholar]
  52. Wijesekara T., Xu B. A critical review on the stability of natural food pigments and stabilization techniques. Food Research International. 2024;179 doi: 10.1016/j.foodres.2024.114011. [DOI] [PubMed] [Google Scholar]
  53. Wolnicka-Glubisz A., Wisniewska-Becker A. Dual action of curcumin as an anti- and pro-oxidant from a biophysical perspective. Antioxidants. 2023;12(9) doi: 10.3390/antiox12091725. [DOI] [PMC free article] [PubMed] [Google Scholar]
  54. Xu X.-X., Li X.-J., Peng K.-W., Dong L., Xu S.-B., Dong J.-W. Microbial transformation of geniposide in Gardeniae Fructus during fermentation with aspergillus niger DQWM-G11. Natural Product Research. 2024:1–7. doi: 10.1080/14786419.2024.2412843. [DOI] [PubMed] [Google Scholar]
  55. Yang Q., Cai Y., Wang Z., Guo S., Qiu S., Zhang A. From traditional medicinal use to functional food: The pharmacological activity, hepatotoxicity mechanism and detoxification strategies of Gardenia fructus. Journal of Functional Foods. 2025;135 doi: 10.1016/j.jff.2025.107093. [DOI] [Google Scholar]
  56. Yang S., Kong Y., Yang B., Dong C. Research progress on structural modification and biological activities of geniposide and its derivatives. ChemistrySelect. 2025;10(3) doi: 10.1002/slct.202404339. [DOI] [Google Scholar]
  57. Ye Q., Kwon S., Gu Z., Selomulya C. Stable nanoemulsions for poorly soluble curcumin: From production to digestion response in vitro. Journal of Molecular Liquids. 2024;394 doi: 10.1016/j.molliq.2023.123720. [DOI] [Google Scholar]
  58. Yenigun S., Yunus B., Yasar I., Lutfi B., Ibrahim D., Ozen T. Comprehensive evaluation of Ixoroside: An iridoid glycoside from Nepeta aristata and N. baytopii, assessing antioxidant, antimicrobial, enzyme inhibitory, DNA protective properties, with computational and pharmacokinetic analyses. Journal of Biologically Active Products from Nature. 2024;14(3):286–315. doi: 10.1080/22311866.2024.2358785. [DOI] [Google Scholar]
  59. Yuan Y., Liu Q., Huang Y., Qi M., Yan H., Li W., Zhuang H. Antibacterial efficacy and mechanisms of curcumin-based photodynamic treatment against Staphylococcus aureus and its application in juices. Molecules. 2022;27(20) doi: 10.3390/molecules27207136. [DOI] [PMC free article] [PubMed] [Google Scholar]
  60. Zhang G., Zhao J.-J., Yu S., Wei S., Zheng H., Matafonova G., Zhang S. Structural insights into diketone-mediated high-rate photobleaching of dyeing wastewater. Separation and Purification Technology. 2023;322 doi: 10.1016/j.seppur.2023.124363. [DOI] [Google Scholar]
  61. Zhang H. University of British Columbia; 2022. Identification of curcuminoids in nutraceuticals and assessment of stability and bioactivity following pulsed light treatment.https://open.library.ubc.ca/collections/24/items/1.0422415 [Google Scholar]
  62. Zhang J., Su P., Chen H., Qiao M., Yang B., Zhao X. Impact of reactive oxygen species on cell activity and structural integrity of gram-positive and gram-negative bacteria in electrochemical disinfection system. Chemical Engineering Journal. 2023;451 doi: 10.1016/j.cej.2022.138879. [DOI] [Google Scholar]
  63. Zhang P., Li M., Li X., Lu X., Wang W., Sun J., Ma Q., Zhu Y. Curcumin-mediated photodynamic inactivation for smart food preservation: Antimicrobial mechanisms, nano-enabling strategies, and application challenges. Trends in Food Science & Technology. 2026;168 doi: 10.1016/j.tifs.2025.105512. [DOI] [Google Scholar]
  64. Zhang X., Zhao Y., Yan W., Wang P., Li J., Lu Y. Light stability and mechanism of monascus pigment under different lights. LWT. 2024;191 doi: 10.1016/j.lwt.2023.115666. [DOI] [Google Scholar]
  65. Zhao L. Shenyang Agricultural University; 2020. Formation conditions, structural composition, and pigment properties of fresh-cut yam yellow pigment (doctoral dissertation)https://link.cnki.net/doi/10.27327/d.cnki.gshnu.2020.000046 [Google Scholar]
  66. Zhao L., Wang D., Ma Y., Zhang Y., Zhao X. Yellow pigment formation, pigment composition, and quality of fresh-cut yam (Dioscorea opposita) slices. RSC Advances. 2020;10(2):1104–1113. doi: 10.1039/C9RA07641G. [DOI] [PMC free article] [PubMed] [Google Scholar]
  67. Zhao L., Zhou Y., Yue W., Duan D., Liu R., Yang L., Zhang L., Bian H. Photodynamic inactivation using natural pigments: Dual-ROS mechanisms, delivery strategies, and applications in food preservation. LWT. 2025;235 doi: 10.1016/j.lwt.2025.118617. [DOI] [Google Scholar]
  68. Zheng M., Wu X., Xu Y., Ma S., Shen J., Li T.…He D. Curcumin reverses high-level tigecycline resistance mediated by different mechanisms in gram-negative bacteria. Phytomedicine. 2025;136 doi: 10.1016/j.phymed.2024.156319. [DOI] [PubMed] [Google Scholar]

Further reading

  1. Divya, Joshi S., Appukuttan J., Chandrapala J., Majzoobi M. Impact of conventional and advanced techniques on stability of natural food colourants. Foods. 2025;14 doi: 10.3390/foods14183187. [DOI] [PMC free article] [PubMed] [Google Scholar]

Associated Data

This section collects any data citations, data availability statements, or supplementary materials included in this article.

Supplementary Materials

Supplementary material 1

mmc1.docx (1.3MB, docx)

Supplementary material 2

mmc2.pdf (1.4MB, pdf)

Data Availability Statement

Data will be made available on request.

Articles from Food Chemistry: X are provided here courtesy of Elsevier

RESOURCES