Table 2. Context-stratified analytical mapping of included studies across mechanistic regimes and physicochemical constraints (n = 26)a.
| Study ID | Year | Producing organism | Strain/isolate | Assay context | Biological activity domain(s) | Primary endpoint type | Key outcome (one-line summary) | Mechanistic regime | Physicochemical constraint |
|---|---|---|---|---|---|---|---|---|---|
| Included_01_k_2005 (ref. 48) | 2005 | Zymomonas mobilis | ZM1 | Cell-based; material matrix | Anti-inflammatory | Cytokine modulation; barrier integrity | Reduced IL-1α improved barrier function | Interface-mediated system | Surface interaction/barrier formation |
| Included_02_am_2012 (ref. 49) | 2012 | Bacillus subtilis | NRC1aza | Chemical; cell-based | Antioxidant | DPPH; cell viability/apoptosis | Sulfated levan derivatives showed enhanced bioactivity | Reaction-diffusion system | Radical accessibility/charge interaction |
| Included_03_m_2013 (ref. 50) | 2013 | Bacillus licheniformis | FRI MY-55 | Microbiota/fermentation assay | Prebiotic | Bacterial growth/utilization | Low molar mass (LMW) levan promoted probiotic growth | Enzymatic accessibility system | Steric hindrance/substrate accessibility |
| Included_04_mat_2013 (ref. 51) | 2013 | Bacillus subtilis | Honey isolate | Chemical; cell-based | Antioxidant | ORAC; enzyme activity; apoptosis markers | Fraction dependent antioxidant and anti-initiation effects | Reaction-diffusion system | Diffusion + fraction solubility |
| Included_05_r_2015 (ref. 11) | 2015 | Acetobacter xylinum | NCIM 2526 | Chemical; cell-based | Antioxidant; anti-inflammatory | Radical scavenging; cytokine response | Levan showed antioxidant and anti-inflammatory activity | Multi-regime system | Mixed constraints (diffusion + interaction) |
| Included_06_a_2019 (ref. 52) | 2019 | Bacillus subtilis | DSM 347 | Microbiota/fermentation assay | Prebiotic | Growth kinetics | Levan oligosaccharides (LOS) enhanced microbial utilization | Enzymatic accessibility system | Chain length-dependent accessibility |
| Included_07_m_2019 (ref. 53) | 2019 | Bacillus subtilis natto | KB1 | Chemical; cell-based | Antioxidant | Radical scavenging; cytotoxicity | LMW levan showed cosmetic relevant antioxidant activity | Reaction-diffusion system | Diffusion/molecular mobility |
| Included_08_a_2020 (ref. 65) | 2020 | Bacillus subtilis | AF17 | Chemical | Antioxidant | Radical scavenging; reducing power | UHMW levans showed antioxidant activity high molar mass | Aggregation-mediated system | Aggregation/surface area effects |
| Included_09_f_2020 (ref. 41) | 2020 | Bacillus megaterium | PFY-147 | Chemical | Antioxidant | Multi-radical scavenging | (HMW) levan showed strong antioxidant capacity | Interface-mediated system | Morphology/interfacial exposure |
| Included_10_tim_2020 (ref. 12) | 2020 | Bacillus sp. | Honey isolate | Organism-level functional assay; microbiota/fermentation | Anti-inflammatory; prebiotic | Tissue response; growth index | Barrier mediated gastroprotection and prebiotic effects | Barrier-mediated system | Adhesion/film formation |
| Included_11_sv_2021 (ref. 55) | 2021 | Bacillus sp. | 4A | Microbiota/fermentation assay | Prebiotic | Growth/fermentation indices | Hydrolyzed levan improved probiotic growth | Enzymatic accessibility system | Depolymerization/accessibility |
| Included_12_thn_2021 (ref. 56) | 2021 | Bacillus velezensis | VTX20 | Chemical | Antioxidant | Radical scavenging | Levan rich EPS showed antioxidant activity | Reaction-diffusion system | Diffusion-controlled interaction |
| Included_13_g_2022 (ref. 57) | 2022 | Pseudomonas mandelii | NR | Material/functional system | Antioxidant (material performance) | Film radical scavenging | Levan based films exhibited antioxidant properties | Material-mediated system | Matrix structure/diffusion limitation |
| Included_14_b_2023 (ref. 58) | 2023 | Bacillus subtilis | MTCC 441 | Chemical | Antioxidant | Radical scavenging | HMW levan showed strong antioxidant activity | Aggregation-mediated system | Aggregation/functional group exposure |
| Included_15_oe_2023 (ref. 13) | 2023 | Halomonas elongata | 153B | Chemical; cell-based | Antioxidant; anti-inflammatory | Radical scavenging; protein denaturation | Multifunctional antioxidant/anti-inflammatory effects | Multi-regime system | Mixed constraints |
| Included_16_s_2023 (ref. 59) | 2023 | Bacillus sp. | EPS003 | Chemical; cell-based | Antioxidant | Radical scavenging; cytotoxicity | Antioxidant activity with low cytotoxicity | Reaction-diffusion system | Diffusion/solubility |
| Included_17_sa_2023 (ref. 60) | 2023 | Pseudomonas aeruginosa | HI1 | Chemical; cell-based; microbiota/fermentation | Antioxidant; anti-inflammatory; prebiotic | Oxidative markers; cytokines; growth indices | Multifunctional modulation of inflammation and microbiota | Multi-regime system | System-dependent constraints |
| Included_18_ym_2023 (ref. 38) | 2023 | Enterococcus faecium | MC-5 | Material/functional system | Antioxidant (material performance) | Film radical scavenging | LMW levan enhanced composite film bioactivity | Material-mediated system | Matrix dispersion/accessibility |
| Included_19_j_2024 (ref. 10) | 2024 | Bacillus subtilis | PR-C18 | Chemical; microbiota/fermentation | Antioxidant; prebiotic | Radical scavenging; growth assays | LMW levan showed dual antioxidant-prebiotic effects | Hybrid system | Diffusion + enzymatic accessibility |
| Included_20_k_2024 (ref. 61) | 2024 | Bacillus megaterium | KM3 | Chemical | Antioxidant | Radical scavenging; thermal behavior | Ordered conformation linked to antioxidant activity | Conformation-mediated system | Structural organization |
| Included_21_vs._2024 (ref. 37) | 2024 | Paenibacillus polymyxa | 88A | Chemical | Antioxidant | DPPH; ABTS scavenging | Dose dependent antioxidant activity | Reaction-diffusion system | Concentration/diffusion |
| Included_22_wa_2024 (ref. 14) | 2024 | Coculture | OP315322/OP363928 | Chemical; cell-based; microbiota/fermentation | Antioxidant; anti-inflammatory; prebiotic | Radical scavenging; gene expression; growth | Enhanced multifunctional activity in coculture system | Multi-regime system | Complex interaction environment |
| Included_23_h_2025 (ref. 42) | 2025 | Bacillus amyloliquefaciens | JM033 | Cell-based; microbiota/fermentation; organism-level functional assay | Prebiotic; immunomodulatory | Immune markers; microbiota composition | LMW levan restored immune and microbiota balance | Enzymatic + biological system | Accessibility + host interaction |
| Included_24_j_2025 (ref. 30) | 2025 | Bacillus licheniformis | SFLV-ZM107 | Microbiota/fermentation assay | Prebiotic | Growth kinetics; fermentation indices | LMW levan enhanced probiotic fermentation | Enzymatic accessibility system | Chain length/accessibility |
| Included_25_nny_2025 (ref. 9) | 2025 | Gluconobacter cerinus | UELBM11 | Chemical | Antioxidant | Radical scavenging | Levan showed hydroxyl and ABTS scavenging | Reaction-diffusion system | Radical interaction |
| Included_26_r_2025 (ref. 35) | 2025 | Bacillus siamensis | KKSB4 et al. | Chemical; microbiota/fermentation | Antioxidant; prebiotic | Radical scavenging; growth index | UHMW levans showed variable bioactivity | Aggregation + accessibility system | Aggregation vs. accessibility trade-off |
a
Biological activity domains in Table 2 are strictly categorized according to the review's predefined scope (antioxidant, anti-inflammatory, and prebiotic/microbiota-modulating effects). Molar mass (MW) terminology adheres to the structural stratification defined in the methods: levan oligosaccharides (LOS, <10 kDa), low (LMW, 10–100 kDa), high (HMW, 100–1000 kDa), and ultra-high (UHMW, >1000 kDa) molar masses. Abbreviations: ABTS, 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid); DPPH, 2,2-diphenyl-1-picrylhydrazyl; ORAC, oxygen radical absorbance capacity; IL, interleukin.