Table 3.
Bioactivities of almond and its by-products and their mechanisms of action.
| Mechanisms of Action | References |
|---|---|
| Antioxidant activity | |
| Free-radical scavenging activity: DPPH, ORAC, ABTS | [37,38] |
| Reducing power: FRAP | [37,39] |
| Antioxidant enzymes induction: SOD, CAT, GPx, APX | [40,41,42] |
| Cell antioxidant response modulation: Nrf2, ARE expression | [40] |
| Inhibition of lipid oxidation TBARS | [3] |
| Depletion of oxidative stress markers: ROS, GSH, DNA, and protein degradation | [42,43] |
| Anticancer activity | |
| Effectiveness against MCF-7, MDA-MB-468, HepG2, HCT-116, Saos-2, Colo-320, Colo-741, Caco-2, and B-16 cancer cell lines | [44,45,46,47,48] |
| Oxidative stress alleviation | [49] |
| Cell cycle arrest | [50] |
| Impairment of mitochondrial function and induction of caspase-mediated apoptosis | [46] |
| Inhibition of tumor migration, metastasis, and cell malignancy | [47] |
| Anti-inflammatory activity | |
| Inhibition of immune cell infiltration | [51] |
| Reduction of pro-inflammatory CKs: IL-1β, IL-6, TNF-α, CINC-1, MCP-1 | [51,52] |
| Depletion of inflammatory mediators: PGE2, NFκB, NO, ICAM-1, selectins | [53,54,55] |
| Inhibition of pro-inflammatory enzyme activity: iNOS, COX-2, MPO, PARP | [51,52] |
| Antimicrobial activity | |
| Bacteriostatic effect against both pathogenic Gram-positive and Gram-negative bacteria | [39] |
| Antifungal activity against C. albicans | [39] |
| Antiviral activity HSV-1 and HSV-2: inhibition of viral penetration, suppression of early viral proteins and viral DNA accumulation, enhancement of antiviral immune cell response | [39] |
| Prebiotic activity | |
| Enhancement of bifidobacterial and lactobacilli populations via butyrate production | [56,57] |
| Promotion of β-galactosidase activity and inhibition of β-glucuronidase and azoreductase activities | [9] |
| Suppression of pathogenic bacteria growth | [58] |
ABTS: 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid); APX: ascorbate peroxidase; ARE: antioxidant response element; CAT: catalase; CINC-1: cytokine-induced neutrophil chemoattractant 1; CKs: cytokins; COX-2: cyclooxygenase 2; DPPH: 2,2-diphenyl 1-picrylhydrazyl; FRAP: ferric reducing antioxidant power; GPx: glutathione peroxidase; GSH: reduced glutathione; HSV: herpes simplex virus; ICAM-1: intercellular adhesion molecule; IL: interleukin; MCP-1: cytokine-induced neutrophil chemoattractant 1 monocyte chemoattractant protein-1; MPO: myeloperoxidase; NFκB: nuclear factor kappa B; NO: nitric oxide; Nrf2: nuclear factor-E2-related factor 2; ORAC: oxygen radical absorbance capacity; PARP: poly(ADP-ribose) polymerase; PGE2: prostaglandin E2; ROS: reactive oxygen species; SOD: superoxide dismutase; TBARS: thiobarbituric acid reactive substances; TNF-α: tumor necrosis factor alpha.