Probiotic Fermentation of Kelp Enzymatic Hydrolysate Promoted its Anti‐Aging Activity in D‐Galactose‐Induced Aging Mice by Modulating Gut Microbiota

Scope To investigate anti‐aging effects of probiotic‐fermented kelp enzymatic hydrolysate culture (KMF), probiotic‐fermented kelp enzymatic hydrolysate supernatant (KMFS), and probiotic‐fermented kelp enzymatic hydrolysate bacteria suspension (KMFP) in D‐galactose‐induced aging mice. Methods and results The study uses a probiotic‐mixture of Lactobacillus reuteri, Pediococcus pentosaceus, and Lactobacillus acidophilus strains for kelp fermentation. KMF, KMFS, and KMFP prevent D‐galactose‐induced elevation of malondialdehyde levels in serum and brain tissue of aging mice, and they increase superoxide dismutase and catalase levels and total antioxidant capacity. Furthermore, they improve the cell structure of mouse brain, liver, and intestinal tissue. Compared with the model control group, the KMF, KMFS, and KMFP treatments regulate mRNA and protein levels of genes associated with aging, the concentrations of acetic acid, propionic acid, and butyric acid in the three treatment groups are more than 1.4‐, 1.3‐, and 1.2‐fold increased, respectively. Furthermore, the treatments affect the gut microbiota community structures. Conclusions These results suggest that KMF, KMFS, and KMFP can modulate gut microbiota imbalances and positively affect aging‐related genes to achieve anti‐aging effects. Aging is a complex physiological process with adverse states. The fermentation of marine algae by probiotics is a research hotspot in the field of anti‐aging. The effects of kelp enzymatic hydrolysate fermented by probiotics on D‐galactose‐induced aging mice, and possible anti‐aging mechanisms are examined. The results showed that the probiotic fermented kelp would be a potential anti‐aging functional nutritional food.