Kombucha tea as an anti-hyperglycemic agent in humans with diabetes - a randomized controlled pilot investigation

Identification of Key Parameters Inducing Microbial Modulation during Backslopped Kombucha Fermentation

The aim of this study was to assess the impact of production parameters on the reproducibility of kombucha fermentation over several production cycles based on backslopping. Six conditions with varying oxygen accessibility (specific interface surface) and initial acidity (through the inoculation rate) of the cultures were carried out and compared to an original kombucha consortium and a synthetic consortium assembled from yeasts and bacteria isolated from the original culture. Output parameters monitored were microbial populations, biofilm weight, key physico-chemical parameters and metabolites. Results highlighted the existence of phases in microbial dynamics as backslopping cycles progressed. The transitions between phases occurred faster for the synthetic consortium compared to the original kombucha. This led to microbial dynamics and fermentative kinetics that were reproducible over several cycles but that could also deviate and shift abruptly to different behaviors. These changes were mainly induced by an increase in the Saccharomyces cerevisiae population, associated with an intensification of sucrose hydrolysis, sugar consumption and an increase in ethanol content, without any significant acceleration in the rate of acidification. The study suggests that the reproducibility of kombucha fermentations relies on high biodiversity to slow down the modulations of microbial dynamics induced by the sustained rhythm of backslopping cycles.

Metabolomics and in-vitro bioactivities studies of fermented Musa paradisiaca pulp: A potential alpha-amylase inhibitor

The in-vitro synthesis of bio-compounds via fermentation is a promising route for bioactive molecules intended for disease control and management. Therefore, this study evaluated the effect of fermentation on the antioxidants, antihyperglycemic and anti-inflammatory properties and the resultant chemometric phytochemical profiles of unripe plantain fruits. The results revealed that Escherichia coli and Propionibacterium spp. are suspected as the key fermenters. The E coli showed negative results to the pathogenicity test; Propionibacterium appeared to be opportunistic. A significant increase in the total polyphenols and protein and decreased flavonoids was recorded in the phytochemical profile of the methanolic extract of the fermented unripe plantain pulp; however, the ascorbic acid content was not significantly altered. The 1H NMR fingerprint showed that there is a closely related chemical shift among the shorter fermentation time (days 2-6) and the unfermented, while the more extended fermentation periods (days 7-12) with enhanced bioactivities were closely related based on the chemometrics analyses. Furthermore, the UPLC-QTOF-MS analysis annotated the presence of bioactive compounds in the day-9 fermented sample: polyhydroxy glucose conjugates (3-Methoxy-4-hydroxyphenyl 6-O-(3,4,5-trihydroxybenzoyl)-beta-D-glucopyranoside), short chain peptide (leucyl-glycyl-glycine), amino acid derivatives (4-Aminophenylalanine, and N-Acetylhistidine), linear and cyclic fatty acid derivatives (palmitoyl putrescine, ricinoleic acid, phytosphingosine, gabalid, rubrenoic acid, 2-aminocyclopentanecarboxylic and cystodienioc acid). The synergistic effect of these newly formed compounds and the increase in the phenolic content of the day-9 fermented unripe plantain may account for its more potent antioxidant, anti-inflammatory and antihyperglycemic activity. Therefore, the products obtained from the day 9 fermentation of unripe plantain pulp may serve as potential nutraceutical agents against gastro-enteric sugar digestion and absorption and sugar-induced oxidative stress, inflammation and metabolic disease.

Research Progress on the Effect and Mechanism of Tea Products with Different Fermentation Degrees in Regulating Type 2 Diabetes Mellitus

A popular non-alcoholic beverage worldwide, tea can regulate blood glucose levels, lipid levels, and blood pressure, and may even prevent type 2 diabetes mellitus (T2DM). Different tea fermentation levels impact these effects. Tea products with different fermentation degrees containing different functional ingredients can lower post-meal blood glucose levels and may prevent T2DM. There are seven critical factors that shed light on how teas with different fermentation levels affect blood glucose regulation in humans. These factors include the inhibition of digestive enzymes, enhancement of cellular glucose uptake, suppression of gluconeogenesis-related enzymes, reduction in the formation of advanced glycation end products (AGEs), inhibition of dipeptidyl peptidase-4 (DPP-4) activity, modulation of gut flora, and the alleviation of inflammation associated with oxidative stress. Fermented teas can be used to lower post-meal blood glucose levels and can help consumers make more informed tea selections.