FERMENTATION OF WHOLE APPLE JUICE USINGLACTOBACILLUS ACIDOPHILUSFOR POTENTIAL DIETARY MANAGEMENT OF HYPERGLYCEMIA, HYPERTENSION, AND MODULATION OF BENEFICIAL BACTERIAL RESPONSES

Apple juice from four cultivars were fermented for 0, 24, 48 and 72 h using Lactobacillus acidophilus and their effects related to management of hyperglycemia, hypertension, inhibition of Helicobacter pylori and proliferation of probiotic Bifidobacterium longum were evaluated using in vitro models. All the assays were carried out at fermented acidic pH and by adjusting the pH to 6.0–7.0. Total soluble phenolics, 2,2-diphenyl-1-picrylhydrazyl-linked free radical-scavenging activity and α-amylase inhibition decreased over 72 h. Overall, α-glucosidase inhibition and hypertension-relevant angiotensin-converting enzyme inhibition decreased after 72 h for pH-adjusted samples, whereas contrasting results were obtained for fermented acidic pH samples. Only at 48- and 72-h fermented acidic pH samples had H. pylori inhibitory activity. Further investigations into mechanisms using proline revealed that H. pylori inhibition was not through inhibition of proline oxidation via proline dehydrogenase. No inhibition was observed when samples that had H. pylori inhibition were further tested for their effect on probiotic Bifidobacterium longum growth. PRATICAL APPLICATIONS In this study, for the first time, fermentation of apple juice using lactic acid bacteria was shown to have relevance in managing hyperglycemia and hypertension using in vitro models. This approach was also shown to have potential to inhibit stomach ulcer relevant bacterium Helicobacter pylori. Further, we also established that fermented extracts will not inhibit the beneficial intestinal lactic acid bacteria. This research provides biochemical rationale for further in vivo studies based on the in vitro enzyme assay models used in this study. Further, this study can provide biochemical rationale for the development of fermented food design strategies that can have potential to reduce hyperglycemia linked to type 2 diabetes and related chronic diseases. This research also provides new approaches to develop low-cost, natural antimicrobials with no side effects, which can be used as whole food dietary bioactive to manage and/or prevent infectious and diet-linked chronic diseases.