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Access Type
Campus Access
Document Type
thesis
Degree Program
Food Science
Degree Type
Master of Science (M.S.)
Year Degree Awarded
2012
Month Degree Awarded
May
Keywords
Type 2 diabetes, phenolic bioactives, apple, blueberry, lactic acid bacteria, probiotics
Abstract
Type 2 diabetes is a worldwide and costly disease that requires complex cellular metabolic breakdown for its development. The onset of this disease is indicated by an abnormal elevated blood glucose level (hyperglycemia) and coexistence with hypertension. Apple and blueberry are the two popular fruits in the U.S. that are high in bioactive phenolic compounds. The objectives of this thesis were to investigate the synergistic health benefits of apple cider and blueberry juice for potential management of early stages of type 2 diabetes using in vitro enzyme assay models and enhance their synergistic effects through fermentation using probiotic strains of lactic acid bacteria. Apple cider and whole blueberry juice were combined at 5 different ratios. Synergistic interaction of the phenolic bioactives between the two juice sources was observed in all assays. For maintenance of high α-glucosidase, α-amylase and ACE inhibition activities, a proportion of 80% apple cider and 20% whole blueberry juice was selected as the optimum combination reflecting maximum health benefits to potentially manage hyperglycemia and hypertension associated with type 2 diabetes. The 80/20 apple cider and blueberry juice combination was fermented at 24 and 48 h using Lactobacillus helveticus R0052 and Bifidobacterium longum isolate. High inhibition of α-glucosidase, α-amylase and ACE enzymes was observed in apple cider/blueberry juice combination. Strong antimicrobial activity against H. pylori was exerted by L. helveticus- and B. longum-fermented sample at 48 h. A possible mode of action through the synergy between lactic acid and proline oxidation pathway was suggested.
DOI
https://doi.org/10.7275/2752896
First Advisor
Kalidas Shetty