In vitro bioassay based screening of antihyperglycemia and antihypertensive activities of Lactobacillus acidophilus fermented pear juice

Four commonly consumed cultivars of pear were homogenized to extract their juice, fermented using Lactobacillus acidophilus for 0, 24,48 and 72 h and their potential for management of hyperglycemia and hypertension were evaluated using in vitro assays. The pH of the juices was adjusted to 6.0-7.0 before fermentation and assays at each time point were carried out at fermented acidic pH and by adjusting the pH to 6.0-7.0. Overall there was a decrease in total soluble phenolics and DPPH-linked free radical scavenging activity with fermentation over a period of 72 h. alpha-Glucosidase inhibitory activity increased or remained constant for both pH adjusted and fermented acidic pH samples. Initial ACE inhibitory activity decreased for all samples with fermentation. Epicatechin and quercetin derivatives were the major phenolic compounds in the fermented samples. Industrial relevance: In this study, fermenting pear juice with lactic acid bacteria was shown to have potential for use in diet designs for managing type 2 diabetes due to the enhanced inhibitory bioactivity of the juice using relevant in vitro enzyme assay models. Our research provides innovative strategies to develop low-cost dietary support of common fruits enriched in bioactives to compliment traditional drug and nutritional therapies to potentially combat type 2 diabetes. Also from our fermentation-based strategies we can advance functional food designs using sound biochemical rationale to potentially manage early stage type 2 diabetes and its oxidative complications based on further animal and clinical studies. Our approach may be used as a novel method to deliver probiotic lactic acid bacteria in lactose intolerant people in fermented fruit-based system with multiple potential health benefits. (C) 2011 Elsevier Ltd. All rights reserved.