Analysis of Microbial Populations and Metabolism of Anthocyanins by Mice Gut Microflora Fed with Blackberry Powder

Abstract

Blackberries contain non-nutritive phytochemicals which are abundant in berry fruits. Among these chemicals, anthocyanins are responsible for the bright colors seen in many fruits and plant as well as have potential health properties against chronic diseases like cancer, cardiovascular disease, diabetes, and obesity. Therefore, two anthocyanins, cyanidin-3-glucoside and cyanidin-3-rutinoside were adopted to evaluate metabolism rate by cecal microflora which were acquired from four treatments 1) lean control (L-CTL), 2) obese control (O-CTL), 3) aged blackberries supplemented at 10% (w/w) (O-AB10), and 4) fresh blackberries supplemented at 10% (w/w) (OFB10). Furthermore, a non-culture based technique; polymerase chain reaction-based denaturing gradient gel electrophoresis (PCR-based DGGE) and further sequencing were performed to identify microbial populations. There were differences in the metabolism rates of two anthocyanins (cyanidin-3-glucoside and cyanidin-3-rutinoside) between two control groups and two treatment groups while no differences were shown within two control groups. The sequencing results based on DGGE represented that Lachnospiraceae bacteria found predominantly in blackberry treatment mice, Lactobacillus johnsonii was dominant species in both control and treatment groups. Bifodobacterium pseudolongum was identified in only obese control samples. In conclusion, differences in diets and body phenotype can have an effect on gut microflora and subsequently affect the metabolism rate of anthocyanins. Also, blackberry treatment groups demonstrated a more rapid anthocyanin degradation rate than the un-adapted control groups.