Feasibility study on biostimulation of electron transfer characteristics by edible herbs-extracts

As antioxidants could scavenge free radicals and active oxygen groups, their electrochemical characteristics were also closely related to electron transfer (ET) capabilities. Prior studies revealed that decolorized metabolites (DM) of textile dyes as electron shuttles (ESs) could stimulate ET capabilities of reductive decolorization and bioelectricity generation (RD&BG). Cyclic voltammetric analysis showed that several medicinal herbs owned promising redox-mediating capabilities to be antioxidants or ESs. Due to such dual characteristics, supplementation of intact tea extracts could stimulate power generation of microbial fuel cells, no matter what degree of tea fermentation was treated. With the abundance of polyphenolics, antioxidant potency of tea extracts was positively associated to redox mediating characteristics. Electron-shuttling mechanisms of compositions of tea extract (e.g., epigallocatechin gallate, gallocatechin, gallic acid) were also proposed.