Behaviors of useful bacterial communities associated with the cultivation of Aurantiochytrium sp. strain L3W using fermented wastes at different pH values

Abstract

Aurantiochytrium sp. strain L3W is a halophilic and heterotrophic microorganism that produces polyunsaturated fatty acids. Fermented foods may contain lactic acid bacteria with potential probiotic effects. Here, we investigated whether a biomass mixture containing both polyunsaturated fatty acids and lactic acid bacteria can be produced as a functional eco-feed for poultry by culturing Aurantiochytrium sp. strain L3W using unsterile fermented food wastes, specifically Hiroshimana old pickles and rice vinegar production residue, at pH 4 and 7. The biomass mixture produced at both pH values contained polyunsaturated fatty acids. At pH 4, the dominant bacteria were lactic acid bacteria, such as Lactobacillus sakei and Lactobacillus coryniformis, for which probiotic effects have been reported, whereas at pH 7, lactic acid bacteria comprised a minor component of the biomass. The isolated lactic acid bacteria tolerated acidic conditions (~ pH 4). Prevalent pathogenic bacteria Salmonella, Vibrio, and Campylobacter were not detected in the food wastes. The results confirmed the feasibility of producing a functional feed additive for poultry not only to enrich polyunsaturated fatty acids in eggs but also to create a healthy intestinal environment by culturing Aurantiochytrium sp. strain L3W at pH 4 using fermented food waste in the absence of pathogens.