Facile bioconversion of vegetable food waste into valuable organic acids and green fuels using synthetic microbial consortium

The production of various organic acids from vegetable waste via a facile and cost-effective method utilizing characterized synthetic microbial consortia is described in this study. Five bacterial species with the ability to produce organic acids from vegetable waste biomass were isolated and identified as Lactobacillus casei, Lactobacillus acidophilus, Bacillus megaterium, Pseudomonas florescence and Escherichia coli. Using these cultures, mixed acid fermentation was developed and was efficient in producing various organic acids. The total organic acids accumulated using optimized fermentation conditions was found to be 72.44±3.43 g L−1. The acetic acid was produced as major acid accumulated up to 25.27±1.26g L−1, followed by lactic acid 19.11±1.73 g L−1. Efforts were also put forth to check the ability to produce methane by the anaerobic digestion process. Up to 14.97 mL g−1 biomass methane was produced during the anaerobic digestion process. The technology developed in this study is a carbon-neutral process for managing vegetable food waste with economic benefit. The developed technology will have great economic potential and add value to vegetable food waste management.