Production of reducing sugar from food waste using hydrolytic microorganisms

Abstract

Rapid global economy and population increase play a significant role in food waste (FW) production. Improper food waste management is a considerable challenge for the entire world since FW pollutes the environment and risks human and animal health. However, transforming food waste into value-added chemicals is an area of intensive research since they contain organic compounds. To this effect, we investigate the possibility of enhancing the food waste hydrolysis using microorganisms. In this research, FW was first blended and diluted at different concentration ratios (Fw: water) of 2:1,1:1,1:2 and 1:3. After a simple solid-liquid separation, the liquid was hydrolysed by fungi rich in hydrolytic enzymes at their log phases. The moisture content of FW was 15.68 %. This study aims to produce glucose from food waste using the three types of hydrolytic microorganisms: Aspergillus oryzae, aspergillus aculeatus and Candida rugosa. Moreover, we discussed the best ratio variation of microbes towards food waste hydrolysis. This study analysed glucose levels using the DNS method by measuring the absorbance through a spectrophotometer at 540 nm. The results showed that the highest glucose concentration of 16.5 g/l was obtained after 48 hours by mixing all microorganisms using a ratio of 2:1 (FW 2:1 M). The highest glucose (g/l) concentration from a ratio of 2:1 obtained from FW hydrolysis by Candida rugosa, Aspergillus oryzae and Aspergillus aculeatus after 48 hours were 13.05,14.31,15.9, respectively. Therefore, the current finding indicates that hydrolytic microorganisms could save the pretreatment cost of food waste and greatly enhance food waste degradation.