Delignification and determination of sugar concentration in fertilizer as the preliminary process of bioethanol production by Aspergillus fumigatus

Water hyacinth is an aquatic weed that causes an imbalance of the ecosystem hence, it needs to be processed into useful products. This research conducted the degradation of lignocellulose-containing biomass, utilizing Aspergillus fumigatus fungi to form bioethanol. This study was initiated with the cultivation of A.fumigatus in Potato Dextrose Broth media and the preparation of water hyacinth as a substrate up to 25 mesh in size. Pretreatment was carried out using varying ratios of fungi to substrate of 1: 1, 1: 5, and 1:10 and contact time is 24, 72, and 120 hours. Furthermore, the lignin level was determined using the gravimetric method and hydrolysis was carried out afterwards in order to prepare the sugar for the fermentation procedure. The sugar content produced was analyzed using the DNS method. In this study, the highest allowance for lignin at the pretreatment stage was 25.9%, this produced the highest sugar at the hydrolysis stage (0.5 g/L). Fungi A. fumigatus functions as a biocatalyst which is suitable in the delignification process as a pretreatment and hydrolysis. A fermentation procedure and further research is needed to determine the potential of water hyacinth as a raw material in the production of bioethanol.