Bioconversion of agricultural solid waste (banana tree stem) by mixed culture for use as carbon source for fermentation medium

Lignocellulosic waste can be useful if the cellulose can be freed from the lignin so that the cellulose can be converted into sugar and be used as the carbon source for fermentation medium. The glucose can be produced by anaerobic digestion which involve the process of breaking up the lignin components or delignification and later on followed by cellulose degradation. This thesis reports on the research in the delignification of lignocellulose in banana stem waste and the degradation of the cellulose into glucose. The mixed culture was collected from a banana plantation field. The process is carried out at ambient temperature in two anaerobic digesters with different organic loading rates and also with and without acclimatization respectively. From the result, it is found that glucose is recovered at the end of the digestion process but having different conversion with the anaerobic digester having the higher loading rates and acclimatized culture giving higher conversion. The percentage of lignin loss due to the delignification that occurred is determined by analyzing the sample using Klason (72% sulphuric acid) Method. The recovered glucose from the anaerobic digestion is tested as fermentation medium for Saccharomyces cerevisiae (yeast) and the results had shown that the yeast is capable of utilizing the glucose as carbon source. Hence, it can be concluded that the banana stem waste can be bioconverted into carbon source for fermentation medium