Delignification of Sugarcane Straw (Saccharum officinarum L.) Using Pleurotus ostreatus and Laccase Crude Extract

• Main Author: Ramadianti Shafitri, Tri
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/42751
• Institution: Institut Teknologi Bandung

Sugarcane straw is potential agroindustrial waste for production fermentable sugar products, such as xylitol, bioethanol, biogas, and chemicals, due to its abundance and carbohydrate content. However, the carbohydrates are hardly accessible for fermentation process because lignin content in this lignocellulotic material is difficult to hydrolise. Pretreatment can help to overcome this limitation. The present study investigates lignin degradation and carbohydrates content from sugarcane straw pretreated with Pleurotus ostreatus through Solid-state fermentation (SSF) and enzymatic delignification using crude laccase. The effect of fermentation time and temperature enzymatic delignification were also investigated. Mineral salts, 150 ?M CuSO4, and 7 g/L yeast extract were used as nutrient addition to perform SSF. Enzymatic delignification was performed at 30, 40, and 50?, 150 rpm, for 24 hours. During 25 days fermentation, lignin content decreased, cellulose and hemicellulose increased, although some carbohydrates is consumed by fungi. The best result was observed in solid-state fungal pretreatment at 20 days fermentation, with cellulose 38.09%, hemicellulose 35.82%, and delignification 26.44%. However, maximum delignification obtained was 33.37% in enzymatic delignification with 15.07 U/(mg protein) laccase at 30?, the cellulose content is 29.14% and hemicellulose 29.62%. Thorough study of the carbohydrate content was carried out by sugar free analysis. Further analysis of the hydrolysate enzymatic delignification was carried out by Gas Chromatography-Mass Spectrometry (GC-MS).