OPTIMIZATION OF INITIAL PH AND OSMOTIC PRESSURE STRESS FOR BETA GLUCAN PRODUCTION FROM SCLEROTIUM ROLFSII

• Main Author: Murtasya Sunandi, Nazwa
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/83326
• Institution: Institut Teknologi Bandung

Sclerotium rolfsii is a potential fungus for beta glucan production, which can be developed in various industries due to its superior physical properties. However, its application for large-scale industries faces challenges such as high production costs, low yields, and long production times, necessitating optimization of the production process. This study aims to increase the total beta glucan production (structural + exopolysaccharides (EPS)) from S. rolfsii in MIS medium (Cornstarch, Fish Broth, and Sucrose) using bioprocess strategies through initial pH and osmotic stress treatments. The optimization process was conducted in two stages: first, the initial pH was optimized to determine the best initial pH treatment, which was then used for osmotic stress optimization. This research uses a factorial completely randomized design consisting of initial pH treatments (3, 4, and 5), osmotic stress treatments (NaCl 0.5%, 1%, and 1.5%), and cultivation time (48, 72, 96, 120 hours) with 3 replications. The parameters observed were total beta glucan yield, dry biomass yield, and oxalic acid content. Structural beta glucan extraction was performed on the formed biomass, while EPS beta glucan extraction was performed on the cultivation medium from 48 to 120 hours. Initial pH treatment of 4 resulted in the highest average dry biomass yield and total beta glucan yield, significantly different from other initial pH treatments and the control. Further tests on the interaction between initial pH and cultivation time on total beta glucan yield showed that initial pH 4 at 96 hours (9.33 mg/ml) produced the highest total beta glucan yield, significantly different from other treatments, and was determined as the best initial pH treatment for osmotic stress optimization. Initial pH treatment reduced the oxalic acid content, a by-product of beta glucan production from S. rolfsii, with initial pH 3 showing the lowest content. Under 1% osmotic stress treatment, the highest average total beta glucan yield was obtained, significantly different from other osmotic stress treatments and the control. The average biomass yield under osmotic stress treatment did not significantly differ from the control under 1% and 0.5% treatments, while a decrease in biomass was observed under 1.5% treatment compared to the control. Further tests on the interaction between osmotic stress and cultivation time on total beta glucan yield showed that 1% osmotic stress treatment at 96 hours produced the highest total beta glucan yield (10.58 mg/ml), significantly different from other treatments. The best treatment combination of initial pH 4 with 1% osmotic stress at 96 hours of cultivation time was identified to enhance total beta glucan production from S. rolfsii in MIS medium.