Table of Contents
Biotechnology Research International
Volume 2011, Article ID 574983, 7 pages
Research Article

A Statistical Approach for Optimization of Simultaneous Production of β-Glucosidase and Endoglucanase by Rhizopus oryzae from Solid-State Fermentation of Water Hyacinth Using Central Composite Design

Microbiology Laboratory, Department of Zoology, Molecular Biology & Genetics, Presidency University, 86/1, College Street, Kolkata, 700 073, India

Received 8 March 2011; Revised 6 April 2011; Accepted 7 April 2011

Academic Editor: Triantafyllos Roukas

Copyright © 2011 Moumita Karmakar and Rina Rani Ray. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


The production cost of β-glucosidase and endoglucanase could be reduced by using water hyacinth, an aquatic weed, as the sole carbon source and using cost-efficient fermentation strategies like solid-state fermentation (SSF). In the present study, the effect of different production conditions on the yield of β-glucosidase and endoglucanase by Rhizopus oryzae MTCC 9642 from water hyacinth was investigated systematically using response surface methodology. A Central composite experimental design was applied to optimize the impact of three variables, namely, substrate concentration, pH, and temperature, on enzyme production. The optimal level of each parameter for maximum enzyme production by the fungus was determined. Highest activity of endoglucanase of 495 U/mL was achieved at a substrate concentration of 1.23%, pH 7.29, and temperature 29.93°C whereas maximum β-glucosidase activity of 137.32 U/ml was achieved at a substrate concentration of 1.25%, pH 6.66, and temperature 32.09°C. There was a direct correlation between the levels of enzymatic activities and the substrate concentration of water hyacinth as carbon source.