Utilization Agricultural By-Product as Inducers and Carbon Sources for Hemicellulolytic Enzyme Cocktails Production

Abstract

The main components of 90 % total dry weight of lignocellulosic agricultural by-product are lignin, cellulose, hemicellulose and pectin. Lignocellulosic biomass can be utilized optimally after bioconversion into its constituent components to achieve the zero waste by-product. This research, hemicellulose extracted from water hyacinth and corn cobs were used as inducers and nutrients mixed with glucose. Those mixed medium was used to grow the recombinant Escherichia coli BL21 and produce enzyme cocktails of β-D-xylosidase and α-L-arabinofuranosidase. The growth curve profile was measured by OD6 0 0 density and enzyme cocktails activity was measured by DNS method. The best growth curve profile on modified chemically defined medium with the ratio of water hyacinth xylan as carbon source (mCDM-WX) and glucose was 1:3, while the ratio of corn cobs xylan (mCDM - CX) and gluciose was 1:1. The growth phase showed the exponential phase of mCDM-WX with glucose (1:3) and mCDM-CX with glucose (1:1) started from 0 to 8 hours, while the stationary phase started from 10 to 12 (mCDM-WX) and 8 to 16 hours (mCDM-CX), respectively. Ratio of mCDM-CX mixed with glucose (1:1) indicated the highest media alternative for growing recombinant E. coli BL21 and producing β-xylosidase and α-L-arabinofuranosidase.