Optimization of saccharification potential of recombinant xylanase from Bacillus licheniformis

Irfana Iqbal,Ali R. Awan,Khalid M. Zia,Asma Zafar,Afshan Kaleem,Muhammad N. Aftab

doi:10.1080/21655979.2017.1373918

Abstract

ABSTRACTSaccharification potential of xylanase enzyme cloned from Bacillus licheniformis into E. coli BL21 (DE3) was evaluated against plant biomass for the production of bioethanol. The expression of cloned gene was studied and conditions were optimized for its large scale production. The parameters effecting enzyme production were examined in a fermenter. Recombinant xylanase has the ability to breakdown birchwood xylan to release xylose as well as the potential to treat plant biomass, such as wheat straw, rice straw, and sugarcane bagass. The saccharification ability of this enzyme was optimized by studying various parameters. The maximum saccharification percentage (84%) was achieved when 20 units of recombinant xylanase were used with 8% sugarcane bagass at 50°C and 120 rpm after 6 hours of incubation. The results indicated that the bioconversion of natural biomass by recombinant xylanase into simple sugars can be used for biofuel (bioethanol) production. This process can replace the use of fossil fuels, and the use of bioethanol can significantly reduce the emission of toxic gases. Future directions regarding pre-treatment of cellulosic and hemicellulosic biomass and other processes that can reduce the cost and enhance the yield of biofuels are briefly discussed.

Highlights

The optimization of the various parameters involved in the enhanced expression of recombinant xylanase enzyme as well as for the maximum saccharification of plant biomasses are discussed
The cell walls of plants are the chief repository of fixed carbon in the environment, and are comprised of three main polymeric components: hemicellulose, cellulose and lignins.[4]
The conversion of xylan into valuable products represents a significant portion of the efforts to attain economical feasibility of the lignocellulose biomass processing and to conflict with chemicals and renewable vitality as well.[7]

Summary

Introduction

The activity of endo-1,4-b-xylanase produces non-reducing ends of xylooligosaccharides from which xylose is released by enzymatic action of b-xylosidases.[3] In this addendum, the optimization of the various parameters involved in the enhanced expression of recombinant xylanase enzyme as well as for the maximum saccharification of plant biomasses are discussed.

Results

Conclusion