Xylan Decomposition in Plant Cell Walls as an Inducer of Surfactin Synthesis by Bacillus subtilis.

Marcin Łukaszewicz,Ida Szmigiel,Dorota Kwiatkowska,Anna Krasowska

doi:10.3390/biom11020239

Abstract

Hemicellulose is the second most abundant plant heterogenous biopolymer. Among products obtained from a wide range of agro-residues, biosurfactants, e.g., surfactin (SU), are gaining increasing interest. Our previous studies have shown that a Bacillus subtilis strain can successfully produce a significant amount of SU using a rapeseed cake. This work aimed to investigate plant hemicellulose components as substrates promoting SU’s efficient production by B. subtilis 87Y. Analyses of SU production, enzymatic activity and cell wall composition of hulled oat caryopses suggest that the main ingredients of plant hemicellulose, in particular xylan and its derivatives, may be responsible for an increased biosurfactant yield.

Highlights

Microbial hemi- and lignocellulosic hydrolysis of biomass has become increasingly important for reducing waste burden and for producing a variety of highvalue products [1,2,3,4]
We performed solid-state fermentation (SSF) on rapeseed meal (RSM) as control and compared the obtained results with SSF on RSM, a part of which was replaced by an increasing amount of milled oats (MO)
B. subtilis 87Y strain used in this study can successfully produce approximately 1.8 g of SU per kg of dry RSM (Figure 1A)

Summary

Introduction

Microbial hemi- and lignocellulosic hydrolysis of biomass has become increasingly important for reducing waste burden and for producing a variety of highvalue products [1,2,3,4]. Hemicellulose is the second most abundant plant heterogenous biopolymer. It is often composed of xylan [5,6], which has a backbone of β-(1→4)-linked xylose residues with side chains containing acetyl group, arabinose, or other sugars [7]. Among products obtained from a wide range of agro-residues, biosurfactants are gaining interest [10]. Biosurfactant surfactin (SU) is a well-known microbial-derived cyclic lipopeptide showing many useful properties. Our previous studies showed that Bacillus subtilis successfully produced SU in solid-state fermentation (SSF) on rapeseed cake [13]

Objectives

Methods

Results