Xylan from bambara and cowpea biomass and their structural elucidation

Nanthakumar Arumugam; Peter Biely; Vladimír Puchart; Abe Shegro Gerrano; Koel De Mukherjee; Suren Singh; Santhosh Pillai

doi:10.1016/j.ijbiomac.2019.04.030

Xylan from bambara and cowpea biomass and their structural elucidation

Int J Biol Macromol. 2019 Jul 1:132:987-993. doi: 10.1016/j.ijbiomac.2019.04.030. Epub 2019 Apr 5.

Authors

Nanthakumar Arumugam¹, Peter Biely², Vladimír Puchart², Abe Shegro Gerrano³, Koel De Mukherjee⁴, Suren Singh⁴, Santhosh Pillai⁵

Affiliations

¹ Department of Biotechnology and Food Technology, Faculty of Applied Sciences, Durban University of Technology, PO BOX 1334, Durban 4000, South Africa; Institute of Chemistry, Slovak Academy of Sciences, Dúbravská cesta 9, SK-845 38 Bratislava, Slovak Republic.
² Institute of Chemistry, Slovak Academy of Sciences, Dúbravská cesta 9, SK-845 38 Bratislava, Slovak Republic.
³ Agricultural Research Council-Vegetable and Ornamental Plant Institute, Pretoria, South Africa.
⁴ Department of Biotechnology and Food Technology, Faculty of Applied Sciences, Durban University of Technology, PO BOX 1334, Durban 4000, South Africa.
⁵ Department of Biotechnology and Food Technology, Faculty of Applied Sciences, Durban University of Technology, PO BOX 1334, Durban 4000, South Africa. Electronic address: santhoshk@dut.ac.za.

PMID: 30959129
DOI: 10.1016/j.ijbiomac.2019.04.030

Abstract

This work is the first report on the isolation and structural elucidation of xylan from bambara and cowpea biomass. The xylans, isolated using acidic delignification followed by NaOH extraction method gave 12.3% and 13.6% yield, respectively. ¹H NMR analyses revealed that both the xylans were glucuronoxylan. The presence of xylose and glucuronic acid was confirmed by monosaccharide analysis and uronic acid assay. Further, xylooligosaccharide production from bambara and cowpea xylans was carried out using xylanase from three different glycoside hydrolase families, and the products were analyzed by TLC and MALDI-ToF MS. The hydrolysis products of both xylans resembled hardwood glucuronoxylan fragments, generated under similar conditions. The most common oligosaccharides observed in the hydrolysates were Xyl₂, Xyl₃, MeGlcA³Xyl₃, MeGlcAXyl₄ and MeGlcAXyl₅. A series of computational approaches were also used to study the interactions of the three different xylanases with xylan. Thus, untapped biomass such as bambara and cowpea could serve as a potential source for xylan which could further be converted to xylooligosaccharides and many other value-added chemicals.

Keywords: Docking; Enzymatic hydrolysis; MALDI-ToF MS; NMR spectroscopy; Xylan; Xylooligosaccharides.

MeSH terms

Biomass*
Computer Simulation
Endo-1,4-beta Xylanases / chemistry
Endo-1,4-beta Xylanases / metabolism
Molecular Docking Simulation
Protein Conformation
Vigna / chemistry*
Xylans / chemistry*
Xylans / metabolism

Substances

Xylans
Endo-1,4-beta Xylanases