Comparative production of xylanase and the liberation of xylooligosaccharides from lignocellulosic biomass by Aspergillus brasiliensis BLf1 and recombinant Aspergillus nidulans XynC A773

Abstract

Summary We investigated the simultaneous production of xylanase and the liberation of xylooligosaccharides in rice husk solid‐state cultivations of Aspergillus brasiliensis BLf1 and by the recombinant Aspergillus nidulans XynC A773 strain. The bioprocess was optimised by experimental fractional design and response surface analysis. Results show that both fungi strains produced xylanases and their activities were dependent on the addition of basal medium, moisture content and the interactions between particle size and inoculum size, producing maximum xylanase activities of 230.7 U g−1 substrate for A. brasiliensis, and 187.9 U g−1 substrate for A. nidulans XynC. Xylooligosaccharides were liberated in the same cultures, with concentrations up to 17.6 mg g−1 and 23.9 mg g−1 of substrate for A. brasiliensis and A. nidulans XynC, respectively, both strains presenting similar profiles, with xylose residues varying from X3 to X6. These results suggest the possibility of lowering production costs of enzymes for food applications and oligosaccharides.

Aspergillus nidulans: A Potential Resource of the Production of the Native and Heterologous Enzymes for Industrial Applications

“…[33]. da Silva Mennezes et al [23] carried out SSF of rice husk by Aspergillus nidulans XynC A773 and produced 187.9 U/g of xylanase.…”

“…e xylanase production was influenced by fermentation parameters such as basal medium, moisture content, and interactions between granulometry and inoculum size [23].…”

“…Gonçalves et al [22] studied biodiesel production from Acai (Euterpe oleracea Martius), Buriti (Mauritia flexuosa), and coffee grounds oils using recombinant lipase produced by A. nidulans. Transesterification reaction of coffee spent, Buriti, and Acai oils by immobilized lipase in Sepabead-C18 in the presence of ethanol was performed [23]. XOs have the advantage to be fermented by specific bacteria such as Bifidobacterium and Lactobacillus that act as probiotics [77][78][79].…”

“…SSF of rice husk was carried out by A. nidulans XynC A773 to produce xylanase and XOs. A. nidulans XynC A773 produced 23.9 mg/g of the substrate under SSF that is more concentrated and can be extracted easily compared to the diluted medium of submerged culture [23]. Gonçalves et al [25] studied the production of XOs from pretreated sugarcane bagasse by the synergic action of GH11 endoxylanase and GH54 arabinofuranosidase produced by A. nidulans [25].…”

“…Its physiology, morphology, and optimal growth conditions are well characterized [21][22][23]. In the last few years, several investigations have been performed on A. nidulans as a host organism for the production of different heterologous enzymes such as lipase [22], xylanase [23], xyloglucanase (GH12) [24], endoxylanase (GH11) [25], arabinofuranosidase (GH54) [25], and aryl alcohol oxidase [4]. e life cycle of A. nidulans progresses through both sexual and asexual reproduction stages.…”