Sudathip Chantorn, Chanitchote Piyapittayanun, Phataraporn Khumphai, Srisuda Pannanusorn, Kulwadee Phannachet, and Jirawan Apiraksakorn

DOI: 10.14456/sjst-psu.2016.24

pp. 177 - 182

Abstract

Bacillus sp. GA2(1) and Bacillus sp. GA1(6) were isolated from soybean field in Khon Kaen province, Thailand. Crude
enzymes from both isolates showed the activities of cellulase, xylanase, and mannanase at 37°C for 24 h. The highest xylanase
activities of Bacillus sp. GA2(1) and Bacillus sp. GA1(6) were 1.58±0.25 and 0.82±0.16 U/ml, respectively. The relative
xylanase activities from both strains were more than 60% at pH 5.0 to 8.0. The optimum temperature of xylanases was 50°C in
both strains. The residual xylanase activities from both strains were more than 70% at 60°C for 60 min. Five agricultural wastes
(AWs), namely coffee residue, soybean meal, potato peel, sugarcane bagasse, and corn cobs, were used as substrates for
hydrolysis properties. The highest reducing sugar content of 101±1.32 µg/ml was obtained from soybean meal hydrolysate
produced by Bacillus sp. GA2(1) xylanase.