Open AccessPurification and Properties of Acid Stable Xylanases fromAspergillus kawachii
Author(s) -
Kiyoshi Itō,
Hironobu Ogasawara,
Takashi Sugimoto,
Takahiro Ishikawa
Publication year - 1992
Publication title -
bioscience, biotechnology, and biochemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.509
H-Index - 116
eISSN - 1347-6947
pISSN - 0916-8451
DOI - 10.1271/bbb.56.547
Subject(s) - xylanase , xylobiose , xylose , xylan , chemistry , food science , biochemistry , hydrolysis , enzyme , fermentation
Five extracellular endo-xylanases were recognized in the culture broth of shochu koji mold (Aspergillus kawachii, IFO 4308), and three major xylanases (XylA, XylB, and XylC) were purified and characterized. The molecular masses of XylA, XylB, and XylC were 35,000, 26,000, and 29,000, and isoelectric points were pH 6.7, 4.4, and 3.5, respectively. Amino acid compositions and other properties were studied and these three xylanases were found to be greatly different in their properties. These three xylanases, XylA, XylB, and XylC, were stable between pH 3-10, 3-10, and 1-9 and the optimum pHs were 5.5, 4.5, and 2.0, respectively. Consequently, these xylanases were acid stable xylanases, especially XylC was an acidophilic xylanase (acid xylanase). These xylanases produced various xylooligosaccharides including xylose from xylan and the main product was xylobiose in all xylanases. The production of acid xylanase (XylC) was enhanced with a low initial pH of the medium.