Document Type : Original Article
Authors
1
Botany and Microbiology Department, Faculty of Science, Benha University, Benha, Egypt.
2
Microbial Biotechnology Department, Biotechnology Research Institute, National Research Centre, El-Buhouth St. 33, Dokki, Cairo, Egypt.
3
Molecular Biology Department, National Research Centre, 33-El Bohouth St., Dokki, Giza, P.O.12622, Egypt.
Abstract
Xylan is recognized as the primary constituent of plant hemicelluloses and holds potential as a
suitable initial material for synthesizing a range of artificial compounds and mixtures. Following
cellulose, xylan ranks as the second most abundant polysaccharide found in the natural
environment. The extraction of xylooligosaccharides from heteroxylans is achieved through both
chemical and enzymatic approaches, with the latter method offering several advantages such as
precision, substitution pattern and linkage type specificity, reaction manipulation, and elevated
reaction rates. Xylanase is an innate enzyme present in organisms and fungi, falling under the
category of pentosanases—an enzyme group used for breaking down plant cell wall matrices
through xylan hydrolysis into xylose. Consequently, this inherent characteristic of the xylanase
enzyme has bestowed it with commercial significance. Xylanases, classified as glucosidases (Oglycoside hydrolases, EC 3.2.1.x), facilitate the endo hydrolysis of 1,4-β-D-glycosidic bonds within
xylan molecules. Among the most noteworthy xylanolytic microorganisms are Aspergilli,
Trichoderma, streptomycetes, Bacilli, and others. In this investigation, twenty-one streptomycete
isolates were obtained from various locations across Egypt and subjected to quantitative screening
for xylanase production. The most potent isolate, Streptomyces (C5), was isolated from the Cairo
region. Xylan and sodium nitrate were identified as effective carbon and nitrogen sources,
respectively. The optimal pH for xylanase activity was determined to be 7, with an ideal
temperature of 30°C, and an incubation period of seven days.
Keywords