کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
8334561 1540270 2012 10 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Alkaline xylanases from Bacillus mojavensis A21: Production and generation of xylooligosaccharides
موضوعات مرتبط
علوم زیستی و بیوفناوری بیوشیمی، ژنتیک و زیست شناسی مولکولی زیست شیمی
پیش نمایش صفحه اول مقاله
Alkaline xylanases from Bacillus mojavensis A21: Production and generation of xylooligosaccharides
چکیده انگلیسی
Medium composition and culture conditions for the xylanases production by Bacillus mojavensis A21 were optimized using two statistical methods: Plackett-Burman design applied to find the key ingredients and conditions for the best yield of enzyme production and Box-Behnken design used to optimize the value of the four significant variables: barley bran, NaCl, agitation, and cultivation time. The optimal conditions for higher production of xylanases were barley bran 18.66 g/l, NaCl 1.04 g/l, speed of agitation 176 rpm and cultivation time 34.08 h. Under these conditions, the xylanase experimental yield (7.45 U/ml) closely matched the yield predicted by the statistical model (7.23 U/ml) with R2 = 0.98. The medium optimization resulted in a 6.83-fold increase in xylanase production compared to that of the initial medium. Best xylanase activity was observed at the temperature of 50 °C and at pH 8.0. The enzyme retained more 96% of its activity after 24 h at pH ranges from 7.0 to 90.0. The enzyme preserved more 80% of its initial activity after 60 min of pre-incubation from 30 °C to 60 °C. The main hydrolysis products yielded from corncob extracted xylan were xylobiose and xylotriose, suggesting the good potential of strain A21 in xylooligosaccharides production.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: International Journal of Biological Macromolecules - Volume 51, Issue 4, November 2012, Pages 647-656
نویسندگان
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