99A-20 |
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H. M. EL-SAIED, S. A. Gabr, A. S. Hamed, and H. T. M. Hefnawy. Dept. of Biochemistry, Zagzig Univ. of Egypt, Facultyof Agriculture, 18 Yamen St., Lebnanon Sq., Mohandsean, Cairo, Egypt Xanthan gum is a microbial polysaccharide obtained by the bacteria Xanthomonas campestris ,and has excellent rheological properties. It can be used as stabilizer, and thickener agents in food and pharmaceutical industries. Also it can be used as an emulsifier, lubricant, thickening agents. Our objective was to produce xanthan gum using some industrial and agriculture by-products,as carbon sources in the fermentation medium of the organism Xanthomonas campestris NRRL-B-1499 using shake flasks 250 ml and rotary agitation 200 r.p.m. for up to 168 hrs. at 30C.The xanthan yield was expressed as gm.(dry weight)L. medium. Each of sugar can molasses, sweat whey, permeat whey, brekly pear shells, tomato pomace, pea pods, orange pulp and grape pomace, were used as carbon source in the fermentation medium in different concentrations 1-6%. The optimum concentration of all these carbon sources was 4% in the fermentation and the optimum fermentation period was 144 hrs. Grape pomace in the medium gave the highest xanthan yield 9.3g/L and molasses gave the second one 7.95g/L,while pea pods gave the lowest yield 2.18g/L. Each of brekly pear shells, sweet whey, permeate whey, orange pulp, tomato pomace, gave xanthan yield as follows respectively 7.1,6.39,5.96,5.5,3.86g/L. Moreover the primary analysis of the tested industrial and agriculture by-products were included.
Session 99A, Biotechnology: General
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