Certain factors influencing the biodegradation of valonia tannin, ellagitannin, by Endomyces SHQ14 are investigated. The degradation rate of valonia tannin and removal of chemical oxygen demand (COD) are both maximized in a medium containing 25g.l(-1) valonia tannin by shaking the culture at 120 rpm and incubating it at 28 degrees C and pH 4.5-5 for 8 days. Additional carbon sources, particularly sucrose, support the degradation of valonia tannin. Peptone is found to be the most suitable nitrogen source. It is verified that the proper ratio of carbon (sucrose) to nitrogen (sodium nitrate) for the degradation of valonia tannin is about 10:1. Four kinds of compounds that may affect the degradation process were selected for this study; namely, an inducer 2,2'-azinobis (3-ethylbenzothiazolin-6-sulfonic acid) (ABTS), an inhibitor, EDTA and two surfactants SDS (sodium dodecylbenzene sulphonate) and Tween-80 (Tw-80). Note: Tween-80 is polyoxyethylene sorbitan monooleate ester with an HLB value of 14 which is used as an emulsifier / surfactant. The biodegradation process is found to be stimulated by 0.3 x 10(-3) M inducer ABTS and 0.2 g.l(-1) surfactant Tween-80 and SDS, but is inhibited by EDTA.
|Number of pages||6|
|Journal||Journal of the society of leather technologists and chemists|
|Publication status||Published - 2005|
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