固态厌氧发酵生棉粕降低游离棉酚含量的分析-analysis of reducing free gossypol content in raw cottonseed meal by solid anaerobic fermentation.docxVIP

PAGE PAGE IVAbstractChina is rich in cottonseed meal. Annual output is more than 6.0 million tons, ranking first in the world. Cottonseed meal is an important plant protein with high content of crudeprotein (38％-50％) and a large quantity of amino acid, only lysine is lower than that ofsoybean meal. Cottonseed meal also have plenty of anti-nutritional factors, such as free gossypol, Non-starch polysaccharides, phenolic acid, tannin etc. These anti-nutritional factors affect the palatability and the feed intake, decrease the effective availability of nutritional components, especially free gossypol products is toxic. When animal feed the diets with high content free gossypol, The animal body cell vascular, nerve will be destroyed, which leads to degeneration and necrosis of animal organs, dysfunction, and damages the spermatogenic epithelium, reduce animal reproductive ability and even cause infertility. Microbial fermentation can effectively remove the anti-nutritional factors and improve nutritional value of cottonseed meal. At present, more researches are aerobic fermentation of cottonseed meal. However, nutrient substances of cottonseed meal were serious loss in the aerobic fermentation process and autoclave processing will significantly affect its nutritional value. While researches on the anaerobic microbe in cottonseed meal fermentation process are related less. This study was carried out by Enterococcus faecalis EF-24 from the laboratory preserving strains with a good free gossypol degradation effect. Culture conditions of Enterococcus faecalis EF-24 were optimized and free gossypol in cottonseed meal was used as the main indicators to optimize their anaerobic fermentation conditions. the degradation mechanisms of free cotton phenol was explored.Screening and physiological and biochemical identification of the free gossypoldegradation strains. In order to obtain strain for degradation free gossypol in cottonseed meal, 22 strain preserved by the laboratory we