Anaerobic solid-state fermentation with Bacillus subtilis for digesting free gossypol and improving nutritional quality in cottonseed meal

作者：Jia Li, Tongguo Gao, Zhimin Hao, Xiaojun Guo, Baocheng Zhu · 发表于：Frontiers in Nutrition · 年份：2022 · DOI：10.3389/fnut.2022.1017637 · 被引用次数：42 · 研究领域：Research in Cotton Cultivation、Rice Cultivation and Yield Improvement、Agriculture, Land Use, Rural Development

Microbial fermentation is an effective method to degrade free-gossypol, which is a toxic substance restricting the utilization of cottonseed meal in animal husbandry. However, there are few researches on the nutritional effect and the change of bacterial community on cottonseed meal fermented with anaerobic solid-state fermentation. This study evaluated the effects of fermentation with Bacillus sp. on gossypol degradation and nutritional quality improvement in cottonseed meal (CM), as well as the changes of bacterial community structure during fermentation. The strains with high activity for digesting free gossypol were screened from high protease-producing strains preserved in the laboratory. Then the strains which had both the gossypol degradation activity and protease producing activity were selected to degrade macromolecular protein and free gossypol in CM. The unsterilized SSF medium was inoculated with 10 9 CFU/kg Bacillus culture and fermented at room temperature for 14 days. Each group had three parallels. And the effects of anaerobic solid-state fermentation on unsterilized CM was evaluated. Results showed that for the seven strains with high activity for digesting free gossypol and producing protease that were screened, free gossypol content in fermented cottonseed meal (FCM) decreased and acid-soluble protein (ASP) contents increased. Among them, strain M-15 had the best fermentation effect, with the free gossypol degradation rate of 93.46% and acid soluble protein...