秦巴山区低温型香菇的硒耐受力及富硒液体培养基优化

考察秦巴山区低温型香菇的硒耐受力,优化其在富硒条件下的培养基配方,拟为富硒香菇的相关产品开发提供参考依据。以秦巴山区规模化栽培的低温型香菇9608#菌株为试材,根据菌丝平均生长速度筛选其耐受Na₂Se O₃的最佳浓度;以菌丝体生物量为主要指标,通过Plackett-Burman实验、最陡爬坡实验、Box-Behnken响应面实验及验证实验,研究香菇9608#菌株最优的富硒液体培养基。结果表明,香菇9608#菌株耐受Na₂Se O₃的最佳浓度为20.00 mg/L,其最佳富硒液体培养基为:马铃薯288.78 g/L、麦麸64.56 g/L、麦芽糖15.00 g/L、酵母膏10.00 g/L、KH2PO40.80 g/L、Mg SO₄·7H₂O 2.00 g/L、Na₂Se O₃20.00 mg/L。以此培养基对实验结果进行验证,菌丝生物量可达66.34 g/L,实测值与拟合值相比,相对误差约为2.05%,说明本研究方法可行、结论可靠。 

Optimization of fermentation conditions for Glutamic acid production by mixed starter cultures in solid state fermentation

The fermentation conditions for Glutamic acid production by a mixed starter culture composed of Aspergillus oryzae and Monascus purpureus in solid state fermentation were optimized. The effects of fermentation time, fermentation temperature, medium initial p H and moisture content on Glutamic acid were studied by single factor and orthogonal array design methods.Results suggested that the optimal fermentation conditions were the fermentation temperature 32 ℃, the fermentation time 5 d, the initial p H of fermentation medium 6 and the moisture content in medium 30%. Under these conditions, the yields of Glutamic acid and total amino acids were 194.2 g/kg and 768.5 g/kg, respectively, which were increased by 15.7% and 5.5%respectively compared to that before optimization.