Study On The Conversion Of 16α,17α-epoxyprogesterone By Metarhizium Anisopliae

This topic mainly tested one kind newly 16α,17α- epoxyprogesterone transformation mold - Metarhizium anisopliae. First the way of directly throwing the substrate was used to carry on the attempt, and the optimization of fermentation condition was acquired . The hydroxyl ability of Metarhizium anisopliae is very strong. The conversion rate in shake-flask can achieve about70% at 2% substrate density, but enlargeing in the 100L fermentation tank cann't achieve the expectation the conversion rate, only about 40%. Dissolved oxygen concentration only has 3% dissolved oxygen degree of saturation at the time of adding the substrate. Dissolved oxygen is the primary factor of limiting the strain transforming ability.In order to improve dissolvd oxygen, resting cell transformation craft was studied. Through optimizating the transformation condition, superior parameter of resting cell craft was acquired:by 1% quantity vaccination in the shake-flask seed fermentation medium, raised about 40h at 28℃and 180r/min. Adding 5% seed fermentation fluid in two levels of culture medium, raised it about 23h at the same fermentation condition,and than filtered the 120ml fermentation fluid , added mold mycelium in the 100ml cushion solution, continues to transform 30h at 30°C. The conversion rate was about 60%. Afterwards enlarges in the 100L fermentation tank, the conversion rate was about 45%.By the adding inhibitor, the reduced nutrition and the dilution mycelium, we wanted to solves the biomass and the conversion rate question. Discovery adding 1% ethyl alcohol at inoculation may have the certain reduced function to the biomass. But most mainly had the function which can promote transformation. The dilution mycelium may effectively reduce the biomass, the conversion rate also droped few.The optimization and the supplement to the dilution mycelium is carried on, and formed the mycelium dilution and fed nutrition material process. The process parameter was 1% quantity vaccination in the shake-flask ,raised 48h at 28℃and 180r/min. Added the aseptic water to dilution fermentation fluid according to 1: 1 quantity. Then fed 2% substrate at 8h and 20h, add 0.5% glucose and 0.05% ammonia water at 34h, and endded fermentation at oxidizing 64h. The biomass maintains at 10-15 g/l, can achieve about 72% in the shake-flask conversion rate. Afterwards enlarging process in the 100L fermentation tank, the conversion rate was about 53%.