玫红脉柄牛肝菌液体菌种培养基优化及胞外酶活性变化特征OA

The wild strain 2019MYKLR003 of Phlebopus roseus was used as the test material.Basic parameters for submerged culture were determined through single-factor experiments,and the medium formula was optimized using the response surface methodology.A high-activity induction formula was designed and verified,and the activity changes of peroxidase,laccase,and cellulase in mycelia under different fermentation conditions were determined.The results showed that this strain had a high oxygen demand for submerged culture and was highly sensitive to pH changes.The optimal pH value was 5 and liquid volume was 100 mL.The optimal medium formula(RA1)consisted of 432.35 g/L potato extract,2.00 g/L tryptone,and 32.47 g/L mannitol.The actual measured mycelial biomass increased by 130.21%as compared with the predicted value.The addition of 100 μg/mL VB1,50 μg/mL VB2,50 μg/mL VB3,and 5 g/L carboxymethyl cellulose to RA1 significantly alleviated mycelial browning and led to regular and uniform mycelial morphology.Adjusting the fermentation endpoint to 18 days could achieve the maximum mycelial biomass synthesis while ensuring the simultaneous highest activities of the three extracellular enzymes.This study provides a research reference for the standardized production of high-activity submerged spawn of P.roseus.