二年残孔菌的培养条件优化及其液体发酵产物的抗氧化及漆酶活性

Culture condition optimization,antioxidant capacity,and laccase production of Abortiporus biennis

二年残孔菌(Abortiporus biennis)是一种具有抗氧化、抗肿瘤功效的药用白腐真菌,可降解木质素、造成木材白色腐朽.以分离自江苏无锡的二年残孔菌WX-02菌株为材料,开展菌丝最适培养条件、液体发酵产物抗氧化活性及Cu2+诱导产漆酶活性研究.基于单因子试验的最适生长条件结果表明,葡萄糖是WX-02菌株菌丝体生长的最适碳源,牛肉膏和黄豆粉为最适氮源,C/N比为40/1时长势最佳,玉米粉和VC为最适生长因子,而菌丝生长最适pH和温度分别为7.0和32℃10%(V/V)接种量、28℃、150 r/min培养72 h条件下,PD培养基发酵液的总抗氧化活性为2.76±0.31mmol/L(FeSO4)和0.40±0.01 mmol/L(Trolox),DPPH自由基清除率为100.00%±0.00%,总SOD活力为15.75±0.25 U/mL;最适培养条件液体培养基发酵液的总抗氧化活性为0.20±0.03mmol/L(FeSO4)和0.16±0.01 mmol/L(Trolox),DPPH自由基清除率为59.06%±0.61%,总SOD活力为15.65±0.62 U/mL. 0.25 mmol/L Cu2+对胞外漆酶诱导效果最佳,PD培养基、0.25 mmol/L Cu2+、28℃、150 r/min培养96 h,胞外漆酶活性最高,为(1.82±0.02)×105 U/mL,是对照组的1.72倍.本研究表明WX-02菌株具有良好的抗氧化和产漆酶活性,具有药用和环境治理开发应用潜能.(图4表4参34)

Abortiporus biennis is a medicinal white rot fungus with antioxidation and anti-tumor effects,which can degrade lignin and cause white decay of wood.In the present study,A.biennis strain WX-02 isolated from Wuxi,Jiangsu Province,was used as the study material.The optimal culture conditions for mycelia,antioxidant activities,and Cu2+-induced laccase production of liquid fermentation were investigated.Culture conditions based on single factor experiments revealed that the optimum carbon source for strain WX-02 mycelial growth was glucose,whereas the optimum nitrogen sources were beef extract and soybean powder.When the C/N ratio was 40/1,the mycelia demonstrated the highest growth vigor.The optimum growth factors were corn flour and vitamin C,and the optimal pH and temperature were 7.0 and 32℃respectively.With a 10%(V/V)inoculation concentration at 28℃and 150 r/min for 72 h,the fermentation broth using PD medium manifested a total antioxidant activity of 2.76±0.31 mmol/L(FeSO4)and 0.40±0.01 mmol/L(Trolox),DPPH radical scavenging ratio of 100.00±0.00%,and SOD activity of 15.75±0.25 U/mL.The fermentation broth using the optimum culture condition medium demonstrated a total antioxidant activity of 0.20±0.03 mmol/L(FeSO4)and 0.16±0.01 mmol/L(Trolox),DPPH radical scavenging ratio of 59.06±0.61%,and SOD activity of 15.65±0.62 U/mL.Further study of Cu2+on extracellular laccase production revealed that 0.25 mmol/L of Cu2+significantly enhanced the enzyme production with the highest activity of 1.82±0.02×105 U/mL after liquid fermentation at 28℃at 150 r/min for 96 h,which was 1.72 times higher than that of the control group.The WX-02 strain demonstrated considerably high antioxidant and laccase activities,suggesting its potential application in medicinal and environmental management.