诱导发酵桦褐孔菌三萜类化合物合成及其抗氧化功能的研究

本文通过在桦褐孔菌液体发酵过程中加入外源诱导剂,探究其对桦褐孔菌菌丝体中三萜类化合物含量以及菌丝体醇提物抗氧化性的影响。结果表明:茉莉酸甲酯(MeJA)、水杨酸(Salicylic acid,SA)、亚油酸、桦树皮水提物、铁离子(Fe²⁺)5种诱导剂均能增加菌丝体中总三萜类化合物含量和提高其醇提物抗氧化能力。其中MeJA效果最佳,在第6 d加入50 μmol/L茉莉酸甲酯可得到菌丝体的量为(10.05±0.01) g/L,菌丝体中三萜含量(107.72±1.07) mg/g,三萜总量为1082.19 mg/L,与不加入诱导剂的对照组相比三萜总量增加了119.96%。抗氧化能力试验中,MeJA诱导的桦褐孔菌醇提物总还原力1.003,DPPH自由基、羟基自由基、超氧阴离子自由基的IC₅₀分别为0.091、1.657、0.024 mg/mL,与对照组相比总还原能力与各自由基清除率分别提高了46.67%、53.23%、32.17%和30.30%。本研究为诱导剂在提高桦褐孔菌三萜类化合物产量上以及开发新的抗氧化剂提供科学依据。

Study on the Synthesis and Antioxidant Function of Triterpenes from Inonotus obliquus Induced by Fermentation

The aim of this paper was to investigate the effects of exogenous inducers on the triterpenoid contents of Inonotus obliquus mycelium by liquid fermentation and the antioxidant activity of mycelium alcohol extracts.The results showed that:Methyl jasmonate (MeJA), salicylic acid (SA), linoleic acid, birch bark water extract, Fe2+ as inducers could increase the content of triterpenoids in mycelium and improve the antioxidant capacity of its isopropanol extracts. The effect of MeJA was the best. When 50 μmol/L was added in 6th day, the amount of mycelium was (10.05±0.01) g/L, and the average triterpene content of mycele was (107.72±1.07) mg/g and the total amount was 1082.19 mg/L. Compared with the control group without inducer, the total amount of triterpenes increased by 119.96%. In the antioxidant capacity test, the IC₅₀ of the total reducing power of 1.003, DPPH free radical, hydroxyl radical and superoxide anion radical induced by MeJA induced by MeJA was 0.091, 1.657, 0.024 mg/mL, respectively. Compared with the control group, the total reducing ability and the free radical scavenging rate were increased by 46.67%, 53.23%, 32.17% and 30.30%, respectively.The result can provide scientific basis for the application of inducers in increasing the yield of triterpenoids and develop new antioxidants.