一氧化氮对桦褐孔菌抗氧化酚类化合物积累的影响

本研究探讨了NO对深层培养的桦褐孔菌积累抗氧化酚类化合物的影响。在桦褐孔菌的培养基中分别加入0.01mmol/L、0.1mmol/L以及1mmol/L的NO供体硝普钠,并测定总酚的含量及其抗氧化活性。发酵产物的抗氧化活性以清除DPPH和羟自由基活力表示。加入0.1mmol/L的硝普钠可使桦褐孔菌胞内外酚类化合物分别达到最高水平67mg/g和677mg/L。不同培养时期产生的胞内外酚类化合物都具有抗氧化活性,尤其是添加0.1mmol/L硝普钠的菌丝体。因此NO可用于上调深层发酵培养的桦褐孔菌酚类化合物的积累。

Effects of nitric oxide on production of antioxidant phenolic compounds in Phaeoporus obliquus

This study was designed to evaluate the effects of nitric oxide (NO) on the production of phenolic compounds by Phaeoporus obliquus in submerged cultures and their subsequent antioxidant activities. NO was supplemented to the cultures in the form of sodium nitroprusside (SNP) at final concentrations of 0.01mmol/L, 0.1mmol/L and 1mmol/L, respectively, and total phenolic compounds and their subsequent antioxidant activities were determined. Antioxidant activity was expressed as potentials for scavenging DPPH and hydroxyl radicals. The exposure of P. obliquus to SNP at a final concentration of 0.1mmol/L resulted in a highest production of total intracellular and exocellular phenolic compounds, with levels reaching 67.00mg/g and 677.00mg/L, respectively. Both intra- and extracellular phenolic compounds produced at different culture ages all possessed antioxidant activities with higher levels seen in the cultures supplemented with SNP at a concentration of 0.1mmol/L. Thus NO can possibly be used for up-regulating accumulation of phenolic compounds in submerged cultures of P. obliquus.