title: Accumulation of antioxidant phenolic constituents in submerged cultures of Inonotus obliquus.
abstract: Phenolic compounds produced by sclerotia of Inonotus obliquus are the active constituents responsible for antioxidant activities. In this study, I. obliquus was grown in a continuously stirred tank reactor (CSTR) to explore how it accumulates phenolic compounds in different culture media and whether these compounds possess antioxidant activities. Phenolic compounds produced by I. obliquus in the control medium consisted of melanins, flavonoids, polyphenols and small phenolics. Their accumulation was affected by adding H(2)O(2) to the medium, where increased levels of total intracellular phenols (TIP) and melanins, but less total extracellular phenol (TEP) occurred. Simultaneous exposure to H(2)O(2) and arbutin resulted in a further increase in TIP production and reduced accumulation of TEP. Both TIP and TEP obtained at different culture ages and media were active in scavenging superoxide anion and DPPH radicals. Therefore, production of phenolic compounds by I. obliquus is enhanced by imposing oxidative stress, which might allow it to be exploited as a reliable source of pharmaceutically important phenolic compounds.
authors.affiliation: Key Laboratory for Biotechnology on Medicinal Plants of Jiangsu Province, Xuzhou Normal University, Xuzhou, China. yyzw@xznu.edu.cn
authors.forename: Weifa
authors.initials: W
authors.lastname: Zheng
authors.forename: Meimei
authors.initials: M
authors.lastname: Zhang
authors.forename: Yanxia
authors.initials: Y
authors.lastname: Zhao
authors.forename: Yao
authors.initials: Y
authors.lastname: Wang
authors.forename: Kangjie
authors.initials: K
authors.lastname: Miao
authors.forename: Zhiwen
authors.initials: Z
authors.lastname: Wei
mesh_terms: D000975:Antioxidants / Q000302:isolation & purification / Q000378:metabolism*; D001487:Basidiomycota / Q000378:metabolism*; D019149:Bioreactors / Q000382:microbiology*; D018929:Cell Culture Techniques / Q000379:methods*; D010636:Phenols / Q000302:isolation & purification / Q000378:metabolism*
chemical_list: D000975:Antioxidants; D010636:Phenols