title: Oxalic acid and sclerotial differentiation of Polyporus umbellatus.
abstract: The present investigation aimed to uncover the effects of exogenous oxalic acid during the sclerotial formation of Polyporus umbellatus, with an emphasis on determining the content of the endogenic oxalic acid in the fungus. To this end, the oxalic acid content of the vegetative mycelia, sclerotia, culture mediums and sclerotial exudate were measured using High Performance Liquid Chromatography (HPLC). Furthermore, the lipid peroxidation was estimated by detecting thiobarbituric bituric acid reactive substances (TBARS). The results showed that the exogenous oxalic acid caused a delay in sclerotial differentiation (of up to 9 or more days), suppressed the sclerotial biomass and decreased the lipid peroxidation significantly in a concentration-dependent manner. Oxalic acid was found at very low levels in the mycelia and the maltose medium, whereas it was found at high levels in the mycelia and sucrose medium. After sclerotial differentiation, oxalic acid accumulated at high levels in both the sclerotia and the sclerotial exudate. Oxalic acid was therefore found to inhibit P. umbellatus sclerotial formation.
authors.affiliation: Key Laboratory of Bioactive Substances and Resource Utilization of Chinese Herbal Medicine, Ministry of Education, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences &Peking Union Medical College, No. 151, Malianwa North Road, Haidian District, Beijing, P. R. China 100193.
authors.forename: Yong-Mei
authors.initials: YM
authors.lastname: Xing
authors.affiliation: 1] Key Laboratory of Bioactive Substances and Resource Utilization of Chinese Herbal Medicine, Ministry of Education, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences &Peking Union Medical College, No. 151, Malianwa North Road, Haidian District, Beijing, P. R. China 100193 [2] School of Biological Engineering, Tianjin University of Science &Technology, No.29, 13th Avenue, Tianjin Economic and Technological Development Area (TEDA), Tianjin, China 300457.
authors.forename: Wan-Qiang
authors.initials: WQ
authors.lastname: Yin
authors.affiliation: Key Laboratory of Bioactive Substances and Resource Utilization of Chinese Herbal Medicine, Ministry of Education, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences &Peking Union Medical College, No. 151, Malianwa North Road, Haidian District, Beijing, P. R. China 100193.
authors.forename: Meng-Meng
authors.initials: MM
authors.lastname: Liu
authors.affiliation: Key Laboratory of Bioactive Substances and Resource Utilization of Chinese Herbal Medicine, Ministry of Education, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences &Peking Union Medical College, No. 151, Malianwa North Road, Haidian District, Beijing, P. R. China 100193.
authors.forename: Chun-Lan
authors.initials: CL
authors.lastname: Wang
authors.affiliation: Key Laboratory of Bioactive Substances and Resource Utilization of Chinese Herbal Medicine, Ministry of Education, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences &Peking Union Medical College, No. 151, Malianwa North Road, Haidian District, Beijing, P. R. China 100193.
authors.forename: Shun-Xing
authors.initials: SX
authors.lastname: Guo
mesh_terms: D003470:Culture Media; D015227:Lipid Peroxidation; D025282:Mycelium; D019815:Oxalic Acid / Q000378:metabolism* / Q000494:pharmacology; D055492:Polyporus / Q000187:drug effects / Q000378:metabolism*; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism
chemical_list: D003470:Culture Media; D017392:Thiobarbituric Acid Reactive Substances; D019815:Oxalic Acid