A Study On Taxonomy Of Resupinate Inonotus, Liquid Culture And Chemical Composition Of Two Species In The Genus

Inonotus P. Karst. is one of the largest genera of Hymenochaetales, with rich divesity world-wide, and some species have high medicinal value. The taxonomy of resupinate Inonotus and their resource and distribution in China were studied. Moreover, the liquid culture of medicinal fungus-Inonotus lonicericola (Parmasto) Y.C. Dai and the chemical composition of another medicinal fungus-I. zonatus Y.C. Dai&X.M. Tian were studied, separately. The results are the following:About42species of Inonotus have been reported in China till now. Among them, ten were resupate fruiting body species, including I. andersonii (Ellis&Everh.) Cerny,I. henanensis Juan Li&Y.C. Dai,I. indurescens Y.C. Dai,I. magnisetus Y.C. Dai,I. niveomarginatus H.Y. Yu, C.L. Zhao&Y.C. Dai,I. obliquus, I. perchocolatus Corner,I. pruinosus Bondartsev,I. rigidus B.K. Cui&Y.C. Dai and I. tenuissimus H.Y. Yu, C.L Zhao&Y.C. Dai respectively. Two taxa of I. niveomarginatus and I. tenuissimus were described as new species in this study. Inonotus niveomarginatus is characterized by resupinate basidiocarps with distinct white margins, a monomitic hyphal structure, absence of hymenial and hyphoid setae, and yellowish, thick-walle, ovoid to subglobose basidiospores. Inonotus tenuissimus can be distinguished from other Inonotus species by the combination of resupinate habit, a mono-to dimitic hyphal structure, absence of the hymenial and hyphoid setae, and yellowish thick-walled ellipsoid basidiospores.In the liquid culture of Inonotus lonicericola, the mycelium bio mass was highest on the medium of glucose as the carbon source, and relatively low in the medium of xylose and sucrose as carbon source. In addition, the mycelium biomass was higher in the organic nitrogen source than those in the inorganic nitrogen, and the growth was nearly stopped with urea, potassium nitrate, ammonium sulfate medium. During the cultivation in shaked liquid medium (volume=250mL) of I.lonicericola, the mycelial biomass was highest at168-216h as8.33g L-1; the pH value of the medium decreased from5.36at24h to4.36at48h, and then it becamestable at value around4.0. The intracellular and extracellular polyphenolic content were changed in the culture process:extracellular polyphenol (EP) content reached a maximum level at168h, and then decreased slowly; the intracellular polyphenol (IP) increased slowly and reached a maximum value at192h and then decreased slowly. In addition,24h light slightly inhibited the growth of mycelia, but promoted the formation of IP and EP, and inhibition of DPPH radical. The initial culture medium of pH5.3was the best for the increase of mycelial biomass, the IP and EP content, and antioxidant activities against DPPH radical. In the initial culture of pH10.0, the mycelial growth and the generation of EP and IP were inhibited.In the study of chemical composition of Inonotus zonatus,12compounds were isolatied from the fermentation products. Their structures were identified as palmitic acid (1), methyl linoleate (2),(Z)-6-acetyl-3-(l,2-dihydroxypropylidene)-5-hydroxy-8-methylchroman-2-one (3),7,8-dimethylbenzo[g]pteridine-2,4(1H,3H)-dione (4),5:5’-diacetyl-2:6:2’:6’-tetrahydroxy-3:3’-dimethyldiphenylmethane (5), Cyclic dipeptide (Leu-VAL)(6),(22E,24R)-Ergosta-7,22-dien-3β-o1(7), ergosterol peroxide (8),(22E,24R)-Ergosta-7,22-diene-3β,5α,6β-triol (9),(Z or E)3-Methylpent-2-en-1,5-dioic acid (10and11) and Penilactone A (14).