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In this paper,the spawn was isolated from the stroma of Xylaria nigripes collected from wangcheng county in Hunan province and identified by means of ITS sequences,the fruiting body of Xylaria nigripes was cultivated successfully for the first time.Some active compounds including crude polysaccharide,mannitol,nucleotides and amino acids in different tissues(natural sclerotium,natural stroma,cultivated stroma and fermented mycelium) of Xylaria nigripes were determined by means of HPLC,UV spectrophotometry,amino acid analyzer and chemical reaction.The results are as follows:1.The spawn was isolated from the stroma of Xylaria nigripes and the ITS(internal transcribed spacer) sequences including ITS1,ITS2 and 5.8S rDNA gene of Xylaria nigripes from different original locations were determined and compared with other Xylaria species sequences from GeneBank.ITS sequences of different tissues(natural sclerotium, natural stroma,cultivated stroma and fermented mycelium) of Xylaria nigripes also were analyzed.The results showed that ITS sequences from the fermented mycelium and cultured mycelium which grew on the solid medium mycelium were in accord with that of Xylaria nigripes strain from Wangcheng county.It can be concluded that the isolated mycelium was mycelium of Xylaria nigripes.2.The best culture condition of Xylaria nigripes was screened out. The best medium was sawdust medium for the Cultivation condition of Xylaria nigripes and the best condition was in the dark at 25℃.The stroma of Xylaria nigripes was quite easy to form in the cultivation house under the condition of 25℃,85%relative humidity and natural light。3.The crude polysaccharide was isolated with hot water extraction, ehanol deposition and the content of crude polysaccharide in fermentative mycelium,cultured stroma,natural stroma and wild sclerotium was 1.76mg/g,1.66mg/g,1.45mg/g and 1.65mg/g respectively;the percentage of total polysaccharide in fermentative mycelium,cultured stroma,wild stroma,and wild sclerotium was 20.60%,25.85%,20.15%,23.65%respectively.4.the mannitol is rich in Xylaria nigripes.The mannitol content in fermentative mycelium,cultivated strome,wild stroma,wild sclerotium was 75.0,65.0,36.5 and 41.3mg/g respectively.5.The kinds and content of nucleosides in different tissues(natural sclerotium,natural stroma,cultivated stroma and fermented mycelium) were determined by means of high performance liquid chromatography (HPLC).The results showed that the content of uridine in the fermental mycelia,cultured stroma,natural stroma and sclerotium was 1120.15, 2078.46,2305.01 and 340.43μg/g,respectively;the adenosine was 1156.19,1886.19,2423.45and 909.72μg/g,respectively.Besides,two other unknown nucleosides which the content were comparatively high were discovered and further research is needed.6.The constituents and contents of hydrolytic and free amino acid in different tissues(natural sclerotium,natural stroma,cultivated stroma and fermented mycelium) of Xylaria nigripes were determinated by automatic amino acid analysator L-8800.The results showed that there were 17 kinds of hydrolytic amino acid(7 kinds of essential amino acids) and 29 kinds of free amino acid(8 kinds of essential amino acids) in different tissues of Xylaria nigripes.The total content of hydrolytic amino acid was 121.521～271.594(mg/g),the E/T was 39.87～57.60%.The cultivated stroma had the highest contents of total amino acids and essential amino acids,whereas the natural stroma had the lowest contents of total amino acids and essential amino acids.
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