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Chen Wanru Hu Yinzhong Wang Yu Huang Yuanrong College of Life Science,Hangzhou University,Hangzhou,

菌物学报 , 1995,
Abstract: Xylaria nigripes (Kl.) Sacc. is a well-known nourishing medicinal, fungus. It grows in the abandoned termite nest and is rare in the nature. This paper explores the nutrient conditions which effect the yields of the mycelia of Xylaria nigripes, measures the dynamic variation in the formation of the mycelia and polysaccharide of Xylaria nigripes, and examines the correlation between the characteristics of esterase isozyme and the polysaccharide contents of Xylaria nigripes. It is found that glucose, starch and fructose are the most suitable carbon sources, for the mycelia to grow. Peptone, peanut meal and soybean meal are found to be preferable nitrogen sources, with peanut meal or soybean meal better than peptone, and Mg++ and Zn++ the essential elements. Among several organic acids, only citric acid is found to promote the growth of the mycelia of Xylaria nigripes. Formic acid (pH = 4.0) constrains the growth of the mycelia of Xylaria nigripes, which is consistent with the fact that Xylaria nigripes do not .grow in the termite nest where formic acid is present. Based on the experiments mentioned above, we selected the suitable medium for producing the mycelia and polysaccharide with the biostatistic method. In the suitable medium, a dense suspension of Xylaria nigripes with numerous white homogeneous mycelia pellets and abundant polysaccharide is successfully produced. Under optimal conditions, the yields of polysaccharide reach 15.35g/L. and that of mycelia reach 26.8g/L in culture liquid within 4 days, which meets the requirement of industrial production. The esterase "isozyme patterns are stable and maintain 2 bands under different cultural conditions and growing stages. The esterase activity, however, is found to be correlated with the growing days of mycelia and the polysaccharide contents of Xylaria nigripes.
Single nucleotide polymorphisms of Xylaria nigripes

MA Cheng,CHEN Zuo-Hong,ZHANG Ping,

菌物学报 , 2011,
Abstract: To study the life cycle and genetic diversity of the ascomycete fungus Xylaria nigripes, single nucleotide polymorphisms (SNPs) were used as molecular marks. Based on the genomic library, a total of 193 SNPs were found in 34 fragments with 19,680bp from the two different individuals of X. nigripes, X-WC and X-LY, representing an SNP frequency of 0.981%. Among the 193 SNPs, all the sites had two alternative nucleotides, with 132 transitions and 61 transversions, resulting in a combined transition to transversion ratio of 2.16. The comparisons between the two individuals resulted in identification of 41 indels. Four of the 34 fragments were selected to examine intra-individual SNPs of the two individuals. Individual X-WC had an intra-individual SNP frequency of 1.308% (30/2293) per nucleotide and individual X-LY had a SNP frequency of 1.352% (31/2293) per nucleotide. Thirty-one sites double peak in the sequencing chromatograph indicated that the sclerotia of individual X-LY were heterokaryon.

Wu Genfu,Wu Xuechang,

微生物学报 , 2000,
Abstract: A strain belongs to Monascus sp. was separated from hongqu(Chinese beni-coji) which was used to brew red wine in Changxin county, Zhejiang province, and its DPPH radical scavenging metabolites were studied. Results showed that the yield and radical scavenging activity of neutral extract with EtOAc were higher than that of acid and basic extract. After shaken at 30 degrees C, 100 r/min for 5 days, this strain produced largest amount of neutral extract. Further partitioning the neutral fraction with silica gel column chromatograph, LH-20 column chromatograph, MPLC and HPLC, we screened 15 free radical scavengers whose yield was more than 2 mg and purity was higher than 85% in HPLC (260 nm absorption). Several of them were analyzed with 1H-NMR and 13C-NMR spectrum from which we concluded that B1-3 and C3-1-7 were two kinds of substitute of benzene, and C3-1-7 may be 3-OH-4-OCH3-benzoic acid. The scavenging activity of 40 mumol/L B1-3 was about 65%, and that of C3-1-7 was lower than 56%, while as the control the scavenging activity of 40 mumol/L Vc and Ve was 80.4% and 78.4% respectively.
Journal of the Chilean Chemical Society , 2012,
Abstract: Kinetics and stoichiometric measurements based on the reactions of stable free radicals are among the most employed procedures in the evaluation of antioxidant activities of pure compounds and complex mixtures. In the present work it is shown that initial rates of diphenyl-picryl hydrazyl (DPPH) consumption elicited by cinnamic acid derivatives are closely related to their reactivity towards peroxyl radicals. This implies that kinetic data regarding DPPH bleaching can be useful on the evaluation of antioxidant reactivities. On the other hand, data obtained at a single (long) reaction time are unrelated to the reactivity of the antioxidants and mostly reflect the number of phenol groups present in the tested sample.
The genus Xylaria from Maharashtra, India  [cached]
Indian Phytopathology , 2011,
Abstract: The present paper deals with the ten species of Xylaria collected from Mulashi forest, Western Ghats of Maharashtra, India. These include six new records from India. These are Xylaria beccari, X. cf. brevipes, X. oligotoma, X. schweinitzii, X. scruposa, X. feejeensis (= X. sp. aff. feejeensis). Although some of these species have been previously recorded, present collections showed remarkable morphological differences to the previously described ones.
Antioxidant activities of the methanolic extracts of four species of Ascomycetes

WU Shou-Hua,ZHANG Xiao-Jun,ZHANG Ping,CHEN Zuo-Hong,

菌物学报 , 2010,
Abstract: The methanol extracts of the mycelium (M) and fruiting body (F) of Cordyceps sinensis,Cordyceps gunnii,Cordyceps militaris and Xylaria nigripes were evaluated for their antioxidative activities using three different assays,1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity,reducing and chelating ability,and the content of total phenols.The results showed that the DPPH radical scavenging activity,reducing ability,and the content of total phenols of the fruiting bodies were significantly higher ...
Increasing the Efficiency of Energy Scavengers  [PDF]
Shahram M. Shahruz
Physics , 2007,
Abstract: In this paper, a methodology for designing efficient energy scavengers is proposed. The scavenger consists of a cantilever beam on which piezoelectric films and a mass are mounted. The mass at the tip of the beam is known as the proof mass and the device is called either an energy scavenger or a beam-mass system. The proof mass is a permanent magnet, where in its vicinity attracting permanent magnets are placed. It is shown that when the magnets have appropriate strengths and are placed appropriately, the vibration of the beam-mass system can be amplified, thereby the scavenged energy is increased. Examples are given throughout the paper.
Adiciones al conocimiento de Xylaria (Ascomycota, Xylariales) en México Additions to the knowledge of Xylaria (Ascomycota, Xylariales) in Mexico
Rosario Medel,Gastón Guzmán,Ranulfo Castillo
Revista mexicana de micología , 2010,
Abstract: A pesar de que se han publicado diversos trabajos sobre Xylaria en México, aún existen entidades del país con pocos registros de este género. El presente trabajo registra 18 especies de Xylaria de 15 entidades del país a saber: X. arbuscula, X. brevipes, X. corniculata, X. curta, X. enterogena, X. fockei, X. gracillima, X. guyanensis, X. hypoxylon, X. laevis, X. longipes, X. mellissi, X. microceras, X. multiplex, X. nigrescens, X. pallide.ostiolata, X. polymorpha yX. schweinitzii. Although several works have been published on Xylaria in Mexico, some states of the country have few records of this genus. The present work recorded 18 species of Xylaria from 15 states, the species are: X. arbuscula, X. brevipes, X. corniculata, X. curta, X. enterogena, X. fockei, X. gracillima, X. guyanensis, X. hypoxylon, X. laevis, X. longipes, X. mellissi, X. microceras, X. multiplex, X.nigrescens, X. pallide-ostiolata, X. polymorpha and X. schwenitzii.
Chemical investigation on the cultures of the fungus Xylaria carpophila
Xia Yin,Tao Feng,Zheng-Hui Li,Jia Su,Yan Li,Ning-Hua Tan,Ji-Kai Liu
Natural Products and Bioprospecting , 2011, DOI: 10.1007/s13659-011-0011-y
Abstract: A chemical investigation on the cultures of Xylaria carpophila led to the isolation of one known cyclopeptide cyclo(Nmethyl- l -Phe- l -Pro- l -Leu- d -Ile- l -Val) (1), five new sesquiterpenes, named as xylcarpins A–E (2–6), and another known compound (7). The structures were determined by extensive NMR and MS spectroscopic analysis. The absolute configuration of 1 was established by use of Marfey’s method and ROESY spectroscopic data. All compounds were tested for their cytotoxicities against five human cancer cell lines. Compound 7 showed week inhibitory activity.
Adiciones al conocimiento de Xylaria (Ascomycota, Xylariales) en México
Medel, Rosario;Guzmán, Gastón;Castillo, Ranulfo;
Revista mexicana de micología , 2010,
Abstract: although several works have been published on xylaria in mexico, some states of the country have few records of this genus. the present work recorded 18 species of xylaria from 15 states, the species are: x. arbuscula, x. brevipes, x. corniculata, x. curta, x. enterogena, x. fockei, x. gracillima, x. guyanensis, x. hypoxylon, x. laevis, x. longipes, x. mellissi, x. microceras, x. multiplex, x.nigrescens, x. pallide-ostiolata, x. polymorpha and x. schwenitzii.
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