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The Incubation of 13a,17-Dihydroxystemodane with Cephalosporium aphidicola  [PDF]
Braulio M. Fraga,Ricardo Guillermo,Melchor G. Hernández,María C. Chamy,Juan A. Garbarino
Molecules , 2012, DOI: 10.3390/molecules17021744
Abstract: The biotransformation of 13a,17-dihydroxystemodane (3) with the fungus Cephalosporium aphidicola afforded 13a,17,18-trihydroxystemodane (4), 3b,13a,17-tri-hydroxystemodane (5), 13a,17-dihydroxy-stemodan-18-oic acid (6), 3b,11β,13a,17-tetra-hydroxystemodane (7), 11β,13a,17,18-tetrahydroxystemodane (8) and 3b,13a,17,18-tetra-hydroxystemodane (9). The hydroxylation at C-18 of the substrate points to a biosynthetically-directed transformation, because aphidicolin (2) is hydroxylated at this carbon. However, the C-3(b) and C-11(b) hydroxylations seem to indicate a xenobiotic biotransformation.
Di-And Tri-Hydroxylated Kaurane Derivatives From Microbial Transformation Of Ent-Kaur-16-En-19-Ol By Cephalosporium Aphidicola And Their Allelopathic Activity On Lactuca Sativa (Lettuce)
Rocha, D.;Takahashi, J. A.;Boaventura, M. A. D.;
Eclética Química , 2009, DOI: 10.1590/S0100-46702009000100009
Abstract: the use of microorganisms to induce chemical modifications in organic molecules is a very useful tool in organic synthesis, to obtain biologically active substances. the fungus cephalosporium aphidicola is known by its ability to hydroxylate several skeleton positions of many classes of organic compounds. in this work, the microbial transformation of ent-kaur-16-en-19-ol (1) by c. aphidicola, afforded two hydroxylated compounds, ent-kauran-16β,19-diol (2) and ent-kauran-16β,17,19-triol (3). their structures were established by 1d and 2d-nmr studies. both compounds were tested for their action on the growth of radical and shoot of lactuca sativa.
Purification and Characterization of a Mitogenic Lectin from Cephalosporium, a Pathogenic Fungus Causing Mycotic Keratitis  [PDF]
Nagaraja N. Nagre,Vishwanath B. Chachadi,Sachin M. Eligar,C. Shubhada,Radha Pujari,Padma Shastry,Bale M. Swamy,Shashikala R. Inamdar
Biochemistry Research International , 2010, DOI: 10.1155/2010/854656
Abstract: Ophthalmic mycoses caused by infectious fungi are being recognized as a serious concern since they lead to total blindness. Cephalosporium is one amongst several opportunistic fungal species implicated in ophthalmic infections leading to mycotic keratitis. A mitogenic lectin has been purified from the mycelia of fungus Cephalosporium, isolated from the corneal smears of a keratitis patient. Cephalosporium lectin (CSL) is a tetramer with subunit mass of 14 kDa, agglutinates human A, B, and O erythrocytes, and exhibits high affinity for mucin compared to fetuin and asialofetuin but does not bind to simple sugars indicating its complex sugar specificity. CSL showed strong binding to normal human peripheral blood mononuclear cells (PBMCs) to elicit mitogenic activity. The sugar specificity of the lectin and its interaction with PBMCs to exhibit mitogenic effect indicate its possible role in adhesion and infection process of Cephalosporium.
Purification and Characterization of a Mitogenic Lectin from Cephalosporium, a Pathogenic Fungus Causing Mycotic Keratitis  [PDF]
Nagaraja N. Nagre,Vishwanath B. Chachadi,Sachin M. Eligar,C. Shubhada,Radha Pujari,Padma Shastry,Bale M. Swamy,Shashikala R. Inamdar
Biochemistry Research International , 2010, DOI: 10.1155/2010/854656
Abstract: Ophthalmic mycoses caused by infectious fungi are being recognized as a serious concern since they lead to total blindness. Cephalosporium is one amongst several opportunistic fungal species implicated in ophthalmic infections leading to mycotic keratitis. A mitogenic lectin has been purified from the mycelia of fungus Cephalosporium, isolated from the corneal smears of a keratitis patient. Cephalosporium lectin (CSL) is a tetramer with subunit mass of 14?kDa, agglutinates human A, B, and O erythrocytes, and exhibits high affinity for mucin compared to fetuin and asialofetuin but does not bind to simple sugars indicating its complex sugar specificity. CSL showed strong binding to normal human peripheral blood mononuclear cells (PBMCs) to elicit mitogenic activity. The sugar specificity of the lectin and its interaction with PBMCs to exhibit mitogenic effect indicate its possible role in adhesion and infection process of Cephalosporium. 1. Introduction Ophthalmic infections caused by fungi rather than bacteria are of serious concern in many developing countries as they lead to blindness. Ocular fungal infections referred to as ophthalmic mycoses are leading to keratitis of the cornea [1]. Several fungal species responsible for mycotic keratitis and other forms of eye infections have been reviewed recently [2, 3]. Fusarium and Cephalosporium (Acremonium) are wide spread fungal species that belong to hyaline filamentous group which are implicated for ophthalmic mycoses [3]. The key factors involved in the pathogenesis of the mycotic keratitis include adherence, invasiveness, morphogenesis, and toxigenicity [4]. Fungal lectins are gaining importance as they are implicated in the process of specific recognition between fungal parasites and their host cells, involving protein-carbohydrate interactions leading to infection [5]. Lectins constitute a heterogeneous group of proteins of nonimmune origin with noncatalytic binding sites capable of recognizing and binding reversibly to specific carbohydrate moieties [6]. Although several reports are available on the lectins from higher fungi [7], very few lectins from animal and plant pathogenic fungi are reported [5, 8–13]. Further, fungal lectins are drawing greater attention as many of them exhibit interesting physiological effects such as lymphomitogenic activity, immunomodulatory effect, suppression of cell proliferation, and antitumor activity [14]. The present paper reports the purification, characterization, and mitogenic activity towards human PBMCs of a lectin from Cephalosporium, a pathogenic fungus,
A Novel Antioxidant Isobenzofuranone Derivative from Fungus Cephalosporium sp.AL031  [PDF]
Xiang-Zhong Huang,Yun Zhu,Xiao-Li Guan,Kai Tian,Jun-Ming Guo,Hong-Bin Wang,Guang-Miao Fu
Molecules , 2012, DOI: 10.3390/molecules17044219
Abstract: Bioassay-guided fractionation of metabolites from the fungus Cephalosporium sp.AL031 isolated from Sinarundinaria nitida led to the discovery of a new isobenzofuranone derivative, 4,6-dihydroxy-5-methoxy-7-methylphthalide (1), together with three known compounds: 4,5,6-trihydroxy-7-methyl-1,3-dihydroisobenzofuran (2), 4,6-dihydroxy-5-methoxy-7-methyl-1,3-dihydroisobenzofuran (3) and 4,5,6-trihydroxy-7-methylphthalide (4). The structure of the new compound 1 was determined based on MS, 1D and 2D NMR spectral data. Compounds 1–4 showed potent antioxidant activity with EC50 values of 10, 7, 22 and 5 μM by 1,1-diphenyl-2-picryhydrazyl (DPPH) radical-scavenging assay.
ENZYME SYSTEMS FROM THE THERMOPHILIC FUNGUS TALAROMYCES EMERSONII FOR SUGAR BEET BIOCONVERSION  [PDF]
Sara Fernandes,Patrick G Murray,Maria G. Tuohy
BioResources , 2008,
Abstract: The thermostable enzyme systems produced by the thermophilic ascomycete fungus Talaromyces emersonii cultivated on various carbon sources were investigated for the production of high value products from sugar beet. A broad range of enzymatic activities relevant to cellulose, hemicellulose, and pectin hydrolysis were identified in T. emersonii culture filtrates. In hydrolysis experiments conducted at 71oC, the enzyme cocktails generated sugar-rich syrups from untreated sugar beet plants. Maximal levels of sugar beet hydrolysis were obtained with T. emersonii enzyme cocktails induced with sorghum/ beet pulp (68%) and sugar beet plant (56%). The principle monosaccharides released were glucose, xylose, and arabinose with minor amounts of galactose and galacturonic acid. Northern analysis of RNA isolated from T. emersonii when sugar beet plants were used as the sole carbon inducing source showed that genes required for polysaccharide hydrolysis and five carbon monosaccharide metabolism were co-ordinately expressed.
Scopararanes C–G: New Oxygenated Pimarane Diterpenes from the Marine Sediment-Derived Fungus Eutypella scoparia FS26  [PDF]
Li Sun,Dongli Li,Meihua Tao,Yuchan Chen,Feijun Dan,Weimin Zhang
Marine Drugs , 2012, DOI: 10.3390/md10030539
Abstract: Five new oxygenated pimarane diterpenes, named scopararanes C–G ( 1– 5) were isolated from the culture of a marine sediment-derived fungus Eutypella scoparia FS26 obtained from the South China Sea. The structures of these compounds were established on the basis of extensive spectroscopic analysis. The absolute configurations of compounds 1– 5, were determined by CD spectroscopic analysis and comparison with literature data. All isolated compounds ( 1– 5) were evaluated for their cytotoxic activities against MCF-7, NCI-H460, and SF-268 tumor cell lines by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2 H-tetrazolium bromide (MTT) method.
Bioconversion of ferulic acid and 4-vinylguaiacol by a white-rot fungus isolated from decaying wood
LV Mabinya, T Mafunga, JM Brand
African Journal of Biotechnology , 2010,
Abstract: A white rot fungus isolated from decaying wood was investigated for its ability to convert ferulic acid to various valuable products. The fungus is able to convert ferulic acid to 4-vinylguaiacol, which is then metabolized further to acetovanillone. Both products have potential use in the chemical manufacturing and pharmaceutical industries and these results contribute to our knowledge of the biotransformation of ferulic acid.
Relationship between Incidence of Cephalosporium Stripe and Yield Loss in Winter Wheat  [PDF]
M. C. Quincke,C. J. Peterson,C. C. Mundt
International Journal of Agronomy , 2012, DOI: 10.1155/2012/635219
Abstract: Cephalosporium stripe (caused by Cephalosporium gramineum) can be a serious disease of winter wheat (Triticum aestivum L.) in the Pacific Northwest of the USA. Effects of Cephalosporium stripe on yield, test weight, protein, and kernel characteristics were examined using 12 winter wheat varieties in field plots inoculated and not inoculated with the pathogen. Averaged over varieties, inoculation decreased yield, test weight, kernel weight, and kernel diameter; grain protein and the standard deviations of kernel weight and kernel diameter were increased by inoculation. Grain yield of the susceptible check was reduced by as much as 41% with addition of inoculum. The most resistant and the most susceptible varieties performed similarly for yield in the two environments, while varieties with intermediate levels of resistance were sometimes inconsistent. There was a linear relationship between yield and % whiteheads (sterile heads caused by disease) in one environment and a curvilinear relation in the other. 1. Introduction Cephalosporium stripe of wheat is caused by the soil-borne fungal pathogen Cephalosporium gramineum Nisikado and Ikata (syn. Hymenula cerealis Ellis & Everh.) [1–3]. The fungus has a wide range of hosts, mainly among winter cereals [4, 5]. Cephalosporium stripe is of economic importance only in winter wheat, however. The disease is an important, limiting factor in many winter wheat production areas [6–9]. It is widespread throughout the Pacific Northwest of the USA, where wheat growers in erosion-prone areas are particularly affected when early plantings and reduced or no tillage are practiced [4, 10–12]. C. gramineum survives between host crops saprophytically as mycelium and conidia in association with host residues on or near the soil surface [13]. Infested crop residue is the primary source of inoculum. Conidia produced in the top layer of soil on crop stubble and released during cool and moist weather conditions during fall and winter are washed down into the root zone to infect the next crop [14, 15]. Once inside the roots, the fungus invades the vascular system and has the potential to colonize the entire plant. Successful establishment of C. gramineum inside the host is enhanced by the production of toxic metabolites that block the vascular system, thus preventing normal movement of water and nutrients [4, 11, 16]. The most typical and recognizable symptom, chlorotic leaf striping, is apparent on the younger, upper leaves during jointing and heading. Severely infected stems are stunted and prematurely ripen, producing a white and
Effects of microbial pretreatment of kenaf stalk by the white-rot fungus Pleurotus sajor-caju on bioconversion of fuel ethanol production
白腐真菌Pleurotus sajor-caju预处理对红麻秸秆发酵乙醇的影响

Qicheng Ruan,Jianmin Qi,Kaihui Hu,Pingping Fang,Haihong Lin,Jiantang Xu,Aifen Tao,Guolong Lin,Lifu Yi,
阮奇城
,祁建民,胡开辉,方平平,林海红,徐建堂,陶爱芬,林国龙,易利福

生物工程学报 , 2011,
Abstract: Kenaf stalk was pretreated by the white-rot fungus Pleurotus sajor-caju incubated in solid-state kenaf stalk cultivation medium. Delignification and subsequent enzymatic saccharification and fermentation of kenaf stalk were investigated in order to evaluate effects of microbial pretreatment on bioconversion of kenaf lignocellulose to fuel ethanol production. The highest delignification rate of 50.20% was obtained after 25?35 days cultivation by P. sajor-caju, which could improve subsequent enzymatic hydrolysis efficiency of kenaf cellulose. And the saccharification rate of pretreated kenaf stalk reached 69.33 to 78.64%, 4.5?5.1 times higher than the control. Simultaneous saccharification and fermentation (SSF) with microbial-pretreatment kenaf stalk as substrate was performed. The highest overall ethanol yield of 68.31% with 18.35 to 18.90 mg/mL was achieved after 72 h of SSF.
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