Glioclatine, a novel epidithiodioxopiperazine was isolated from wheat solid-substrate fermentation of Gliocladium roseum YMF1.00133. Its structure was elucidated by HRESI-MS and NMR spectra.
Three compounds were obtained from the mycelia of an endophytic fungus Gliocladium sp. (designated as strain F) of Taxus chinensis (Pilg.) Rehd. growing in Fujian Province, China. Their structures were determined on t...Three compounds were obtained from the mycelia of an endophytic fungus Gliocladium sp. (designated as strain F) of Taxus chinensis (Pilg.) Rehd. growing in Fujian Province, China. Their structures were determined on the basis of spectral analysis. (20S,22S)-4a-homo-22-hydroxy-4-oxaergosta-7,24(28)-dien-3-one was a novel compound. 4,8,12,16-tetramethyl-1,5,9,13-tetraoxacyclohexadecane-2,6,10,14-tetraone was firstly isolated from the genus ofGliocladium and 6,9-epoxyergosta-7,22-dien-3-ol was firstly obtained from the strain F.展开更多
The present study was designed to explore the substrate scope and biocatalytic capability of Gliocladium deliquescens NRRL 1086 on phenolic natural products. Emodin was subjected to the fermentation culture of Gliocla...The present study was designed to explore the substrate scope and biocatalytic capability of Gliocladium deliquescens NRRL 1086 on phenolic natural products. Emodin was subjected to the fermentation culture of Gliocladium deliquescens NRRL 1086 according to the standard two-stage protocol. The biotransformation process was monitored by HPLC-DAD-MS, the main product was isolated by column chromatography, and the structure was elucidated on the basis of NMR spectroscopy. Emodin could be fully metabolized by Gliocladium deliquescens NRRL 1086, resulting in high yield of emodin 6-O-β-D-glucopyranoside and small amount of sulfated product. In conclusion, our results may provide a convenient method to prepare emodin 6-O-β-D-glucopyranoside and the microbe catalyzed glucosylation/sulfation will give an inspiration to pharmacokinetic model studies in vitro.展开更多
With an attempt to synthesize high-value isoquercitrin(quercetin-3-O-β-D-glucopyranoside), we carried out the biotransformation of quercetin(1) by Gliocladium deliquescens NRRL 1086. Along with the aimed product quer...With an attempt to synthesize high-value isoquercitrin(quercetin-3-O-β-D-glucopyranoside), we carried out the biotransformation of quercetin(1) by Gliocladium deliquescens NRRL 1086. Along with the aimed product quercetin 3-O-β-D-glycoside(2), three additional metabolites, 2-protocatechuoyl-phlorogucinol carboxylic acid(3), 2,4,6-trihydroxybenzoic acid(4), and protocatechuic acid(5), were also isolated. The time-course experiments revealed that there were two metabolic routes, regio-selectivity glycosylation and quercetin 2,3-dioxygenation, co-existing in the culture. Both glycosylation and oxidative cleavage rapidly took place after quercetin feeding; about 98% quercetin were consumed within the initial 8 h and the oxdized product(2-protocatechuoyl-phlorogucinol carboxylic acid) was hydrolyzed into two phenolic compounds(2,4,6-trihydroxybenzoic acid and protocatechuic acid). We also investigated the impact of glucose content and metal ions on the two reactions and found that high concentrations of glucose significantly inhibited the oxidative cleavage and improved the yield of isoquercitrin and that Ca^(2+), Fe^(2+), Mn^(2+), Mg^(2+), and Zn^(2+) inhibited glycosylation. To test the promiscuity of this culture, we selected other four flavonols as substrates; the results demonstrated its high regio-selectivity glycosylation ability towards flavonols at C-3 hydroxyl. In conclusion, our findings indicated that the versatile microbe of G. deliquescens NRRL 1086 maitained abundant enzymes, deserving further research.展开更多
During an investigation of mycoparasitic fungi on sclerotia of Sclerotinia sclerotiorum in China, Gliocladium species was consistently encountered and isolated from natural soils collected over the country. Colonizati...During an investigation of mycoparasitic fungi on sclerotia of Sclerotinia sclerotiorum in China, Gliocladium species was consistently encountered and isolated from natural soils collected over the country. Colonization frequencies on sclerotia of S. sclerotiorum by the fungi ranged from 40% to 100% when the sclerotia were introduced into soils and coincubated at 22-24 ℃ for 4 weeks. Identification showed that G. roseum, G. virens and G. catenulatum were the dominant species among the 300 isolates gained. Molecular taxonomy of some Gliocladium isolates analysed by rDNA ITS sequence used ITS1 and ITS4 as primers was demonstrated to be identical with morphological classification. Reinoculation tests by placing surface-sterilized sclerotia onto colony of Gliocladium isolates for 7 days and then surface-sterilized again resulted in 100% sclerotia colonized. Dipping sclerotia with spores suspension of isolates for 5 min and incubated the sclerotia in Petri dishes at 25 ℃ for 24 h resulted in infection of the sclerotia. Microscopic observations indicated that Gliocladium isolates grew along the host hyphae, coiled around, formed appressorium-like structures, penetrated and degraded hyphae of S. sclerotiorum when dual-cultured in slides. Paraffin-section showed that sclerotial tissue collapsed when infected by Gliocladium isolates. Host range test demonstrated that the isolates suppressed hyphal growth of several plant pathogenic fungi, including S. sclerotiorum, Botrytis cinerea, Fusarium oxysporum, Alternaria tenuis, and Rhizoctonia solani. Activities of fungal cell wall degrading enzymes in cultural filtrates and parasitized sclerotia were detected. Results indicated that chitinase and glucanase were important factors involved in the mycoparasitism. A 51 kDa chitinase was isolated and purified from G. catenulatum HL-1-1 culture filtrate. A part of amino acid sequences of the enzyme has been analysed. It was found to have a high homogeneity to chitinase A from Stenotrophomonas maltophilia, while no homogeneity to 展开更多
基金The authors gratefully acknowledge support for this work from the National Natural Science Foundation of China （No. 30570059 and No. 20562015）Yunnan Provincial Natural Science Foundation （No. 2005C0005Q and No. 2005NG03）.
文摘Glioclatine, a novel epidithiodioxopiperazine was isolated from wheat solid-substrate fermentation of Gliocladium roseum YMF1.00133. Its structure was elucidated by HRESI-MS and NMR spectra.
文摘Three compounds were obtained from the mycelia of an endophytic fungus Gliocladium sp. (designated as strain F) of Taxus chinensis (Pilg.) Rehd. growing in Fujian Province, China. Their structures were determined on the basis of spectral analysis. (20S,22S)-4a-homo-22-hydroxy-4-oxaergosta-7,24(28)-dien-3-one was a novel compound. 4,8,12,16-tetramethyl-1,5,9,13-tetraoxacyclohexadecane-2,6,10,14-tetraone was firstly isolated from the genus ofGliocladium and 6,9-epoxyergosta-7,22-dien-3-ol was firstly obtained from the strain F.
基金supported by the National Nature Science Foundation of China(No.21302052)"Program for New Century Excellent Talents in University"awarded to Prof.Jian Zhang"111 Project"from the Ministry of Education of China+1 种基金Fundamental Research Funds for the Central Universities(No.JKZ2011017)Scientific and Innovation Research of College Graduates in Jangsu Province(No.CXLX11_0788)
文摘The present study was designed to explore the substrate scope and biocatalytic capability of Gliocladium deliquescens NRRL 1086 on phenolic natural products. Emodin was subjected to the fermentation culture of Gliocladium deliquescens NRRL 1086 according to the standard two-stage protocol. The biotransformation process was monitored by HPLC-DAD-MS, the main product was isolated by column chromatography, and the structure was elucidated on the basis of NMR spectroscopy. Emodin could be fully metabolized by Gliocladium deliquescens NRRL 1086, resulting in high yield of emodin 6-O-β-D-glucopyranoside and small amount of sulfated product. In conclusion, our results may provide a convenient method to prepare emodin 6-O-β-D-glucopyranoside and the microbe catalyzed glucosylation/sulfation will give an inspiration to pharmacokinetic model studies in vitro.
基金The National Nature Science Foundation of China(NSFC No.20602040)The scientific and innovation research of college graduate in Jiangsu province(CXLX11_0788)
基金supported by the National Natural Science Foundation of China(No.21302052)
文摘With an attempt to synthesize high-value isoquercitrin(quercetin-3-O-β-D-glucopyranoside), we carried out the biotransformation of quercetin(1) by Gliocladium deliquescens NRRL 1086. Along with the aimed product quercetin 3-O-β-D-glycoside(2), three additional metabolites, 2-protocatechuoyl-phlorogucinol carboxylic acid(3), 2,4,6-trihydroxybenzoic acid(4), and protocatechuic acid(5), were also isolated. The time-course experiments revealed that there were two metabolic routes, regio-selectivity glycosylation and quercetin 2,3-dioxygenation, co-existing in the culture. Both glycosylation and oxidative cleavage rapidly took place after quercetin feeding; about 98% quercetin were consumed within the initial 8 h and the oxdized product(2-protocatechuoyl-phlorogucinol carboxylic acid) was hydrolyzed into two phenolic compounds(2,4,6-trihydroxybenzoic acid and protocatechuic acid). We also investigated the impact of glucose content and metal ions on the two reactions and found that high concentrations of glucose significantly inhibited the oxidative cleavage and improved the yield of isoquercitrin and that Ca^(2+), Fe^(2+), Mn^(2+), Mg^(2+), and Zn^(2+) inhibited glycosylation. To test the promiscuity of this culture, we selected other four flavonols as substrates; the results demonstrated its high regio-selectivity glycosylation ability towards flavonols at C-3 hydroxyl. In conclusion, our findings indicated that the versatile microbe of G. deliquescens NRRL 1086 maitained abundant enzymes, deserving further research.
文摘During an investigation of mycoparasitic fungi on sclerotia of Sclerotinia sclerotiorum in China, Gliocladium species was consistently encountered and isolated from natural soils collected over the country. Colonization frequencies on sclerotia of S. sclerotiorum by the fungi ranged from 40% to 100% when the sclerotia were introduced into soils and coincubated at 22-24 ℃ for 4 weeks. Identification showed that G. roseum, G. virens and G. catenulatum were the dominant species among the 300 isolates gained. Molecular taxonomy of some Gliocladium isolates analysed by rDNA ITS sequence used ITS1 and ITS4 as primers was demonstrated to be identical with morphological classification. Reinoculation tests by placing surface-sterilized sclerotia onto colony of Gliocladium isolates for 7 days and then surface-sterilized again resulted in 100% sclerotia colonized. Dipping sclerotia with spores suspension of isolates for 5 min and incubated the sclerotia in Petri dishes at 25 ℃ for 24 h resulted in infection of the sclerotia. Microscopic observations indicated that Gliocladium isolates grew along the host hyphae, coiled around, formed appressorium-like structures, penetrated and degraded hyphae of S. sclerotiorum when dual-cultured in slides. Paraffin-section showed that sclerotial tissue collapsed when infected by Gliocladium isolates. Host range test demonstrated that the isolates suppressed hyphal growth of several plant pathogenic fungi, including S. sclerotiorum, Botrytis cinerea, Fusarium oxysporum, Alternaria tenuis, and Rhizoctonia solani. Activities of fungal cell wall degrading enzymes in cultural filtrates and parasitized sclerotia were detected. Results indicated that chitinase and glucanase were important factors involved in the mycoparasitism. A 51 kDa chitinase was isolated and purified from G. catenulatum HL-1-1 culture filtrate. A part of amino acid sequences of the enzyme has been analysed. It was found to have a high homogeneity to chitinase A from Stenotrophomonas maltophilia, while no homogeneity to
