Three known compounds were isolated from the endophytic fungus Trichoderma sp Xy24 from a mangrove plant Xylocarpus granatum by using various column chromatography techniques. Their structures were identified as harzi...Three known compounds were isolated from the endophytic fungus Trichoderma sp Xy24 from a mangrove plant Xylocarpus granatum by using various column chromatography techniques. Their structures were identified as harzianone （1）, trichoacorenol （2）, and trichodimerol （3） by extensive spectroscopic analysis. Among them, 1 was a harziane diterpene, 2 was a sesquiterpene alcohol, and 3 was a polyketide with a completely symmetric configuration. Compound 3 exhibited medium inhibitory activity with an IC50 value of 74.6 μM using a NA （H7N9）/MUNANA model.展开更多
[Objective] The paper was to study the best fermentation conditions of Trichoderma aureoviride sp. for the production of chitinase, thus provide new enzyme source for chitinsse industry. [Method] Using orthognnal expe...[Objective] The paper was to study the best fermentation conditions of Trichoderma aureoviride sp. for the production of chitinase, thus provide new enzyme source for chitinsse industry. [Method] Using orthognnal experimental design, with the variation of sugar content after enzymatic hydrolysis measured by DNS method as the indicator, the fermentation conditions were optimized. [Result] Taking colloidal chitin as the carbon source and 2% peptone as the nitrogen source with the shaking speed of 170 r/rain, the optimum fermentation conditions of T. aureoviride for the production of chitinase were as follows ： initial pH value of medium, 5.0; inoculation amount, 8% ; bottle volume, 20 ml; 6 d cultivation at 28℃. [Conclusion] The optimum conditions for the production of chitinase were confirmed, which provided basis for the utilization of T. aureoviride.展开更多
In our previous studies, we identified 3 Trichoderma strains with anti-Fusarium oxysporum activity, including T. asperellum 525, T. harzianum 610, and T. pseudokoningii 886. Here, we evaluated the effects of these 3 T...In our previous studies, we identified 3 Trichoderma strains with anti-Fusarium oxysporum activity, including T. asperellum 525, T. harzianum 610, and T. pseudokoningii 886. Here, we evaluated the effects of these 3 Trichoderma strains on preventing cucumber fusarium wilt through pot culture and greenhouse culture experiments. All 3 Trichoderma strains demonstrated higher control effects toward cucumber fusarium wilt than previous studies, with efficacies over 78%. Additionally, inoculation with the 3 Trichoderma strains significantly promoted the quality and yield of cucumbers. Among the 3 strains, Trichoderma 866 was the most effective, with disease control efficacy of 78.64% and a cucumber yield increase of 33%. Furthermore, seedlings inoculated with Trichoderma exhibited significantly increased measures of plant height, stem diameter, leaf area, aboveground fresh weight, underground fresh weight, chlorophyll content, and nitric nitrogen content, as well as the activities of several stress-resistance enzymes, including superoxide dismutase(SOD), peroxidase(POD), catalase(CAT), polyphenol oxidase(PPO), and ascorbate oxidase(AAO). In addition, the plants inoculated with Trichoderma showed decreased cell membrane permeability and malondialdehyde(MDA) content in the leaves. Together, our results suggest that T. asperellum 525, T. harzianum 610, and T. pseudokoningii 886 inoculations inhibit F. oxysporum infection, stimulate the metabolism in cucumbers, and enhance the activities of stress-resistance enzymes, which consequently promote the growth of cucumber plants, prevent cucumber fusarium wilt, and improve the yield and quality of cucumbers. T. harzianum is a commonly used biocontrol fungus, while few studies have focused on T. asperellum or T. koningense. In this study, strains of T. asperellum and T. pseudokoningii showed excellent plant disease prevention and growth promoting effects on cucumber, indicating that they also have great potential as biocontrol fungi.展开更多
Two uridine auxotrophic mutants of Trichoderma reesei were isolated by resistance to 5-fluoroorotic acid after UV mutagenesis. One mutant, called M23, was complemented with the Aspergillus niger pyrG gene carried by p...Two uridine auxotrophic mutants of Trichoderma reesei were isolated by resistance to 5-fluoroorotic acid after UV mutagenesis. One mutant, called M23, was complemented with the Aspergillus niger pyrG gene carried by plasmid pAB4-1. A mutated pyrG gene of M23 was cloned and DNA sequencing analysis indicated that a cytosine was inserted into the 934―939 oligo dC position of the pyrG coding region, resulted in a frameshift mutation. Transformation efficiency was approximately 200―300 transformants per microgram of DNA with plasmid pAB4-1. Stable transformants were obtained by monosporic culture and showed to be prototroph after successive propagation. Vitreoscilla hemoglobin expression plasmid pUCVHb was cotransformed with plasmid pAB4-1 and attained a transformation efficiency of 71.8% or of 26.1% with pAN7-1. Southern blot analysis of the transformants demonstrated that plasmid pUCVHb was integrated into the chromosomal DNA. The experimental results demonstrated that the pyrG-based system was more efficient and timesaving than the conventional hygromycin B resistance-based transformation system.展开更多
The biodegradation characteristic and potential metabolic pathway for removal of environmental N,N-dimethylacetamide （DMAC） by Rhodococcus sp. strain B83 was studied. Rhodococcus sp. strain B83 was isolated from the...The biodegradation characteristic and potential metabolic pathway for removal of environmental N,N-dimethylacetamide （DMAC） by Rhodococcus sp. strain B83 was studied. Rhodococcus sp. strain B83 was isolated from the rhizosphere of a pagoda tree and proved capable of utilizing DMAC as sole source of carbon and nitrogen. Batch culture studies showed that strain B83 could tolerate up to 25 g/L DMAC and showed distinct growth on possible catabolic intermediates except for acetate. The nitrogen balance analysis revealed that approximately 71% of the initial nitrogen was converted to organic nitrogen. DMAC degradation has led to accumulation of acetate and organic nitrogen, meanwhile traces of nitrate and ammonia was build-up but without nitrite. The growth of strain B83 could be inhibited by adding exogenous acetate. By means of the assay of enzymatic degradation of DMAC, several catabolic intermediates at different intervals were observed and identified. Based on the results obtained from culture solution and enzymatic degradation assay, a detailed pathway is proposed for DMAC biodegradation.展开更多
Two new harziane diterpenoids, named（9R,10R）-dihydro-harzianone（1） and harzianelactone（2）, were isolated from the endophytic fungus Trichoderma sp. Xy24 by using various column chromatography techniques. Their s...Two new harziane diterpenoids, named（9R,10R）-dihydro-harzianone（1） and harzianelactone（2）, were isolated from the endophytic fungus Trichoderma sp. Xy24 by using various column chromatography techniques. Their structures were determined on the basis of extensive spectroscopic（HR-ESI-MS, 1D NMR, 2D NMR and CD） analyses. Among them, 1 was the reductive product of harzianone and 2 was the Baeyer–Villiger monooxygenase catalyzed oxidation product of harzianone. Compound 1 exhibited cytotoxic activity against He La and MCF-7 cell lines with IC（50） values of 30.1 μmol/L and 30.7 μmol/L,respectively.展开更多
Isolation of new bacterial strains and recognition of their metabolic activities are highly desirable for sustainability of natural ecosystems.Biodegradation of dimethyl phthalate(DMP)under anoxic conditions has been ...Isolation of new bacterial strains and recognition of their metabolic activities are highly desirable for sustainability of natural ecosystems.Biodegradation of dimethyl phthalate(DMP)under anoxic conditions has been shown to occur as a series of sequential steps using strain CW-1 isolated from digested sludge of Sibao Wastewater Treatment Plant in Hangzhou,China.The microbial colony on LB medium was yellowish,3-5 mm in diameter,convex in the center,and embedded in mucous externally.The individual cells of strain CW-1 are irregular rods,measuring(0.6-0.7)×(0.9-1.0)pm,V-shaped,with clubbed ends,Gram positive and without any filaments.16S rDNA(1438 bp)sequence analysis showed that the strain was related to Arthrobacter sp.CW-1 and can degrade PAEs utilizing nitrate as electron acceptor,but cannot mineralize DMP completely.The degradation pathway was recommended as:dimethyl phthalate(DMP)→monomethyl phthalate(MMP)--,phthalic acid(PA).DMP biodegradation was a first order reaction with degradation rate constant of 0.3033 d 1 and half-life 2.25 d.The DMP conversion to PA by CW-1 could be described by using sequential kinetic model.展开更多
Objective:To investigate the antioxidant activity of soil-borne aetinobacteria.Methods:The total phenolic contents,the level of antioxidant potential by DPPH radical scavenging activity,MO scavenging activity,and ABTS...Objective:To investigate the antioxidant activity of soil-borne aetinobacteria.Methods:The total phenolic contents,the level of antioxidant potential by DPPH radical scavenging activity,MO scavenging activity,and ABTS radical scavenging activity in ethyl acelale extract were determined.Results:The 16 S rDNA sequencing analysis revealed that Streptomyces sp.strain MJM 10778.which was isolated from Hambak Mountain.Korea,has 99.9% similarity to Streptomyces misionensis(S.misionenis) NBRC 13063.The physiological and the morphological test revealed that the strain MJM 10778 has different characteristics from the strain NBRC.13063.The entire antioxidant assay with the ethyl acelale extract displayed good radical scavenging activity.The IC_(50) values of the strain MJM 10778 extract on DPPH,.NO.and ABTS radicals were identified to he 92.8 μg/mL,0.02 μg/ml,and 134.9 μg/mL,respectively.The ethyl acetate extract of the strain MJM 10778 showed an 81.500% of cell viability at 100 μg/mL in Raw264.7cell viability assay.Conclusions:The results obtained suggesl that the ethyl acetate extract of Streptomyces sp.strain MJM 10778 could be considered as a potential source of drug for the diseases that is caused by free radicals with its anti-oxidant activities and low cytotoxicity.展开更多
From the fungus Trichoderma sp.,we isolated seven novel 18-residue peptaibols,neoatroviridins E-K(1−7),and six new 14-residue peptaibols,harzianins NPDG J-O(8−13).Additionally,four previously characterized 18-residue ...From the fungus Trichoderma sp.,we isolated seven novel 18-residue peptaibols,neoatroviridins E-K(1−7),and six new 14-residue peptaibols,harzianins NPDG J-O(8−13).Additionally,four previously characterized 18-residue peptaibols neoatroviridins A-D(14−17)were also identified.The structural configurations of the newly identified peptaibols(1−13)were determined by comprehensive nuclear magnetic resonance(NMR)and high-resolution electrospray ionization tandem mass spectrometry(HR-ESI-MS/MS)data.Their absolute configurations were further determined using Marfey’s method.Notably,compounds 12 and 13 represent the first 14-residue peptaibols containing an acidic amino acid residue.In antimicrobial assessments,all 18-residue peptaibols(1−7,14−17)exhibited moderate inhibitory activities against Staphylococcus aureus 209P,with minimum inhibitory concentration(MIC)values ranging from 8−32μg·mL^(−1).Moreover,compound 9 exhibited moderate inhibitory effect on Candida albicans FIM709,with a MIC value of 16μg·mL^(−1).展开更多
基金Science&Technology Project of Guangdong Province(Grant No.2011A080403020)the Fundamental Research Funds for the Central Universities(Grant No.2012N06)
文摘Three known compounds were isolated from the endophytic fungus Trichoderma sp Xy24 from a mangrove plant Xylocarpus granatum by using various column chromatography techniques. Their structures were identified as harzianone （1）, trichoacorenol （2）, and trichodimerol （3） by extensive spectroscopic analysis. Among them, 1 was a harziane diterpene, 2 was a sesquiterpene alcohol, and 3 was a polyketide with a completely symmetric configuration. Compound 3 exhibited medium inhibitory activity with an IC50 value of 74.6 μM using a NA （H7N9）/MUNANA model.
基金Supported by Science Research Foundation of Henan University(2008YBGG043)~~
文摘[Objective] The paper was to study the best fermentation conditions of Trichoderma aureoviride sp. for the production of chitinase, thus provide new enzyme source for chitinsse industry. [Method] Using orthognnal experimental design, with the variation of sugar content after enzymatic hydrolysis measured by DNS method as the indicator, the fermentation conditions were optimized. [Result] Taking colloidal chitin as the carbon source and 2% peptone as the nitrogen source with the shaking speed of 170 r/rain, the optimum fermentation conditions of T. aureoviride for the production of chitinase were as follows ： initial pH value of medium, 5.0; inoculation amount, 8% ; bottle volume, 20 ml; 6 d cultivation at 28℃. [Conclusion] The optimum conditions for the production of chitinase were confirmed, which provided basis for the utilization of T. aureoviride.
基金support from the National Key R&D Program of China (2018YFD0201202)the National Science and Technology Basic Work, China (2014FY120900)the 948 Program of China (2011-G4)
文摘In our previous studies, we identified 3 Trichoderma strains with anti-Fusarium oxysporum activity, including T. asperellum 525, T. harzianum 610, and T. pseudokoningii 886. Here, we evaluated the effects of these 3 Trichoderma strains on preventing cucumber fusarium wilt through pot culture and greenhouse culture experiments. All 3 Trichoderma strains demonstrated higher control effects toward cucumber fusarium wilt than previous studies, with efficacies over 78%. Additionally, inoculation with the 3 Trichoderma strains significantly promoted the quality and yield of cucumbers. Among the 3 strains, Trichoderma 866 was the most effective, with disease control efficacy of 78.64% and a cucumber yield increase of 33%. Furthermore, seedlings inoculated with Trichoderma exhibited significantly increased measures of plant height, stem diameter, leaf area, aboveground fresh weight, underground fresh weight, chlorophyll content, and nitric nitrogen content, as well as the activities of several stress-resistance enzymes, including superoxide dismutase(SOD), peroxidase(POD), catalase(CAT), polyphenol oxidase(PPO), and ascorbate oxidase(AAO). In addition, the plants inoculated with Trichoderma showed decreased cell membrane permeability and malondialdehyde(MDA) content in the leaves. Together, our results suggest that T. asperellum 525, T. harzianum 610, and T. pseudokoningii 886 inoculations inhibit F. oxysporum infection, stimulate the metabolism in cucumbers, and enhance the activities of stress-resistance enzymes, which consequently promote the growth of cucumber plants, prevent cucumber fusarium wilt, and improve the yield and quality of cucumbers. T. harzianum is a commonly used biocontrol fungus, while few studies have focused on T. asperellum or T. koningense. In this study, strains of T. asperellum and T. pseudokoningii showed excellent plant disease prevention and growth promoting effects on cucumber, indicating that they also have great potential as biocontrol fungi.
基金the National Natural Science Foundation of China(No.30470052)the National Basic Research Program of China(Nos.2003CB716006 and 2004CB719702)the Natural Science Research Foundation for the Doctoral Program of Edu-cation Ministry of China(No.20040422042).
文摘Two uridine auxotrophic mutants of Trichoderma reesei were isolated by resistance to 5-fluoroorotic acid after UV mutagenesis. One mutant, called M23, was complemented with the Aspergillus niger pyrG gene carried by plasmid pAB4-1. A mutated pyrG gene of M23 was cloned and DNA sequencing analysis indicated that a cytosine was inserted into the 934―939 oligo dC position of the pyrG coding region, resulted in a frameshift mutation. Transformation efficiency was approximately 200―300 transformants per microgram of DNA with plasmid pAB4-1. Stable transformants were obtained by monosporic culture and showed to be prototroph after successive propagation. Vitreoscilla hemoglobin expression plasmid pUCVHb was cotransformed with plasmid pAB4-1 and attained a transformation efficiency of 71.8% or of 26.1% with pAN7-1. Southern blot analysis of the transformants demonstrated that plasmid pUCVHb was integrated into the chromosomal DNA. The experimental results demonstrated that the pyrG-based system was more efficient and timesaving than the conventional hygromycin B resistance-based transformation system.
基金supported by the National Natural Science Foundation of China(No.51308440)the Natural Science Foundation of Shaanxi Province(No.2014JM7260)Shaanxi Provincial Department of Education Fund(No.15JK1439)are gratefully acknowledged
文摘The biodegradation characteristic and potential metabolic pathway for removal of environmental N,N-dimethylacetamide （DMAC） by Rhodococcus sp. strain B83 was studied. Rhodococcus sp. strain B83 was isolated from the rhizosphere of a pagoda tree and proved capable of utilizing DMAC as sole source of carbon and nitrogen. Batch culture studies showed that strain B83 could tolerate up to 25 g/L DMAC and showed distinct growth on possible catabolic intermediates except for acetate. The nitrogen balance analysis revealed that approximately 71% of the initial nitrogen was converted to organic nitrogen. DMAC degradation has led to accumulation of acetate and organic nitrogen, meanwhile traces of nitrate and ammonia was build-up but without nitrite. The growth of strain B83 could be inhibited by adding exogenous acetate. By means of the assay of enzymatic degradation of DMAC, several catabolic intermediates at different intervals were observed and identified. Based on the results obtained from culture solution and enzymatic degradation assay, a detailed pathway is proposed for DMAC biodegradation.
基金supported by the Science & Technology Project of Guangdong Province (No. 2011A080403020)
文摘Two new harziane diterpenoids, named（9R,10R）-dihydro-harzianone（1） and harzianelactone（2）, were isolated from the endophytic fungus Trichoderma sp. Xy24 by using various column chromatography techniques. Their structures were determined on the basis of extensive spectroscopic（HR-ESI-MS, 1D NMR, 2D NMR and CD） analyses. Among them, 1 was the reductive product of harzianone and 2 was the Baeyer–Villiger monooxygenase catalyzed oxidation product of harzianone. Compound 1 exhibited cytotoxic activity against He La and MCF-7 cell lines with IC（50） values of 30.1 μmol/L and 30.7 μmol/L,respectively.
文摘Isolation of new bacterial strains and recognition of their metabolic activities are highly desirable for sustainability of natural ecosystems.Biodegradation of dimethyl phthalate(DMP)under anoxic conditions has been shown to occur as a series of sequential steps using strain CW-1 isolated from digested sludge of Sibao Wastewater Treatment Plant in Hangzhou,China.The microbial colony on LB medium was yellowish,3-5 mm in diameter,convex in the center,and embedded in mucous externally.The individual cells of strain CW-1 are irregular rods,measuring(0.6-0.7)×(0.9-1.0)pm,V-shaped,with clubbed ends,Gram positive and without any filaments.16S rDNA(1438 bp)sequence analysis showed that the strain was related to Arthrobacter sp.CW-1 and can degrade PAEs utilizing nitrate as electron acceptor,but cannot mineralize DMP completely.The degradation pathway was recommended as:dimethyl phthalate(DMP)→monomethyl phthalate(MMP)--,phthalic acid(PA).DMP biodegradation was a first order reaction with degradation rate constant of 0.3033 d 1 and half-life 2.25 d.The DMP conversion to PA by CW-1 could be described by using sequential kinetic model.
基金supported by a grant from next-generation BioGreen 21 pmjcet(No.PJ009643).RDA Korea
文摘Objective:To investigate the antioxidant activity of soil-borne aetinobacteria.Methods:The total phenolic contents,the level of antioxidant potential by DPPH radical scavenging activity,MO scavenging activity,and ABTS radical scavenging activity in ethyl acelale extract were determined.Results:The 16 S rDNA sequencing analysis revealed that Streptomyces sp.strain MJM 10778.which was isolated from Hambak Mountain.Korea,has 99.9% similarity to Streptomyces misionensis(S.misionenis) NBRC 13063.The physiological and the morphological test revealed that the strain MJM 10778 has different characteristics from the strain NBRC.13063.The entire antioxidant assay with the ethyl acelale extract displayed good radical scavenging activity.The IC_(50) values of the strain MJM 10778 extract on DPPH,.NO.and ABTS radicals were identified to he 92.8 μg/mL,0.02 μg/ml,and 134.9 μg/mL,respectively.The ethyl acetate extract of the strain MJM 10778 showed an 81.500% of cell viability at 100 μg/mL in Raw264.7cell viability assay.Conclusions:The results obtained suggesl that the ethyl acetate extract of Streptomyces sp.strain MJM 10778 could be considered as a potential source of drug for the diseases that is caused by free radicals with its anti-oxidant activities and low cytotoxicity.
基金supported by the National Key Research and Development Program of China(No.2018YFA0903200//2018YFA0903201)the National Natural Science Foundation of China(Nos.81925037 and 81973213)+6 种基金National High-level Personnel of Special Support Program(No.2017RA2259)the 111 Project of Ministry of Education of the People's Republic of China(No.B13038)Local Innovative and Research Teams Project of Guangdong Pearl River Talents Program(No.2017BT01Y036)Guangdong International Science and Technology Cooperation Base(No.2021A0505020015)Innovative and Research Teams Project of Guangdong Higher Education Institution(No.2021KCXTD001)K.C.Wong Education Foundation(No.Guo-Dong Chen,2021,China)the Science and Technology Planning Project of Guangzhou(No.202201020048)。
文摘From the fungus Trichoderma sp.,we isolated seven novel 18-residue peptaibols,neoatroviridins E-K(1−7),and six new 14-residue peptaibols,harzianins NPDG J-O(8−13).Additionally,four previously characterized 18-residue peptaibols neoatroviridins A-D(14−17)were also identified.The structural configurations of the newly identified peptaibols(1−13)were determined by comprehensive nuclear magnetic resonance(NMR)and high-resolution electrospray ionization tandem mass spectrometry(HR-ESI-MS/MS)data.Their absolute configurations were further determined using Marfey’s method.Notably,compounds 12 and 13 represent the first 14-residue peptaibols containing an acidic amino acid residue.In antimicrobial assessments,all 18-residue peptaibols(1−7,14−17)exhibited moderate inhibitory activities against Staphylococcus aureus 209P,with minimum inhibitory concentration(MIC)values ranging from 8−32μg·mL^(−1).Moreover,compound 9 exhibited moderate inhibitory effect on Candida albicans FIM709,with a MIC value of 16μg·mL^(−1).
