To study the antifungal effect of chalcone derivatives. Methods Sixteenchalcone derivatives were synthesized and confirmed by ~1H NMR and IR spectra, and tested forantifungal activity against four common pathogenic fu...To study the antifungal effect of chalcone derivatives. Methods Sixteenchalcone derivatives were synthesized and confirmed by ~1H NMR and IR spectra, and tested forantifungal activity against four common pathogenic fungi. Their structure-activity relationship isdiscussed. Results Among 16 title compounds, there were 5 new compounds, which have not beenreported before. The preliminary antifungal test showed that all title compounds exhibitedantifungal activities to a certain extent. The activity of compound 8 against Trichophyton rubrumhad a potency equal to that of fluconazole, with a MIC of 4 μg·mL^(-1) . Conclusion Sixteenchalcones were prepared and their antifungal activities against four common pathogenic fungi invitro were examined. Some of them exhibited antifungal activities to a certain extent.展开更多
[Objective] This study aimed to isolate and screen black-spot-resistant en- dophytic fungi strains. [Method] Various species of healthy Rosa chinensis were col- lected from Xi'an, Xianyang, Baoji and Weinan City in S...[Objective] This study aimed to isolate and screen black-spot-resistant en- dophytic fungi strains. [Method] Various species of healthy Rosa chinensis were col- lected from Xi'an, Xianyang, Baoji and Weinan City in Shaanxi Province. Endophytic fungi was isolated from stems and leaves, and purified by 2-3 times of inoculation to screen endophytic fungi antagonistic to Marssonina rosae with modified punching method. [Result] Samples collected from Xianyang exhibited the highest colonization rate and isolation rate; endophytic fungi strains isolated from stems presented the highest colonization rate and isolation rate compared with leaves. A total of 67 en- dophytic fungi strains were isolated from Rosa chinensis, including 3 black spot-re- sistant strains which were all derived from Baoji. [Conclusion] This study laid the foundation for further screening candidate strains of biocontrol fungi and environ- ment-friendly fungal biological control.展开更多
Eleven 1-(1H-1,2,4-triazole)-2-(2,4-diflurophenyl)-3-(N-methyl-N-substituted benzylamino)-2-propanols were designed and synthesized, on the basis of the crystal structure of P450 cytochrome 14α-sterol demethylase(CYP...Eleven 1-(1H-1,2,4-triazole)-2-(2,4-diflurophenyl)-3-(N-methyl-N-substituted benzylamino)-2-propanols were designed and synthesized, on the basis of the crystal structure of P450 cytochrome 14α-sterol demethylase(CYP51) and the docking results of inhibitors to the active site of the enzyme. All title compounds were first by reported. Results of preliminary biological tests showed that most of title compounds exhibited activity against the seven common pathogenic fungi. Compound 11 showed best antifungal activity with broad antifungal spectrum and proved to be more active against Cryptococcus neoformans, Candida albicans, Microsporum lanosum and Trichophyton rubrum than ketoconazole. Compounds 3, 10 and 4 also had high activities.展开更多
Compatible and incompatible reactions in rice plants ( Oryza sativa L. cv. Shenxianggen No.4) were resulted from inoculation with two different virulent races of rice blast fungus ( Magnaporthe grisea (Hebert) B...Compatible and incompatible reactions in rice plants ( Oryza sativa L. cv. Shenxianggen No.4) were resulted from inoculation with two different virulent races of rice blast fungus ( Magnaporthe grisea (Hebert) Barr), and thus an effective infecting system was established between rice plants and the rice blast pathogen. Two cDNA clones that showed induced and temporal patterns in expression in the very early stage in response to infection of the fungus were obtained from the plants by use of differential display. Of the two cDNA clones, Fastresp_a was induced to express in both compatible and incompatible interactions although it was expressed earlier in the former reaction. The second one, Fastresp_b , was only expressed in incompatible interaction. Southern blot analysis of the rice genomic DNA indicated that both of the two clones were from genome of the plant. No significant homology to the two genes was found from the rice gene database. This suggested that they were novel genes in rice and may play important roles in rice resistant response to infection of rice blast fungus.展开更多
The economic losses and the health hazards of the mycotoxins produced by spoilage fungi are the main concerns of the food industry. The spoilage of bakery products by fungi is more common in countries with a high humi...The economic losses and the health hazards of the mycotoxins produced by spoilage fungi are the main concerns of the food industry. The spoilage of bakery products by fungi is more common in countries with a high humidity and temperature. About 5-10% of food production is spoiled by the growth of yeast and fungi in food materials. Similarly, in Western Europe, the growth of the spoilage fungi of bread is estimated to reach more than 200 million Euros per year. The history conditions of the food can be a major factor in determining any fungal spoilage--for example, stored and processed foods are more sensitive to spoilage when compared with fresh and prepared foods. Lactic acid bacteria isolated from Bulgarian wheat and rye flour were used in the present study to check their antifungal properties against pathogenic yeast and fungi imperfecta using standard disc diffusion method in vitro. A broad spectrum of antifungal activity of the six newly identified as L. plantarum strains e Tsl, Ts2, Ts3,Ts4 and Ts5, and L. helveticus Ts6 was estimated. Our in vitro studies were performed with wheat and rye sourdough, in order to simulate a real product and to assess the bio-protective potential of the tested lactobacilli. The used test-cultures are representatives of carcinogenic, toxigenic, deteriorative and allergenic fungi from the genera .4spergillus and Penicillium. The all tested strains completely suppress the growth of against C. glabrata 72. Strains L. plantarum Tsl and Ts3 completely suppress the growth against S. cerevisae. While, in the sample with L. plantarum strains e Tsl, Ts2, Ts3,Ts4 and Ts5, and L. helveticus Ts6, a retarded and weak growth of A. niger and P. claviforme was observed. However, the spore germination and the colony growth started only on the fifth day of the mould lactobacilli co-cultivation, which also should be considered as a good result. In this study six isolates Tsl,Ts2, Ts3, Ts4, Ts5 and Ts6, from the traditional Bulgarian wheat and rye flour have been identified as L. plantarum and L. helveticus and characterized as cultures with promising antifungal activity. Obtained results from the combined molecular identification (16S rRNA gene sequencing) approach contribute to give new data on the microbial biodiversity of this not well-studied niche. The antifungal activity of our new isolates, identified as L. plantarum and L. helveticus, seems to be a promising advantage of these six strains, suggesting their potential applications in different food technologies. However, more experiments have to be conducted to clarify the nature and the mechanisms of the reported antifungal activity and they are still in progress. The combination of dairy origin and strong inhibitory activity of the lactobacillus strains is a prerequisite for their possible application as starters and/or bioprotective antifungal adjuncts.展开更多
In phylum Echinodermata, the family Holothuridae is distinguished by its capacity of bioactive compounds. Sea cu- cumber Holothuria atra is commonly known as the lollyfish. The antifimgal activity was detected using a...In phylum Echinodermata, the family Holothuridae is distinguished by its capacity of bioactive compounds. Sea cu- cumber Holothuria atra is commonly known as the lollyfish. The antifimgal activity was detected using agar well diffusion method against the various fungal strains such as Trichoderma viride, Aspergillus niger, Aspergillus flavis, Candida albicans and Penicillium chrysogenum. Relatively high antifungal activity was seen against Candida albicans at 100 μL-1 concentration of extracts. Zone of inhibition was measured at 18 mm of diameter. The anti-tumor activities were detected against the Vero and Hep2 cell lines using MTT assay. The cells were treated with H. atra extract at concentrations 0.078-10mg mL-1. The extract showed high proliferative activity against the Hep2 cells. The body wall extracts of sea cucumber (H. atra) showed effective antifungal and antitumor activities All these findings suggest that the extracts could be used for the development of drugs.展开更多
The Bacillus strain BH072 isolated from a honey sample showed strong antifungal activity against phytopathogen. Gene cloning test demonstrated that the strain had a tasA gene encoding an antifungal TasA protein. Altho...The Bacillus strain BH072 isolated from a honey sample showed strong antifungal activity against phytopathogen. Gene cloning test demonstrated that the strain had a tasA gene encoding an antifungal TasA protein. Although the wild strain simultaneously produced various antifungal substances, only the physicochemical property and antifungal activity of TasA protein were unclear due to the difficulty in extraction. In this study, tasA gene encoding the protein from Bacillus sp. BH072 was amplified by using the polymerase chain reaction (PCR) method and cloned into pET 28a (+) vector, and then expressed in host cells Escherichia coli BL21 (DE3). The expressed proteins were collected by centrifugation and ultrasonic treatment, and then purified by using nickel-nitrilotriacetic acid (Ni-NTA) metal affinity column and dialysis methods. The result of sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) test showed that an expected protein band appeared with a size of 31 kDa. The expressed products possessed antifungal activity against the phytopathogenic indicator strain Botrytis cinerea. A genetically engineered strain tasA orE, coli was established in this study which can efficiently express Tas A protein.展开更多
New heteroring-substituted thiophene-2-carbohydrazides incorporating pyrrole, thiophene, and pyridine moieties have been synthesized, characterized, and screened for possible antimicrobial activity. Some of the synthe...New heteroring-substituted thiophene-2-carbohydrazides incorporating pyrrole, thiophene, and pyridine moieties have been synthesized, characterized, and screened for possible antimicrobial activity. Some of the synthesized compounds exhibited promising antibacterial activities, but rather modest antifungal activity.展开更多
[Objective] The aim was to study effect of Chaetomium globosum ND35 on plant growth and preliminary study of its biocontrol efficacy, and provide basis for popularization and application of this strain.[ Method] With ...[Objective] The aim was to study effect of Chaetomium globosum ND35 on plant growth and preliminary study of its biocontrol efficacy, and provide basis for popularization and application of this strain.[ Method] With endophytic fungus C. globosum ND35 as a tested strain, effect of C. globosumND35 on plant growth and its biocontrol on five plant diseases were investigated in the greenhouse and field,[Result]The results showed that ND35 promoted growth of lateral root and diameter of breast height of poplar. ND35 can induce poplar to resist Poplar Valsa Canker caused by Valsa sordida and Poplar Rust caused by Melampsora puplicola. ND35 was also able to induce tomato and bean to resist Botrytis cinera. Biocontrol of Bean Stem Rot Rhizoctonia by ND35 was effective as well. [Conclusion] Induced systemic resistance by endophytic C. globosum ND35 plays an important role in biocontrol of plant diseases.展开更多
Objective: To study the effect of fluconzole derivatives from a side chain containing 4-substituted acyl piperazin-1-yl on antifungal activity. Methods: Fourteen title compounds were synthesized and confirmed by the e...Objective: To study the effect of fluconzole derivatives from a side chain containing 4-substituted acyl piperazin-1-yl on antifungal activity. Methods: Fourteen title compounds were synthesized and confirmed by the elementary analysis, 1HNMR and IR spectra. Five deep fungal strains and 3 shallow fungal strains were chosen as the experimental strains.Minimum inhibitory concentrations(MICs) of all title compounds were determined by the method recommended by the National Committee for Clinical Laboratory Standards (NCCLS) using RPMI 1640 test medium. Results: Among the 14 title compounds, 12 were first reported. The results of preliminary antifungal test showed that all the title compounds exhibited potent antifungal activities to a certain extent. The activity of 4 compounds were more than 4 times as high as that of fluconazole and equal to that of ketoconazole against Candida albicans in vitro(MIC 80 value≤0.125 μg/ml). Conclusion: Introduction of a side chain containing 4-substituted acyl piperazin-1-yl into the main part of fluconazole has important influence on antifungal activities of title compounds.展开更多
The molecular factors involved in the three-way interaction between plant, pathogenic fungi and antagonistic/biocontrol fungi, such as Trichoderma, are still poorly understood, even if they represent a matter of inter...The molecular factors involved in the three-way interaction between plant, pathogenic fungi and antagonistic/biocontrol fungi, such as Trichoderma, are still poorly understood, even if they represent a matter of interest for improving crop management and developing new strategies for plant diseases control. The aim of this work is to investigate the components involved in this interaction and, for this purpose, a proteomic approach was used. 2-D maps of the protein extracts from the single components in various interactions between plants (potato, bean, tobacco or tomato), pathogens (Botrytis cinerea, Rhizoctonia solani or Pythium ultimum) and biocontrol fungi (Trichoderma atroviride strain P1 or Trichoderma harzianum strain T22) were obtained. The proteome of each partner was collected separately and extracted by acetone precipitation in presence of trichloroacetic acid and a reducing agent (DTT). The extracted proteins were separated by isoelectrofocusing (IEF), using IPG (Immobilized pH gradient) strips, followed by SDS-PAGE. In order to improve resolution the separations were performed both on wide than narrow pH range and on different gel lengths. Differential spots were noted in the proteome of the three-way interaction when compared to each single component. These were further characterized by mass spectrometry and in silico analysis with the aim of identifying and cloning the relative genes. During the in vitro interaction of T. harzianum strain T22 with tomato and the culture filtrate or cell walls of pathogens, the spot number was higher than in the presence of pathogen biomass. In terms of Trichoderma differential proteins displayed on 2D gels, the most important changes were obtained in the presence of P. ultimum . During the in vivo interaction with tomato, the antagonist proteome changed much more in presence of soilborne fungi R. solani and P. ultimum than with the foliar fungus B. cinerea, both in terms of total and increased or novel spots. In silico analysis of some of those spots revealed homology with intracellular enzymes (GTPases, hydrolases) and with stress-related proteins (heat shock proteins HSP70, bacteriocin cloacin). Specific proteins in the plant proteome, i.e. pathogenesis-related proteins, have been identified during the in vivo interaction of bean with R. solani and T. atroviride strain P1. This is in agreement with the demonstrated ability of these beneficial fungi to induce plant systemic disease resistance by activating expression of defence-related genes. Proteins extracted from T. atrovride strain P1 which were analysed by mass spectrometry, revealed some interesting homologies with a fungal hydrophobin of Pleurotus ostreatus and an ABC transporter of Ralstonia metallidurans. These could represent molecular factors involved in the antagonistic mechanisms of Trichoderma and play a role in the three-way interaction with the plant and other microbes.展开更多
To solve the problem of lack of water in arid areas and barren soil in the process of ecological restoration, the growth and drought resistance of Sainfoin (Onobrychis vidifolia Scop.) was studied by inoculation of ...To solve the problem of lack of water in arid areas and barren soil in the process of ecological restoration, the growth and drought resistance of Sainfoin (Onobrychis vidifolia Scop.) was studied by inoculation of AMF (arbuscular rnycorrhizal fungi), under drought stress. The results show that the inoculation of AMF can significantly improve the growth and mycorrhizal infection rate of Sainfoin and accelerate the absorption of water and nutrients by the roots compared with uninoculated plants. On the 40th day under drought stress, the relative water content, total nitrogen and total phosphorus content of the leaves of inoculated plants increased by 7.27%, 4.21% and 2.40%, respectively, the osmotic adjustment property in plant cells was improved, the protective enzyme system was improved and membrane lipid peroxida- tion was reduced. The inoculation of AMF can slow down the damage from drought, improve the drought resistance of Sainfoin, and will be of great significance to the ecologic restoration in arid areas.展开更多
Chitosan oligomers (average Dp-4) are known for their antifungal activity and wood decay resistance. These oligomers are susceptible to moisture, and promote yeast growth upon air exposure after a sufficient length ...Chitosan oligomers (average Dp-4) are known for their antifungal activity and wood decay resistance. These oligomers are susceptible to moisture, and promote yeast growth upon air exposure after a sufficient length of time. Chitosan oligomers of three different states viz. completely dried, freshly prepared and highly viscous form, were prepared to compare their in-vitro antifungal activities against three brown-rot fungi, two sapstain and one mould fungus using agar nutrient medium. Additionally, a mixture of chitosan oligomers and boric acid was used for wood treatment. The nutrient medium bioassay results show that all states of chitosan oligomers inhibited the growth of tested basidiomycetes fungi, but not sapstain and mould fungi. Subsequently, wood decay results confirm antifungal activity of chitosan oligomers plus boron against basidiomycetes, but highlighted their leachability upon water exposure.展开更多
This study was undertaken to explore new antifungal compounds from the methanolic extract of G. sinaicus. Two cardenolide compounds were isolated and identified by GC-MS as cardenolide glycoside, 15-hydroxy-3,4,5,6-de...This study was undertaken to explore new antifungal compounds from the methanolic extract of G. sinaicus. Two cardenolide compounds were isolated and identified by GC-MS as cardenolide glycoside, 15-hydroxy-3,4,5,6-dehydrocalotropin and cardenolide genin, 3,4,5,6-dehydrocalotropagenin. The antifungal activity of these compounds was assessed. Results revealed that both compounds showed pronounced fungicidal activity against both soil borne fungi, R. solani, F. oxysporium, and postharvest fungi, R. stolonifer, P. digtatum, compared to the standard fungicides, flutolanil and copper oxychloride, respectively. The ECs0 values of the cardenolide genin were 0.703, 13.63 and 4.22, 8.403 lag/mL forR. solani, F. oxysporium andR. stolonifer, P. digtatum respectively. On the other hand, the ECs0 values of the standard fungicide, flutolanil, were 9.49 and 61.22 ~tg/mL against R. solani and F. oxysporium. While the ECso values of copper oxychloride were 279.94 and 187.13 p.g/mL against R. stolonifer and P. digtatum, respectively. The results showed that cellulase, PME, PPO of the tested fungi was more sensitive than to cardenolide genin. The strong antifungal activity of cardenolide genin reported in this study indicated that has a potential to be used as fungicides.展开更多
The present study was conducted to investigate antifungal activity ofLawsonia inermis (Henna plant). Leaf samples of the plants were collected from Eastern Nile of Khartoum state, Sudan. Ethanol and petroleum ether ...The present study was conducted to investigate antifungal activity ofLawsonia inermis (Henna plant). Leaf samples of the plants were collected from Eastern Nile of Khartoum state, Sudan. Ethanol and petroleum ether extracts in various concentrations were obtained by maceration (cold method). The extracts were bioassay in vitro to know their bioactivity to inhibit the growth of tested fungi. The cup plate agar diffusion method was adopted to assess the antifungal activity of the extracts against tested yeasts while agar incorporated method was used for other molds. Both extracts revealed anti fungal activity against all yeast strains except Pichiafabianii which was found resistant to both ethanol and ether extracts. The results displayed antifungal activity against tested fungi. Minimum mould concentration (MMC) of the extracts was determined. The obtained results revealed antifungal activity of henna leaves extracts which support the traditional use of the Henna in therapy of fungal infections. The possibility of therapeutic use of Sudanese henna as antifungal agents is recommended.展开更多
T4 lysozyme was engineered with disulfide bonds and expressed in Pichia pastoris. The secreted proteins were purified and made into powder by lyophiliza-tion. Recombinant protein purity was more than 70% measured by H...T4 lysozyme was engineered with disulfide bonds and expressed in Pichia pastoris. The secreted proteins were purified and made into powder by lyophiliza-tion. Recombinant protein purity was more than 70% measured by HPLC. The lytic activity of variant T4-lysozyme was measured by the lysis of the cel wal of Xan-thomonas oryzae pv. oryzae, X. oryzae pv. oryzicola, Ralstonia solanacearum comb. nov, Clavibacter michiganensis subsp. michiganensis, X. campestris pv. mal-vacearum, Fusarium oxysporium sp. vasinfectum, Verticil ium dahliae kleb. Inhibition zone assay showed that variant T4 lysozyme significantly inhibited X. o. oryzicola and X. c. malvacearum. The antifungal activities of this protein against F. o. vasin-fectum and V. d. kleb were also analyzed.展开更多
The improvement of propionic acid production for antifungal activity, as fermenting by calcium alginate immobilized cells of Propionibacterium acidipropionici TISTR 442 was investigated by using whey as substrate. Opt...The improvement of propionic acid production for antifungal activity, as fermenting by calcium alginate immobilized cells of Propionibacterium acidipropionici TISTR 442 was investigated by using whey as substrate. Optimal condition for immobilization was performed by adjusting tube distance to CaCI2 solution to be 4-6 cm and 7 mL/min flow rate of alginate gel. The production of propionic acid by immobilized cells in a 2 L fermentor using 1% CaCO3 and 5 N KOH to control the pH at 6.5 gave maximum propionic acid and they had consistent potential to recycle 2 rounds of fermentation and produced the total of 29.24 g/L propionic acid (15.85 ± 0.25 g/L and 13.39 ± 0.25 g/L propionic acid from Batch 1 and Batch 2 fermentation, respectively). Compared to free-cell fermentation, propionic acid productivity increased 20% (0.083 g/h vs. 0.070 g/h) and fermentation time reduced 11% (192 h vs. 216 h) in 2 L fermentor with 40 g/L initial total sugar from whey. The fermented propionic acid as well as the commercial propionic acid from chemical process was able to inhibit the growth of the fungal tested.展开更多
The outbreak of oxidative stress, inflammatory diseases and mycoses, constitute an important public health problem. This could be due to the increase of risk factors, side effects and expensive therapeutic molecules a...The outbreak of oxidative stress, inflammatory diseases and mycoses, constitute an important public health problem. This could be due to the increase of risk factors, side effects and expensive therapeutic molecules available. In the aim to find the potential spring of new therapeutic molecules with efficient and wide spectrum of action, the antiradical, anti-inflammatory and antifungal activities of two essential oils were evaluated. The essential oils were extracted by hydrodistillation. The antiradical activity was evaluated to use DPPH (2,2-diphenyl-l-picrylhydrazyl) scavenging method and the anti-inflammatory activity was determined using the enzymatic method. The disc diffusion and dilution methods were used to evaluate growth inhibition of three yeasts, three moulds and three dermatophytes. The yields of extraction of Apium graveolens and Thymus vulgaris essential oils were 0.14% and 0.32% respectively. These essential oils showed antiradical properties with respective SC50 of 0.41 and 0.06 g/L for Apium graveolens and Thymus vulgaris. Only Thymus vulgaris presented an anti-inflammatory activity with an IC50 of 0.19 g/L. Cryptococcus neoformans was the most susceptible fungal strain while C. albicans was the most resistant one. The results were compared with the standard antifungal. These results show that these essential oils could be exploited as potential spring of molecules endowed with antiradical, anti-inflammatory and antifungal activities.展开更多
文摘To study the antifungal effect of chalcone derivatives. Methods Sixteenchalcone derivatives were synthesized and confirmed by ~1H NMR and IR spectra, and tested forantifungal activity against four common pathogenic fungi. Their structure-activity relationship isdiscussed. Results Among 16 title compounds, there were 5 new compounds, which have not beenreported before. The preliminary antifungal test showed that all title compounds exhibitedantifungal activities to a certain extent. The activity of compound 8 against Trichophyton rubrumhad a potency equal to that of fluconazole, with a MIC of 4 μg·mL^(-1) . Conclusion Sixteenchalcones were prepared and their antifungal activities against four common pathogenic fungi invitro were examined. Some of them exhibited antifungal activities to a certain extent.
基金Supported by National Natural Science Foundation of China(No.31000144)Project of Shaanxi Provincial Science and Technology Department(No.2012JQ3017)+1 种基金Project of Xi'an Science and Technology Bureau[NC1206(3)]Project of Education Department of Shaanxi Provincial Government(No.12JK1106)~~
文摘[Objective] This study aimed to isolate and screen black-spot-resistant en- dophytic fungi strains. [Method] Various species of healthy Rosa chinensis were col- lected from Xi'an, Xianyang, Baoji and Weinan City in Shaanxi Province. Endophytic fungi was isolated from stems and leaves, and purified by 2-3 times of inoculation to screen endophytic fungi antagonistic to Marssonina rosae with modified punching method. [Result] Samples collected from Xianyang exhibited the highest colonization rate and isolation rate; endophytic fungi strains isolated from stems presented the highest colonization rate and isolation rate compared with leaves. A total of 67 en- dophytic fungi strains were isolated from Rosa chinensis, including 3 black spot-re- sistant strains which were all derived from Baoji. [Conclusion] This study laid the foundation for further screening candidate strains of biocontrol fungi and environ- ment-friendly fungal biological control.
文摘Eleven 1-(1H-1,2,4-triazole)-2-(2,4-diflurophenyl)-3-(N-methyl-N-substituted benzylamino)-2-propanols were designed and synthesized, on the basis of the crystal structure of P450 cytochrome 14α-sterol demethylase(CYP51) and the docking results of inhibitors to the active site of the enzyme. All title compounds were first by reported. Results of preliminary biological tests showed that most of title compounds exhibited activity against the seven common pathogenic fungi. Compound 11 showed best antifungal activity with broad antifungal spectrum and proved to be more active against Cryptococcus neoformans, Candida albicans, Microsporum lanosum and Trichophyton rubrum than ketoconazole. Compounds 3, 10 and 4 also had high activities.
文摘Compatible and incompatible reactions in rice plants ( Oryza sativa L. cv. Shenxianggen No.4) were resulted from inoculation with two different virulent races of rice blast fungus ( Magnaporthe grisea (Hebert) Barr), and thus an effective infecting system was established between rice plants and the rice blast pathogen. Two cDNA clones that showed induced and temporal patterns in expression in the very early stage in response to infection of the fungus were obtained from the plants by use of differential display. Of the two cDNA clones, Fastresp_a was induced to express in both compatible and incompatible interactions although it was expressed earlier in the former reaction. The second one, Fastresp_b , was only expressed in incompatible interaction. Southern blot analysis of the rice genomic DNA indicated that both of the two clones were from genome of the plant. No significant homology to the two genes was found from the rice gene database. This suggested that they were novel genes in rice and may play important roles in rice resistant response to infection of rice blast fungus.
文摘The economic losses and the health hazards of the mycotoxins produced by spoilage fungi are the main concerns of the food industry. The spoilage of bakery products by fungi is more common in countries with a high humidity and temperature. About 5-10% of food production is spoiled by the growth of yeast and fungi in food materials. Similarly, in Western Europe, the growth of the spoilage fungi of bread is estimated to reach more than 200 million Euros per year. The history conditions of the food can be a major factor in determining any fungal spoilage--for example, stored and processed foods are more sensitive to spoilage when compared with fresh and prepared foods. Lactic acid bacteria isolated from Bulgarian wheat and rye flour were used in the present study to check their antifungal properties against pathogenic yeast and fungi imperfecta using standard disc diffusion method in vitro. A broad spectrum of antifungal activity of the six newly identified as L. plantarum strains e Tsl, Ts2, Ts3,Ts4 and Ts5, and L. helveticus Ts6 was estimated. Our in vitro studies were performed with wheat and rye sourdough, in order to simulate a real product and to assess the bio-protective potential of the tested lactobacilli. The used test-cultures are representatives of carcinogenic, toxigenic, deteriorative and allergenic fungi from the genera .4spergillus and Penicillium. The all tested strains completely suppress the growth of against C. glabrata 72. Strains L. plantarum Tsl and Ts3 completely suppress the growth against S. cerevisae. While, in the sample with L. plantarum strains e Tsl, Ts2, Ts3,Ts4 and Ts5, and L. helveticus Ts6, a retarded and weak growth of A. niger and P. claviforme was observed. However, the spore germination and the colony growth started only on the fifth day of the mould lactobacilli co-cultivation, which also should be considered as a good result. In this study six isolates Tsl,Ts2, Ts3, Ts4, Ts5 and Ts6, from the traditional Bulgarian wheat and rye flour have been identified as L. plantarum and L. helveticus and characterized as cultures with promising antifungal activity. Obtained results from the combined molecular identification (16S rRNA gene sequencing) approach contribute to give new data on the microbial biodiversity of this not well-studied niche. The antifungal activity of our new isolates, identified as L. plantarum and L. helveticus, seems to be a promising advantage of these six strains, suggesting their potential applications in different food technologies. However, more experiments have to be conducted to clarify the nature and the mechanisms of the reported antifungal activity and they are still in progress. The combination of dairy origin and strong inhibitory activity of the lactobacillus strains is a prerequisite for their possible application as starters and/or bioprotective antifungal adjuncts.
文摘In phylum Echinodermata, the family Holothuridae is distinguished by its capacity of bioactive compounds. Sea cu- cumber Holothuria atra is commonly known as the lollyfish. The antifimgal activity was detected using agar well diffusion method against the various fungal strains such as Trichoderma viride, Aspergillus niger, Aspergillus flavis, Candida albicans and Penicillium chrysogenum. Relatively high antifungal activity was seen against Candida albicans at 100 μL-1 concentration of extracts. Zone of inhibition was measured at 18 mm of diameter. The anti-tumor activities were detected against the Vero and Hep2 cell lines using MTT assay. The cells were treated with H. atra extract at concentrations 0.078-10mg mL-1. The extract showed high proliferative activity against the Hep2 cells. The body wall extracts of sea cucumber (H. atra) showed effective antifungal and antitumor activities All these findings suggest that the extracts could be used for the development of drugs.
文摘The Bacillus strain BH072 isolated from a honey sample showed strong antifungal activity against phytopathogen. Gene cloning test demonstrated that the strain had a tasA gene encoding an antifungal TasA protein. Although the wild strain simultaneously produced various antifungal substances, only the physicochemical property and antifungal activity of TasA protein were unclear due to the difficulty in extraction. In this study, tasA gene encoding the protein from Bacillus sp. BH072 was amplified by using the polymerase chain reaction (PCR) method and cloned into pET 28a (+) vector, and then expressed in host cells Escherichia coli BL21 (DE3). The expressed proteins were collected by centrifugation and ultrasonic treatment, and then purified by using nickel-nitrilotriacetic acid (Ni-NTA) metal affinity column and dialysis methods. The result of sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) test showed that an expected protein band appeared with a size of 31 kDa. The expressed products possessed antifungal activity against the phytopathogenic indicator strain Botrytis cinerea. A genetically engineered strain tasA orE, coli was established in this study which can efficiently express Tas A protein.
文摘New heteroring-substituted thiophene-2-carbohydrazides incorporating pyrrole, thiophene, and pyridine moieties have been synthesized, characterized, and screened for possible antimicrobial activity. Some of the synthesized compounds exhibited promising antibacterial activities, but rather modest antifungal activity.
基金Supported by National Natural Science Foundation of China(30872024,30571498)Students Research Training (SRT) of Shandong Agricultural University (0802024)~~
文摘[Objective] The aim was to study effect of Chaetomium globosum ND35 on plant growth and preliminary study of its biocontrol efficacy, and provide basis for popularization and application of this strain.[ Method] With endophytic fungus C. globosum ND35 as a tested strain, effect of C. globosumND35 on plant growth and its biocontrol on five plant diseases were investigated in the greenhouse and field,[Result]The results showed that ND35 promoted growth of lateral root and diameter of breast height of poplar. ND35 can induce poplar to resist Poplar Valsa Canker caused by Valsa sordida and Poplar Rust caused by Melampsora puplicola. ND35 was also able to induce tomato and bean to resist Botrytis cinera. Biocontrol of Bean Stem Rot Rhizoctonia by ND35 was effective as well. [Conclusion] Induced systemic resistance by endophytic C. globosum ND35 plays an important role in biocontrol of plant diseases.
文摘Objective: To study the effect of fluconzole derivatives from a side chain containing 4-substituted acyl piperazin-1-yl on antifungal activity. Methods: Fourteen title compounds were synthesized and confirmed by the elementary analysis, 1HNMR and IR spectra. Five deep fungal strains and 3 shallow fungal strains were chosen as the experimental strains.Minimum inhibitory concentrations(MICs) of all title compounds were determined by the method recommended by the National Committee for Clinical Laboratory Standards (NCCLS) using RPMI 1640 test medium. Results: Among the 14 title compounds, 12 were first reported. The results of preliminary antifungal test showed that all the title compounds exhibited potent antifungal activities to a certain extent. The activity of 4 compounds were more than 4 times as high as that of fluconazole and equal to that of ketoconazole against Candida albicans in vitro(MIC 80 value≤0.125 μg/ml). Conclusion: Introduction of a side chain containing 4-substituted acyl piperazin-1-yl into the main part of fluconazole has important influence on antifungal activities of title compounds.
文摘The molecular factors involved in the three-way interaction between plant, pathogenic fungi and antagonistic/biocontrol fungi, such as Trichoderma, are still poorly understood, even if they represent a matter of interest for improving crop management and developing new strategies for plant diseases control. The aim of this work is to investigate the components involved in this interaction and, for this purpose, a proteomic approach was used. 2-D maps of the protein extracts from the single components in various interactions between plants (potato, bean, tobacco or tomato), pathogens (Botrytis cinerea, Rhizoctonia solani or Pythium ultimum) and biocontrol fungi (Trichoderma atroviride strain P1 or Trichoderma harzianum strain T22) were obtained. The proteome of each partner was collected separately and extracted by acetone precipitation in presence of trichloroacetic acid and a reducing agent (DTT). The extracted proteins were separated by isoelectrofocusing (IEF), using IPG (Immobilized pH gradient) strips, followed by SDS-PAGE. In order to improve resolution the separations were performed both on wide than narrow pH range and on different gel lengths. Differential spots were noted in the proteome of the three-way interaction when compared to each single component. These were further characterized by mass spectrometry and in silico analysis with the aim of identifying and cloning the relative genes. During the in vitro interaction of T. harzianum strain T22 with tomato and the culture filtrate or cell walls of pathogens, the spot number was higher than in the presence of pathogen biomass. In terms of Trichoderma differential proteins displayed on 2D gels, the most important changes were obtained in the presence of P. ultimum . During the in vivo interaction with tomato, the antagonist proteome changed much more in presence of soilborne fungi R. solani and P. ultimum than with the foliar fungus B. cinerea, both in terms of total and increased or novel spots. In silico analysis of some of those spots revealed homology with intracellular enzymes (GTPases, hydrolases) and with stress-related proteins (heat shock proteins HSP70, bacteriocin cloacin). Specific proteins in the plant proteome, i.e. pathogenesis-related proteins, have been identified during the in vivo interaction of bean with R. solani and T. atroviride strain P1. This is in agreement with the demonstrated ability of these beneficial fungi to induce plant systemic disease resistance by activating expression of defence-related genes. Proteins extracted from T. atrovride strain P1 which were analysed by mass spectrometry, revealed some interesting homologies with a fungal hydrophobin of Pleurotus ostreatus and an ABC transporter of Ralstonia metallidurans. These could represent molecular factors involved in the antagonistic mechanisms of Trichoderma and play a role in the three-way interaction with the plant and other microbes.
基金provided by the Science and Technology Major Project of Shanxi Province (No. 20121101008), is gratefully acknowledged
文摘To solve the problem of lack of water in arid areas and barren soil in the process of ecological restoration, the growth and drought resistance of Sainfoin (Onobrychis vidifolia Scop.) was studied by inoculation of AMF (arbuscular rnycorrhizal fungi), under drought stress. The results show that the inoculation of AMF can significantly improve the growth and mycorrhizal infection rate of Sainfoin and accelerate the absorption of water and nutrients by the roots compared with uninoculated plants. On the 40th day under drought stress, the relative water content, total nitrogen and total phosphorus content of the leaves of inoculated plants increased by 7.27%, 4.21% and 2.40%, respectively, the osmotic adjustment property in plant cells was improved, the protective enzyme system was improved and membrane lipid peroxida- tion was reduced. The inoculation of AMF can slow down the damage from drought, improve the drought resistance of Sainfoin, and will be of great significance to the ecologic restoration in arid areas.
文摘Chitosan oligomers (average Dp-4) are known for their antifungal activity and wood decay resistance. These oligomers are susceptible to moisture, and promote yeast growth upon air exposure after a sufficient length of time. Chitosan oligomers of three different states viz. completely dried, freshly prepared and highly viscous form, were prepared to compare their in-vitro antifungal activities against three brown-rot fungi, two sapstain and one mould fungus using agar nutrient medium. Additionally, a mixture of chitosan oligomers and boric acid was used for wood treatment. The nutrient medium bioassay results show that all states of chitosan oligomers inhibited the growth of tested basidiomycetes fungi, but not sapstain and mould fungi. Subsequently, wood decay results confirm antifungal activity of chitosan oligomers plus boron against basidiomycetes, but highlighted their leachability upon water exposure.
文摘This study was undertaken to explore new antifungal compounds from the methanolic extract of G. sinaicus. Two cardenolide compounds were isolated and identified by GC-MS as cardenolide glycoside, 15-hydroxy-3,4,5,6-dehydrocalotropin and cardenolide genin, 3,4,5,6-dehydrocalotropagenin. The antifungal activity of these compounds was assessed. Results revealed that both compounds showed pronounced fungicidal activity against both soil borne fungi, R. solani, F. oxysporium, and postharvest fungi, R. stolonifer, P. digtatum, compared to the standard fungicides, flutolanil and copper oxychloride, respectively. The ECs0 values of the cardenolide genin were 0.703, 13.63 and 4.22, 8.403 lag/mL forR. solani, F. oxysporium andR. stolonifer, P. digtatum respectively. On the other hand, the ECs0 values of the standard fungicide, flutolanil, were 9.49 and 61.22 ~tg/mL against R. solani and F. oxysporium. While the ECso values of copper oxychloride were 279.94 and 187.13 p.g/mL against R. stolonifer and P. digtatum, respectively. The results showed that cellulase, PME, PPO of the tested fungi was more sensitive than to cardenolide genin. The strong antifungal activity of cardenolide genin reported in this study indicated that has a potential to be used as fungicides.
文摘The present study was conducted to investigate antifungal activity ofLawsonia inermis (Henna plant). Leaf samples of the plants were collected from Eastern Nile of Khartoum state, Sudan. Ethanol and petroleum ether extracts in various concentrations were obtained by maceration (cold method). The extracts were bioassay in vitro to know their bioactivity to inhibit the growth of tested fungi. The cup plate agar diffusion method was adopted to assess the antifungal activity of the extracts against tested yeasts while agar incorporated method was used for other molds. Both extracts revealed anti fungal activity against all yeast strains except Pichiafabianii which was found resistant to both ethanol and ether extracts. The results displayed antifungal activity against tested fungi. Minimum mould concentration (MMC) of the extracts was determined. The obtained results revealed antifungal activity of henna leaves extracts which support the traditional use of the Henna in therapy of fungal infections. The possibility of therapeutic use of Sudanese henna as antifungal agents is recommended.
基金Supported by the National Biotechnology Program for Crop Breeding(2013ZX08005004,2009ZX08009-089B)
文摘T4 lysozyme was engineered with disulfide bonds and expressed in Pichia pastoris. The secreted proteins were purified and made into powder by lyophiliza-tion. Recombinant protein purity was more than 70% measured by HPLC. The lytic activity of variant T4-lysozyme was measured by the lysis of the cel wal of Xan-thomonas oryzae pv. oryzae, X. oryzae pv. oryzicola, Ralstonia solanacearum comb. nov, Clavibacter michiganensis subsp. michiganensis, X. campestris pv. mal-vacearum, Fusarium oxysporium sp. vasinfectum, Verticil ium dahliae kleb. Inhibition zone assay showed that variant T4 lysozyme significantly inhibited X. o. oryzicola and X. c. malvacearum. The antifungal activities of this protein against F. o. vasin-fectum and V. d. kleb were also analyzed.
文摘The improvement of propionic acid production for antifungal activity, as fermenting by calcium alginate immobilized cells of Propionibacterium acidipropionici TISTR 442 was investigated by using whey as substrate. Optimal condition for immobilization was performed by adjusting tube distance to CaCI2 solution to be 4-6 cm and 7 mL/min flow rate of alginate gel. The production of propionic acid by immobilized cells in a 2 L fermentor using 1% CaCO3 and 5 N KOH to control the pH at 6.5 gave maximum propionic acid and they had consistent potential to recycle 2 rounds of fermentation and produced the total of 29.24 g/L propionic acid (15.85 ± 0.25 g/L and 13.39 ± 0.25 g/L propionic acid from Batch 1 and Batch 2 fermentation, respectively). Compared to free-cell fermentation, propionic acid productivity increased 20% (0.083 g/h vs. 0.070 g/h) and fermentation time reduced 11% (192 h vs. 216 h) in 2 L fermentor with 40 g/L initial total sugar from whey. The fermented propionic acid as well as the commercial propionic acid from chemical process was able to inhibit the growth of the fungal tested.
文摘The outbreak of oxidative stress, inflammatory diseases and mycoses, constitute an important public health problem. This could be due to the increase of risk factors, side effects and expensive therapeutic molecules available. In the aim to find the potential spring of new therapeutic molecules with efficient and wide spectrum of action, the antiradical, anti-inflammatory and antifungal activities of two essential oils were evaluated. The essential oils were extracted by hydrodistillation. The antiradical activity was evaluated to use DPPH (2,2-diphenyl-l-picrylhydrazyl) scavenging method and the anti-inflammatory activity was determined using the enzymatic method. The disc diffusion and dilution methods were used to evaluate growth inhibition of three yeasts, three moulds and three dermatophytes. The yields of extraction of Apium graveolens and Thymus vulgaris essential oils were 0.14% and 0.32% respectively. These essential oils showed antiradical properties with respective SC50 of 0.41 and 0.06 g/L for Apium graveolens and Thymus vulgaris. Only Thymus vulgaris presented an anti-inflammatory activity with an IC50 of 0.19 g/L. Cryptococcus neoformans was the most susceptible fungal strain while C. albicans was the most resistant one. The results were compared with the standard antifungal. These results show that these essential oils could be exploited as potential spring of molecules endowed with antiradical, anti-inflammatory and antifungal activities.