Mycelial waste of Streptomyces aureofaciences procured from the aureomycin fermentation industry is used as biosorbent for Au3+. The properties of Au3+ adsorption by the mycelial waste are studied. The results indicat...Mycelial waste of Streptomyces aureofaciences procured from the aureomycin fermentation industry is used as biosorbent for Au3+. The properties of Au3+ adsorption by the mycelial waste are studied. The results indicate that the optimum pH value of Au3+ adsorption is 3.5. The biosorption is a rapid and non-temperature-dependent process. The bio-sorptive capacity with 45.6 mg/g and efficiency with 91.2% are achieved under the conditions of pH 3.5 and 30℃ for 45 min, in which the ratio is 50 mg/g dry weight for the concentrations of initial Au3+ and the mycelial waste. The Au3+ ions adsorbed on the mycelial waste can be eluted. The observation in a transmission electron microscope shows that the Au3+ ions can be reduced to Au particles by the mycelial waste and the Au can become gold crystals with differentforms and sizes. X-ray photoelectron spectroscopy analysis further proves that the Au3+ can be reduced to Au0 by the mycelial waste.展开更多
Pilot scale experiments with forced aeration were conducted to estimate effects of aeration rates on the performance of composting penicillin mycelial dreg using sewage sludge as inoculation. Three aeration rates of 0...Pilot scale experiments with forced aeration were conducted to estimate effects of aeration rates on the performance of composting penicillin mycelial dreg using sewage sludge as inoculation. Three aeration rates of 0.15, 0.50 and 0.90 L/(min·kg) organic matter(OM) were examined. The principal physicochemical parameters were monitored during the 32 day composting period. Results showed that the higher aeration rate of 0.90 L/(min·kg) did not corresponded to a longer thermophilic duration and higher rates of OM degradation;but the lower aeration rate of 0.15 L/(min·kg) did induce an accumulation of NH+4-N contents due to the inhibition of nitrification. On the other hand, aeration rate has little effect on degradation of penicillin. The results show that the longest phase of thermophilic temperatures ≥ 55°C, the maximum NO-3-N content and seed germination, and the minimum C/N ratio were obtained with 0.50 L/(min·kg) OM. Therefore, aeration rates of0.50 L/(min·kg) OM can be recommended for composting penicillin mycelial dreg.展开更多
In order to improve the efficient decolorization of dye-containing water by biosorbent and understand the biosorption mechanism, the self-immobilization mycelial pellets were prepared using a marine-derived fungus Asp...In order to improve the efficient decolorization of dye-containing water by biosorbent and understand the biosorption mechanism, the self-immobilization mycelial pellets were prepared using a marine-derived fungus Aspergillus niger ZJUBE-1, and an azo dye, Congo red was chosen as a model dye to investigate batch decolorization efficiency by pellets. The pellets as biosorbent showed strong salt and acid tolerance in biosorption process. The results for dye adsorption showed that the biosorption process fitted well with models of pseudo-second-order kinetic and Langmuir isotherm, with a maximum adsorption capacity of 263.2 mg·g^(-1) mycelium. During 6 batches of continuous decolorization operation, the mycelial pellets could possess efficient decolorization abilities(>98.5%).The appearance of new peak in the UV–Vis spectral result indicated that the decolorization process may also contain biodegradation. The mechanism studies showed that efficient biosorption ability of pellets only relies on the active zone on the surface of the pellet, which can be enhanced by nutrition supplement or be shifted outward by a reculture process.展开更多
The influence of ten agro-residues,i.e.,wheat straw(WS),poplar wood sawdust(PWS),grape pomace(GP),beech wood shavings(BWS),cotton cake(CK),corn cobs(CC),coffee residue(CR),olive pulp(OP),barley and oats straw(BOS)and ...The influence of ten agro-residues,i.e.,wheat straw(WS),poplar wood sawdust(PWS),grape pomace(GP),beech wood shavings(BWS),cotton cake(CK),corn cobs(CC),coffee residue(CR),olive pulp(OP),barley and oats straw(BOS)and rice bark(RB),used as alternative substrates for the cultivation of Pleurotus mushrooms,was examined during mycelial growth(colonization phase).Several native and commercial strains of P.ostreatus and P.eryngii were subjected to screening regarding their mycelial growth rates,biomass production and endoglucanase and laccase activities.The experimental results showed that the highest growth rates of P.ostreatus strains were noticed on BWS,BOS,CC and RB substrates,with the time of complete colonization varying between 16 and 36 days,whereas for P.eryngii a high linear growth rate was observed on CC,OP,CR and BOS with the colonization period ranging between 26 and 51 days.The maximum biomass production obtained on the various substrates for both Pleurotus species ranged from 115.32 to 454.42 mg/g d.w.for P.ostreatus and from 108.50 to 422.59 mg/g d.w.for P.eryngii.As for endoglucanase,the highest activities were observed in P.eryngii AMRL 163 cultures on PWS and BOS,i.e.,0.19 and 0.18 U/g d.w.,respectively.P.eryngii AMRL 173–6 and P.ostreatus AMRL 150 cultivated on RB and BOS,synthesized significant laccase amounts,i.e.,2172.28 and 1987.25 U/g d.w.,respectively.The effect of the substrate components on the growth parameters was considered and discussed.This study showed the industrial potential to convert important low-value agro-residues to fungal biomass and enzymes and eventually to valuable food products.展开更多
The greatest limitation to utilization of maize stover by ruminants as a feed is the high concentration of lignin, which limits fibre digestibility. However, ruminants can effectively utilize maize stover if its nutri...The greatest limitation to utilization of maize stover by ruminants as a feed is the high concentration of lignin, which limits fibre digestibility. However, ruminants can effectively utilize maize stover if its nutritive value is improved using white rot fungal species. This study was designed to determine optimal biophysical conditions for mycelial growth and select the most ideal fungal species and pre-treatment options for improving nutritive value of maize stover. Four popular edible Pleurotus fungal species(viz.Pleurotus florida,Pleurotus ostreatus, Pleurotus sajor caju and Pleurotus pulmonarius) were subjected to varying temperatures, pH levels, hydrogen peroxide(H_2 O_2) concentration and illumination to establish the extent of mycelial growth rate.Inclusion of H_2 O_2 was used to determine optimal levels for preservation and prevention of contamination from other indigenous microbiota. Effects of pre-treatment options on chemical composition and nutritive value of maize stover were also examined. Mycelial growth rate of Pleurotus species on potato dextrose agar(PDA) varied(P < 0.05) with temperature, pH level and H_2 O_2 concentration following a quadratic trend. Optimal temperature, pH and H_2 O_2 concentration for mycelial growth on PDA were 25 ℃,5 and 0.01 mL/L, respectively. Under the different bio-physical conditions,P. sajor caju had the highest mycelia density and growth rate. Chemical composition of solid-state fermented maize stover differed(P < 0.05) among the Pleurotus species. Maize stover fermented with P. sajor caju had the highest crude protein(CP) of 86.6 g/kg DM, in-vitro dry matter digestibility(IVDMD) of 731 g/kg DM, in-vitro organic matter digestibility(IVOMD) of 670.4 g/kg DM and metabolizable energy(ME) of10.0 MJ/kg DM but with the lowest lignin(sa) of 50 g/kg DM. At 25℃, P. sajor caju had the highest mycelial growth rate on PDA and highest lignin(sa) breakdown in the maize stover substrate. It was, therefore,selected as the most ideal fungal species for improving nutritive valu展开更多
Sclerotinia sclerotiorum is one of the most devastating necrotrophic phytopathogens. Virulence of the hyphae of this fungus at different ages varies significantly. Molecular mechanisms underlying this functional disti...Sclerotinia sclerotiorum is one of the most devastating necrotrophic phytopathogens. Virulence of the hyphae of this fungus at different ages varies significantly. Molecular mechanisms underlying this functional distinction are largely unknown. In this study, we confirmed the effect of mycelial culture time/age on virulence in two host plants and elucidated its molecular and morphological basis. The virulence of the S. sclerotiorum mycelia in plants dramatically decreases along with the increase of the mycelial age. Three-day-old mycelia lost the virulence in plants. Comparative proteomics analyses revealed that metabolism pathways were comprehensively reprogrammed to suppress the oxalic acid(OA) accumulation in old mycelia. The oxaloacetate acetylhydrolase(OAH), which catalyzes OA biosynthesis, was identified in the S. sclerotiorum genome. Both gene expression and protein accumulation of OAH in old mycelia were strongly repressed. Moreover, in planta OA accumulation was strikingly reduced in old mycelia-inoculated plants compared with young vegetative mycelia-inoculated plants. Furthermore, supply with 10 mmol L^(-1) OA enabled the old mycelia infect the host plants, demonstrating that loss of virulence of old mycelia is mainly caused by being unable to accumulate OA. Additionally, aerial mycelia started to develop from 0.5-day-old vegetative mycelia and dominated over 1-day-old mycelia grown on potato dextrose agar plates. They were much smaller in hypha diameter and grew significantly slower than young vegetative mycelia when subcultured, which did not maintain to progenies. Collectively, our results reveal that S. sclerotiorum aerial hyphae-dominant old mycelia fail to accumulate OA and thereby lose the virulence in host plants.展开更多
[ Objective] The research aimed to study effects of material physical properties on white-rot fungi mycelial growth and provide theoretical basis for further expanding the application range of white-rot fungi. [ Metho...[ Objective] The research aimed to study effects of material physical properties on white-rot fungi mycelial growth and provide theoretical basis for further expanding the application range of white-rot fungi. [ Method Four common species of white-rot fungi were cultivated by wood meal fowl dung mixture in test tube and culture dishes. The relationship between physical properties of culture material and the growth of these mycelials were studied. [Result] The results showed the water retention capacity of culture material was decreased with the increasing of its grain size and porosity, but the decrease of its specific gravity reduced the material water retention. And the dehydration rate of medium prepared with these materials at the same moisture conditions tended to increase. These physical properties of material, such as grain size, specific gravity, porosity, water retention and water drainage, influenced the growth of white-rot fungi mycelial by affecting the moisture and ventilation condition of media. The results hinted that above material physical properties had feedback effects on the growth of white-rot fungi mycelia. [ Conclution] Physical properties of culture material have significant effects on the growth of white-rot fungi mycelial.展开更多
Growth of?Paecilomyces hepiali?in various agar media and yield of fruit bodies in rice based media were?studied. The best growth in agar media was obtained at 25℃?(61.86 mm colony diameter in 14 days). The initial ag...Growth of?Paecilomyces hepiali?in various agar media and yield of fruit bodies in rice based media were?studied. The best growth in agar media was obtained at 25℃?(61.86 mm colony diameter in 14 days). The initial agar media pH range?from?6 to 8 was found to be?the?most favourable for mycelial growth. This study found that agars made with powders of cereal grains alone do not support good mycelial growth of?P. hepiali. Addition of peptone improved mycelial growth significantly. The most favourable carbon sources were Mannose, Fructose and Glucose. Organic nitrogen sources were found to be?the?most preferred. The results demonstrated that brown rice is better than polished rice in yield of fruit bodies. Addition of peptone was found to be quite significant in enhancing yield of fruit bodies. Peptone, as a supplement, gave a better yield than addition of egg yolk, albumen and a mixture of the two. The medium with?40 g brown rice, 0.325 g glucose, 0.65 g sucrose, 2 g peptone and 65 ml corn steep liquor was found to be?the?most favourable and it yielded 19.3 g of fresh fruit bodies.展开更多
Using cottonseed hull as the control substrate, different proportions of the untreated and treated Carya cathayensis Sarg shells were added to cultivation of Pleurotus geesteranus. The mycelial growth rate, yield, nut...Using cottonseed hull as the control substrate, different proportions of the untreated and treated Carya cathayensis Sarg shells were added to cultivation of Pleurotus geesteranus. The mycelial growth rate, yield, nutritional composition and contents of heavy metals of the Pleurotus geesteranus cultivated on these substrates were determined. The results suggest that added to treated Carya cathayensis Sarg shell promoted the mycelial growth and increased the yield, biological efficiency and the contents of crude fiber, ash, amino acids and essential amino acids of Pleurotus geesteranus. In addition, the fat content and soluble sugar contents of Pleurotus geesteranus were decreased with the increase of the Carya cathayensis Sarg shell content in substrate, but their contents of heavy metals including mercury (Hg), arsenic (As), cadmium (Cd) and lead (Pb) were higher than that obtained on control substrate.展开更多
To increase the efficiency of dye removal from wastewater using mycelial pellets, a bubble column reactor with a simple structure was designed and efficiently used to remove dyes from solution containing dyes. The myc...To increase the efficiency of dye removal from wastewater using mycelial pellets, a bubble column reactor with a simple structure was designed and efficiently used to remove dyes from solution containing dyes. The mycelial pellets were prepared by marine fungus Aspergillus niger ZJUBE-1. Eight dyes were tested as dye targets for the adsorption capacity of mycelial pellets and good removal results were obtained. Eriochrome black T was selected as a model dye for characterizing the adsorption processes in detail. The measurement results of Zeta potential and FT- IR analysis indicate that the electrostatic attraction may play a key role in the biosorption process. The bubble column reactor was utilized to study the batch dye-removal efficiency of mycelial pellets. A re-culture process between every two batches, which was under non-sterile condition, successfully enhanced the utilization of mycelium bio- mass. The dye removal rate is 96.4% after 12 h in the first batch and then decreases slowly in the following batches. This semi-continuous mode, which consists of commutative processes of dye-removal and re-culture, has some outstanding advantages, such as low power consumption, easy operation, high dye removal rate, and efficient biomass utilization.展开更多
The study was conducted to make clear the activity of azoxystrobin to 4 plant pathogens and the synergistic effects of salicylhydroxamic acid (SHAM), which acted on the alternative oxidase. It was also conducted to ...The study was conducted to make clear the activity of azoxystrobin to 4 plant pathogens and the synergistic effects of salicylhydroxamic acid (SHAM), which acted on the alternative oxidase. It was also conducted to be aware of the mechanism of azoxystrobin in inhibition on mycelial respiration and the influence of SHAM. The activity test of azoxystrobin and SHAM was carried out with a mycelial linear growth test and spore germination test. Other related biological properties were also observed. Inhibition of azoxystrobin and SHAM on 4 pathogens was determined by using SP-II oxygraph system. Azoxystrobin inhibited mycelial growth in Colletotrichum capsici, Botrytis cinerea, Rhizoctonia solani, and Magnaporthe grisea, respectively; it also inhibited conidia germination, and conidia production in C. capsici, B. cinerea M. grisea, and sclerotia formation in R. solani. Moreover, it created stayed pigment biosynthesis in C. capsici and M. grisea somehow. Salicylhydroxamic acid enhanced inhibition by azoxystrobin. An oxygen consuming test of the mycelia showed that azoxystrobin inhibited all the 4 fungi's respiration in the early stages. With the concentration rising up, the effectiveness increased. However, as time went on, the respiration of the mycelia treated with fungicides recovered and SHAM could not inhibit the oxygen consuming. This reaction between the mycelia and the fungicides appeared not to initiate alternative respiration but rather the other mechanism created a lack of efficacy.展开更多
[Objectives]This study was conducted to clarify the biological characteristics of the pathogen Phyllosticta capitalensis,the causal agent of freckle disease on Cavendish banana in Hainan Province,China.[Methods]The im...[Objectives]This study was conducted to clarify the biological characteristics of the pathogen Phyllosticta capitalensis,the causal agent of freckle disease on Cavendish banana in Hainan Province,China.[Methods]The impact of various nutritional and environmental factors,including media,carbon sources,nitrogen sources,temperature,pH and light on the growth and sporulation of P.capitalensis was assessed using two distinct methods:mycelium growth rate and blood counting chamber.[Results]The mycelial growth and sporulation of P.capitalensis on different media exhibited notable differences.The use of banana leaf extract dextrose agar(BLEAD)and carrot agar(CA)was observed to facilitate rapid mycelial growth.The potato dextrose agar(PDA)and potato sucrose agar(PSA)were conducive to the production of conidia.The utilization of distinct carbon and nitrogen sources exerted a pronounced influence on the growth of P.capitalensis.Maltose,dextrose,fructose,and casein acid hydrolysate were the preferred substrates for mycelial growth.The tested carbon and nitrogen sources did not significantly stimulate conidial production,whereas dextrose and NaNO 3 were found to favor sporulation.The optimal temperature for mycelial growth and conidial production was determined to be 28 and 32℃,respectively.No mycelial growth was observed at 5℃.Active mycelial growth was observed at pH 6-10,with pH 6-7 being particularly conducive to sporulation.Complete darkness was conducive to mycelial growth and sporulation.[Conclusions]It is recommended that BLEDA and PDA should be incubated at 28℃for 14 d in the dark for the purpose of mycelial growth and sporulation of P.capitalensis,respectively.展开更多
基金This work was supported by the National Natural Science Foundation of China (Grant Nos. 29876026 and 29743001).
文摘Mycelial waste of Streptomyces aureofaciences procured from the aureomycin fermentation industry is used as biosorbent for Au3+. The properties of Au3+ adsorption by the mycelial waste are studied. The results indicate that the optimum pH value of Au3+ adsorption is 3.5. The biosorption is a rapid and non-temperature-dependent process. The bio-sorptive capacity with 45.6 mg/g and efficiency with 91.2% are achieved under the conditions of pH 3.5 and 30℃ for 45 min, in which the ratio is 50 mg/g dry weight for the concentrations of initial Au3+ and the mycelial waste. The Au3+ ions adsorbed on the mycelial waste can be eluted. The observation in a transmission electron microscope shows that the Au3+ ions can be reduced to Au particles by the mycelial waste and the Au can become gold crystals with differentforms and sizes. X-ray photoelectron spectroscopy analysis further proves that the Au3+ can be reduced to Au0 by the mycelial waste.
基金supported by the Public Projects of the Ministry of Environment Protection (No. 201209024)the State Key Laboratory of Urban Water Resource and Environment at Harbin Institute of Technology (No. 2015DX10)the Program for New Century Excellent Talents in University (No. NCET-12-0156)
文摘Pilot scale experiments with forced aeration were conducted to estimate effects of aeration rates on the performance of composting penicillin mycelial dreg using sewage sludge as inoculation. Three aeration rates of 0.15, 0.50 and 0.90 L/(min·kg) organic matter(OM) were examined. The principal physicochemical parameters were monitored during the 32 day composting period. Results showed that the higher aeration rate of 0.90 L/(min·kg) did not corresponded to a longer thermophilic duration and higher rates of OM degradation;but the lower aeration rate of 0.15 L/(min·kg) did induce an accumulation of NH+4-N contents due to the inhibition of nitrification. On the other hand, aeration rate has little effect on degradation of penicillin. The results show that the longest phase of thermophilic temperatures ≥ 55°C, the maximum NO-3-N content and seed germination, and the minimum C/N ratio were obtained with 0.50 L/(min·kg) OM. Therefore, aeration rates of0.50 L/(min·kg) OM can be recommended for composting penicillin mycelial dreg.
基金Supported by the National Natural Science Foundation of China(No.21376214)
文摘In order to improve the efficient decolorization of dye-containing water by biosorbent and understand the biosorption mechanism, the self-immobilization mycelial pellets were prepared using a marine-derived fungus Aspergillus niger ZJUBE-1, and an azo dye, Congo red was chosen as a model dye to investigate batch decolorization efficiency by pellets. The pellets as biosorbent showed strong salt and acid tolerance in biosorption process. The results for dye adsorption showed that the biosorption process fitted well with models of pseudo-second-order kinetic and Langmuir isotherm, with a maximum adsorption capacity of 263.2 mg·g^(-1) mycelium. During 6 batches of continuous decolorization operation, the mycelial pellets could possess efficient decolorization abilities(>98.5%).The appearance of new peak in the UV–Vis spectral result indicated that the decolorization process may also contain biodegradation. The mechanism studies showed that efficient biosorption ability of pellets only relies on the active zone on the surface of the pellet, which can be enhanced by nutrition supplement or be shifted outward by a reculture process.
基金the European Regional Development Fund of the European Union and Greek national funds(European Social Fund–ESF)through the Operational Program Competitiveness,Entrepreneurship and Innovation,under the call RESEARCH–CREATE-INNOVATE(project code:Τ1EΔΚ-05027)scientifically coordinated by the Hellenic Agricultural Organization–DEMETER(Institute of Technology of Agricultural Products/Laboratory of Edible Fungi).
文摘The influence of ten agro-residues,i.e.,wheat straw(WS),poplar wood sawdust(PWS),grape pomace(GP),beech wood shavings(BWS),cotton cake(CK),corn cobs(CC),coffee residue(CR),olive pulp(OP),barley and oats straw(BOS)and rice bark(RB),used as alternative substrates for the cultivation of Pleurotus mushrooms,was examined during mycelial growth(colonization phase).Several native and commercial strains of P.ostreatus and P.eryngii were subjected to screening regarding their mycelial growth rates,biomass production and endoglucanase and laccase activities.The experimental results showed that the highest growth rates of P.ostreatus strains were noticed on BWS,BOS,CC and RB substrates,with the time of complete colonization varying between 16 and 36 days,whereas for P.eryngii a high linear growth rate was observed on CC,OP,CR and BOS with the colonization period ranging between 26 and 51 days.The maximum biomass production obtained on the various substrates for both Pleurotus species ranged from 115.32 to 454.42 mg/g d.w.for P.ostreatus and from 108.50 to 422.59 mg/g d.w.for P.eryngii.As for endoglucanase,the highest activities were observed in P.eryngii AMRL 163 cultures on PWS and BOS,i.e.,0.19 and 0.18 U/g d.w.,respectively.P.eryngii AMRL 173–6 and P.ostreatus AMRL 150 cultivated on RB and BOS,synthesized significant laccase amounts,i.e.,2172.28 and 1987.25 U/g d.w.,respectively.The effect of the substrate components on the growth parameters was considered and discussed.This study showed the industrial potential to convert important low-value agro-residues to fungal biomass and enzymes and eventually to valuable food products.
基金East African Agricultural Productivity Project (EAAP)National Agricultural Research Organization (NARO)the National Livestock Resources Research Institute(NaLIRRI) for the financial support during the progress of this work
文摘The greatest limitation to utilization of maize stover by ruminants as a feed is the high concentration of lignin, which limits fibre digestibility. However, ruminants can effectively utilize maize stover if its nutritive value is improved using white rot fungal species. This study was designed to determine optimal biophysical conditions for mycelial growth and select the most ideal fungal species and pre-treatment options for improving nutritive value of maize stover. Four popular edible Pleurotus fungal species(viz.Pleurotus florida,Pleurotus ostreatus, Pleurotus sajor caju and Pleurotus pulmonarius) were subjected to varying temperatures, pH levels, hydrogen peroxide(H_2 O_2) concentration and illumination to establish the extent of mycelial growth rate.Inclusion of H_2 O_2 was used to determine optimal levels for preservation and prevention of contamination from other indigenous microbiota. Effects of pre-treatment options on chemical composition and nutritive value of maize stover were also examined. Mycelial growth rate of Pleurotus species on potato dextrose agar(PDA) varied(P < 0.05) with temperature, pH level and H_2 O_2 concentration following a quadratic trend. Optimal temperature, pH and H_2 O_2 concentration for mycelial growth on PDA were 25 ℃,5 and 0.01 mL/L, respectively. Under the different bio-physical conditions,P. sajor caju had the highest mycelia density and growth rate. Chemical composition of solid-state fermented maize stover differed(P < 0.05) among the Pleurotus species. Maize stover fermented with P. sajor caju had the highest crude protein(CP) of 86.6 g/kg DM, in-vitro dry matter digestibility(IVDMD) of 731 g/kg DM, in-vitro organic matter digestibility(IVOMD) of 670.4 g/kg DM and metabolizable energy(ME) of10.0 MJ/kg DM but with the lowest lignin(sa) of 50 g/kg DM. At 25℃, P. sajor caju had the highest mycelial growth rate on PDA and highest lignin(sa) breakdown in the maize stover substrate. It was, therefore,selected as the most ideal fungal species for improving nutritive valu
基金supported by grants from the Special Fund for Agro-Scientific Research in the Public Interest, China (201103016)the Specialized Research Fund for the Doctoral Program of Higher Education, China (SRFDP) (20110101110092)+2 种基金the National Natural Science Foundation of China (31371892)the Program for New Century Excellent Talents in University (NCET-08-0485)the Program for New Century 151 Talents of Zhejiang Province, China
文摘Sclerotinia sclerotiorum is one of the most devastating necrotrophic phytopathogens. Virulence of the hyphae of this fungus at different ages varies significantly. Molecular mechanisms underlying this functional distinction are largely unknown. In this study, we confirmed the effect of mycelial culture time/age on virulence in two host plants and elucidated its molecular and morphological basis. The virulence of the S. sclerotiorum mycelia in plants dramatically decreases along with the increase of the mycelial age. Three-day-old mycelia lost the virulence in plants. Comparative proteomics analyses revealed that metabolism pathways were comprehensively reprogrammed to suppress the oxalic acid(OA) accumulation in old mycelia. The oxaloacetate acetylhydrolase(OAH), which catalyzes OA biosynthesis, was identified in the S. sclerotiorum genome. Both gene expression and protein accumulation of OAH in old mycelia were strongly repressed. Moreover, in planta OA accumulation was strikingly reduced in old mycelia-inoculated plants compared with young vegetative mycelia-inoculated plants. Furthermore, supply with 10 mmol L^(-1) OA enabled the old mycelia infect the host plants, demonstrating that loss of virulence of old mycelia is mainly caused by being unable to accumulate OA. Additionally, aerial mycelia started to develop from 0.5-day-old vegetative mycelia and dominated over 1-day-old mycelia grown on potato dextrose agar plates. They were much smaller in hypha diameter and grew significantly slower than young vegetative mycelia when subcultured, which did not maintain to progenies. Collectively, our results reveal that S. sclerotiorum aerial hyphae-dominant old mycelia fail to accumulate OA and thereby lose the virulence in host plants.
基金Supported by Qian Jiang Manpower Program of Zhejiang Province Science and Technology Department (No.2007R10039)National Basic Research Program of China (No.2005CB724204)Under-graduate Technology Innovation Program of Zhejiang Province~~
文摘[ Objective] The research aimed to study effects of material physical properties on white-rot fungi mycelial growth and provide theoretical basis for further expanding the application range of white-rot fungi. [ Method Four common species of white-rot fungi were cultivated by wood meal fowl dung mixture in test tube and culture dishes. The relationship between physical properties of culture material and the growth of these mycelials were studied. [Result] The results showed the water retention capacity of culture material was decreased with the increasing of its grain size and porosity, but the decrease of its specific gravity reduced the material water retention. And the dehydration rate of medium prepared with these materials at the same moisture conditions tended to increase. These physical properties of material, such as grain size, specific gravity, porosity, water retention and water drainage, influenced the growth of white-rot fungi mycelial by affecting the moisture and ventilation condition of media. The results hinted that above material physical properties had feedback effects on the growth of white-rot fungi mycelia. [ Conclution] Physical properties of culture material have significant effects on the growth of white-rot fungi mycelial.
文摘Growth of?Paecilomyces hepiali?in various agar media and yield of fruit bodies in rice based media were?studied. The best growth in agar media was obtained at 25℃?(61.86 mm colony diameter in 14 days). The initial agar media pH range?from?6 to 8 was found to be?the?most favourable for mycelial growth. This study found that agars made with powders of cereal grains alone do not support good mycelial growth of?P. hepiali. Addition of peptone improved mycelial growth significantly. The most favourable carbon sources were Mannose, Fructose and Glucose. Organic nitrogen sources were found to be?the?most preferred. The results demonstrated that brown rice is better than polished rice in yield of fruit bodies. Addition of peptone was found to be quite significant in enhancing yield of fruit bodies. Peptone, as a supplement, gave a better yield than addition of egg yolk, albumen and a mixture of the two. The medium with?40 g brown rice, 0.325 g glucose, 0.65 g sucrose, 2 g peptone and 65 ml corn steep liquor was found to be?the?most favourable and it yielded 19.3 g of fresh fruit bodies.
文摘Using cottonseed hull as the control substrate, different proportions of the untreated and treated Carya cathayensis Sarg shells were added to cultivation of Pleurotus geesteranus. The mycelial growth rate, yield, nutritional composition and contents of heavy metals of the Pleurotus geesteranus cultivated on these substrates were determined. The results suggest that added to treated Carya cathayensis Sarg shell promoted the mycelial growth and increased the yield, biological efficiency and the contents of crude fiber, ash, amino acids and essential amino acids of Pleurotus geesteranus. In addition, the fat content and soluble sugar contents of Pleurotus geesteranus were decreased with the increase of the Carya cathayensis Sarg shell content in substrate, but their contents of heavy metals including mercury (Hg), arsenic (As), cadmium (Cd) and lead (Pb) were higher than that obtained on control substrate.
文摘To increase the efficiency of dye removal from wastewater using mycelial pellets, a bubble column reactor with a simple structure was designed and efficiently used to remove dyes from solution containing dyes. The mycelial pellets were prepared by marine fungus Aspergillus niger ZJUBE-1. Eight dyes were tested as dye targets for the adsorption capacity of mycelial pellets and good removal results were obtained. Eriochrome black T was selected as a model dye for characterizing the adsorption processes in detail. The measurement results of Zeta potential and FT- IR analysis indicate that the electrostatic attraction may play a key role in the biosorption process. The bubble column reactor was utilized to study the batch dye-removal efficiency of mycelial pellets. A re-culture process between every two batches, which was under non-sterile condition, successfully enhanced the utilization of mycelium bio- mass. The dye removal rate is 96.4% after 12 h in the first batch and then decreases slowly in the following batches. This semi-continuous mode, which consists of commutative processes of dye-removal and re-culture, has some outstanding advantages, such as low power consumption, easy operation, high dye removal rate, and efficient biomass utilization.
基金sponsored by the National 973 Program of China (2009CB118906, 2006CB101907)the National 863 Program of China (2006AA10A211,2008AA10Z414)the National Natural Science Foundation of China (30671048, 30671384)
文摘The study was conducted to make clear the activity of azoxystrobin to 4 plant pathogens and the synergistic effects of salicylhydroxamic acid (SHAM), which acted on the alternative oxidase. It was also conducted to be aware of the mechanism of azoxystrobin in inhibition on mycelial respiration and the influence of SHAM. The activity test of azoxystrobin and SHAM was carried out with a mycelial linear growth test and spore germination test. Other related biological properties were also observed. Inhibition of azoxystrobin and SHAM on 4 pathogens was determined by using SP-II oxygraph system. Azoxystrobin inhibited mycelial growth in Colletotrichum capsici, Botrytis cinerea, Rhizoctonia solani, and Magnaporthe grisea, respectively; it also inhibited conidia germination, and conidia production in C. capsici, B. cinerea M. grisea, and sclerotia formation in R. solani. Moreover, it created stayed pigment biosynthesis in C. capsici and M. grisea somehow. Salicylhydroxamic acid enhanced inhibition by azoxystrobin. An oxygen consuming test of the mycelia showed that azoxystrobin inhibited all the 4 fungi's respiration in the early stages. With the concentration rising up, the effectiveness increased. However, as time went on, the respiration of the mycelia treated with fungicides recovered and SHAM could not inhibit the oxygen consuming. This reaction between the mycelia and the fungicides appeared not to initiate alternative respiration but rather the other mechanism created a lack of efficacy.
基金Supported by Hainan Provincial Natural Science Foundation of China(322MS114).
文摘[Objectives]This study was conducted to clarify the biological characteristics of the pathogen Phyllosticta capitalensis,the causal agent of freckle disease on Cavendish banana in Hainan Province,China.[Methods]The impact of various nutritional and environmental factors,including media,carbon sources,nitrogen sources,temperature,pH and light on the growth and sporulation of P.capitalensis was assessed using two distinct methods:mycelium growth rate and blood counting chamber.[Results]The mycelial growth and sporulation of P.capitalensis on different media exhibited notable differences.The use of banana leaf extract dextrose agar(BLEAD)and carrot agar(CA)was observed to facilitate rapid mycelial growth.The potato dextrose agar(PDA)and potato sucrose agar(PSA)were conducive to the production of conidia.The utilization of distinct carbon and nitrogen sources exerted a pronounced influence on the growth of P.capitalensis.Maltose,dextrose,fructose,and casein acid hydrolysate were the preferred substrates for mycelial growth.The tested carbon and nitrogen sources did not significantly stimulate conidial production,whereas dextrose and NaNO 3 were found to favor sporulation.The optimal temperature for mycelial growth and conidial production was determined to be 28 and 32℃,respectively.No mycelial growth was observed at 5℃.Active mycelial growth was observed at pH 6-10,with pH 6-7 being particularly conducive to sporulation.Complete darkness was conducive to mycelial growth and sporulation.[Conclusions]It is recommended that BLEDA and PDA should be incubated at 28℃for 14 d in the dark for the purpose of mycelial growth and sporulation of P.capitalensis,respectively.