The aim of the experiment was to explore the feasibility of discarded nutrient medium of Cordyceps militaris as feed in the production of laying hens. 100 g/kg, 200 g/kg, 300 g/kg of discarded nutrient medium of Cordy...The aim of the experiment was to explore the feasibility of discarded nutrient medium of Cordyceps militaris as feed in the production of laying hens. 100 g/kg, 200 g/kg, 300 g/kg of discarded nutrient medium of Cordyceps militaris were added to the basal diet of laying hens. The results showed that the optimal addition of discarded nutrient medium of Cordyceps militaris in the diet of laying hens was 10%. According to the results of measuring the conventional indicators of eggs, the weight of eggs produced by laying hens fed with discarded nutrient medium of Cordyceps militaris was higher than that of laying hens fed with ordinary laying hens. The content of interleukin-1(IL-1) in the experimental group was significantly higher than that in the control group, and the concentration of IL-1 increased by 141.5 pg/mL, which indicated that the application of discarded nutrient medium of Cordyceps militaris effectively improved the immunity of laying hens. The high-throughput analysis of the intestinal contents of the two groups of laying hens showed that the microbial population abundance of the intestinal tract of the experimental group was greater than that of control group, and the application of discarded nutrient medium of Cordyceps militaris increased the diversity of bacteria in the intestinal tract of laying hens. In addition, the sensitivity of some pathogenic bacteria in the intestinal tract of chickens to drugs was also increased, thereby reducing the use of antibiotics. The secondary utilization of discarded nutrient medium of Cordyceps militaris has great development and utilization prospects, which provided a scientific reference and basic theoretical basis for the development of discarded nutrient medium of Cordyceps militaris as feed in the production of laying hens.展开更多
040196在卤虫培养中用细菌益生素控制溶藻弧菌=Control of Vibrio alginolyticus in Artemia culture by treatment with bacterial probioticus[刊,英]/Villamil L,Figueras A,Planas M…∥Aquac..-2003,219(1/ 4).-43-56 为了测定6种...040196在卤虫培养中用细菌益生素控制溶藻弧菌=Control of Vibrio alginolyticus in Artemia culture by treatment with bacterial probioticus[刊,英]/Villamil L,Figueras A,Planas M…∥Aquac..-2003,219(1/ 4).-43-56 为了测定6种乳酸菌(LAB)菌株,乳酸和LAB的主要细胞内产物(ECPs)对卤虫培养中细菌含量的影响。展开更多
In this study,six Cordyceps militaris strains introduced to Tibet were used as experimental materials to screen the dominant C.militaris strain by comparing mycelial growth rate,fruiting body yield and growth status.T...In this study,six Cordyceps militaris strains introduced to Tibet were used as experimental materials to screen the dominant C.militaris strain by comparing mycelial growth rate,fruiting body yield and growth status.The composition of rice medium for C.militaris cultivation was optimized by orthogonal experiment.According to the results,although C.militaris strain ＂TAAAS1＂ did not exhibit the highest mycelial growth rate,it had uniform fruiting body formation and higher fruiting body yield than other strains,which suggested that C.militaris strain ＂TAAAS1＂ was most suitable for cultivation and production of C.militaris in the alpine region.The optimal rice medium for C.militaris cultivation consisted of 4 g/L pupa powder,20 g/L glucose,1.5 g/L KH_2PO_4 and 2 g/L MgSO_4.This study provided the theoretical basis for cultivation and production of C.militaris in the alpine region.展开更多
Due to industrial activities,heavy metal concentrations in aquatic systems of Mexico,are on the rise.Zooplankton,particularly rotifers,being sensitive and common components of freshwater,are widely used in ecotoxicolo...Due to industrial activities,heavy metal concentrations in aquatic systems of Mexico,are on the rise.Zooplankton,particularly rotifers,being sensitive and common components of freshwater,are widely used in ecotoxicological tests for establishing water quality criteria.Depending on the route of exposure(i.e.via medium or algal food),the toxicity of heavy metals varies.In the present study we evaluated the effect of cadmium and mercury exposed through medium and via algal food for the rotifer B.rubens.For both the heavy metals,we exposed rotifers via medium containing Chlorella at 0.5×10^(6)cells/ml or fed daily on previously exposed(1,2 and 4 h)alga to the toxicants(using 5 times the value of LC_(50)for B.rubens).For cadmium toxicity through medium,we used 3 toxicant levels(0.1,0.2 and 0.4 mg/L)and for mercury,we used 0.005,0.010 and 0.015 mg/L.Based on the LC_(50),B.rubens was 24 times more sensitive to mercury(0.035±0.002 mg/L)than cadmium.At a concentration of 0.4 mg/L,cadmium through the medium caused increased lag phase of B.rubens.When grown on Chlorella exposed for different durations to cadmium,the rotifer density decreased with the increasing duration of algal exposure to the heavy metal.When mercury was used in the medium or via algal food,the trends in the population growth of B.rubens were similar to those for cadmium.An increase in heavy metal concentration in the medium resulted in a decrease of the rate of population increase per day(r).The r varied from 0.33(in control)to 0.02 d^(-1)(in heavy metal treatment)depending on the mode of exposure though medium or via algal food.展开更多
In this study,Cordyceps militaris strain QC04 was cultivated in oat,rice,and wheat media for different time periods.We studied the effects of different cultivation media and periods on the fruiting body biomass and ac...In this study,Cordyceps militaris strain QC04 was cultivated in oat,rice,and wheat media for different time periods.We studied the effects of different cultivation media and periods on the fruiting body biomass and active components of C.militaris,aiming to provide reference for the production and utilization of C.militaris QC04.The results showed that the dry weight of the fruiting body of C.militaris was the highest in the wheat medium,moderate in the oat medium,and the lowest in the rice medium.The content of cordycepin and adenosine in the fruiting body and residual medium was higher in the oat and rice media than in the rice medium.The content of cordycepin and adenosine in fruiting body and residual medium peaked on day 55.Furthermore,the content of cordycepin in the fruiting body was lower than that in the residual medium,while the content of adenosine showed an opposite trend.The content of cordycepic acid in the rice medium was generally higher than that in the oat and wheat media.As the cultivation period extended,the fruiting body biomass declined and the content of cordycepic acid in the fruiting body increased slightly.展开更多
Cordyceps ophioglossoides is a valuable traditional medicinal material.We have found that intracellular polysaccharide(IPS) is the major biologically active ingredient in Cordyceps ophioglossoides.This study is the fi...Cordyceps ophioglossoides is a valuable traditional medicinal material.We have found that intracellular polysaccharide(IPS) is the major biologically active ingredient in Cordyceps ophioglossoides.This study is the first time to optimize the yield of IPS from Cordyceps ophioglossoides.The optimal medium for IPS production consists of glucose 54.50 g·L·1,yeast powder 25.50 g·L·1,NaH2PO4 0.4 g·L·1 and K2HPO4 0.4 g·L·1.The suggested culture conditions are 24 ℃,initial pH 4.5 with a rotary speed of 120 r·min·1 for 168 h.The yield of IPS is 737.93 mg·L·1,which is 50% higher than the yield under the conditions prior to optimization.The anti-oxidative activities of IPS in Cordyceps ophioglossoides L2 are also characterized using various in vitro assay.The anti-oxidative activity may explain the reason why IPS from Cordyceps ophioglossoides can be used to fight against neurodegenerative dis-eases and menopausal symptoms.展开更多
Rotifers are considered as one of the most important prey organisms in the culture of altricial fish larvae. However, high density rotifer culture is often problematic due to water quality problems which results in fr...Rotifers are considered as one of the most important prey organisms in the culture of altricial fish larvae. However, high density rotifer culture is often problematic due to water quality problems which results in frequent crashes. In the present study, the performance of a small-scale, continuous system was evaluated for culturing rotifers, Brachionus plicatilis, using concentrated nonviable green algae, Nannochloropsis oculeataas feed in a 160 L tank for a period of 90 days. The system configuration was simple and major components consisted of a protein skimmer and a pure oxygen delivery system. Although egg ratio increased from 3% on day 1 to 21.8% and 39.3% on days 7 and 9, respectively, rotifer growth was slow at start up and resulted in fluctuations in total number of rotifers between days 19-41. Rotifer densities remained 〈 400 until day 51 but increased at higher rates reaching 900 individuals/mL on day 55, 1,620 on day 60 and 2,127 on day 70. Rotifer density reached a maximum of 2,188 individuals/mL on day 85. Once the rotifer density exceeded 1,500 individuals/mL （day 60）, periodical harvesting （a total of 16 harvest events） produced a total of 369,920,000 rotifers corresponding to a daily production of 12,330,667 individuals/day during the next 30 days until the experiment was terminated at day 90. As a result of periodic harvesting, water makeup and continuous protein skimming, total settleable solids and NH3-N levels remained low and ranged between 4-22 mL/L and 0.4-2.2 mg/L, respectively. The authors＇ findings indicated that this inexpensive culture system can be successfully used for small-scale marine or freshwater ornamental fish production. Further work is required to minimize lag period at start-up and increase the production potential and yield by better management of suspended solids.展开更多
Entomopathogenic microorganisms occupy an important place among the alternative methods of fighting against pests insect. The fungus Beauveria bassiana is an agent naturally present in ecosystems. It has potential to ...Entomopathogenic microorganisms occupy an important place among the alternative methods of fighting against pests insect. The fungus Beauveria bassiana is an agent naturally present in ecosystems. It has potential to control pest populations. In the context of biological control, the present work aims to the study of linear growth of Beauveria bassiana on different natural environments from the food industry. They are the raw whey, water and pomace, and followed the development of the fungus through a trial production of biomass on deproteinized whey.展开更多
Cocoa pod borer （CPB） has endangered Indonesian cocoa. Use of entomopathogen in biocontrol of pests is considered to be environmentally friendly approach. Verticillium tricorpus has been reported to be a potential a...Cocoa pod borer （CPB） has endangered Indonesian cocoa. Use of entomopathogen in biocontrol of pests is considered to be environmentally friendly approach. Verticillium tricorpus has been reported to be a potential agent for controlling CPB. The aim of this research was to study the possibility in using alternative, easy and cheap media and also the role of intensity and quality of light for mass production of V. tricorpus. The experiments were laid out in split-plot design as factorial, where every combination treatment was replicated three times. Medium, in form of semi-synthetic and natural, was treated as the main plot, while light as sub-plot. Results of this study showed that for the growth and development of fungus V. tricorpus, the use of alternative natural media in form of a mixture of cocoa pod husk and maize was the best. Use of cocoa dextrose agar （CDA） as semi-synthetic medium was more suitable for the growth and development of V. tricorpus compared to potato dextrose agar （PDA）. The semi-synthetic and natural media consisted of cocoa husk and maize are suitable for cocoa production area in Indonesia, where mostly cocoa is planted in lowland area and mostly is also suitable for corn but not for potato growing. Growth of the fungus colony especially on CDA medium reached its optimum condition when using white light with the intensity of 1,000 lux. This study proved that the requirement for light quality was different between growth and development purposes. Development of V. tricorpus until the production of conidia in optimal condition was reached with the use of yellow light with the intensity of 1,000 lux.展开更多
The effects of different carbon sources(sugars) on the production and molecular properties of exopolysaccharides(EPS) were evaluated in the mycelial liquid culture of a medicinal fungus Cordyceps sinensis Cs-HK1. Gala...The effects of different carbon sources(sugars) on the production and molecular properties of exopolysaccharides(EPS) were evaluated in the mycelial liquid culture of a medicinal fungus Cordyceps sinensis Cs-HK1. Galactose or mannose was used(at 5 g·L^(-1)) as a secondary carbon source with glucose(35 g·L^(-1)) at the mass ratio of 1:7. Mannose was consumed notably since the first day of culture, but galactose was not even after glucose was exhausted.The volumetric yield of EPS in culture was increased slightly with the addition of galactose and decreased with mannose. The monosaccharide composition of EPS was also different, e.g., on day 8, the glucose contents of EPS were 76%with the addition of mannose, 59% with galactose, compared with 62% with glucose only. The molecular weight distribution of EPS was also affected by the secondary carbon source, being generally lower compared with that with glucose only. The results suggested that the addition of galactose improved the total yield of EPS in culture while mannose can improve the yield of glucan constituent of EPS.展开更多
A pyrethroid insecticide-degrading bacterium, strain HS-24, was isolated from an offshore seawater environment. The strain, which can degrade cypermethrin （CYP） and deltamethrin （DEL）, was identified as Methylopha...A pyrethroid insecticide-degrading bacterium, strain HS-24, was isolated from an offshore seawater environment. The strain, which can degrade cypermethrin （CYP） and deltamethrin （DEL）, was identified as Methylophaga sp. The optimal culture and degradation conditions for CYP and DEL by strain HS-24 is pH 7 at 28℃. Under optimum culture conditions, strain HS-24 exhibited a broad degradation concentration range of 100, 200, 400, 600, and 800 mg/L for CYP and DEL. The metabolic intermediates were analyzed by NMR, which provided strong evidence that CYP and DEL removal occurred mainly because of a biological process. The toxicity of the degradation products of strain HS-24 was studied simultaneously by measuring the light output of the luminescence bacterium. This demonstrated that the biodegradation ability of strain HS-24 significantly decreased the toxicity of CYP- and DEL-contaminated aquaculture seawater. Finally, the findings of this paper indicate that strain HS-24 is thus revealed as a biological agent for the remediation of marine aquatic environments.展开更多
The efficacy of Bacillus cereus X5 as a potential biological control agent against root-knot nematodes was evaluated in vitro by examining second-stage juvenile mortality and egg hatching rate under addition of cultur...The efficacy of Bacillus cereus X5 as a potential biological control agent against root-knot nematodes was evaluated in vitro by examining second-stage juvenile mortality and egg hatching rate under addition of culture filtrate and in planta by application of bio-organic fertilizers enhanced with B. cereus X5, B. thuringiensis BTG, or Trichoderma harzianum SQR-T037 alone or together in greenhouse and field experiments. The biofumigation of the root-knot nematode-infested soil with organic materials (chicken manure, pig manure and rice straw) alone or in combination with B. cereus X5 was also conducted in greenhouse experiments. In laboratory, the filtrate of B. cereus X5 more effectively reduced egg hatching rates during the incubation period for 14 d and more effectively killed the second-stage juvenile during the incubation period of 24 h than that of B. thuringiensis BTG. The highest dry shoot weights for greenhouse tomatoes and field muskmelons were found in both the treatment consisting of the bio-organic fertilizer enhanced with the three biocontrol agents and the treatment consisting of the bio-organic fertilizer enhanced only with B. cereus X5. The two bio-organic fertilizers achieved better nematicidal effects than those enhanced only with B. thuringiensis BTG or T. harzianum SQR-T037. B. cereus X5 also enhanced effect of biofumigation, which resulted in increased plant biomass and reduced nematode counts in the roots and rhizosphere soil. Therefore, these results suggested that biological control of root-knot nematodes both in greenhouses and fields could be effectively achieved by using B. cereus X5 and agricultural wastes.展开更多
基金Project supported by Key Project of Education Department of Liaoning Province(LJKZZ20220116)Surface Project of Science and Technology Department of Liaoning Province(2023-MS-251).
文摘The aim of the experiment was to explore the feasibility of discarded nutrient medium of Cordyceps militaris as feed in the production of laying hens. 100 g/kg, 200 g/kg, 300 g/kg of discarded nutrient medium of Cordyceps militaris were added to the basal diet of laying hens. The results showed that the optimal addition of discarded nutrient medium of Cordyceps militaris in the diet of laying hens was 10%. According to the results of measuring the conventional indicators of eggs, the weight of eggs produced by laying hens fed with discarded nutrient medium of Cordyceps militaris was higher than that of laying hens fed with ordinary laying hens. The content of interleukin-1(IL-1) in the experimental group was significantly higher than that in the control group, and the concentration of IL-1 increased by 141.5 pg/mL, which indicated that the application of discarded nutrient medium of Cordyceps militaris effectively improved the immunity of laying hens. The high-throughput analysis of the intestinal contents of the two groups of laying hens showed that the microbial population abundance of the intestinal tract of the experimental group was greater than that of control group, and the application of discarded nutrient medium of Cordyceps militaris increased the diversity of bacteria in the intestinal tract of laying hens. In addition, the sensitivity of some pathogenic bacteria in the intestinal tract of chickens to drugs was also increased, thereby reducing the use of antibiotics. The secondary utilization of discarded nutrient medium of Cordyceps militaris has great development and utilization prospects, which provided a scientific reference and basic theoretical basis for the development of discarded nutrient medium of Cordyceps militaris as feed in the production of laying hens.
文摘040196在卤虫培养中用细菌益生素控制溶藻弧菌=Control of Vibrio alginolyticus in Artemia culture by treatment with bacterial probioticus[刊,英]/Villamil L,Figueras A,Planas M…∥Aquac..-2003,219(1/ 4).-43-56 为了测定6种乳酸菌(LAB)菌株,乳酸和LAB的主要细胞内产物(ECPs)对卤虫培养中细菌含量的影响。
文摘In this study,six Cordyceps militaris strains introduced to Tibet were used as experimental materials to screen the dominant C.militaris strain by comparing mycelial growth rate,fruiting body yield and growth status.The composition of rice medium for C.militaris cultivation was optimized by orthogonal experiment.According to the results,although C.militaris strain ＂TAAAS1＂ did not exhibit the highest mycelial growth rate,it had uniform fruiting body formation and higher fruiting body yield than other strains,which suggested that C.militaris strain ＂TAAAS1＂ was most suitable for cultivation and production of C.militaris in the alpine region.The optimal rice medium for C.militaris cultivation consisted of 4 g/L pupa powder,20 g/L glucose,1.5 g/L KH_2PO_4 and 2 g/L MgSO_4.This study provided the theoretical basis for cultivation and production of C.militaris in the alpine region.
基金This research was funded by a grant from PAPIIT—IN204101.SSSS and SN also thank National System of Investigators(SNI一18723&20520)
文摘Due to industrial activities,heavy metal concentrations in aquatic systems of Mexico,are on the rise.Zooplankton,particularly rotifers,being sensitive and common components of freshwater,are widely used in ecotoxicological tests for establishing water quality criteria.Depending on the route of exposure(i.e.via medium or algal food),the toxicity of heavy metals varies.In the present study we evaluated the effect of cadmium and mercury exposed through medium and via algal food for the rotifer B.rubens.For both the heavy metals,we exposed rotifers via medium containing Chlorella at 0.5×10^(6)cells/ml or fed daily on previously exposed(1,2 and 4 h)alga to the toxicants(using 5 times the value of LC_(50)for B.rubens).For cadmium toxicity through medium,we used 3 toxicant levels(0.1,0.2 and 0.4 mg/L)and for mercury,we used 0.005,0.010 and 0.015 mg/L.Based on the LC_(50),B.rubens was 24 times more sensitive to mercury(0.035±0.002 mg/L)than cadmium.At a concentration of 0.4 mg/L,cadmium through the medium caused increased lag phase of B.rubens.When grown on Chlorella exposed for different durations to cadmium,the rotifer density decreased with the increasing duration of algal exposure to the heavy metal.When mercury was used in the medium or via algal food,the trends in the population growth of B.rubens were similar to those for cadmium.An increase in heavy metal concentration in the medium resulted in a decrease of the rate of population increase per day(r).The r varied from 0.33(in control)to 0.02 d^(-1)(in heavy metal treatment)depending on the mode of exposure though medium or via algal food.
基金Supported by Guizhou Province Science and Technology Major Project(Qiankehe Major Special Project[2019]3007-6)Guizhou Province Science and Technology Support Plan Project(Qiankehe Support[2019]2773)Guizhou Province Reform and Transformation Plan Project(Qiankehe Z Word[2013]4006)。
文摘In this study,Cordyceps militaris strain QC04 was cultivated in oat,rice,and wheat media for different time periods.We studied the effects of different cultivation media and periods on the fruiting body biomass and active components of C.militaris,aiming to provide reference for the production and utilization of C.militaris QC04.The results showed that the dry weight of the fruiting body of C.militaris was the highest in the wheat medium,moderate in the oat medium,and the lowest in the rice medium.The content of cordycepin and adenosine in the fruiting body and residual medium was higher in the oat and rice media than in the rice medium.The content of cordycepin and adenosine in fruiting body and residual medium peaked on day 55.Furthermore,the content of cordycepin in the fruiting body was lower than that in the residual medium,while the content of adenosine showed an opposite trend.The content of cordycepic acid in the rice medium was generally higher than that in the oat and wheat media.As the cultivation period extended,the fruiting body biomass declined and the content of cordycepic acid in the fruiting body increased slightly.
基金Supported by the National High Technology Research and Development Program of China (2007AA021506)the Natural Science Foundation of Zhejiang Province (R207609)the Research Project of Science and Technology of Zhejiang Province,China (2005C23027)
文摘Cordyceps ophioglossoides is a valuable traditional medicinal material.We have found that intracellular polysaccharide(IPS) is the major biologically active ingredient in Cordyceps ophioglossoides.This study is the first time to optimize the yield of IPS from Cordyceps ophioglossoides.The optimal medium for IPS production consists of glucose 54.50 g·L·1,yeast powder 25.50 g·L·1,NaH2PO4 0.4 g·L·1 and K2HPO4 0.4 g·L·1.The suggested culture conditions are 24 ℃,initial pH 4.5 with a rotary speed of 120 r·min·1 for 168 h.The yield of IPS is 737.93 mg·L·1,which is 50% higher than the yield under the conditions prior to optimization.The anti-oxidative activities of IPS in Cordyceps ophioglossoides L2 are also characterized using various in vitro assay.The anti-oxidative activity may explain the reason why IPS from Cordyceps ophioglossoides can be used to fight against neurodegenerative dis-eases and menopausal symptoms.
文摘Rotifers are considered as one of the most important prey organisms in the culture of altricial fish larvae. However, high density rotifer culture is often problematic due to water quality problems which results in frequent crashes. In the present study, the performance of a small-scale, continuous system was evaluated for culturing rotifers, Brachionus plicatilis, using concentrated nonviable green algae, Nannochloropsis oculeataas feed in a 160 L tank for a period of 90 days. The system configuration was simple and major components consisted of a protein skimmer and a pure oxygen delivery system. Although egg ratio increased from 3% on day 1 to 21.8% and 39.3% on days 7 and 9, respectively, rotifer growth was slow at start up and resulted in fluctuations in total number of rotifers between days 19-41. Rotifer densities remained 〈 400 until day 51 but increased at higher rates reaching 900 individuals/mL on day 55, 1,620 on day 60 and 2,127 on day 70. Rotifer density reached a maximum of 2,188 individuals/mL on day 85. Once the rotifer density exceeded 1,500 individuals/mL （day 60）, periodical harvesting （a total of 16 harvest events） produced a total of 369,920,000 rotifers corresponding to a daily production of 12,330,667 individuals/day during the next 30 days until the experiment was terminated at day 90. As a result of periodic harvesting, water makeup and continuous protein skimming, total settleable solids and NH3-N levels remained low and ranged between 4-22 mL/L and 0.4-2.2 mg/L, respectively. The authors＇ findings indicated that this inexpensive culture system can be successfully used for small-scale marine or freshwater ornamental fish production. Further work is required to minimize lag period at start-up and increase the production potential and yield by better management of suspended solids.
文摘Entomopathogenic microorganisms occupy an important place among the alternative methods of fighting against pests insect. The fungus Beauveria bassiana is an agent naturally present in ecosystems. It has potential to control pest populations. In the context of biological control, the present work aims to the study of linear growth of Beauveria bassiana on different natural environments from the food industry. They are the raw whey, water and pomace, and followed the development of the fungus through a trial production of biomass on deproteinized whey.
文摘Cocoa pod borer （CPB） has endangered Indonesian cocoa. Use of entomopathogen in biocontrol of pests is considered to be environmentally friendly approach. Verticillium tricorpus has been reported to be a potential agent for controlling CPB. The aim of this research was to study the possibility in using alternative, easy and cheap media and also the role of intensity and quality of light for mass production of V. tricorpus. The experiments were laid out in split-plot design as factorial, where every combination treatment was replicated three times. Medium, in form of semi-synthetic and natural, was treated as the main plot, while light as sub-plot. Results of this study showed that for the growth and development of fungus V. tricorpus, the use of alternative natural media in form of a mixture of cocoa pod husk and maize was the best. Use of cocoa dextrose agar （CDA） as semi-synthetic medium was more suitable for the growth and development of V. tricorpus compared to potato dextrose agar （PDA）. The semi-synthetic and natural media consisted of cocoa husk and maize are suitable for cocoa production area in Indonesia, where mostly cocoa is planted in lowland area and mostly is also suitable for corn but not for potato growing. Growth of the fungus colony especially on CDA medium reached its optimum condition when using white light with the intensity of 1,000 lux. This study proved that the requirement for light quality was different between growth and development purposes. Development of V. tricorpus until the production of conidia in optimal condition was reached with the use of yellow light with the intensity of 1,000 lux.
基金Supported by The Hong Kong Polytechnic University internal grants(G-UC14 and G-YBB4)
文摘The effects of different carbon sources(sugars) on the production and molecular properties of exopolysaccharides(EPS) were evaluated in the mycelial liquid culture of a medicinal fungus Cordyceps sinensis Cs-HK1. Galactose or mannose was used(at 5 g·L^(-1)) as a secondary carbon source with glucose(35 g·L^(-1)) at the mass ratio of 1:7. Mannose was consumed notably since the first day of culture, but galactose was not even after glucose was exhausted.The volumetric yield of EPS in culture was increased slightly with the addition of galactose and decreased with mannose. The monosaccharide composition of EPS was also different, e.g., on day 8, the glucose contents of EPS were 76%with the addition of mannose, 59% with galactose, compared with 62% with glucose only. The molecular weight distribution of EPS was also affected by the secondary carbon source, being generally lower compared with that with glucose only. The results suggested that the addition of galactose improved the total yield of EPS in culture while mannose can improve the yield of glucan constituent of EPS.
基金Supported by the Social Development Fund of Science and Technology Department of Zhejiang Province(No.2013C33091)the Scientific Research Fund of Ningbo University(Nos.xkl11D2098,xkl11091)+1 种基金the National Natural Science Foundation of China(No.31001139)the K.C.Wong Magna Fund of Ningbo University
文摘A pyrethroid insecticide-degrading bacterium, strain HS-24, was isolated from an offshore seawater environment. The strain, which can degrade cypermethrin （CYP） and deltamethrin （DEL）, was identified as Methylophaga sp. The optimal culture and degradation conditions for CYP and DEL by strain HS-24 is pH 7 at 28℃. Under optimum culture conditions, strain HS-24 exhibited a broad degradation concentration range of 100, 200, 400, 600, and 800 mg/L for CYP and DEL. The metabolic intermediates were analyzed by NMR, which provided strong evidence that CYP and DEL removal occurred mainly because of a biological process. The toxicity of the degradation products of strain HS-24 was studied simultaneously by measuring the light output of the luminescence bacterium. This demonstrated that the biodegradation ability of strain HS-24 significantly decreased the toxicity of CYP- and DEL-contaminated aquaculture seawater. Finally, the findings of this paper indicate that strain HS-24 is thus revealed as a biological agent for the remediation of marine aquatic environments.
基金Supported by the National Basic Research Program(973 Program) of China(No.2011CB100503)the National Department Public Benefit Research Foundation of China(No.201103004)
文摘The efficacy of Bacillus cereus X5 as a potential biological control agent against root-knot nematodes was evaluated in vitro by examining second-stage juvenile mortality and egg hatching rate under addition of culture filtrate and in planta by application of bio-organic fertilizers enhanced with B. cereus X5, B. thuringiensis BTG, or Trichoderma harzianum SQR-T037 alone or together in greenhouse and field experiments. The biofumigation of the root-knot nematode-infested soil with organic materials (chicken manure, pig manure and rice straw) alone or in combination with B. cereus X5 was also conducted in greenhouse experiments. In laboratory, the filtrate of B. cereus X5 more effectively reduced egg hatching rates during the incubation period for 14 d and more effectively killed the second-stage juvenile during the incubation period of 24 h than that of B. thuringiensis BTG. The highest dry shoot weights for greenhouse tomatoes and field muskmelons were found in both the treatment consisting of the bio-organic fertilizer enhanced with the three biocontrol agents and the treatment consisting of the bio-organic fertilizer enhanced only with B. cereus X5. The two bio-organic fertilizers achieved better nematicidal effects than those enhanced only with B. thuringiensis BTG or T. harzianum SQR-T037. B. cereus X5 also enhanced effect of biofumigation, which resulted in increased plant biomass and reduced nematode counts in the roots and rhizosphere soil. Therefore, these results suggested that biological control of root-knot nematodes both in greenhouses and fields could be effectively achieved by using B. cereus X5 and agricultural wastes.
