Large amounts ofFlaveria bidentis's root culturing solution were obtained by using DFT (deep flow technique) equipment and these solution which was vacuum concentrated (10, 20 mg mL-~) can have a certain inhibiti...Large amounts ofFlaveria bidentis's root culturing solution were obtained by using DFT (deep flow technique) equipment and these solution which was vacuum concentrated (10, 20 mg mL-~) can have a certain inhibition on Triticum aestivum, Cucumis sativus, Raphanus sativus, Amaranthus retroflexus, Setaria viridis, Chenopodium album, Echinochloa crusgalli and Chloris virgata. This outcome suggested some active compounds in the root exudates ofFIaveria bidentis can inhibit the germination, seedling elongation and root length. The dichloromethane extract of root exudates was identificated by GC-MS, and 29 kinds of compounds, including esters, hydrocarbons, ketones, thiazole, amines, etc. were obtained and the phthalate n-octyl ester, phthalate 2-ethylhexyl ester were proved to be allelochemicals. The culturing solution of root exudates was separated through the resin column and silica gel column and a component inhibiting seedling height, root length and fresh weight of wheat was got. There were 6 kinds of organic compounds in this component including dioctyl phthalate, 1,2-phthalate, mono(2-ethylhexyl) ester by GC-MS.展开更多
[Objectives]This study aimed to investigate the pathogenicity,growth characteristics and drug resistance of Streptococcus suis type 2.[Methods]Bacterial isolation and identification,biochemical experiments,determinati...[Objectives]This study aimed to investigate the pathogenicity,growth characteristics and drug resistance of Streptococcus suis type 2.[Methods]Bacterial isolation and identification,biochemical experiments,determination of growth curve and correlation curve between OD 600 values and viable counts,drug susceptibility tests,pathogenicity analysis,and histopathological observations were carried out.[Results]The Streptococcus strain isolated from infected pigs was identified as Streptococcus suis type 2,which was named TA01 strain.TA01 strain reached the growth peak at 6-8 h post-incubation,and viable counts gradually declined after 8 h of incubation.The correlation equation between OD 600 values and viable counts is y=24.659 x-1.076 1,R^2=0.996 7.TA01 strain was sensitive to penicillin,erythromycin,florfenicol and oxacillin,and resistant to ciprofloxacin,polymyxin B and clindamycin.According to the results of pathogenicity analysis,all the mice in 3.6×10^9 cfu/mouse group died within 48,and these dead mice exhibited acute pyaemia septica.Based on the Reed-Muench formula,it was calculated that LD 50 of TA01 strain was 1.137×10^8 cfu/mouse.Pathological examination showed obvious blue-stained bacteria clusters,accompanied by neutrophil infiltration.[Conclusions]TA01 strain was a virulent strain of Streptococcus suis type 2.Compared with Streptococcus strains which were isolated and reported in China,TA01 strain exhibited strong virulence and rapid proliferation.展开更多
[ Objective] To screen suitable lactic acid bacterium strains from forage corn which can be used as silage additives. [ Method] The lactic acid bacterium strains were isolated by inoculation on MRS solid medium contai...[ Objective] To screen suitable lactic acid bacterium strains from forage corn which can be used as silage additives. [ Method] The lactic acid bacterium strains were isolated by inoculation on MRS solid medium containing calcium carbonate, and they were preliminarily identified through morphological, physiological and biochemical experiments. The acid production efficiency was determined. Twelve strains having strong acid-pro- duction ability were selected, and their salt tolerance and acid tolerance were detected. The sequences of their 16 S rDNA were also analyzed. [ Result] A total of 44 lactic acid bacterium strains were isolated from the forage com. As evidenced by the physiological and biochemical experi- ments, the twelve strains having strong acid-production ability belonged to Leuconostoc, Lactobacillus and Enterococcus, respectively, and they had strong salt tolerance and acid tolerance. According to the sequences of 16 S rDNA, A4, B9, B11, B12 and B14 were Lactobacillus plantarum; A1, A2., A7, A11 and B8 were Leuconostoc mesenteroides dextran subspecies; and AB and A9 were Enterococcus hirae. [ Conclusion ] The lactic acid bacterium strains with strong acid-production ability isolated from forage corn can be developed into silage additives.展开更多
A survey on isolation and detection of the casual organism of bacterial grain rot of rice was conducted during 1997-2006. In 2006, six pathogenic bacterial strains were isolated from two symptomless seed samples of ri...A survey on isolation and detection of the casual organism of bacterial grain rot of rice was conducted during 1997-2006. In 2006, six pathogenic bacterial strains were isolated from two symptomless seed samples of rice (Oryza sativa L.) originally produced in Hainan Province and then planted in Zhejiang Province, China. They were identified as Burkholderia glumae which is the causal organism of bacterial grain rot of rice by physiological characteristics, colony morphology, pathogenicity test, Biolog, fatty acid methyl ester (FAME) analysis and RAPD-PCR compared with the four standard reference strains. It is confirmed that there is the infection of B. glumae in so-called 'health looking seeds'.展开更多
Five strains of alginate-degrading bacteria Were isolated from the decaying parts of Laminria japonicaand Undaria pinnatifida and identified as Alteromonas espejiana (Strain A101, A102, A103, A105 ) and Alteromonas ma...Five strains of alginate-degrading bacteria Were isolated from the decaying parts of Laminria japonicaand Undaria pinnatifida and identified as Alteromonas espejiana (Strain A101, A102, A103, A105 ) and Alteromonas macleodii(Strain A104). When incubated at 25 t for 144 h in the liquid mediuxn which contamed 0. 5%peptone, 0. 3% -0. 6%sodium alginate, 0. 1 % yeast extract, 3% NaCI, pH 7. 5, the stain A102 pnduced the highest amount of alginase.展开更多
In order to understand the composition and structure of herbicidal active substance from the root of Flaveria bidentis (L.) Kuntze, the isolation and structural identification were researched in this paper. The crud...In order to understand the composition and structure of herbicidal active substance from the root of Flaveria bidentis (L.) Kuntze, the isolation and structural identification were researched in this paper. The crude extract from the root ofF. bidentis (L.) Kuntze was extracted by petroleum ether, ethyl acetate, and water saturation of n-butyl alcohol, respectively, and the extraction fluid was separated by using the method of TLC, then the main fraction was separated by HPLC, and the structure of the herbicidal active substance was analyzed by LC-MS, elemental analysis and ~H-NMR. The results showed that the petroleum extraction had the strongest herbicidal activity, and the purple blue stripe separated by TLC had the strongest effect on Digitaria sanguinalis. The herbicidal active substance was identified as ct-terthienyl according to the data of LC-MS, elemental analysis and 1H-NMR.展开更多
[ Objective] The aim of this study was to determine and analyze the pathogen and the reasons of duck viral hepatitis which is prevalent recently and difficult to control. [Method] Viruses were isolated from livers and...[ Objective] The aim of this study was to determine and analyze the pathogen and the reasons of duck viral hepatitis which is prevalent recently and difficult to control. [Method] Viruses were isolated from livers and spleens of ducks with typical clinical symptoms in Linyi, Weifang, Binzhou and other regions of Shandong Province. The pathogenic characteristics were observed by inoculation in chicken or duck embryo, RT- PCR, serological test, and duck regression. [ Result] Four duck hepatitis virus (DHV) strains were isolated, and the 5th passage allantoic fluid contained 10^3.41 -10^5.20 ELD50/mI. The serum cross protection rate was 20% -80% between the DHV stains and DHV type I. The mortalities of 4- day-old healthy ducks challenged by these four stains were 50% -100%. All challenged ducks had typical lesions of duck viral hepatitis, and the death peak appeared after 24-48 h. [Conclusion] The virulence of different DHV isolates has regional difference.展开更多
In this study, bioassay-guided isolation, identification and biological evaluation of antioxidant components from total flavonoids of Chinese herbal plant Mimenghua were performed. 1, 1-Diphenyl-2-picrylhydrazyl(DPPH)...In this study, bioassay-guided isolation, identification and biological evaluation of antioxidant components from total flavonoids of Chinese herbal plant Mimenghua were performed. 1, 1-Diphenyl-2-picrylhydrazyl(DPPH) radical scavenging test was adopted as the bioassay-guided method, Sephadex LH-20 column chromatography and high performance liquid chromatography were used as the purification tools for the acquisition of antioxidant components. One compound was obtained and identified as acteoside by its physicochemical properties and spectral characteristics. Antioxidant activity in vitro of acteoside was determined by evaluation of the scavenging activity on DPPH radical and hydroxyl radical, reducing power and total antioxidant capability.The results showed that acteoside had significant antioxidative activity and possessed higher activity with the increase of concentration, which provides the potential application of acteoside in food, pharmaceutical and cosmetic industries.展开更多
In May 2016,an epizootic occured among cultured tongue soles caused mass deaths in a fish farm in Qinhuangdao,China.In order to find out the etiological agent,a bacterial strain was isolated from ascites and other tis...In May 2016,an epizootic occured among cultured tongue soles caused mass deaths in a fish farm in Qinhuangdao,China.In order to find out the etiological agent,a bacterial strain was isolated from ascites and other tissues of sick tongue sole aseptically collected.The isolate was identified as Photobacterium damselae subsp.damsela(PDD) by isolation culture,Gram staining,physiological identification,morohological observation,biochemical identification and 16S rDNA sequence analysis.The results showed that the isolate shared 99.6% homology with the reference strain in GenBank.The animal regression test displayed that the isolate had very strong pathogenicity to tongue sole.The LD(50) was 3.1 × 10~4 CFU/mL,and it showed pathogenicity to mammals.The antimicrobial susceptibility test showed the isolate was highly sensitive to nrofloxacin,Norfloxacin,Ciprofloxacin,Mequindox;moderately sensitive to Cefradine,Doxycycline;and insensitive to Gentamicin,Ceftriaxone,Tilmicosin,etc..展开更多
Objective\ To understand the transcription of BamHI L DNA fragment from genome of strong virulent GA strain of Marek′s disease herpesvirus (MDV) in lymphoblastoid tumor tissue induced by oncogenic strain Beijing 1 ...Objective\ To understand the transcription of BamHI L DNA fragment from genome of strong virulent GA strain of Marek′s disease herpesvirus (MDV) in lymphoblastoid tumor tissue induced by oncogenic strain Beijing 1 (a specific local strain in China) of MDV. Methods\ Two oligonucleotide primers were synthesized according to the reported sequence of \%meq\% gene an ideal oncogenic candidate and our previously determined sequence of BamHI L fragment of Marek′s disease herpesvirus (MDV), respectively. Reverse transcriptase PCR(RT PCR) assay was performed by using these primers and the mRNA as a template which was isolated from visceral lymphoblastoid tumors obtained from chickens artificially infected with strain Beijing 1 of oncogenic MDV. Southern blot molecular hybridization was further carried out to detect the product of RT PCR with digoxigenin labeled nucleotide probe from BamHI I2 and L fragment in the gene library of MDV strain GA, respectively. Results\ Two probes could simultaneously hybridize this cDNA amplified by RT PCR with a length of about 730 bp. Conclusion\ It is suggested that \%meq\% transcription could extend from the right hand end of BamHI I2 to the adjacent BamHI L, and the BamHI L region was likely to be transcribed in MDV induced lymphoblastoid tumors.展开更多
Flavotoxin A was isolated from Pseudomonas cocovenenans subsp. farinofermentans culture in semisolid potato-dextrose-agar medium, which was isolated from fermented corn meal that had caused food poisoning outbreaks in...Flavotoxin A was isolated from Pseudomonas cocovenenans subsp. farinofermentans culture in semisolid potato-dextrose-agar medium, which was isolated from fermented corn meal that had caused food poisoning outbreaks in China. The isolation, purification, and chemical structure of this toxin were studied. The NMR spectra, the uv spectra, and molar extinction coefficients, and the mass spectra of Flavotoxin A are in good agreement with those reported for bongkrekic acid. Therefore, Flavotoxin A and bongkrekic acid are the same organic chemical compound; the molecular formula is C_(28)H_(38)O_7. The oral LD_(50) of the purified Flavotoxin A in mice was 3.16mg/kg (1.53-6.15mg/kg). The existence of bongkrekic acid in toxic fermented corn samples collected during food poisoning outbreaks was also confirmed. It is concluded that bongkrekic acid has played an important role in the outbreaks of fermented corn poisoning. 1989 Academic Press, Inc.展开更多
In the introduction and propagation of red sandalwood (Pterocarpus santalinus), a serious leaf disease of its seedlings in winter and spring seasons was found, but the name of the disease and its pathogen species ha...In the introduction and propagation of red sandalwood (Pterocarpus santalinus), a serious leaf disease of its seedlings in winter and spring seasons was found, but the name of the disease and its pathogen species have not been reported. The pathogen isolated from infected leaves of 18-month-old seedlings was identi- fied as Colletotrichum gloeosporioides by morphological characteristics of colony and conidium, and analysis results of rDNA-intemal transcribed spacer sequence (ITS) of the strain. Pathogenicity test results further confirmed that C. gloeosporioides was the pathogen responsible for the infected leaves symptoms of red sandal- wood. However, the disease belongs to an atypical anthraenose. Control of the leaf diseases of red sandalwood seedlings was discussed.展开更多
This experiment was conducted to clarify species and drug resistance of pathogen from the diseased Procambarus clarkia. Pathogenic bacteria from hepatopancreas of the diseased P. clarkia were examined using convention...This experiment was conducted to clarify species and drug resistance of pathogen from the diseased Procambarus clarkia. Pathogenic bacteria from hepatopancreas of the diseased P. clarkia were examined using conventional methods,and then were isolated. The further tests and analysis of the isolated strain were developed,including the regression experiment to P. clarkia,the morphology,physiological and biochemical characteristics,sequence analysis of their 16 S rRNA and gyr B genes,and the susceptibility test to antibiotics. Large colonies with similar morphology and color were obtained. Strain X120523 was identified as Citrobacter freundii,proved to have strong pathogenicity,and was susceptible to quinolones and aminoglycosides.展开更多
The neuroexcitotoxic nonprotein amino acid β-N-oxalo-L-α, β-diaminopropionic acid (β-N-ODAP)and its isomer a-N-oxalo-L-α, β-diaminopropionic acid (α-N-ODAP)in Panax ginseng C. A. Meyer(cultivated ih Northeaster...The neuroexcitotoxic nonprotein amino acid β-N-oxalo-L-α, β-diaminopropionic acid (β-N-ODAP)and its isomer a-N-oxalo-L-α, β-diaminopropionic acid (α-N-ODAP)in Panax ginseng C. A. Meyer(cultivated ih Northeastern China), Panax quinquefolius L., Panax notoginseng F.H. Chen (cultivated in Southwestern China), Korean red ginseng and Jilin red ginseng were isolated and identified. Efficient separation and purification methods for β-N-ODAP and α-N-ODAP were developed.展开更多
In this study, the liver, kidney and spleen tissues were collected from pigs with suspected PR in a pig farm in Jiangyan District, Taizhou City for virus isolation and identification. The isolated virus was inoculated...In this study, the liver, kidney and spleen tissues were collected from pigs with suspected PR in a pig farm in Jiangyan District, Taizhou City for virus isolation and identification. The isolated virus was inoculated onto PK15 monolayer cells. The virus culture was collected to extract genomic DNA for PCR assay and indirect immunoinfluscent assay. The results showed that the isolated virus was porcine pseudorabies virus, which was named TAIZ130417. The growth titer of the isolated virus reached 10 8.12 TCID 50 /ml on PK15 cells. Rabbits inoculated with the isolated virus soon exhibited pseudorabies symptoms such as itching and eventually died. The results provided reference for in-depth research and scientific prevention and control of pseudorabies.展开更多
Pasteurella species is considered the principal pathogen of the respiratory tract.Mannheimia haemolytica and Pasteurella multocida were investigated and typed from nasal swabs and tissues taken from sheep,goat and cat...Pasteurella species is considered the principal pathogen of the respiratory tract.Mannheimia haemolytica and Pasteurella multocida were investigated and typed from nasal swabs and tissues taken from sheep,goat and cattle.Indeed,41 lung and 121 nasal swabs samples were collected from animals with respiratory diseases during 2015 to 2017 in six different regions in Morocco.At first,a screening of Pasteurella species using the real time PCR(RT-PCR)was carried out,then all isolated strains on agar blood were confirmed by PCR gel based assay specific for M.haemolytica and P.multocida.Pathogenicity was evaluated in mice and histopathological examination was done on some of lung tissue.The results revealed that 34 samples of which 28(55%)from nasal swabs and six(38%)from lungs were positive for M.haemolytica and nine samples of which seven(14%)from nasal swabs and two(13%)from lungs were positive on P.multocida serogroup A.Seventy-two percent(72%)isolates were highly pathogenic to mice,which is in accordance with the results obtained by histopathology examination.This is the first report for widespread infections of Pasteurella(M.haemolytica&P.multocida)in ruminants in Morocco.Therefore,measures including development of vaccines are highly required to mitigate the impact of the bacteria in animals.展开更多
To identify the member of the caspase family proteases involved in γ radiation induced apoptosis in HL 60 cells, using degenerated oligonucleotide primers encoding the highly conserved peptides, which were present...To identify the member of the caspase family proteases involved in γ radiation induced apoptosis in HL 60 cells, using degenerated oligonucleotide primers encoding the highly conserved peptides, which were present in all known caspases, RT PCR was performed on poly (A) RNA from the γ radiation induced apoptotic HL 60 cells. Then, cloned and sequenced to identify the amplified DNA fragments. The results showed that the amplified DNA fragments were identified with a part of caspase 3 cDNA. It indicated that caspase 3 was involved in γ radiation induced apoptosis in HL 60 cells and may be the pivotal element of radiation induced apoptosis.展开更多
[Objective]The paper was to isolate and identify Botrytis cinerea from processing tomato.[Method]The strain nky007a was isolated and purified from fruits infected by tomato grey mold.After identification,it was determ...[Objective]The paper was to isolate and identify Botrytis cinerea from processing tomato.[Method]The strain nky007a was isolated and purified from fruits infected by tomato grey mold.After identification,it was determined as B.cinerea.The 18S rDNA and internal transcriptional spacer(ITS)sequences of strain nky007a were amplified for molecular identification and classification.[Result]The 18S rDNA sequence of the strain shared the homology of 99.95%with Botryotinia fuckeliana(EF 110887.1);the ITS rDNA sequence had the homology of 100%with Botryotinia fuckeliana(AB444949.1),and there was no difference in bases.Phylogenetic tree analysis of strain nky007a indicated that nky007a belonged to Botrytis.When healthy tomatoes were infected by the strain,the incidence rate of tomato grey mold was up to 95%,indicating the pathogenicity of the strain.[Conclusion]Morphological identification,molecular identification and pathogenicity analysis results show that the strain nky007a is a highly pathogenetic strain B.cinerea.展开更多
Twenty-six strains of Aspergillus fumigaius were screened for toxigenicity for fumitremorgins A and B. Twenty-three of 26 strains can produce fumitremorgin B in rice medium determined by TLC and HPLC, and no fumitremo...Twenty-six strains of Aspergillus fumigaius were screened for toxigenicity for fumitremorgins A and B. Twenty-three of 26 strains can produce fumitremorgin B in rice medium determined by TLC and HPLC, and no fumitremorgin A was detected. The strains of no.C4104 and no. 3656 were inoculated onto 5 kg of rice media and incubated in a modified procedure. Finally, 4.0 g of fumitremorgin B was obtained after extraction and purification by modified methods, and was confirmed by TLC, HPLC, spectral analysis together with other physicochemical analysis. This is the first report of the preparation of fumitremorgin B in China.展开更多
A facultative heterotrophic strain (DS-0205) was isolated from a deep-sea sediment sample collected at a depth of 5.2 km in the eastern Pacific Ocean,China. Strain DS-0205 is motile helmet-like single cell or pairs,fo...A facultative heterotrophic strain (DS-0205) was isolated from a deep-sea sediment sample collected at a depth of 5.2 km in the eastern Pacific Ocean,China. Strain DS-0205 is motile helmet-like single cell or pairs,forming hemisphere with the center sunken of variable size. It has a widespread carbon source and nitrogen source,including agarose,citric acid,salicin,D-glucitol nitrate,sodium nitrite and ethylamine. It can grow in the following environment:temperature 4-37 ℃,pH 2.0-12.0,tolerance to NaCl≤15%. Two phylogenetic trees,one based on the ITS and 5.8S rRNA sequences and the other based on the 18S rRNA sequences,unite strain DS-0205(=JCM 0205) to the type strain of Rhodosporidium diobovatum JCM 3787 through a considerable evolutionary distance. These results suggest that strain DS-0205 is a new strain of the Rhodosporidium diobovatum.展开更多
基金supported by the Natural Science Foundation of Hebei Province,China(C2013204115)the Science and Technology Support of Hebei Province,China(C20121124001)
文摘Large amounts ofFlaveria bidentis's root culturing solution were obtained by using DFT (deep flow technique) equipment and these solution which was vacuum concentrated (10, 20 mg mL-~) can have a certain inhibition on Triticum aestivum, Cucumis sativus, Raphanus sativus, Amaranthus retroflexus, Setaria viridis, Chenopodium album, Echinochloa crusgalli and Chloris virgata. This outcome suggested some active compounds in the root exudates ofFIaveria bidentis can inhibit the germination, seedling elongation and root length. The dichloromethane extract of root exudates was identificated by GC-MS, and 29 kinds of compounds, including esters, hydrocarbons, ketones, thiazole, amines, etc. were obtained and the phthalate n-octyl ester, phthalate 2-ethylhexyl ester were proved to be allelochemicals. The culturing solution of root exudates was separated through the resin column and silica gel column and a component inhibiting seedling height, root length and fresh weight of wheat was got. There were 6 kinds of organic compounds in this component including dioctyl phthalate, 1,2-phthalate, mono(2-ethylhexyl) ester by GC-MS.
基金Supported by National Key Basic Research Program of China(973 Program)(2017YFD0500605)
文摘[Objectives]This study aimed to investigate the pathogenicity,growth characteristics and drug resistance of Streptococcus suis type 2.[Methods]Bacterial isolation and identification,biochemical experiments,determination of growth curve and correlation curve between OD 600 values and viable counts,drug susceptibility tests,pathogenicity analysis,and histopathological observations were carried out.[Results]The Streptococcus strain isolated from infected pigs was identified as Streptococcus suis type 2,which was named TA01 strain.TA01 strain reached the growth peak at 6-8 h post-incubation,and viable counts gradually declined after 8 h of incubation.The correlation equation between OD 600 values and viable counts is y=24.659 x-1.076 1,R^2=0.996 7.TA01 strain was sensitive to penicillin,erythromycin,florfenicol and oxacillin,and resistant to ciprofloxacin,polymyxin B and clindamycin.According to the results of pathogenicity analysis,all the mice in 3.6×10^9 cfu/mouse group died within 48,and these dead mice exhibited acute pyaemia septica.Based on the Reed-Muench formula,it was calculated that LD 50 of TA01 strain was 1.137×10^8 cfu/mouse.Pathological examination showed obvious blue-stained bacteria clusters,accompanied by neutrophil infiltration.[Conclusions]TA01 strain was a virulent strain of Streptococcus suis type 2.Compared with Streptococcus strains which were isolated and reported in China,TA01 strain exhibited strong virulence and rapid proliferation.
基金supported by the funds from the National Natural Science Foundation of China (30760008)
文摘[ Objective] To screen suitable lactic acid bacterium strains from forage corn which can be used as silage additives. [ Method] The lactic acid bacterium strains were isolated by inoculation on MRS solid medium containing calcium carbonate, and they were preliminarily identified through morphological, physiological and biochemical experiments. The acid production efficiency was determined. Twelve strains having strong acid-pro- duction ability were selected, and their salt tolerance and acid tolerance were detected. The sequences of their 16 S rDNA were also analyzed. [ Result] A total of 44 lactic acid bacterium strains were isolated from the forage com. As evidenced by the physiological and biochemical experi- ments, the twelve strains having strong acid-production ability belonged to Leuconostoc, Lactobacillus and Enterococcus, respectively, and they had strong salt tolerance and acid tolerance. According to the sequences of 16 S rDNA, A4, B9, B11, B12 and B14 were Lactobacillus plantarum; A1, A2., A7, A11 and B8 were Leuconostoc mesenteroides dextran subspecies; and AB and A9 were Enterococcus hirae. [ Conclusion ] The lactic acid bacterium strains with strong acid-production ability isolated from forage corn can be developed into silage additives.
基金the National Natural Science Foundation of China (Grant No. 30671397)
文摘A survey on isolation and detection of the casual organism of bacterial grain rot of rice was conducted during 1997-2006. In 2006, six pathogenic bacterial strains were isolated from two symptomless seed samples of rice (Oryza sativa L.) originally produced in Hainan Province and then planted in Zhejiang Province, China. They were identified as Burkholderia glumae which is the causal organism of bacterial grain rot of rice by physiological characteristics, colony morphology, pathogenicity test, Biolog, fatty acid methyl ester (FAME) analysis and RAPD-PCR compared with the four standard reference strains. It is confirmed that there is the infection of B. glumae in so-called 'health looking seeds'.
文摘Five strains of alginate-degrading bacteria Were isolated from the decaying parts of Laminria japonicaand Undaria pinnatifida and identified as Alteromonas espejiana (Strain A101, A102, A103, A105 ) and Alteromonas macleodii(Strain A104). When incubated at 25 t for 144 h in the liquid mediuxn which contamed 0. 5%peptone, 0. 3% -0. 6%sodium alginate, 0. 1 % yeast extract, 3% NaCI, pH 7. 5, the stain A102 pnduced the highest amount of alginase.
基金the National Natural Science Foundation of China(31171877)
文摘In order to understand the composition and structure of herbicidal active substance from the root of Flaveria bidentis (L.) Kuntze, the isolation and structural identification were researched in this paper. The crude extract from the root ofF. bidentis (L.) Kuntze was extracted by petroleum ether, ethyl acetate, and water saturation of n-butyl alcohol, respectively, and the extraction fluid was separated by using the method of TLC, then the main fraction was separated by HPLC, and the structure of the herbicidal active substance was analyzed by LC-MS, elemental analysis and ~H-NMR. The results showed that the petroleum extraction had the strongest herbicidal activity, and the purple blue stripe separated by TLC had the strongest effect on Digitaria sanguinalis. The herbicidal active substance was identified as ct-terthienyl according to the data of LC-MS, elemental analysis and 1H-NMR.
基金funded by the Technology Development Program of Chengyang District of Qingdao City (2008-4-sf)
文摘[ Objective] The aim of this study was to determine and analyze the pathogen and the reasons of duck viral hepatitis which is prevalent recently and difficult to control. [Method] Viruses were isolated from livers and spleens of ducks with typical clinical symptoms in Linyi, Weifang, Binzhou and other regions of Shandong Province. The pathogenic characteristics were observed by inoculation in chicken or duck embryo, RT- PCR, serological test, and duck regression. [ Result] Four duck hepatitis virus (DHV) strains were isolated, and the 5th passage allantoic fluid contained 10^3.41 -10^5.20 ELD50/mI. The serum cross protection rate was 20% -80% between the DHV stains and DHV type I. The mortalities of 4- day-old healthy ducks challenged by these four stains were 50% -100%. All challenged ducks had typical lesions of duck viral hepatitis, and the death peak appeared after 24-48 h. [Conclusion] The virulence of different DHV isolates has regional difference.
基金Supported by Natural Science Foundation of Jiangsu Province(BK20151283)Science Program of Lianyungang(CG1612)+1 种基金521 Talent Project of LianyungangJiangsu Provincial Practice Innovation Training Program for Undergraduate
文摘In this study, bioassay-guided isolation, identification and biological evaluation of antioxidant components from total flavonoids of Chinese herbal plant Mimenghua were performed. 1, 1-Diphenyl-2-picrylhydrazyl(DPPH) radical scavenging test was adopted as the bioassay-guided method, Sephadex LH-20 column chromatography and high performance liquid chromatography were used as the purification tools for the acquisition of antioxidant components. One compound was obtained and identified as acteoside by its physicochemical properties and spectral characteristics. Antioxidant activity in vitro of acteoside was determined by evaluation of the scavenging activity on DPPH radical and hydroxyl radical, reducing power and total antioxidant capability.The results showed that acteoside had significant antioxidative activity and possessed higher activity with the increase of concentration, which provides the potential application of acteoside in food, pharmaceutical and cosmetic industries.
基金Supported by Incentive Subsidy Program of Hebei Department of Science and Technology(15926620H)Key Technology R&D Program of Qinhuangdao Science and Technology Bureau(201401A067)+1 种基金Prevention and Control of Major Bacterial Diseases in Industrial Farming Fishes(201602A341)Sereening and Preliminary Application of Protective Antigen of Two Important Marine Pathogens(2018HY007)
文摘In May 2016,an epizootic occured among cultured tongue soles caused mass deaths in a fish farm in Qinhuangdao,China.In order to find out the etiological agent,a bacterial strain was isolated from ascites and other tissues of sick tongue sole aseptically collected.The isolate was identified as Photobacterium damselae subsp.damsela(PDD) by isolation culture,Gram staining,physiological identification,morohological observation,biochemical identification and 16S rDNA sequence analysis.The results showed that the isolate shared 99.6% homology with the reference strain in GenBank.The animal regression test displayed that the isolate had very strong pathogenicity to tongue sole.The LD(50) was 3.1 × 10~4 CFU/mL,and it showed pathogenicity to mammals.The antimicrobial susceptibility test showed the isolate was highly sensitive to nrofloxacin,Norfloxacin,Ciprofloxacin,Mequindox;moderately sensitive to Cefradine,Doxycycline;and insensitive to Gentamicin,Ceftriaxone,Tilmicosin,etc..
文摘Objective\ To understand the transcription of BamHI L DNA fragment from genome of strong virulent GA strain of Marek′s disease herpesvirus (MDV) in lymphoblastoid tumor tissue induced by oncogenic strain Beijing 1 (a specific local strain in China) of MDV. Methods\ Two oligonucleotide primers were synthesized according to the reported sequence of \%meq\% gene an ideal oncogenic candidate and our previously determined sequence of BamHI L fragment of Marek′s disease herpesvirus (MDV), respectively. Reverse transcriptase PCR(RT PCR) assay was performed by using these primers and the mRNA as a template which was isolated from visceral lymphoblastoid tumors obtained from chickens artificially infected with strain Beijing 1 of oncogenic MDV. Southern blot molecular hybridization was further carried out to detect the product of RT PCR with digoxigenin labeled nucleotide probe from BamHI I2 and L fragment in the gene library of MDV strain GA, respectively. Results\ Two probes could simultaneously hybridize this cDNA amplified by RT PCR with a length of about 730 bp. Conclusion\ It is suggested that \%meq\% transcription could extend from the right hand end of BamHI I2 to the adjacent BamHI L, and the BamHI L region was likely to be transcribed in MDV induced lymphoblastoid tumors.
文摘Flavotoxin A was isolated from Pseudomonas cocovenenans subsp. farinofermentans culture in semisolid potato-dextrose-agar medium, which was isolated from fermented corn meal that had caused food poisoning outbreaks in China. The isolation, purification, and chemical structure of this toxin were studied. The NMR spectra, the uv spectra, and molar extinction coefficients, and the mass spectra of Flavotoxin A are in good agreement with those reported for bongkrekic acid. Therefore, Flavotoxin A and bongkrekic acid are the same organic chemical compound; the molecular formula is C_(28)H_(38)O_7. The oral LD_(50) of the purified Flavotoxin A in mice was 3.16mg/kg (1.53-6.15mg/kg). The existence of bongkrekic acid in toxic fermented corn samples collected during food poisoning outbreaks was also confirmed. It is concluded that bongkrekic acid has played an important role in the outbreaks of fermented corn poisoning. 1989 Academic Press, Inc.
基金Supported by Natural Science Foundation of China(31270674)Innovative High School Key Research Platform of Zhaoqing University(CQ201607)
文摘In the introduction and propagation of red sandalwood (Pterocarpus santalinus), a serious leaf disease of its seedlings in winter and spring seasons was found, but the name of the disease and its pathogen species have not been reported. The pathogen isolated from infected leaves of 18-month-old seedlings was identi- fied as Colletotrichum gloeosporioides by morphological characteristics of colony and conidium, and analysis results of rDNA-intemal transcribed spacer sequence (ITS) of the strain. Pathogenicity test results further confirmed that C. gloeosporioides was the pathogen responsible for the infected leaves symptoms of red sandal- wood. However, the disease belongs to an atypical anthraenose. Control of the leaf diseases of red sandalwood seedlings was discussed.
基金Supported by the Science and Technology Innovative Research Team of Anhui Academy of Agricultural Sciences(14C0504)the Youth Innovation Foundation of President of Anhui Academy of Agricultural Sciences(14B0529)Anhui Aquaculture Industry Technology System for Shrimp and Crab
文摘This experiment was conducted to clarify species and drug resistance of pathogen from the diseased Procambarus clarkia. Pathogenic bacteria from hepatopancreas of the diseased P. clarkia were examined using conventional methods,and then were isolated. The further tests and analysis of the isolated strain were developed,including the regression experiment to P. clarkia,the morphology,physiological and biochemical characteristics,sequence analysis of their 16 S rRNA and gyr B genes,and the susceptibility test to antibiotics. Large colonies with similar morphology and color were obtained. Strain X120523 was identified as Citrobacter freundii,proved to have strong pathogenicity,and was susceptible to quinolones and aminoglycosides.
基金The project supported by National Natural Science Foundation of China
文摘The neuroexcitotoxic nonprotein amino acid β-N-oxalo-L-α, β-diaminopropionic acid (β-N-ODAP)and its isomer a-N-oxalo-L-α, β-diaminopropionic acid (α-N-ODAP)in Panax ginseng C. A. Meyer(cultivated ih Northeastern China), Panax quinquefolius L., Panax notoginseng F.H. Chen (cultivated in Southwestern China), Korean red ginseng and Jilin red ginseng were isolated and identified. Efficient separation and purification methods for β-N-ODAP and α-N-ODAP were developed.
基金Supported by Youth Fund of Jiangsu Agri-animal Husbandry Vocational College(NSFQN1304)Key Project of Jiangsu Agri-animal Husbandry Vocational College(ZD201104)Phoenix Talent Project of Jiangsu Agri-animal Husbandry Vocational College(10434014001)
文摘In this study, the liver, kidney and spleen tissues were collected from pigs with suspected PR in a pig farm in Jiangyan District, Taizhou City for virus isolation and identification. The isolated virus was inoculated onto PK15 monolayer cells. The virus culture was collected to extract genomic DNA for PCR assay and indirect immunoinfluscent assay. The results showed that the isolated virus was porcine pseudorabies virus, which was named TAIZ130417. The growth titer of the isolated virus reached 10 8.12 TCID 50 /ml on PK15 cells. Rabbits inoculated with the isolated virus soon exhibited pseudorabies symptoms such as itching and eventually died. The results provided reference for in-depth research and scientific prevention and control of pseudorabies.
文摘Pasteurella species is considered the principal pathogen of the respiratory tract.Mannheimia haemolytica and Pasteurella multocida were investigated and typed from nasal swabs and tissues taken from sheep,goat and cattle.Indeed,41 lung and 121 nasal swabs samples were collected from animals with respiratory diseases during 2015 to 2017 in six different regions in Morocco.At first,a screening of Pasteurella species using the real time PCR(RT-PCR)was carried out,then all isolated strains on agar blood were confirmed by PCR gel based assay specific for M.haemolytica and P.multocida.Pathogenicity was evaluated in mice and histopathological examination was done on some of lung tissue.The results revealed that 34 samples of which 28(55%)from nasal swabs and six(38%)from lungs were positive for M.haemolytica and nine samples of which seven(14%)from nasal swabs and two(13%)from lungs were positive on P.multocida serogroup A.Seventy-two percent(72%)isolates were highly pathogenic to mice,which is in accordance with the results obtained by histopathology examination.This is the first report for widespread infections of Pasteurella(M.haemolytica&P.multocida)in ruminants in Morocco.Therefore,measures including development of vaccines are highly required to mitigate the impact of the bacteria in animals.
文摘To identify the member of the caspase family proteases involved in γ radiation induced apoptosis in HL 60 cells, using degenerated oligonucleotide primers encoding the highly conserved peptides, which were present in all known caspases, RT PCR was performed on poly (A) RNA from the γ radiation induced apoptotic HL 60 cells. Then, cloned and sequenced to identify the amplified DNA fragments. The results showed that the amplified DNA fragments were identified with a part of caspase 3 cDNA. It indicated that caspase 3 was involved in γ radiation induced apoptosis in HL 60 cells and may be the pivotal element of radiation induced apoptosis.
基金Science and Technology Guidance Program of Xinjiang Academy of Agricultural Reclamation Sciences(2020YJ019).
文摘[Objective]The paper was to isolate and identify Botrytis cinerea from processing tomato.[Method]The strain nky007a was isolated and purified from fruits infected by tomato grey mold.After identification,it was determined as B.cinerea.The 18S rDNA and internal transcriptional spacer(ITS)sequences of strain nky007a were amplified for molecular identification and classification.[Result]The 18S rDNA sequence of the strain shared the homology of 99.95%with Botryotinia fuckeliana(EF 110887.1);the ITS rDNA sequence had the homology of 100%with Botryotinia fuckeliana(AB444949.1),and there was no difference in bases.Phylogenetic tree analysis of strain nky007a indicated that nky007a belonged to Botrytis.When healthy tomatoes were infected by the strain,the incidence rate of tomato grey mold was up to 95%,indicating the pathogenicity of the strain.[Conclusion]Morphological identification,molecular identification and pathogenicity analysis results show that the strain nky007a is a highly pathogenetic strain B.cinerea.
文摘Twenty-six strains of Aspergillus fumigaius were screened for toxigenicity for fumitremorgins A and B. Twenty-three of 26 strains can produce fumitremorgin B in rice medium determined by TLC and HPLC, and no fumitremorgin A was detected. The strains of no.C4104 and no. 3656 were inoculated onto 5 kg of rice media and incubated in a modified procedure. Finally, 4.0 g of fumitremorgin B was obtained after extraction and purification by modified methods, and was confirmed by TLC, HPLC, spectral analysis together with other physicochemical analysis. This is the first report of the preparation of fumitremorgin B in China.
基金Projects(40776035, 40376036) supported by the National Natural Science Foundation of ChinaProject(DY105-02-04-05) supported by the China Ocean Mineral Resources Research and Development Association+2 种基金Project(07MX27) supported by the Mittal Student FoundationProject (2340-74236000003) supported by the Post-graduate Foundation of Hunan Province, ChinaProject (200805330053) supported by the Doctoral Foundation of Ministry of Education of China
文摘A facultative heterotrophic strain (DS-0205) was isolated from a deep-sea sediment sample collected at a depth of 5.2 km in the eastern Pacific Ocean,China. Strain DS-0205 is motile helmet-like single cell or pairs,forming hemisphere with the center sunken of variable size. It has a widespread carbon source and nitrogen source,including agarose,citric acid,salicin,D-glucitol nitrate,sodium nitrite and ethylamine. It can grow in the following environment:temperature 4-37 ℃,pH 2.0-12.0,tolerance to NaCl≤15%. Two phylogenetic trees,one based on the ITS and 5.8S rRNA sequences and the other based on the 18S rRNA sequences,unite strain DS-0205(=JCM 0205) to the type strain of Rhodosporidium diobovatum JCM 3787 through a considerable evolutionary distance. These results suggest that strain DS-0205 is a new strain of the Rhodosporidium diobovatum.