Although Vibrio parahaemolyticus has become the most common pathogen in fresh and frozen seafood,its virulence changes have often been ignored during the processing of seafood.To investigate these potential risks,we u...Although Vibrio parahaemolyticus has become the most common pathogen in fresh and frozen seafood,its virulence changes have often been ignored during the processing of seafood.To investigate these potential risks,we used frozen Penaeus chinensis as examples,and the most virulent factors of V.parahaemolyticus,including amounts,viable but nonculturable(VBNC)status,toxins TDH and TRH,and virulence genes tdh and trh,were determined.Bacterial quantities were signifi cantly reduced during drain and sprinkling phases,but caused by different factors.By SYTO9 and PI staining showed that washing was the main reason for the bacterial reduction at the drain phase,while the strain entering VBNC state was another reason at sprinkling phase.Their hemolysis toxicity,produced by TDH and TRH,became stronger after inoculation on shrimp,and could be detected throughout the process.Moreover,tdh and trh also exhibited trends similar to that of the hemolysis toxicity test.tdh was almost to a two-fold expression level during ice-glazing phase,while trh only express at a low level,less than half of the expression level before inoculation.These results demonstrated that the strains were not dead during freezing process,but became VBNC cells,which still produced and accumulated toxins,especially TDH,the most virulent factor.展开更多
[Objective] This study aimed to analyze the in vitro inhibitory activity of Shisandra chinensis and Polygonatum sibiricum against Vibrio harveyi and its biofilms. [Result] By agar diffusion test, in vit...[Objective] This study aimed to analyze the in vitro inhibitory activity of Shisandra chinensis and Polygonatum sibiricum against Vibrio harveyi and its biofilms. [Result] By agar diffusion test, in vitro inhibitory activity of 5. chinensis and P. sibiricum against V. harveyi was investigated. The minimal inhibitory concentration ( MIC) and minimal bactericidal concentration (MBC) of 5. chinensis and P. sibiricum against V. harveyi were determined by doubling dilution meth-od. The inhibitory activity of 5. chinensis and P. sibiricum on the formation of V. harveyi biofilms was evaluated by modified MTT assay. [ Result ] Both 5. chinen-sis and P. sibiricum had inhibitory activity against V. harveyi. The inhibition zone diameter of 5. chinensis against V. harveyi was 17. 95 mm; MIC and MBC of 5. chinensis were both 3.125 mg/ml. The inhibition zone diameter of P. sibiricum against V. harveyi was 12. 22 mm; MIC and MBC of P. sibiricum were 3.125 and 6.250 mg/ml, respectively. When the concentration was higher than 6. 25 mg/ml, 5. chinensis decoction had extremely significant inhibitory activity against V. harveyi (P 〈 0. 01) ; when the concentration was higher than 3. 125 mg/ml, P. sibiricum had extremely significant inhibitory activity against V. harveyi (P 〈0. 01). [ Conclusion] 5. chinensis and P. sibiricum could significantly inhibit V. harveyi and its biofilms.展开更多
[Objective] This study was conducted to determine the in-vitro inhibitory effects of Prunus mume,Coptis chinensis and Crataegus pinnatifida on Vibrio harveyi and its biofilm. [Method]The inhibitory zone diameters of t...[Objective] This study was conducted to determine the in-vitro inhibitory effects of Prunus mume,Coptis chinensis and Crataegus pinnatifida on Vibrio harveyi and its biofilm. [Method]The inhibitory zone diameters of the three Chinese herbal medicines against V. harveyi were determined by agar diffusion method; the minimal inhibitory concentration( MIC) and minimal bactericidal concentration( MBC) values of the three Chinese herbal medicines against V. harveyi were determined by doubling dilution method; and the effects of the three Chinese herbal medicines on the formation of V. harveyi biofilm were determined by methyl thiazolyl tetrazolium( MTT) method. [Result]The three Chinese herbal medicines all inhibited V. harveyi to different degrees. C. chinensis and C. pinnatifida and P. mume exhibited the inhibitory zone diameters of( 17. 62 ± 0. 04),( 20. 16 ± 0. 08) and( 30. 76 ± 0. 26) mm against V. harveyi,respectively. P. mume and C. pinnatifida had strong inhibitory effects on V. harveyi. The MIC and MBC values of P. mume against V. harveyi were 7. 812 5 mg/ml; the MIC and MBC values of C. pinnatifida against V. harveyi were 31. 25 mg/ml; and the MIC and MBC values of C. chinensis against V. harveyi were 62. 5 mg/ml. P. mume had the strongest antibacterial and bactericidal ability. The MIC values of C. pinnatifida,C. chinensis and P. mume against V. harveyi were 7. 81,7. 81 and 1. 96 mg/ml,respectively,i. e.,P. mume exhibited the lowest MIC. [Conclusion] P. mume,C. pinnatifida and C. chinensis all have inhibitory effects on V. harveyi and its biofilm,and P. mume has the strongest bactericidal ability.展开更多
基金funded by grants from the National Key Research and Development Program of China[2018YFC1602201]Key Research and Development Program of Shaanxi Province[2021NY-158]+1 种基金the National Natural Science Foundation of China[31671780]the Agricultural Product Quality and Safety Risk Assessment Foundation of the Ministry of Agriculture and Rural Affairs of the People’s Republic of China[GJFP2020002,GJFP2020003].
文摘Although Vibrio parahaemolyticus has become the most common pathogen in fresh and frozen seafood,its virulence changes have often been ignored during the processing of seafood.To investigate these potential risks,we used frozen Penaeus chinensis as examples,and the most virulent factors of V.parahaemolyticus,including amounts,viable but nonculturable(VBNC)status,toxins TDH and TRH,and virulence genes tdh and trh,were determined.Bacterial quantities were signifi cantly reduced during drain and sprinkling phases,but caused by different factors.By SYTO9 and PI staining showed that washing was the main reason for the bacterial reduction at the drain phase,while the strain entering VBNC state was another reason at sprinkling phase.Their hemolysis toxicity,produced by TDH and TRH,became stronger after inoculation on shrimp,and could be detected throughout the process.Moreover,tdh and trh also exhibited trends similar to that of the hemolysis toxicity test.tdh was almost to a two-fold expression level during ice-glazing phase,while trh only express at a low level,less than half of the expression level before inoculation.These results demonstrated that the strains were not dead during freezing process,but became VBNC cells,which still produced and accumulated toxins,especially TDH,the most virulent factor.
基金Supported by Project of Enhancing School with Innovation of Guangdong Ocean University(GDOU2015050216)Major Program for the Fundamental Research of the Department of Education of Guangdong Province(2014GKXM046)International Cooperation Innovation Platform Project of Universities in Guangdong Province(2013gjhz0008)
文摘[Objective] This study aimed to analyze the in vitro inhibitory activity of Shisandra chinensis and Polygonatum sibiricum against Vibrio harveyi and its biofilms. [Result] By agar diffusion test, in vitro inhibitory activity of 5. chinensis and P. sibiricum against V. harveyi was investigated. The minimal inhibitory concentration ( MIC) and minimal bactericidal concentration (MBC) of 5. chinensis and P. sibiricum against V. harveyi were determined by doubling dilution meth-od. The inhibitory activity of 5. chinensis and P. sibiricum on the formation of V. harveyi biofilms was evaluated by modified MTT assay. [ Result ] Both 5. chinen-sis and P. sibiricum had inhibitory activity against V. harveyi. The inhibition zone diameter of 5. chinensis against V. harveyi was 17. 95 mm; MIC and MBC of 5. chinensis were both 3.125 mg/ml. The inhibition zone diameter of P. sibiricum against V. harveyi was 12. 22 mm; MIC and MBC of P. sibiricum were 3.125 and 6.250 mg/ml, respectively. When the concentration was higher than 6. 25 mg/ml, 5. chinensis decoction had extremely significant inhibitory activity against V. harveyi (P 〈 0. 01) ; when the concentration was higher than 3. 125 mg/ml, P. sibiricum had extremely significant inhibitory activity against V. harveyi (P 〈0. 01). [ Conclusion] 5. chinensis and P. sibiricum could significantly inhibit V. harveyi and its biofilms.
基金Supported by the Higher Educational Cultivation Program for Major Scientific Research Projects of Guangdong Ocean University(GDOU2015050216)Outstanding Young Backbone Teacher Cultivation Program of Guangdong Ocean University(HDYQ2015005)+1 种基金Natural Science Foundation of Guangdong Province(2017A030313174)Guangdong Provincial Science and Technology Planning Project(2014A020208117 and 2015A020209163)
文摘[Objective] This study was conducted to determine the in-vitro inhibitory effects of Prunus mume,Coptis chinensis and Crataegus pinnatifida on Vibrio harveyi and its biofilm. [Method]The inhibitory zone diameters of the three Chinese herbal medicines against V. harveyi were determined by agar diffusion method; the minimal inhibitory concentration( MIC) and minimal bactericidal concentration( MBC) values of the three Chinese herbal medicines against V. harveyi were determined by doubling dilution method; and the effects of the three Chinese herbal medicines on the formation of V. harveyi biofilm were determined by methyl thiazolyl tetrazolium( MTT) method. [Result]The three Chinese herbal medicines all inhibited V. harveyi to different degrees. C. chinensis and C. pinnatifida and P. mume exhibited the inhibitory zone diameters of( 17. 62 ± 0. 04),( 20. 16 ± 0. 08) and( 30. 76 ± 0. 26) mm against V. harveyi,respectively. P. mume and C. pinnatifida had strong inhibitory effects on V. harveyi. The MIC and MBC values of P. mume against V. harveyi were 7. 812 5 mg/ml; the MIC and MBC values of C. pinnatifida against V. harveyi were 31. 25 mg/ml; and the MIC and MBC values of C. chinensis against V. harveyi were 62. 5 mg/ml. P. mume had the strongest antibacterial and bactericidal ability. The MIC values of C. pinnatifida,C. chinensis and P. mume against V. harveyi were 7. 81,7. 81 and 1. 96 mg/ml,respectively,i. e.,P. mume exhibited the lowest MIC. [Conclusion] P. mume,C. pinnatifida and C. chinensis all have inhibitory effects on V. harveyi and its biofilm,and P. mume has the strongest bactericidal ability.