为研究放线菌对海水养殖病原弧菌(哈维弧菌Vibrio harveyi和灿烂弧菌Vibrio splendidus)的抑制效果,从繁茂膜海绵Hymeniacidon perlevis中分离筛选出了一株具有抑菌活性的放线菌(FH),并采用16S r DNA基因序列进行分析,初步鉴定为球孢链...为研究放线菌对海水养殖病原弧菌(哈维弧菌Vibrio harveyi和灿烂弧菌Vibrio splendidus)的抑制效果,从繁茂膜海绵Hymeniacidon perlevis中分离筛选出了一株具有抑菌活性的放线菌(FH),并采用16S r DNA基因序列进行分析,初步鉴定为球孢链霉菌Streptomyces globisporus;以抑菌活性为导向对放线菌FH菌株的发酵条件进行优化,并通过测量发酵沉淀菌丝体干质量,获得了FH菌株生长曲线,同时研究了发酵产物保存温度及时间对抑菌效果的影响,以及FH发酵产物在灭菌海水中对弧菌的抑制作用。结果表明:对FH菌株生长曲线测定结果显示,0~15 h为适应期,15~72 h为指数生长期,72~120 h为稳定期,120 h后为衰亡期;抑制弧菌效果试验显示,FH菌株发酵正交试验的最优条件为温度25℃、p H 7.5、装液量30m L(250 m L三角瓶);在正交试验最优条件下,FH菌株发酵培养72 h获得的粗提物抑制哈维弧菌和灿烂弧菌的效果最好;FH菌株发酵粗提物在4℃和-20℃下保存60 d和在室温保存7 d,其抑菌效果无显著性差异(P>0.05);在100 m L灭菌海水中,FH菌株发酵产物2 m L可有效抑制哈维弧菌和灿烂弧菌的繁殖。研究表明,海绵放线菌及其发酵产物在海水养殖领域具有潜在应用价值。展开更多
Objective:To isolate novel actinomycetes and to evaluate their antibacterial activity.Methods:Three soil samples were collected from Vengodu(village)in Kanchipuram district,Tamil Nadu,India.Actinomycetes were isolated...Objective:To isolate novel actinomycetes and to evaluate their antibacterial activity.Methods:Three soil samples were collected from Vengodu(village)in Kanchipuram district,Tamil Nadu,India.Actinomycetes were isolated using serial dilution and plating method on actinomycetes isolation agar.Results:Totally 35 isolates were obtained on the basis of colony characteristics on actinomycetes isolation agar.All the isolates were screened for antibacterial activity by cross streak method.Medium and optimization of day were done for the potent strains using Nathan's agar well diffusion method.Isolation of bioactive compounds from significant active isolates was done by using different media.The most active isolate VAS 10 was identified as Actinobacterium Loyola PBT VAS 10(accession No.JF501398)using 16s rRNA sequence method.The hexane,ethyl acetate,dichloromethane and butanol extracts of VAS 10 were tested against bacteria.The maximum antibacterial activity was observed in dichloromethane and ethyl acetate;maximum zones of inhibition were observed against Enterococcus durans.The rRNA secondary structure and the restriction sites of Actinobacterium Loyola VAS 10 were predicted using Genebee and NEBCutter online tools respectively.Conclusions:The present study showed that among the isolated actinomycetes,Actinobacterium Loyola PBT VAS 10(accession No.JF501398)showed good antibacterial activity against the tested bacteria.展开更多
文摘为研究放线菌对海水养殖病原弧菌(哈维弧菌Vibrio harveyi和灿烂弧菌Vibrio splendidus)的抑制效果,从繁茂膜海绵Hymeniacidon perlevis中分离筛选出了一株具有抑菌活性的放线菌(FH),并采用16S r DNA基因序列进行分析,初步鉴定为球孢链霉菌Streptomyces globisporus;以抑菌活性为导向对放线菌FH菌株的发酵条件进行优化,并通过测量发酵沉淀菌丝体干质量,获得了FH菌株生长曲线,同时研究了发酵产物保存温度及时间对抑菌效果的影响,以及FH发酵产物在灭菌海水中对弧菌的抑制作用。结果表明:对FH菌株生长曲线测定结果显示,0~15 h为适应期,15~72 h为指数生长期,72~120 h为稳定期,120 h后为衰亡期;抑制弧菌效果试验显示,FH菌株发酵正交试验的最优条件为温度25℃、p H 7.5、装液量30m L(250 m L三角瓶);在正交试验最优条件下,FH菌株发酵培养72 h获得的粗提物抑制哈维弧菌和灿烂弧菌的效果最好;FH菌株发酵粗提物在4℃和-20℃下保存60 d和在室温保存7 d,其抑菌效果无显著性差异(P>0.05);在100 m L灭菌海水中,FH菌株发酵产物2 m L可有效抑制哈维弧菌和灿烂弧菌的繁殖。研究表明,海绵放线菌及其发酵产物在海水养殖领域具有潜在应用价值。
基金Supported by Entomology Research Institute.Loyola College,Chennai Grant No.ER1/03/2011)
文摘Objective:To isolate novel actinomycetes and to evaluate their antibacterial activity.Methods:Three soil samples were collected from Vengodu(village)in Kanchipuram district,Tamil Nadu,India.Actinomycetes were isolated using serial dilution and plating method on actinomycetes isolation agar.Results:Totally 35 isolates were obtained on the basis of colony characteristics on actinomycetes isolation agar.All the isolates were screened for antibacterial activity by cross streak method.Medium and optimization of day were done for the potent strains using Nathan's agar well diffusion method.Isolation of bioactive compounds from significant active isolates was done by using different media.The most active isolate VAS 10 was identified as Actinobacterium Loyola PBT VAS 10(accession No.JF501398)using 16s rRNA sequence method.The hexane,ethyl acetate,dichloromethane and butanol extracts of VAS 10 were tested against bacteria.The maximum antibacterial activity was observed in dichloromethane and ethyl acetate;maximum zones of inhibition were observed against Enterococcus durans.The rRNA secondary structure and the restriction sites of Actinobacterium Loyola VAS 10 were predicted using Genebee and NEBCutter online tools respectively.Conclusions:The present study showed that among the isolated actinomycetes,Actinobacterium Loyola PBT VAS 10(accession No.JF501398)showed good antibacterial activity against the tested bacteria.
