海绵共附生放线菌筛选与抑制海水养殖病原弧菌研究

发布时间：2018-05-22 14:25

  本文选题：海绵共附生放线菌 + 抑菌活性　； 参考：《大连海洋大学》2017年硕士论文

【摘要】：本文以研究海绵共附生放线菌次级代谢产物对海水养殖病原弧菌的抑菌活性为主要目的,从肾指海绵(Reniochalina sp.),山海绵(Mycale sp.)和居蟹皮海绵(Suberites domuncula)中分离培养出27株共附生放线菌,与实验室前期保存的海绵放线菌去重后共59株,16S r DNA序列比对初步鉴定均为链霉菌属(Streptomyces)放线菌。以副溶血弧菌(Vibrio parahaemolyticus)、哈维弧菌(Vibrio harveyi)、鳗弧菌(Vibrio anguillarum)、灿烂弧菌(Vibro Splendidus)4株革兰氏阴性菌和海豚链球菌(Streptococcus iniae)、马胃葡萄球菌(Staphylococcus equorum)2株革兰氏阳性菌为指示菌,对59株放线菌的抑菌活性进行反复筛选,筛选出11株抑菌活性较强且具有广谱性的放线菌,并确定海绵放线菌FH作为研究的目标菌株。以副溶血弧菌、哈维弧菌为指示菌,对FH菌株的抑菌活性研究如下:对海绵放线菌FH的16S r DNA序列进行测序分析,初步鉴定为球孢链霉菌(Streptomyces globisporus)。以抑菌活性为导向对FH菌株的发酵条件进行了优化,优化结果为温度25℃,p H值7.5,装液量30 m L/250 m L,发酵时间120 h。FH菌株特征研究显示,FH发酵液粗提物相当于庆大霉素标准液的效价为387.27 mg/L,在4℃和-20℃低温条件下保存2个月对各指示菌的抑菌活性稳定。在灭菌海水中,添加FH菌株发酵产物的实验组,初始密度103个/m L的副溶血弧菌和哈维弧菌均得到了有效抑制甚至杀死;添加FH菌丝体的实验组中,初始密度103个/m L的副溶血弧菌和初始密度102个/m L的哈维弧菌得到了有效抑制。在海参育苗中,FH菌丝体在弧菌病害预防中则表现出较好的结果,作为生物防治具有可行性。而FH发酵产物和发酵液粗提物不适合直接添加到养殖海水中作为预防或治疗的手段。上述海绵放线菌FH及其发酵产物的抑菌活性研究,说明了海绵放线菌在天然活性产物开发上具有重要潜力,在海水养殖病害防治领域具有广阔的应用前景。
[Abstract]:The aim of this paper is to study the antibacterial activity of secondary metabolites of actinomycetes sp.against pathogenic Vibrio vibrio in mariculture, from Reniochalina sp. of Reniochalina sp., Mycale sp. A total of 27 coepiphytic actinomycetes were isolated from Suberites domuncula and compared with 59 strains of actinomyces sponges stored in laboratory after being removed and identified as Streptomyces actinomycetes. Vibrio parahaemolyticus, Vibrio harveyii, Vibrio anguillarum, Vibrio Splendidus)4, Streptococcus iniaeae, Staphylococcus equorum)2, Gram-positive bacteria, The antimicrobial activity of 59 actinomycetes was screened repeatedly, 11 actinomycetes with strong antibacterial activity and broad spectrum were screened out, and the spongy actinomycetes FH was selected as the target strain. The antibacterial activity of Vibrio parahaemolyticus and Vibrio Harvey against FH strain was studied as follows: the 16s r DNA sequence of actinomyces sponges FH was sequenced and identified as Streptomyces globisporusus. The fermentation conditions of FH strain were optimized based on bacteriostatic activity. The optimized results were as follows: temperature 25 鈩，

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