产胞外多糖的海洋动物共附生细菌的分离及生物学活性分析  

Isolation of exopolysaccharide producing bacteria from marine symbiotic and epiphytic microorganisms and its biological activity analysis

作　　者：项燕华 覃美玲 李宜海 何秀苗 XIANG Yan-hua;QIN Mei-ling;LI Yi-hai;HE Xiu-miao(College of Marine and Biotechnology,Guangxi Minzu University/Guangxi Key Laboratory of Polysaccharide Materials and Modification,Nanning 530006,China)

机构地区：[1]广西民族大学海洋与生物技术学院/广西多糖材料与改性重点实验室,南宁530006

出　　处：《西南农业学报》2023年第9期2051-2058,共8页Southwest China Journal of Agricultural Sciences

基　　金：国家自然科学基金项目(32160824);广西自然科学基金项目(2017GXNSFAA198033);广西民族大学引进人才科研启动项目(2017KJQD005)。

摘　　要：【目的】对广西北部湾近海海域内部分鱼类、虾类和蟹类的体内和体表产胞外多糖(EPS)细菌进行分离及生物学活性分析,为该海域近海海洋动物共附生微生物资源的开发利用提供参考依据。【方法】以广西北部湾近海海域内采集到的部分鱼类、虾类和蟹类体内和体表共附生海洋细菌为研究对象,用黏液比色法进行初筛后,再用醇沉法和Sevage法提取、纯化细菌所产EPS,用苯酚硫酸法测定多糖含量,筛选出产EPS的海洋共附生细菌,通过16S rDNA序列对细菌种属进行鉴定和多样性分析,并通过1,1⁃二苯基⁃2⁃三硝基苯肼(DPPH)自由基的清除率及对鸡传染性法氏囊病病毒(IBDV)的抗病毒能力初步评估代表菌株的EPS生物学活性。【结果】共分离到37株产EPS的共附生海洋细菌,基于代表菌株的16S rDNA序列分析,菌株分别属于3纲4目6科6属10种,其中优势菌是芽孢杆菌属,占代表菌株42.86%,其次是普罗威登斯菌属(25.00%)和弧菌属(21.43%);EPS含量测定结果显示不同菌株之间产糖量具有明显差异;DPPH清除率测定结果显示,代表菌株所产的EPS均具有一定抗氧化活性,且不同属菌株之间、同属不同种菌株之间DPPH清除率差异明显;优势芽孢杆菌的代表菌株所产EPS具有抑制IBDV在鸡胚上复制的能力。【结论】广西北部湾近海海域内的海洋动物共附生微生物中产EPS细菌存在种属多样性,所产EPS具有抗氧化活性和抗病毒活性。研究结果能为广西北部湾近海海洋动物共附生细菌资源利用提供科学依据。【Objective】Extracellular polysaccharide(EPS)producing bacteria in vivo and on body surface of some fish,shrimp and crabs in the offshore waters of Beibu Gulf of Guangxi were isolated and their biological activities were analyzed to provide a scientific basis for develo⁃ping symbiotic and epiphytic microorganisms of marine animals in the coastal waters of Beibu Gulf of Guangxi.【Method】The marine bacteria were isolated from the intestinal and surface of a variety of fishes,shrimps and crabs in the area,and the EPS producing strains were screened by the mucous colorimetry.The EPS was extracted and purified by ethanol precipitation method and Sevage method,respectively.And the EPS content was determined by phenol sulfuric acid method.The EPS producing strains were preliminarily screened,bacterial spe⁃cies were identified and their diversity was analyzed by 16S rDNA sequence.The scavenging rate of 1,1⁃diphenyl⁃2⁃trinitrophenylhydrazine(DPPH)of EPS was measured and the antiviral activity of EPS against infectious bursal disease virus(IBDV)was studied to evaluate the antioxidant activity.【Result】Thirty⁃seven strains of EPS producing symbiotic and epiphytic marine bacteria were obtained.The 16S rDNA sequence analysis of the representative strains revealed that these strains were affiliated with 3 classes,4 orders,6 families,6 genera and 10 species,respectively.Among them,the dominant genus was Bacillus,accounting for 42.86%of the representative strains,and followed by Providencia(25.00%)and Vibrio(21.43%).The EPS content determination results showed that there were obvious differences in EPS production among different strains,and the results of DPPH clearance analysis showed that EPS produced by representative strains had cer⁃tain antioxidant activity,and the DPPH clearance rates were greatly different among different strains of different genera and different species strains of the same genus.EPS produced by representative strains of Bacillus predominance had the ability to inhibit IBDV replicat

关 键 词：海洋动物 共附生微生物 胞外多糖 抗氧化活性 抗病毒活性 

分 类 号：S917.1[农业科学—水产科学]