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1.
【目的】分析海洋动物肠道中抗氧化活性乳酸菌的多样性,并对活性菌株胞外与胞内代谢物清除1,1-二苯基-2-三硝基苯肼(DPPH)自由基能力进行测定。【方法】采用溶钙圈分离培养技术和DPPH自由基清除法,从湛江海域6种海洋动物肠道中分离活性乳酸;通过构建16S rDNA基因序列系统发育树,分析其多样性;利用DPPH自由基清除法,测定其抗氧化活性。【结果】共分离得到16株抗氧化活性乳酸菌,分属于细菌域厚壁菌门(Firmicutes)的4个科(Leuconostocaceae,Streptococcaceae,Lactobacillaceae,Enterococcaceae)、6个属(Weissella,Pediococcus,Leuconostoc,Lactococcus,Lactobacillus,Enterococcus),其中除菌株zy-3、LY-87、ZH-54的16S r DNA基因序列与数据库EzBioCloud中的模式菌相似性100%外,其余13株活性菌株与模式菌存在一定的遗传差异(97.42%～99.93%),菌株zy-I与模式菌株Weissella cibaria(KACC11862T)的相似性仅为97.42%,推测为Weissella cibaria属中的潜在新种;16株活性菌株胞外代谢物对DPPH的抗氧化活性均大于胞内代谢物,且5株乳酸菌株(zy-4、zy-s6、YM-49、ZH-53、ZH-54)的胞外的DPPH清除能力均在45%以上,高于其它11株菌株。【结论】湛江海域动物肠道中存在较为丰富的抗氧化活性乳酸菌,并蕴藏潜在乳酸菌新种。 相似文献
2.
从不同养殖场患病暗纹东方鱼屯(Takifaguobscurus)的鳃、肠、肝、肌肉及溃疡部位分离到9株菌株,经人工感染致病性试验,其T-22、T-11、J-2、H-3、H-5表现出较强的致病性,出现症状与自然发病鱼相同。通过对菌体形态特征、培养特性和API20E细菌生化快速鉴定试条的测定,分别鉴定为温和气单胞菌(Aeromonassobria)、豚鼠气单胞菌(Aeromonascaviae)、嗜水气单胞菌(Aeromonashydrophila)、类志贺邻单胞菌(Plesiomonasshigelloides)、霍乱弧菌(Vibriocholerae)。证实这5株菌为致病菌。药敏试验结果表明9种药物对温和气单胞菌、豚鼠气单胞菌、霍乱弧菌均有较好的抑菌效果;嗜水气单胞菌表现出明显的耐药性。氟嗪酸、环丙沙星、复合磺胺对类志贺邻单胞菌有一定抑菌效果。 相似文献
3.
工厂化养殖暗纹东方鲀致病菌的分离和鉴定 总被引：2，自引：0，他引：2
从不同养殖场患病暗纹东方鲀（Takifagu obscurus）的鳃、肠、肝、肌肉及溃疡部位分离到9株菌株，经人工感染致病性试验，其T-22、T-11、J-2、H-3、H-5表现出较强的致病性，出现症状与自然发病鱼相同。通过对菌体形态特征、培养特性和API20E细菌生化快速鉴定试条的测定，分别鉴定为温和气单胞菌（Aeromonas sobria）、豚鼠气单胞菌（Aeromonas calyioe）、嗜水气单胞菌（Aeromonas hydrophila）、类志贺邻单胞菌（Plesiomonas shigelloides）、霍乱弧菌（Vrbrio cholerae）。证实这5株菌为致病菌。药敏试验结果表明9种药物对温和气单胞菌、豚鼠气单胞菌、霍乱弧菌均有较好的抑菌效果；嗜水气单胞菌表现出明显的耐药性。氟嗪酸、环丙沙星、复合磺胺对类志贺邻单胞菌有一定抑菌效果。 相似文献
4.
【目的】准确高效分离红树林等海洋环境中产脂肽芽孢杆菌。【方法】将前期从红树林环境筛出具有抗菌活性的12株芽孢菌株作为研究菌株,采用溶血活性及排油作用对其中的可能产脂肽菌株进行初步筛选,并基于脂肽合成酶基因PCR扩增法对脂肽合成酶基因携带菌复筛,采用飞行时间质谱(TOF-MS)对所产脂肽进行鉴定。【结果】初步发现6株芽孢杆菌具有溶血活性,其中HY-5、HY-4和HN-9这3株具有排油能力,油层透明圈的直径分别为45、32和3 mm。PCR扩增检测到HY-5含有iturin、surfactin和bacillomycin D合成酶基因,HY-4含有iturin、surfactin合成酶基因,HN-9含有iturin合成酶基因。TOF-MS检测到HY-5和HY-4的发酵液含surfactin、iturin和bacillomycin 3种脂肽,HN-9的发酵液只含iturin。【结论】基于PCR与TOF-MS为核心的级联技术,建立一种海洋源脂肽产生菌快速筛选以及脂肽谱快速鉴定的方法,解决海洋源芽孢杆菌在常规培养基难合成脂肽造成的漏筛情况。 相似文献
5.
从湛江近海海水和海泥分离的229株细菌中,选出对芒果炭疽菌(Colletotrichum gloeosporioides)具有较强拮抗作用的海洋细菌BSW03,抑菌圈直径为14.0 mm。根据菌体形态、生理生化特性和16s rDNA序列分析,BSW03鉴定为枯草芽孢杆菌(Bacillus subtilis)。从9种培养基中筛选出BDPB作为BSW03的发酵培养基,通过单因子碳源、氮源试验和L9(34)正交试验对发酵培养基成分进行优化。结果表明:发酵培养基最佳配方为乳糖20 g/L,牛肉膏15 g/L,K2HPO3.3H2O 0.75 g/L,MgSO4 0.75 g/L,pH自然。转速170 r/min、温度28℃的恒温摇床培养3 d后的无菌发酵液抑菌效果最佳,抑菌圈直径为27.3 mm。 相似文献
6.
从南海海域的鱼类、贝类、海藻以及海泥样品中分离出199株海洋真菌,分属于青霉属、曲霉属和酵母属等9个属,其中以青霉属和曲霉属真菌居多,分别占28.6%和26.8%。以大肠杆菌和金黄色葡萄球菌作为指示菌,筛选出抑菌活性菌株7株,其中2株既抗大肠杆菌又抗金黄色葡萄球菌,4株抗金黄色葡萄球菌,1株抗大肠杆菌。 相似文献
7.
【目的】为开发用于害虫生物防治的细菌杀虫剂,对分离自红树林的一株沙雷氏菌进行鉴定并初步测试其杀虫活性。【方法】采用形态特征比较、细菌理化特性测定和基于16S rDNA序列构建系统发育树对从湛江红树林根际分离的菌株ZJ9进行综合鉴定,采用喂毒法和注射法进行杀虫活性测定。【结果】该菌为黏质沙雷氏菌Serratia marcescens,对草地贪夜蛾3龄幼虫7d校正死亡率为80.21%,且与苏云金芽孢杆菌和隐地杆菌无显著差异,菌体及菌液对大蜡螟老熟幼虫血腔注射24 h死亡率均达100%。【结论】菌株ZJ9为黏质沙雷氏菌,对草地贪夜蛾具有很好杀虫活性,可用作害虫的生物防治资源。 相似文献
8.
从近江牡蛎肠道中分离出21株菌,其中, 9株为革兰阳性菌, 12株革兰阴性菌。为寻找能分泌多种酶的有益微生物,研究了它们蛋白酶、脂肪酶、淀粉酶、纤维素酶的产酶能力。结果表明,有61 .9%的菌株能分泌蛋白酶或淀粉酶(各有13株菌);有52. 4%的菌株能分泌脂肪酶(11株菌);有33. 3%的菌株能产纤维素酶(7株菌)。在这21株菌中,产4种酶的有5株菌,产3种酶的3株菌,产两种酶的5株菌,产1种酶的3株菌,不产酶的仅有5株菌。不产酶的菌株仅占细菌总数的23. 8%,而各种产酶菌则高达76. 2%,由此表明细菌在近江牡蛎对食饵消化过程的重要性。 相似文献
9.
【目的】研究海洋土曲霉C23-3与不同类型海洋微生物共培养对其次生代谢产物的影响,挖掘土曲霉菌株C23-3的次生代谢潜力。【方法】将副溶血弧菌、枯草芽孢杆菌和胶红酵母的活菌或灭活菌体分别以不同时间与土曲霉C23-3共培养;采用DPPH自由基清除法和Ellman法分别评价各提取物的抗氧化和乙酰胆碱酯酶抑制活性,采用滤纸片法比较各提取物的抗菌活性,采用HPLC指纹图谱分析各提取物化学成分的差异。【结果与结论】发现不同类型的微生物与土曲霉共培养均可激活一些原本沉默的活性次级代谢产物;菌株及共培养物的化学拮抗能力、HPLC指纹图谱中的特征代谢产物变化揭示在活菌培养体系中土曲霉占竞争优势;而且灭活菌体中可能存在某些信号物质,在12 d时对土曲霉群体自感应信号分子丁内酯-I的产生具有比活菌更强的刺激作用。研究结果为深入挖掘海洋真菌代谢潜力及抗老年痴呆等活性先导化合物的发现提供基础。 相似文献
10.
近江牡蛎肠道细菌及其产酶能力 总被引：1，自引：0，他引：1
从近江牡蛎肠道中分离出21株菌，其中，9株为革兰阳性菌，12株革兰阴性菌。为寻找能分泌多种酶的有益微生物，研究了它们蛋白酶、脂肪酶、淀粉酶、纤维素酶的产酶能力。结果表明，有61．9％的菌株能分泌蛋白酶或淀粉酶(各有13株菌)；有52．4％的菌株能分泌脂肪酶(11株菌)；有33．3％的菌株能产纤维素酶(7株菌)。在这21株菌中，产4种酶的有5株菌，产3种酶的3株菌，产两种酶的5株菌，产1种酶的3株菌，不产酶的仅有5株菌。不产酶的菌株仅占细菌总数的23．8％，而各种产酶菌则高达76．2％，由此表明细菌在近江牡蛎对食饵消化过程的重要性。 相似文献
11.
Seventy-eight marine fungal strains were isolated from sediment samples collected off the coast of Nanji Island,Wenzhou,Zhejiang Province,China.Antibacterial screening using the agar disc method showed that 19 of the isolated strains could inhibit at least one pathogenic Vibrio from Pseudosciaena crocea.Subsequent screening confirmed that nine strains produced antibacterial metabolites that had activity against one or several types of pathogenic Vibrio.Strain NJ0104 had the widest antimicrobial spectrum and strong activity,particularly against Vibrio parahaemolyticus-MM0810072.A preliminary study of NJ0104 antibacterial metabolites demonstrated that they had thermal stability up to 80°C,ultraviolet stability up to 40 min and pH stability between 4.0-7.0.In addition,the antibacterial metabolites were readily soluble in butanol.To identify the specific strain,the ITS-5.8S rDNA regions of NJ0104 were PCR amplified and sequenced.Based on the combination of phenotypic and genotypic data,the strain was identified as Arthrinium sp. 相似文献
12.
The purpose of this study was to investigate the antibacterial activity of extracts from Zostera marina against the pathogens of Apostichopus japonicus skin ulceration disease. When 95% ethanol (v/v) solvent was used to extract Zostera marina at 50°C, aqueous extract (ZA) showed obvious bacteriostatic effects on the tested bacterial strains (inhibition halo diameters
between 8.23 mm and 13.62 mm), whereas the ethyl acetate extract (ZE) was almost inactive. The minimal inhibitory concentration
(MIC) of ZA against four pathogens were homogeneous at 12.8 g L−1. ZA components were analyzed by thin layer chromatography (TLC) assay and six fractions were obtained. In another study,
the six fractions showed inhibitory effects against the tested bacteria while their functions seemed to counteract the ZA
activity. 相似文献
13.
S. Satheesh A. R. Soniamby C. V. Sunjaiy Shankar S. Mary Josephine Punitha 《中国海洋大学学报(英文版)》2012,11(3):354-360
The present study aimed at assessing the antifouling activity of bacteria associated with marine sponges. A total of eight bacterial strains were isolated from the surface of sponge Sigmadocia sp., of them, SS02, SS05 and SS06 showed inhibitory activity against biofilm-forming bacteria. The extracts of these 3 strains considerably affected the extracellular polymeric substance producing ability and adhesion of biofilm-forming bacterial strains. In addition to disc diffusion assay, microalgal settlement assay was carried out with the extracts mixed with polyurethane wood polish and coated onto stainless steel coupons. The extract of strain SS05 showed strong microalgal settlement inhibitory activity. Strain SS05 was identified as Bacillus cereus based on its 16S rRNA gene. Metabolites of the bacterial strains associated with marine invertebrates promise to be developed into environment-friendly antifouling agents. 相似文献
14.
In recent years, red tides occurred frequently in coastal areas worldwide. Various methods based on the use of clay, copper sulfate, and bacteria have been successful in controlling red tides to some extent. As a new defensive agent, marine microorganisms are important sources of compounds with potent inhibitory bioactivities against red-tide microalgae, such as Gymnodinium sp. （Pyrrophyta）. In this study, we isolated a marine bacterium, HSB07, from seawater collected from Hongsha Bay, Sanya, South China Sea. Based on its 16S rRNA gene sequence and biochemical characteristics, the isolated strain HSB07 was identified as a member of the genus Halomonas. A crude ethyl acetate extract of strain HSB07 showed moderate inhibition activity against Gymnodinium sp. in a bioactive prescreening experiment. The extract was further separated into fractions A, B, and C by silica gel column chromatography. Fractions B and C showed strong inhibition activities against Gymnodinium. This is the first report of inhibitory activity of secondary metabolites of a Halomonas bacterium against a red-tide-causing microalga. 相似文献
15.
Quorum sensing(QS)disruption is considered as a potential alternative strategy to combat bacterial diseases in aquaculture.In this study,we isolated and identified bacteria degrading QS molecules from pond sediment and fish intestine.A total of 132 strains were obtained in the enrichment culture,of which two strains were identified as Enterobacter sp.f003 and Staphylococcus sp.sw120,being isolated from the fish intestine and pond sediment,respectively.We found that strains f003 and sw120 could degrade acyl-homoserine lactones(AHLs)and cause no hemolysis of sheep red blood cells.The AHL lactonase(aiiA)homologous gene in the two strains was detected in PCR amplification and the high-degrading activity to N-hexanoyl-L-homoserine lactone(C6-HSL)and AHLs secreted from pathogenic Aeromonas hydrophila was assessed.Meanwhile,the artificial infection of cyprinid Carassius auratus gibelio with intraperitoneal injection showed that the two strains were avirulent.Therefore,the obtained indigenous bacteria are candidate probiotics against pathogenic A.hydrophila in aquaculture. 相似文献
16.
YUE Lixi MA Chunling and CHI Zhenming* UNESCO Chinese Center of Marine Biotechnology Ocean University of China Qingdao P.R.China 《中国海洋大学学报(英文版)》2006,5(4)
1IntroductionWater co-produced with oil and gas recovery istermed oil-field produced water.This water is consid-ered to be of the largest volume in the waste streamfromoil and gas production processes.The volume ofproduced water can be more than10ti mes t… 相似文献
17.
Yin Qunjian Zhang Weijia Li Xuegong Zhou Lihong Qi Xiaoqing Zhang Chan Wu Long-Fei 《中国海洋湖沼学报》2019,37(1):210-222
Trimethylamine N-oxide (TMAO) is widely dispersed in marine environments and plays an important role in the biogeochemical cycle of nitrogen. Diverse marine bacteria utilize TMAO as carbon and nitrogen sources or as electron acceptor in anaerobic respiration. Alteration of respiratory component according to the pressure is a common trait of deep-sea bacteria. Deep-sea bacteria from different genera harbor high hydrostatic pressure (HHP) inducible TMAO reductases that are assumed to be constitutively expressed in the deep-sea piezosphere and facilitating quick reaction to TMAO released from fish which is a potential nutrient for bacterial growth. However, whether deep-sea bacteria universally employ this strategy remains unknown. In this study, 237 bacterial strains affiliated to 23 genera of Proteobacteria, Bacteroidetes, Firmicutes and Actinobacteria were isolated from seawater, sediment or amphipods collected at different depths. The pressure tolerance and the utilization of TMAO were examined in 74 strains. The results demonstrated no apparent correlation between the depth where the bacteria inhabit and their pressure tolerance, regarding to our samples. Several deep-sea strains from the genera of Alteromonas, Halomonas, Marinobacter, Photobacterium, and Vibrio showed capacity of TMAO utilization, but none of the isolated Acinebacter, Bacillus, Brevundimonas, Muricauda, Novosphingobium, Rheinheimera, Sphingobium and Stenotrophomonas did, indicating the utilization of TMAO is a species-specific feature. Furthermore, we noticed that the ability of TMAO utilization varied among strains of the same species. TMAO has greater impact on the growth of deep-sea isolates of Vibrio neocaledonicus than shallow-water isolates. Taken together, the results describe for the first time the TMAO utilization in deep-sea bacterial strains, and expand our understanding of the physiological characteristic of marine bacteria.
相似文献18.
《中国海洋湖沼学报》2020,(2)
Trimethylamine N-oxide(TMAO) is one of the most important nutrients for bacteria in the deep-sea environment and is capable of improving pressure tolerance of certain bacterial strains.To assess the impact of TMAO on marine microorganisms,especially those dwelling in the deep-sea environment,we analyzed the bacterial community structure of deep-sea sediments after incubated under different conditions.Enrichments at 50 MPa and 0.1 MPa revealed that TMAO imposed a greater influence on bacterial diversity and community composition at atmospheric pressure condition than that under high hydrostatic pressure(HHP).We found that pressure was the primary factor that determines the bacterial community.Meanwhile,in total,238 bacterial strains were isolated from the enrichments,including 112 strains a ffiliated to 16 genera of 4 phyla from the Yap Trench and 126 strains a ffiliated to 11 genera of 2 phyla from the Mariana Trench.Treatment of HHP reduced both abundance and diversity of isolates,while the presence of TMAO mainly af fected the diversity of isolates obtained.In addition,certain genera were isolated only when TMAO was supplemented.Taken together,we demonstrated that pressure primarily defines the bacterial community and culturable bacterial isolates.Furthermore,we showed for the first time that TMAO had distinct influences on bacterial community depending on the pressure condition.The results enriched the understanding of the significance of TMAO in bacterial adaptation to the deep-sea environment. 相似文献
19.
Thirty-six strains of marine actinomycetes were isolated from a sample of marine sediment collected from the Yellow Sea and evaluated in terms of their inhibitory activity on the growth of Aspergillus parasiticus and the production of norsolorinic acid using dual culture plate assay and agar diffusion methods. Among them, three strains showed strong antifungal activity and were subsequently identified as Streptomyces sp. by 16S rRNA gene sequencing analysis. The supernatant from the fermentation of the MA01 strain was extracted sequentially with chloroform and ethyl acetate, and the activities of the extracts were determined by tip culture assay. The assay results show that both extracts inhibited mycelium growth and toxin production, and the inhibitory activities of the extracts increased as their concentrations increased. The results of this study suggest that marine actinomycetes are biologically important for the control of mycotoxins, and that these bacteria could be used as novel biopesticides against mycotoxins. 相似文献
20.
YUE Lixi MA Chunling CHI Zhenming 《中国海洋大学学报(英文版)》2006,5(4):333-338
Seventy-nine strains of bioflocculant-producing bacteria were isolated from 3 activated sludge samples. Among them, strain MYC was found to have the highest and stable flocculating rate for both kaolin clay suspension and oil-field produced water. The bacterial strain was identified as Klebsiella sp. MYC according to its morphological and biochemical characteristics and 16SrDNA sequence. The optimal medium for bioflocculant production by this bacterial strain was composed of cane sugar 20 g L^-1, KH2PO4 2 g L^-1, K2HPO4 5 g L^- 1, （ NH4）2SO4 0.2 g L^-1, urea 0.5 g L^- 1 and yeast extract 0.5 g L^- 1, the initial pH being 5.5. When the suspension of kaolin clay was treated with0.5% of Klebsiella sp. MYC culture broth, the flocculating rate reached more than 90.0% in the presence of 500mg L^-1 CaCI2, while the flocculating rate for oil-field produced water was near 80.0% in a pH range of 7.0 - 9.0 with the separation of oil and suspended particles from the oil-field produced water under similar conditions. The environment-friendly nature of the bioflocculant and high flocculating rate of the strain make the bioflocculant produced by Klebsiella sp. MYC an attractive bioflocculant in oil-field produced water treatment. 相似文献