Page 56 - 《广西植物》2020年第3期
P. 56

3 3 6                                 广  西  植  物                                         40 卷
    ( 1. Guangxi Key Laboratory of Maine Environmental Scienceꎬ Guangxi Academy of Sciencesꎬ Nanning 530007ꎬ Chinaꎻ 2. Guangxi Key Laboratory of
    Marine Natural Products and Combinatorial Biosynethesis Chemistryꎬ Guangxi Academy of Sciencesꎬ Nanning 530007ꎬ Chinaꎻ 3. National Engineering
       Research Center for Non ̄Food Biorefineryꎬ State Key Laboratory of Non ̄Food Biomass and Enzyme Technologyꎬ Guangxi Key Laboratory of
          Bio ̄refineryꎬ Guangxi Biomass Engineering Technology Research Centerꎬ Guangxi Academy of Sciencesꎬ Nanning 530007ꎬ China )

       Abstract: Mangrove endophytes play an important role in the material cycleꎬ energy transfer and health maintenance of
       mangrove plants. In order to enrich microbiological resources for further revealing the functional diversity of the endo ̄
       phytes microorganism in mangrove plantsꎬ in this studyꎬ we investigated the distribution and diversity of endophytic and
       rhizospheric bacteria of Aegiceras corniculatum collected from Beihai Cityꎬ and studied the anti ̄thrombotic activities of
       those strains. The endophytic and rhizospheric bacteria were isolated from A. corniculatum by using six different isolation
       media. The anti ̄thrombotic activities of all species were screened out by thrombolysis experiment in vitro. The results
       were as follows: (1) Based on the phylogenetic analysis of 16S rRNA gene sequenceꎬ a total of 125 strains were ob ̄
       tained from the tissue and rhizosphere soil of A. corniculatum. They were classified into 74 speciesꎬ 39 generaꎬ 27 fami ̄
       lies and 3 phylas of Proteobacteriaꎬ Actinobacteria and Firmicutes. Bacillus sp. was the dominant genusꎬ and the total
       rate was 13.5%. (2) The results of anti ̄thrombotic activity test showed that 18 strains with anti ̄thrombotic activity were
       screened outꎬ and the total positive rate reached to 24.32%. The activity of the strains was further verified by the re ̄
       screening and re ̄verification test. The strains of B1850ꎬ B1989 and B2632 with strong anti ̄thrombotic activity were ob ̄
       tained. To sum upꎬ there are abundant culturable bacterial resources in Aegiceras corniculatum in Beihai of Guangxiꎬ
       which could be a potential source for the discovery of new plasminogen and thrombolytic drugs.
       Key words: Aegiceras corniculatumꎬ endophytic bacteriaꎬ rhizospheric bacteriaꎬ diversityꎬ anti ̄thrombotic activity


       血栓性疾病是一类严重威胁人类健康的常见                           酶ꎮ 刘晨光等(2001) 分离到一株海洋假单胞菌
   病、多发病ꎬ常表现为心绞痛、心肌梗死、脑栓塞和                           (Pseudomonas sp.)可产生较强的直接溶解纤维蛋
   脑梗死等ꎬ多以中老年人为主要发病群体ꎬ现发病                            白和具有抗血栓活性的碱性蛋白酶 MPAPꎮ 这些
   人群逐渐趋于年轻化ꎬ且发病率与死亡率在不断                             为从海洋微生物来源寻找抗血栓的药物提供了很
   上升(乔德水等ꎬ2009ꎻJäremo et al.ꎬ 2013)ꎮ 血栓             好的依据ꎮ 桐花树系红树林中广布种之一ꎬ广泛
   性疾病的起因主要是血管腔中形成血栓使其变得                             分布于亚洲至大洋洲热带海岸ꎬ在我国的广东、广
   狭窄或闭塞ꎬ导致主要器官缺血或梗死ꎮ 而血栓                            西、福建 和 海 南 等 省 ( 区) 均 有 分 布 ( 缪 绅 裕 等ꎬ
   是人体内血液组成成分在血管或心脏内形成的凝                             2007)ꎮ 我国的桐花树由于受到常年全日潮水的
   块ꎬ可脱落凝块随血液流至远端ꎬ从而堵塞血管腔                            浸淹ꎬ使之生长状况、营养发育、生物量分配、激素
   (Sun et al.ꎬ 2008)ꎮ 目前临床上主要有三大类治                  水平和相关酶系等方面的生理生态性质表现出梯
   疗血栓性疾病的药物ꎬ即抗血小板类、抗凝血类和                            度性反应(何斌源等ꎬ2007)ꎬ其内生菌长期生活于
   溶血栓药物ꎮ 传统的溶血栓药物在临床上虽具有                            植物体内的特殊环境中并与之协同进化ꎮ 植物体
   确切的疗效和良好的安全性ꎬ但其存在的半衰期                             为其提供生长所必需的能量和营养的同时ꎬ内生
   短、纤维蛋白特异性低和价格贵等缺点也不容忽                             菌又会通过自身的代谢、信号传导对植物体产生响
   视(翁郁华等ꎬ2010)ꎮ 因此ꎬ寻找能解决上述问题                        应(文才艺等ꎬ2004)ꎮ 本研究以广西北海滩涂的桐
   的溶血栓药物具有广泛的应用前景ꎮ                                  花树中分离、培养和鉴定出的植物内生和根际细菌
       近年来ꎬ海洋微生物是新型纤溶酶的重要来                           为样本ꎬ旨在筛选出具有高效抗血栓活性的菌株ꎮ

   源之一ꎮ Lakshmi et al.(2013) 从海洋沙雷菌( Ser ̄
   ratia sp. RSPB11) 分离到一种具有纤维蛋白水解                   1  材料与方法
   活性和高热稳定的碱性金属蛋白酶ꎮ 李占强等
   (2009)从南海沉积物中分离到的短小芽孢杆菌                           1.1 材料
   (Bacillus pumilus B5815)ꎬ其纤溶酶活性好且产酶               1.1.1 样本来源  桐花树于 2018 年 8 月在广西北
   量高ꎮ Huang et al. ( 2013) 从海洋枯 草 芽 孢 杆 菌           海滩涂(108°50′42″ E、 21°55′25″ N) 采集ꎮ 样品
   (Bacillus subtilis HAS ̄3)分离到一种纤维蛋白水解              装于密封袋ꎬ4 ℃ 低温保藏带回实验室ꎬ尽快完成
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