鱿鱼(Squid)肝脏蛋白酶解物中ACE活性抑制肽的分离纯化及活性分析

为提高鱿鱼加工下脚料的利用率,以秘鲁鱿鱼肝脏为研究对象,采用生物酶解技术和凝胶蛋白分离技术等对其进行研究。研究结果表明:鱿鱼肝脏蛋白酶解液经过超滤处理后(分子质量为20k Da),用Sephadex G-100初步分离,得到五个组分,对分离的组分进行研究,结果表明降血压活性能力最强的是组分二,测定其半抑制浓度(IC50)为1.8mg/m L。对组分二进行活性条件分析,结构表明其ACE抑制活性在温度0—100°C、p H 1—12之间基本没有变化。最后用DEAE阴离子交换柱和Sephadex LH-20对组分二继续分离纯化,得到组分六和组分七,测定其半抑制浓度(IC50)分别达到1.52 mg/m L和2.16 mg/m L。本研究可为利用鱿鱼加工下脚料开发降血压活性肽产品提供理论基础。     

海鞘中的抗肿瘤生物活性物质

综述了海鞘中发现的数十种抗肿瘤活性物质,包括其活性、来源等,对其中重要者,如Ecteinascidians 743和Psedodistomins D-F等活性物质抗肿瘤的作用机理作了较详细的介绍,并概述了国内该领域的研究状况。     

Diversity and bioactivity of actinomycetes from marine sediments of the Yellow Sea

Among the 116 actinomycetes collected from marine sediments of the Yellow Sea,56 grew slowly and appeared after 2?3 weeks of incubation.Among the 56 strains,only 3 required seawater(SW) for growth,and 21 grew well in the medium prepared with SW rather than distilled water(DW),while the remaining 32 grew well either with SW or with DW.Six representatives with different morphological characteristics,including 1 SW-requiring strain and 5 well-growing with SW strains,were selected for phy-logenetic analysis based on 16S rRNA gene.Two strains belong to Micrococcaceae and Nocardiopsaceae respectively.The other 4 strains belong to the family of Streptomycetaceae.In the analyzed 6 strains,one was related to Nocardiopsis spp.and the other three were related to Streptomyces spp.,representing new taxa.Bioactivity testing of fermentation products from 3 SW-requiring strains and 21 well-growing with SW strains revealed that 17 strains possessed remarkable activities against gram-positive pathogen or/and tumor cells,suggesting that they were prolific resources for natural drug discovery.     

Preparation by enzymolysis and bioactivity of iron complex of fish protein hydrolysate （Fe-FPH）from low value fish

Preparation of Fe^2＋ chelate of fish protein hydrolysate （Fe-FPH） obtained from low value fish proteins was introduced and its bioactivity was studied by compound enzymolysis. The optimum conditions for hydrolysate chelating Fe^2＋ are DH （degree of hydrolysis） at 5%, pH 7.0, 20℃ and 15 min chelating time for FM （material not being defatted）. Four types of Fe-FPH including CA （deposit after chelating）, CB （deposit in 50% of absolute ethanol solution）, CC （suspended deposit in 80% of absolute ethanol solution）, and CD （bottom deposit in 80% of absolute ethanol solution） were fractionated with absolute ethanol from FM. Structural analysis through infra-red spectrum revealed that Fe^2＋ was combined strongly with amino-group and carboxyl-group in each chelate and each Fe^2＋ could form two five-member ring structures. All of the four chelates were shown more significant antioxidative activity and can be used as natural hydrophobic and hydrophilic antioxidant. Among all the chelates, the CB possesses the most effective antioxidative activity at 92% as high as that of a-tocopherol. Among all Fe-FPHs, only CD showed the most effective antibacterial activity against Escherichia coli, Staphylococcus aureus, Salmonella typhi, and Bacillus subtilis and can be used as natural antibacterial. It provides a more effective way for utilization of low value fish proteins and key information of Fe-FPH as additive in food industry.     

黑河甘肃段浮游植物群落结构演变趋势

为探究西北干旱区内陆河流域水生态系统时空演变规律,2017年7月对黑河甘肃段进行了浮游植物的采样调查,并收集1981、1997、2008年浮游植物夏季调查数据,分析黑河上中下游浮游植物物种、生物多样性和优势种等群落结构的演变特征,同时提出生物活动力指标以表征河流生物的活动能力和活跃程度。结果表明：在空间分布上,黑河中游在各年份都具有最为丰富稳定的浮游植物群落结构,物种数（61属）、生物多样性指数（2.87）和生物活动力指数（0.194万cells·hm^-2）均高于上下游。在时间尺度上,上游浮游植物群落变得持续丰富;中游从1981年持续衰落到2008年后出现反转并快速恢复到2017年更为丰富和活跃的水平;下游则呈现出持续衰落的态势。以1981年为基准,黑河中游水域面积到2010年减小5.2%,浮游植物生物活动力降低了16.5%,到2017年水域面积增加1.2%,浮游植物生物活动力增加了4.3%。黑河浮游植物对流域天然湿地及水域的变化具有强烈的敏感性和依赖性,浮游植物演变特征与湿地水域面积变化趋势一致。     

Construction of a Metagenomic DNA Library of Sponge Symbionts and Screening of Antibacterial Metabolites

To study the bioactive metabolites produced by sponge-derived uncultured symbionts, a metagenomic DNA library of the symbionts of sponge Gelliodes gracilis was constructed. The average size of DNA inserts in the library was 20 kb. This library was screened for antibiotic activity using paper disc assaying. Two clones displayed the antibacterial activity against Micrococcus tetragenus. The metabolites of these two clones were analyzed through HPLC. The result showed that their metabolites were quite different from those of the host E. coli DH5α and the host containing vector pHZ132. This study may present a new approach to exploring bioactive metabolites of sponge symbionts.     

一株海绵共附生真菌Pleosporaceae sp.中甾体类化合物及其生物活性

在生物活性测定指导下,综合运用硅胶柱层析、凝胶柱层析以及半制备HPLC等方法,从南海海绵Xestospongiatestudinaria来源的一株共附生真菌Pleosporaceae sp.发酵液的乙酸乙酯提取物中分离鉴定出5个甾体类化物,通过NMR,MS等波谱技术鉴定其结构分别为:(22E,24R)-5α,8α-epidioxy-ergosta-6,22-dien-3β-ol(1),(22E,24R)-5α,8α-epidioxy-ergosta-6,9,22-trien-3β-ol(2),(22E)-ergosta-5,7,22-trien-3β-ol(3),ergosta-6α-hydroxy-4,22-dien-3-one(4),(22E)-5α-cholesta-7,22-diene-3β,5α,6β-triol(5)。这些化合物均为首次从Pleosporaceae属真菌中分离获得。化合物1,4和5具有较强的卤虫Ar-temia salina致死活性,化合物1还显示强的抗藤壶Balanus amphitrite附着活性,其EC50为0.85μg/mL。     

Growth dynamics and bioactivity variation of the Mediterranean demosponges Agelas oroides (Agelasida, Agelasidae) and Petrosia ficiformis (Haplosclerida, Petrosiidae)

Growth dynamics and bioactivity variation of the Mediterranean demosponges Agelas oroides and Petrosia ficiformis were investigated over 15 months at Paraggi and Colombara within the Marine Reserve of Portofino Promontory (Mediterranean Sea, Ligurian Sea, Italy). For both species, growth rates varied between individuals and were unaffected by initial sponge size. The two species showed a different trend in growth pattern: A. oroides did not vary significantly between seasons, sites and depths; in contrast, some individuals of P. ficiformis showed a seasonal pattern, shrinking during winter as water temperature decreased and growing during summer when water temperature increased. Differences in growth between the two species may result from different reproductive cycles, food availability, species-specific thermophily and patterns of spatial competition. Moreover, spatial competition probably induced sponges to produce bioactive secondary molecules. Spatial and temporal variation of bioactivity of both species was examined for the first time by studying its effect on human neuroblastoma cells. The bioactivity of A. oroides extracts differed significantly between seasons, sites and depths, whereas the cytotoxicity of P. ficiformis differed significantly between seasons and depths (differences for sites were not determined). These results suggest the possible influence of environmental factors on bioactive metabolite biosynthesis.     

生物活动在吉林东南部寒武纪沉积铜形成过程中的作用

吉林东南部寒武纪沉积铜主要为沉积和后期热液改造综合作用的产物。它们在形成过程中，生物活动起了很大的作用，生物直接成因标志和间接成因迹象在本区都有体现。前者主要表现在由藻类群落形成的有机质胶体和胶团中聚集了大量的黄铜矿和黄铁矿颗粒，草莓状构造即为其典型构造之一。后者则为由生物形成的有机酸在通过红色矿源层时形成可溶性有机铜盐，并运移到适当部位富集起来，形成具一定程度的矿化现象。“圈闭构造”在形成本区这类矿化现象中起到了十分重要的作用。     

海藻酸作为活性药物和新型药用敷料的开发

海藻酸是我国海洋水产资源的重要组成部分,21世纪被称为海洋和生物世纪,在“蓝色医药产业”正在兴起的今日,将海藻酸系列开发为活性药物和新型药用敷料具有重要意义。文中归纳了海藻酸胶的生物学活性、作为活性药物的应用和新型药用敷料的开发,并分析了国内海藻酸产品的现状,阐述了海藻酸胶的开发前景。