2种微藻总RNA提取方法的比较

以微茫藻和莱茵衣藻为材料,比较Trizol试剂法和SDS-LiCl沉淀法提取2种微藻总RNA的效果,以期筛选出适合微藻RNA的提取方法。结果表明,SDS-LiCl沉淀法能从微茫藻中提取高质量的RNA,而Trizol法和SDS-LiCl沉淀法均能从莱茵衣藻中获得高质量的RNA,但Trizol法更为简单有效。RT-PCR结果表明,SDS-LiCl沉淀法提取的微茫藻总RNA和Trizol法提取的莱茵衣藻总RNA都能直接用于分子克隆和基因表达分析等分子生物学实验。     

链带藻Desmodesmus sp.QL96蛋白质的营养价值评价与生理活性研究

链带藻Desmodesmus sp.QL96是从我国西藏地区分离的一株链带藻,前期研究表明其含有丰富的蛋白质.本文对这株链带藻的主要细胞组分的含量进行了检测,并采用改进的TCA-丙酮法提取其蛋白质,分析了蛋白粗提物的氨基酸组成及其体外抗氧化和抑菌活性.结果表明:链带藻Desmodesmus.sp.QL96的蛋白质平均含...     

花生脂质转运蛋白家族基因的克隆与表达分析

植物脂质转运蛋白（Lipid transfer protein,LTP）作为一类小分子碱性蛋白在脂类物质的运输、生殖发育,抵御不良环境等方面具有重要的作用,此外,LTP还作为一种过敏原存在。通过构建花生未成熟种子全长cDNA文库,克隆到了5类LTP基因,按照编码蛋白分子量的大小命名为AhLTP-11.5,AhLTP-12.8,AhLTP-11.8,AhLTP-8.3和AhLTP-19.2。生物信息学预测表明AhLTP-11.5属于AAI_LTSS蛋白家族的nsLTP1亚族,AhLTP-11.5编码蛋白的N端有26个氨基酸残基的信号肽序列,ProtCompv8.0预测结果显示该蛋白为分泌蛋白,胞外定位。从系统发育树中可以看出,花生的AhLTP-11.5和拟南芥的AthLTP亲缘关系较近。半定量RT-PCR结果表明AhLTP-11.5基因在花生茎、叶、花和种子中均有表达,在根中几乎检测不到 在花生种子的不同发育时期AhLTP-11.5基因在DAP15d时表达量较低,20d以后表达趋于稳定。     

油脂微藻的研究进展

本文简述了油脂微藻的种类、含油量和脂肪酸成分以及主要用途,介绍了微藻的油脂代谢调控和改良技术研究进展,分析了目前大规模生产中存在的主要问题以及今后发展重点。     

基于柱前衍生化GC-MS的炒青绿茶加工过程中初级代谢物变化规律研究

茶叶中的一些初级代谢产物前人研究较少,为了探明在炒青绿茶加工过程中这些初级代谢产物的变化规律,本研究以龙井43品种为原料制作了炒青绿茶,并采用了基于柱前衍生化的气相色谱-质谱联用法(GC-MS)对其进行测定。结果共鉴定出60种化合物,其中相对含量较高的为有机酸类、糖类、糖类衍生物。偏最小二乘法判别分析模型可成功区分炒青绿茶各个加工工序,并筛选出了关键差异化合物26种,聚类分析结果表明,这26种化合物在加工过程中的含量变化规律可分为以下3类:高→低:2-酮戊二酸、阿拉伯糖、没食子酸、吡喃葡萄糖醛酸、甘油葡萄糖苷、核糖、半乳糖、果糖、葡萄糖、磷酸、4-酮葡萄糖、核糖酸-1,4-内酯、甘露醇;高→低→高:尿黑酸、蔗糖、肌醇半乳糖苷、苏糖酸、松二糖、核糖酸、肌醇和柠檬酸;低→高→低:赤藓糖-1,4-内酯、磷酸氧丙基酯、焦谷氨酸、奎尼酸、己二酸。有机酸主要呈现先上升后下降趋势,糖类除蔗糖外主要呈现下降趋势。     

4株海洋红酵母分离鉴定及其代谢产物分析

从湛江特呈岛、东海岛及水产品市场采集海泥、红树叶、花、果、土壤、带鱼、章鱼、鱿鱼等样品,用于海洋红酵母分离;通过形态、培养特性观察及26S rDNA D1/D2区域序列分析对分离菌株进行鉴定,并作代谢产物分析。结果表明：从样品分离菌中鉴定出4株海洋红酵母,分别是胶红酵母ZJZ1、胶红酵母ZJD2、粘红酵母ZJN5和红酵母ZJH8;4株红酵母均产生类胡萝卜素、粗多糖、蛋白酶、淀粉酶、纤维素酶、维生素B1、维生素B2和维生素B6;胶红酵母ZJD2产生的类胡萝卜素含量最高,为155.86 μg/g;胶红酵母ZJZ1产生的蛋白酶和维生素B6含量最高,为188.96 U/mL和1.14 μg/mL;粘红酵母ZJN5产生的维生素B1和维生素B2含量最高,为9.89 μg/mL和6.65 μg/mL;红酵母ZJH8产生的粗多糖、淀粉酶和纤维素酶含量最高,为14.696 μg/mL、99.271 U/mL和1.913 U/mL。     

大豆脂质转运蛋白基因GmLTP3的特征分析

将芝麻的SiLTP3序列与大豆的核苷酸序列进行blast比对,发现大豆含有与芝麻该基因同源性高达94%的序列,克隆该基因并命名为GmLTP3。通过GmLTP3的核苷酸序列推测出其氨基酸序列,利用软件进行多重序列比对和系统发育树构建,发现该氨基酸序列与已确定功能的大豆脂质转运蛋白同源性高达99%,与蒺藜苜蓿和巴旦杏的进化距离最近。采用实时荧光定量PCR法对GmLTP3基因进行定量检测,组织表达分析表明,GmLTP3属于组成性表达基因,在大豆的根、茎、叶、花、萌发的种子中均有表达,并且在花蕾、茎和萌发的种子中表达量较高,在根、叶中表达量较低。非生物胁迫诱导表达分析表明,GmLTP3基因能够对IAA、ABA、PEG、NaCl和冷害作出应答。胁迫处理2 h后,GmLTP3表达量均有下调趋势;胁迫处理12 h后,IAA、ABA、PEG、NaCl诱导GmLTP3的表达量均有不同程度的上调,冷害处理则继续下调表达量。     

辣椒非特异性脂质转移蛋白基因CaLTP1的克隆及表达分析

非特异性脂质转移蛋白(nsLTPs)是植物中大量存在的小分子脂类结合蛋白,具有多种生物学功能。从辣椒cDNA文库中筛选得到1个nsLTPs基因,命名为CaLTP1;序列分析结果表明:该基因全长cDNA序列为1 211 bp,推测编码1个包含129个氨基酸残基的前体蛋白。CaLTP1蛋白含有典型的脂质转移蛋白N-端信号肽,保守的AAI结构域和半胱氨酸位点。预测CaLTP1蛋白含有多种功能位点,包括3个CK2磷酸化位点,3个N-豆蔻酰化位点和1个PKC磷酸化位点。实时荧光定量分析组织特异性表达模式表明,CaLTP1在辣椒茎、叶、花中表达量升高。     

家兔肝脏乌头碱代谢产物的提取分离和初步鉴定方法研究

乌头总碱染毒家兔,对其肝脏中的乌头碱代谢产物进行了提纯分离,采用薄层层析法检出乌头碱的代谢产物,其产物的化学结构、是否为乌头碱代谢所特有的,尚需进一步研究。但此项研究方法和条件可用于动物肝脏中乌头碱代谢产物的进一步研究过程。     

氮元素缺乏对微藻氮代谢相关基因表达的影响

以微茫藻为材料,利用抑制差减杂交技术,分离鉴定了10种与已知功能基因具有较高同源性的基因片段,这些片段的同源基因均与氮源的吸收利用相关。实时荧光定量PCR验证了7种基因在氮缺乏条件下转录水平明显上调,包括:硝酸还原酶基因、NMT1/THI5家族蛋白基因、N-羟甲基-L-丙氨酸脱氢酶基因、核糖体蛋白L36a基因、FAD/NAD(P)结合的氧化还原酶基因、NADH:细胞色素b5还原酶基因和细胞色素cd1-亚硝酸还原酶类似基因。而天冬氨酸转氨酶、红细胞膜蛋白7.2b和γ-谷氨酰磷酸还原酶这3种基因在氮缺乏时下调表达。     

转录组揭示自养和混合培养栅藻油脂代谢途径差异

为探讨混合培养条件下栅藻脂质高产的调控机理,对栅藻(Desmodesmus sp.)分别进行自养和混合培养,使用转录组测序对比了Desmodesmus sp.在两种培养方式下油脂代谢途径差异.结果表明,混合培养组上调基因共1081个,下调基因共575个,非显著差异表达基因总共23331个.差异基因GO富集主要在光合作用...     

Extracellular Metabolites from Industrial Microalgae and Their Biotechnological Potential

Industrial microalgae, as a big family of promising producers of renewable biomass feedstock, have been commercially exploited for functional food, living feed and feed additives, high-value chemicals in nutraceuticals, cosmeceuticals, and chemical reagents. Recently, microalgae have also been considered as a group that might play an important role in biofuel development and environmental protection. Almost all current products of industrial microalgae are derived from their biomass; however, large amounts of spent cell-free media are available from mass cultivation that is mostly unexploited. In this contribution we discuss that these media, which may contain a remarkable diversity of bioactive substances are worthy to be recovered for further use. Obviously, the extracellular metabolites from industrial microalgae have long been neglected in the development of production methods for valuable metabolites. With the advances in the last ten years, more and more structures and properties from extracellular metabolites have been identified, and the potential utilization over wide fields is attracting attention. Some of these extracellular metabolites can be potentially used as drugs, antioxidants, growth regulators or metal chelators. The purpose of this review is to provide an overview of the known extracellular metabolites from industrial microalgae which might be of commercial interest. The attention mainly focuses on the reports of extracellular bioactive metabolites and their potential application in biotechnology.     

Investigation on Metabolites in Structural Diversity from the Deep-Sea Sediment-Derived Bacterium Agrococcus sp. SCSIO 52902 and Their Biosynthesis

Deep-sea sediment-derived bacterium may make full use of self-genes to produce more bioactive metabolites to adapt to extreme environment, resulting in the discovery of novel metabolites with unique structures and metabolic mechanisms. In the paper, we systematically investigated the metabolites in structurally diversity and their biosynthesis from the deep-sea sediment-derived bacterium Agrococcus sp. SCSIO 52902 based on OSMAC strategy, Molecular Networking tool, in combination with bioinformatic analysis. As a result, three new compounds and one new natural product, including 3R-OH-1,6-diene-cyclohexylacetic acid (1), linear tetradepsipeptide (2), N¹,N⁵-di-p-(EE)-coumaroyl-N¹⁰-acetylspermidine (3) and furan fatty acid (4), together with nineteen known compounds (5–23) were isolated from the ethyl acetate extract of SCSIO 52902. Their structures were elucidated by comprehensive spectroscopic analysis, single-crystal X-ray diffraction, Marfey’s method and chiral-phase HPLC analysis. Bioinformatic analysis revealed that compounds 1, 3, 9 and 13–22 were closely related to the shikimate pathway, and compound 5 was putatively produced by the OSB pathway instead of the PKS pathway. In addition, the result of cytotoxicity assay showed that compound 5 exhibited weak cytotoxic activity against the HL-60 cell line.     

The Chemically Highly Diversified Metabolites from the Red Sea Marine Sponge Spongia sp.

A polyoxygenated and halogenated labdane, spongianol (1); a polyoxygenated steroid, 3β,5α,9α-trihydroxy-24S-ethylcholest-7-en-6-one (2); a rare seven-membered lactone B ring, (22E,24S)-ergosta-7,22-dien-3β,5α-diol-6,5-olide (3); and an α,β-unsaturated fatty acid, (Z)-3-methyl-9-oxodec-2-enoic acid (4) as well as five known compounds, 10-hydroxykahukuene B (5), pacifenol (6), dysidamide (7), 7,7,7-trichloro-3-hydroxy-2,2,6-trimethyl-4-(4,4,4-trichloro-3-methyl-1-oxobu-tylamino)-heptanoic acid methyl ester (8), and the primary metabolite 2’-deoxynucleoside thymidine (9), have been isolated from the Red Sea sponge Spongia sp. The stereoisomer of 3 was discovered in Ganoderma resinaceum, and metabolites 5 and 6, isolated previously from red algae, were characterized unprecedentedly in the sponge. Compounds 7 and 8 have not been found before in the genus Spongia. Compounds 1–9 were also assayed for cytotoxicity as well as antibacterial and anti-inflammatory activities.     

Metabolites with Anti-Inflammatory Activity from the Mangrove Endophytic Fungus Diaporthe sp. QYM12

One new diterpenoid, diaporpenoid A (1), two new sesquiterpenoids, diaporpenoids B–C (2,3) and three new α-pyrone derivatives, diaporpyrones A–C (4–6) were isolated from an MeOH extract obtained from cultures of the mangrove endophytic fungus Diaporthe sp. QYM12. Their structures were elucidated by extensive analysis of spectroscopic data. The absolute configurations were determined by electronic circular dichroism (ECD) calculations and a comparison of the specific rotation. Compound 1 had an unusual 5/10/5-fused tricyclic ring system. Compounds 1 and 4 showed potent anti-inflammatory activities by inhibiting the production of nitric oxide (NO) in lipopolysaccharide (LPS)-induced RAW264.7 cells with IC₅₀ values of 21.5 and 12.5 μM, respectively.     

紫外诱变热带微藻选育高油脂藻株

为选育高含油量微藻藻种,本试验以优势藻株La4-37为原材料,采用紫外线辐射法对其进行诱变处理,获得了296株藻株。利用尼罗红荧光检测法对获得的藻株进行荧光检测,筛选获得相对含油量最大的诱变藻株M077和M040。通过对诱变株生长及脂荧光强度动态跟踪发现,诱变株生长周期和油脂积累时期基本一样,当达到平稳期时,诱变株油脂积累能力均有较大提高,脂荧光强度分别是原始藻株的6.2倍和1.7倍。     

Neuroprotective Metabolites from Vietnamese Marine Derived Fungi of Aspergillus and Penicillium Genera

Low molecular weight secondary metabolites of marine fungi Aspergillus flocculosus, Aspergillus terreus and Penicillium sp. from Van Phong and Nha Trang Bays (Vietnam) were studied and a number of polyketides, bis-indole quinones and terpenoids were isolated. The structures of the isolated compounds were determined by 1D and 2D NMR and HR-ESI-MS techniques. Stereochemistry of some compounds was established based on ECD data. A chemical structure of asterriquinone F (6) was thoroughly described for the first time. Anthraquinone (13) was firstly obtained from a natural source. Neuroprotective influences of the isolated compounds against 6-OHDA, paraquat and rotenone toxicity were investigated. 4-Hydroxyscytalone (1), 4-hydroxy-6-dehydroxyscytalone (2) and demethylcitreoviranol (3) have shown significant increasing of paraquat- and rotenone-treated Neuro-2a cell viability and anti-ROS activity.     

铜绿金龟子肠道链霉菌Streptomyces sp. BCa1 菌体的抗菌成分研究

为从昆虫来源的放线菌次级代谢产物中寻找药物先导分子,对铜绿金龟子幼虫肠道链霉菌Streptomyces sp. BCa1菌丝体化学成分进行了研究。通过活性跟踪,从其菌丝体的氯仿甲醇萃取物中分离得到主要成分1。利用高分辨质谱、一维和二维核磁波谱技术,将该主要成分1鉴定为具有双重旋转对称结构的不饱和大环内酯类抗生素阿扎霉素（elaiophylin）,具有显著的抗金黄色葡萄球菌活性。该类化合物为首次从昆虫来源的放线菌中发现。     

海洋共生菌Aspergillus sp.HDf2新活性次生代谢产物研究(英文)

对紫海胆共生真菌Aspergillus sp.HDf2的次生代谢产物进行分离和鉴定。采用摇瓶液体发酵,运用柱层析等方法对其发酵液成分进行分离纯化,经波谱解析和质谱分析进行结构鉴定,并运用滤纸片法对化合物进行体外抗金黄色葡萄球菌的活性测试。结果从该真菌发酵产物中鉴定出2个secospiculisporic acid新类似物,分别为secospiculisporic acid B(1)和secospiculisporic acid C(2),其中化合物1具有弱抗菌活性,抑菌直径为9.2 mm(20 mg/mL)。首次对化合物1的NMR数据进行了归属,化合物2为secospiculisporic acid类的新化合物。     

芽胞杆菌次生代谢产物及其在土传病害防控中的应用研究进展

介绍了芽胞杆菌次生代谢产物及防控土传病害的国内外研究现状,包括芽胞杆菌拮抗和促生物质种类、作用机理等,以及生防菌的防控应用、根际定殖等内容,并根据目前存在的问题进行了未来研究方向和前景展望。