土壤放线菌Streptomyces sp．2215代谢物的分离鉴定及抗肿瘤活性研究

土壤来源的放线菌Streptomyces sp.2215 经发酵罐发酵,培养液经乙酸乙酯提取,硅胶柱层析、C18反相色谱、Sephadex LH-20、及TLC 和HPLC分离纯化得到四个化合物,并通过理化性质,IR,FAB-MS,1H,13C NMR,1H-1HCOSY,HSQC,HMBC等鉴定为单亚砜棘霉素(monosulfoxide quinomycine,1)、棘霉素(echinomycin,2)、喹喔啉-2-羧酸(3)、十六烷酸(4).其中化合物1、2经MTT法测定体外对K562细胞具有抑制活性,其IC50值分别为34.0、1.5 ng/mL.     

Salinity-Induced Attenuation in Secondary Metabolites Profile and Herbicidal Potential of Brassica nigra L. on Anagallis arvensis L.

Studies on plant defense mechanisms in stressful conditions predict that plant cope up with increasing stress for survival. Under environmental stress plants interact with problems like competition and survival under resource constraints or utilization of these resources in production of secondary compounds. In this experiment, we examined the costs of defense by evaluating variation in production of secondary compounds of Brassica nigra grown in the saline (B1?=?100 mM NaCl and B2?=?150 mM NaCl) and control (C?=?0 mM) soils and impact of its extracts on weed Anagallis arvensis L. The main allelopathic compounds in Brassica were determined using gas chromatography–mass spectroscopy (GC–MS). The results indicated that A. arvensis was adversely affected by the aqueous extracts of B. nigra. These observations might be related to extracts induced oxidative stress indicated by superoxide (O₂^?) production through nitroblue tetrazolium, cell integrity by Evans blue staining, malondialdehyde estimation by Schiff reagent, lipid peroxidation, lignin deposition, and antioxidant enzyme activities assay. We observed that soil salinity reduced the phytotoxicity of aqueous extract and decreased its potential. The presence of different bioactive compounds improved the natural herbicidal properties of B. nigra and it can be used in various medicinal and agricultural practices.

     

滇牡丹内生真菌PR20的鉴定及次生代谢产物的研究

根据形态学特征和18S rDNA序列分析,将滇牡丹根中分离得到的内生真菌菌株PR20鉴定为高大毛壳Chaetomium elatum。利用柱色谱层析方法从该菌株的发酵产物中分离到5个化合物,通过理化性质及波谱数据分析,分别鉴定为7-羟基-4,6二甲基苯酞(1)、苔黑酚(2)、苔色酸(3)、间羟基苯甲酸(4)和次黄嘌呤核苷(5),以上化合物均为首次从滇牡丹内生真菌中分离获得。     

Elicitation Improves the Leaf Area,Enzymatic Activities,Antioxidant Activity and Content of Secondary Metabolites in Achillea millefolium L. Grown in the Field

Salicylic acid (SA) is a plant hormone that stimulates the growth and metabolism of plants, also acting as an abiotic elicitor. This study aimed to evaluate the effect of SA on leaf production, leaf area and synthesis of secondary compounds in yarrow plants. The experiments were conducted under field conditions in two consecutive years and f-received SA foliar applications (T1-control; T2-1.0 mmol L⁻¹ applications at 20, 60 and 100 days after planting (DAP) and T3-1.0 mmol L⁻¹ applications at 100 DAP during 3 days). The exogenous application of SA resulted in increases in leaf area (total and specific), number of leaves and leaf mass ratio of yarrow plants, polyphenolic compounds, phenylalanine ammonia-lyase and chalcone synthase enzymes and the antioxidant activity of the plant extract. The HPLC–DAD–MS/MS analysis of phenolic compounds revealed increases in the amounts of quinic acid and rutin. The results of this research lead us to affirm that SA exerted both the hormonal effect on number of leaves and leaf area, and also acted as eliciting substance.

     

地衣次生代谢产物及其生物活性研究进展

地衣是一类独特的生物有机体,其体内合成了多种特殊的次生代谢产物,主要为缩酚酸、缩酚酸环醚、缩酚酮、二苯并呋喃等类化合物。这些次生代谢产物具有多样的生物活性,包括抗氧化、抗辐射、抗菌、抗病毒、抗肿瘤、植物生长抑制和昆虫拒食等活性。本文对近40年来有关地衣化学及生物活性方面的研究进行综述,为地衣资源的进一步研究和开发提供参考。     

Tissue-Specific Distribution of Secondary Metabolites in Rapeseed (Brassica napus L.)

Four different parts, hypocotyl and radicle (HR), inner cotyledon (IC), outer cotyledon (OC), seed coat and endosperm (SE), were sampled from mature rapeseed (Brassica napus L.) by laser microdissection. Subsequently, major secondary metabolites, glucosinolates and sinapine, as well as three minor ones, a cyclic spermidine conjugate and two flavonoids, representing different compound categories, were qualified and quantified in dissected samples by high-performance liquid chromatography with diode array detection and mass spectrometry. No qualitative and quantitative difference of glucosinolates and sinapine was detected in embryo tissues (HR, IC and OC). On the other hand, the three minor compounds were observed to be distributed unevenly in different rapeseed tissues. The hypothetic biological functions of the distribution patterns of different secondary metabolites in rapeseed are discussed.     

江西青霉的次生代谢产物研究

江西青霉是药用江西虫草的无性型,本文对江西青霉发酵菌丝体甲醇提取物的正丁醇萃取部位运用反复色谱层析进行了系统的分离纯化,得到了6个化合物。经波谱解析,并结合理化鉴定,确定这6个化合物结构为尿嘧啶(1)2、’-脱氧尿嘧啶核苷(2)、腺嘌呤(3)、腺苷(4)、L-焦谷氨酸甲酯(5)和2’-甲氧基腺苷(6)。其中化合物2、5和6为首次从虫草属中分离获得的化合物。     

绿茶水提物中主要次生代谢产物的分离纯化与结构鉴定

根据加工过程的不同,茶叶可以分为不发酵茶、半发酵茶、全发酵茶。绿茶是典型的不发酵茶,加工过程中,由于高温湿热作用,破坏了茶叶中酶的活性,阻止了茶叶中主要成分的酶性氧化,因此绿茶中含有丰富的次生代谢产物,这些物质不仅赋予了茶叶独有的色、香、味品质,而且与人体健康密切相关。为了建立绿茶水提物中主要次生代谢产物的化合物标准库,本文利用Amberlite XAD-2大孔吸附树脂、硅胶柱色谱及Sephadex LH-20凝胶柱色谱分离技术对绿茶水提物中的主要次生代谢产物进行了系统的分离纯化,采用质谱、核磁共振波谱对分离得到的化合物进行了结构鉴定。从绿茶的水提物中分离鉴定了8个化合物,分别是咖啡碱、儿茶素没食子酸酯、表儿茶素、3,5-二羟基-4-甲氧基苯甲酸、山柰酚-3-葡萄糖苷、没食子儿茶素没食子酸酯、儿茶素和没食子酸。     

海洋真菌Fusarium sp.次级代谢产物的研究

采用硅胶柱色谱、Sephadex LH-20凝胶柱色谱、开放ODS柱色谱以及HPLC等方法从海洋真菌Fusarium sp.的菌丝体中分离得到5个化合物,通过波谱数据及理化性质分别鉴定为3β,15β-二羟基-(22E,24R)-麦角甾-5,8(14),22-三烯-7-酮(1)、3β,5α,9α-三羟基-(22E,24R)-麦角甾-7,22-二烯-6-酮(2)、(22E,24R)-麦角甾-7,22-二烯-3β,5α,6β-三醇(3)、5α,8α-过氧-(22E,24R)-麦角甾-6,22-二烯-3β-醇(4)和丁二酸(5).其中化合物1和2首次从该属真菌中分离得到.     

Regeneration of plantlets in Sapindus trifoiatus L

Continuous production of healthy plantlets of Sapindus trifoliatus L. was achieved via somatic embryos from long term cultures of an embryogenic mass (EM). A highly embryogenic culture of S. trifoliatus L. was obtained by recurrent embryogenesis from somatic embryos cultured on Murashige and Skoog's (MS) medium supplemented with kinetin (2.3 microM) and benzyladenine (8.8 microM). The cultures could be maintained without reduction of embryogenic competence for more than 20 months by subculture at 4 week intervals. About 90% mature somatic embryos on transfer to basal MS medium, germinated to plantlets, of which more than 70% survived when transferred to a sand and soil mixture in green house.     

Identification of Gene-Specific Polymorphisms and Association with Capsaicin Pathway Metabolites in Capsicum annuum L. Collections

Pepper (Capsicum annuum L.) is an economically important crop with added nutritional value. Production of capsaicin is an important quantitative trait with high environmental variance, so the development of markers regulating capsaicinoid accumulation is important for pepper breeding programs. In this study, we performed association mapping at the gene level to identify single nucleotide polymorphisms (SNPs) associated with capsaicin pathway metabolites in a diverse Capsicum annuum collection during two seasons. The genes Pun1, CCR, KAS and HCT were sequenced and matched with the whole-genome sequence draft of pepper to identify SNP locations and for further characterization. The identified SNPs for each gene underwent candidate gene association mapping. Association mapping results revealed Pun1 as a key regulator of major metabolites in the capsaicin pathway mainly affecting capsaicinoids and precursors for acyl moieties of capsaicinoids. Six different SNPs in the promoter sequence of Pun1 were found associated with capsaicin in plants from both seasons. Our results support that CCR is an important control point for the flux of p-coumaric acid to specific biosynthesis pathways. KAS was found to regulate the major precursors for acyl moieties of capsaicinoids and may play a key role in capsaicinoid production. Candidate gene association mapping of Pun1 suggested that the accumulation of capsaicinoids depends on the expression of Pun1, as revealed by the most important associated SNPs found in the promoter region of Pun1.     

Proteomic and Metabolomic Analyses Reveal Contrasting Anti-Inflammatory Effects of an Extract of Mucor Racemosus Secondary Metabolites Compared to Dexamethasone

Classical drug assays are often confined to single molecules and targeting single pathways. However, it is also desirable to investigate the effects of complex mixtures on complex systems such as living cells including the natural multitude of signalling pathways. Evidence based on herbal medicine has motivated us to investigate potential beneficial health effects of Mucor racemosus (M rac) extracts. Secondary metabolites of M rac were collected using a good-manufacturing process (GMP) approved production line and a validated manufacturing process, in order to obtain a stable product termed SyCircue (National Drug Code USA: 10424–102). Toxicological studies confirmed that this product does not contain mycotoxins and is non-genotoxic. Potential effects on inflammatory processes were investigated by treating stimulated cells with M rac extracts and the effects were compared to the standard anti-inflammatory drug dexamethasone on the levels of the proteome and metabolome. Using 2D-PAGE, slight anti-inflammatory effects were observed in primary white blood mononuclear cells, which were more pronounced in primary human umbilical vein endothelial cells (HUVECs). Proteome profiling based on nLC-MS/MS analysis of tryptic digests revealed inhibitory effects of M rac extracts on pro-inflammatory cytoplasmic mediators and secreted cytokines and chemokines in these endothelial cells. This finding was confirmed using targeted proteomics, here treatment of stimulated cells with M rac extracts down-regulated the secretion of IL-6, IL-8, CXCL5 and GROA significantly. Finally, the modulating effects of M rac on HUVECs were also confirmed on the level of the metabolome. Several metabolites displayed significant concentration changes upon treatment of inflammatory activated HUVECs with the M rac extract, including spermine and lysophosphatidylcholine acyl C18:0 and sphingomyelin C26:1, while the bulk of measured metabolites remained unaffected. Interestingly, the effects of M rac treatment on lipids were orthogonal to the effect of dexamethasone underlining differences in the overall mode of action.     

Organic Matrix and Secondary Metabolites in Nacre

Marine Biotechnology - Nacre, also called mother-of-pearl, is a naturally occurring biomineral, largely studied by chemists, structural biologists, and physicists to understand its outstanding and...     

链霉菌YIM 245次生代谢产物的研究

利用多种柱色谱层析方法从来自非洲特有动物之一长颈鹿(Giraffa camelopardalisc)的粪便链霉菌YIM245的发酵产物中分离得到7个化合物,通过理化性质及波谱数据分析,分别鉴定为2'-脱氧胞嘧啶核苷(1)、2’-脱氧胸苷(2)、2’-脱氧尿苷(3)、2’-脱氧腺苷(4)、菜油甾醇(5)、大豆素(6)和邻氨基苯甲酸(7)。应用96孔板法测定了化合物对5种病原指示菌的最低抑制浓度(MIC),结果表明该7个化合物均显示较弱的抗菌活性。     

Effect of NaCl Salinity on Somatic Embryo Development in Sapindus trifoliatus L.

The effect of NaCl salinity on growth and development of somaticembryos of Sapindus trifoliatus L. was examined. Incorporationof 25 and 50 mol m^–3 NaCl into the medium greatly increasedthe growth and development of somatic embryos and both theseconcentrations favoured the production of secondary embryoids.However, supplementation of 100 mol m^–3 NaCl to the mediumdid not have any significant effect on the growth and developmentof somatic embryos. On the other hand, the culturing of proembryostructures in medium containing 200 mol m^–3 NaCl resultedin complete death within 7 d of salt exposure. Analysis of somatic embryos revealed that, upon salinization,they accumulated Na⁺ and Cl^– in significant amounts butthe content of Na⁺ was much less compared to that of Cl^–.Addition of NaCl (up to 50 mol m^–3) in the medium resultedin a considerable increase in the K⁺ content of somatic embryos.The content of proline in somatic embryos, however, increasedsubstantially in response to salinization. The amount of freesterols, steryl glycosides, steryl esters, and phospholipidsalso rose to higher values in salt-affected somatic embryos.The results suggest that somatic embryos of S. trifoliatus cantolerate concentrations of NaCl up to 100 mol m^–3 withoutaffecting growth and that they have sufficient cellular mechanismsto tolerate salinity at relatively high levels. Key words: Salinity, somatic embryo, sterols, phospholipids     

放线菌次生代谢产物合成基因组研究

简述放线菌全基因组研究概况,次生代谢产物合成基因组研究涉及的问题;重点介绍聚酮类化合物合成基因组的结构和功能;如何利用基因组筛选程序,筛选具有生物活性次生代谢产物合成基因簇的产生菌,作为新药发现的一种手段。     

海洋沉积环境来源真菌次生代谢产物的研究

海洋沉积环境复杂多样,微生物往往进化形成与其环境相适应的代谢系统.真菌作为海洋沉积环境中的重要微生物,它们的次生代谢产物结构出新率高、生物活性显著,是开发海洋先导药物的新兴资源.本文综述了1995-2011年间发表的200个海洋沉积环境真菌次生代谢产物,其来源菌株广泛分布在真菌16个属,主要集中在Penicillium属(30％)、Aspergillus属(19％)、Spicaria属(18％)和Trichoderma属(13％);其结构类型包括生物碱类(86个)、萜类(42个)、聚酮类(42个)、肽类(15个)、甾体类(5个)、脑苷脂类(4个)和其他类(6个),活性研究主要集中在细胞毒性和抗菌等方面.     

次生代谢产物与植物抗病防御反应

次生代谢产物是由植物次生代谢产生的许多结构不同的小分子有机化合物,它们广泛参与植物的生长、发育、防御等生理过程。次生代谢产物在植物的抗病防御反应中发挥着重要作用,可以作为生化壁垒防御病原物侵染,还可以作为信号物质参与植物的抗病反应;在植物与病原物互作中,植物合成新的抗菌物质植保素,原有的抗菌物质也会增加。植物次生代谢产物的积累受到病原物、发育,环境等多种因素的调节。本文重点介绍次生代谢产物在植物抗病防御中的相关作用以及影响其合成的各种因素。