华泽兰根的化学成分及其体外抑菌活性研究北大核心CSCD

利用硅胶、Sephadex LH-20、HPLC等各种色谱分离技术,从华泽兰根的乙醇提取物中分离得到9个化合物,通过理化性质和NMR波谱数据对它们进行了结构鉴定,分别为:达玛二烯醇乙酸酯(1)、(2R,3S)-5-乙酰基-6-羟基-2-异丙烯基-3-乙氧基苯并二氢呋喃(2)、豆甾醇(3)、邻苯二甲酸二丁酯(4)、12,13-dihydroxyeuparin(5)、5-乙酰-6-羟基-2-异丙烯基苯并呋喃(6)、2,5-二乙酰基-6-羟基苯并呋喃(7)、ruscodibenzofuran(8)、2-乙酰-5-(1-炔丙基)-噻吩-3-O-β-D-吡喃葡萄糖苷(9)。化合物1、2、4和8为首次从该种植物中分离得到,其中2、4和8为首次从该属植物中分离得到。采用牛津杯法评价部分化合物对5种病原菌的抑菌活性,并用肉汤稀释法测定各自的MIC值,结果显示,测试化合物对5种菌具有不同程度的抑菌活性,其中,1、6和8对肺炎克雷伯菌有较强抑菌活性,MIC值分别为0.98、0.98μg/m L和0.49μg/m L,化合物7对大肠埃希菌显示较强抑菌活性(MIC≤3.91μg/m L),化合物1、2、6和7对铜绿假单胞菌有较强抑菌活性,MIC值均为7.81μg/m L,可见化合物1及苯并呋喃类化合物2、6、7、8为华泽兰根主要抑菌活性成分。     

华泽兰根的化学成分及其体外抑菌活性研究

利用硅胶、Sephadex LH-20、HPLC等各种色谱分离技术,从华泽兰根的乙醇提取物中分离得到9个化合物,通过理化性质和NMR波谱数据对它们进行了结构鉴定,分别为:达玛二烯醇乙酸酯(1)、(2R,3S)-5-乙酰基-6-羟基-2-异丙烯基-3-乙氧基苯并二氢呋喃(2)、豆甾醇(3)、邻苯二甲酸二丁酯(4)、12,13-dihydroxyeuparin(5)、5-乙酰-6-羟基-2-异丙烯基苯并呋喃(6)、2,5-二乙酰基-6-羟基苯并呋喃(7)、ruscodibenzofuran(8)、2-乙酰-5-(1-炔丙基)-噻吩-3-O-β-D-吡喃葡萄糖苷(9)。化合物1、2、4和8为首次从该种植物中分离得到,其中2、4和8为首次从该属植物中分离得到。采用牛津杯法评价部分化合物对5种病原菌的抑菌活性,并用肉汤稀释法测定各自的MIC值,结果显示,测试化合物对5种菌具有不同程度的抑菌活性,其中,1、6和8对肺炎克雷伯菌有较强抑菌活性,MIC值分别为0.98、0.98μg/m L和0.49μg/m L,化合物7对大肠埃希菌显示较强抑菌活性(MIC≤3.91μg/m L),化合物1、2、6和7对铜绿假单胞菌有较强抑菌活性,MIC值均为7.81μg/m L,可见化合物1及苯并呋喃类化合物2、6、7、8为华泽兰根主要抑菌活性成分。     

斑叶紫金牛化学成分的研究（Ⅰ）

采用95%乙醇提取,反复硅胶柱层析分离和光谱、波谱方法鉴定结构,从斑叶紫金牛(Ardisia punctataLindl.)中初步分离鉴定出7个化合物,2-甲基-5-[14(顺)-十九烯基]-1,3-间苯二酚(1),2-甲基-5-壬烷基-1,3-间苯二酚(2),3-0-[6'-O-palmitoyl-β-D-glucosyl-]-spinasta-7,22(23)-diene(3a),3-O-[6'-O-pahnitoyl]-β-D-sin-cosyl-pyranosyl stignmsterol(3b),岩白菜素(4),11-O-(4'-O-methylgalloyl)-bergenin(5),正二十四烷酸(6).所有化合物均为首次从该植物中获得,其中化合物2和6为首次从该属植物中分得.     

剑叶龙血树内生真菌Colletotrichum sp.B-152次生代谢产物研究CSCD

采用色谱技术和波谱学分析从剑叶龙血树内生真菌Colletotrichum sp.B-152的培养液和菌丝中,鉴定出了9个化合物:2-hydroxy-4-methyl-1-phenyl-3-pentanone(1)、4-methyl-1-phenyl-2,3-pentanediol(2)、胸腺嘧啶核苷(3)、腺嘌呤核苷(4)、(22 E,24 R)-ergosta-7,22-diene-3β,5α,6β-triol(5)、(4 E,8 E)-N-D-2′-hydroxypalmitoyl-1-O-β-D-glycopyranosyl-9-methyl-4,8-sphingadienine(6)、tuberosider(7)、(22 E,24 R)-5α,8α-epidioxyergosta-6,22-dien-3β-ol(8)、十七烷酸(9),其中化合物1作为天然产物首次报道,化合物2~4、6、7、9首次从刺盘孢属Colletotrichum真菌中分离得到。采用滤纸片扩散法对单体化合物的抑菌活性进行测定,9个化合物对至少一种指示菌表现出不同程度的抑制作用,其中化合物7和8表现出较为广谱的抑菌活性。     

酵母诱导欧洲花楸悬浮细胞的化学成分及抑菌活性

以酵母提取物(yeast extract,YE)作为外加诱导子对欧洲花楸悬浮细胞(Sorbus aucuparia suspension cell,SASC)产生生物胁迫作用并对胁迫环境下产生的悬浮细胞次生代谢产物进行分离鉴定及抑菌活性研究。运用正相硅胶、Sephadex LH-20、半制备型HPLC等色谱方法及现代波谱技术,从SASC甲醇提取物中分离鉴定了13个化合物,分别为:eriobofuran(1)、4,5-dihydroxy-3-methoxybiphenyl(2)、2'-hydroxyaucuparin(3)、aucuparin(4)、trans-cinnamic acid(5)、citrostadienol(6)、β-谷甾醇(7)、uvaol(8)、白桦脂酸(9)、tormentic acid(10)、alphitolic acid methyl ester(11)、fupenzic acid(12)、亚油酸(13)。其中,化合物5～13为首次从SASC中分离得到。选择化合物1～3、5、8和12对15种植物病原真菌进行抑菌活性测试,其中联苯类化合物1和2对苹果轮纹菌具有显著的抑制活性,MIC分别为3. 13和6. 25μg/m L。     

黄河三角洲土曲霉Aspergillus terreus OUCMDZ-1925中具抗菌活性的聚酮类天然产物

作者利用化学与生物活性相集成的筛选方法,从采自黄河三角洲地区——东营黄河口的梭鱼Chelon haematocheilus的内脏中分离鉴定了1株耐盐真菌土曲霉Aspergillus terreus OUCMDZ-1925,其发酵产物具有抗枯草芽孢杆菌活性。进一步采用色谱分离、波谱鉴定,从其固体发酵(大米培养基)中分离鉴定了5个化合物,即右旋丁内酯I(1)、丁内酯IV(2)、丁内酯II(3)、丁内酯III(4)和3,5,6-三甲基-2,4-二羟基苯甲酸甲酯(5)。并发现化合物1–3和5对金黄色葡萄球菌(ATCC51650)有强的抑菌活性(最小抑菌浓度均为0.31μg/mL,阳性对照环丙沙星的最小抑菌浓度为0.16μg/mL),化合物1和2对产气杆菌(ATCC13408)以及化合物1和3对枯草芽孢杆菌(ATCC93151)有中等的抑菌活性(最小抑菌浓度分别为6.25μg/mL和12.50μg/mL,阳性对照环丙沙星的最小抑菌浓度分别为1.25μg/mL和5.0μg/mL),化合物1–5对大肠杆菌(ATCC25922)以及化合物4对金黄色葡萄球菌(ATCC51650)有弱的抑制活性,且化合物1的产量高,达2.5g/kg,为其后续研究提供了新的药源。     

鹊肾树心材的化学成分及体外抗菌活性研究

本文研究鹊肾树Streblus asper心材的乙酸乙酯部分化学成分及体外抗菌活性.运用正相硅胶柱色谱层析,反相C-18柱色谱层析和Sephadex LH-20分高、纯化,最终得到8个化合物,经波谱解析并结合理化鉴定确定化合物结构为:银杏双黄酮(1)、异黄酮-4′-甲氧基-7-α-L-鼠李糖-(1→6)-β-D-葡萄糖(2)、鼠李柠檬素-3-O-β-D-半乳糖苷(3)、β-香树脂酮(4)、β-谷甾醇(5)、香革酸(6)、山俞酸(7)、二十六烷酸(8).除化合物5外,均为首次从该植物中提取到.此外研究了化合物1-4的抗菌活性,实验表明化合物2具有一定的抑菌活性.     

单叶蔓荆子黄酮类化学成分研究

采用MCI-Gel及硅胶等柱色谱法对云南西双版纳单叶蔓荆子的甲醇提取物的乙酸乙酯部分进行分离纯化,得到5个黄酮类似物,根据其理化性质,结合光谱技术(MS,NMR等)鉴定为紫花牡荆素(1)、3',5-二羟基-3,4',7-三甲氧基黄酮(2)、4',5-二羟基-3,6,7-三甲氧基黄酮(3)、牡荆葡基黄酮(4)和山奈酚-3-O-葡萄糖苷(5),化合物2～5为首次从该植物中分离得到.进行了抗羟基自由基氧化和抑菌活性的初步筛选实验,首次报道了化合物2、3的清除羟基自由基活性.     

北桑寄生内生真菌的分离及其次级代谢产物分析

首次对药用植物北桑寄生叶片中的内生真菌进行分离纯化,从中筛选出具有较高生物活性的菌株,鉴定此菌株并对其次级代谢产物进行初步分离。采用组织块法分离内生真菌,对其进行抗氧化活性和抑菌活性筛选;通过形态学和分子生物学方法鉴定其种属;运用柱色谱、重结晶等方法分离次级代谢产物,波谱学鉴定其结构。从北桑寄生叶片中分离纯化得到29株内生真菌,检测得到一株具有较高抗氧化和抑菌活性的菌株,鉴定为Alternaria alternata,从该菌次级代谢产物中首次分离得到3个单体化合物,分别为alternariol-5-O-methyl ether(1)、alternariol(2)、cis,cis-9,12-octadecadienoic acid(3)。化合物1和2具有较弱的抗氧化活性,化合物1和3表现出一定的抑菌活性。     

毛果鱼藤化学成分及生物活性研究

为了解毛果鱼藤(Derris eriocarpa How)藤茎和根中的生物活性成分,采用柱色谱技术,从其乙酸乙酯萃取部位分离得到6个化合物,分别鉴定为:高丽槐素(1)、美迪紫檀素(2)、大黄素(3)、松脂醇(4)、(6R,9R)9-hydroxy-4-megastigmen-3-one(5)、2-methoxygliricidol(6)。这些化合物均为首次从该植物中分离得到。体外抑菌、细胞毒抑制活性测试结果表明,化合物1、2对部分肿瘤细胞株及结核分枝杆菌(H37Rv)有明显抑制活性。     

Antioxidative oligostilbenes from Caragana sinica

Two new oligostilbenes, caragasinins A (5) and B (10), and eight known compounds, kobophenol A (1), (+)-α-viniferin (2), (+)-ampelopsin F (3), pallidol (4), (+)-isoampelopsin F (6), miyabenol C (7), carasinaurone (8) and caraphenol B (9) were isolated from the ethylacetate-soluble extract of the roots of Caragana sinica. The structures of the isolates were determined on the basis of extensive spectroscopic analysis including 1D, 2D NMR and HRESI-MS. These compounds were assessed for antioxidant activities. Caragasinin A (5), caraphenol B (9), and caragasinin B (10) showed moderate DPPH scavenging activity and lipid peroxidation inhibitory activities with IC(50) values ranging from 34.7±1.0 to 89.1±2.3μM.     

Molecular and biologic characteristics of Toxoplasma gondii isolates from wildlife in the United States

Toxoplasma gondii isolates can be grouped into 3 genetic lineages. Type I isolates are considered more virulent in outbred mice and have been isolated predominantly from clinical cases of human toxoplasmosis, whereas types II and III isolates are considered less virulent for mice and are found in humans and food animals. Little is known of genotypes of T. gondii isolates from wild animals. In the present report, genotypes of isolates of T. gondii from wildlife in the United States are described. Sera from wildlife were tested for antibodies to T. gondii with the modified agglutination test, and tissues from animals with titers of 1:25 (seropositive) were bioassayed in mice. Toxoplasma gondii was isolated from the hearts of 21 of 34 seropositive white-tailed deer (Odocoileus virginianus) from Mississippi and from 7 of 29 raccoons (Procyon lotor); 5 of 6 bobcats (Lynx rufus); and the gray fox (Urocyon cinereoargenteus), red fox (Vulpes vulpes), and coyote (Canis latrans) from Georgia. Toxoplasma gondii was also isolated from 7 of 10 seropositive black bears (Ursus americanus) from Pennsylvania by bioassay in cats. All 3 genotypes of T. gondii based on the SAG2 locus were circulating among wildlife.     

Mycotoxin Production by Fusarium Species Isolated from Bananas

The ability of Fusarium species isolated from bananas to produce mycotoxins was studied with 66 isolates of the following species: F. semitectum var. majus (8 isolates), F. camptoceras (3 isolates), a Fusarium sp. (3 isolates), F. moniliforme (16 isolates), F. proliferatum (9 isolates), F. subglutinans (3 isolates), F. solani (3 isolates), F. oxysporum (5 isolates), F. graminearum (7 isolates), F. dimerum (3 isolates), F. acuminatum (3 isolates), and F. equiseti (3 isolates). All isolates were cultured on autoclaved corn grains. Their toxicity to Artemia salina L. larvae was examined. Some of the toxic effects observed arose from the production of known mycotoxins that were determined by thin-layer chromatography, gas chromatography, or high-performance liquid chromatography. All F. camptoceras and Fusarium sp. isolates proved toxic to A. salina larvae; however, no specific toxic metabolites could be identified. This was also the case with eight isolates of F. moniliforme and three of F. proliferatum. The following mycotoxins were encountered in the corn culture extracts: fumonisin B(inf1) (40 to 2,900 (mu)g/g), fumonisin B(inf2) (150 to 320 (mu)g/g), moniliformin (10 to 1,670 (mu)g/g), zearalenone (5 to 470 (mu)g/g), (alpha)-zearalenol (5 to 10 (mu)g/g), deoxynivalenol (8 to 35 (mu)g/g), 3-acetyldeoxynivalenol (5 to 10 (mu)g/g), neosolaniol (50 to 180 (mu)g/g), and T-2 tetraol (5 to 15 (mu)g/g). Based on the results, additional compounds produced by the fungal isolates may play prominent roles in the toxic effects on larvae observed. This is the first reported study on the mycotoxin-producing abilities of Fusarium species that contaminate bananas.     

Two novel trimeric resveratrol derivatives from Cotylelobium lanceolatum

Two new resveratrol (= 5-[(E)-2-(4-hydroxyphenyl)ethenyl]benzene-1,3-diol) trimers, cotylelophenols A (1) and B (2), were isolated from the stem of Cotylelobium lanceolatum (Dipterocarpaceae), together with ten known resveratrol oligomers (3-12). The structures of the isolates were established on the basis of spectroscopic analyses, including a detailed NMR spectroscopic investigation of 1 under different conditions. Compound 1 is the first resveratrol trimer with a rearranged 4-hydroxyphenyl group. Four possible biogenetic pathways towards resveratrol oligomers are proposed (Scheme).     

Genetic diversity and molecular typing of Listeria monocytogenes in China

ABSTRACT: BACKGROUND: Listeria monocytogenes can cause invasive diseases in humans and farm animals and is frequently isolated from dairy products and poultry. Listeriosis is uncommon in China but L. monocytogenes has been isolated from foods and food processing environments in China. However little is known of genetic diversity of Chinese L. monocytogenes isolates and their relationships with global isolates. RESULTS: Two hundred and twelve isolates of L. monocytogenes from food sources from 12 provinces/cities in China were analysed by serotyping, Pulsed Field Gel Electrophoresis (PFGE) and Multi-locus Sequence Typing (MLST). The predominant serotypes are 1/2a, 1/2b and 1/2c accounting for 90.1% of the isolations. PFGE divided the isolates into 61 pulse types (PTs). Twenty nine PTs were represented by more than one isolates with PT GX6A16.0004 containing the most number of isolates. MLST differentiated the isolates into 36 STs, among which 15 were novel. The most common 3 STs were ST9 (29.1%), ST8 (10.7%) and ST87 (9.2%), accounting for 49.0% of the isolates. CONCLUSIONS: STs prevalent in other parts of the world are also prevalent in China including 7 STs (ST1-ST3, ST5, ST6, ST8, ST9) which caused maternal fetal infections or outbreaks, suggesting that these STs potentially can also cause severe human infections or outbreaks in China. Surveillance of these STs will provide important information for prevention of listeriosis. This study also enhances our understanding of genetic diversity of L. monocytogenes in China.     

New anticancer bastadin alkaloids from the sponge Dendrilla cactos

Two new bastadin alkaloids, bastadins-22 (1) and 23 (2), together with six known bastadins, bastadins-6 (3), -12 (4) (formerly basatadin-9), -14 (5), -15 (6), -16 (7), -19 (8), and a common steroid cholesterol were isolated from the sponge Dendrilla cactos. The structures of the isolates were established by the study of extensive spectroscopic analysis (1D and 2D NMR and MS data). Anticancer activity of the isolates has been carried out against Sup-T(1) cancer cells (T cell lymphoma).     

Isolation and identification of crude oil-degrading yeast strains from Khafji oil field,saud Arabia

Twenty five yeasts isolated were isolated from Khurais oil field in Saudi Arabia and assayed to evaluate their biodegradability. Only five isolates (namely, A1, A2, A3, A4 and A5) showed potential use of oil as sole carbon source. During incubation period, highest growth rate were recorded for A1, A2 and A3 isolates. Low growth distinguished A4 isolate; A5 isolate could not degrade oil.Spectrophotometrical analysis for four yeast isolates biodegradation activities indicated that, A1 isolate was superior for oil degradation (61%) comparing with A4 isolate which reflected lowest degradation % (33%). A2 and A3 isolates showed moderate biodegradation activity (56 and 51% respectively).D1/D2 domain of the 26S rRNA gene sequence was used as molecular marker to identify five yeast isolates. After comparing 26S rRNA gene sequences of five yeast isolates with highly similarity isolates, five yeast isolates (A1, A2, A3, A4 and A5)were submitted to database as Candida tropicalis (MW488263), Candida tropicalis (MW488264), Rhodotorula mucilaginosa (MW488265) and Rhodosporidium toruloides (MW488266) respectively. Using OXF1/ACR1 primer, specific lipase gene amplicon with 250 bp were detected with in all four yeast isolates.     

Dinorcassane Diterpenoid from Boesenbergia rotunda Rhizomes Collected in Lower Myanmar

A new dinorcassane diterpenoid, seikphoochinal A ( 1 ), and four known compounds, pinostrobin ( 2 ), 4′,7‐dimethylkaempferol ( 3 ), and galanals A ( 4 ) and B ( 5 ), were isolated from the chloroform‐soluble crude extract of wild type Boesenbergia rotunda rhizomes collected in Lower Myanmar. The chemical structures of these compounds were identified, using a combination of spectroscopic methods. The presence of the diterpenoids 1 , 4 , and 5 demonstrated the structural diversity of wild type B. rotunda. Among the isolates, compounds 4 and 5 exhibited significant antiproliferative activities against a small panel of human cancer cell lines, including lung (LK‐2, A549), stomach (ECC4), breast (MCF7), cervix (HeLa), and prostate (DU145).     

Trichodermaloids A–C,Cadinane Sesquiterpenes from a Marine Sponge Symbiotic Trichoderma sp. SM16 Fungus

Three new cadinane sesquiterpenes, trichodermaloids A ( 1 ), B ( 2 ), and C ( 5 ) were isolated from a symbiotic fungus Trichoderma sp. SM16 derived from the marine sponge Dysidea sp., together with three known ones, aspergilloid G ( 3 ), rhinomilisin E ( 4 ), and rhinomilisin G ( 6 ). The complete structures of three new compounds were determined by HR‐MS and NMR spectroscopic analyses coupled with ECD calculations. The absolute configurations of two known compounds ( 4 and 6 ) were determined for the first time. The six isolates were inactive as antibacterial agents. However, trichodermaloids A and B have shown cytotoxicity on human NCIH‐460 lung, NCIC‐H929 myeloma, and SW620 colorectal cancer cell lines with IC₅₀ values at the range of 6.8–12.7 μm .