植物内生真菌F4a次级代谢产物的分离鉴定以及降血糖、抗氧化活性的研究

研究植物内生真菌布雷青霉菌（Penicillium brefeldianum） F4a次级代谢产物的提取分离方法、结构鉴定及其降血糖和抗氧化活性。采用液体发酵培养,大孔吸附树脂HP20提取后,经硅胶柱色谱、Sephadex LH-20凝胶柱色谱、ODS反相开放柱色谱和高效液相色谱等手段进行分离,应用核磁共振等技术进行结构鉴定;采用紫外分光光度吸收法进行降血糖和抗氧化活性筛选。结果表明,分离得到6个化合物,分别鉴定为环（L-色氨酸-L-脯氨酸）（1）、3,3′-Methylenebis（4-hydroxy-6-methyl-2H-pyran-2-one）（2）、2-（2′S-Hydroxypropyl）-5-methyl-7-hydroxychromone（3）、染料木素（4）、大豆素（5）和苯酚（6）。化合物1和2具有一定的抗氧化活性,化合物4和5具有较强的抗氧化活性和降血糖活性。化合物2和3为首次从青霉属真菌中分离得到。化合物1和2的ABTS自由基清除活性为首次报道。     

小花清风藤的化学成分研究

利用Sephadex LH-20,硅胶柱色谱和硅胶制备薄层色谱等分离方法反复分离纯化,从小花清风藤（Sabia parviflora Wall．ex Roxb）中分离得到9个化合物,通过波谱数据分析分别鉴定它们为二十五烷酸（1）、木栓酮（2）、5-氧阿朴菲碱（3）、3-氧化齐墩果酸甲酯（4）、齐墩果酸（5）、羽扇豆-20（29）-烯-3-酮（6）、羽扇豆醇（7）、β-谷甾醇（8）、脱镁叶绿甲酯酸（9）。化合物2,6、7、9首次从该植物中分离得到。     

荔枝核化学成分的研究

利用硅胶柱色谱、聚酰胺柱色谱、制备薄层色谱等方法,从荔枝（Litchi chinensis Sonn．）核乙醇提取物中分离出9个化合物,根据理化性质和波谱分析鉴定了7个化合物,分别为胡萝卜苷（daucosterol,1）、原儿茶醛（protocatechuic aldehyde,2）、原儿茶酸（protoeatechuic acid,3）、表儿茶素（（-）-epicafichin,4）、procyanidin A2（5）、procyanidin A1（6）、芦丁（rulin,7）。化合物2,4-7为首次从荔枝核中分得,化合物2．4、5为首次从该属植物中分离得到。     

小花草玉梅化学成分研究

目的：研究银莲花属植物小花草玉梅的化学成分。方法：采用硅胶柱色谱,凝胶柱色谱,反相柱色谱并结合制备高效液相色谱等技术分离纯化单体化合物,并根据理化性质及光谱数据鉴定结构。结果：分离并鉴定了4个化合物,分别是常春藤皂苷元-28-O-β-D-吡喃葡萄糖酯苷（1）、3-O-β-D-吡喃葡萄糖-（1→2）-α-L-吡喃阿拉伯糖-齐墩果酸皂苷元-28-O-α-L-吡喃鼠李糖-（1→4）-β-D-吡喃葡萄糖-（1→6）-β-D-吡喃葡萄糖酯苷（2）、3-O-β-D-吡喃葡萄糖-（1→2）-α-L-吡喃阿拉伯糖-常春藤皂苷元-28-O-α-L-吡喃鼠李糖-（1→4）-β-D-吡喃葡萄糖-（1→6）-β-D-吡喃葡萄糖酯苷（3）和3-O-β-D-吡喃核糖-（1→3）-α-L-吡喃鼠李糖-（1→2）-α-L-吡喃阿拉伯糖-常春藤皂苷元-28-O-α-L-吡喃鼠李糖-（1→4）-β-D-吡喃葡萄糖-（1→6）-β-D-吡喃葡萄糖酯苷（4）。结论：化合物1为首次从银莲花属植物中分离得到,2-4为首次从小花草玉梅中分离得到。     

土木香化学成分的研究

采用硅胶柱色谱、制备薄层色谱、制备高效液相、葡聚糖凝胶SephadexLH-20等方法进行分离纯化,根据光谱数据进行结构鉴定。从乙醇提取物中分离得到了8个化合物,分别鉴定为：异土木香内酯（1）,11,13-二氢异土木香内酯（2）,土木香内酯（3）,β-谷甾醇（4）,3-hydroxy-11,13-dihydroisoalantolactone（5）,macrophyllilae-toneE（6）,HIS-12-en-18-H-3-O-β-D-glucopyranoside（7）,caffeic acid anhydride（8）。化合物7和8系首次从该属植物中分离得到。     

紫叶李果实的化学成分研究北大核心CSCD

采用硅胶、ODS和Sephadex LH-20柱色谱等方法对紫叶李果实95%乙醇提取物进行提取分离纯化,运用IR、UV、1H NMR、13C NMR、HMBC、HSQC等波谱学技术鉴定5个化合物：3-O-乙酰基原儿茶酸（1）、2（R）-羟基丁二酸-1-甲酯（2）、3,3′,4,4′-四羟基联苯（3）、β-胡萝卜苷（4）和槲皮素（5）。化合物1～4是首次从该植物中分离得到,其中化合物1为新天然产物,并且首次报道化合物1的1H NMR,13C NMR数据。对已分离的5个化合物进行了DPPH自由基清除实验,结果显示化合物3、5具有潜在的抗氧化活性。     

火麻仁的化学成分研究

采用硅胶柱色谱和葡聚糖凝胶LH-20,从火麻仁70％乙醇提取物的氯仿和乙酸乙酯萃取部位分离得到6个化合物。经理化鉴定和波谱方法鉴定方法确定为CannabsinA（1）．β-谷甾醇（2）、胡萝卜苷（3）、正二十四烷酸（4）、甘露醇（5）、棕榈酸（6）。     

刺玫果果肉石油醚层化学成分及胰脂酶和α-糖苷酶抑制活性研究北大核心CSCD

采用硅胶柱色谱、葡聚糖凝胶柱色谱等方法进行分离纯化,通过波谱数据进行结构鉴定,对石油醚层通过荧光检测法测定胰脂肪酶抑制活性,通过96微孔板法测定不同来源α-葡萄糖苷酶的抑制活性。从刺玫果果肉石油醚层分离得到12个化合物,分别鉴定为二十九烷（1）、α-生育酚（2）、邻苯二甲酸二乙酯（3）、邻苯二甲酸二丁酯（4）、β-谷甾醇（5）、α-香树脂醇（6）、乌苏醇（7）、白桦脂醇（8）、白桦脂酸（9）、19α-羟基乌苏酸（10）、胡萝卜苷（11）和麦芽糖（12）。化合物1~3、6~7和12首次从该植物中分离得到,石油醚层对胰脂肪酶和酵母菌来源的α-葡萄糖苷酶具有一定的抑制活性。     

紫花苜蓿化学成分的研究(英文)

为研究紫花苜蓿（Medicago scttiva L．）地上部位的化学成分,通过溶剂萃取、硅胶柱色谱、凝胶柱色谱分离纯化,从紫花苜蓿地上部分分离得到9个化合物,根据质谱和核磁共振数据鉴定为小檗碱（1）、大黄素（2）、大黄素8-O-β-D-葡萄糖苷（3）、soyαsαpogenol B-3-O-β-glcA（4）、邻羟基苯甲酸（5）、反式对羟基肉挂酸（6）、顺式对羟基肉桂酸（7）、正三十烷醇（8）和β-胡萝卜苷（9）。其中化合物1—4为首次从苜蓿属植物中分离得到。     

六妹羊肚菌的化学成分

以六妹羊肚菌Morchella sextelata为研究对象,对其子实体的化学成分进行研究。采用气相色谱-质谱联用技术（GC-MS）进行子实体芳香物和亲脂性提取物的化学成分分析,同时对其亲脂性提取物的抗氧化和抗菌活性进行了初步评价;采用正反相硅胶柱色谱、葡聚糖凝胶柱色谱等多种色谱分离方法进行化学成分的分离纯化,并通过核磁共振（NMR）、质谱（MS）等技术鉴定化合物结构。从六妹羊肚菌子实体的芳香物中共鉴定出26个化合物,辛-1-烯-3-醇（32.53%）、(E)-辛-2-烯醛（25.15%）和苯乙醛（12.31%）为主要成分;从六妹羊肚菌子实体的亲脂性提取物中共鉴定出14个化合物,亚油酸（77.80%）为主要成分;六妹羊肚菌亲脂性提取物仅显示出中等强度的抗氧化活性。从六妹羊肚菌子实体中共分离鉴定出14个化合物,包括7个甾体类化合物,其中化合物1、2、4、7、11、13和14为首次从羊肚菌属中分离得到。本研究首次对六妹羊肚菌的小分子化学成分进行了分析,对羊肚菌活性物质的阐明及进一步开发利用具有重要意义。     

Transglycosylation to ginseng saponins by cyclomaltodextrin glucanotransferases

Ten new alpha-glucosylginsenosides were found to be synthesized from dextrin and four ginsenosides, -Rb1, -Rc, -Re, and -Rg1, by the successive actions of B. stearothermophilus cyclomaltodextrin glucanotransferase and Rhizopus glucoamylase. Seven of them were isolated in the pure state by extraction with n-butanol saturated with water, silica gel column chromatography, and high pressure liquid chromatography, and identified as 3-O-[alpha-D-glcp-(1-->4)-beta-D-glcp-(1-->2)-beta-D-glcp]-20-O-[beta-D-glcp-(1-->6)-beta-D-glcp]-20(S)-protopanaxadiol, 3-O-[beta-D-glcp-(1-->2)-beta-D-glcp]-20-O-[alpha-D-glcp-(1-->4)-beta-D-glcp-(1-->6)-beta-D-glcp]-20(S)-protopanaxadiol, 3-O-[alpha-D-glcp-(1-->4)-beta-D-glcp-(1-->2)-beta-D-glcp]-20-O-[alpha-L-araf-(1-->6)-beta-D-glcp]-20(S)-protopanaxadiol, 3-O-[beta-D-glcp-(1-->2)-beta-D-glcp]-20-O-[(4G-alpha-D-glcp)-alpha-L-araf-(1-->6)-beta-D-glcp]-20(S)-protopanaxadiol, 6-O-[alpha-L-rhap-(1-->2)-beta-D-glcp]-20-O-[alpha-D-glcp-(1-->4)-beta-D-glcp]-20(S)-protopanaxatriol, 6-O-[alpha-D-glcp-(1-->4)-beta-D-glcp]-20-O-(beta-D-glcp)-20(S)-protopanaxatriol, and 6-O-[alpha-D-glcp-(1-->3)-beta-D-glcp]-20-O-(beta-D-glcp)-20(S)-protopanaxatriol, by spectroscopy (FAB-MS, IR, 1H-NMR and 13C-NMR) and hydrolysis products in 50% acetic acid. The bitterness of these alpha-glucosyl-ginsenosides was less than that of ginsenosides.     

Acylated protopanaxadiol-type ginsenosides from the root of Panax ginseng

Six new protopanaxadiol-type ginsenosides, named ginsenosides Ra(4) -Ra(9) (1-6, resp.), along with 14 known dammarane-type triterpene saponins, were isolated from the root of Panax ginseng, one of the most important Chinese medicinal herbs. The structures of the new compounds were determined by spectroscopic methods, including 1D- and 2D-NMR, HR-MS, and chemical transformation as (20S)- 3-O-{β-D-6-O-[(E)-but-2-enoyl]glucopyranosyl-(1→2)-β-D-glucopyranosyl}-20-O-[β-D-xylopyranosyl-(1→4)-α-L-arabinopyranosyl-(1→6)-β-D-glucopyranosyl]protopanaxadiol (1), (20S)-3-O-[β-D-6-O-acetylglucopyranosyl-(1→2)-β-D-glucopyranosyl]-20-O-[β-D-xylopyranosyl-(1→4)-α-L-arabinopyranosyl-(1→6)-β-D-glucopyranosyl]protopanaxadiol (2), (20S)-3-O-{β-D-6-O-[(E)-but-2-enoyl]glucopyranosyl-(1→2)-β-D-glucopyranosyl}-20-O-[β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyl]protopanaxadiol (3), (20S)-3-O-{β-D-6-O-[(E)-but-2-enoyl]glucopyranosyl-(1→2)-β-D-glucopyranosyl}-20-O-[α-L-arabinopyranosyl-(1→6)-β-D-glucopyranosyl]protopanaxadiol (4), (20S)-3-O-{β-D-4-O-[(E)-but-2-enoyl]glucopyranosyl-(1→2)-β-D-glucopyranosyl}-20-O-[α-L-arabinofuranosyl-(1→6)-β-D-glucopyranosyl]protopanaxadiol (5), (20S)-3-O-{β-D-6-O-[(E)-but-2-enoyl]glucopyranosyl-(1→2)-β-D-glucopyranosyl}-20-O-[α-L-arabinofuranosyl-(1→6)-β-D-glucopyranosyl]protopanaxadiol (6). The sugar moiety at C(3) of the aglycone of each new ginsenoside is butenoylated or acetylated.     

New pregnane glycosides from Brucea javanica and their antifeedant activity

Three new pregnane glycosides, 3-O-β-D-glucopyranosyl-(1→2)-α-L-arabinopyranosyl-(20R)-pregn-5-ene-3β,20-diol (1), 3-O-α-L-arabinopyranosyl-(20R)-pregn-5-ene-3β,20-diol-20-O-β-D-glucopyranoside (2), 3-O-α-L-arabinopyranosyl-(20R)-pregn-5-ene-3β,20-diol-20-O-β-D-glucopyranosyl-(1→2)-β-D-glucopyranoside (3) were isolated along with four known compounds, 4-7, from the leaves and stems of Brucea javanica. Their structures were determined by detailed analyses of 1D- and 2D-NMR spectroscopic data. All of the compounds isolated from Brucea javanica were tested for the antifeedant activities against the larva of Pieris rapae. Compounds 1, 3, and 5 showed significant antifeedant activities after 72 h incubation.     

De novo biosynthesis of arachidonic acid and 5,11,14-eicosatrienoic acid in the cricket Teleogryllus commodus

The de novo biosynthesis of 5,11,14-eicosatrienoic acid (5,11,14-20:3), arachidonic acid (20:4(n - 6] and eicosadienoic acid (20:2(n - 6] and the elongation/desaturation of linoleic acid (18:2(n - 6] to 20:4(n - 6) and alpha-linolenic acid (18:3(n - 3] to eicosapentaenoic acid (20:5(n - 3] were demonstrated in adult males of the field cricket Teleogryllus commodus. Sodium [1-14C]acetate, [1-14C]18:2(n - 6) and [1-14C]18:3(n - 3) were injected into adult male crickets and after an incubation period, the testes and remaining tissues were extracted and the methyl esters obtained from the phospholipid and triacylglycerol fractions were analyzed. After 5 days of daily injections of [1-14C]acetate, the methyl esters of the triene and tetraene fatty acids from the testicular phospholipid fraction were purified by AgNO3-TLC and HPLC and analyzed by GLC, radio-HPLC, and radio-GLC of ozonolysis products. The results demonstrate the de novo biosynthesis of 20:2(n - 6), 20:4(n - 6) and an isomer of 20:3(n - 6) with double bonds in the 5,11,14 positions. the elongation/desaturation of 18:2(n - 6) to 20:4(n - 6) and 18:3(n - 3) to 20:5(n - 3) was demonstrated by analysis of the methyl esters derived from the testicular phospholipid fraction by radio-HPLC after injecting crickets with radiolabeled substrates.     

Molecular organization of cholesterol in polyunsaturated phospholipid membranes: a solid state 2H NMR investigation.

We compared the molecular organization of equimolar [3alpha-2H1]cholesterol in 18:0-18:1PC (1-stearoyl-2-oleoylphosphatidylcholine), 18:0-22:6PC (1-stearoyl-2-docosahexaenoylphosphatidylcholine), 18:0-20:4PC (1-stearoyl-2-arachidonylphosphatidylcholine) and 20:4-20:4PC (1,2-diarachidonylphosphatidylcholine) bilayers by solid state 2H NMR. Essentially identical quadrupolar splittings (delta v(r) = 45 +/- 1 kHz) corresponding to the same molecular orientation characterized by tilt angle alpha0 = 16 +/- 1 degrees were measured in 18:0-18:1PC, 18:0-22:6PC and 18:0-20:4PC. A profound difference in molecular interaction with dipolyunsaturated 20:4-20:4PC, in contrast, is indicated for the sterol. Specifically, the tilt angle alpha0 = 22 +/- 1 degrees (derived from delta v(r) = 37 +/- 1 kHz) is greater and its membrane intercalation is only 15 mol%.     

4-1BBL enhances anti-tumor responses in the presence or absence of CD28 but CD28 is required for protective immunity against parental tumors

A20 is an aggressive BALB/c B cell lymphoma that, despite its expression of B7-2, rapidly forms tumors in syngeneic mice. We have generated A20 transfectants expressing elevated levels of B7-2 (A20/B7-2high) or 4-1BBL (A20/4-1BBL(low,mod,high)) and found that mice which were able to reject the A20/B7-2 or A20/4-1BBL transfectants were also resistant to subsequent systemic challenge with the parental cell line. To assess whether the effectiveness of 4-1BBL in enhancing anti-tumor immunogenicity was dependent on additional signals from B7-CD28 interaction, we injected the A20 variants into BALB/c CD28(-/-) mice. We found that CD28(-/-) mice were able to reject the A20/4-1BBL variants while A20/B7-2 cells formed tumors. However, when the A20/4-1BBL resistant CD28(-/-) mice were systemically challenged with the A20 parental line, tumors formed rapidly. Upon restimulation in vitro, splenocytes from A20/4-1BBL immunized CD28(+/+) mice were able to kill parental tumors whereas splenocytes from CD28(-/-) mice showed a reduction in CTL activity against A20 or A20/4-1BBL targets. Examination of cytokine production by the immunized animals indicated that the CD28(-/-) splenocytes secreted substantially less IL-2 as well as reduced levels of IFN-gamma compared with their CD28(+/+) counterparts. Thus, 4-1BBL expressing tumors are capable of priming CTL responses against 4-1BBL transfected as well as parental tumors in the absence of CD28. However, in the absence of CD28 signaling, the production of cytokines and particularly IL-2 was lower, resulting in a weaker CTL recall response and reduced ability to survive challenge with parental tumor.     

HP (2-20) derived from the amino terminal region of helicobacterpylori ribosomal protein L1 exerts its antifungal effects by damaging the plasma membranes of Candida albicans.

The fungicidal effects of the peptide HP (2-20). derived from the N-terminal sequence of Helicobacter pylori ribosomal protein L1 (RPL1). have been investigated. HP (2-20) displays a strong fungicidal activity against various fungi, without haemolytic activity against human erythrocyte cells, and the fungicidal activity is inhibited by Ca2+ and Mg2+ ions. In order to investigate the fungicidal mechanism(s) of HP (2-20). the amount of intracellular trehalose was measured in C. albicans. It was found that the amounts of intracellular trehalose were decreased when HP (2-20) was used. The action of the peptide against fungal cell membranes was further examined by the potassium-release test; HP (2-20) was found to increase the amount of K+ released from the cells. Furthermore, HP (2-20) caused significant morphological changes, as shown by scanning electron microscopy, and by testing the membrane disrupting activity using liposomes (phosphatidyl choline/cholesterol; 10: 1, w/w). Our results suggest that HP (2-20) may exert its antifungal activity by disrupting the structure of cell membranes, via pore formation or direct interaction with the lipid bilayers.     

Effect of copper sulfate on the immune response and susceptibility to Vibrio alginolyticus in the white shrimp Litopenaeus vannamei

White shrimp Litopenaeus vannamei (Boone) held in 35 per thousand seawater were challenged with Vibrio alginolyticus at a dose of 3 x 10(5) colony-forming units (cfu) shrimp(-1), and then placed in water containing concentrations of Cu2+ at 0 (control), 1, 5, 10 and 20 mg l(-1). Mortality of shrimp in 5, 10 and 20 mg l(-1) Cu2+ was significantly higher than those in 1 mg l(-1) Cu2+ and the control solution after 24-96 h. In another experiment, L. vannamei which had been exposed to control, 1, 5, 10 and 20 mg l(-1) Cu2+ for 24, 48 and 96 h were examined for THC (total haemocyte count), phenoloxidase activity, respiratory burst (release of superoxide anion), phagocytic activity and clearance efficiency to V. alginolyticus. Copper concentrations at 1 mg l(-1) or greater for 24h resulted in decreased THC, phenoloxidase activity, phagocytic activity and clearance efficiency, whereas copper concentration at 20 mg l(-1) caused significant increase in respiratory burst of L. vannamei. In conclusion, concentration of Cu2+ at 1 mg l(-1) or greater increased the susceptibility of L. vannamei to V. alginolyticus infection by a depression in immune ability. The release of superoxide anion by L. vannamei exposed to 20 mg l(-1) Cu2+ was considered to be cytotoxic to the host.     

Catabolism of rat growth hormone-releasing factor(1-29) amide in rat serum and liver.

Clinical and veterinary uses of growth hormone-releasing factor [GRF(1- 29)NH2] require the design of analogs that are resistant to proteolysis by serum and liver degrading enzymes. This study investigated rat GRF(1-29)NH2 processing in serum and liver homogenate by means of high pressure liquid chromatography (HPLC). Synthetic rGRF(1-29)NH2 (30 microM) was incubated (0-120 min, 37 degrees C) in serum (49 +/- 8 mg prot./ml). The rGRF(1-29)NH2 (10 microM) was also incubated (0-120 min, 37 degrees C) with liver homogenate (200 +/- 6 micrograms prot./ml). Time course studies of rGRF(1-29)NH2 disappearance showed apparent half-lives of 18 +/- 4 min and 13 +/- 3 min in serum and liver homogenate, respectively. This was accompanied by the appearance of degradation products that were all less hydrophobic than the native peptide. In the serum, two major metabolites were detected and isolated by preparative HPLC. Combined results of amino acid analysis, sequencing, and chromatography with synthetic homologs revealed the presence of rGRF(1-20)OH and (3-20)OH. A small amount of rGRF(12-29)NH2, coeluting with rGRF(3-20)OH, was also found by sequencing. In the liver, rGRF(1-18)OH, (3-18)OH, and (1-10)OH were identified. The peptide bond Ala2-Asp3 (DPP IV cleavage site) was hydrolyzed in both serum and liver. Other tissue-specific cleavage sites were Arg11-Arg12 and Arg20-Lys21 (trypsin-like cleavage site) in the serum, and Tyr10-Arg11 and Tyr18-Ala19 (chymotrypsin-like cleavage site) in the liver.(ABSTRACT TRUNCATED AT 250 WORDS)