超临界CO2萃取结合高速逆流色谱分离八角茴香精油中的化学成分

建立了超临界CO2提取,高速逆流色谱分离纯化八角茴香中精油的分离方法.首先利用超临界CO2提取八角茴香中的精油,萃取压力为25 MPa,萃取温度为35℃.1.3 g粗提物经高速逆流色谱分离,两相溶剂体系为正己烷-乙酸乙酯-甲醇-水(体积比1:0.2:1:0.1),一次分离出3种化合物,经EI-MS鉴定为茴香醛10.3 ...     

超临界CO_2萃取结合高速逆流色谱分离八角茴香精油中的化学成分(英文)

建立了超临界CO2提取,高速逆流色谱分离纯化八角茴香中精油的分离方法。首先利用超临界CO2提取八角茴香中的精油,萃取压力为25 MPa,萃取温度为35℃。1.3 g粗提物经高速逆流色谱分离,两相溶剂体系为正己烷-乙酸乙酯-甲醇-水(体积比1∶0.2∶1∶0.1),一次分离出3种化合物,经EI-MS鉴定为茴香醛10.3 mg、异丁香酚甲醚7.1 mg和反式-茴香脑636.5 mg,纯度分别为98.9%、96.8%和99.7%。     

楸树叶中抗氧化活性成分的分离和鉴定

前期研究发现,楸树叶粗提物的乙酸乙酯萃取相具有较强的抗氧化活性。为了进一步明确其抗氧化活性成分,以硅胶柱色谱结合清除 DPPH自由基法,寻找抗氧化能力较强的组分,并利用半制备液相色谱对该组分进行分离、纯化,以清除 DPPH自由基、还原力和清除 ABTS自由基能力作为考察指标,根据理化性质及光谱数据鉴定化合物。结果从楸树叶粗提物的乙酸乙酯萃取相中分离得到了2个化合物,分别为木犀草素(1)和芹菜素(2)。化合物1的抗氧化活性强于BHT和化合物2;化合物1清除DPPH自由基、还原力及清除ABTS自由基的IC50值分别为23.89,29.77和43.47μg mL -1;化合物1的抗氧化活性强于化合物2,主要因其在黄酮类化合物母核的 B环上具有邻二酚羟基结构。木犀草素和芹菜素2个化合物首次从楸树叶中分离得到。     

混合发酵次级代谢产物的研究

把混合发酵技术应用于分离自南海红树植物的2株内生海洋真菌(菌株编号为1924#和3893#)的培养,其发酵液乙酸乙酯粗提物表现出明显的杀棉铃虫(Heliothisarmigera Hühner)和中华鳋(Sinergasilus spp.)的活性。从该粗提物分离到2个纯培养未能得到的次级代谢产物A和B,经波谱分析分别鉴定它们为2-甲基水杨酸(A)和环(苯丙-苯丙)二肽(B)。其中优势代谢产物A是粗提物具有杀虫活性的主要原因。     

油茶蒲提取物的抗氧化活性

以油茶蒲粗提物为原料,将其溶于水后用不同的有机溶剂分级萃取,得到乙酸乙酯相、正丁醇相及水相。应用Folin-Ciocalteau法测定粗提物及分级萃取各相的总酚含量;同时应用DPPH法、TEAC法、FRAP法和全血体系总抗氧化能力(T-AOC法),以抗坏血酸(Vc)为阳性对照分别测定粗提物及分级萃取各相的抗氧化能力。结果表明:油茶蒲提取物具有较强的抗氧化能力,应用4种方法测定的结果一致,抗氧化能力强弱为:乙酸乙酯相>正丁醇相>粗提物>水相,总酚含量与抗氧化能力间存在较好的相关性。     

山核桃外果皮中的抑菌活性成分

用不同溶剂对山核桃外果皮甲醇浸膏进行萃取分离,得石油醚相、氯仿相、乙酸乙酯相、正丁醇相,以番茄早疫病菌、苹果腐烂病菌、小麦赤霉病菌、水稻纹枯病菌、黄瓜菌核病菌等5种病菌进行抑菌活性试验.结果表明:正丁醇相抑菌活性最强,氯仿相和石油醚相次之,乙酸乙酯相最弱.对氯仿相进行初步分离,得到7个单体化合物:乔松酮,黄卡瓦胡椒素,5-羟基-4',7-二甲氧基黄酮,5-羟基-2-甲氧基-1,4-萘醌,5-羟基-6,7-二甲氧基黄烷酮,乔松素,β-谷甾醇,均为首次从山核桃中分离得到,它们对玉米大斑病菌和水稻稻瘟病菌孢子萌发均有不同程度的抑制作用.     

臭蒿抗菌成分的分离和鉴定

采用硅胶柱层析法对臭蒿粗提物进行分离纯化,利用孢子萌发法对抗菌流分进行活性评价,采用高效液相色谱-质谱联用技术(HPLC-MS)分析抗菌流分的物质组成。结果显示:臭蒿粗提物分离纯化得到13种流分(Fr.1~Fr.13),其中流分Fr.5抗菌活性最好,对流分Fr.5进一步硅胶柱层析分离得到4种流分(Fr.5.1~Fr.5.4)。臭蒿粗提物对烟草链格孢菌孢子的EC50为5.04 g/L,流分Fr.5.2的EC50为0.57 g/L。LC-MS分析出流分Fr.5.2主要由去氧双羟基蒿甲醚(17.00%)、去氧双氢青蒿素(43.65%)、去氧青蒿素(16.15%)组成。以双氢青蒿素为标准品,测得流分Fr.5.2中双氢青蒿素的质量分数为40.95%,双氢青蒿素对烟草链格孢菌孢子的EC50为2.70 g/L,表明流分Fr.5.2中主要抗菌物质为青蒿素衍生物。     

麻疯树柄细蛾交尾行为及雄虫对性信息素粗提物的触角电位反应

在(25±1)℃、光周期16L:8D条件下研究麻疯树柄细蛾成虫的交尾行为、交尾节律及雄虫对性信息素粗提物的触角电位反应。结果表明:无论雌雄,成虫1日龄均可交尾,在1日龄时达到最高交尾率(70.12%),随着日龄的增加,交尾率降低,最低交尾率仅为5.81%,但交尾持续时间从89.33min增加到171.67min;在不同光照强度下,不同日龄成虫均能交尾,随着光照强度的增加,1日龄成虫交尾率从53.33%增加到69.40%;不同光强对4,5日龄成虫交尾持续时间影响不大;雄虫对性信息素粗提物的触角电位反应表明:在正己烷、正戊烷、二氯甲烷和乙醚4种溶剂中,正己烷是提取性信息素效果最好的溶剂;随着雄蛾日龄的增加,其对性信息素粗提物的反应逐渐下降;腺体提取比空气提取效果好;雄蛾对性信息素粗提物的反应最低浓度为10-3FE·(10μL)-1。     

日本落叶松新鲜松针的化学成分及其抗氧化活性研究

研究了日本落叶松新鲜松针的化学成分及其抗氧化活性.采用Sephadex LH-20柱色谱及薄层色谱等方法进行分离,从其95%乙醇提取物乙酸乙酯溶性部分中分到7种化合物,经波谱分析及理化性质化合物分别鉴定为:儿茶素(1)、表儿茶素(2)、没食子儿茶素(3)、异鼠李素-3-O-葡萄糖苷(4)、紫云英苷(5)、2"-O-鼠李糖牡荆黄苷(6)和cedrusin (7).7种化合物均首次从该植物中分得.经DPPH试验,测定了核酸溶性部分、二氯甲烷溶性部分、乙酸乙酯溶性部分、水溶性部分、粗提物及分得化合物的抗氧化活性.其中乙酸乙酯溶性部分及化合物1～3具有很强的抗氧化活性.     

雷公藤粗提物对卫矛尺蠖生物活性的影响

以4龄卫矛尺蠖为试虫,以取食量、虫体质量增长率、拒食率及死亡率为指标,用非选择性取食法及小叶碟添加法,测定乙醇、稀氨水两种溶剂浸提的雷公藤根皮粉浸提物的杀虫活性.结果表明:不同浓度的两种溶剂其粗提物对试虫均有拒食、毒杀及抑制生长发育的作用,且这种作用随其体积质量的增大而明显;但乙醇粗提物对试虫的作用比稀氨水浸提液的显著,乙醇粗提物的拒食中浓度AFC50为277.33 mg·L-1,毒杀中浓度LC50为116.41 mg·L-1,而稀氨水浸提液的拒食中浓度AFC50为383.97 mg·L-1,毒杀中浓度LC50为314.96 mg·L-1.     

红树林植物来源内生真菌构巢曲霉MA143次级代谢产物的分离与结构鉴定

以红树林植物来源内生真菌构巢曲霉MA143为研究对象,对其ICI培养基发酵粗提物的化学成分进行初步研究,以期从红树林植物中分离得到具有显著生物活性的新化合物,用于如抗肿瘤、抗真菌等医药用途。采用萃取法、硅胶柱层析、Sephadex LH-20凝胶柱层析、RP-18反相柱层析等技术从中分离纯化得到了3个化合物。结合碳谱(13C-NMR)、氢谱(1HNMR)、质谱(ESI-MS)等波谱学技术及相关数据库检索鉴定出这3个化合物分别为:sterigmatocystin、Versicolorin A、Averufanin。红树林植物开发新型生物活性物质的潜能不可低估,开发其药物价值,发挥其经济效益与生态效益,促进海岸居民对其加以保护和种植,具有非常重要的现实意义。     

乙酸乙酯混合溶剂精制塔拉单宁工艺研究

用乙酸乙酯萃取精制粗塔拉单宁,粗单宁、水、乙酸乙酯之比1∶1.5∶4(g∶mL∶mL),60℃下萃取30 min,其单宁得率为40.2%,单宁纯度80.4%,得率与纯度均偏低。用乙酸乙酯二次萃取其残留水相得率也偏低。对粗制的塔拉单宁用乙酸乙酯与S溶剂(体积比4∶1)混合溶剂进行精制,其最佳工艺条件是:料液比为m(粗单宁)∶V(水)∶V(混合溶剂)1∶1.5∶5(g∶mL∶mL),萃取温度60℃,萃取时间30 min。在该工艺条件下产品得率68.2%,单宁纯度86.0%,单宁提取率87.7%,得率和纯度都有提高。     

大孔树脂ADS-7分离纯化多穗柯黄酮工艺研究

采用大孔树脂ADS-7分离纯化多穗柯黄酮粗提物(CE),对主要工艺条件进行了研究。得出最佳工艺条件为:将CE先配成10%(体积分数)CE溶液,10?溶液体积与树脂质量比值(mL∶g)略大于3、在中性pH值下静态吸附2 h,再以3倍装柱体积(1 500 mL)的80%(体积分数)乙醇、每小时1倍装柱体积流速进行动态洗脱。该工艺条件得到的纯化产物中黄酮的质量分数由粗提物中的40%提高到纯化产物的88%,得率为91%。     

Isolation and characterization of a germination inhibitor from leaves of Empetrum hermaphroditum hagerup

An extract of Empetrum hermaphroditum Hagerup leaves was examined for germination inhibitors using an assay based on germination of Populus tremula L. seeds. The substances were extracted in water and purified by solvent partitioning. The acidic ethyl acetate fraction, containing the major part of the inhibitory activity was purified by reversed‐phase high‐performance liquid chromatography. Two zones of inhibitory activity were detected, combined and further purified by normal‐phase HPLC. One major zone of inhibitory activity was thereafter detected and the substance in this fraction was crystallized and identified by nuclear magnetic resonance and gas chromatography‐mass spectrometry as 5‐methoxy‐3,3´‐dihydroxy‐dihydrostilbene or batatasin III. Ca. 100 mg of the substance was then, by sequential HPLC, isolated in crystalline form from E. hermaphroditum leaves. The inhibitory activity of the pure substance was compared with a crude water extract of E. hermaphroditum leaves. It was concluded that the pure substance exhibited ca. 28 % of the inhibitory activity of the crude extract. The difference in inhibitory activity might be explained by the presence of a glucosidic conjugate of 5‐methoxy‐3,3´‐dihydroxy‐dihydrostilbene in the crude extract.     

Effect of Mahonia aquifolium stem bark crude extract and one of its polysaccharide components on production of IL-8.

The crude hydroalcoholic extract of Mahonia aquifolium stem bark and a polysaccharide isolated from the extract were tested for their activity on interleukin-8 (IL-8) production by human monocytic cell line THP-1. The crude extract partly inhibited the IL-8 spontaneous production after 48-h treatment of the cells, while the polysaccharide was found to be a potent inducer of IL-8 production.     

树脂吸附法分离高纯茶多酚新工艺研究

研究了树脂吸附法分离纯化茶多酚的绿色工艺。浸提低品位茶叶得到的浸提液，乘热粗沙沙滤，调pH值至1．5，使色素、咖啡因和大分子物质得到预分离，然后细沙沙滤、上AB-8树脂进行吸附，依次用蒸馏水和pH值为2-4的5％的乙醇溶液洗脱处理，洗脱剂为质量分数60％的乙醇，洗脱液喷雾干燥得到茶多酚产品，纯度可达90．22％。     

Anti-nociceptive activity of the aqueous extract of Erythrina velutina leaves

Anti-nociceptive and anti-oedematogenic effects of the aqueous extract from the leaves of Erythrina velutina were tested through experimental models of nociception in mice and paw oedema induced by carrageenin in rats. The extract (300 and 600 mg/kg) did not change the carrageenin-induced paw oedema. In the hot plate test the extract also did not alter the latency time for mice liking the rear paws. Moreover, the extract (600 mg/kg) decreased by 96.5% the paw liking time in the second phase of the formalin test. This effect was antagonized by naloxone (5 mg/kg). In the acetic acid-induced writhing test, the extract (300 and 600 mg/kg) reduced the number of writhing by 88.8% and 96.4%, respectively. Our present results demonstrated that the crude extract from the leaves of E. velutina has anti-nociceptive but not anti-oedematogenic properties.     

Potent antiviral flavone glycosides from Ficus benjamina leaves

Crude ethanol extracts from Ficus benjamina leaves strongly inhibit Herpes Simplex Virus 1 and 2 (HSV-1/2) as well as Varicella Zoster Virus (VZV) cell infection in vitro. Bioassay-guided fractionation of the crude extract demonstrated that the most efficient inhibition of HSV-1 and HSV-2 was obtained with the flavonoid fraction. The present study was aimed to further isolate, purify and identify substances with potent antiviral activity from the flavonoid fraction of F. benjamina extracts. Flavonoids were collected from the leaf ethanol extracts through repeated purification procedure and HPLC analysis. The antiviral activity of each substance was then evaluated in cell culture. Three known flavone glycosides, (1) quercetin 3-O-rutinoside, (2) kaempferol 3-O-rutinoside and (3) kaempferol 3-O-robinobioside, showing highest antiviral efficiency were selected and their structure was determined by spectroscopic analyses including NMR and mass spectrometry (MS). These three flavones were highly effective against HSV-1 reaching a selectivity index (SI) of 266, 100 and 666 for compound 1, 2 and 3, respectively, while the SI of their aglycons, quercetin and kaempferol amounted only in 7.1 and 3.2, respectively. Kaempferol 3-O-robinobioside showed similar SI to that of acyclovir (ACV), the standard anti-HSV drug. Although highly effective against HSV-1 and HSV-2, these flavone glycosides did not show any significant activity against VZV.     

Antimicrobial activity against <Emphasis Type="Italic">Streptococcus sobrinus</Emphasis> and glucosyltransferase inhibitory activity of taxifolin and some flavanonol rhamnosides from kempas (<Emphasis Type="Italic">Koompassia malaccensis</Emphasis>) extracts

Twenty plant materials collected from the islands of Java and Kalimantan in Indonesia were extracted with 50% aqueous ethanol (crude extract). The crude extracts were assayed for antimicrobial activities against Streptococcus sobrinus and for glucosyltransferase (GTase) inhibition. Fourteen extracts inhibited the growth of S. sobrinus by more than 50% and six extracts inhibited GTase activity by more than 50% at a concentration of 100 μg/ml. Koompassia malaccensis (kempas) extracts showed 90% depression of S. sobrinus growth and 80% inhibition of GTase activity at a concentration of 100 μg/ml. Kempas crude extracts were subjected to column chromatography using Sephadex LH-20 and then preparative high-performance liquid chromatography to isolate four compounds A, B, C, and D. These compounds were identified as taxifolin and the flavanonol rhamnoside isomers neoastilbin, astilbin, and isoastilbin, respectively, from ¹H and ¹³C nuclear magnetic resonance (NMR) spectra and other two-dimensional NMR techniques (COSY, HMBC, and HMQC). Each compound depressed the growth of S. sobrinus over a concentration range of 9.3242.7 μg/ml and showed GTase inhibitory activity with IC₅₀ values in the range 27.4–57.3 μg/ml. Taxifolin and flavanonol rhamnoside isomers isolated for the first time from kempas could be potent compounds for preventing dental caries. Part of this report was presented at the 57th Annual Meeting of the Japan Wood Research Society Conference, Hiroshima, 2007     

森吉木霉M75发酵粗提液对松球壳孢菌的抑菌机制研究

目的 研究森吉木霉M75发酵粗提液对松球壳孢菌Sphaeropsis sapinea代谢系统及生理生化的影响,探究其抑菌机制。 方法 采用分光光度计法,分别测定在不同处理时间段内森吉木霉M75发酵粗提液对松球壳孢菌代谢系统酶活性,以及对电导率、丙二醛含量的影响。 结果 森吉木霉M75发酵粗提液可显著影响松球壳孢菌代谢系统中各关键酶活性。其中超氧化物歧化酶（SOD）、过氧化氢酶（CAT）、过氧化物酶（POD）、多酚氧化酶（PPO）在处理8~12 h内达到峰值,为75.25 U·（g·min）−1、0.066 U·（g·s）−1、5.8 U·（g·s）−1和12.33 U·（g·s）−1,分别是初始时的1.96、6.09、16.37和7.86倍;丙酮酸激酶（PK）、己糖激酶（HK）和乳酸脱氢酶（LDH）在处理12~24 h内显著下降,由初始时的0.55、0.066、2.35 U·（g·min）−1下降至0.18、0.03、0.66 U·（g·min）−1,后下降趋缓;琥珀酸脱氢酶（SDH）、苹果酸脱氢酶（MDH）和辅酶Ⅰ含量在处理12 h内呈快速下降趋势,由初始时的30.33 U·（g·min）−1、15.55 U·（g·min）−1、5.70 nmol·（g·min）−1分别下降至10.00 U·（g·min）−1、3.65 U·（g·min）−1、1.34 nmol·（g·min）−1,处理12 h后呈缓慢下降趋势,而对照组则不断升高;Na+,K+-ATP、Mg++-ATP和Ca++-ATP酶活性在处理8 h或12 h时达到峰值,分别为0.09、1.76和3.18 μmolPi·（g·h）−1;此后迅速下降,处理24 h后下降趋缓并逐渐趋于0;松球壳孢菌细胞膜电导率在处理12 h内显著升高,且处理组在各时间段的电导率值始终高于对照组;丙二醛含量在处理24 h内显著升高并达到峰值1.06 nmol·g−1,处理24 h至96 h内呈缓慢下降趋势,但在各处理时间段仍显著高于对照组。 结论 森吉木霉M75发酵粗提液通过破坏松球壳孢菌的防御系统,阻碍了病原菌正常的生理代谢路径,从而抑制病原菌的正常生长。