核桃楸叶乙醇提取物的抑茵活性及活性成分分析

采用常规提取法浸提核桃楸叶的抑菌活性成分。研究结果表明，核桃楸叶乙醇提取物及其乙酸乙酯萃取相对杨树叶枯病菌和樟子松枯梢病菌有抑菌活性，核桃楸叶乙醇提取物及其乙酸乙酯萃取相对杨树叶枯病菌的最低抑菌质量浓度（MIC）为3．12g／L，对樟子松枯梢病菌的MIC为6．25g／L。采用GC-MS分析了核桃楸叶乙醇提取物中乙酸乙酯萃取相经柱层析后集分I和集分Ⅱ的化学组成和相对含量。分析结果表明，乙酸乙酯萃取相中主要活性成分为相对含量较高的5-羟基-1，4-萘醌（胡桃醌）、D-阿洛糖、5，8-二羟基-1，4-萘醌、1，5-萘二酚、2，3-二氢苯并呋喃、7-甲氧基-1-四氢萘酮、1-萘酚、8-羟基-2-甲氧基-1，4-萘醌和4-甲基-2，6-二羟基喹啉等。     

核桃楸外果皮提取物的化感作用及成分分析

采用常规提取法浸提核桃楸外果皮的化感作用成分。研究结果表明,核桃楸外果皮乙醇提取物和乙酸乙酯萃取相对3种受体植物青菜、萝卜和紫花苜蓿具有化感作用(抑制萌发和抑制生长作用)。化感作用随提取物浓度增大而增大。采用GC-MS分析核桃楸外果皮乙醇提取物中乙酸乙酯萃取相的化学组成和相对含量。分析结果表明,核桃楸外果皮乙醇提取物中乙酸乙酯萃取相的主要化学成分为5-羟基-1,4-萘醌(胡桃醌),GC含量31.20%;正十六酸,GC含量9.99%;7-甲氧基-1-四氢萘酮,GC含量7.99%;1,5-萘二酚,GC含量7.15%;2,6-二甲氧基苯酚,GC含量4.36%;4-丁氧基苯醛;GC含量3.23%;5-羟甲基-2-呋喃醛,GC含量2.96%;二聚1,3-二羟基丙酮,GC含量2.94%;丙三醇,GC含量2.77%;1(3H)-异苯并呋喃酮,GC含量2.57%。     

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.     

核桃楸叶乙醇提取物对舞毒蛾幼虫的毒杀效果

采用常规提取法浸提核桃楸叶的杀虫活性成分,其中乙醇提取物对舞毒蛾有显著的触杀和胃毒作用,且两种作用方式无显著差异,施药时间≥3 d、药液浓度≥5g/L时,平均校正死亡率均超过50%.核桃楸叶乙醇提取物的触杀和胃毒作用强于氯仿萃取相和乙酸乙酯萃取相.     

几种桉叶提取物的抗菌活性研究

研究了大叶桉、柠檬桉、尤曼桉(A、B)叶乙醇提取物和大叶桉、尤曼桉B叶提取物浓缩浸膏的石油醚、乙酸乙酯和正丁醇萃取组分对金黄葡萄球菌、大肠杆菌、枯草芽孢杆菌、黄瓜枯萎病菌的抗菌活性和以及这几种桉叶提取物的最低抑菌浓度。结果表明4种桉叶提取物对4种供试菌均有抑制作用,对金黄葡萄球菌、枯草芽孢杆菌抑制作用强,对黄瓜枯萎病菌作用弱。大叶桉、尤曼桉B提取物的抗菌活性强,这两种桉叶的乙酸乙酯和正丁醇萃取组分对4种供试菌抑菌作用最明显。     

滇白珠种子抗炎化学成分的研究

采用小鼠耳肿胀法对滇白珠种子75%乙醇提取物的石油醚、氯仿、乙酸乙酯、正丁醇萃取物和水溶部分的抗炎效果进行测试。结果表明乙酸乙酯萃取物能显著减轻二甲苯致炎小鼠的耳廓肿胀度。采用色谱技术分离抗炎效果较好的乙酸乙酯萃取物的化学成分,得到8个化合物。通过NMR、IR、MS等波谱法鉴定,8个化合物为:大黄素甲醚(1)、6-乙基-5-羟基-2,7-二甲氧基-1,4-萘醌(2)、杨梅素(3)、对苯二酚(4)、香草酸(5)、β-胡萝卜苷(6)、β-谷甾醇(7)和丁二酸(8)。以上所有化合物都为首次从滇白珠种子中分离得到。     

湘西虎杖抑菌成分提取及其抑菌活性研究初报

以乙醇作溶剂,对湘西虎杖抑菌活性物提取条件进行研究,通过抑菌实验得到最佳提取条件为A3B2C3,即90%乙醇、60℃、3h, 该条件下的提取物对细菌生长的抑制活性最强,但对酵母菌无明显的效果,对三种受试细菌的最小抑菌浓度(MIC)为0.25~ 0.5g/ml。提取物经85℃、100℃,15 min 或pH2~8 处理后仍具有较强的抑菌活性,其乙酸乙酯萃取物对三个菌都有较强的抑菌活性。     

减压蒸馏法提取核桃楸树皮中的胡桃醌

胡桃醌(5-羟基-1,4-萘醌)是从核桃楸中提取分离出来的一种萘醌类活性物质.研究采用超声波辅助浸提和减压蒸馏等方法,从核桃楸树皮中提取制得胡桃醌产品,产品得率 0.09%.分别用FT-IR表征了产品的有机官能团、用GC-MS分析了产品的化学组成和产品中胡桃醌的相对含量(GC含量达 96.42%)、通过 1 H NMR确认了产品的胡桃醌结构.本研究提供了一种从核桃楸树皮中简便快捷地提取制得高纯度的胡桃醌产品的方法.     

苍耳对苹果轮纹病菌等的抑菌活性研究

以苍耳根、茎、叶作为试验材料,以丙酮、80%乙醇、乙酸乙酯、蒸馏水作为提取溶剂,利用滤纸片法研究了苍耳不同器官4种不同溶剂提取液对2种细菌和1种真菌的抑菌活性,结果表明:苍耳各器官的不同溶剂提取液抑菌效果不同。对溶剂来说,苍耳叶丙酮、乙酸乙酯提取液对枯草芽孢杆菌的抑菌圈直径分别达16.32mm、15.66mm,叶的乙酸乙酯提取液对苹果轮纹病菌的抑菌圈直径达15.64mm,4种不同溶剂提取液的总体抑菌活性由大到小依次为丙酮、乙酸乙酯、80%乙醇、蒸馏水;对不同器官来说,苍耳各器官提取液抑菌效果由大到小依次为叶、根、茎,尤以叶的丙酮提取液抑菌效果最佳,乙酸乙酯次之。苍耳叶的丙酮、乙酸乙酯提取液对枯草芽孢杆菌、苹果轮纹病菌均表现为较强的抑菌活性,但对大肠杆菌的抑菌活性较弱。     

核桃叶中抗植物病毒活性物质提取条件的研究

以不同溶剂和方法对核桃叶进行了抗植物病毒物质的提取和活性测定.结果表明:提取物的抗病毒活性因提取溶剂和提取方法的不同而异.以体积分数 95 % 乙醇为提取溶剂,冷浸提取物在质量浓度 10 g/L 时,对烟草花叶病毒(TMV) 的抑制率最高,为 100 %.采用冷浸提取时,核桃叶中抗TMV活性物质提取的优化条件是:以体积分数 95 % 乙醇为提取溶剂,料液比1:10(g:mL),提取 18 h,得率 21.42 %.质量浓度 5 g/L 的提取物对TMV侵染心叶烟的抑制率为 100 %.该提取物的乙酸乙酯萃取物经多次层析分离和纯化得到黄酮类化合物A,质量浓度 0.5 g/L 的化合物A对TMV侵染心叶烟的抑制率达 85.55 %,说明化合物A是乙酸乙酯萃取物中的主要抗病毒活性成分之一.     

Insecticidal activities and active components of the alcohol extract from green peel of Juglans mandshurica

The extract of green peel of Juglans mandshurica Maxim was extracted by common method for studying its insecticidal activities and analyzing the active components. Results showed that the alcohol extract and the chloroform part of extract （separated with chloroform from alcohol extract） form green peel of J. mandshurica have insecticidal activities in contact toxicity and stomach toxicity against larvae of Lymantria dispar L.. After application of the extracts for five days, the corrected mortality of larvae of Lymantria dispar for both extracts was more than 50% in contact toxicity and stomach toxicity at the concentration of ≥ 5 g·L^-1. The insecticidal activity for both alcohol extract and chloroform part of extract is more effect in contact toxicity than in stomach toxicity, but no significant difference in the insecticidal activities was found between alcohol extract and chloroform part of extract. The active components in the chloroform part of extract from green peel of.J. mandshurica were analyzed by GC-MS. The analyzed results showed that the active components in the chloroform part of extract are： （1） joglone （5-hydroxy-1,4- naphthaoquinone）, the relative content 27.11%, （2） 1,5-Naphthalenediol, the relative content 9.52%, （3） 7-Methoxy-1-tetralone, the relative content 6.81%, （4） Benzofuran, 2,3-dihydro-, the relative content 6.76%, （5） 4-Hydroxy-2-methoxycinnamaldehyde, the relative content 3.99%, （6） 2-Methoxy-4-vinylphenol, the relative content 3.05%.     

柿叶化学成分及其抑菌活性研究

对柿叶的化学成分进行了定性分析和抗菌活性的研究.通过系统预试,初步确定柿叶中含有生物碱、皂苷、氨基酸、多肽、有机酸、酚类和鞣质、糖类、甾体、总黄酮、强心苷、蒽醌、挥发油等物质.抑制活性试验结果显示:乙醇提取物和乙酸乙酯萃取物对供试的6种细菌有较强的抑制作用;水相对供试的5种真菌有较强的抑制作用,而且对细菌有较小抑制作用;石油醚相对真菌和细菌几乎无抑制作用;正丁醇萃取物对细菌有不同程度的抑制作用,而对真菌无抑制作用.用不同质量浓度的乙酸乙酯提取物进行抑菌活性试验,结果显示:质量浓度越高,其抑菌能力越强,而且,在不同质量浓度下,对测试的6个细菌的抑制活性的大小顺序不一致.     

Antimicrobial activity of Eupatorium ayapana

Petroleum ether and methanolic extracts of leaves of Eupatorium ayapana were tested for their antimicrobial activity. The petroleum ether extract showed higher antibacterial and antifungal activity than the methanolic extract.     

Fate and influence of western red cedar extractives in mechanical pulping

The methanol extractives from western red cedar mechanical pulps were found to be radically different in composition to the extractives obtained from the heartwood. The major heartwood extractive components, the tropolones and lignans, were not present in the extractives from the pulps. However, the proportion of a brown polymer doubled. The low and high molecular weight methanol extractives components from the pulps were separated using methyl tert-butyl ether. The low molecular fraction contained mostly guaiacyl-based compounds with dihydroquercetin, thujic acid, 3-hydroxy-1-(4′-hydroxy-3′-methoxyphenyl)-2-oxopropane and 4-ethyl-2-methoxy-6-hydroxyphenol being positively identified. The brown polymeric portion had molecular weights ranging from 1,000 to 10,000. Infrared analysis indicated that the polymers were formed from lignans. Examination of the changes in diffuse reflectance UV-visible and infra red spectra of the pulps on extraction with methanol, suggested that the colour resides in insoluble polymers formed from plicatic acid/plicatin during refining. Received 18 December 1998     

Antimicrobial activity and cytotoxicity of Zanthoxylum budrunga

The petroleum ether, chloroform and methanol extracts of the leaves and barks of Zanthoxylum budrunga have been evaluated for their antibacterial, antifungal and cytotoxic properties.     

Phytochemical and antimicrobial study of Chukrasia tabularis leaves

Successive petroleum ether, benzene, chloroform, ethyl acetate and methanol extracts of Chukrasia tabularis leaves were tested for their phytochemical constituents, antibacterial and antifungal activity. The ethyl acetate and methanol extracts were found to be most effective against most of the tested organisms.     

大戟狼毒不同部位提取物对朱砂叶螨的触杀活性

研究大戟狼毒不同部位不同溶剂提取物对朱砂叶螨的生物活性。结果表明:大戟狼毒根石油醚提取物杀螨活性高于根的其他溶剂和茎、叶不同溶剂提取物。该提取物对朱砂叶螨雌成螨有较高的触杀活性,质量浓度为1mg·mL-1时,24h后雌成螨的校正死亡率达到52.73%,对卵的效果相对较差,质量浓度为4mg·mL-1时卵的校正死亡率为55.21%。进一步对大戟狼毒根石油醚提取物进行萃取分离及生物活性跟踪测定发现:萃取物中石油醚相的活性明显大于氯仿相和甲醇相;对石油醚萃取物的柱层析分离最终得到16个流分,其中以第11个流分杀螨效果最好,质量浓度为1mg·mL-1时,24h后雌成螨的校正死亡率达到86.67%,质量浓度为4mg·mL-1时卵的校正死亡率为66.33%。     

Antimicrobial properties of Indigofera dendroides leaves

The antibacterial and antifungal activities of the aqueous, petroleum ether, methanol extracts and eight TLC fractions of the methanol extract of Indigofera dendroides leaves have been evaluated.