五鹤续断中总生物碱的质量分数分析

采用索氏提取法对不同生长时期的五鹤续断中总生物碱进行提取并分离,探讨用紫外分光光度法测定总生物碱质量分数的方法.结果表明:随着生长年限的增加,其根中总生物碱的质量分数积累呈现出递增趋势.但是茎、叶中总生物碱的质量分数很低.因此,三年生的五鹤续断根为较好的药材,具有较好的药用价值和开发价值.     

双稠哌啶类生物碱对5个环境细菌菌株的抑制作用

测定了槐定碱、槐胺碱、苦参碱、野靛碱、氧化苦参碱和苦豆草总生物碱对大肠杆菌、产气杆菌、变形杆菌、枯草杆菌、白色葡萄球菌 (即表皮葡萄球菌 )的最低抑菌浓度 (MIC)。结果表明 5种生物碱和苦豆草总生物碱对 5个环境细菌菌株的生长均产生了明显的抑制作用。5种生物碱对 5种环境细菌的最低抑菌浓度除了野靛碱对变形杆菌为 5× 1 0 - 3 mol/L ,其它均在 2× 1 0 - 2 ～ 5× 1 0 - 2 mol/L之间。然而苦豆草总生物碱对 5种环境细菌的最低抑菌浓度却明显较 5种生物碱的为低 ,其中对大肠杆菌和枯草杆菌的最低抑菌浓度达到 5× 1 0 - 3 mol/L。结合双稠哌啶类生物碱在植物中的含量和分布 ,讨论了双稠哌啶类生物碱在开发防治农林细菌病害及医药产品方面的应用价值和在植物化学生态学中的防御作用。     

酸性染料比色法测定千里光总生物碱含量

目的:研究测定千里光中总生物碱含量的方法。方法:以氧化苦参碱为对照品,采用酸性染料比色法,在422 nm波长处测定千里光中总生物碱含量。结果:氧化苦参碱在6.75~135μg与吸光度呈良好的线性关系(r=0.999 2),平均回收率100.0%(RSD=1.54%)。结论:该方法简便、准确,可用于千里光中总生物碱的测定。     

苦豆子生物碱抗菌活性的测定

采用抑菌圈法测定了槐定碱、苦参碱、氧化苦参碱、氧化槐果碱、苦豆子总碱对大肠杆菌、金黄色葡萄球菌、枯草芽孢杆菌、番茄早疫、番茄灰霉和辣椒炭疽的抗菌活性。试验结果表明,5种生物碱对3种细菌生长均具有显著的抑制作用,其中槐定碱和苦参碱对大肠杆菌、枯草芽孢杆菌和番茄早疫的抗菌效果明显优于其他3种生物碱,苦参碱对大肠杆菌和枯草芽孢杆菌的最小抑菌浓度（MIC）达到12.5μg/mL。5种生物碱对3种真菌的抗菌效果弱于对3种细菌的抗菌效果,5种生物碱对3种真菌的MIC大于等于100μg/mL,氧化苦参碱、氧化槐果碱和苦豆子总碱对番茄灰霉菌的MIC均达400μg/mL。在质量浓度为100μg/mL时,5种生物碱中仅槐定碱表现出对辣椒炭疽菌的抑制作用。苦豆子总碱抗菌活性影响因素的试验结果表明,苦豆子总碱具有良好的热稳定性,在弱碱性条件下(pH 8左右)具有更好的抑菌活性,在至少12h内能够持续、稳定的对供试菌产生抑制作用。     

Chemical basis of pupal cannibalism in a caterpillar (Utetheisa ornatrix)

The mothUtetheisa ornatrix derives protection against predation from systemic pyrrolizidine alkaloids (PAs) that it sequesters as a larva from its foodplants (Leguminosae,Crotalaria spp.). We here show, in laboratory tests, thatUtetheisa deficient in body PA can make up for the chemical shortfall by cannibalizing pupae. We present evidence indicating that cannibalism in larvae is elicited not by hunger, but possibly by PA deficiency itself, and that in making cannibalistic choices larvae prefer PA-containing over PA-free pupae. PAs themselves, either in crystalline form or as additives to food items, proved phagostimulatory to larvae. In natureUtetheisa tend to pupate away from their foodplant, essentially out of reach of larval attack. The threat of cannibalism may have contributed to the evolution of this pupation behavior.Paper No. 102 of the series Defense Mechanisms of Arthropods; No. 101 is Eisner et al., Chemoecology (in press).     

Biogenesis ofElaeocarpus andPeripentadenia alkaloids

Summary A pathway for the biogenesis of alkaloids ofElaeocarpus andPeripentadenia spp. (Elaeocarpaceae) is put forward, which involves methionine as the source of the central C3 unit in the structures of all these bases except mearsine, for which acetate units appear to furnish all the carbon atoms in its structure.     

Pyrrolizidine alkaloids in overwintering monarch butterflies (Danaus plexippus) from mexico

Summary North American populations of the monarch butterfly,Danaus plexippus, have been found to contain pyrrolizidine alkaloids and their N-oxides. Analytical methods (TLC, GC, and GC/MS) have been developed to isolate, quantitate, and structurally elucidate the alkaloids. Examples of at least two classes of pyrrolizidine alkaloids have been identified, the macrocyclic diesters, senecionine, integerrimine, and seneciphylline, and the monoesters, echinatine, intermedine, and lycopsamine.21 November 1986This work was supported by NSF (Grants BSR-81-19391 and BSR-81-19382), and a Stauffer Chemical Company fellowship. We thank David Hodapp, Mark Stelljes, and Cordula Bruenner for technical help, Dr T.P. Krick, University of Minnesota, St. Paul, Minn., USA, for assistance in GC/MS analysis of PAs, and Dr J.A. Edgar, CSIRO, Parkville, Victoria, Australia, for samples of authentic reference compounds.     

苦参提取物质量标准研究

为研究并建立苦参提取物的质量标准,按照《药典》相关技术要求分别建立苦参提取物性状、薄层色谱鉴别、水分、灰分、炽灼残渣、重金属及砷盐等项目的检查方法并规定限度,采用滴定法建立苦参提取物的总生物碱含量测定方法并规定了限度.结果显示：苦参提取物的水分不应超过5.0%,重金属不应超过10ppm,总生物碱含量应在35.00%~52.50%之间.本研究建立的质量标准可以控制苦参提取物的质量.     

剑叶木姜子的化学成分研究

 对剑叶木姜子(Litsea lancifolia)的化学成分进行研究.采用硅胶柱层析、重结晶等分离手段从中分离纯化得到8个化合物,通过现代波谱技术和理化常数测定鉴定了它们的结构,其中3个为异喹啉生物碱:lit-seglutine A(1),phanostenine(2),juziphin(3);同时还得到(E)-6-hydroxy-4,6-dimethyl-3-heptene-2-one(4),香草醛(vanillin,5),香草酸(vanillic acid,6),β-谷甾醇(7)及β-胡萝卜苷(8).以上化合物均为首次从该植物中分离得到.     

文殊兰弱碱性生物碱的抗肿瘤活性研究

研究文殊兰中弱碱性生物碱对不同肿瘤细胞的抑制作用,并筛选出敏感细胞株,观察凋亡形态;MCF-7细胞株、SMMC7721细胞株、SGC7901细胞株、HepG-2细胞株,MTT溶液,DMSO,Hoechst33258等;利用MTT法检测文殊兰弱碱性生物碱对上述肿瘤细胞的抑制作用以及Hoechst 33258染色法观察细胞凋亡的形态学变化;文殊兰弱碱性生物碱对上述细胞株均有明显的抑制作用,对HepG-2细胞的抑制作用更为明显,给药72 h后测定IC50=9.374 323μg/mL;Hoechst 33258染色法观察细胞出现凋亡小体,有凋亡现象发生.文殊兰弱碱性生物碱MCF-7细胞株、SMMC7721细胞株、SGC7901细胞株、HepG-2细胞株具有不同程度的抑制作用,且呈现一定的剂量依赖性,对HepG-2细胞的抑制作用最强,表现出良好的抗肿瘤活性.