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11.
12.
目的研究苦豆子总生物碱对小鼠乳腺癌4T1细胞体外增殖抑制及诱导凋亡作用。方法苦豆子总生物碱提取并纯化,处理成澄清的药物溶液后用于细胞给药。CCK-8法测定不同浓度的苦豆子总生物碱作用24h后4T1细胞存活率。流式细胞术检测给药24h后4T1细胞凋亡率。结果与对照组比较,实验组药物浓度为5.00mg/mL时,4T1细胞存活率为63.05%;药物浓度为10.00mg/mL时,4T1细胞存活率为20.30%,随着给药浓度的增加,细胞存活率呈明显下降趋势。实验组药物浓度为6.25mg/mL时,细胞凋亡率为11.4%;药物浓度为10.00mg/mL时,细胞凋亡率为41.7%,随着给药浓度的增加,细胞凋亡率明显增加。结论苦豆子总生物碱能诱导细胞凋亡,对小鼠乳腺癌4T1细胞的增殖有明显抑制作用。 相似文献
13.
《药学学报(英文版)》2017,7(3):334-341
Six new indole alkaloid sulfonic acids (1–6), together with two analogues (7 and 8) that were previously reported as synthetic products, were isolated from an aqueous extract of the Isatis indigotica root. Their structures including the absolute configurations were determined by spectroscopic data analysis, combined with enzyme hydrolysis and comparison of experimental circular dichroism and calculated electronic circular dichroism spectra. In the preliminary assay, compounds 2 and 4 showed antiviral activity against Coxsackie virus B3 and influenza virus A/Hanfang/359/95 (H3N2), respectively. 相似文献
14.
Laura M. Jones Kristin E. Ceniccola-Campos David R. Morello 《Drug testing and analysis》2022,14(3):519-524
Drug Enforcement Administration's (DEA) Cocaine Signature Program previously identified 19 coca-growing regions within South America and developed methodology to geo-source cocaine using a combination of trace cocaine alkaloids, stable isotopes, and multivariate statistics. Twenty-nine coca leaf samples collected in 2016 and 2019 from a previously unanalyzed coca-growing region located in Puno, Peru, were analyzed with this methodology. Trace cocaine alkaloids and stable isotopes were compared with other Peruvian regions. Minor differences were observed in the extracted cocaine alkaloid profiles when compared with samples collected from the Ucayali-Huallaga Valley and Cusco-Apurimac regions while the stable isotopes of δ2H (−177.1‰) and δ18O (23.8‰) were enriched. Puno's alkaloid and stable isotope results are presented in this publication to assist forensic laboratories and enhance their cocaine geo-sourcing capabilities. 相似文献
15.
Abhisheak Sharma Shyam H. Kamble Francisco Len Nelson J.‐Y. Chear Tamara I. King Erin C. Berthold Surash Ramanathan Christopher R. McCurdy Bonnie A. Avery 《Drug testing and analysis》2019,11(8):1162-1171
Kratom (Mitragyna speciosa) is a psychoactive plant popular in the United States for the self‐treatment of pain and opioid addiction. For standardization and quality control of raw and commercial kratom products, an ultra‐performance liquid chromatography?tandem mass spectrometry (UPLC?MS/MS) method was developed and validated for the quantification of ten key alkaloids, namely: corynantheidine, corynoxine, corynoxine B, 7‐hydroxymitragynine, isocorynantheidine, mitragynine, mitraphylline, paynantheine, speciociliatine, and speciogynine. Chromatographic separation of diastereomers, or alkaloids sharing same ion transitions, was achieved on an Acquity BEH C18 column with a gradient elution using a mobile phase containing acetonitrile and aqueous ammonium acetate buffer (10mM, pH 3.5). The developed method was linear over a concentration range of 1–200 ng/mL for each alkaloid. The total analysis time per sample was 22.5 minutes. The analytical method was validated for accuracy, precision, robustness, and stability. After successful validation, the method was applied for the quantification of kratom alkaloids in alkaloid‐rich fractions, ethanolic extracts, lyophilized teas, and commercial products. Mitragynine (0.7%–38.7% w/w), paynantheine (0.3%–12.8% w/w), speciociliatine (0.4%–12.3% w/w), and speciogynine (0.1%–5.3% w/w) were the major alkaloids in the analyzed kratom products/extracts. Minor kratom alkaloids (corynantheidine, corynoxine, corynoxine B, 7‐hydroxymitragynine, isocorynantheidine) were also quantified (0.01%–2.8% w/w) in the analyzed products; however mitraphylline was below the lower limit of quantification in all analyses. 相似文献
16.
Jin-Qian Yu Xiao-Wei Sun Zhi-Wei Wang Lei Fang 《Journal of Asian natural products research》2019,21(8):820-825
One new quinolinic scandine-type monoterpeniod alkaloid, 3-oxo-scandine (1), as well as seven known ones (2–8), was isolated from the roots of Melodinus henryi. Their structures were elucidated by extensive spectroscopic analysis. All of the compounds were prepared and evaluated for their anti-inflammatory activities by measuring the inhibitory activity of nitric oxide (NO) in vitro in RAW 264.7 mouse peritoneal macrophages. Compounds 6 and 7 showed significant activities with IC50 values of 8.54 and 5.19 μM, respectively. 相似文献
17.
Lamellarins 是一类从海洋无脊椎动物中分离的具有生物活性的吡咯生物碱, Neolamellarins,Lukianols, Storniamides, Ningalins 等结构新颖的生物碱都属于该家族。Lamellarins 吡咯类生物碱合成的关键是1,3,4-三取代吡咯环的构建,主要策略有分步构建与一锅法构建吡咯环两类,从中涌现了多种极富创新性与可行性的合成方法,既从结构多样性合成的角度丰富了化合物库,同时又以生物活性为导向提高了该类化合物的生物活性。本文对其结构特点、合成、生物活性进行了综述。 相似文献
18.
左金丸总生物碱缓释片的制备及体外释放度研究 总被引:1,自引:0,他引:1
目的:制备左金丸总生物碱缓释片并考察其体外释放行为。方法:以左金丸总生物碱为主药,以羟丙基甲基纤维素为凝胶骨架材料制备缓释片,并对处方中辅料用量进行正交优化。通过药物释放动力学模型拟合左金丸总生物碱缓释片中盐酸小檗碱和吴茱萸碱的释放过程,并推测其释药机制。结果:每片缓释片中羟丙基甲基纤维素、微晶纤维素和乳糖的最佳用量分别为100、50和15mg。盐酸小檗碱的释放接近Higuchi方程,吴茱萸碱的释放接近Peppas方程,2种成分的释放机制均为药物扩散和骨架溶蚀共同作用。结论:左金丸总生物碱缓释片缓释效果明显,符合设计要求,制备工艺简单可行。 相似文献
19.
目的:在前期药效实验的基础上,提取麦芽总生物碱,优选麦芽总生物碱颗粒剂成型制备工艺,得到稳定均一,质量合格的颗粒制剂。方法:利用超声提取法,提取麦芽总生物碱;采用酸性染料比色法测定麦芽中总生物碱的含量;拟选6个处方完成颗粒剂的制备,并以休止角、成型率、堆密度和吸湿性等为指标,应用综合评分法对各处方进行打分,筛选出最优的辅料处方,完成辅料用量比例的优化,并筛选出最佳润湿剂;对制备所得到的麦芽总生物碱颗粒的溶化性,粒度及干燥失重等进行测定。结果:以糊精和乳糖比例为1:1的混合物作为辅料,并按1:1的比例混合麦芽总生物碱浸膏粉与辅料,选取80%的乙醇作为润湿剂,制备所得颗粒剂大小均一,成型率最高。结论:本文成功优选出了麦芽总生物碱颗粒剂的制备工艺,制成的颗粒溶化性好,成型率佳,制备方法稳定可靠。 相似文献
20.
Lihong Zhao Zhihui Sun Limin Yang Ranji Cui Wei Yang Bingjin Li 《Clinical and experimental pharmacology & physiology》2020,47(4):531-542
Aconiti Lateralis Radix Praeparata (Fuzi in Chinese), which are the lateral roots of Aconitum Carmichaelii Debx, is widely used in China to treat many neurological diseases. Fuzi, in its various forms, has many neuropharmacological effects. It can act as an analgesic and help with depression, epilepsy, and dementia. However, the neuropharmacological effects of Aconiti Lateralis Radix Praeparata are seldom comprehensively reviewed. In this review, the neuropharmacological activities of some components contained in Aconiti Lateralis Radix Praeparata are considered. These include aconitine, mesaconitine, hypaconitine, total alkaloid, polysaccharide-1, benzoylmesaconine, fuziline, songorine, and napelline. We also specifically discuss the antidepressant effects of total alkaloids and polysaccharide-1. This review may provide a theoretical basis for further utilization of Aconiti Lateralis Radix Praeparata for diseases that affect the central nervous system. 相似文献