Antiplasmodial activity of extracts from seven medicinal plants used in malaria treatment in Cameroon

Aim of the study

In a search for new plant-derived biologically active compounds against malaria parasites, we have carried out an ethnopharmacological study to evaluate the susceptibility of cultured Plasmodium falciparum to extracts and fractions from seven Cameroonian medicinal plants used in malaria treatment. We have also explored the inhibition of the Plasmodium falciparum cysteine protease Falcipain-2.

Materials and methods

Plant materials were extracted by maceration in organic solvents, and subsequently partitioned or fractionated to afford test fractions. The susceptibility of erythrocytes and the W2 strain of Plasmodium falciparum to plant extracts was evaluated in culture. In addition, the ability of annonaceous extracts to inhibit recombinant cysteine protease Falcipain-2 was also assessed.

Results and discussion

The extracts showed no toxicity against erythrocytes. The majority of plant extracts were highly active against Plasmodium falciparumin vitro, with IC₅₀ values lower than 5 μg/ml. Annonaceous extracts (acetogenin-rich fractions and interface precipitates) exhibited the highest potency. Some of these extracts exhibited modest inhibition of Falcipain-2.

Conclusion

These results support continued investigation of components of traditional medicines as potential new antimalarial agents.     

New prenylated flavones from <Emphasis Type="Italic">Artocarpus champeden</Emphasis>, and their antimalarial activity in vitro

Two new prenylated flavones, artocarpones A and B (1 and 2), and seven known isoprenylated flavonoids, artonin A (3), cycloheterophyllin (4), artoindonesianin E (5), artoindonesianin R (6), heterophyllin (7), heteroflavanone C (8), and artoindonesianin A-2 (9), have been isolated from the stem bark of Artocarpus champeden. Their structures were determined by spectroscopic analysis. Among the compounds isolated, 8 had the most potent inhibitory activity against the growth of Plasmodium falciparum 3D7 clone, with an IC₅₀ value of 1 nmol L⁻¹.     

An oxepinoflavone from <Emphasis Type="Italic">Artocarpus elasticus</Emphasis> with cytotoxic activity against P-388 cells

A new oxepinoflavone, artoindonesianin E1 (1), was isolated from the wood of Artocarpus elasticus, along with four known prenylated flavones: artocarpin (2), cycloartocarpin (3), cudraflavones A (4) and C (5). The structure of the new compound was identified by spectroscopic methods. Upon cytotoxic evaluation against murine leukemia P-388 cells, the new compound showed IC₅₀ 5.0 μg/mL.     

Comparison of antigenic and allergenic components of Holoptelea integrifolia pollen collected from different source materials

Antigenic extracts prepared from pollen samples collected at weekly intervals during the same season did not exhibit significant variation in protein concentration. Stored pollen samples from different years, however, showed highly significant variations in protein concentration. The protein content of samples from different ecozones of India also varied (CV = +/- 32%). The IEF and SDS-PAGE patterns were almost identical in samples from the same season, but were variable in the samples stored from different years and different parts of India. IgE binding proteins from different samples also varied depending on the overall protein profiles. Almost all the patients, however, showed IgE binding to four proteins at 50, 60, 66 and 70 kD, indicating the important allergenic components of Holoptelea integrifolia.     

白桂木抗类风湿性关节炎的有效部位筛选及其作用机制研究

目的 筛选白桂木抗类风湿性关节炎的有效部位,初步探讨白桂木有效部位抗类风湿性关节炎的作用机制。方法 制备白桂木根总提取物、石油醚提取部位、醋酸乙酯提取部位、氯仿提取部位,观察连续15 d ig给予大鼠白桂木根各提取物对大鼠佐剂性关节炎的影响。结果 白桂木醋酸乙酯提取部位显著改善大鼠佐剂性关节炎的症状,抑制大鼠血清中致炎物质前列腺素E₂（PGE₂）和一氧化氮（NO）的生成。结论 白桂木醋酸乙酯提取部位可能是其治疗类风湿性关节炎的有效部位,其抗类风湿关节炎作用与抑制血清中PGE₂和NO等致炎物质的生成有关。     

西藏产全缘叶绿绒蒿的化学成分研究

目的:对藏药材全缘叶绿绒蒿(Meconopsis integrifolia Franch.)的化学成分进行分离纯化和结构鉴定。方法:采用正反相硅胶柱色谱和Sephadex LH-20凝胶柱色谱方法进行分离纯化,NMR和MS等波谱方法进行结构鉴定。结果:从青海产藏药全缘叶绿绒蒿地上部分甲醇提取物中分离得到8个化合物:去甲血根碱(norsanguinarine)①,β-谷甾醇(β-sitosterol)②;3-羟基-奇墩果烷-12(13)-烯-30-酸(3-hydroxyolean-12(13)-en-24-oic acid)③;6-丙酮基-5,6-二氢血根碱(6-acetonyl-5,6-dihydrosanguinarine)④;木犀草素(1uteolin)⑤;胡萝卜苷(daucosterol)⑥;quercetin 3-O-β-D-glucopyranosyl-(1→0)-β-D-glucopyranoside⑦;普托品(protopine)⑧。结果:化合物1,4和7为首次从该种植物中分离得到。     

澳洲坚果果仁营养成分分析

<正>澳洲坚果(Macadamia integrifolia),属山龙眼科(Proteaceae),澳洲坚果属(Macadamia)常绿乔木果树,又称夏威夷果、澳洲核桃、昆士兰坚果。原产于澳大利亚昆士兰州东南部和新南     

牛李化学成分分离鉴定

目的:研究波罗蜜属植物牛李Artocarpus nigrifolius枝条的化学成分。方法:采用硅胶,小孔树脂(MCI gel),LH-20羟丙基葡聚糖凝胶(Sephadex LH-20),ODS,HPLC等柱色谱分离手段,对牛李干燥枝条的95%乙醇提取物进行了系统的化学成分研究,根据化合物的理化性质及光谱数据鉴定其结构。结果:共分离了26个化合物,大部分为三萜类成分。包括16个三萜,2个降三萜,6个甾醇,1个苯甲醛衍生物和1个小分子胺类化合物。分别鉴定为20-hydroxy-4α,4β,14α-trimethyl-9β,19-cyclopregnane-3-one(1),1-(N-叔丁基)氨基丙酮(2),24-methylenecycloartanone(3),cyclolaudenone(4),24-methylenecycloartanol(5),4-羟基-3,5-二甲氧基苯甲醛(6),环桉烯醇(7),cycloart-23-ene-3β,25-diol(8),β-谷甾醇(9),3β,24,25-trihydroxycycloartane(10),(23E)-27-nor-3α-hydroxycycloart-23-en-25-one(11),3β-hydroxy-22,23,24,25,26,27-hexanordammarane-20-one(12),12-en-3β-hydroxy-olean-11-one(13),(24S)-cycloartane-24,25-diol-3-one(14),桦木酸(15),羽扇豆醇(16),α-香树脂醇(17),(22E)-25,26,27-trinor-3β-hydroxycycloart-22-en-24-al(18),3β-hydroxy-urs-11-en-13β,28-olide(19),11α-hydroxy-α-amyrin(20),3β-羟基豆甾-5,22-二烯-7-酮(21),7-ketositosterol(22),β-香树脂醇(23),(24S)-麦角甾-5-烯-3β,7α,二醇(24),7α-hydroxysitosterol(25)和7β-hydroxysitosterol(26)。结论:化合物1为新的环阿屯烷型C_(24)降三萜,化合物2为首次以天然产物的形式从自然界中获得,化合物6,8,11,15~17,20,22和23均为首次从波罗蜜属植物中分离得到,其余化合物均为首次从桑科植物中分离得到。三萜类成分可能为牛李的抗肿瘤活性物质基础,值得进一步深入研究。     

波罗蜜根酚性化学成分研究

目的研究桑科植物波罗蜜Artocarpus heterophyllus根酚性化学成分。方法运用ODS、MCI CHP-20P、Sephadex LH-20等柱色谱和高效液相色谱技术从波罗蜜根中分离化合物,并根据理化性质和NMR、MS波谱数据鉴定化合物结构。结果从波罗蜜根95%乙醇提取物中分离得到17个酚性化合物,分别鉴定为1-O-阿魏酰甘油(1)、hypargystilbene A(2)、氧化白藜芦醇(3)、2′,3,4′,5,5′-五羟基-顺式-均二苯代乙烯(4)、白藜芦醇(5)、2,4-二羟基苯甲酸乙酯(6)、原儿茶酸乙酯(7)、伞形花内酯(8)、8-(3,3-二甲基烯丙基)-6,7-二羟基香豆素(9)、桑查耳酮A(10)、桂木二氢黄素(11)、styracifolin C(12)、柘树黄酮C(13)、异叶波罗蜜素(14)、环异叶波罗蜜素(15)、artonin A(16)和artonin B(17)。结论化合物9为首次从天然产物中分离得到,化合物1、4和6为首次从桑科植物中分离得到,化合物8为首次从波罗蜜属植物中分离得到,化合物3、5、10、11、14和15为首次从波罗蜜中分离得到。     

二色桂木正丁醇提取物的抗抑郁活性研究

目的:探讨二色桂木提取物的抗抑郁活性及其作用机制。方法:采用KM种小鼠(雄性)悬尾、强迫游泳和利血平诱导抑郁症模型,以ig连续给药10 d(空白组等容生理盐水;氟西汀组50 mg·kg-1;二色桂木粗提物及其石油醚、乙酸乙酯、正丁醇部位及水部位各给药组200 mg·kg-1),研究二色桂木醇提物及其不同极性部位的抗抑郁活性;采用荧光分光光度法测定海马及纹状体5-羟色胺(5-HT)。结果:二色桂木醇提物及石油醚部位、乙酸乙酯部位、正丁醇部位和水部位均可不同程度地缩短小鼠游泳和悬尾的不动时间,其中正丁醇部位的作用最显著(P<0.05或P<0.01),并能显著拮抗利血平引起的体温下降和眼睑下垂等生理变化(P<0.05或P<0.01),显著提高5-HT在海马、纹状体中的含量(P<0.05或P<0.01)。结论:二色桂木醇提物具有抗抑郁作用,其活性成分主要分布在正丁醇部位。