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.     

白藓粗取物体外抗菌作用初步研究

研究白藓茎叶及种壳醇提物的的体外抗菌活性。以大肠杆菌、普通变形杆菌、枯草芽孢杆菌、金黄色葡萄球菌4中常见菌为试验菌株,采用药敏纸片扩散法、试管二倍稀释法,对白藓茎叶及种壳醇提物进行抑菌试验。结果表明,白藓茎叶及种壳醇提物的氯仿、乙酸乙酯相萃取物对供试菌均有不同程度的抑菌作用。其中茎叶乙酸乙酯相和种壳的乙酸乙酯相萃取物的抑菌效果较好。茎叶氯仿相无明显抑菌效果。结论,白藓的抑菌活性成分主要存在于乙酸乙酯萃取相中,为白藓抑菌药物的开发提供了理论依据。     

美洲大蠊乙酸乙酯提取物的分离和抑菌活性分析

采用活性追踪法和柱层析法,以金黄色葡萄球菌、大肠杆菌等5种细菌为供试菌种,对美洲大蠊乙酸乙酯提取物进行分离和抑菌试验.研究发现:美洲大蠊乙酸乙酯提取物对供试的革兰氏阳性菌具有一定的抑制作用,其中,对枯草芽孢杆菌的抑菌活性最好;经硅胶柱层析初分离后,从乙酸乙酯提取物获得了9个具有抑菌活性的组分,其中,组分Fr7对5种供试菌均显示了较好的抑菌活性;组分Fr7及其相邻组分Fr8经硅胶和凝胶柱层析进一步分离纯化后,得到了7个具有抑菌活性的不饱和脂肪酸类化合物,均对藤黄微球菌表现出最好的抑菌活性.结果表明:美洲大蠊乙酸乙酯提取物的抑菌活性物质为不饱和脂肪酸类化合物,对供试的革兰氏阳性菌的抑菌活性较强.     

Antimicrobial activity of Omalanthus nervosus

The ethanol extracts of Omalanthus nervosus leaves, stem and root barks, were partitioned (petrol, dichloromethane, ethyl acetate). In respect to crude extracts, all fractions demonstrated broader spectrum and higher levels of antibacterial activity, ethyl acetate fractions being in all cases the more active. No fraction was active against tested moulds.     

Antifungal activity of Cynara scolymus L. extracts

Chloroform, ethanol and ethyl acetate extracts of Cynara scolymus L. leaves, heads and stems were tested for their antifungal activity using the agar-well diffusion assay technique. The leaves extracts and the ethanol fractions were found to be the most effective extract against all the tested organisms.     

Cytotoxicity and antileishmanial activity of Annona muricata pericarp

Hexane, ethyl acetate and methanol extracts of Annona muricata pericarp were tested in vitro against Leishmania braziliensis and L. panamensis promastigotes, and against cell line U-937. The ethyl acetate extract was more active than the other extracts and even of Glucantime used as reference substance. Its fractionation led to the isolation of three acetogenins--annonacin, annonacin A and annomuricin A.     

Antimicrobial activity of Harpullia ramiflora

The methanol extracts of Harpullia ramiflora, leaves, flowers, stem and root barks were partitioned (petrol, dichloromethane, ethyl acetate). In respect to crude extracts, all fractions demonstrated broader spectrum and higher levels of antibacterial activity. The ethyl acetate fraction of the flowers exhibited the highest activity. No activity was shown against the tested moulds.     

Antimicrobial activity of Sternbergia sicula and Sternbergia lutea

n-Hexane, ethyl acetate, ethanolic and aqueous extracts of the bulbs and aerial parts of Sternbergia sicula and Sternbergia lutea were tested for their antimicrobial and antifungal activity.     

穿孔萃取法测定甲醛释放量影响因素的探讨

文章采用穿孔萃取法研究不同影响因素对人造板甲醛释放量检测结果的影响,结果表明：碘量法和光度法测得的甲醛释放量差异显著;甲醛释放量随萃取温度的升高而升高;硫代硫酸钠浓度、乙酸铵浓度、乙酰丙酮用量对测定结果影响显著;乙酸铵试剂用量的微小差别对测试结果影响不明显。     

Anti-microbial activity of Bidens pilosa, Bischofia javanica, Elmerillia papuana and Sigesbekia orientalis.

The ethanol extracts of Bidens pilosa (whole plant), Bischofia javanica (leaves), Elmerillia papuana (root bark) and Sigesbekia orientalis (whole plant) were partitioned (petrol, dichloromethane, ethyl acetate). The crude ethanolic extracts and all the obtained fractions showed a broad spectrum of antibacterial activity, the ethyl acetate fractions and the petrol fraction of E. papuana being the most effective. No activity was observed against the tested moulds.     

Antimicrobial activity of Psychotria microlabastra.

The methanol extracts of leaves, root and stem barks of Psychotria microlabastra showed a broad spectrum of antibacterial activity, that was increased on fractionation (petrol, dichloromethane, ethyl acetate), particularly in the ethyl acetate fractions. None of the extractives showed activity against the tested moulds.     

Implication of limonene and linalyl acetate in cytotoxicity induced by bergamot essential oil in human neuroblastoma cells

Bergamot (Citrus bergamia, Risso et Poiteau) essential oil (BEO) is a widely used plant extract showing anxiolytic, analgesic and neuroprotective effects in rodents; also, BEO activates multiple death pathways in cancer cells. Despite detailed knowledge of its chemical composition, the constituent/s responsible for these pharmacological activities remain largely unknown. Aim of the present study was to identify the components of BEO implicated in cell death. To this end, limonene, linalyl acetate, linalool, γ-terpinene, β-pinene and bergapten were individually tested in human SH-SY5Y neuroblastoma cultures at concentrations comparable with those found in cytotoxic dilutions of BEO. None of the tested compounds elicited cell death. However, significant cytotoxicity was observed when cells were cotreated with limonene and linalyl acetate whereas no other associations were effective. Only cotreatment, but not the single exposure to limonene and linalyl acetate, replicated distinctive morphological and biochemical changes induced by BEO, including caspase-3 activation, PARP cleavage, DNA fragmentation, cell shrinkage, cytoskeletal alterations, together with necrotic and apoptotic cell death. Collectively, our findings suggest a major role for a combined action of these monoterpenes in cancer cell death induced by BEO.     

Antibacterial activity of Cichorium intybus

Antibacterial activity of the water, ethanol and ethyl acetate extracts of Cichorium intybus was investigated. All the tested extracts showed antibacterial activity, the ethyl acetate extract being the most active. Water extract inhibits Agrobacterium radiobacter sp. tumefaciens, Erwinia carotovora, Pseudomonas fluorescens and P. aeruginosa.     

Antimicrobial activity of Evodia elleryana.

The methanol extracts of Evodia elleryana, leaves, stem wood, stem bark, root wood and root bark were partitioned (petrol, dichloromethane, ethyl acetate). All obtained fractions showed a broad spectrum of antibacterial activity, while none were active against tested moulds.     

Antioxidant and antimicrobial activities of Onosma argentatum and Rubia peregrina

The n-hexane-dichloromethane (1:1) extract of the roots of Onosma argentatum and the methanol extract (partitioned between water and chloroform, ethyl acetate and n-butanol, respectively), of the underground parts (roots and rhizomes) of Rubia peregrina were tested in vitro for their antioxidant and antimicrobial activities. The highest antioxidant activity (98%) was observed at 0.1% concentration for the roots of O. argentatum. It was 96% at 0.25% concentration on the ethyl acetate fraction of R. peregrina. O. argentatum extract was effective on Staphylococcus aureus, Bacillus subtilis and Escherichia coli. The ethyl acetate and chloroform fractions of R. peregrina were effective on S. aureus and E. coli, respectively. These two species did not have any antifungal activity.     

Antibacterial activity of Picrasma javanica

The methanol extracts of Picrasma javanica, leaves, seeds, stem and root barks were partitioned (petrol, dichloromethane, ethyl acetate, butanol). All obtained extracts and fractions showed a broad spectrum of antibacterial activity, while none was active against the tested moulds.     

Antimicrobial activity of Viola tricolor herb

The antimicrobial activity of infusion, decoction, ethanol extract and fractions obtained by successive extraction of Viola tricolor herb with dichloromethane, ethyl acetate and methanol was evaluated. The infusion, decoction and ethanol extract were found to be most effective against the tested microorganisms.     

Antimicrobial activity of Clematis papuasica and Nauclea obversifolia.

The methanol extracts of Clematis papuasica leaves and stem bark and of Nauclea obversifolia leaves, stem and root barks showed awide spectrum of antibacterial activity which was increased on fractionation (petrol, dichloromethane, ethyl acetate), the ethyl acetate fractions being in all cases the most effective. None of the extractives was active against tested moulds.     

Molluscicidal activity of some Moroccan medicinal plants

Among 14 plants of Moroccan folk medicine tested for molluscicidal activity, ethyl acetate extract from Origanum compactum and hexane extracts from both Chenopodium ambrosioides and Ruta chalepensis were the most active (LC(90)=2.00, 2.23 and 2.23 mg l(-1), respectively) against the schistosomiasis-transmitting snail Bulinus truncatus.     

Antimicrobial activity of Symplocos cochinensis.

The methanol extracts of leaves, root and stem barks of Symplocos cochinchinensis and their fractions obtained by partition (petrol, dichloromethane, ethyl acetate) were screened for antimicrobial activity. All the crude extracts and fractions showed a broad spectrum of antibacterial activity, that was enhanced on fractionation. None of them showed activity against the tested moulds.