Phytochemical analysis and antioxidant evaluation of lemon grass (Cymbopogon citratus DC.) Stapf leaves

Cymbopogon citratus commonly called lemon grass is claimed to possess diverse medicinal value among different cultures. The present study determined the phytochemicals and evaluated the antioxidant potential of Cymbopogon citratus leaves. The phytochemical and proximate analysis of the powdered leaves were carried out using standard methods. The antioxidant activity of the crude methanol extract and its fractions (n-hexane, ethyl acetate and chloroform) was evaluated using 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging and ferric reducing antioxidant power (FRAP) assays. The total phenolic and flavonoid contents were assessed using the Folin-Ciocalteu and aluminium chloride colorimetric methods, respectively. The phytochemical analysis revealed the presence of carbohydrates, reducing sugars, saponins, tannins, flavonoids and other phenolics compounds. The moisture, ash, fat, crude fibre, crude protein, water soluble ash and acid insoluble ash contents were 13.00%, 7.63%, 2.44%, 29.40%, 4.45%, 6.13% and 4.00%, respectively. Among the extract and fractions tested, the ethyl acetate fraction exhibited the highest antioxidant activity. The ethyl acetate fraction also had the highest phenolic and flavonoid contents. There was a strong relationship between the polyphenolic content and antioxidant activity of the extract and fractions with a coefficient of determination (r²) of 0.889 and 0.920 for total phenols and total flavonoids, respectively. The present study showed that the leaves of Cymbopogon citratus especially the ethyl acetate fraction possess good antioxidant activity and could serve as potentially source of natural antioxidants.Keywords: Medicinal plants, Lemon grass, Cymbopogon citratus, Phytochemicals, antioxidant

A preliminary study on the antimicrobial activities and gas chromatography-mass spectrometry (GC-MS) analysis of the ethyl acetate extract of Dennettia tripetala G. Baker seeds

The study investigated the antimicrobial properties and the chemical composition of ethyl acetate extract of Dennettia tripetala (pepper fruit) seeds. Crude extract obtained by maceration of pulverized seeds in ethyl acetate was evaluated for antimicrobial activity against Escherichia coli, Staphylococcus aureus, Klebsiella aerogenes, Pseudomonas aeruginosa, Bacillus subtilis, Candida albicans and Aspergillus niger using standard agar-well diffusion method. GC-MS method was used to determine the chemical constituents of the extract. The extract was oily, yellowish-brown with a yield of 1.66 % and had activity against most of the test microorganisms, with inhibition zone diameters ranging between 10 to 25 mm. About 41 chemical constituents were present in the extract with formic acid methyl esters and fatty acids accounting for 57.23 and 18.49 % respectively. Ethyl acetate extract of Dennettia tripetala seeds possessed antimicrobial activity against bacteria but not fungi. The observed activity may be due to the presence of formic and fatty acid esters in the seed. The study further established a scientific proof for the traditional use of Dennettia tripetala seed extracts in treating microbial infections. &nbsp

Biological Activities of a Macrocyclic Diterpenoid Isolated from the Roots of Jatropha gossypiifolia

Background: Extracts of Jatropha gossypiifolia L. (Euphorbiaceae) have been used ethnomedicinally for the treatment of various ailments. The present study was to investigate the biological activity of Jatrophone, a macrocyclic diterpenoid isolated from the roots of J. gossypiifolia. Methods: Phytochemical studies followed by chromatographic separation of the methanol root bark extract led to the isolation of a macrocyclic diterpenoid, identified as jatrophone on the basis of NMR and mass spectra data and by comparison with literature. The isolated compound, jatrophone was evaluated for its antiprotozoal activity against Plasmodium falciparum strains [D6 (chloroquine sensitive) and W2 (chloroquine-resistant)], Leishmania donovani and Trypanosoma brucei. The antimicrobial activity was evaluated against type culture of selected fungi and bacteria. Analgesic activity was investigated using the acetic acidinduced writhing and hot plate model in mice. The cytotoxicity was assessed against VERO cell line (monkey kidney fibroblast) using neural red uptake method. Results: Jatrophone showed significant antiplasmodial and antileishmanial activities with IC50 of 0.55, 0.52 and < 0.4 µg/mL for P. falciparum (D6 strain), P. falciparum (W2 strain) and L. donovani respectively. Compound 1 was highly cytotoxic to VERO cell line with IC50 of 0.43 µg/mL. Jatrophone demonstrated significant analgesic effect with a percentage reduction in acetic acid-induced writhes of 54.03% and 66.35% at 5 and 10 mg/kg respectively. No significant antimicrobial activity was observed against the test organisms. Conclusion: The present study has shown that jatrophone possess antimalarial, antileishmanial, and analgesic activitie

Antimicrobial activity of ethyl acetate extract of Citrullus lanatus seeds

Purpose: To determine the antimicrobial activity and chemical constituents of ethyl acetate extract of Citrullus lanatus seeds.Methods: Antimicrobial activity of the ethyl acetate extract of the seeds of C. lanatus was evaluated against Staphylococus aureus ATCC 25923, Escherichia coli ATCC 25922, Bacillus subtilis NCTC8236, Pseudomonas aeruginosa ATCC 10145 and Candida albicans ATCC 24433 using standard microbiological method. Chemical constituents of the extract were determined with Gas chromatography and mass spectrometry (GC MS) systems.Results: An oily, yellowish orange coloured extract with a yield of 18.7 % was obtained. The extract inhibited the growth of all test microorganisms at minimum inhibitory concentration range of 0.313 -2.5 mg/mL and minimum bactericidal concentration of 0.313-5 mg/mL. GC MS profile of the extract showed the presence of oleic acid (31.22 %), saturated fatty acid (23.85 %) and gamma tocopherol (8.79 %). Other organic compounds accounted for 36.16 % of the extractConclusion: Ethyl acetate extract of the seeds of Citrullus lanatus has antimicrobial effect against some Gram positive and Gram negative bacteria as well as C. albicans. Twenty-one compounds including fatty acids, hexamethyl-2-ethylacridine, gamma tocopherol and methylphthalate have been identified in the seeds.Keywords: Citrulluslanatus seeds, ethyl acetate extract, antimicrobial activit

Evaluation of three medicinal plant extracts against Plasmodium falciparum and selected microganisms

Background: A great revival of scientific interests in drug discovery has been witnessed in recent years from medicinal plants for health  maintenance. The aim of this work was to investigate three Nigerian  medicinal plants collected in Nigeria for their in vitro antiplasmodial and antimicrobial activities.Materials and Methods: Extracts obtained from parts of Persea americana, Jatropha podagrica and Picralima nitida and their fractions wereevaluated for in vitro antiprotozoal and antimicrobial activity.Result: The methanol extract of P. nitida demonstrated activity against chloroquine-sensitive and chloroquine-resistant P. falciparum clones with IC50 values of 6.3 and 6.0 µg/mL, respectively. Methanol and chloroform extracts of P. americana seed showed antifungal activity against Cryptococcus neoformans IC50 less than 8 and 8.211 µg/mL respectively. Finally, the petroleum ether extract of P. americana had activity against methicillinresistant Staphylococcus aureus (MRSA) with an IC50 value of 8.7 µg/mL.Conclusion: The study revealed the antibacterial and antiplasmodial activities of the plants extracts at the tested concentrations.Keywords: Antifungal, Antibacterial, Persea americana, Picralima nitida, Jatropha podagrica, Plasmodium falciparu

Identification of Compounds and Insecticidal Activity of the Root of Pride of Barbados (Caesalpinia Pulcherrima L)

Caesalpinia pulcherrima (Caesalpiniaceae) is an ornamental plant with several ethnomedicinal uses. The present study was designed to investigate the brine shrimp cytotoxicity and insecticidal activity of oil obtained from C. pulcherrima root. The powdered root was extracted with methanol and then defatted with petroleum ether (40-60oC) to obtain a viscous oil. The oil was investigated for its brine shrimp cytotoxicity and insecticidal activity in vitro. The chemical constituents were identified by Gas chromatography-Mass spectrometry. The oil showed significant lethal effect against Artemia salina (Brine shrimp) with LC50 of 23.85 μg/mL and mild insecticidal activity against Tribolium castaneum and Callosbruchus analis with percentage mortality of 20% and 40% respectively at 1 mg/cm2. GC-MS analysis identified 37 compounds mainly steroids, terpenoids and fatty acids.Keywords: Caesalpinia pulcherrima, chemical constituents, cytotoxicity, insecticidal activity

Isolation of Diterpenoids from Jatropha podagrica against Hepatitis C virus

One new lathyrane diterpenoid, Jatropodagrene (1) along with three known compounds have been isolated from the root bark of Jatropha podagrica. The structure of the new compound was established from its 1D and 2D NMR spectra and in comparison with data reported in previous literatures. Compound 1 was highly cytotoxic (98.86% inhibition) to the HCV virus, while compounds 2 (EC50, EC90, CC50 5.8, 33.1, 22.6 μg/mL, respectively) and 3 displayed significant anti HCV activity. This is the first report of the anti hepatitis C virus activity of lathyrane skeleton and J. podagrica.Keywords: Jatropha podagrica; medicinal plant; hepatitis C virus; extract; pure compound

Total Phenol amd Flavonoid contents of Crude Extract and Fractions of Picralima Nitida root bark TH. and H. Durand (Apoceanaceae)

Phenolic compounds are numerous in plants and are essential part of human diet. Picralima nitida has been extensively used in African folk medicine especially in West Africa. The present study evaluated the total phenolic and flavonoid contents of the extract and fractions of Picralima nitida. The methanol extracts of P. nitida root bark and its fractions were evaluated for their phenolic contents using the Folin-Ciocalteu’s method. The total flavonoid contents were also determined using standard method. Statistical significance was established by one-way analysis of variance (ANOVA) and differences between means were determined using Duncan’s multiple range (DMR) test. The results revealed that the crude methanol extract has a significantly higher concentration of total phenol and flavonoid compared to the fractions (P < 0.05). The total phenolic and flavonoid contents for the crude methanol extract were 94.92 ± 9.50 mg gallic acid equivalent (GAE)/g extract and 46.46 ± 3.30 mg quercetin equivalent (QE)/g extract respectively. The result obtained demonstrated that Picralima nitida root bark extract has a high content of phenol and method of extraction could be a major determinant of polyphenolic content.Keywords: Phenolic content, flavonoid, extraction, Picralima nitidaJournal of Pharmaceutical and Allied Sciences Vol. 9 No. 3 (2012

Determination of physico-chemical parameters, acute toxicity and heavy metals profile of Eleusine coracana seeds

Medicinal plants have been used for a very long time in the prevention and treatment of many ailments plaguing mankind. They contain phytochemicals and minerals which contribute to the pharmacological activities they exhibit. This study was carried out to investigate the proximate analysis, phytochemical and mineral constituents of the powdered seed of Eleusine coracana as well as to determine the acute toxicity profile of the powdered seeds. The results obtained showed that the seeds have low percentage moisture content 0.38 ± 0.14% (which is beneficial for longer shelf life); Total Ash value 2.23 ± 0.13 %, Acid Insoluble Ash value 0.76 ± 0.05). The phytochemical constituents present are alkaloids, saponins, terpenoids, flavonoids, carbohydrates, proteins, phenols, alkaloids and reducing sugars. The heavy metals and other mineral analysis showed that heavy metals such as; cadmium (Cd) and nickel (Ni) were absent while lead was detected in a negligible concentration of 0.01±0.00 ppm. The essential and nonessential minerals contents of the sample detected (calcium, iron, potassium, sodium, magnesium, copper, zinc and chromium) were within the WHO specified limits. The acute toxicity profile showed that at a dose of 5000 mg/kg body weight the crude extract of Eleusine coracana did not produce any toxic effect and no mortality was observed even after 14 days of observation. The rich properties and phytoconstituents of Eleusine coracana seeds could be responsible for its nutritional status. The seeds can further be explored for pharmaceutical leads through bioassay-guided isolation and characterization of the active principles and for use as nutraceutical supplements. Keywords: Antioxidants, Phytoconstituents, Eleusine coracana, Ash values, free radical

Antiproliferative and apoptotic activities of Cola lepidota against estrogen receptor positive breast cancer cells

The stem bark, seed, roots and leaves of Cola lepidota have been used for various health conditions in Nigeria folk medicine including treatment of cancer related ailments. The study evaluated the antiproliferative and apoptotic effects of extracts of the leaves and stem bark on breast cancer (MCF-7) cell line. Powdered stem bark and leaves were extracted with methanol and concentrated in vacuo. Extracts were partitioned with petroleum ether, chloroform and ethyl acetate successively. The extract and fractions were screened for antiproliferative and apoptotic activities using flow cytometry. The methanol leaf extract (CLL-M) demonstrated significant (p < 0.01) antiproliferative activity against estrogen receptor positive breast cancer cells (26.09 %), while the chloroform fraction of the stem extract (CLS-CH) showed significant (p < 0.001) apoptotic activity.The study lends support to the ethnomedicinal use of Cola lepidota and indicates the potential of the plant as source of natural anticancer agent.Keywords: apoptosis, proliferative, anticancer, Cola lepiota, extrac