In vitro assessment of antiprotozoal and antimicrobial activities of fractions and isolated compounds from Pallenis hierochuntica

The antiprotozoal and antimicrobial properties of the extract and fractions of the whole plant of Pallenis hierochuntica were investigated against a panel of pathogenic organisms. Fractionation of the methanol extract of the whole plant of Pallenis hierochuntica using reverse-phase chromatography gave 28 fractions and led to the isolation of 2 new bisabolone hydroperoxides, 6,10 β,11-trihydroxy-bisabol-2-ene-1-one (1a), 6,10 α,11-trihydroxy-bisabol-2-ene-1-one (1b) and also 6,10 β-dihydroxy-bisabol-2,11-diene-1-one (2). They were characterised by extensive spectrometric analysis. Anti-infective investigations of the fractions revealed that 22 to 26 possessed significant antimalarial activity against the D6 and W2 strains of Plasmodium falciparum with IC50 = 7.62 – 9.91 µg/mL and 5.49 – 6.08 µg/mL, respectively, and SI>6.0 on average. Fractions 7, 16 to 24 exhibited good activity against Leishmania donovani promastigotes (IC50 = 6.71 – 18.77 µg/mL). Fractions 25 to 28 were active against T. brucei trypomastigotes, 25 being the most potent (IC50 = 4.13 µg/mL). Only 11 to 13 were active against Aspergillus fumigatus (IC50 = 13.406 µg/mL). 1a and 2 were not promising against the organisms tested. 1a and 1b were characterised for the first time

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

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 were evaluated 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 methicillin-resistant 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

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

In vitro Antiplasmodial, Antileishmanial, Antitrypanosomal and Antimicrobial Activities of Crude Extracts of Alchornea cordifolia Leaves

Malaria, leishmaniasis, trypanosomiasis and pathogenic microorganisms infections are a public health burden worldwide. And the rapid development of resistance to the currently used drugs is a significant threat that necessitates the search for new anti-infective agents. Alchornea cordifolia (Schumach. and Thonn) Muell. Arg, family Euphorbiaceae, leaves have been used in folklore medicine to treat different disease conditions such as malaria, fevers, diarrhoea, infertility, wounds, inflammations, diabetes and cancers. This study aimed to assess the in vitro potentials of different crude extracts of the leaves against Plasmodium falciparum, Leishmania donovani (promastigotes, axenic amastigotes, and intracellular amastigotes), Trypanosoma brucei trypomastigotes and a panel of pathogenic bacteria and fungi, using established methods. Crude extracts of the powdered leaf sample of the plant extracted with various solvents were used for the experiment. The results of the antiplasmodial screening revealed that aqueous, methanol and ethanol extracts significantly inhibited two strains of Plasmodium falciparum parasites with IC50 values of 4.885 -18.094 µg/mL. The extracts also showed inhibitory activity against T. brucei trypomastigotes with IC50 of 8.68 -15.71 µg/mL, while chloroform was active against L. donovani blood-stage amastigotes. The extracts were equally effective against Cryptococcus neoformans (IC50 range of 32.258 – 161.853 µg/mL), and only aqueous extract was active against methicillinresistant S. aureus (IC50 199.054 µg/mL). The presence of bioactive compounds in the extracts may be responsible for the observed biological effects, and the plant could be further explored for lead compounds

Jatropha Tanjorensis - Review of Phytochemistry, Pharmacology, and Pharmacotherapy

Jatropha tanjorensis (L) (Fam – Euphorbiaceae), which has been consumed as leafy vegetable and as medicinal plant in Nigeria has shown hematological, antimalarial, antimicrobial, hypoglyceamic, hypolipidemic and antihypertensive activities. This review focuses on valuable knowledge of traditional uses, phytochemistry, and pharmacological activities of Jatopha tanjorensis against some tropical diseases, in order to highlight its therapeutic potentials with a view to integrate it into conventional medical use. Several classes of phytochemical compounds such as the polyphenols, saponins, tannins and alkaloids have been associated with the plant. It has also been shown to possess a wide spectrum of biological activities such as antiplasmodial (antimalarial), anti microbial, antiparasitic, antioxidant, anti-diabetic, antihypertensive, antihyperlipidemic and as remedy for anaemia. The review has thus provided a comprehensive and critical appraisal of the phytochemistry, pharmacology and toxicity of Jatropha tanjorensis in the tropics. Based on the findings of this work, future study on the phytochemistry and chemical constituents in relation to certain other biological activities are required to fully understand the phytochemical and complex pharmacological effect of the plant specie. Further work to isolate active compounds from the plant is also necessary.Keywords: Jatropha tanjorensis, Pharmacology, Phytochemistry, medicinal usesJournal of Pharmaceutical and Allied Sciences, Vol. 10 No. 3 (2013

Isolation of antileishmanial, antimalarial and antimicrobial metabolites from Jatropha multifida

Objective: To investigate the antileishmanial, antimicrobial and antimalarial activities of the pure metabolites from Jatropha multifida used in African ethnomedicine. Methods: The methanolic stem bark extract of Jatropha multifida used in Nigerian folk medicine as remedy against bacterial infections was subjected to column chromatography and HPLC analyses to obtain three known metabolites, microcyclic lathyrane diterpenoids (1-3). Structures were confirmed by comparison of 1D and 2D spectral data with literature. Results: The three compounds exhibited inhibition of antileishmanial, antimalarial and antimicrobial actions against the tested organisms with compouds 2 and 3 active against Cryptococcus neoformans at IC50 of 8.2 and 8.7 μg/mL, respectively. Conclusions: The research lends support to the ethnomedicinal use of the plant in combating microbial infections, leishmaniasis and malarial infections

Aurones as Antidiabetic Agents and Their Prebiotic Activities

Cyperus conglomeratus has been utilized in traditional medicine as an emollient, diuretic, analgesic, anthelmintic, and for other diseases. Furthermore, several biological activities have been reported for the plant extract and the isolated metabolites. The chromatographic investigation of an ethyl acetate extract of the aerial parts led to the isolation of three aurone derivatives (1–3) from the plant for the first time. Their structures were identified as aureusidin (1), aureusidin-4-methyl ether (2), and 5-methyl aureusidin (3) using 1D and 2D NMR techniques, along with mass spectrometry. The compounds were tested for their inhibitory activities against enzymes vital in metabolic diseases, especially diabetes, such as α-amylase, α-glucosidase, and glycogen phosphorylase. The results were expressed as percentage inhibition. The inhibitory activity of aurones against the tested enzymes was also analyzed by computational docking studies to provide a rational explanation for the observed results. The tested compounds formed stable interactions in terms of hydrogen bonding and hydrophobic interaction with the active site residues of the tested enzymes, and the results are in agreement with those of the in vitro antidiabetic activity. The compounds were also evaluated for their ability to support the growth and viability of beneficial bacteria in terms of prebiotic activities using two species, Lacticaseibacillus paracasei and Lacticaseibacillus rhamnosus, through the determination of prebiotic activity scores (Pscore). The findings of this study showed that C. conglomeratus is a potential natural source of bioactive agents. There is, however, a need for in vivo testing to evaluate this plant’s efficacy for developing new drug entities in the future

Mosquitocidal Activity of the Methanolic Extract of <em>Annickia</em><em> chlorantha</em> and Its Isolated Compounds against <em>Culex pipiens</em>, and Their Impact on the Non-Target Organism Zebrafish, <em>Danio rerio</em>

In this study, the crude extract and its isolated compounds from the stem bark of Annickia chlorantha were tested for their larvicidal, developmental, and repellent activity against the mosquito vector, Culex pipiens, besides their toxicity to the non-target aquatic organism, the zebrafish (Danio rerio). The acute larvicidal activity of isolated compounds; namely, palmatine, jatrorrhizine, columbamine, β-sitosterol, and Annickia chlorantha methanolic extract (AC), was observed. Developmentally, the larval duration was significantly prolonged when palmatine and β-sitosterol were applied, whereas the pupal duration was significantly prolonged for almost all treatments except palmatine and jatrorrhizine, where it shortened from those in the control. Acetylcholinesterase (AChE) enzyme showed different activity patterns, where it significantly increased in columbamine and β-sitosterol, and decreased in (AC), palmatine, and jatrorrhizine treatments, whereas glutathione S-transferase (GST) enzyme was significantly increased when AC methanolic extract/isolated compounds were applied, compared to the control. The adult emergence percentages were significantly decreased in all treatments, whereas tested compounds revealed non-significant (p > 0.05) changes in the sex ratio percentages, with a slight female-to-male preference presented in the AC-treated group. Additionally, the tested materials revealed repellence action; interestingly, palmatine and jatrorrhizine recorded higher levels of protection, followed by AC, columbamine, and β-sitosterol for 7 consecutive hours compared to the negative and positive control groups. The non-target assay confirms that the tested materials have very low toxic activity compared to the reported toxicity against mosquito larvae. A docking simulation was employed to better understand the interaction of the isolated compounds with the enzymes, AChE and GST. Additionally, DFT calculations revealed that the reported larvicidal activity may be due to the differing electron distributions among tested compounds. Overall, this study highlights the potential of A. chlorantha extract and its isolated compounds as effective mosquitocidal agents with a very low toxic effect on non-target organisms