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 ß,11-trihydroxy-bisabol-2-ene-1-one (1a), 6,10 α,11-trihydroxy-bisabol-2-ene-1-one (1b) and also 6,10 ß-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.

Mosquitocidal Activity of the Methanolic Extract of Annickiachlorantha and Its Isolated Compounds against Culex pipiens, and Their Impact on the Non-Target Organism Zebrafish, Danio rerio.

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, ß-sitosterol, and Annickia chlorantha methanolic extract (AC), was observed. Developmentally, the larval duration was significantly prolonged when palmatine and ß-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 ß-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 ß-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.

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.

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.

Anticancer activity of five forest crops used in African folklore: antiproliferative and pro-apoptotic effects.

Acalypha wilkesiana, Caesalpinia bonduc, Jatropha multifida, Momordica charantia and Picralima nitida used in African folklore for treating cancer were investigated. All extracts except J. multifida resulted in no significant alteration in cell cycle distribution and apoptosis in MCF-7 and BT-20. The J. multifilda (JMR-Ch) caused cell cycle arrest at G1 checkpoint and apoptosis in MCF-7. Slight changes in the integrin expression of MCF-7 after treatment with 1 and 10 µg/mL of JMR-Ch were observed. Fluorescence-activated confocal microscopy shows changes in cell morphology and ß1 integrin localisation within MCF-7 cells after exposure to 10 and 25 µg/mL of JMR-Ch. JMR-Ch (1 µg/mL) treatment resulted in time-dependent decrease in cell acidification and respiration in MCF-7 cells and a time-dependent decrease in BT-20 cell respiration, while in MCF-10A, there was an enhancement of acidification. These results revealed the probable application of JMR-Ch in cancer therapy.