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AbstractThe emergence of varying levels of resistance to currently available antimalarial drugs significantly threatens global health. This factor heightens the urgency to explore bioactive compounds from natural products with a view to discovering and developing newer antimalarial drugs with novel mode of actions. Therefore, we evaluated the inhibitory effects of sixteen phytocompounds from Cymbopogon citratusleaf extract against Plasmodium falciparumdrug targets such as P. falciparumcircumsporozoite protein (PfCSP), P. falciparummerozoite surface protein 1 (PfMSP1) and P. falciparumerythrocyte membrane protein 1 (PfEMP1). In silicoapproaches including molecular docking, pharmacophore modeling and 3D-QSAR were adopted to analyze the inhibitory activity of the compounds under consideration. The molecular docking results indicated that a compound swertiajaponin from C. citratusexhibited a higher binding affinity (−7.8 kcal/mol) to PfMSP1 as against the standard artesunate-amodiaquine (−6.6 kcal/mol). Swertiajaponin also formed strong hydrogen bond interactions with LYS29, CYS30, TYR34, ASN52, GLY55 and CYS28 amino acid residues. In addition, quercetin another compound from C. citratusexhibited significant binding energies −6.8 and −8.3 kcal/mol with PfCSP and PfEMP1, respectively but slightly lower than the standard artemether-lumefantrine with binding energies of −7.4 kcal/mol against PfCSP and −8.7 kcal/mol against PfEMP1. Overall, the present study provides evidence that swertiajaponin and other phytomolecules from C. citratushave modulatory properties toward P. falciparumdrug targets and thus may warrant further exploration in early drug discovery efforts against malaria. Furthermore, these findings lend credence to the folkloric use of C. citratusfor malaria treatment.Communicated by Ramaswamy H. Sarma

The in vitroantimicrobial and in vivoheavy metal abatement properties of aqueous extracts of Garcinia kolaHeckel (bitter cola) were investigated using opportunistic pathogens and Wistar rats as experimental models. A marked inhibitory activity against Aspergillus niger, Aspergillus flavusand Candida albicanswas recorded at 100mg/ml of the crude relative to ketoconozole and fluconazole drugs. Similarly, different concentrations (25mg/ml, 50mg/ml and 100mg/ml) of the crude extracts of bitter cola inhibited species of Escherichia coliand Pseudomonas aeruginosaalmost as effectively as the control drug of streptomycine used. Chronic lead acetate poisoned wistar rats in groups B, C, D, E exposed to G. kolasupplemented feed and water ad libitumshowed variable decrease in the serum alkaline phosphatase level while aspartate and alanine aminotransferases level reduces in C and D groups compared to the negative control group. The kidney biomarkers; serum creatinine and urea concentrations were not significantly different at P≤0.05 for rat groups C, D, E when compared with the positive and negative control groups respectively. Mild infiltration and cell distortion were observed in the liver and kidney sections of the rats exposed to uncoated bitter cola supplemented feed while suggesting an overriding effect from the nut coats. The study reaffirms the medicinal potential of coated and uncoated bitter cola to act as abatement of lead toxicity and alternative antimicrobial. Furthermore, G. kolacould be a double-edged drug for the spontaneous amelioration of lead toxicity and secondary infections due to lead poisoning.

In Nigeria, Annona muricataL. has been used to treat a variety of ailments. The mechanism of the antimalarial activity of ethanolic leaf extract of Annona muricata(EEAML) was investigated using both an in vivo and an in silico approach. The experimental mice were divided into five groups: A-F. The mice in groups B-F were inoculated with Plasmodium bergheiNK-65 and treated accordingly. Groups A and B are the negative and positive controls (infected and untreated), respectively. Group C received 10 mg/kg chloroquine (standard drug), whereas groups D-F received 100, 200, and 300 mg/kg body weight of the extract orally respectively. The mice were euthanized eight days after infection, and their liver and blood were collected and used in biochemical tests. Molecular docking was performed using the extract's HPLC compounds and Plasmodium falciparumproteins. In the suppressive, prophylactic, and curative tests, there was a significant decrease (p < 0.05) in parasitemia levels in groups treated with the extract compared to the positive control and standard drug. When compared to the positive control, there was a significant (p < 0.05) reduction in liver MDA, total cholesterol, and total triglyceride levels. The binding energies of luteolin and apigenin-pfprotein complexes were significantly (p < 0.05) higher compared to their respective references. The anti-plasmodial activity of the extract may result from its hypolipidemic effect, which deprives the parasite of essential lipid molecules needed for parasite growth, as well as from the inhibitory effects of apigenin and luteolin on specific proteins required for the Plasmodiummetabolic pathway.

Conventional drugs, as means of alternative medicine, have been in use in the Asian andAfrican nations and some developed countries for the treatment of ailments and cure of diseases.Objective: Puerarin, a naturally occurring isoflavone in numerous plants, is one of the conventionalmedication that possess anti-inflammatory and immunoregulatory properties for the treatment ofcardiac illnesses, osteonecrosis, Parkinsons disease, Alzheimers disease, and other circulatoryconditions. Puerarin is extensively distributed in numerous organs including the kidney, mammarygland, femur, tibia, stomach, liver, pancreas, brain, and lungs, but at a low rate because of its pooravailability. However, when co-administered with compounds like gastrodin that can convey it intothe cell, it shows a wide range of pharmacological properties, including antioxidant, antidiabetic,antimicrobial, antiviral, anti-inflammatory, anticancer, anti-Alzheimers, hepatoprotective, and neuroprotectiveactivity. The biotransformation process of puerarin showed that it is well metabolizedwith daidzein, being the main hydrolyzed product. Puerarin is well tolerated in the body with adosage of up to 250 mg/kg per day, does not initiate any toxic side effects but rather shows a widerange of beneficial and pharmacological properties.