Anti-trypanosomal activity of nigerian plants and their constituents.

African trypanosomiasis is a vector-borne parasitic disease causing serious risks to the lives of about 60 million people and 48 million cattle globally. Nigerian medicinal plants are known to contain a large variety of chemical structures and some of the plant extracts have been screened for antitrypanosomal activity, in the search for potential new drugs against the illness. We surveyed the literatures on plants and plant-derived products with antitrypanosomal activity from Nigerian flora published from 1990 to 2014. About 90 plants were identified, with 54 compounds as potential active agents and presented by plant families in alphabetical order. This review indicates that the Nigerian flora may be suitable as a starting point in searching for new and more efficient trypanocidal molecules.

Molecular modeling of potential anticancer agents from African medicinal plants.

Naturally occurring anticancer compounds represent about half of the chemotherapeutic drugs which have been put in the market against cancer until date. Computer-based or in silico virtual screening methods are often used in lead/hit discovery protocols. In this study, the "drug-likeness" of ~400 compounds from African medicinal plants that have shown in vitro and/or in vivo anticancer, cytotoxic, and antiproliferative activities has been explored. To verify potential binding to anticancer drug targets, the interactions between the compounds and 14 selected targets have been analyzed by in silico modeling. Docking and binding affinity calculations were carried out, in comparison with known anticancer agents comprising ~1,500 published naturally occurring plant-based compounds from around the world. The results reveal that African medicinal plants could represent a good starting point for the discovery of anticancer drugs. The small data set generated (named AfroCancer) has been made available for research groups working on virtual screening.

Biodegradable microspheres based on gelatin-porcine mucin admixtures: in vitro and in vivo delivery studies.

Soluble mucus glycoprotein (S-mucin) processed from the small intestines (ileal region) of freshly slaughtered pigs via homogenization, dialysis, centrifugation and lyophilization and their admixtures with type B gelatin were used to prepare cefaclor-loaded microspheres by the emulsification-crosslinking method. The microspheres were evaluated for the in vitro delivery of cefaclor in both simulated intestinal fluid (SIF) without pancreatin (pH 7.4) and simulated gastric fluid (SGF) without pepsin (pH 1.2). Results obtained indicated that the microspheres formulated were highly mucoadhesive and that release of cefaclor in both release media was non-Fickian and was much higher and more rapid in SGF than in SIF and from microspheres based on gelatin alone when compared to those based on gelatin-procine mucin admixtures. The mean area under the plasma level versus time curves (AUC) was shown to be dependent on the formulation with values of 172.3 mug.h/ml for the control, 278.5 mug.h/ml for microspheres based on gelatin only and 353.0 mug.h/ml for microspheres formulated with equal parts of gelatin and mucin indicating that the rectal route may provide a therapeutically viable alternative to the oral route for the delivery of cefaclor. Further indications also emerged of a possibility of site-specific delivery of cefaclor to the small intestine through a careful selection of gelatin type and porcine mucin admixtures prior to formulation of the microspheres. On the whole, the inclusion of S-mucin in the composition of the microspheres had an enhancer effect on the release and rectal bioavailability of cefaclor which may be exploited in the design of a rectal delivery system of the drug.

Evaluation of snail mucin motifs as rectal absorption enhancer for insulin in non-diabetic rat models.

The use of snail mucin motifs as rectal absorption enhancer for insulin has been evaluated. The mucin motifs were extracted from the giant African snail Archachatina marginata by differential precipitation with acetone. The mucin motifs were found to have a molecular weight of 5780 Da and an isoelectric point of 3.4. At the concentrations evaluated, the mucin exhibited rectal absorption enhancing property for the administration of insulin in rats. The % basal blood glucose level of the rats that received the batch of suppositories containing no mucin were consistently above 100% except at the ninetieth minute when it came down slightly to 97.2%. Rats dosed with the batch containing 7%w/w suppositories showed the greatest blood glucose reduction with mean % basal blood glucose concentration of 61.2%. Batches of the suppository containing 5% and 7% mucin showed more marked and consistent lowering in blood glucose concentration than the other batches containing lower amounts of the rectal absorption enhancer. The batch with 7% mucin reduced the basal glucose level to 44% within 2 h of administration of the glycero-gelatin suppository loaded mucin.

Thermodynamic consideration of the charge transfer interaction of the donor: acceptor type between chloranilic acid and haloperidol.

The thermodynamic parameters of the charge transfer complex between chloranilic acid and haloperidol were studied. Haloperidol in pure form and in dosage form was assayed in this study. The method was based on charge transfer complex formation between the drug, which acted as an n-donor, and chloranilic acid, which acted as a pi acceptor in a non aqueous solvent. The complex stoichiometry was found to be 1:2 (haloperidol: chloranilic acid) with the maximum absorption band at a wavelength of 576 nm. The complex obeyed Beer's law. The thermodynamic parameters investigated included stability constant, molar absorptivity, free energy change, enthalpy, and entropy. The method was successfully applied in the analysis of commercially available haloperidol tablets without interference from its excipients, with good precision and reproducibility, compared with the official assay method (non aqueous titration) described for haloperidol in the compendium.

Bioadhesive delivery of metformin using prosopis gum with antidiabetic potential.

The antidiabetic properties of prosopis gum alone and as a bioadhesive base for the delivery of metformin are presented. The bioadhesive value of the gum was commensurate with those of Carbopol 974-P and sodium carboxymethyl cellulose (NaCMC). The release of the drug was higher from prosopis gum based bioadhesive formulations than from NaCMC and Carbopol 974-P products. This was shown by the shorter time required to reach t(50) (the time required for 50% of the drug to be released) or t(20) (time required for 20% of the drug to be released) for the release of metformin. The gum showed moderate antidiabetic properties when used alone. In combination with metformin in a bioadhesive form, the glucose lowering effect was found to be synergistic. The areas under the plasma drug concentration vs. time curves (AUCs) for the bioadhesive combinations were similar to those of the drugs alone in an aqueous system. This shows that the gum did not interfere with absorption of the incorporated drug. However, the areas under the effect vs. time curves (AUECs) were much higher when combined in a bioadhesive form than with the drug alone. The AUCs obtained with NaCMC based bioadhesive formulations were relatively smaller than those of metformin in an aqueous system and the combinations of metformin and prosopis gum.