Antioxidant and antiglycation properties of two mango (Mangifera indica L.) cultivars from Senegal

Objective:To evaluate the total phenolic contents,antioxidant and antigiycation activities of leaves,barks,roots and kernels from two cultiivars of Mangifera indica (Anacardiiaceae).Method:Total phenolic contents were determined by using Folin-Ciocalteu's method.The antioxidant activities were assessed by three different protocols including DPPH,oxygen radical absorbance capacity and iron (Ⅱ) chelation assays.In addition,in vitro bovine serum albumin/D-ribose assay was chosen to evaluate the antiglycation properties of the extracts.Results:All the investigated extracts were found to contain high level of total phenols as well as potent antioxidant activities.Kernel extracts showed the highest total phenol contents and DPPH radical scavenging activities whereas higher oxygen radical absorbance capacity values were observed for leave,root and bark extracts.Besides,extracts from leaves,roots and barks from both cultivars exhibited potent inhibitory effects against the formation of advanced glycation end products,with IC50 values lower than the standard positive control aminoguanidine.Conclusions:The potent antigiycation and antioxidative activities of these two Mangifera indica cultivars suggest a possible role in targeting aging,diabetic complications and oxidative stress related diseases.

Antifungal and anthelmintic activities of Cleistopholis patens (Annonaceae).

Basic CH2Cl2 extract of the trunk bark of Cleistopholis patens (Annonaceae) exhibited antifungal activities against Candida albicans, C. parapsilosis, and C. glabrata using an agar well-diffusion assay method. Bioassay-guided fractionation of the extract led to the isolation of 8-hydroxysampangine. The methanolic extract displayed anthelmintic activity against Rhabditis pseudoelongata. Purification of the neutral CH2Cl2 extract yielded bornyl-p-transcoumarate and bornyl-p-cis-coumarate.

Separation of protoberberine quaternary alkaloids from a crude extract of Enantia chlorantha by centrifugal partition chromatography.

High-performance centrifugal partition chromatography (HPCPC) has been successfully applied to the separation of four protoberberine quaternary alkaloids, namely palmatine, jatrorrhizine, columbamine and pseudocolumbamine, from a methanolic extract (M1, 1.47 g) of Enantia chlorantha Oliver stem bark. For their isolation, two successive biphasic solvent systems composed of dichloromethane-methanol-water (48:16:36, v/v) were selected. The aqueous-rich phase was the stationary phase and the organic-rich phase was the mobile phase. The first system, containing potassium perchlorate, allowed to isolate 600 mg of palmatine, and to obtain 146 mg of a mixture (M2) containing only jatrorrhizine, columbamine and pseudocolumbamine. The second biphasic system, prepared with water alkalinized with sodium hydroxide, was employed to isolate the M2 components. This system applied to the purification of 70 mg of M2 allowed to obtain 16 mg ofjatrorrhizine and 13 mg of columbamine. To obtain pseudocolumbamine (16 mg), the elution mode was reversed, the aqueous-rich phase becoming the mobile phase, and the organic-rich phase becoming the stationary one. Analytical reversed-phase high-performance liquid chromatography, NMR, high-resolution mass spectrometry and UV spectrometry were used to verify the identity and the purity of the isolated compounds.

Klaivanolide, an antiprotozoal lactone from Uvaria klaineana.

Bioguided-fractionation of a CH(2)Cl(2) extract of the stems of Uvaria klaineana (Annonaceae) led to isolation of klaivanolide, a novel bisunsaturated 7-membered lactone (5-acetoxy-7-benzoyloxymethyl-7H-oxepin-2-one), together with benzyl benzoate. Klaivanolide showed potent in vitro antileishmanial activity against both sensitive and amphotericin B-resistant promastigote forms of Leishmania donovani with IC(50) values of 1.75 and 3.12 microM, respectively. The compound also showed in vitro trypanocidal activity against trypomastigote forms of Trypanosoma brucei brucei GVR 35. Its structure was established by 1D and 2D NMR and other spectroscopic techniques.