Polyphenol content and antioxidant activity of fourteen wild edible fruits from Burkina Faso

A total of fourteen (14) species of wild edible fruits from Burkina Faso were analyzed for their phenolic and flavonoid contents, and their antioxidant activities using the DPPH, FRAP and ABTS methods. The data obtained show that the total phenolic and total flavonoid levels were significantly higher in the acetone than in the methanol extracts.Detarium microcarpum fruit had the highest phenolic and the highest flavonoid content,followed by that of Adansonia digitata, Ziziphus mauritiana, Ximenia americana and Lannea microcarpa. Significant amounts of total phenolics were also detected in the other fruit species in the following order of decreasing levels: Tamarindus indica > Sclerocaryabirrea > Dialium guineense > Gardenia erubescens > Diospyros mespiliformis > Parkiabiglobosa > Ficus sycomorus > Vitellaria paradoxa. Detarium microcarpum fruit also showed the highest antioxidant activity using the three antioxidant assays. Fruits with high antioxidant activities were also found to possess high phenolic and flavonoid contents. There was a strong correlation between total phenolic and flavonoid levels and antioxidant activities.     

Antioxidant, xanthine oxidase and lipoxygenase inhibitory activities and phenolics of Bauhinia rufescens Lam. (Caesalpiniaceae)

An aqueous acetone extract of the stem with the leaves of Bauhinia rufescens and its fractions were analysed for their antioxidant and enzyme-inhibitory activities, as well as their phytochemical composition. For measurement of the antioxidant activities, the 2,2-diphenyl-1-picrylhydrazyl, 2,2'-azinobis(3-ethylbenzoline-6-sulphonate) and the ferric-reducing methods were used. The results indicated that the aqueous acetone, its ethyl acetate and n-butanol fractions possessed considerable antioxidant activity. Further, the xanthine oxidase and lipoxygenase inhibitory assays showed that the n-butanol fraction possessed compounds that can inhibit both these enzymes. In the phytochemical analysis, the ethyl acetate and the n-butanol fractions of the aqueous acetone extract were screened by HPLC-MS for their phenolic content. The results indicated the presence of hyperoside, isoquercitrin, rutin quercetin, quercitrin, p-coumaric and ferulic acids in the non-hydrolysed fractions. In the hydrolysed fractions, kaempferol, p-coumaric and ferulic acids were identified.     

Mutagenic effect, antioxidant and anticancer activities of six medicinal plants from Burkina Faso

The antiproliferative activities of six medicinal plant extracts from Burkina Faso were evaluated in order to justify their traditional use for the treatment of cancer. The SOS chromotest method was used in vitro on Escherichia coli PQ37 to evaluate the mutagenic effect of the plant extracts. The DPPH method was used to evaluate the antioxidant activity of each plant. The antiproliferative activity was evaluated by MTS method on normal cells (Vero and MCR5) and cancer cells (KB) in contact with the extracts for 72?h. The results showed that the studied plants are not genotoxic. Lantana ukambensis and Acacia macrostachya induced a very significant antiproliferative effect against cancer cells with 94% and 95%, respectively. They also developed a strong antioxidant activity. The IC?? values were 5.96?±?0.40?μg?mL?1 for L. ukambensis and 4.30?±?0.26?μg?mL?1 for A. macrostachya. These two plants are therefore potential sources for isolating new antioxidant and anticancer molecules.     

Correlation between biological activity and energies of electronic transitions in benzodiazepines. Negative ion mass spectrometry and ultraviolet absorption spectroscopy study of some derivatives

A correlation between the energies of electronic singlet transitions in benzodiazepines and their biological activity, which was revealed earlier by means of negative ion mass spectrometry with resonance electron capture, has been verified with a UV absorption spectroscopy investigation. Also, it has been noted that the energies of electronic singlet transitions in benzodiazepines are close in value to the ionization energies of atoms Cs, Rb, K, Na, Li and Tl, the cations of which are known to play an important role in nerve cell excitation processes. Copyright 1999 John Wiley & Sons, Ltd.     

Identification and quantification of phenolic compounds from Balanites aegyptiaca (L) Del (Balanitaceae) galls and leaves by HPLC-MS

Balanites aegyptiaca is a tropical plant which is widely used for medicinal purposes in several African countries, including Burkina Faso. Despite its widespread use, little is known about its phenolic content. This study sought to carry out a screening of the polyphenols from the leaves and galls of B. aegyptiaca. A high-performance liquid chromatography-mass spectrometry method was used to investigate the phenolic content in the parts of the plant studied here. The phenolic acid profile showed the presence of gentisic, p-coumaric, caffeic, ferulic and sinapic acids in the crude and hydrolysed extracts. The flavonoids pattern showed hyperoside, isoquercitrin, rutoside and quercitrin in the crude extract of leaves. Myricetol, quercetol and kaempferol were found after acid hydrolysis of the leaves extract. Ferulic acid, isoquercitrin, rutoside and quercitrin were identified as major phenolic compounds in this study.     

Antioxidant, diuretic activities and polyphenol content of Stereospermum kunthianum Cham. (Bignoniaceae)

Stereospermum kunthianum was used for biological and phytochemical investigations. In biological studies, antioxidant activities were investigated with water, methanol and aqueous acetone extracts. Furthermore, the xanthine oxidase inhibitory activity and the diuretic activity of an aqueous acetone extract were evaluated. In the phytochemical investigations, the flavonoids and polyphenols were quantified spectrophotometrically in all extracts followed by high-performance liquid chromatography-mass spectrometry (HPLC-MS) analysis of an aqueous acetone extract. The 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing/antioxidant power (FRAP) and 2,2'-azinobis (3-ethylbenzoline-6-sulphonate (ABTS) methods have shown that the aqueous acetone extract presents the best antioxidant activities. This aqueous acetone extract was further proven to have interesting xanthine oxidase inhibitory activity, but only a weak diuretic activity. This aqueous acetone extract also possessed the highest phenolic and flavonoid contents. HPLC-MS analysis allowed identifying and quantifying, rutin, isoquercitrin, quercetin, hyperoside, quercitrin and luteolin and the glycosides of ferulic, sinapic p-coumaric acids and kaempferol, apigenin in aqueous-acetone extract.     

Cytotoxic kurubasch aldehyde from Trichilia emetica

Kurubasch aldehyde, a sesquiterpenoid with an hydroxylated humulene skeleton, was isolated as free alcohol from Trichilia emetica Vahl. (Meliaceae), belonging to the order Sapindales. Related substances have been previously found in plants as esters of aromatic acids, and these plants were species belonging to the distant order Apiales. This is the first report of humulenes found in the genus Trichilia and only the second of humulenes in the order Sapindales. The aldehyde is a modest inhibitor of the growth of Plasmodium falciparum (IC50 76 microM) and slow-proliferating breast cancer cells MCF7 (78 microM), but a potent inhibitor of proliferation of S180 cancer cells (IC50 7.4 microM).