Antioxidant and Anti-Inflammatory Activities of Fractions from Bidens engleri O.E. Schulz (Asteraceae) and Boerhavia erecta L. (Nyctaginaceae).

Background: According to recent studies, reactive oxygen is the leader of human metabolic disease development. The use of natural antioxidants is the best way to stop or prevent this problem. Therefore, the aim of this study was to evaluate the antioxidant and anti-inflammatory activities and to determine the polyphenolic contents of the Bidens engleri and Boerhavia erecta fractions. Methods: Plant fractions were obtained using Soxhlet procedures with hexane, dichloromethane, acetonitrile, ethyl acetate, methanol, and butanol solvent, successively. The different fractions were compared according to their antioxidant, anti-inflammatory activities, total phenolic, and total flavonoid contents. The phenolic contribution to the biological activity was evaluated. Result: The Bidens engleri and Boerhavia erecta fractions showed the highest antioxidant abilities, notably the polar fractions, which inhibited significantly the radical 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2-O-azinobis(3-ethylbenzoline-6-sulphonate) (ABTS). The butanol fraction from Bidens engleri and methanol fraction from Boerhavia erecta have presented the best iron (III) reduction power with 211.68 and 198.55 mgAAE/g, respectively. Butanol and acetonitrile were the best solvents for extracting phenolic compounds from Bidens engleri and Boerhavia erecta, respectively. In contrast, dichloromethane was the best solvent for extracting a flavonoid from two plants with anti-COX-2 and anti-LOX-15 active compounds. The phenolic compound contributed significantly to antioxidant activity (r > 0.80). Conclusion: The Bidens engleri and Boerhavia erecta fractions possessed a potential antioxidant for fighting oxidative stress and helping to prevent diabetes, hypertension, and cardiovascular diseases. The uses of this plant could be promoted in Burkina Faso.

Study of antisickling and vasorelaxant activities and acute toxicity assessment of crude extracts of leaves of Ficus sycomorus L. (Moraceae).

The leaves of Ficus sycomorus are used in Burkina Faso folk medicine for the treatment of sickle cell disease. The present comparative study of crude extracts of leaves (decoction, macerated extract and a 95% ethanol extract) was performed with the aim to assess the efficiency of this traditional use and to determine the most active of the three extracts. Antisickling activity was assessed by the Emmel's test. Vasorelaxant effect on rat aortic rings precontracted by phenylephrine with and without N-nitro-L-arginine methyl ester chloride (L-NAME) was also evaluated. The 95% ethanol extract (20 mg mL(-1)) showed the most antisickling activity on sickle erythrocytes, by inhibiting completely sickling of double heterozygote SC cells in 60 min and that of homozygote SS cells in 90 min. On the aorta this extract exhibited a significant (p<0.05) vasorelaxant activity, better than that of the other extracts, with an IC50 value of 6.86±0.13 mg mL(-1) against 18.78±0.38 and 28.56±1.27 mg mL(-1), respectively for the macerated extract and the decoction. When the aortic rings were pretreated with L-NAME, only the ethanolic extract conserved its vasorelaxant activity, up to 73% of relaxation. The acute toxicity of the decoction, assessed by intraperitoneal route and using the Litchfield and Wilcoxon method, led to an LD50 value of 1553.61 mg kg(-1) b.wt. This places the drug among those with low toxicity according to the WHO scale. These results confirm those previously obtained and provide a scientific basis supporting the use of this plant in folk medicine against sickle cell disease. They indicate the importance of Ficus sycomorus in the research of new antisickling molecules.

Antimicrobial activity of polyphenol-rich fractions from Sida alba L. (Malvaceae) against co-trimoxazol-resistant bacteria strains.

BACKGROUND: The increased resistance of microorganisms to the currently used antimicrobials has lead to the evaluation of other agents that might have antimicrobial activity. Medicinal plants are sources of phytochemicals which are able to initiate different biological activities including antimicrobials MATERIALS AND METHODS: In vitro antibacterial (MIC, MBC and time-kill studies) of polyphenol-rich fractions from Sida alba L. (Malvaceae) was assessed using ten bacteria strains (Gram-negative and Gram-positive). RESULTS: All test bacteria were susceptible to the polyphenol-rich fractions. Time-kill results showed that after 5 h exposition there was no viable microorganism in the initial inoculum and the effect of polyphenol-rich fractions was faster on Enterococcus faecalis (Gram-positive bacterium) comparatively to the other bacteria strains. CONCLUSION: The data analysis indicates that the tested of polyphenol-rich fractions has significant effects when compared with the standard antibiotic. These results therefore justify the traditional use of sida alba L., alone or in combination with other herbs to treat bacterial infections.

Evaluation of enzymes inhibition activities of medicinal plant from Burkina Faso.

The aim of the present study was to evaluate some enzymes inhibitory effects of 11 plant species belonging to 9 families from Burkina Faso. Methanolic extracts were used for their Glutathione-s-transferase (GST), Acetylcholinesterase (AChE), Carboxylesterase (CES) and Xanthine Oxidase (XO) inhibitory activities at final concentration of 100 microg mL(-1). The total phenolics, flavonoids and tannins were also determined spectrophotometrically using Folin-Ciocalteu, AlCl3 and ammonium citrate iron reagents, respectively. Among the 11 species tested, the best inhibitory percentages were found with Euphorbia hirta, Sclerocarya birrea and Scoparia dulcis (inhibition > 40%) followed by Annona senegalensis, Annona squamosa, Polygala arenaria and Ceratotheca sesamoides (inhibition > 25%). The best total phenolic and tannin contents were found with S. birrea with 56.10 mg GAE/100 mg extract and 47.75 mg TAE/100 mg extract, respectively. E hirta presented the higher total flavonoids (9.96 mg QE/100 mg extract). It's was found that Sclerocarya birrea has inhibited all enzymes at more than 30% and this activity is correlated to total tannins contents. Contrary to S. birrea, the enzymatic activities of E. hirta and S. dulcis are correlated to total flavonoids contents. Present findings suggest that the methanolic extracts of those plant species are potential inhibitors of GST, AChE, CES and XO and confirm their traditional uses in the treatment of mental disorders, gout, painful inflammations and cardiovascular diseases.

Major enzymatic factors involved in bacterial penicillin resistance in Burkina Faso.

Many clinical species of bacteria were isolated from biological samples such as urines, blood and wound in Saint Camille medical centre of Ouagadougou. Among the concerned species, the most important members were Escherichia coli and Klebsiella pneumoniae. These p-lactamases producing isolates were directly screened by PCR to identify the nature of the amplified genes responsible for penicillin destroying activity. Therefore specific TEM and SHV primers were used. The PCR products were sequenced. The sequencing results indicated that the parental forms bla(TEM-1) and bla(SHV-1) were the most common determinants of beta-lactamase found, respectively in Escherichia species and Klebsiella pneumoniae. The bacterial susceptibility analysis by MICs measurement clearly correlated the presence of concerned beta-lactamase determinants and their resistance patterns. This study is part of a set of investigations carried out by our laboratory to assess the beta-lactamase incidence in the failure of beta-lactam therapy. In particular, the purpose of this study was to determine the precise nature of beta-lactamase supporting the low susceptibility of host bacteria towards penicillins.

Therapeutic uses of honey and honeybee larvae in central Burkina Faso.

The therapeutic uses of hive-derived products by local people in four zones from the central part of Burkina Faso are described. Of 13 apitherapeutic applications recorded, only honey (12) and honeybee larvae (1) were used. The uses described included treatment of various gastrointestinal disorders, respiratory ailments, fatigue, vertigo, ophthalmic disorders, toothache, measles, wounds, burns, chest pains, period pains and postnatal disorders, male impotence as well as its application as a skin cleansing agent. The effectiveness against some of these conditions, e.g. measles, period pains and postnatal disorders, requires further investigation and confirmation.