Antioxidant and antibacterial activities of Piliostigma reticulatum (DC.) Hochst extracts

The methanol and aqueous extracts of Piliostigma reticulatum barks were investigated for its antioxidant and antibacterial activities. The antioxidant test using 1,1-diphenyl-2-picrylhydrazyl (DPPH) method demonstrated important radical scavenging activity for the methanol extract with IC50 = 0,37 ± 0,04 μgmL-1. The 2 extracts were then examined for antibacterial activity by using the broth micro dilution method. The extracts possessed the antibacterial effect against the almost germs tested; the aqueous extract exhibited a better activity than methanol extract. These results indicate that methanol and aqueous extracts of P. reticulatum could be used as a source of antioxidant and antibacterial ingredients in the food industry.Keywords: Piliostigma reticulatum, Ceasalpiniaceae, bark extracts, antioxidant, antibacterialAfrican Journal of Biotechnology Vol. 9(33), pp. 5407-5411, 16 August, 201

ENDOTHELIUM-INDEPENDENT AND ENDOTHELIUM-DEPENDENT VASORELAXATION BY A DICHLOROMETHANE FRACTION FROM ANOGEISSUS LEIOCARPUS (DC) GUILL. ET PERR. (COMBRETACEAE): POSSIBLE INVOLVEMENT OF CYCLIC NUCLEOTIDE PHOSPHODIESTERASE INHIBITION.

Many traditional medicinal herbs from Burkina Faso are used to treat arterial hypertension (HTA). Among them, Anogeissus leiocarpus (A. Leiocarpus) which is well known and widely used in Burkina traditional medicine. Herein we assess the effects of dichloromethane fraction from A. leiocarpus stem bark (ALF), selected as the most active on cyclic nucleotide phosphodiesterases (PDEs) and characterized its specificity towards purified vascular PDE1 to PDE5 isoenzymes and study its effects on a vascular model. ALF potently and preferentially inhibits (IC50=1.6 ± 0.6 µg/mL) the calmodulin-dependent phosphodiesterase PDE1, being mainly present in vascular smooth muscle and preferentially hydrolyses cGMP. In the same range (IC50 =2.8 ±0.2 µg/ml) ALF inhibits PDE2, a cGMP-activated enzyme that is only present in endothelial cells and hydrolyses both cAMP and cGMP. PDE5, which specifically hydrolyses cGMP and which mainly contributes to cGMP hydrolysis is also potently inhibited by ALF (IC50=7.6±3.5 µg/ml). The potencies of ALF on cAMP hydrolyzing isoenzymes was lesser, being more effective on PDE4 (IC50= 17.6±3.5 µg/ml) than on PDE3 (60.9 ± 1.8 µg/ml). Since the major effect of ALF were against cGMP hydrolysis and since cGMP is implicated in endothelium-dependent relaxation, the endothelium-dependent vasorelaxation was studied on isolated porcine coronary arteries rings pre-contracted with U46619. The endothelium-dependent vasorelaxation is significantly inhibited by Nω-nitro-L-arginine (LNA 300 µmol/L, an inhibitor of endothelial NO synthase), but not affected by charybdotoxin (CTX, 100nM) plus apamin (APA, 100nM) (two inhibitors of EDHF-mediated responses). The combination of 4-aminopyridine (4-AP, 1 mmol/L, inhibitor of voltage-dependent potassium channels, Kv) plus baryum (Ba2+, 30 µmol/L, inhibitor of the potassium channels with entering correction, Kir) plus ouabain (3 µmol/L, inhibitor of ATPase Na+/K+ channels) partially inhibits endothelium-independent vasorelaxant effect. This endothelium-independent relaxant effect was also sensitive to combination of 1H-[1,2,4]-oxadiazole-[4,3-α]-quinoxalin-1-one (ODQ, 10 µM, soluble guanylyl cyclase inhibitor) and N-[2-(p-Bromocinnamylamino)ethyl]-5-isoquinoline sulfonamide dihydrochloride (H89, 100 nM, Protein Kinase A inhibitor). Taken together, these results indicate that ALF is a powerful vasodilator modulated by the formation of NO from endothelium, but also act by directly relaxing the vascular smooth muscle cells, by inhibiting cGMP hydrolyzing PDEs (PDE1, PDE2 and PDE5) and to a lesser extend on cAMP degradation (PDE3 and PDE4), cAMP and cGMP being second messengers involved in vascular relaxation

Pharmacological study of trunk bark of Acacia nilotica var adansonii (Guill et Perr).o Ktze (Mimosaceae): Assays, antioxidant and antispasmodic activities

Aim of this study was to evaluate in vitro polyphenols content, antioxidant and antispasmodic properties of the aqueous extract and fractions of the trunk bark of Acacia nilotica. According to a survey conducted in rural Burkina Faso, Acacia nilotica var. adansonii (Guill and Perr). Ktze reported to be widely used in the treatment of gastrointestinal diarrhoea and parasitosis. A maceration of the powder of the trunk bark of the plant was carried out. Then the aqueous macerate obtain, was fractionated with dichloromethane, butanol and ethyl acetate successively. The phenolic compounds of the aqueous extract, butanol and ethyl acetate fractions was determinated. The antioxidant activity of aqueous extract and fractions was evaluated by the DPPH, ABTS and FRAP tests. The contractility test on smooth muscle was realized according to Magnus method. Assay of the extracts revealed a high content of polyphenols, tannins and flavonoids. The aqueous extract, the butanol fraction and the ethyl acetate fraction demonstrated a high antioxidant capacity. Aqueous extract showed a better antispasmodic effect of acetylcholine contraction induction at 1 μM (IC50 = 13.02 μg / mL) and for BaCl2 at 160 μg / mL (IC50 = 117.2 μg / mL). The aqueous extract of Acacia nilotica and his fractions had antioxidant properties. Only aqueous extract proven better antispasmodic property. Hence its use in traditional medicine in the treatment of diarrhoea. Keywords: Acacia nilotica, Antioxidant, Antispasmodi

Preliminary clinical assessment of a gentamicin-loaded monoolein gel intended to treat chronic osteomyelitis

The aim of this study was to perform a preliminary clinical assessment of efficacy and safety of a biodegradable gentamicin-loaded monoolein gel. An open single dose, one treatment study including 19 patients with chronic osteomyelitis caused by a microorganism sensitive to gentamicin was conducted. After surgical curettage of the infected bone, the dead space was filled in with the gentamicin-loaded monoolein gel. To prevent post-operative septicaemia, a systemic antibiotherapy was prescribed for 3 days following the operation. Clinical,biological and radiological follow-up was performed to assess the efficacy and the safety of the treatment. After a follow-up period ranging from 2 to 12 months, all 19 patients included in the study felt well. Eighteen patients recovered from chronic osteomyelitis without adverse events. The wound of one patient whose bone was exposed did not scar over after 10 months. However, it was no longer infected In conclusion, gentamicin-loaded monoolein gel was efficacious in treating chronic osteomyelitis without side-effects. © 2008 Academic Journals Inc.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

An overview of cancer chemopreventive potential and safety of proanthocyanidins

Cancer is a major public health problem worldwide. Over two-thirds of cancer-related deaths could most probably be prevented through lifestyle modification, particularly through dietary means. Proanthocyanidins (PAs), the most abundant polyphenolic substances after lignin in the plant kingdom, have been widely investigated for their chemopreventive potential. The PAs literature has, however, been mostly concerned with positive cardiovascular activities, and recent reviews about cancer chemoprevention are scarce. The present review highlights a series of in vitro and in vivo studies indicating (1) that PAs can act as anticarcinogenic agents through their antioxidant, apoptosis-inducing, immuno-modulating, and/or enzyme modulating properties, effects on epigenetics; and (2) that PAs could be particularly safe dietary compounds. These convergent data encourage further research to better understand the many aspects of cancer chemoprevention by PAs. © 2011 Copyright Taylor and Francis Group, LLC.http://dx.doi.org/10.1080/01635581.2011.607549SCOPUS: re.jinfo:eu-repo/semantics/publishe