New method of producing a more efficient coagulant for the treatment of water from seeds of moringa oleifera.

The coagulation is essential in raw water treatment. The most used coagulants are often of chemical origin and expensive and their use generates non-biodegradable residues. This is why innovative studies on the synthesis of natural coagulants based on plant extracts are very important. This study presents a new method of producing a coagulant for the treatment of water from seeds of moringa oleifera. The application of the new method is done in several steps: Harvesting moringa oleifera seeds, shelling, crushing the seeds, extracting oil from moringa oleifera powder, extracting salts from powder from moringa seeds oleifera, microfiltration with a 0.2 µm filter and lyophilization which gives the final product in dry form. We used the resulting product for coagulation of lake water with an initial turbidity of 40 NTU. This treatment reduced the turbidity of the water by almost 95 % when we used 0.7 mg of this coagulant per liter of water. Moringa has previously been used to produce coagulant but the peculiarity of this study is that it takes a very small amount of the synthesized product to effectively treat water. -The results of this research work have shown that the coagulant produced rom the seeds of Moringa oleifera can be used effectively for the treatment of surface water.-The residual turbidity obtained after the treatment of lake water with the coagulant produced was in accordance with the drinking water standard according to the World Health Organization (WHO) (less than 5 NTU).-The coagulant produced by this new method from moringa oleifera seed is an alternative to aluminum sulfate coagulant for water treatment.

UPLC-QToF-ESI-MS identification and anthelmintic activity of Mitragyna inermis (Willd.) Kuntze (Rubiaceae).

Medicinal plants attract the attention of many researchers to find natural and safe remedies for various resistant diseases. Leaves of Mitragyna inermis are widely used in traditional veterinary medicine for the treatment of gastrointestinal strongyles of small ruminants. The aim of the current study is to estimate the antioxidant, anthelmintic and the larval toxicity of the aqueous and hydroethanolic extracts of this plant in addition to the hexane, dichloromethane and ethanol fractions of the hydroethanolic extract. Investigation of the most active extract using Ultra Performance Liquid Chromatography coupled with Quadrupole Time-of-Flight Electrospray Ionization Mass Spectrometry (UPLC-QToF-ESI-MS). Both plant extracts showed good antioxidant activity by scavenging the 2,2'-diphényl-1-picrylhydrazyl (DPPH) radical and reducing the ferric ion. Similarly, they were no-toxic to Artemia salina larvae (CL50 > 0.1 µg/mL). Also, they significantly reduced larval migration and motility of Haemonchus contortus adult worms (p < 0.001). The hexane, dichloromethane and ethanolic fractions of the hydroethanolic extract showed low activity compared to crude extracts except for the hexane fraction on H. contortus adult worms (p < 0.001) while it showed a poor result on larvae. It thus appears that the anthelmintic activity of the extract may be linked to the synergistic action of these compounds. The UPLC-QToF-ESI-MS analysis revealed the tentative identification of 15 compounds including 7 alkaloids. The results of the present study confirm the anthelmintic activity of M. inermis in traditional veterinary medicine.

Anthelmintic flavonoids and other compounds from Combretum glutinosum Perr. ex DC (Combretaceae) leaves.

A chemical study of the hydro-ethanol extract of the leaves of Combretum glutinosum resulted in the isolation of nine compounds, including 5-demethylsinensetin (1), umuhengerin (2), (20S,24R)-ocotillone (3), lupeol (4), ß-sitosterol (5), oleanolic acid (6), betulinic acid (7), corymbosin (8) and ß-sitosterol glucoside (9). Four compounds have been isolated for the first time from the genus Combretum [viz. (1), (2), (3) and (8)]. The crystal structures of flavonoid (2), C20H20O8, Z' = 2, and triterpene (3), C30H50O3, Z' = 1, have been determined for the first time; the latter confirmed the absolute configuration of native (20S,24R)-ocotillone previously derived from the crystal structures of related derivatives. The molecules of (3) are linked into supramolecular chains by intermolecular O-H...O hydrogen bonds. The crude extracts obtained by aqueous decoction and hydro-ethanolic maceration, as well as the nine isolated compounds, were tested for their anthelmintic activity on the larvae and adult worms of Haemonchus contortus, a hematophage that causes parasitic disorders in small ruminants. The evaluated anthelmintic activity showed that the extracts at different doses, as well as all the compounds tested at 150 µg ml-1, inhibited the migration of the larvae and the motility of the adult worms of the parasite compared with the phosphate buffer solution negative reference control. The best activity was obtained with flavonoids (1), (2) and (8) on both stages of the parasite. The flavones that showed good activity can be used for the further development of other derivatives, which could increase the anthelmintic efficacy.

Antimicrobial Activity and Chemical Composition of "Kpètè-Kpètè": A Starter of Benin Traditional Beer Tchoukoutou.

The aim of this study was to investigate the antibacterial effect of the crude starter "kpètè-kpètè" and lactic acid bacteria used during the production of "tchoukoutou." To achieve this, a total of 11 lactic acid bacteria and 40 starter samples were collected from four communes. The samples were tested on 29 gram + and - strains by disk diffusion method. The minimum inhibitory and bactericidal concentrations of starter and lactic acid bacteria were determined by conventional methods. Organic acids, sugar, and volatile compounds were determined using the HPLC method. The "kpètè-kpètè" displays a high antibacterial activity against the tested strains. The most sensitive strain was S. epidermidis (12.5 mm) whereas the resistance strain was Proteus mirabilis (8 mm). All the tested ferment has not any inhibitory effect on Enterococcus faecalis. The lactic acid bacteria isolates of Parakou showed the highest (17.48 mm) antibacterial activity whereas the smallest diameter was obtained with the ferment collected from Boukoumbé (9.80 mm). The starters' chemical screening revealed the presence of tannins, anthocyanin flavonoids, triterpenes, steroids, reducing compounds, and mucilage O-glycosides. These compounds are probably the source of recorded inhibition effect. The lactic acid bacteria of the "kpètè-kpètè" could be used to develop a food ingredient with probiotic property.

Beninese Medicinal Plants as a Source of Antimycobacterial Agents: Bioguided Fractionation and In Vitro Activity of Alkaloids Isolated from Holarrhena floribunda Used in Traditional Treatment of Buruli Ulcer.

Buruli ulcer (BU) imposes a serious economic burden on affected households and on health systems that are involved in diagnosing the disease and treating patients. Research is needed to find cost-effective therapies for this costly disease. Plants have always been an important source of new pharmacologically active molecules. Consequently we decided to undertake the study of plants used in traditional treatment of BU in Benin and investigate their antimycobacterial activity as well as their chemical composition. Extracts from forty-four (44) plant species were selected on account of reported traditional uses for the treatment of BU in Benin and were assayed for antimycobacterial activities. Crude hydroethanolic extract from aerial parts of Holarrhena floribunda (G. Don) T. Durand and Schinz was found to have significant antimycobacterial activity against M. ulcerans (MIC = 125 µg/mL). We describe here the identification of four steroidal alkaloids from Mycobacterium ulcerans growth-inhibiting fractions of the alkaloidal extract of the aerial parts of Holarrhena floribunda. Holadysamine was purified in sufficient amount to allow the determination of its MCI (=50 µg/mL). These results give some support to the use of this plant in traditional medicine.

Phytochemical Analysis and Biological Activities of Cola nitida Bark.

Kola nut is chewed in many West African cultures and is used ceremonially. The aim of this study is to investigate some biological effects of Cola nitida's bark after phytochemical screening. The bark was collected, dried, and then powdered for the phytochemical screening and extractions. Ethanol and ethyl acetate extracts of C. nitida were used in this study. The antibacterial activity was tested on ten reference strains and 28 meat isolated Staphylococcus strains by disc diffusion method. The antifungal activity of three fungal strains was determined on the Potato-Dextrose Agar medium mixed with the appropriate extract. The antioxidant activity was determined by DPPH and ABTS methods. Our data revealed the presence of various potent phytochemicals. For the reference and meat isolated strains, the inhibitory diameter zone was from 17.5 ± 0.7 mm (C. albicans) to 9.5 ± 0.7 mm (P. vulgaris). The MIC ranged from 0.312 mg/mL to 5.000 mg/mL and the MBC from 0.625 mg/mL to >20 mg/mL. The highest antifungal activity was observed with F. verticillioides and the lowest one with P. citrinum. The two extracts have an excellent reducing free radical activity. The killing effect of A. salina larvae was perceptible at 1.04 mg/mL. The purified extracts of Cola nitida's bark can be used to hold meat products and also like phytomedicine.

Effects of essential oils from medicinal plants acclimated to Benin on in vitro ruminal fermentation of Andropogon gayanus grass.

BACKGROUND: Plants from West Africa commonly used in both human and veterinary medicine contain various secondary metabolites. However, their potential in mitigating ruminal methane production has not been explored. This study examined the effects of seven essential oils (EOs) from plants acclimated to Benin at four dosages (100, 200, 300 and 400 mg L(-1)), on in vitro rumen microbial fermentation and methane production using Andropogon gayanus grass as a substrate. RESULTS: Compared to control, Laurus nobilis (300-400 mg L(-1) ), Citrus aurantifolia (300-400 mg L(-1)) and Ocimum gratissimum (200-400 mg L(-1)) decreased (P < 0.05) methane production (mL g(-1) DM) by 8.1-11.8%, 11.9-17.8% and 7.9-30.6%, respectively. Relative to the control, reductions in methane (mL g(-1) DM) of 11.4%, 13.5% and 14.2% were only observed at 400 mg L(-1) for Eucalyptus citriodora, Ocimum basilicum and Cymbopogon citratus, respectively. These EOs lowered methane without reducing concentrations of total volatile fatty acids or causing a shift from acetate to propionate production. All EOs (except M. piperita) reduced (P < 0.05) apparent dry matter (DM) disappearance of A. gayanus. CONCLUSIONS: The current study demonstrated that EOs from plants grown in Benin inhibited in vitro methane production mainly through a reduction in apparent DM digestibility.

Anti-hyperglycemic effects of three medicinal plants in diabetic pregnancy: modulation of T cell proliferation.

BACKGROUND: Populations in Africa mostly rely on herbal concoctions for their primarily health care, but so far scientific studies supporting the use of plants in traditional medicine remain poor. The present study was undertaken to evaluate the anti-hyperglycemic effects of Picralima nitida (seeds), Nauclea latifolia (root and stem) and Oxytenanthera abyssinica (leaves) commonly used, in diabetic pregnancy. METHODS: Pregnant wistar rats, rendered diabetic by multiple low injections of streptozotocin, were treated with selected plant extracts based on their antioxidant activities. Vitamin C concentrations, fatty acid compositions and phytochemical analysis of plants extracts were determined. Effect of selected plant extracts on human T cell proliferation was also analysed. RESULTS: All analysed plant extracts exhibited substantial antioxidant activities probably related to their content in polyphenols. Picralima nitida exhibited the highest antioxidant capacity. Ethanolic and butanolic extracts of Picralima nitida, butanolic extract of Nauclea latifolia and ethanolic extract of Oxytenanthera abyssinica significantly decreased hyperglycemia in the diabetic pregnant rats. Butanolic extract of Picralima, also appeared to be the most potent immunosuppressor although all of the analysed extracts exerted an immunosuppressive effect on T cell proliferation probably due to their linolenic acid (C18:3n-3) and/or alkaloids content. Nevertheless, all analysed plants seemed to be good source of saturated and monounsaturated fatty acids. CONCLUSION: By having antioxidant, anti-hyperglycemic and immunosuppressive activities, these plants could be good candidates in the treatment of diabetes and diabetic pregnancy.

Antiparasitic activities of two sesquiterpenic lactones isolated from Acanthospermum hispidum D.C.

ETHNOPHARMACOLOGICAL RELEVANCE: Aerial parts of Acanthospermum hispidum D.C. are often used by traditional healers in Benin for various diseases and especially for malaria. AIM OF THE STUDY: To identify active compounds from extracts of Acanthospermum hispidum D.CV. leaves previously shown to possess antimalarial properties and analyse in vivo activity and toxicity of crude extracts. MATERIALS AND METHODS: Compounds were isolated from aerial part of Acanthospermum hispidum D.C. and structurally elucidated using extensive spectroscopic analysis. Antiplasmodial activity was evaluated in vitro against a chloroquine-sensitive strain of Plasmodium falciparum (3D7) using the measurement of the plasmodial lactate dehydrogenase activity and in vivo against Plasmodium berghei berghei by the 4-day suppressive test. Selectivity of extract and purified compounds on Plasmodium parasites were evaluated by using MTT test on J774 macrophage like murine cells and WI38 human normal fibroblasts and also against two other parasites: Trypanosoma brucei brucei and Leishmania mexicana mexicana. Acute and sub-acute toxicities of a crude extract were evaluated on mice. RESULTS: Two known sesquiterpenic lactones were isolated: 1 (15-acetoxy-8ß-[(2-methylbutyryloxy)]-14-oxo-4,5-cis-acanthospermolide) and 2 (9α-acetoxy-15-hydroxy-8ß-(2-methylbutyryloxy)-14-oxo-4,5-trans-acanthospermolide). 1 and 2 showed in vitro antiplasmodial activity against the chloroquine-sensitive strain (3D7) with IC(50) of 2.9±0.5 and 2.23±0.09µM respectively. Only 2 showed a high selectivity index (SI: 18.4) on Plasmodium compared to cytotoxicity against human fibroblasts cell line (WI38). 1 and 2 also showed interesting antiparasitic activities in vitro against Trypanosoma brucei brucei (IC(50) of 2.45±0.49 and 6.36±1.42µM respectively) and Leishmania mexicana mexicana (IC(50) of 0.94±0.05 and 2.54±0.19µM respectively). Furthermore, crude acidic water extract and fractions containing one of the two isolated compounds displayed a weak in vivo antimalarial activity against Plasmodium berghei berghei with a long half-life causing a delayed effect. In vivo acute (2000mg/kg) and sub-acute (1000mg/kg) toxicity tests on the crude acidic water extract did not show toxicity. CONCLUSION: Crude acidic water extract, fractions and pure isolated compounds from Acanthospermum hispidum showed promising in vitro antiplasmodial activity. Despite our study did not show in vivo acute and subacute toxicities of the crude acidic water extract, its weak in vivo antimalarial activity and the in vitro cytotoxicity of pure compounds and enriched extracts containing 1 and 2 indicate that the aerial parts of Acanthospermum hispidum should be used with caution for malaria treatments.

Spasmolytic effects of aqueous extract of mixture from Aframomumum melegueta (K Schum) - Citrus aurantifolia (Christm and Panzer) on isolated trachea from rat.

The spasmolytic properties of the aqueous extract of Aframomum melegueta (K Schum) and Citrus aurantifolia (Christm and Panzer) (AMCA) mixture were tested on isolated rat trachea. Inhibition of the contraction was observed the in presence of the AMCA (EC 50 = 1.80 ± 0.48 mg/mL) after a pre contraction of the trachea by acetylcholine (10⁻5 M). With propranolol (10⁻6 M), the spasmolytic activity of the mixture was inhibited and the concentration-response curve shifted to the right. The EC50 value was then 2.60 ± 0.41 mg/mL. AMCA also inhibited contraction induced by KCl (4.10⁻² M) with EC50 value = 1.86 ± 0.65 mg/mL. These results clearly show the relaxing effect of the aqueous extract on the isolated rat trachea. This effect involved some ß-adrenergic receptor inhibition.

Changes in scopoletin concentration in cassava chips from four varieties during storage.

BACKGROUND: The use of the root crop cassava (Manihot esculenta Crantz) is constrained by its rapid deterioration after harvesting. Chemical and spectroscopic examination earlier revealed the accumulation of the four hydroxycoumarins esculetin, esculin, scopolin and scopoletin derived from the phenylpropanoid pathway, during the time course of postharvest deterioration. In this investigation the scopoletin level in parenchymal samples of four cassava cultivars used in Benin, i.e. Kpaki kpika, Kpaki soan, Logoguesse kotorou and BEN 86052, was investigated by high-performance liquid chromatography (HPLC). RESULTS: Presence was shown in all four varieties with a mean in fresh roots between 4.1 and 11.1 mg kg(-1) dry weight. A strong increase in the content of scopoletin was noticed after a peeling and drying process (6 days) for chip production, the mean content reaching 242.5 mg kg(-1) dry weight in the cultivar BEN 86052. After 3 months of storage this had decreased to 0.7 mg kg(-1) dry weight. CONCLUSION: Strong accumulation of scopoletin in cassava roots used for chip production in Benin is followed by a decrease in its concentration.

Buruli ulcer: a review of in vitro tests to screen natural products for activity against Mycobacterium ulcerans.

Buruli ulcer (BU), caused by Mycobacterium ulcerans, has recently been recognized by the World Health Organization (WHO) as an important emerging disease. It is largely a problem of the poor in remote rural areas and has emerged as an important cause of human suffering. While antimycobacterial therapy is often effective for the earliest nodular or ulcerative lesions, for advanced ulcerated lesions, surgery is sometimes necessary. Antimycobacterial drugs may also prevent relapses or disseminated infections. Efficient alternatives different from surgery are presently explored because this treatment deals with huge restrictive factors such as the necessity of prolonged hospitalization, its high cost, and the scars after surgery. Traditional treatment remains the first option for poor populations of remote areas who may have problems of accessibility to synthetic products because of their high cost. The search for efficient natural products active on M. ulcerans should then be encouraged because they are part of the natural heritage of these populations; they are affordable financially and can be used at the earliest stage. This review provides a number of tests that will help to evaluate the antimycobacterial activity of natural products against M. ulcerans, which are adapted to its slow growing rate, and lists active extracts published up to now in Medline.

Procyanidin-rich fractions from Parkia biglobosa (Mimosaceae) leaves cause redox-sensitive endothelium-dependent relaxation involving NO and EDHF in porcine coronary artery.

AIM OF THE STUDY: Parkia biglobosa leaves are traditionally used as an antihypertensive agent in Benin. The present study assessed the vasorelaxant activity of different Parkia biglobosa leaf extracts using isolated porcine coronary artery rings. MATERIALS AND METHODS: A hydroalcoholic leaf extract was submitted to a multi-step liquid-liquid fractionation with solvents of increasing polarity and the polyphenolic content of the different fractions was analyzed. Vascular reactivity of the different extracts was assessed using porcine coronary artery rings, in the presence or absence of specific pharmacological inhibitors. RESULTS: The hydroalcoholic, ethyl acetate and butanolic extracts contained mainly procyanidins and monomeric flavonoids. Parkia biglobosa leaf crude extract induced a redox-sensitive endothelium-dependent relaxation mediated by both nitric oxide (NO) and endothelium-derived hyperpolarizing factor (EDHF). The fractionation of the butanolic extract generated 6 fractions, two of which induced stronger vasorelaxation than the original extract and they had a higher phenolic content. CONCLUSIONS: Parkia biglobosa leaf extract is able to induce endothelium-dependent NO- and EDHF-mediated relaxation in porcine coronary artery rings. The vasorelaxant activity is dependent on their phenolic content and appears to involve mainly procyanidins.

Validation of a method for the determination of sterols and triterpenes in the aerial part of Justicia anselliana (Nees) T. Anders by capillary gas chromatography.

An accurate and sensitive method, combining soxhlet extraction, solid phase-extraction and capillary gas chromatography is described for the quantitative determination of one triterpene (lupeol) and three sterols (stigmasterol, campesterol and beta-sitosterol) and the detection of another triterpene (alpha-amyrin) from the aerial part of Justicia anselliana. This is the first method allowing the quantification of sterols and triterpenes in this plant. It has been fully validated in order to be able to compare the sterol and triterpene composition of different samples of J. anselliana and therefore help to explain the allelopathic activity due to these compounds. This method showed that the aerial part of J. anselliana contained (292+/-2)mg/kg of lupeol, (206+/-1)mg/kg of stigmasterol, (266+/-2)mg/kg of campesterol and (184+/-9)mg/kg of beta-sitosterol.

Effect of essential oils on the growth of Fusarium verticillioides and fumonisin contamination in corn.

Essential oils extracted by hydrodistillation from local plants in Benin, western Africa, and oil from seeds of the neem tree (Azadirachta indica) were evaluated in vitro and in vivo for their efficacy against Fusarium verticillioides infection and fumonisin contamination. Fumonisin in corn was quantified using a fluorometer and the Vicam method. Oils from Cymbopogon citratus, Ocimum basilicum, and Ocimum gratissimum were the most effective in vitro, completely inhibiting the growth of F. verticillioides at lower concentrations over 21 days of incubation. These oils reduced the incidence of F. verticillioides in corn and totally inhibited fungal growth at concentrations of 8, 6.4, and 4.8 microL/g, respectively, over 21 days. At the concentration of 4.8 microL/g, these oils did not affect significantly fumonisin production. However, a marked reduction of fumonisin level was observed in corn stored in closed conditions. The oils adversely affected kernel germination at 4.8 microL/g and therefore cannot be recommended for controlling F. verticillioides on stored corn used as seeds, when used at this concentration. The oil of neem seeds showed no inhibitory effect but rather accelerated the growth of F. verticillioides.

Evaluation of ethnobotanically selected Benin medicinal plants for their in vitro antiplasmodial activity.

Twenty extracts from nine Benin medicinal plants, traditionally used to treat malaria, were screened for in vitro antiplasmodial activity towards Plasmodium falciparum K1 chloroquine resistant and 3D7 chloroquine sensitive strains. All plants showed antiplasmodial activity below 10 microg/ml. Nine extracts exhibited IC50 values below 5 microg/ml towards one or both of the two strains. The most active extract towards the sensitive 3D7 strain was the methanolic extract of Croton lobatus aerial part, with an IC50 value of 0.38 microg/ml. The best inhibition of the growth of Plasmodium falciparum resistant K1 strain was observed with the methylene chloride extract of Hybanthus enneaspermus and with the methanolic extract of Croton lobatus roots (IC50=2.57 and 2.80 microg/ml, respectively).