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Aim: Dissotis rotundifolia were selected after an ethnopharmacological survey conducted on plants used traditionally for malaria treatment in South Benin, with the aim of discovering new natural active extracts against malaria parasites. Place and Duration of Study: Laboratory of Biochemistry and Bioactive Natural Substances, University of Abomey-Calavi (Benin)/ Laboratory of Infectious Vector Borne Diseases, Regional Institute of Public Health (Benin)/ Laboratoire d’Histologie, de Cytogénétique et d’Embryologie, Faculté des Sciences de la Santé (Benin). The study was conduct from October 2018 to June 2019 in Benin. Methodology: The antiplasmodial activity of the plant extracts was evaluated using the parasite lactate dehydrogenase (pLDH) immunodetection assay. The extract with the best antiplasmodial activity were used on Wistar rats for acute toxicity. Results: Ethanolic extract of Dissotis rotundifolia showed promising activity (Isolate: IC50 = 22.58 ± 1.12 µg/mL; 3D7: IC50 = 6.81 ± 0.85 µg/mL) on Plasmodium falciparum compared to the aqueous extract (Isolate: IC50 > 100 µg/mL; 3D7: IC50> 100 µg/mL). The aqueous fraction of D. rotundifolia exhibit highly potent activity against P. falciparum strain (Isolate: IC50 > 100 µg/mL μg/mL; 3D7: IC50 = 4.05 ± 0.72 μg/mL). Haemolytic effect of actives extracts and fractions is less than 5%. Ethanolic extract of D. rotundifolia revealed no obvious acute toxicity in rat up to the highest dose administered (2000 mg/kg). Conclusion: This study justifies traditional uses of D. rotundifolia against malaria. A bioguided fractionation of these extracts would identify molecules responsible for their antiplasmodial activity. Moreover, these results could lead to the design of improved traditional medicines in the basis of this plant.

Dialium guineense (Caesalpiniaceae) and Trema orientalis (Celtidaceae) are traditionally used to treat and manage many diseases such as hypertension, headache and diabetes. Despite their recognized efficacy in traditional medicine, their antihypertensive properties are not yet effective. Therefore, the current study aimed to investigate the antihypertensive effect of ethanolic extracts of Dialium guineense and Trema orientalis on L-NAME-induced hypertensive rats. The systolic, diastolic and mean arterial pressure were recorded using CODA™ non-invasive blood pressure system. The phenolic compounds were also quantified using High Pressure Liquid Chromatography. Ethanolic extracts of both plants induced significant decrease of mean arterial pressure. At 500 mg/kg bw, both plants decreased mean arterial pressure from 126.4 ± 0.48 to 90.6 ± 3.12 mmHg and from 154.8 ± 7.84 to 103 ± 5.6 mmHg respectively for Dialium guineense and Trema orientalis. Losartan and Captopril, used as standard drugs at 100 mg/kg body weight, also significantly decrease blood pressure. Trema orientalis was the most active with a blood pressure reduction percentage of 33.46 ± 3.06 % comparable to Losartan (31.37 ± 3.13 %) and Captopril (31.76 ± 2.63 %). The probable bioctives compound identified were chlorogenic, gallic, caffeic, ellargic, tannic acids, and luteolin, isorhamnetin and chrysin.

Organochlorines pesticides (OCPs) which utilization is banned, affect nutrition quality of vegetables. Recent research shown their presence in different vegetables. Since last study carried out in 2007 about vegetables contamination by OCPs residues in Benin, none research is done about OCPs residues monitoring in vegetables. This study was conducted to monitor OCPs residues in two vegetables (Solanum macrocarpum L. and Lactuca sativa L.) collected from 4 farms sites in two communes (Cotonou and Seme-kpodji) of Benin. A total of 31 samples of Solanum macrocarpum L. and Lactuca sativa L. were collected from the study areas and analyzed for 13 OCPs residues, which can be grouped into DDTs, Aldrins, Endosulfans, HCHs and Methoxychlor. The data revealed that 100% of the vegetable samples were contaminated by OCPs residues. Aldrin, Dieldrin, Endrin, Endosulfan sulfate, pp’-DDE and pp’-DDT concentrations found were below the maximum residue limits (MRLs) set by European Union (EU) whereas 31.25%, 37.5%, 43.75% of β-HCH, -Endosulfan, β-Endosulfan concentrations found in Solanum macrocarpum L. were above the EU MRLs adopted values. In Lactuca sativa L., the levels of β-HCH and β-Endosulfan were about 6.67% each and were above the EU (MRLs). Many of OCPs residues levels are below MRLs while three OCPs residues exceeded EU MLRs. This observation suggests that vegetables contamination is due to the persistence of OCPs residues in the soil where vegetables were cultivated. We therefore propose the monitoring of OCPs and other pesticide residues in vegetables cultivated in Benin to perform nutritional quality of vegetables.

Background In urban settings of Africa with rapidly increasing population, traffic-related air pollution is a major contributor to outdoor air pollution (OAP). Although OAP has been identified as a leading cause of global morbidity and mortality, there is however, lack of a simple biomarker to assess levels of exposure to OAP in resource-poor settings. This study evaluated the role of exhaled carbon monoxide (exhCO) as a potential biomarker of exposure to ambient carbon monoxide (ambCO) from OAP. Methods This was a descriptive study conducted among male commercial motorcycle riders in Cotonou – the economic capital of Benin. The participants’ AmbCO was measured using a portable carbon monoxide (CO) data logger for 8 h during the period of their shift. ExhCO was measured just before and immediately after their shift (8-h) Participants were asked not to cook or to smoke during the day of the measurements. Linear regression analysis was used to assess the association between ambCO and exhCO for the last 2, 4 and 6 h of their shift. Results Of 170 participants who completed the study, their mean ± SD age was 42.2 ± 8.4 years, and their mean ± SD daily income was 7.3 ± 2.7$. Also, 95% of the participants’ used solid fuels for cooking and only 2% had ever smoked. Average exhCO increased by 5.1 ppm at the end of the shift (p = 0.004). Post-shift exhCO was significantly associated to ambCO, this association was strongest for the last 2 h of OAP exposure before exhCO measurement (β = 0.34, p

Increasing consumer awareness regarding the health benefits of different nutrients in food has led to the requirement of assessing the effect of food processing approaches on the quality attributes. The present work focuses on understanding the effects of ultrasound (US) processing, mild heat pasteurization (65°C for 15 min), thermal pasteurization (80°C for 15 min) and their combination on physicochemical, microbiological properties and nutritional quality of pineapple juice through 60 days of storage at room temperature. Ultrasound treatment showed significantly lower browning degree. Ultrasound followed by ultrasound combined with mild heat pasteurization (UMP) treatments was effective in retaining the total phenolic content of pineapple juice as compared to the thermal treatment or the untreated juice sample at room temperature during 60 days of storage. Thermal pasteurization (TP) followed by ultrasound combined with mild heat pasteurization (UMP) and ultrasound (US) treatment, in increasing order, was found to be effective in delaying microbial growth in pineapple juice. This study demonstrates that ultrasound combined with mild heat pasteurization treatments could be able to effectively inactivate the microorganisms and pectin methylesterase in pineapple juice whilst preserving relatively high amount of phenols.

BACKGROUND: Substantial evidence indicates that cytophilic IgG responses to Plasmodium falciparum merozoite antigens play a role in protection from malaria. The specific targets mediating immunity remain unclear. Evaluating antibody responses in infants naturally-exposed to malaria will allow to better understand the establishment of anti-malarial immunity and to contribute to a vaccine development by identifying the most appropriate merozoite candidate antigens.METHODS: The study was based on parasitological and clinical active follow-up of infants from birth to 18 months of age conducted in the Tori Bossito area of southern Benin. For 399 infants, plasma levels of cytophilic IgG antibodies with specificity for five asexual stage malaria vaccine candidate antigens were determined by ELISA in infants' peripheral blood at 6, 9, 12 and 15 months of age. Multivariate mixed logistic model was used to investigate the association between antibody levels and anti-malarial protection in the trimester following the IgG quantification. Moreover, the concentrations of merozoite antigen-specific IgG were compared between a group of infants apparently able to control asymptomatic malaria infection (CAIG) and a group of infants with no control of malaria infection (Control group (NCIG)). Protective effect of antibodies was also assessed after 15 months of malaria exposure with a Cox regression model adjusted on environmental risk.RESULTS: Cytophilic IgG responses to AMA1, MSP1, MSP2-3D7, MSP2-FC27, MSP3 and GLURP R2 were associated with increasing malarial infection risk in univariate analysis. The multivariate mixed model showed that IgG1 and IgG3 to AMA1 were associated with an increased risk of malarial infection. However infants from CAIG (n = 53) had significantly higher AMA1-, MSP2-FC27-, MSP3-specific IgG1 and AMA1-, MSP1-, MSP2-FC27-, MSP3 and GLURP-R2-specific IgG3 than those from NCIG (n = 183). The latter IgG responses were not associated with protection against clinical malaria in the whole cohort when protective effect is assessed after 15 months of malaria exposition.CONCLUSION: In this cohort, merozoite antigen-specific cytophilic IgG levels represent a marker of malaria exposure in infants from 6 to 18 months of age. However, infants with resolution of asymptomatic infection (CAIG) seem to have acquired naturally immunity against P. falciparum. This observation is encouraging in the context of the development of multitarget P. falciparum vaccines.

In Benin, malaria is a major public health concern, especially for children under five years and pregnant women. Considering the inefficiency of the health centers in some regions, people use plants for their primary health care. This study aimed to identify and document the medicinal plants used in the treatment of malaria in four departments (Littoral, Oueme, Plateau and Zou) of south Benin. Data were recorded using interview and field observation. 42 informants including 15 traditional healers and 27 medicinal plants sellers with an average of fourteen years of experience were interviewed. Plants were identified by a botanist from the National Herbarium of Benin. The study revealed that a total of 34 plants species belonging to 33 genera and 24 families were collected. The most frequently cited plant species was Chamaecrista rotundifolia, Senna siamea and Dialium guineense. Caesalpinioideae and Rubiaceae are the most families mentioned by the informants. The most common preparation method is decoction and the route of administration is oral. The results contributed to the conservation of empirical knowledge of medicinal plants used for the treatment of malaria and could help to identify new research topics in connection with the implementation of Traditional Medicines. Key words: Medicinal plants, malaria, traditional knowledge, Benin.

Sweet potato is an important staple food in Benin, which unfortunately remains neglected by research and underutilized. To document the diversity of the crops for its sustainable conservation and use, an ethnobotanical investigation was conducted in 34 villages selected in Central and Southern Benin using participatory research approach methods and tools. For 24.59 % of the respondents, sweet potato is ranked as the sixth most important crop produced. 19.36 % of the respondents produced sweet potato for feeding purpose only, while 46.77 % of respondents are growing it for purely economic purposes. At total 12 constraints related to the sweet potato production were registered through the study area, among which eight, which represent 66.67 % of the constraints could be solve by the scientific research efforts while the rest (four constraints, 33.33 %) were purely of political order. The difficulty of farming practices (20.39 % of responses) and the sensitivity of the crop to the attack of pests and insects (19.74 % of responses) appeared as the major constraints cited by the respondents. The numbers of sweet potato varieties per village range from 2 (two) to 11 (eleven) with an average of 5 varieties per village. The Shannon diversity index of the South (4.06) is greater than the one of the Centre (4.00) and shows that South region has a relatively highest range of varieties and so suitable for the crops diversity conservation. At 65 % of similarity, the cluster analysis using UPGMA dendrogram classified the 108 sweet potato cultivars identified in eight groups corresponding to 92 morphological units based on 13 agronomic traits and culinary characteristic. Within the varietal group, it denotes some yellow (27.45 %) and orange (3.92 %) flesh variety groups of sweet potato which constitute potential source of vitamin A. The study of the vitamin A (caroten) content of those varieties is to be considered to fully exploit their nutritional potential.

Chili peppers play a significant role in the world diet and can contribute to the improvement of horticultural producers’ incomes. In Benin, chili pepper production is hampered by many challenges that need to be characterized, prioritized and addressed. Moreover, the existing diversity, as well as the agronomic potential, of the varieties being cultivated in Benin is still not well understood. In order to define the scientific basis for the improvement of chili pepper production and the preservation of its diversity, one hundred villages were randomly selected and surveyed in Northern and Central Benin by using participatory research appraisal tools and techniques. Twelve production constraints were identified, of which low productivity (19 %), soil infertility (18.5 %), drought (18.3 %), pests and disease susceptibility (17.9 %), early fall of plant organs (15 %) appear as the most important. In terms of diversity, 77 chili pepper varieties (40 from the frutescens group, 24 from the annuum group and 13 from the chinense group) including 72 local and five introduced varieties (Tatache, Yeyekouka, Yeyekouokoure, Cote d’ivoire and MC) were found. The number of varieties varies from three to seven (four on average) per village and from one to five by household. The proportion of loss of diversity per village varies from 0 to 75 % with an average of 26.61 %. Susceptibility to pests and diseases (37.1 % of responses), early fall of plant organs (11.6 % of responses) and susceptibility to drought (8.5 %), were the most important reasons given in attempts to explain the loss of diversity. Farmers’ varietal preference criteria are essentially agronomic (90.4 % of responses). The participative agronomic evaluation revealed that the varieties of frutescens group are significantly higher with respect to the evaluated variables, but they are less appreciated by the consumers.

Cassava (Manihot esculenta Crantz) is one of the highly produced and consumed food crops in Benin Republic. Through the application of participatory research appraisal tools and techniques, such as direct observations, group discussions and field visit, cassava production constraints, the diversity at the community level and farmers’ varieties preference criteria were assessed in southern Benin. Base on national statistic cassava production fifty five (55) villages were selected and surveyed in the southern Benin. Descriptive statistics were used to analyse the data collected. About 11 constraints were listed by farmers, and the most important were low productivity, low post-maturity underground storage capacity of the roots of some cultivars, viral disease (cassava mosaic disease), susceptibility to high soil moisture, and lack of early maturing cultivars, which together accounted for 68.02 % of the total responses. Additionally, a total of 125 existing landraces were recorded. The distribution and extent pattern revealed 59 elites cultivars (cultivated by many households and on large areas) that were further grouped into 23 categories based on their agronomic, technological and culinary characteristics. In most of the villages, the farmers’ perception of cultivar loss was based on abandonment of some cultivars due to their poor agronomic (69.12 % of responses) and culinary and/or technological attributes (30.88 % of responses). Within the existing diversity, cultivar choice or preferences are based on 22 culinary, technological, agronomic and economic criteria and their importance vary across the different department. Among these criteria, the most important were high productivity, good quality of the gari, early maturity and good friability accounted together for 48.12 % of the total responses. The presence of duplicates or synonyms was also observed and it is suggested that both morphological and molecular characterization and classification be carried out for better identification of cultivars.

In the past, cervical cancer has been linked to Human Papilloma Virus (HPV) infection. Previously, we found that pre-neoplastic breast and ovarian lesions may be associated with lamin A/C deficiency, resulting in abnormal nuclear morphologies and chromosomal instability. Ultimately, these phenomena are thought to lead to cancer. Here, we assessed lamin A/C deficiency as an indicator for the risk to develop cervical cancer. The expression of lamin A/C was assessed by Western blotting in cervical uterine smears (CUS) of 76 adult women from Benin concomitant with nuclear morphology assessment and HPV genotyping using microscopy and PCR-based assays, respectively. In vitro analyses were performed to uncover the mechanism underlying lamin A/C expression alterations observed in vivo. The presence of cervical intra-epithelial neoplasia (CIN) was assessed by colposcopy. Normal lamin A/C expression (group A) was observed in 39 % of the CUS, weak lamin A/C expression (group B) was observed in 28 % of the CUS and no lamin A/C expression (group C) was observed in 33 % of the CUS tested. Infection with oncogenic HPV was found to be significantly higher in group C (36 %) than in groups A (17 %) and B (14 %). Two years after our first assessment, CIN was observed in 20 % of the women in group C. The in vitro application of either a histone deacetylase inhibitor (trichostatin) or a protein kinase inhibitor (staurosporine) was found to restore lamin A/C expression in cervical cancer-derived cells. Lamin A/C deficiency may serve as an independent risk factor for CIN development and as an indicator for preventive therapy in cervical cancer.

Resume Objectif Cette etude transversale visait a determiner la prevalence et a caracteriser les genotypes a haut risque du HPV circulant chez les adolescentes a Ouagadougou. Methodologie De septembre a decembre 2013, 200 adolescentes, recrutees dans un centre d’ecoute pour jeunes, ont volontairement accepte un ecouvillonnage du canal endocervical. L’identification des genotypes du Papillomavirus humain (HPV) a ete realisee par la technique de reaction de polymerisation en chaine en temps reel. Resultats La moyenne d’âge des adolescentes etait de 18,7 ± 0,7 ans et 83/200 adolescentes etaient positives a au moins un genotype a haut risque de HPV, soit une prevalence de 41,5 %. Douze genotypes correspondant a 136 infections ont ete caracterises : HPV 52 (22,8 %), HPV 59 (14,0 %), HPV 39 (13,2 %), HPV 35 (10,3 %), HPV 51 (10,3 %), HPV 56 (8,8 %), HPV 16 (5,2 %), HPV 18 (5,2 %), HPV 58 (4,4 %), HPV 31 (3,6 %), HPV 45 (1,5 %), HPV 33 (0,7 %). Une infection multiple (2 a 5 virus), statistiquement associee a l’âge ( p = 0,0318), etait detectee chez 42,2 % des adolescentes infectees. Si le nombre de partenaires sexuels etait statistiquement associe au portage du HPV (OR = 2,18 ; IC a 95 % = 1,17–4,09), la precocite des rapports sexuels et le changement recent de partenaire sexuel ne l’etaient pas ( p > 0,05). Conclusion La prevalence du portage du HPV dans cette etude est elevee, comme decrit chez les jeunes en debut d’activite sexuelle. Les genotypes identifies sont differents de ceux cibles par les vaccins prophylactiques actuellement disponibles. Une plus large etude pour cartographier les genotypes du HPV a haut risque circulant en Afrique de l’Ouest est necessaire pour un vaccin adapte.

Sorghum (Sorghum bicolor (L.) Moench) is an important staple food in semi-arid tropics which contribute to food security and poverty alleviation in Benin. However, its production is seriously facing enormous abiotic and biotic stresses including climate variability. To document its cultivar diversity, the impact of climate change on its production and diversity, the adaptation strategies developed by farmers and the performance of landraces, 22 villages were randomly selected and surveyed in the Department of Atakora in the northwest of Benin using participatory research appraisals (fields and granaries visit, individual and group survey using questionnaires, Four cells or distribution and extent analysis, etc.). Data were analysed through descriptive statistics (frequencies, percentages, means, etc.) to generate summaries and tables at different (villages, individuals) levels and also through multivariate analysis (cluster analysis) and the results figures. In total 8 constraints affecting sorghum production were recorded among which striga proliferation, soil poverty and climate change effects (drought; excess of rain; delay, insufficient and irregular rainfall, etc.) were the most important. Subject to synonyms, 89 sorghum landraces were inventoried and their number varied from 4 to 17 (7 on average) per village. The Shannon–Weaver diversity index (H) estimated at 3.02 indicated high sorghum diversity in the study area. Many landraces were threatened. The relatively high rates (16.7–88.2 %; 40.9 % on average) of cultivars loss recorded per village are proofs of menace of genetic erosion and necessity of developing conservation strategies. Inadaptability of cultivars to climate variability (39.6 % of abandoned landraces) was among others the most important reason justifying the loss of diversity. Crop rotations, growing of early maturing and/or drought tolerant landraces, establishment of fields in lowlands are the most important strategies developed by farmers to mitigate impacts of climate change (low productivity, increase of damages from storage insects, early drying of plant leaves etc.) on the crop. Participatory evaluation of the existing landraces led to the identification of some high-performing ones that are resistant/tolerant to diverse abiotic and biotic stresses. Farmers’ cultivars preference criteria were identified and prioritized. Results of this study are useful to policy makers, agricultural extension services of the different districts, genetic resources specialists and breeders in order to improve sorghum production in Benin.

Kersting’s groundnut (Macrotyloma geocarpum) locally named “Doyi” is a grain legume of high nutritional and economic value widely consumed in Benin but neglected by the scientific research and the development programmes. In order to document the indigenous knowledge related to the production, diversity and use of this crop and to collect samples for characterisation and evaluation, 30 villages from South and Centre of Benin were randomly selected and surveyed. In each village, 10–15 producing households (374 farmers in total) were chosen as above and interviewed using participatory research appraisal tools and techniques. The study revealed that the production of Kersting’s groundnut is particularly concentrated in central Benin (departments of Zou and Collines), but is seriously declining for ten reasons. As reported by farmers, the most important factors of those included the high cost of production (40.7 % of responses), the susceptibility of cultivars to high soil moisture (25.5 % of responses) and the complexity of the cultural practices (25.2 % of responses). Only three local cultivars differing mostly by the colour of seed coat (white, red and black) were recorded. The white seeded cultivar was the most cultivated and preferred for consumption. Gender role analysis indicated that young women were the most involved in the cultivation of M. geocarpum. Phenotypical analysis of the different accessions (32 in total) collected during the study revealed only three groups that differ mainly in leaf width, yield and date to 50 % flowering. Agronomic evaluation indicated a significant difference (p

Guinea yam (Dioscorea cayenensis Lam.–D. rotundata Poir. complex) is an important tuber crop that highly contributes to food security and poverty alleviation in Benin. However, its production is seriously affected by many biotic and abiotic constraints which could be overcame by concentrating the production on resistant or tolerant cultivars. In order to identify such cultivars that are known to exist in Benin traditional agriculture, 51 villages were randomly selected throughout the production zones and surveyed. Out of the 426 cultivars (subject to synonymy) evaluated using participatory approach and 13 agronomic, culinary, and technological traits, 25, 47, 49, 64 and 64 cultivars respectively tolerant to poor soils, nematodes, high soil moisture (adaptability to lowland), drought and chips (peeled and dried tuber) storage insects were, among others, identified. These pools of cultivars could serve in breeding program or be directly used in varietal exchanges towards the zones of interests. The agromorphological characterisation conducted per pool of performing cultivars revealed the existence of many duplicates that should be clarified with the use of molecular markers. Flowering, sex and intensity of flowering of the different cultivars were analysed and revealed a low rate (11.68 %) of non-floriferous plants, a high rate (61.03 %) of plants with low intensity of flowering and five types of male inflorescences indicating a hypothetical evolution towards the suppression of flowering with the cultivated yams.

Sorghum [Sorghum bicolor(L.) Moench] is an important staple food crop in northern Benin. In order to assess its diversity in Benin, 142 accessions of landraces collected from Northern Benin were grown in Central Benin and characterised using 10 qualitative and 14 quantitative agromorphological traits. High variability among both qualitative and quantitative traits was observed. Grain yield (0.72–10.57 tons/ha), panicle weight (15–215.95 g), days to 50% flowering (57–200 days), and plant height (153.27–636.5 cm) were among traits that exhibited broader variability. Correlations between quantitative traits were determined. Grain yield for instance exhibited highly positive association with panicle weight(r=0.901, P=0.000)and 100 seed weight(r=0.247, P=0.000). UPGMA cluster analysis classified the 142 accessions into 89 morphotypes. Based on multivariate analysis, twenty promising sorghum genotypes were selected. Among them, AT41, AT14, and AT29 showed early maturity (57 to 66 days to 50% flowering), high grain yields (4.85 to 7.85 tons/ha), and shorter plant height (153.27 to 180.37 cm). The results obtained will help enhancing sorghum production and diversity and developing new varieties that will be better adapted to the current soil and climate conditions in Benin.

Questionnaire. (DOCX 11Â kb)

International audience; Aflatoxin B1 (AFB1) is a carcinogenic mycotoxin produced by Aspergilli of the section Flavi that may contaminate food, in the field or during storage. Cassava represents an important staple food in sub-Saharan Africa. The analysis of aflatoxigenic fungi in 36 cassava samples obtained from producers in Benin indicated that 40% were contaminated by Aspergilli of the section Flavi. Upon morphological and molecular characterization of the 20 isolates, 16 belonged to Aspergillus flavus, 2 to Aspergillus parvisclerotigenus and 2 to Aspergillus novoparasiticus. This is the first time that this latter species is isolated from food. Although most of these isolates were toxigenic on synthetic media, no AFB1 contamination was observed in these cassava samples. In order to determine the action of cassava on AFB1 synthesis, a highly toxigenic strain of A. flavus, was inoculated onto fresh cassava and despite a rapid development, no AFB1 was produced. The anti-aflatoxin property was observed with cassava from different geographical origins and on other aflatoxigenic strains of the section Flavi, but it was lost after heating, sun drying and freezing. Our data suggest that fresh cassava is safe regarding AFB1 contamination, however, processing may alter its ability to block toxinogenesis leading to secondary contamination. (C) 2013 Elsevier Ltd. All rights reserved.

Casuarina equisetifolia (L.) (Casuarinaceae) and Oxalis corniculata (L.) (Oxalidaceae), two medicinal plants used in Benin were screened for their antifungal activity against six strains of the genus Aspergillus (Aspergillus fumigatus, Aspergillus flavus, Aspergillus terreus, Aspergillus parasiticus, Aspergillus ochraceus and Aspergillus nidulans). The antioxidant activity and phytochemical constituents were also examined. The extracts were screened for the presence of alkaloids, coumarin, anthracene derivatives, flavonoids, lignans, essential oils, naphtoquinones and terpenoids. The antifungal activity was carried out using agar diffusion method, while antioxidant activity was determined by the 2,2-diphenylpicrylhydrazine method. Phytochemical investigation revealed the presence of flavonoids, anthracenic derivatives, essential oil, pigments, terpene and triterpene in the leaves of O. corniculata and terpene and pigments in the fruits of C. equisetifolia. The antifungal activity of extracts is more marked on the sporulation (17.74 to 99.48%) than the mycelia development (7.69 to 65.71%). Methanol and hydro-ethanol extracts showed the best inhibitory percentage of DPPH radical (78 to 95%). Key words: Medicinal plants, antifungal and antioxidant activity, phytochemical.

This study aimed to estimate and compare the antioxidant potential as well as the levels of heavy metal contamination of Celosia argentea (Amaranthaceae), Launaea taraxacifolia (Asteracea) and Ocimum gratissimum (Lamiaceae) collected in four municipalities of South-Benin by taking into accounts the treatment prior to consumption (precooked and raw). A low extraction yield was obtained during the extraction of leafy vegetables subjected to precooking. The phytochemical screening of Launaea taraxacifolia revealed the presence of triterpenes, steroids, flavonoids and tannins. The phytochemical analysis of Ocimum gratissimum revealed the presence of triterpenes, the steroids, tannins, anthraquinones, coumarins and alkaloids. The analysis of Celosia argentea revealed the presence of triterpenes, steroids, flavonoids, tannins, anthraquinones and alkaloids. The antioxidant activity of the various extracts was found to be dose-dependent. The extracts showed significant antioxidant activities with IC50 ranging from 4.03 to 11.42 µg/ml. Ocimum gratissimum had the strongest antioxidant power followed by Celosia argentea and Launaea taraxacifolia respectively. Pre-cooking of leafy vegetables would have an effect on antioxidant activity, which resulted in a slight increase in the DPPH inhibition power of pre-cooked vegetables compared to raw one. The analysis of heavy metals showed the presence of arsenic, mercury and manganese in the different plant extracts. The highest levels were observed in leafy vegetables collect at Cotonou (Houeyiho) followed by those from Sèmè-Podji but all below the thresholds defined by the World Health Organization. The precooking promoted a decrease of the quantity in heavy metals by leaching, causing low concentration in metals of vegetables precooked in contrast with raw ones.

Fungal infection and aflatoxin contamination were evaluated on 114 samples of dried and milled spices such as ginger, garlic and black pepper from southern Benin and Togo collected in November 2008–January 2009. These products are dried to preserve them for lean periods available throughout the year. Fungal contamination was evaluated after plating on selective media with a total of 20 fungal genera identified, ranging from 7 in garlic to 14 in ginger. Ginger and pepper showed high incidence of fungal contamination compared to garlic that had lower levels of fungal contamination. Species of Aspergillus were dominant on all marketed dried and milled spices irrespective of country. Gene characterization and amplification analysis showed that most of the Aspergillus flavus isolates possess the cluster genes for aflatoxin production. Aflatoxin B1 assessment by Thin Layer Chromatography showed that only garlic (1 sample) and ginger (4 samples) were naturally contaminated with aflatoxin B1 ranging from 390 μg/kg to 1045 μg/kg respectively. Previous reports have mostly highlighted the risk of mycotoxin exposure from staple crops and vegetables in Africa, but such risks now need to be evaluated further for other products such as dried and milled spices.

Chromolaena odorata L (Asteraceae) is a bad invasive plant, found in the humid tropics and sub-tropics worldwide. It is used against dysentery, diarrhea, malaria, wound healing, headache and toothache in traditional medicine. In the present study, we investigated the antibacterial activities of different leaves extracts of Chromolaena odorata L. (cyclohexane, dichloromethane, ethyl acetate and butanol) against four clinical diarrheal strains (Klebsiella oxytoca, Salmonella enterica, Shigella sonnei and Vibrio cholera). We demonstrated that C. odorata leaves extracts show an antibacterial activity between 0.156 and 1.25 mg/mL. Bioassay-guided chromatography by bioautography with iodonitrotetrazolium-based colorimetric assay allowed the isolation and identification of two active compounds. After the combination of RP-HPLC, mass spectrometry analysis, 1D and 2D-NMR spectroscopy, we isolated and characterized two active molecules corresponding to 3’,4’,5,6,7-Pentamethoxyflavone (Sinensetin) and4’,5,6,7-Tetramethoxyflavone (Scutellareintetramethyl ether).

Background Plasmodium vivax is considered to be absent from western Africa, where the prevalence of Duffy-negative red blood cell phenotype proves to be high. Several studies have, however, detected P. vivax infection cases in this part of Africa, raising the question of what is the actual prevalence of P. vivax in local populations. Methods The presence of P. vivax was investigated in a large population of healthy blood donors in Benin using microscopy, serology and molecular detection. The seroprevalence was measured with species-specific ELISA using two recombinant P. vivax proteins, namely rPvMSP1 and rPvCSP1. Specific molecular diagnosis of P. vivax infection was carried out using nested-PCR. The performances and cut-off values of both rPvCSP1 and rPvMSP1 ELISA were first assessed using sera from P. vivax-infected patients and from non-exposed subjects. Results Among 1234 Beninese blood donors, no parasites were detected when using microscopy, whereas 28.7% (354/1234) of patients exhibited had antibodies against rPvMSP1, 21.6% (266/1234) against rPvCSP1, and 15.2% (187/1234) against both. Eighty-four samples were selected for nested-PCR analyses, of which 13 were positive for P. vivax nested-PCR and all Duffy negative. Conclusion The results of the present study highlight an unexpectedly high exposure of Beninese subjects to P. vivax, resulting in sub-microscopic infections. This suggests a probably underestimated and insidious parasite presence in western Africa. While the vaccination campaigns and therapeutic efforts are all focused on Plasmodium falciparum, it is also essential to consider the epidemiological impact of P. vivax. Electronic supplementary material The online version of this article (doi:10.1186/s12936-016-1620-z) contains supplementary material, which is available to authorized users.

Background Acacia ataxacantha is a medicinal specie used extensively in traditional medicine of Benin republic to treat infectious diseases. Our previous study showed interesting antibacterial and antifungal activities against six strains of bacteria and six strains of fungi. The aim of this study was to investigate the antimicrobial and antioxidant activities of compounds isolated from A. ataxacantha. Methods Chromatographic and spectroscopic methods were used to isolate and identify three compounds (1–3) from the bark of A. ataxacantha. Phytochemical investigation of A. ataxacantha (Fabaceae) led to the isolation of three triterpenoids (1–3). The structure of isolated compounds was established by differents spectroscopic methods such as UV, 1H NMR, 13C NMR, 2D NMR and Mass. All isolated compounds were tested for antimicrobial activity using agar disc-diffusion and microdilution methods. The radical scavenging activity of isolated compounds was assessed using 2,2-diphenyl-1-picrylhydrazyl (DPPH) method. Results Phytochemical investigation led to the isolation and identification of lupeol (1), betulinic acid (2) and betulinic acid-3-trans-caffeate (3). Moderate antimicrobial activity was obtained with compound 3 against methicillin-resitant Staphylococcus aureus, Enterococcus feacalis and Pseudomonas aeruginosa with MIC value of 25 μg/ml and Staphylococcus aureus (MIC of 50 μg/ml). Compounds 3 was more active against Staphylococcus epidermidis and Candida albicans with a MIC value of 12.5 μg/ml in boths cases. Compounds 3 had also interesting antioxidant activity with an IC50 of 3.57 μg/ml compared to quercetin (1.04 μg/ml). Conclusion The overall results of this study provide evidence that the compound 3, isolated from A. ataxacantha, exhibit antimicrobial activity against Gram-positive and Gram-negative bacteria and yeast, especially against C. albicans.

Background High risk oncologic Human Papilloma Virus (HPV) is one of the leading causes of cervical cancer worldwide. We investigated HPV genotypes among women living or not with Human Immuno-deficiency Virus (HIV) in two major hospitals in the south of the republic of BENIN in the city of Cotonou. Our objective is to investigate the association of high risk-HPV to cervical dysplasia among women under stringent anti-retroviral (ARV) treatment and in controls without HIV. Methods The investigation was carried out within 1 year period in two groups of adult women: one group with HIV1 infection and under ARV therapy in the National University Hospital (CNHU-HKM) designated as CH group (n = 86); and one control group without HIV infection and attending the hospital Mènontin for routine gynecologic checkup and designated as ME group (n = 86). Cells derived from cervical uterine smears (CUS) were used for this investigation. The samples in ME group were selected to have similar lamin A/C profile with CH group. HPV genotypes were assessed by polymerase chain reaction (PCR) while lamin A/C expression profile was assessed by western blotting to corroborate the risk of cervical dysplasia. Results HPV56 is dominant in CH group while HPV66 is dominant in ME group. 31 % of women in CH group are infected with HPV compared to 23 % in ME group. Quadruple and quintuple HPV infections are more observed among CH group but not in ME group making HPV counts of 43 in CH group and 27 in ME group. Cervical dysplasia are present in 5 % (4/86) of women in CH group and in 1 % (1/86) of women in ME group at the time of CUS collection. The adjustment of the risk to develop cervical cancer in the future related to HPV infection and the total loss of lamin A/C is not significantly different in both groups. Conclusion Women living with HIV are more sensitive to multiple HPV infection but not all HPV infections generated cervical dysplasia. The effectiveness of antiretroviral therapy in CH group may reduce significantly the frequency of cervical dysplasia.

Background Xanthomonas oryzae pv. oryzae (Xoo) is the causal agent of Bacterial Leaf Blight (BB), an emerging disease in rice in West-Africa which can induce up to 50 % of yield losses. So far, no specific resistance gene or QTL to African Xoo were mapped. The objectives of this study were to identify and map novels and specific resistance QTLs to African Xoo strains. Results The reference recombinant inbred lines (RIL) mapping population derived from the cross between IR64 and Azucena was used to investigate Xoo resistance. Resistance to African and Philippine Xoo strains representing different races was assessed on the RIL population under greenhouse conditions. Five major quantitative trait loci (QTL) for resistance against African Xoo were located on different chromosomes. Loci on chromosomes 1, 7, 9, 10 and 11 explained as much as 13 %, 37 %, 13 %, 11 % and 15 % of resistance variation, respectively. A major novel QTL located on chromosome 7 explained 37 % of the phenotypic variance to the African Xoo corresponding to race A3 whereas that on chromosome 11 is effective to all African races tested. Together with genes and QTLs for resistance to bacterial blight previously described, the QTLs described here were mapped onto the reference O. sativa subs japonica (var. Nipponbare) physical map. Conclusion We characterized new resistance QTLs. While some co-localize with known resistance genes/QTLs to Asian strains, others are specific to African strains. We result with new information on genes and QTLs for resistance to bacterial blight that will be useful for controlling the disease.

Sweet potato is one of the most important food security promoted root crops in the world, especially in sub-Saharan Africa. Unfortunately, the crop is still neglected and underutilized in Benin Republic. To establish baseline data for its better utilization for upgrading its value chain, 10 selected local varieties (01 cream, 02 white, 03 yellow, and 04 orange flesh-colored) were compared for their macro-nutritional composition assessed using standard Association of Official Analytical Chemists (AOAC) procedures and spectrophotometry methods. The results indicate that sweet potato dry matter, protein, fiber, and ash content ranged from 46.11 to 25.9%, 4.09 to 1.97%, 1.81 to 3.00%, and 4.70 to 2.56%, respectively and orange flesh cultivars were found very rich. Pearson correlation analysis of variables revealed that dry mater content is positively correlated with carbohydrate and energy values, but negatively correlated with ash and fiber content, while starch content is strongly correlated with fiber content. Principal component analysis allowed us to classify the sweet potato varieties into 03 varietal groups among which Group 2 (05 varieties) exhibited rich fiber, ash, and protein contents and may be recommended for infant foods formulations. These results constitute important orientation for sweet potato processing chain organization in Benin and for the establishment of future nutrition and breeding programme. Key words: Benin, sweet potato, Ipomoea batatas, nutritional composition, orange flesh cultivar, value chain.

Schrankia leptocarpa DC. (Mimosaceae) is an African medicinal plant, traditionally used by plants practitioners in Benin to cure malaria, diarrhea and stomach ache. There is little ethnobotanical and almost no chemical information available for this species. Eight extracts from the entire plant of Schrankia leptocarpa were prepared using diethyl ether, acetone, cyclohexane, methylene chloride, ethyl acetate, methanol, butanol and ethanol/water (20:80). Phytochemical analysis were performed and antibacterial was evaluated against four reference bacteria, Staphylococcus aureus , Enteroccocus feacalis , Escherichia coli and Pseudomonas aeruginosa , and four patient isolated bacteria using iodonitrotetrazolium microtest. The antioxidant properties were investigated using 2,2-diphenyl-2-picrylhydrazyl (DPPH) and superoxide anion radical scavenging activity. All extracts showed antimicrobial activity ranging from 0.078 to 5 mg/ml against one or more bacteria. The most potent extract was the diethyl ether extract with a minimum inhibitory concentration value of 75 μg/ml on E. faecalis . Phytochemical screening showed a wide variety of phytoconstituents such as steroids, terpenes, phenolic acid, flavonoids, tannins and alkaloids. The DPPH radical scavenging activity indicated that the radical scavenging activity ranged from 1.35 to 3.47 μg/ml. The superoxide anion radical scavenging showed inhibitory percentage ranging from 32.04 to 86%. Higher activity was observed with ethyl acetate extract. The results provide an evidence for the traditional use of S. leptocarpa for the treatment of infective diseases. Keywords: Schrankia leptocarpa , antibacterial, antioxidant, 2,2-diphenyl-2-picrylhydrazyl (DPPH), superoxide anion