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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: 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.

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.

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 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 is a medicinal species use traditionally in Benin to treat malaria. A previous study showed interesting antimalarial activity against two strains of Plasmodium falciparum . Phytochemical investigation of S. leptocarpa DC. (Mimosaceae) led to the isolation of two diarylheptanoids ( 1 – 2 ), three phenolic acid ( 3 – 5 ), one p-coumaric acid derivate ( 6 ) and three flavonoids ( 7 – 9 ). The structures of the isolated compounds were established by combination of spectroscopic methods. All isolated compounds were tested in vitro for antiprotozoal activity against P. falciparum , Trypanosoma brucei rhodesiense , Trypanosoma cruzi , and Leishmania donovani . Compounds 1 and 2 showed trypanocydal and antiplasmodial activities in the micromolar range. Compound 1 showed also strong submicromolar trypanocidal activity against T. b. rhodensiense with an IC 50 value of = 0.79 ± 0.3 μM.

Thirty five villages randomly selected across ethnic and agro-ecological zones of Benin were surveyed to document the indigenous knowledge associated with the domestication (bringing into cultivation), production and utilization of vegetable Gbolo (Crassocephalum spp.). The study revealed the existence of different morphotypes (1–4 per village) corresponding to two botanical species (Crassocephalum rubens (Juss. ex Jacq.) S. Moore) and (Crassocephalum crepidioides (Benth.) S. Moore) found unequally distributed throughout the country. The domestication (bringing into cultivation from the wild) of Gbolo was started in many villages and with some tribes in southern Benin, the vegetable is already being produced in sole cropping for commercial purposes. Regular consumption (49.90 % of responses) and scarcity (20.30 % of responses) were the two main reasons attributed by the interviewees for domestication of the vegetable. The cultural practices recorded were of five categories. The commonest cropping system found was mixed or inter-row cropping (92.31 % of producers) with either vegetable crops (53.85 % of producers) or non-vegetable crops (38.46 % of users). Sauce prepared with either fresh or dried leaves was the main type of preparation of Gbolo and the vegetable was reported to possess special nutritional and medicinal values. For further promotion, important researches directions are suggested.

Traditional leafy vegetables (LFT) are plants whose leaves are used and consumed by local human populations. Africa is an enormous reservoir of diversity for those vegetables which participate to food security, nutrition and monetary income in both rural and urban areas. The leafy vegetables are rich in fibres, vitamins and minerals. But intensive and repeated harvesting of the LFT in Africa results in their increasing rarity. Among endogenous leafy vegetables recorded in Benin, Sesamum radiatum Schumach. & Thonn. (Pedaliaceae) is a species commonly consumed by many ethnic groups. During plant development, quantitative and qualitative modifications occur, such as an increase in stem size and the production of leaves, flowers, fruit and grains To contribute to a better understanding of the breeding system and phenology for in situ and ex situ conservation of S. radiatum, we conducted both on-station and on-farm experiments. The on-station experiment was conducted at the International Institute of ...

The dichloromethane, methanol and hydroethanolic extracts from leaves of Vitex donianaand stem bark of Adansonia digitata have been investigated for their antibacterial, antifungal, antioxidant activities and toxicity. The antifungal activity has been investigated against six species of Aspergillus by measuring the mycelial and sporulation inhibitions. The antimicrobial activity was investigated against six Gram positive and Gram negative strains using the microplate dilution method. The phytochemical study was performed on thin layer chromatography and antioxidant activity was measured using 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging test. The sporulation inhibition percentage was 70% while mycelial inhibition was less than 40%. The minimum inhibitory concentration ranged from 0.039 to 2.5 mg/ml. In DPPH radical scavenging assay, the effect on reducing free radicals increased in a dose dependent manner. Three extracts out of six were very active compared to quercetol, with inhibition percentage ranging from 77.39 to 86.55%. The results supported the utilization of these plants in infectious diseases and also showed these plants as good sources for antioxidants. Key words: Antifungal, antibacterial, antioxidant, Adansonia digitata, Vitex doniana.

Mycotoxins contamination in some agricultural food commodities seriously impact human and animal health and reduce the commercial value of crops. Mycotoxins are toxic secondary metabolites produced by fungi that contaminate agricultural commodities pre- or postharvest. Africa is one of the continents where environmental, agricultural and storage conditions of food commodities are conducive of Aspergillus fungi infection and aflatoxin biosynthesis. This paper reviews the commodity-wise aetiology and contamination process of aflatoxins and evaluates the potential risk of exposure from common African foods. Possible ways of reducing risk for fungal infection and aflatoxin development that are relevant to the African context. The presented database would be useful as benchmark information for development and prioritization of future research. There is need for more investigations on food quality and safety by making available advanced advanced equipments and analytical methods as well as surveillance and awareness creation in the region.

Studies conducted in Benin, in which the main staple foods are maize, cassava, groundnuts and yams, showed high levels of aflatoxin residues in blood of the exposed population. The natural contamination with fungi and aflatoxins in cassava chips sold at markets in Benin, West Africa was investigated. A total of sixty samples were sampled from open markets in 11 districts of 3 agroecological zones and analyzed for the presence of mycoflora and aflatoxin B 1 , B 2 , G 1 and G 2 . Fourteen genera of fungi were associated with marketed dried cassava chips. Within these, twenty- two isolates were identified to species level, whereas four were identified only to genus. The dominating fungal species isolated were Rhizopus oryzae , Nigrospora oryzae , Chrysonilia sitophila , Cladosporium resinae , Cladosporium herbarum , Apergillus niger and Aspergillus flavus . Fifty-four out of sixty samples were contaminated with A . flavus . The rate of occurrence in CFU/g of A. flavus fungi was lower than for all other fungal species together. Aflatoxin was not detected in any of the samples analyzed using HPLC with post-column photochemical derivatization and fluorescence detection. The limit of detection (LOD) was 0.1 μg/kg. Results from this study suggest cassava chips are unlikely to be a source of aflatoxin in Benin, and that other staples such as maize and groundnuts are more important in aflatoxin exposure. Therefore it can be speculated that staples like maize and groundnut are more important in aflatoxin exposure.

Background: Genomewide association studies have shown a relation between plasma vitamin B-12 concentration and the 461G/A polymorphism of fucosyltransferase 2 (FUT2), a gene associated with susceptibility to Helicobacter pylori infection. Objective: We evaluated in 2 populations the association of FUT2 461 G/A polymorphism with vitamin B-12 and related metabolic markers and investigated whether the influence of FUT2 on H. pylori serology is part of the mechanisms that underlie these associations. Design: The study included 1282 ambulatory subjects from Europe and West Africa. Blood concentrations of vitamin B-12, folate, homocysteine, and methylmalonic acid were measured. Genotyping was performed by real-time polymerase chain reaction. H. pylori serology testing was performed by using ELISA. Results: In univariate analysis, FUT2 461 A/A genotype was associated with higher plasma vitamin B-12 concentration in the total population (P = 0.0007) as well as in Europe (P = 0.0009) and in West Africa (P = 0.0015). Positivity for H. pylori serology was higher in West Africa (P , 0.0001) and was not associated with low plasma vitamin B-12. The prevalence of H. pylori‐positive patients did not differ among FUT2 461 G/A genotypes (P = 0.2068). In multivariate analysis, FUT2 461 G/A genotype (P = 0.0008), but not positive H. pylori serology, was an independent predictor of plasma vitamin B-12 concentration. Conclusion: This study confirms the influence of FUT2 461 G/A polymorphism on plasma vitamin B-12 concentration and showed no influence of H. pylori serologic status on this association in ambulatory subjects from Europe and West Africa. Am J Clin Nutr 2012;95:514‐21.

Leafy vegetables are sources of diet diversification and could contribute to food and nutritional security in African rural areas. However, in some places, little is known about if, how, and why leafy vegetables are consumed. Processing and preservation methods, food forms, and consumption determinants of four leafy vegetables (Sesamum radiatum, Ceratotheca sesamoïdes, Acmella uliginosa and Justicia tenella), known to contribute to the diet of rural populations in the Center and Northern parts of Benin, were investigated. Three hundred randomly selected households were investigated, using rapid appraisal and quantitative survey methods, descriptive statistics and correspondence analysis. Processing methods to prepare sauces varied depending on sociocultural groups. Cooking of fresh leaves predominated, while sun drying was the usual practice of preserving these leafy vegetables. Consumption frequencies were associated with sociocultural groups, food habits, and availability in living areas.

Coumarins have been found in many plant species and some have antimicrobial and antifungal activities as well as pharmacological effects. Scopoletin (6-methoxy-7-hydroxycoumarin) is a coumarin compound with antifungal properties that has been isolated from several plant species. Although it is not yet fully understood, the biosynthesis of scopoletin is described. In addition, its induction upon attack by pathogens and abiotic stress as well as its inhibitory effects on bacteria and fungi are summarized in this review. The scientific information on the inhibitory effect of scopoletin on storage fungi is scarce.

The scopoletin level in a cassava variety from Benin, BEN 86052, and the compounds effect on the growth of an Aspergillus flavus isolate from cassava chips were investigated. The influence on the biosynthesis of aflatoxins was also investigated. Scopoletin was quantified using high performance liquid chromatography. An in vitro test was used to evaluate the inhibitory effects of cassava flour extracts and pure scopoletin on growth and biosynthesis. The A. flavus isolate was genetically characterized to be an aflatoxin producer using polymerase chain reaction. Scopoletin was found in roots and chips with a level ranging from 4.9 to 242.5 mg/kg dry weight. Scopoletin induction was noticed after a peeling and drying process (6 days). Aflatoxin production by a strain of A. flavus holding the cluster Nor1, Omt1 and OmtB responsible for aflatoxin biosynthesis was inhibited by scopoletin and cassava flour at lower concentrations (0.024 mM). Scopoletin could be used on other commodities susceptible to mycotoxin contamination. PRACTICAL APPLICATIONS Scopoletin accumulated in cassava variety used for chips production. Scopoletin inhibited the production of aflatoxin by toxigenic Aspergillus flavus. The use of this compound on other crops susceptible to fungi infection and aflatoxin contamination could be investigated to reduce food spoilage and mycotoxin contamination.

Xanthomonas oryzae pv. oryzae is the causal agent of bacterial blight in rice, one of the most devastating diseases of rice worldwide. African X. oryzae pv. oryzae strains belong to a clear genetic group distinct from those of Asia. Three new races of the pathogen were characterized among strains from West Africa. We evaluated 107 Oryza glaberrima accessions for resistance to bacterial blight under greenhouse conditions. Six-week-old seedlings were inoculated with five different African X. oryzae pv. oryzae strains originating from the West African nations of Burkina and Mali and representing different races (A1, A2, and A3). Philippine X. oryzae pv. oryzae strain PXO86 (race 2) was also used. Most (48%) of the accessions of O. glaberrima were highly susceptible to X. oryzae pv. oryzae strains from Burkina, while 20 and 36 were resistant to X. oryzae pv. oryzae strains from Mali and the Philippines, respectively. CAPS markers and dot blot assays were used for detection of resistance genes xa5 and Xa21 from a selected set of O. glaberrima accessions. Our results suggest that the O. glaberrima germplasm contains a narrow genetic base for resistance to X. oryzae pv. oryzae. Sources of resistance identified among O. glaberrima are recommended for rice breeding programs to develop bacterial blight-resistant cultivars for West Africa.

Background/Aims Homocysteine metabolism is linked to DNA methylation, a mechanism potentially involved in the course of hepatitis B virus (HBV) infection. We evaluated the association of determinants of homocysteine metabolism with the outcome of HBV infection. Methods Four hundred and fifty-five healthy adults from Togo and Benin were tested for HBV serologic markers, HLA DR alleles, folate, vitamin B12, methylenetetrahydrofolate reductase (MTHFR) 677 C→T, 1298 A→C and methionine synthase 2756 A→G polymorphisms. Results Seventy-eight percent of the study population was anti-HBc positive. Among them, 202 (56.9%) were anti-HBs positive and 58 (16.3%) were HBsAg positive. After stepwise logistic regression, the MTHFR 677 T allele was independently associated with persistence of detectable anti-HBs antibodies (OR: 2.47; 95% CI: 1.29–4.71; p =0.006). The mean HBV DNA level was significantly lower in HBsAg positive subjects carrying the 677 T allele than in those with the 677 CC genotype (1000±1406 vs. 2,400,000±214,000 copies/ml, p =0.005). Beninese origin and HLA-DRB1*09 allele were the other determinants independently associated with favorable outcome of HBV infection. Conclusions The methylenetetrahydrofolate reductase 677 T allele seems to protect against chronic HBV infection in young African adults.

Thalia geniculata L. (Marantaceae) is an African medicinal plant traditionally used in Benin to treat malaria and other parasitic diseases. There is little ethnobotanical and almost no chemical information available for this species. The phytochemical analysis of the aerial parts of the plant led to the isolation of five compounds, identified as sitoindoside I [β-sitosterol-(6-O-hexadeca-noyl)3-O-β-D-glucoside] (1), daucosterol β-sitosterol-3-0-β-Dglucoside (2), stigmasterol (3), β-sitosterol (4), and geranylfarnesol (5). The structural elucidation was achieved using spectrometric methods and by comparison with the literature. Biological activity was evaluated against Plasmodium falciparum, Trypanosoma rhodesiense, Trypanosoma cruzi, and Leishmania donovani. Geranylfarnesol (5) showed significant antiprotozoal activity against P. falciparum and L. donovani, with IC50 values of 12.7 and 13.2 µM, respectively.

Staphylococcus aureus infections are widely prevalent in West Africa and are often associated with urinary tract infections (UTIs). Virulence factors from S. aureus have rarely been described for such infections. The purpose of the current study was to determine the prevalence of toxins and adhesion factors obtained from S. aureus isolated from presumed primary UTIs at the Cotonou University Hospital (CUH) in Benin as compared with the Strasbourg University Hospital (SUH) in France. Both ambulatory and hospitalised patients were included in the study. Sixty-five independent strains of S. aureus from CUH and 35 strains from SUH were obtained over a four-month period. Virulence factors were characterised by immunodetection or multiplex polymerase chain reaction, and meticillin susceptibility was recorded. Approximately 50% of all isolates produced at least one enterotoxin. No isolate from SUH produced Panton-Valentine leucocidin (PVL), whereas 21.5% of the S. aureus isolates from CUH produced PVL (P

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

Background Acmella uliginosa (Asteraceae) is a flowering plant whose leaves are consumed as a vegetable in Benin. They are also traditionally used as an antibiotic in the treatment of infectious diseases. To evaluate the therapeutic potential and toxicity effect of this leafy-vegetable, the antibacterial, antifungal, antioxidant activities and, toxicity and phytochemical constituents were investigated. Methods Dichloromethane, methanol and aqueous extracts of Acmella uliginosa were evaluated for their antimicrobial activity against six bacterial and six fungi strains. Antibacterial and antifungal activities were investigated by microdilution method and agar diffusion method respectively. Antioxidant activity was assessed using the 2,2-diphenyl-1-picryl-hydrazyl assay and phytochemical screening was carried out using standard procedures. Finally, oral acute toxicity at a dose of 2000 mg/kg was done according to the Organization for Economic Co-operation and Development guideline n° 423. Results The antibacterial activity was broad spectrum, inhibiting both Gram-positive and Gram-negative bacteria. The minimum inhibitory concentration ranged from 0.625 to 5 mg/ml. The antifungal evaluation show that all the extracts inhibited mycelial growth and sporulation of fungi with percentages of inhibition ranging from 9.39 to 75.67 % and 22.04 to 99.77 %, respectively. In DPPH radical scavenging assay, the effect on reducing free radicals increased in a dose dependent manner. The percentage of inhibition of DPPH ranged from 0.94 to 73.07 %. Phytochemical screening revealed the presence of coumarin, flavonoid, naphtoquinone, anthracene derivative, saponin, lignan, triterpene and tannin. The dichloromethane and methanol extracts showed the best biological activities; they were also shown as the best extraction solvents of phytochemicals. In the acute toxicity evaluation, all animals were physically active and no deaths of rats were observed during the test. However, the aqueous extract promoted biochemical, hematological and histopathological alterations of treated rats at 2000 mg/kg body weight. Conclusion A. uliginosa extracts contains antimicrobial, antioxidant agents and was not lethal for rats when ingested. However, according to the results obtained for biochemical, hematological, and histopathological analysis, caution is required regarding its consumption.

In order to evaluate genetic variability of agro-morphological traits and also determine the correlation between grain yield with its components in rice lines, 17 recombinants inbred lines, their parents and a check variety were grown in research station of Africa rice center in Benin republic during two consecutive years 2013 and 2014. The experiments were laid out in a randomized complete block design with four replications. Phenotypic coefficients of variance were higher than genotypic coefficients of variance in all the characters across the two years. High heritability in broad sense (H2) estimates were obtained for biomass (68.77%), date of 50% flowering (98.11%), plant height (81.94%), leaf area (82.90%), number of panicles (64.40%), leaf dry weight (72.91%), root weight (67.43%) and yield/plant (62.23%) suggesting that the traits were primarily under genetic control. A joint consideration of broad sense heritability (H2) and genetic advance as per cent mean expected (GAM) revealed that leaves dries weight and roots weight combined high heritability and high GAM. Furthermore, high (H2) and high GAM recorded in these characters could be explained by additive gene action. However, high estimates (H2) combined with moderate GAM recorded for biomass, day to 50% flowering, leaf area, number of panicle and yield/plant could be due to non-additive gene effect. Grain yield/plant recorded positive and significant correlation with stem weight (r=0.5262) and biomass (r=0.9291). This result indicates that selection based on these two characters will be highly effective for yield improvement in rice. Key words: Agro-morphological traits, correlation, genetic variability, heritability, rice.

Background: A 776C>G variant (dbSNP ID: rs1801198) in the transcobalamin gene (TCN2; MIM# 275350) decreases the cellular and plasma concentration of transcobalamin and thereby influences the cellular availability of vitamin B12. Objective: To evaluate the world-wide prevalence of this variant and its association with homocysteine plasma level. Methods: The study was performed in 1433 apparently healthy subjects, including Afro-Americans and Afro-Africans and in 251 Afro-Africans subjects with severe malaria. Results: The frequencies of 776G allele were the highest in China (0.607 [95% confidence interval:0.554-0.659]), low in West Africa (Benin and Togo, 0.178 [0.154-0.206]) and intermediate in France (0.445 [0.408-0.481]), Italy (0.352 [0.299-0.409]), Marocco (0.370 [0.300-0.447]) and Mexico (0.374 [0.392-0.41.9]). The 776GG genotype was more frequent in Afro-Americans from New York (16.7 [8.4-30.7]) and in Afro-African patients with severe malaria (6.0% [95%CI: 3.7-9.6]) than in healthy Afro-African volunteers (p=0.0004 and p=0.0329, respectively), while no difference was observed for MTHFR 677TT and 677T allele. A disequilibrium of TCN2 genotype distribution was recorded in the patients with severe malaria, with a 2-fold higher GG genotypes than expected (p=0.010). An association between the TCN2 polymorphism and homocysteine was observed only in Mexico and France, the two countries with the highest rate of low plasma concentration of vitamin B12 (

Antibodies that impede the invasion of Plasmodium falciparum (P. falciparum) merozoites into erythrocytes play a critical role in anti-malarial immunity. The Growth Inhibition Assay (GIA) is an in vitro measure of the functional capacity of such antibodies to limit erythrocyte invasion and/or parasite growth. Up to now, it is unclear whether growth-inhibitory activity correlates with protection from clinical disease and there are inconsistent results from studies performed with GIA. Studies that have focused on the relationship between IgGs and their in vitro parasite Growth Inhibition Activity (GIAc) in infants aged less than two years old are rare. Here, we used clinical and parasitological data to precisely define symptomatic or asymptomatic infection with P. falciparum in groups of infants followed-up actively for 18 months post-natally. We quantified the levels of IgG1 and IgG3 directed to a panel of candidate P. falciparum vaccine antigens (AMA-1, MSP1, 2, 3 and GLURP) using ELISA and the functional activity of IgG was quantified using GIA. Data were then correlated with individuals' infection status. At 18 months of age, infants harbouring infections at the time of blood sampling had an average 19% less GIAc than those not infected (p=0.004, multivariate linear regression). GIAc decreased from 12 to 18 months of age (p=0.003, Wilcoxon matched pairs test). Antibody levels quantified at 18 months in infants were strongly correlated with their exposure to malarial infection, however GIAc was not correlated with malaria infectious status (asymptomatic and symptomatic groups). In conclusion, both infection status at blood draw and age influence parasite growth inhibition mediated by IgG in the GIA. Both factors must be taken into account when correlations between GIAc and anti-malarial protection or vaccine efficacy have to be made.

Cassava is one of the staple food crops contributing significantly to food and nutrition security in Benin. This study aimed to assess the diversity of the elite cassava cultivars of Bantè district, determine the physicochemical properties of the most preferred ones as well as the sensory attributes of their major derived products (gari and tapioca), and compare them with the farmers’ and processors’ perception on their technological qualities. The ethnobotanical investigation revealed existence of 40 cultivars including 9 elites that were further classified into three groups based on agronomics and technological and culinary properties. Clustered together, cultivarsIdilèrou, Monlèkangan,andOdohoungbocharacterized by low fiber content, high yield of gari and tapioca, and good in-ground postmaturity storage were the most preferred ones. Their physicochemical analysis revealed good rate of dry matters (39.8% to 41.13%), starch (24.47% to 25.5%) and total sugars (39.46% to 41.13%), low fiber (0.80% to 1.02%), and cyanide (50 mg/kg) contents. The sensory analysis of their gari and tapioca revealed very well appreciated (taste, color, and texture) products by the consumers. The confirmation by scientific analysis of the farmers’ perception on qualities of the most preferred cultivars indicated that they have good knowledge of their materials.

Background: Methylenetetrahydrofolate reductase (MTHFR) 677C→T polymorphism is heterogeneously distributed worldwide, with the highest and lowest frequencies of the T allele in Mexico and Africa, respectively, and a south-to-north gradient in Europe. Distribution of MTHFR 1298A→C is less well known. It has been hypothesized that 677T frequency could result in part from gene-nutrient interactions. Objective: The objective was to compare the association of 677T and 1298C alleles with plasma concentrations of homocysteine, folate, and vitamin B-12 in geographical areas with contrasting 677T allele frequencies. Design: Healthy young adults (n = 1:277) were recruited in Mexico City, the West African countries of Benin and Togo, France, and Sicily (Italy). Homocysteine, folate, and vitamin B-12 were measured in plasma, and MTHFR polymorphisms were measured in genomic DNA. Results: Mexico City and Sicily reported the highest and Benin and Togo reported the lowest plasma concentrations of folate. Mexico City had the highest 677T allele prevalence and the lowest influence of 677TT genotype on homocysteine, whereas the opposite was observed in Africa. The prevalence of the 1298C allele was lowest in the Mexicans and Africans and highest in the French. The percentage of the 677T genotype was significantly associated with the folate concentrations in 677CC carriers in a u nivariate analysis (R = 0.976; 95% CI: 0.797, 0.996; P < 0.0002) and in a multiple regression model that included homocysteine, vitamin B-12, and age (P = 0.0002). Conclusion: Our data agree with the hypothesis of a gene-nutrient interaction between MTHFR 677C→T polymorphism and folate status that may confer a selective advantage of TT-homozygous genotype when dietary intake of folate is adequate, at least in the areas studied.