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Malaria is a parasitic disease caused by a hematozoan of the genusA total of 142The successful rates of amplification ofDespite the limited number of samples analyzed, our study highlighted the circulation of isolates carrying both the mutant

The aim of this study was to assess the antibacterial potential of Albizia mahalao, a Madagascar Fabaceae. Leaf methanolic extracts (LME), root bark methanolic extract (RME), stem bark methanolic extract (SME), and alkaloids extracted from leaves under basic and acidic conditions were used. All the methanol extracts contained alkaloids and saponins. The antimicrobial activity was tested against many bacteria spp. including; Listeria monocytogenes, Staphylococcus aureus, Clostridium perfringens, Enterobacter aerogenes, Salmonella enterica, Shigella flexneri, and Vibrio fischeri, using the Disc diffusion and the Microdilution assays. With the exception of the SME which is inactive, the other extracts exhibited broad spectrum potential against all the tested bacteria. The alkaloids are efficient against nearly all the bacteria under both of the basic and acidic conditions, with an inhibition zone diameter (IZ) of >17 mm, and minimum inhibitory concentration (MIC) of 12000 µg/ ml) is the more resistant species. The majority of the extracts expressed bactericidal potency against the tested bacterial spp. Current results revealed the antibacterial potential of the Albizia mahalao leaves and root bark extracts thus could be used to treat infectious diseases.

The present work aimed to study the composition and antimicrobial properties of the essential oil ofHelichrysum ibityenseleaves (HIEO). HIEO was extracted by hydrodistillation from fresh leaves with a yield of 1.9%. It had a relative density of 0.9247 at 20℃, a refractive index of 1.4706, an optical rotation of -0°33, an acid index of 2.10 and an ester index of 54. Gas chromatography analysis/flame ionisation detection of HIEO had identified 17 components, representing more than 99.54% of the overall composition of the HIEO including 1.8-cineole (69.46%) the major component, α-terpinene (4.62%), β-caryophyllene (4.39%), α-pinene (4.13%), β-pinene (2.96%), p-cymene (2.39%) and γ-terpinene (2.16%). The HIEO antimicrobial activity was tested against nine pathogenic bacteria includingStaphylococcus aureus, Staphylococcus pneumoniae,Streptococcus pyogenes, Clostridium perfringens, Bacillus cereus, Pseudomonas aeruginosa, Enterobacter cloacae, Enterobacter aerogenes, Yersinia enterocolitica,andCandida albicansusing the Disc diffusion and the Microdilution assays. HIEO exhibited broad activity spectrum and high microbial activity with inhibition zones (IZ) ranging from 12 to 35 mm. OnBacillus cereus, the most sensitive bacterium, its Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) were 9.37 mg/ml and 13.22 mg/ml respectively. With an MBC/MIC ratio of 1.41, HIEO exerted a bactericidal action onBacillus cereus. When administered orally to mice at 1000 mg/kg body weight, HIEO caused symptoms of intoxication which disappeared after 24 h. These preliminary results revealed HIEO could be used to treat different infectious diseases if its safety will be confirmed.

Seeds of Crotalaria cleomifolia (Fabaceae) are consumed in Madagascar in preparation of popular beverages. The investigation of extracts from the seeds of this species revealed the presence of high amounts of alkaloids from which two pyrrolizidine-derived alkaloids were isolated. One of them was fully characterized by spectroscopic and spectrometric methods, which was found to be usaramine. Owing to the high toxicity of these alkaloids, issuing a strong warning among populations consuming the seeds of Crotalaria cleomifolia must be considered.

Background: Timely and accurate identification of uropathogens and determination of their antimicrobial susceptibility is paramount to the management of urinary tract infections (UTIs). The main objective of this study was to develop an assay using LAMP (Loop mediated isothermal amplification) technology for simple, rapid and sensitive detection of the most common bacteria responsible for UTIs, as well as for the detection of the most prevalent genes (encoding cefotaximases from CTX-M group 1) responsible for resistance to 3rd generation of cephalosporins. Method: We designed primers targeting Proteus mirabilis, while those targeting Escherichia coli, Klebsiella pneumoniae and Enterococcus faecalis and the CTX-M group 1 resistance gene were benchmarked from previous studies. The amplification reaction was carried out in a warm water bath for 60 min at 63±0.5 °C. The amplicons were revealed by staining with Sybr Green I. Specificity and sensitivity were determined using reference DNA extracts spiked in sterile urine samples. The analytical performance of the assays was evaluated directly on pellets of urine samples from patients suspected of UTI and compared with culture.Results: We found a high specificity (100%) for LAMP assays targeting the selected bacteria (P. mirabilis, E. coli, K. pneumoniae, E. faecalis) and the CTX-M group 1 when using DNA extracts spiked in urine samples. The sensitivities of the assays were around 1.5 103 Colony Forming Units (CFU) /mL corresponding to the cut-off value used to define bacteriuria or UTIs in patients with symptoms. Out of 161 urine samples tested, using culture as gold standard, we found a sensitivity of the LAMP techniques ranging from 96 to 100 % and specificity from 95 to 100 %.Conclusion: We showed that the LAMP assays were simple and fast. The tests showed high sensitivity and specificity using a simple procedure for DNA extraction. In addition, the assays could be performed without the need of an expensive device such as a thermal cycler. These LAMP assays could be useful as an alternative or a complementary tool to culture reducing the time to diagnosis and guiding for more effective treatment of UTIs but also as a powerful diagnostic tool in resource-limited countries where culture is not available in primary health care structures.

Klebsiella pneumoniae can lead to a wide range of diseases including pneumonia, bloodstream and urinary tract infections. During a short period of a pulmonary plague epidemic in October 2017 in Madagascar, 12 K. pneumoniae isolates were identified in ten sputum and two buboes aspirate samples. These isolates were from 12 patients suspected of plague, without epidemiological relationships, but were negative for Yersinia pestis in culture. Data were collected from the plague national surveillance system. The isolates were characterized by antimicrobial susceptibility testing and whole-genome sequencing. Real-time PCR was performed to confirm the presence of K. pneumoniae DNA in buboes. All isolates were identified as K. pneumoniae sensu stricto. Five isolates were extended-spectrum β-lactamases producers; eleven different sequence types were identified. Five isolates belonged to known hypervirulent sequence types. Our results demonstrate community-acquired pneumonia caused by K. pneumoniae isolates in patients suspected of plague stressing the importance of bed-side differential diagnosis.

Background Assessment of the genetic diversity of Plasmodium falciparum parasites from various malaria transmission settings could help to define tailored local strategies for malaria control and elimination. Such assessments are currently scarce in Madagascar. The study presented here aimed to bridge this gap by investigating the genetic diversity of P. falciparum populations in three epidemiological strata (Equatorial, Tropical and Fringes) in Madagascar. Methods Two-hundred and sixty-six P. falciparum isolates were obtained from patients with uncomplicated malaria enrolled in clinical drug efficacy studies conducted at health centres in Tsaratanana (Equatorial stratum), Antanimbary (Tropical stratum) and Anjoma Ramartina (Fringes) in 2013 and 2016. Parasite DNA was extracted from blood samples collected before anti-malarial treatment. Plasmodium species were identified by nested PCR targeting the 18 S rRNA gene. The genetic profiles of P. falciparum parasites were defined by allele-specific nested PCR on the polymorphic regions of the msp-1 and msp-2 genes. Results Fifty-eight alleles were detected in the P. falciparum samples tested: 18 alleles for msp-1 and 40 for msp-2. K1 (62.9%, 139/221) and FC27 (69.5%, 114/164) were the principal msp-1 and msp-2 allele families detected, although the proportions of the msp-1 and msp-2 alleles varied significantly between sites. Polyclonal infections were more frequent at sites in the Equatorial stratum (69.8%) than at sites in the Tropical stratum (60.5%) or Fringes (58.1%). Population genetics analyses showed that genetic diversity was similar between sites and that parasite flow within sites was limited. Conclusions This study provides recent information about the genetic diversity of P. falciparum populations in three transmission strata in Madagascar, and valuable baseline data for further evaluation of the impact of the control measures implemented in Madagascar.

This study is aimed at the assessment of antimicrobial potential of Albizia masikororum, a Malagasy Fabaceae. Hexanic and methanolic extracts from fruit pods, stem bark, leaves and seeds were tested by disc diffusion and microdilution methods on 10 pathogenic microorganisms including four Gram positive bacteria, five Gram negative bacteria and one yeast. Only the leaf and seed methanolic extracts, LME and SME respectively, were active on some bacteria. LME and SME had a broad-spectrum activity, with SME more effective. The minimum inhibitory concentration (MIC) values of both extracts were

Comoros Union presents a considerable biodiversity of food resources that are neglected or still not valorised, as breadfruit. This study aimed to evaluating nutritional and nutraceutical traits of Artocarpus altilis (Parkinson) Fosberg by characterizing its main bioactive compounds, nutritional traits, and antioxidant properties in order to contribute to the development of traditional and innovative uses of this species as functional food (e.g., infant flour). Bioactive compound composition, antioxidant properties, protein and sugar content, lipids, fibre, and macro- and microelements were observed in these fruits after a specific drying process. Breadfruit showed positive nutritional traits. The main identified phenolic groups were cinnamic acids (with a maximum of 51.88 ± 2.63 mg/100 gDW for chlorogenic acid) and tannins. The highest value of antioxidant activity was 6.40 ± 1.02 mmol·Fe2+/kgDW. This preliminary phytochemical investigation may provide a contribution to the identification and quantification of lead compounds responsible for traditional nutritional and therapeutic claims.

Previous phytochemical studies have shown that the plants of the Albizia genus (Fabaceae) contain bioactive saponins, lignans, spermine alkaloids, flavonoids, glycosides phenols and pyridoxine derivatives. Their extracts sometimes display medical properties, but can have also toxic effects. The purpose of our study was to determine the in vivo toxicity of Albizia bernieri seeds in the experimental model of the medaka fish embryo, which is recommended for use in toxicity studies. Our results show clearly that incubating the embryos or larvae of the medaka fish in a medium containing A. bernieri extracts caused a dose-dependent reduction in embryo or larvae survival. Embryos exposed to an extract of A. bernieri displayed cerebral lesions, such as cell lysis and the emergence of lysosomes in the glial tissue. We conclude that when comparing with data obtained with different plant extracts tested on medaka development in our laboratory, A. bernieri displays an unusually high toxicity. Focussing on the cerebral target as well as the fish behaviour could bring more specific informations.

This work was designed to study the antimicrobial activity of Crotalaria bernieri Baill. (Fabaceae). Extracts from leaf, root, pod and seed using hexane, ethyl acetate and methanol were tested in vitro for their activity against 17 bacteria, 5 fungi (3 yeasts and 2 molds) using disc diffusion and micro dilution methods. At the concentration of 1 mg/disc, all the extracts exhibited antimicrobial activity depending on the plant part and the extraction method used. The most sensitive germs were Salmonella enteridis, Streptococcus pyogenes and Candida guilliermondii with inhibition zone diameter (IZD) of 11 mm, 15 mm and 13 mm respectively. Most of extracts showed, broad activity spectrum varying from one extract to another. Minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and minimum fungicidal concentration (MFC) of all extracts were recorded. Ten extracts displayed an excellent effect (MIC 1000 µg/ml). Leaf methanol extracts were the most efficient and Gram positive bacteria the most sensitive. All extracts had bactericidal (MBC/MIC ≤ 4) or fungicidal action (MFC/MIC ≤ 4) in certain microorganisms and bacteriostatic (MBC/MIC > 4) or fungistatic action (MFC/MIC > 4) in others. Antimicrobial activity might be due to tannins, polyphenols, steroids, triterpenes and flavonoids that were present in most of the plant organs, but alkaloids in leaf and pod and saponosides in root might also be involved. C. bernieri with the effectiveness of all its parts, the variety of its secondary metabolites, the great number of sensitive pathogen microorganisms and its ubiquity make this plant species an interesting source of antimicrobial agents. Key words: Crotalaria bernieri, antimicrobial activity, disc diffusion method, microdilution method, minimum inhibitory concentration, minimum bactericidal concentration, minimum fungicidal concentration.

Two clerodane diterpenoids, antadiosbulbins A and B and two 19-norclerodane diterpenes, 8-epidiosbulbins E and G along with the known diosbulbin E as well as nine known phenolics including five phenanthrenes and stilbenes and four flavonoids were isolated from the ethyl acetate soluble part of the methanolic extract of the tubers of Dioscorea antaly, a yam endemic to Madagascar. Structures were determined by analysis of the spectral data, mainly 2D-NMR and mass spectrometry.

International audience; A new species of Dioscorea from Morondava prefecture in Western Madagascar is described. Dioscorea bako Wilkin differs from D. alatipes Burkill & H. Perr. by its usually shallowly and irregularly lobed leaf margins, broader leaf blade (grey-green below), longer petiole and the broadly cuneate area where the petiole is inserted onto the leaf blade in the basal sinus. It is pubescent, especially densely on young shoots and inflorescences. It is endemic to Morondava Préfecture and is endangered under IUCN Red List category criteria (IUCN 2001). The unusual morphological features of its inflorescences, some of which are shared with D. alatipes are discussed. Dioscorea bako is a favoured food source for people of the Menabe region and is reported by them to be increasingly hard to find. Immediate conservation measures are necessary to ensure that it remains extant and, in the medium to long term, research should be undertaken to guide its sustainable utilisation.

In this study, we report for the first time the presence of alkaloids belonging to β-carboline type in the pods of the endemic Albizia polyphylla from Madagascar. Three major alkaloids were isolated and structurally identified as: 1-methyl-β-carboline, (+)-(R)-1-methyl-1,2,3,4-tetrahydro-β-carboline and (–)-(S)-1,2-dimethyl-1,2,3,4-tetrahydro-β-carboline.

International audience; The leaves of Dilobeia thouarsii (Roemer and Schulte), a tree that is endemic to Madagascar (Proteaceae), are used in traditional Malagasy medicine to treat bacterial skin infections and wounds. This study investigated the in vitro antibacterial activities of D. thouarsii leaf extracts and identified the bioactive compounds with the aim of providing a scientific basis for its use against skin diseases. Using broth microdilution method for leaf crude extract and its compounds, we investigated inhibition of the growth of Bacillus cereus, Bacillus megaterium, Staphylococcus aureus, Enterococcus faecalis, Vibrio harveyi, Vibrio fisheri, Salmonella Typhimurium, Salmonella antarctica, Escherichia coli, and Klebsiella pneumoniae. The two purified phenolic compounds from leaf ethyl acetate extracts (1, 2) were found to be more active than the crude extract itself. The structure of the two compounds was elucidated by NMR and mass spectrometry: compound 1 was identified as 4-aminophenol and compound 2 as 4-hydroxybenzaldehyde. A marked inhibitory effect (MIC 1 mg/ml). To conclude, the high antimicrobial activity of D. thouarsii leaf extracts against S. aureus supports its traditional use to treat skin infections.

International audience; The study of the EtOAc extract of the leaves of Dilobeia thouarsii led to the isolation and identification of seven new diprenylated dihydroxyflavonols named dilobenol A–G (1–7). Their structures were elucidated by spectroscopic analysis including UV, IR, 1D and 2D NMR and MS as well as by chemical hydrolysis. The isolated compounds were assessed for their antibacterial, antiplasmodial and cytotoxic activities. They exhibited moderate growth inhibitory activities against Staphylococcus aureus, Vibrio spp., Bacillus spp, and Plasmodium falciparum without significant toxicity against mammalian cell line L-6.

The physical need or status‐quo approaches have not provided the appropriate conceptual framework for guiding food aid policies. As a response to this, models based on household or individual behavior are being articulated to explain food vulnerability. However, due to the complexity of these models and their data requirements, they have yet to become operational for the determination of food needs. This paper proposes a simple alternative approach for estimating food needs by implicitly taking into account the income distribution patterns, levels of poverty and market structure in a society. This new method, termed the “social need” approach, is illustrated using a case study from Madagascar. During the last decade domestic availability of major nutrients in the country remained above the total per capita caloric need (physical requirements) of the population. Nevertheless, the country experienced a major food crisis in 1982 and 1983. Because of relatively stable economic, social and political inequality...

Rhodocodon madagascariensis, also named Urginea mascarenensis, is a malagasy plant belonging to the Hyacinthaceae family. As for the other members of the endemic malagasy genus Rhodocodon, the chemical and toxicological properties of this species have not yet been studied. The present study concerns the analysis of the toxicity of R. madagascariensis to medaka embryo-larval development. The incubation of medaka fish embryos or larvae in a medium containing R. madagascariensis extract resulted in a dose dependent reduction in development of embryos leading to lethality and a drastic reduction in survival rate of exposed larvae. Survival rates were reduced up to 100% with an extract concentration of 4 mg mL(-1). The LD(50) was estimated to be 1 mg mL(-1). Anatomopathological studies did show some neuro-embryonal modifications in the encephalic region. The data presented in this paper thus extends the use of medaka embryos as a valuable model to detect and analyse the effects of plant toxins.

The yams edible starchy tubers, are of cultural, economic and nutritional importance in tropical and subtropical regions. The present study concerns the analysis at different levels of Dioscorea antaly toxicity to medaka embryo-larval development. The incubation of medaka fish embryos in a medium containing Dioscorea antaly extract resulted in a dose dependent reduction in survival rate. Survival rates were reduced up to 100% with extract concentrations of 4 mg mL −1 . The LD 50 was estimated to be 0.86 mg mL −1 Dioscorea antaly. Anatomopathological studies did not show any caustic effects, irritation to mouth, throat or intestinal tract in surviving embryos but rather an inflammatory reaction in the liver. The data presented in this paper thus extends the use of medaka embryos as a valuable model to analyze the effects of food toxins.

Investigations on the phytotoxicity of Albizia species were conducted under laboratory conditions in order to assess their possible use in the control of weeds and invasive plants. The effects of seed methanolic extracts obtained from A. androyensis, A. bernieri, A. divaricata, A. greveana, A. masikororum and A. viridis, all endemic of Madagascar were evaluated against seed germination and early seedling development of vegetables (Phaseolus vulgaris, Pisum sativum, Petroselinum crispum, Brassica sp., Cucumis sp., Allium cepa, Zea mays and Oryza sativa). The effects of these extracts on seed germination of weeds (Eragrostis pilosa, and Panicum subalbidum) and invasive plants (Acacia dealbata, Cassia rotundifolia and Pinus kesyia) were also studied. Globally, all the extracts (1 mg/mL) inhibited the seed germination of all the test plants. However, the inhibitory effect varied according to both the Albizia extract and the target plants. Inhibition rates could reach 100%. The extracts (0.45 to 7 mg/mL) also significantly (p

Glabrin, the toxic principle of Cnestis glabra isolated from root bark, was identified as S-(3-amino-3-carboxypropyl)-S-methyl sulphoximine (methionine sulphoximine) by spectroscopic and chemical means. The natural occurrence of this toxic methionine derivative is reported for the first time.

ObjectivesTo define characteristics of Klebsiella pneumoniae isolated from carriage and infections in mothers and their neonates belonging to a paediatric cohort in Madagascar.MethodsA total of 2000 mothers and their 2001 neonates were included. For each mother, vaginal and stool samples were collected at the birth. Additionally, upon suspicion of infection, samples were collected from suspected infected body sites in 121 neonates. Genomic sequences of all isolated K. pneumoniae were used for phylogenetic analyses and to investigate the genomic content of antimicrobial resistance genes, virulence genes and plasmid replicon types.ResultsFive percent (n = 101) of mothers were K. pneumoniae positive. Of 251 collected K. pneumoniae isolates, 102 (40.6%) were from mothers and 149 (59.3%) were from neonates. A total of 49 (19.5%; all from infants except 1) isolates were from infected body sites. MLST identified 108 different STs distributed over the six K. pneumoniae phylogroups Kp1 to Kp6. We found 65 (25.8%) ESBL producers and a total of 101 (40.2%) MDR isolates. The most common ESBL gene was blaCTX-M-15 (in 99.3% of isolates expressing ESBL). One isolate co-harboured blaCTX-M-15 and blaNDM-1 genes. Three isolates from infected body sites belonged to hypervirulent-associated ST23 (n = 1) and ST25 (n = 2). We observed two cases of mother-to-child transmission and sustained K. pneumoniae carriage was identified in 10 neonates, with identical isolates observed longitudinally over the course of 18 to 115 days.ConclusionsThis study revealed substantial genetic diversity and a high rate of antimicrobial resistance among K. pneumoniae isolated from both carriage and infections in Madagascar.