In insects, the hemolymph is the primary site of antimicrobial effectors produced in response to infection. In this study, the antibacterial activity of hemolymph extract from immunized larvae of Oryctes owariensis and Rhynchophorus phoenicis has been evaluated. The tests were carried out on in vitro growth of six bacterial strains including three clinical isolates (Escherichia coli ATCC 25922, Bacillus subtilis, Salmonella spp.) and three strains of food origin (Escherichia coli E1, Staphylococcus aureus S1 and S2 Meti-R). Activity of the different extracts was detected by diffusion method in a gel medium and quantified by macro-dilution technique in a liquid medium. Results showed that the different extracts demonstrate strong antibacterial activity and bactericidal power. Diameters of inhibition zones varied from 19.12±2.88 mm (E. coli ATCC 25922) to 22.58±2.18 mm (S. aureus S1) for the extract from O. owariensis infected larvae. This extract was more active on Gram positive bacteria with a MIC of 12.5 mg/mL and a MBC between 25 and 50 mg/mL. The extract from R. phoenicis infected larvae was very active on all strains with inhibition zone diameters between 26.22±0.69 mm (B. subtilis) and 35.30±2, 4 mm (S. aureus S1). MIC and MBC were respectively developed at the concentrations of 3.12 mg/mL and 6.25 mg/mL on all the bacterial strains. The sensitivity of bacterial strains to these hemolymph extracts reveals the probable presence of produced antimicrobial peptides.

The consumption of salads of the fourth range (4th range) has become increasingly worrying in Abidjan (Côte d'Ivoire). This work was undertaken to determine the microbiological status of these foods during the period of domestic conservation (7°C) after opening the packaging in order to prevent the risk of intoxication from bacterial pathogens. The material and methods used for the microbiological analyses refer to the techniques of classical microbiology followed by statistical tests through R4.1.2 and excel software. The results obtained showed that the 4th range salads sold in the hypermarkets of the city of Abidjan were highly contaminated by bacterial pathogens such as S. aureus with a prevalence of 24%, E. coli O157: H7 with 16% and Salmonella spp. with 18%. On opening the packages (D0), 63.43% of the salads were unfit for consumption, 5% had an acceptable load and 31.57% were of satisfactory microbiological quality. On the third day (D3), the rate of salads unfit for consumption increased (68.43%). On the seventh day (D7), the microbiological quality was the same as on the third day. However, the Salads of the Green Oaks (SChV) and the Meli melo salads (SMe), with perforated packaging were more conducive to the growth of the pathogens studied. Domestic refrigeration does not guarantee the safety of 4th range salads after opening the packages.

Various activities taking place in urban areas lead to the emission of a number of polluting substances that have adverse effects on the environment and ecosystems and contribute to the deterioration of the quality of the air, the soil and water. The plants grown there suffer damage due to pollution, which has the effect of negatively affecting their morphological, physiological and biochemical properties. This study was conducted to evaluate the pollution of some lettuces crop sites in the city of Daloa (Côte d’Ivoire) by measuring anatomical and biochemical parameters of lettuce (Lactuca sativa). These include stomatal density and opening, relative water content, pH, ascorbic acid content, chlorophyll, and carotenoid. These parameters made it possible to calculate the lettuce Air Pollution Tolerance Index (APTI). The results showed a reduction in stomatal density and opening, as well as pH, ascorbic acid and chlorophyll content for sites 1 and 2 in downtown of Daloa compared to site 3 located, farther away from the city center. Site 1 has an average carotenoid content (31.23 mg/g) of lettuce significantly lower than that of sites 2 and 3 which is respectively 59.70 mg/g and 58.97 mg/g. Also, significant reductions of 8.25% and 9.5% in the relative water content of lettuce at site 3 compared to sites 1 and 2 were observed. The calculation of APTI revealed the relative sensitivity of lettuce in sites 1 and 2 to pollution, compared to site 3. This study shows that sites 1 and 2 have a high risk of pollution, compared to site 3 with regard to the different parameters evaluated.

Traffic roads intensification contribute to ambient air pollution of the city of Abidjan, in Ivory Coast, as other African capitals. Biomonitoring methods based on spectrals and anatomicals plants leaves characteristics are effective to assess urban environment quality. Measurements of reflectance in the visible and taking stomatal imprints have been made on leaves of Ficus polita Vahl. Leaves were collected in roads vicinity and in parks of the city of Abidjan. Measurements of reflectance allow to distinguish road environment pollution relatively to parks while stomatal density (DS) revealed leaves anatomical response to road atmosphere quality. Air pollution impact on leaves physiology was determined by Normalised Dorsiventral Asymmetry Index (NDAI) and Stress Index (SI). NDAI is higher in parks than roadsides. Besides DS increasing values are observed with distance from the road when the contrary tendency is observed with SI. These results make it possible to consider an operational approach for assessment and monitoring of urban environment quality based on radiometric index and stomatal parameter.