Screening of medicinal insects from Burkina Faso with potential antibacterial activity against pathogenic Gram-positive bacteria

Background Insects and their products are used to treat various pathologies, particularly in traditional medicine. This treatment is performed empirically. Currently, the antibiotic resistance of pathogenic microorganisms is growing exponentially. To deal with this situation, it is essential to find other sources of bioactive molecules. The objective of this study was to evaluate the antibacterial activity of aqueous extracts of medicinal insects against Gram-positive pathogenic bacteria. A total of thirteen aqueous extracts of medicinal insects at different stages of development were tested on seven Gram-positive pathogenic strains. Antibacterial activity of insect extracts was tested using the sol inhibition diameter medium diffusion method. Imipenem was used as the reference antibiotic. The inhibition was revealed by the appearance of clear rings around the discs. XLSTAT 2019 and R 4.2.1 software were used for data analysis. Results Extraction yields varied from one insect to another. All aqueous insect extracts exhibited inhibitory activity against the different pathogenic strains tested. Inhibition diameters varied from one bacterial strain to another and from one extract to another. The largest inhibition diameter reported was 22.5±0.5mm with Acheta domesticus extract against Enterococcus faecalis ATCC 29212. The lowest diameter of 8.5±0.5mm against Clostridium sporogenes MAR03 19404 has been reported with Cirina butyrospermi extract. All of these bacterial were susceptible to imipenem. The highest bacterial multidrug resistance index was 0.69, reported with Staphylococcus saprophyticus 652615, and the lowest was 0.23, reported with Clostridium perfringens ATCC 13124. Conclusion This study revealed the antibacterial activity of insect extracts used by traditional health practitioners to treat their patients. Entomotherapeutic could be an alternative for treating bacterial pathologies, particularly those related to multi-resistant Gram-positive bacteria.