Entomotherapy as an alternative treatment for diseases due to Gram-negative bacteria in Burkina Faso

Abstract

Insects are known for their harmful effects. However, they also benefit humans, animals, plants, and ecosystems. Its beneficial uses include entomophagy and entomotherapy. This study aimed to evaluate the antibacterial activity of insect extracts against Gram-negative bacteria. Antibacterial activities of thirteen crude extracts of medicinal insects were tested against twelve Gram-negative bacteria by diffusion on agar. Imipenem was used as an antibiotic for positive control. The thirteen extracts acted differently against certain Gram-negative bacteria. The largest inhibition diameter was for extracts of Cirina butyrospermi and Mylabris variabilis against Pseudomonas aeruginosa ATCC27853 and Salmonella enteritidis ATCC13076, respectively. The diameters of inhibition obtained using imipenem against these same bacterial strains were 13.0 ± 0.0 mm and 22 ± 1.0 mm, respectively. The lowest inhibition diameter (7.5 ± 0.0 mm) was obtained using Anopheles gambiae extract against Salmonella Typhimurium ATCC14028. Imipenem was active on all strains tested. The highest values of the index multi-resistance to insect's extracts were reported for Pseudomonas aeruginosa ATCC9027 and Serratia odorifera 652411. Overall, the results of this study confirmed the antibacterial activities of insects used by traditional health practitioners to treat different pathologies. Entomotherapy could be an alternative treatment for certain infectious pathologies caused by gram-negative bacteria.

Figure 1

Extraction yields of the insects used.

Figure 2

Antimicrobial activity of insect extracts on Salmonella enteritidis and Providentia rettgeri. B.A: Bunea alcinoe; P.sp.: Pachychondyla sp.; A.D: Acheta domesticus ; M.V : Mylabris variabilis ; IMP: Imipenem ; A.G: Anopheles gambiae; A.M : Apis mellifera ; O.T : Odontotermes sp.

Figure 3

PCA of correlation between growth inhibitor extracts and bacteria.