Atividade antibacteriana de Azadirachta indica A. Juss. (Meliaceae) contra pseudomonas aeruginosa: uma revisão de escopo

Abstract

Pseudomonas aeruginosa, the main cause of nosocomial and opportunistic infections, is under continuous selection pressure. The development of antibiotic resistance increases mortality, costs, and length of hospital stay. Among searches for new antimicrobials, drugs of natural origin have been gaining more attention. Among the plants, Azadirachta indica stands out, with wide medicinal use. Due to the high potential of the substances of this plant, the importance of this research is recognized. The review method was developed and described according to PRISMA guidelines. Databases were searched (Embase, Scopus, PubMed and Web of Science), using the scientific name of the plant and the microorganism (Azadirachta indica) and (Pseudomonas aeruginosa) as Boolean descriptors and operators. The search for titles showed 368 articles in the initial screening, and of these, 13.31% (49) of the complete original articles were included. A total of 49 articles produced 73 extracts, emphasizing that the largest number of extracts were: 25 (34.24%) ethanolic from the leaves, 17 (23.28%) methanolic from the leaves and 13 (17.80%) aqueous of the leaves. In 2 (4.1%) articles, the components of the extracts were characterized by Gas Chromatography Coupled to Mass Spectrophotometry GC/MS. The lack of standardization of methodologies points to limitations in the comparison of the results of the antibacterial activity of the extracts. Due to this, the interpretation of the results and data made available in the articles and the MIC values were performed for qualitative and quantitative determination of the results, respectively. Most extracts (33=45.20%) demonstrating a medium/intermediate zone of inhibition, 8 (10.96%) demonstrated very low activity, 16 (21.92%) extracts did not demonstrate activity under all tested concentrations and in 16 (21.92%) extracts showed high inhibition results above antibiotics, with ethanolic leaf extracts being the most active (9 = 56.25%). Most of all evaluated extracts (49=67.12%) showed satisfactory results (combination of extracts with high + medium result), with ethanol extracts from the leaves representing 38.77% (19) of the 49 satisfactory extracts. Extracts from Mehrotra et al. (2010) and Samy et al. (2013) showed the best results in inhibition halo (50μL of 0.002mg/mL of extract generated 15mm of inhibition halo) and MIC (0.03125 mg/mL), respectively. This review shows that the ethanolic extracts produced from the leaves of A. indica are promising in the control of P. aeruginosa when evaluated by the disc-diffusion method. Ethanol extracts from A. indica leaves were the most promising in controlling P. aeruginosa. The data from this work justify studies aimed at developing new pharmaceutical products against P. aeruginosa. However, further testing is recommended to ensure the safety and efficacy of extracts, as well as isolated compounds from A. indica.