| Congresso Brasileiro de Microbiologia 2023 | Resumo: 973-1 | ||||
Resumo:Terminalia catappa Linn., known as beach almond, is widely distributed in Brazil and is used in folk medicine for its benefits in teas made from its leaves, barks, and almonds. The plants contain a wealth of compounds, making them potential sources of molecules that they use themselves against phytopathogens. These compounds include alkaloids, terpenes, lignans, flavonoids, coumarins, benzenoids, quinones, xanthones, lactones, and steroids, among others. The compounds are extracted through preparations such as extracts, which can have a liquid, semi-solid, or solid consistency, and are made using appropriate solvent extraction methods. Thus, this study aimed to obtain the ethanolic extract of T. catappa L. and test its antimicrobial activity against different reference bacteria. For the extraction, 300 grams of dried leaves were collected at the State University of Piauí, located in the city of Teresina, Piauí. The leaves were crushed and soaked in 99.9% absolute ethyl alcohol for five days. Then, the extract was filtered, rotary evaporated (at 40ºC), and lyophilized to obtain the crude extract. The extract was tested against Staphylococcus aureus, Enterococcus fecalis,Bacillus subtilis, Pseudomonas aeruginosa, and Escherichia coli . In the Agar Diffusion method, concentrations based on referenced literature of 5.0, 10.0, 20.0, 30.0, 50.0, 100.0, and 200.0 (in mg/ml) were used. The positive extracts were subjected to a liquid medium antibacterial activity test, using concentrations of 120μL, 60μL, 30μL, and 15μL of the extract, which was diluted with 3 ml of Mueller-Hinton culture medium, and the microorganism was incubated for 24 hours at 35ºC in a BOD incubator. Then, 100μL were taken from each test tube and spread on Petri dishes for colony-forming unit (CFU) counting. Absorbance at 600nm was also observed using a spectrophotometer. From the results obtained by the Agar Diffusion method, the extract was able to inhibit the growth of S. aureus, B. subtilis, and E. coli, especially at concentrations of 100 mg/ml and 200 mg/ml. The investigation of the antibacterial activity further confirmed the effectiveness of T. catappa L. extract, especially against more resistant bacteria such as Staphylococcus aureus and Escherichia coli, which remain a public health problem in terms of antibiotic resistance. Thus, the ethanolic extract of T. catappa L. demonstrated antimicrobial activity against the reference bacteria, and it could be used for medicinal purposes, allowing a reduction in the use of antibiotics and their consequences.
Palavras-chave: Terminalia catappa Linn., Ethanol extract, Medicinal plant | |||||