Abstract

Antibiotic resistance is a serious global threat to public health. This has promoted the research for new drug targets, and the use of other approaches, such as antimicrobial combined therapy. The present study evaluated the antibacterial activity of 88 extracts from Brazilian Atlantic Forest trees. The organic extract from leaves of Miconia latecrenata (EMl) was the most promising for inhibiting the growth of Staphylococcus aureus (0.3 mg/mL) and Pseudomonas aeruginosa (2.5 mg/mL). After the bioguided fractionation of EMl and metabolite profiling performed by UPLC-DAD-MS/MS, the ethyl acetate (AFMl) and aqueous (WFMl) fractions showed a mixture of phenolic compounds derived from ellagic acid and quercetin. The MIC value of AFMl was two-times lower than EMl for P. aeruginosa, suggesting that these phenolic compounds can perform bioactivity. Furthermore, EMI and AFMl showed synergism with ampicillin and tetracycline for S. aureus and P. aeruginosa, respectively. These findings suggest that extract and fractions of the Miconia latecrenata leaves can be used as therapeutic antibacterial agents.

摘要

抗生素耐药性是对公共健康的严重全球威胁。这促进了新药物靶点的研究，以及其他方法的使用，如抗菌联合治疗。本研究评估了 88 种巴西大西洋森林树提取物的抗菌活性。Miconia Latecrenata (E M1 )叶子的有机提取物最有希望抑制金黄色葡萄球菌(0.3 mg/mL) 和铜绿假单胞菌(2.5 mg/mL)的生长。通过 UPLC-DAD-MS/MS对 E Ml进行生物引导分级分离和代谢物分析后，乙酸乙酯 (AF Ml ) 和水溶液 (WF Ml) 馏分显示来自鞣花酸和槲皮素的酚类化合物的混合物。对于铜绿假单胞菌，AF Ml的 MIC 值比 E Ml低两倍，表明这些酚类化合物可以发挥生物活性。此外，对于金黄色葡萄球菌和铜绿假单胞菌，E MI和AF M1 分别显示出与氨苄青霉素和四环素的协同作用。这些发现表明，Miconia Latecrenata叶的提取物和级分可用作治疗性抗菌剂。