Evaluation of Susceptibility and Resistance of Human Infectious Bacteria and Identification of Bioactive Compounds in Pistacia atlantica, Cassia absus, and Quercus persica

Background: The antimicrobial activity of plants has long been considered an effective mechanism for controlling pathogenic microorganisms. Objectives: This study aimed to identify phytochemical compounds of the seed extracts from ethnomedicinal plants of Pistacia atlantica, Cassia absus, and Quercus persica with Gas Chromatography-Mass Spectrometry (GC-MS) and investigation of their antibacterial and antioxidant activities. Methods: The seeds were collected from Lorestan Province, Iran. Their antibacterial and antiradical activities were analyzed by disk-diffusion and 2,2-diphenyl-1-picrylhydrazyl assays, respectively. Ethanol (96%), methanol (80%), and distilled water extracts were obtained by the maceration method. The methanol extract was used for the analysis of chemical compositions. Results: About 40, 31, and 8 compounds were identified by GC-MS in the seeds of Cassia absus, Pistacia atlantica, and Quercus persica, respectively. Results indicated that 2,4-di-tertbutylphenol (36.043%) and tetradecanoic acid (4.92%) were dominated in the seed extracts of Cassia absus. However, germacyclopetene (38.119%) and 1,2,3-benzenetriol (8.115%) were dominated in the seed extracts of Pistacia atlantica. Furthermore, 5H-tetrazole-5-thione, 1,4-dihydro-1,4-dimethy (38.505%), and tetradecanoic acid (30.546%) were dominated in the seed extracts of Quercus persica. The strongest radical scavenging activity and the highest inhibitory activity against M. luteus were observed on the methanol extract of C. absus. was changed to The highest inhibitory activity against M. luteus was observed on the methanol extract of C. absus. Conclusion: Because of the presence of antimicrobial compounds in the tested ethnomedicinal plants, they can be used to synthesize new antimicrobial drugs in medicinal and pharmaceutical sciences.