Background In this study, 13 different extracts were investigated which are grown in the region of Erzurum. Objective The aim of this study was to screen various plant extracts that are known and used for medicinal purposes such as Ferula communis L., Rumex patientia L., Gundelia tournefortii L., Rheum ribes L., Asphodeline taurica, Polygonum arenastrum, Allium schoenoprasum L., and Ferula orientalis L. Materials and methods Medicinal parts of plants such as leaves, flowers, and stems were investigated by 2,2-diphenyl-1-picrylhydrazyl, ferric reducing antioxidant power, and cupric reducing antioxidant capacity assays: Centaury and Blackthorn. Total phenolic content, total flavonoid content, and antimicrobial properties were also determined. Antibacterial and antifungal activities were investigated by the microdilution method and the agar diffusion method respectively. Results Accordingly, the results of the Rheum ribes L. plant have the highest antioxidant activity among all analyses made. But in almost all antioxidant analysis methods, the lowest antioxidant activity was found in Ferula orientalis L. According to the antibacterial analysis applied, it was found that the plant extracts were generally more effective on yeast strains than the test bacteria used; that is, most of the plants have antifungal effect. Conclusions Due to their antimicrobial, antifungal, and antioxidant properties, the extracts of these plants might be used as natural sources in the pharmaceutical and cosmetic industries.