ABSTRACT
Background: Many members of the genus Satureja L. [Lamiaceae] have interesting pharmacological and biological properties
Objective: In this research, major essential oil [EO] compositions, rosmarinic acid [RA] content, and antioxidant and antibacterial properties of the leaf extracts of nine Satureja species [S. bachtiarica, S. mutica, S. sahandica, S. macrantha, S. atropatana, S. edmondi, S. spicigera, S. isophylla and S. intermedia] were assessed
Methods: The chemical composition of EO was determined using Gas Chromatography [GC] and Gas Chromatography/Mass Spectrometry [GC-MS] analysis. RA content of the extract was detected using a High-Performance Thin-Layer Chromatography [HPTLC] method, and the 2,2-diphenyl-2-picrylhydracyl hydrate [DPPH] radical scavenging procedure was used to study of antioxidant capacity
Results: According to the analytical results, EO of the most samples were mainly composed of p-cymene, gamma-terpinene, thymol, and carvacrol. There was a wide variability for RA content among the studied species ranging from 0.03 mg g[-1] RA [S. sahandica] to 1.11 mg g[-1] RA [S. isophylla]. The lowest IC[50] in the radical scavenging assay was shown by S. sahandica extracts as compared to the other samples. This activity was followed by S. spicigera and S. edmondi. The minimum inhibitory concentration [MIC] varied from 0.06 to 32 mg ml[-1], however, the minimum bactericidal concentration [MBC] value differed from 0.06 to >64 mg ml[-1]. Moreover, S. sahandica revealed the lowest inhibitory activity against all microorganisms tested particularly on E. coli
Conclusion: In conclusion, the extracts of certain Satureja species have the potential to be considered as alternatives for synthetic food preservatives and antibiotics
ABSTRACT
Regarding the importance of finding new antibacterial drugs, screening of plants as a promising resource are now conducted worldwide. In this study, we report the application of a simple previously described method for screening of different plant seeds in order to find the best resources of plant antimicrobial peptides. Total water soluble protein of 10 different plant seeds were extracted and subjected to SDS-PAGE and subsequent agar-overlay bioassays. Standard strains of Staphylococcus aureus, Enterococcus faecium and Escherichia coli were included in the bioassays. This method also was used for total proteins precipitated by Ammonium sulphate which ensure the protein nature of the test substances. Molecular size and the amounts of effective peptides were estimated using Tricin-SDS-PAGE and densitometry. Two different plant seeds showed noticeable antibacterial activities against tested Gram positive bacteria and a moderate inhibitory effect on Gram negative ones. Based on the results of Tricin-SDS-PAGE analysis which were carried out in parallel to bioassays, it was concluded that effective antibacterial substances are peptides with molecular weight of slightly larger than 5 kDa. On the basis of results of agar-overlay experiments and by screening of 10 different herbal seeds, we could introduce seeds of M. sativa L. and Onobrychis sativa Lam., as great sources of putative plant antibacterial peptides. The proposed screening method can be used for screening of large number of different plant seeds and even other parts of the plant body, regarding some necessary modification in total water soluble protein extraction steps