Oil-bearing roses are economically important for the perfumery and cosmetic industries; however, their performance under coastal conditions remains insufficiently characterized. This study evaluated flower yield, essential oil content, and volatile composition of four genotypes (Rosa damascena, R. alba, R. alba 'Semiplena', and R. centifolia) grown over two consecutive years under coastal conditions in Yalova, T & uuml;rkiye. Essential oils were obtained by Clevenger hydrodistillation and analyzed by GC - MS. Significant genotypic differences were observed. Essential oil content ranged from 0.011% to 0.052%, with the highest values in R. alba and R. damascena and the lowest in R. alba 'Semiplena'. Volatile profiles revealed clear genotypic differentiation: R. alba and R. damascena were enriched in monoterpene alcohols, whereas R. centifolia and R. alba 'Semiplena' showed higher levels of phenylethyl alcohol and long-chain hydrocarbons. Multivariate analyses confirmed genotype as the primary determinant, with year and harvest period as secondary factors. Coastal conditions supported satisfactory yield and oil quality.
The essential oil of Cannabis sativa L. is a valuable product with applications in medicine, cosmetics, and biopesticides. This study evaluated the effects of growth stage on essential oil yield and composition in four hemp cultivars, including two non-native monoecious types (Fedora 17 and Fed17-2) and two native dioecious types (Fars and Yazd). Samples were collected at vegetative, flowering, and seed-setting stages, and essential oils were analyzed by GC and GC/MS. Both cultivar and growth stage significantly affected oil yield. The highest yield (0.87%) was obtained from Fed17-2, while the lowest (0.54%) was recorded in Fedora 17. Essential oil content generally increased with plant maturity. Monoterpenes ranged from 7.9-50.9% and sesquiterpenes from 46.6-86.6%. Major compounds included alpha-pinene, beta-pinene, 1,8-cineole, E-caryophyllene, and alpha-humulene. Certain sesquiterpenes showed cultivar-specific patterns, particularly in native versus foreign cultivars.
The present study aimed to evaluate the antibacterial potential of commercial Syzygium aromaticum, Cymbopogon citratus and Allium sativum essential oils both individually and in combination for a gargle formulation. First, GC/MS analyses were used to verify the chemical composition of the tested essential oils. For the antibacterial activity evaluation, in vitro broth microdilution, as well as the checkerboard method, and the inhibition zones of the formulated gargles were evaluated using the disc diffusion assay. The main components were verified as eugenol (78.4%) in S. aromaticum; methyl thiirane (52.3%) in A. sativum; followed by geranial (45.4%) in C. citratus, respectively. Synergistic effects were observed for combinations with S. aromaticum and C. citratus (FICI = 0.375), also for S. aromaticum and A. sativum (FICI = 0.265and FICI = 0.375). The essential oil combinations showed in vitro synergistic and additive interactions, and the formulated gargles showed inhibition zones. These initial findings highlight the potential of essential oil combinations as natural antibacterial agents.
