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Rosa damascena Mill. is one of the most important Rosa species for the flavour and fragrance industries. The high amount of residues of spent flowers after steam distillation and the potential use of their essential oils as natural antioxidants and antimicrobials lead to determine the antioxidant and antibacterial activities of fresh and spent Rosa damascena flower extracts. The total phenolic contents were 276.02±2.93mg gallic acid equivalent (GAE)/g in FF (fresh flower) extract and 248.97±2.96mg GAE/g in SF (spent flower) extract. FF and SF extracts showed 74.51±1.65 and 75.94±1.72% antiradical activities at 100ppm. The antioxidant activity of FF extract (372.26±0.96mg/g) was higher than that of SF extract (351.36± 0.84mg/g). Antibacterial activity of the extracts was determined by the agar diffusion method against 15 species of bacteria: Aeromonas hydrophila, Bacillus cereus, Enterobacter aerogenes, Enterococcus feacalis, Escherichia coli, Escherichia coli O157:H7, Klebsiella pneumoniae, Mycobacterium smegmatis, Proteus vulgaris, Pseudomonas aeruginosa, Pseudomonas fluorescens, Salmonella enteritidis, Salmonella typhimurium, Staphylococcus aureus and Yersinia enterocolitica. Statistical differences among bacteria were significant at p 0.05. Both extracts were effective against all the bacteria except E. coli O157:H7, although the FF extract was more effective than the SF extract. FF and SF extracts showed the strongest effects against S. enteritidis and M. smegmatis, respectively.

All yields, chemical compositions, free radical scavenging activities and reducing/antioxidant capacities of extracts and essential oils of Turkish oregano changed importantly depending on vegetative periods of growing season.

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In this study, fruits, fruit flesh and seeds of damask rose (Rosa damascena Mill.) and rose hip (Rosa canina L.) were assayed for the composition of fatty acids, ascorbic acid, α-tocopherol, β-carotene, and mineral elements. The content of linoleic acid in seed oil of Rosa damascena (54.18%) was found to be higher than in that of Rosa canina (48.84%). α-Tocopherol contents were found to be 7.10 μg/g and 34.20 μg/g for Rosa damascena and Rosa canina fruits, respectively. Ascorbic acid content was determined as the highest in the fruit flesh (546 mg/100 g in Rosa damascena and 2200 mg/100 g in Rosa canina), and as the lowest in the seeds of both species. Rosa damascena fruits were found to be richer in minerals such as Ca, Fe, K, Mn, Na, P, and Zn than Rosa canina fruits. The results of the present study showed that Rosa damascena fruits could be used as food and food additive equally as rose hip fruits.