Quality control of Rosa × damascena flowers from Layzangan of Fars province in Iran

Background: Damask rose (DR) with the scientific name of Rosa × damascena Herrm. is a popular medicinal plant belonging to the Rosaceae family. According to the literature, DR cultivation was originally developed in the Layzangan valley, Darab region of Fars province in Iran. Objective: In this study, quality control and standardization of Layazangan DR flowers were investigated. Methods: Histological, physicochemical, and heavy metal analysis as well as the chromatographic fingerprints including GC-MS and HPLC analysis were studied. Results: According to the microscopic observations, secretory and simple trichromes in sepal, rosette crystals in ovule, and the tricolporate shape of pollen grain were found to be the major characteristics in DR flowers. The results of heavy metal analysis revealed that the amounts of zinc (82.5 ppm), copper (4.02 ppm), lead (0.11 ppm), and cadmium (not detected) were less than maximum permitted amounts. The essential oil of fresh petals was obtained by hydro-distillation and was analyzed by GC-MS method. Twenty-three components were identified representing 98.66 % of the total essential oil composition. Citronellol (41.44 %), nonadecane (16.44 %), and heneicosane (10.58 %) were the main components. According to HPLC analysis results, quercetin was determined as 7300.5 μg/g dried DR petals. Conclusion: The essential oil obtained from Layzangan DR is rich in citronellol compound. On the other hand, the diagnostic characteristics presented in this study can help in better quality control and standardization of DR samples. It could also provide information for the authentication of relevant undeclared samples as well as the detection of adulterated materials.