Phytochemical Analysis, In-Vitro Antioxidant and Antimicrobial Activities of Flower Petals of Rosa damascena

Abstract

Rosa damascena commonly called as Rose is one of the most important plant for the pharmaceutical, flavour and fragrance industries. Rose petals extract and rose water is commonly used for skin enhancement by the cosmetics industry. The objective of the present study was to evaluate the antioxidant and antibacterial activity of aqueous and methanol extracts of Rosa damascena flower petals. Individual aqueous and methanol extract were prepared by Soxhlet extraction method. Phytochemical analysis of the extracts showed the presence of carbohydrates, proteins, tannins, phenols and alkaloids. The total phenolic content and total flavonoid content was also determined. The hydrogen donating ability of the extracts were measured in the presence of 1,1- diphenyl- 2- picryl-hydrazyl (DPPH) radical. The IC50 values of aqueous and methanol extract were 8.30μg/ml and 4.85 μg/ml respectively by DPPH method and 70.90μg/ml and 47.18μg/ml respectively by Griess assay method. The IC50 values were comparable with standard ascorbic acid. Antibacterial activity of the extracts was determined by the agar diffusion method against 9 species of bacteria and fungi: Staphylococcus aureus, Sterptococcus pyogens, Clostridium perfringens, Pseudomonas aeroginosa, Escherichia coli, Klebsiella pneumonia, Klebsiella aerogens, Candida albicans and Aspergillus niger. Both extracts were found to be effective against all the bacteria except Aspergillus niger. Methanol extract showed good antimicrobial activity at 40 mg whereas aqueous extract showed good antimicrobial activity at 80 mg when compared with standard Chloramphenicol and Fluconazole. The presence of flavanoids and phenolic compounds in the Rosa damascena flower extracts may have contributed to the antioxidant and antibacterial activities.