Characterization and Chromatographic Fingerprint Analysis of Traditional Wallflower Oil

Background and objective: Wallflower oil is made from the flowers of Erysimum cheiri (L.) Crantz which is a herb rich in cardenolide compounds. Wallflower oil was traditionally indicated for analgesic, anti-inflammatory, hair tonic, and wound healing purposes. In this paper, wallflower oil was prepared based on the method cited in Persian medicine resources. Methods: To prepare the oil, 250 g dried flower was soaked in 5000 g distilled water for 20 h. Then, it was boiled for 2 h till half of the water volume evaporated. The obtained decoction was filtered and boiled in 2500 g sesame oil until all the aqueous part evaporated. The quality control tests were performed. Results: Acid, peroxide, iodine, and saponification values were determined as 0.72±0.02 (oleic acid%), 7.16±0.10 (meq/kg oil), 104.73±0.71 (g of I2/100 g oil), and 242.85±0.29 (mg KOH/g oil), respectively. HPTLC analysis revealed the presence of cardenolide compounds in wallflower oil, decoction, maceration, and flower samples. GC-FID results recognized linoleic acid (42.91%), oleic acid (41.22%), and palmitic acid (9.76%) as major fatty acids of wallflower oil. In addition, GC-MS study identified 11 volatile compounds among which, thymol (28.13%), carvacrol (21.63%), and dodecane (11.50%) were recognized as the main components. Conclusion: Thymol and carvacrol could be used for evaluation and determination of wallflower oil. On the other hand, presence of cardenolides in wallflower oil and consequent probable cardiac actions should be considered during clinical administrations. This paper recommends further in vitro and in vivo studies as well as clinical trials to evaluate the safety and efficacy of wallflower oil.