Screening for phenolic acids in five species ofIriscollected in Mongolia

Summary Five species of Iris commonly used in Mongolian traditional medicine (Iris dichotoma Pall., Iris flavissima Pall., Iris bungei Maxim., Iris lactea Pall., and Iris tenuifolia Pall.) were analyzed for the presence of phenolic acids. This was the first study of the phenolic acid content of these species. Samples containing the phenolic acids were prepared by the method of Świcatek and then analysed by HPLC with UV-visible diodearray detection (DAD). Identification was performed by comparing retention times with those of standards. Quantitative determination was performed at the absorbance maximum of each phenolic acid (320 nm for ferulic, p-coumaric, and caffeic acids, 280 nm for trans-cinnamic, syringic, and gallic acids, and 254 nm for vanillic, m-hydroxybenzoic, p-hydroxybenzoic, and protocatechuic acids). As the result of our study ten phenolic acids, both free and liberated by alkaline and acid hydrolysis, were identified by HPLC. Chromatographic investigation revealed the presence of vanillic acid, protocatechuic acid, trans-cinnamic acid, p-hydroxybenzoic acid, p-coumaric acid, ferulic acid, gallic acid, syringic acid, m-hydroxybenzoic acid, and caffeic acid. Quantitative analysis of these acids was also performed. Finally, the presence or absence of some phenolic acids after alkaline or acid hydrolysis was also observed.