Different extraction methods for phenolic and volatile compounds recovery from Elsholtzia ciliata fresh and dried herbal materials

The aim of this study was to determine main chemical compounds in Elsholtzia ciliata and increase the efficiency of their extraction from herbal materials. To our knowledge, this is the first research comparing different extraction methods and conditions of the E. ciliata extracts production. Extracts were obtained by ultrasound assisted (UAE), heat-reflux (HRE), continuous stirring (CSE), maceration (ME), percolation (PE), and ultrasound assisted with percolation (UAE with PE) extraction methods In this study, 13 phenolic compounds were determined for the first time in E. ciliata extracts (quinic acid, neochlorogenic acid, chlorogenic acid, p-coumaric acid, vitexin, ferulic acid, luteolin-7-rutinoside, luteolin-7-glucoside, procyanidin B, apigenin-7-glucoside, naringenin, diosmetin, and chrysin) and six volatile compounds in essential oil (EO) (ethylfuran, shisofuran, methyl nerate, 4-vinyl guaiacol, cis-alpha-bergamotene and phytone). The lowest contents of polyphenols and ketones were obtained by PE. The optimal method for the chemical compounds recovery was UAE with the solvent 70% ethanol and 30 min extraction time. For the first time was investigated E. ciliata EO emulsion relaxation effect of rat mesenteric blood vessels. Emulsion showed a weak vasorelaxing ability.