Comparison of essential oil composition and phenolic acid content of selected Salvia species measured by GC–MS and HPLC methods

Abstract

Salvia is an important genus containing nearly 1000 species of the Labiatae family; most species of Salvia are traditional herbal medicines and industrial materials with various active components. Salvia is also evidently rich in essential oils and phenolic acids. This study aimed to investigate the chemical composition of the essential oils and the content of phenolic acids in four Salvia species cultivated in Yangling, PR China. The essential oils from the fresh leaves and flowers of Salvia miltiorrhiza, Salvia przewalskii, Salvia officinalis, and Salvia deserta were obtained by simultaneous distillation extraction and evaluated by GC–MS; the phenolic acids were analyzed by HPLC. Essential oil derived from S. deserta flowers contained at most 72 compounds, while 11 compounds were common to all Salvia oils. Aromadendrene oxide-(1) (8.3%) and β-caryophyllene (11.05%) were the major constituents in essential oils from S. miltiorrhiza leaves and flowers, respectively. The limonene content in leaf oil markedly differed from that of flower oil from S. przewalskii; thujone was the predominant component in both the leaf and flower oils of S. officinalis. Moreover, β-phellandrene (29.74%) was the most abundant compound in the essential oil of S. deserta flowers. Composition of essential oils from these Salvia species showed strong tissue and organ specificity. Furthermore, the contents of ferulic acid, caffeic acid and rosmarinic acid in the aerial parts of these species were also investigated. The leaves of S. przewalskii and flowers of S. officinalis were rich in rosmarinic acid, with contents of 64.1±3.9 and 53.4±2.9mg/g dry weight, respectively. Thus, S. przewalskii leaves could be considered a good source of rosmarinic acid.