Limonene

Biology

High-performance liquid chromatography

Chromatography

Gas chromatography–mass spectrometry

Essential oil

Botany

Food science

Sabinene

Organic chemistry

Apiaceae

Antioxidant

Gas chromatography

Thymol

Mass spectrometry

Chemistry

DPPH

Industrial Crops and Products

Aromatic and medicinal plants, such as those from the Apiaceae family, and their metabolites, namely essential oils are of great industrial interest and a source of biologically relevant compounds. Essential oils are the major resource obtained during the hydrodistillation of aromatic plants, however, this process also originates high amounts of residual water. Although this by-product is discarded, it is conceivable that this water may be rich in non-volatile compounds which possess interesting biological properties. Therefore, the aim of this work is to analyze the oil and the hydrodistillation residual water of Crithmum maritimum L. (sea fennel), a highly aromatic plant widely used in many European countries and highlight the bioactive potential of both products. High performance liquid chromatography-photodiode array detector-mass spectrometry (HPLC-DAD-MS/MS) analysis of the hydrodistillation residual water showed a profile rich in hydroxycinnamic acids and small amounts of flavone and flavonol glycosides. Chemical analysis of the essential oil by gas chromatography coupled with mass spectrometry (GC-–MS) has revealed that γ-terpinene (33.6 %), sabinene (32.0 %) and thymol methyl ether (15.7 %) are the major compounds. The antioxidant potential of the residual water was disclosed by the 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay and a composition-activity relationship was unveiled by thin layer chromatography (TLC). The anti-inflammatory potential was demonstrated by using an in vitro model of inflammation (lipopolysaccharide (LPS)-stimulated macrophages). Furthermore, the antifungal potential was evaluated by the capacity to inhibit two important virulence factors in Candida albicans. Our results show that the residual water have a promising antioxidant potential as measured by DPPH scavenging assay (IC50 of 650 ± 160 μg/mL). Chlorogenic acid and quercetin derivatives found in the hydrodistillation residual water are the mainly contributors for this activity. The essential oil of C. maritimum (3.125 μg/mL) decreases the production of nitric oxide in LPS-stimulated macrophages by 37 % without affecting cell viability. In addition, the essential oil has a strong effect on virulence factors of C. albicans through inhibiting the formation of the germ tube by more than 50 % at 30 μg/mL besides, it is able to inhibit biofilm formation by decreasing both the biomass and the cell viability. Summing up, the present work highlights that the essential oil of Crithmum maritimum and the non-volatile extract rich in hydroxycinnamic acids and flavonoid glycosides, obtained after the hydrodistillation process have important biological activities, thus endorsing the industrial exploitation of this plant.

Chemical composition of Crithmum maritimum L. essential oil and hydrodistillation residual water by GC-MS and HPLC-DAD-MS/MS, and their biological activities