Lavender (Lavandula angustifolia) essential oil is one of the most popular and can be considered one of the best-selling essential oils for anxiety, stress and depression. International organizations such as the World Health Organization (WHO), the European Scientific Cooperative for Phytotherapy (ESCOP) or the European Medicines Agency (EMA) validate the properties of this medicinal plant, such as anxiety and stress relief [1]. Also, interest in Helichrysum L. essential oil is growing rapidly. Helichrysum L. essential oil has been shown to have anti-inflammatory properties in recent decades. In addition, several studies have shown that secondary metabolites of Helichrysum L. act as a free radical scavenger that can restore cellular redox balance and slow tumor cell growth and can be used in cancer therapy [3].
Essential oils are made up of larger aromatic and volatile compounds found naturally in all parts of the plant. Like medicines, cosmetics and food preservatives they are widely used in different countries. Today, 3,000 essential oil types are known, and there are about 300 commercial types [5]. Demand for essential oils is growing, due to their various therapeutic properties. Helichrysum L. and Levandula L. essential oils are widely used all over the world (in cosmetics, aromatherapy, perfumery, pharmacy, etc.), therefore, this natural composition of products is very important nowadays, as natural treatments are becoming more and more popular.
One of the most common ways to obtain essential oils is steam distillation or hydrodistillation. This method is used when, in the presence of a high content of essential oils in the raw material, exposure to water vapor and distillation temperature, the essential oils do not change their compositional properties. Also, steam distillation is based on the properties of essential oils (volatility, immiscibility with water) [6].
Gas chromatography of essential oil samples, one of the test methods, was chosen because selective test methods are very important for determining the composition of essential oils. Gas chromatography - mass spectrometry (GC / MS) is one of the most important methods for the determination of purity [2].
GC - MS analysis was used for Helichrysum italicum essential oil. The study showed 67 constituents in the essential oil, accounting for 99.24% of the total oil. Essential oil is characterized by the predominance of oxygen-containing sesquiterpenes and oxygen-containing monoterpenes. The main constituents of the essential oil are $\alpha$-cedrene, $\alpha$-curcumin, geranyl acetate, limonene, neroli, neryl acetate and $\alpha$-pinene [3].
GC - MS analysis was used to determine the chemical composition of lavender oil. As expected, the main components were linalool and linalyl acetate, accounting for 32.75% and 43.13% of the essential oil, respectively [4].
According to the analysis of the literature, the volatile compounds of Helichrysum italicum essential oils are based on terpenes: nerilacetate, $\alpha$-Pinene, neroli, $\beta$-caryophyllene, bisabolene, azulene, and the dominant compounds derived from Levandula angustifolia in essential oils are linalool and linalyl acetate.