“ Essential oil ” derived from the word “ quintessence ”. Based on Aristotelian idea, matter is composed of four elements: fire, air, earth, water; the fifth element, or quintessence , is the soul and spirit of the aromatic plants. Some even said it is the life force of the plants. Of course, nowadays, we know that, essential oils are the aromatic essences extracted (distillation, cold pressing…) from roots, flowers, fruits, herbs or trees. It is the plant’s second metabolism developed over the centuries for survival, defense against microbial pathogens, adapting to the ever-changing environment and used for attracting pollinating insect. This is why essential oils have therapeutic properties such antiseptic, anti-virus, anti-fungal, immune stimulating which is beneficial to our mankind. Essential oils are highly concentration, volatile and fat-soluble. It differs from fixed oils which contain glycerides or fatty acids which will not leave a permanent stain on fil...