Dottorato in SCIENZE FARMACEUTICHE

Titolo della tesi: Interdisciplinary Advances in Essential Oil Research: Chemical Analysis, Biological Properties, and Applications

From many plants it is possible to extract mixtures of volatile organic substances, better known as essential oils (EO). Used since antiquity in a variety of fields areas such as cosmetics and food. In addition, known for their antiseptic activity, for their medicinal properties and for their fragrance, they are used as antimicrobial agents, analgesics, sedatives, anti-inflammatory spasmolytics, local anaesthetics and also as anti-cancer agents. Very important is the characterisation of the components with biological activity that are identified mainly in secondary metabolites: these molecules, although present in small concentrations, are very important as they give the plant against predatory microorganisms and insects, act as attractive pollinators and can act as chemical adaptors under conditions of stress. These substances are found in abundance in various plant families, particularly in the Asteraceae, Lauraceae, Apiaceae, Rutaceae, Liliaceae, Lamiaceae, Magnoliaceae, Cupressaceae and Pinaceae. The study carried out in recent years on EOs and hydrosols (the latter often considered as waste products) and their applications has become the subject of great interest in phytochemistry, chemotaxonomy, but increasingly in food and pharmaceuticals to combat certain pathogen species, insects and virus vectors against various crops. It is therefore necessary to carry out a thorough chemical study of the entire "essential oil complex", since there are so many components and so many synergies, both positive and negative, that have been experimentally found. Essential oils are the product of the secondary metabolism of plants and are generally volatile and fragrant, composed of a complex mixture of mono- and sesquiterpene hydrocarbons and oxygenated materials biosynthetically derived from them. The quality and quantity of EO that can be obtained from a plant can vary due to several factors: the type of plant, when it is harvested, the extraction method, etc. Production varies greatly from plant to plant depending on the variation of a few main factors, divided into intrinsic factors (phenology and ontogeny) and extrinsic factors (light, temperature, water and nutrients). Essential oils are produced industrially by steam distillation. This process influences the olfactory and organoleptic properties, so the chemical composition is certainly altered, so it is not easy to exclude the formation of artifacts. Today, the use and experimentation of EOs and hydrosols continues its path of growth and recognition in all areas of health and nutrition, in the face of increasingly resistant fungal infections, for the need to fight the same pathologies with biological weapons, with a view to finding new solutions in the nutritional and agronomic fields.