Biological Activities of Essential Oils

Essential Oils (natural mixtures of single fragrance compounds) do possess biological properties. Besides psychological influences, these rather small and lipophilic molecules exhibit distinct physiological activities upon inhalation and/or topical administration which can be shown in animal experiments as well as in human studies. After a short introduction about the correct definition of the term „Essential Oils“ new research results on the application of fragrance compounds in therapy are presented. Examples of the biological properties of these natural compounds will be discussed and a great bow drawn from the effects on the human autonomic and central nervous system to „other effects“. These cover e.g. anti-inflammatory activities, anti-oxidative ones and penetration enhancing properties, anti-microbial and insect repellent activities and the possibility to use these small molecules in cancer prevention or therapy and against Alzheimer's disease. Some studies on the biochemical mechanism of such effects are also presented as well as methods to investigate the above activities of essential oils.