Background: Essential oils are liquid extracts from aromatic plants, which have numerous applications in multiple industries. There are a variety of methods used for the extraction of essential oils, with each method exhibiting certain advantages and determining the biological and physicochemical properties of the extacted oils. Essential oils from different plant species contain more than 200 constituents which are comprised of volatile and non-volatile components. The application of essential oils as antimicrobial, anticancer, anti-inflammatory and anti-viral agents are due to their effective and efficient properties, inter alia. Methods: Several advanced (supercritical fluid extraction, subcritical extraction liquid, solvent free microwave extraction) and conventional (hydrodistillation, steam distillation, hydrodiffusion, solvent extraction) methods have been discussed for the extraction of essential oils. Advanced methods are considered as the most promising extraction techniques due to less extraction time, low energy consumption, low solvent used and less carbon dioxide emission. Conclusion: This manuscript reviewed the major research studies in the field and discussed several research findings on the chemical composition of essential oils, methods of oil extraction, and application of these oils in pharmaceutical and therapeutic fields. These essential oils can be used as anticancer, antimicrobial, antiviral, and as skin permeation enhancer agents.

Technology and environmental innovations always have a growing emphasis and have affected various industries. Since the cosmetics industry is highly competitive and consumers always desire innovations in products, the cosmetics industry tends to launch new products to satisfy customer desires without exception. Recently, in the area of cosmeceuticals, the application of nanotechnology has been attempting to increase; however, it seems to be tackling certain disadvantages compared to traditional products. Cosmeceuticals based on nanotechnology offer the benefits of product differentiation, improved bioavailability, and prolonged effects of active ingredients. These are widely used as a regulated delivery medium for cosmeceuticals, such as shampoo, nail enamels, lotions, hair serums, and conditioners. Their wide application is attributed to their intrinsic properties, such as rapid penetration, stability, hydrating power, and texture. The ability of the nanoemulsion system to form small- and large-surface nanoparticles enable the bioactive components to be transported into the skin more effectively. Furthermore, natural cosmetics are a general term that refers to all preparations for external conditioning and beautifying of the body from ingredients produced by or found in nature. The purpose of this review is to understand the nature of natural cosmetics which incorporate nanotechnology for better encapsulation and a better drug delivery system. The importance of innovations in the cosmetic industry is also discussed.