A Review on Phytochemicals (Including Essential

Essential oils are aromatic hydrophobic liquids extracted commonly by hydro distillation from a diverse number of plant parts; this includes but is not limited to flowers, buds, seeds, leaves, twigs, bark, wood, fruits, receptacles and roots [1]. Specific compounds of interest can be obtained from processing plant tissue and using separation techniques. However this approach is expensive, significant amounts of plant material are needed (unfavorable for exotic plant species), and reduced yields are usually obtained. Hence, when on high demand, or the desired compound is identified and isolated, it can be synthetically manufactured. These oils often contain diverse families of compounds which convert them in complex chemical mixtures [2]. Other biochemically active groups of compounds (e.g. polyphenols, glycosides) are usually extracted directly from the plant tissue with solvents (e.g. methanol, ethanol, ethyl acetate). A particular compound or the resulting mixture of said compounds may be biosynthesized by the plant to protect it from bacteria, fungal infections or even insects. For example, essential oils have been described to possess antimicrobial, antiparasitic, antioxidant, immune modulating, and anti-inflammatory properties and hence they have been used in animal nutrition [3]. The focus of this review will only be the antimicrobial capability of different phytochemicals.