Phytosterol: A Functional Ingredient in Food

165 Sterols are organic compounds, widely distributed in nature. Sterols are essential structural components of eukaryotic cell membranes, where they regulate membrane fluidity and permeability as well as membrane-associated metabolic processes. They occur naturally in animals, plants and fungi. Sterols of animals are called zoosterols. The most familiar type of animal sterol is cholesterol. The major sterol in yeasts is known as ergosterol. Plants have a variety of well-studied sterols, which are collectively termed as ‘phytosterols’. This term is derived from Greek word ‘phyton’ means plant and ‘stereos’ means solid (Bartnikowska, 2009). More than 250 different phytosterols and related compounds have been identified in various plant and marine materials (Brufaua et al., 2008). Phytosterols are typically plant origin and cannot be synthesized by humans. Therefore, their source in human body originates only from diet (Tasan et al., 2006). The phytosterols have several bioactive qualities with possible implications for human health (Awad and Fink, 2000). Epidemiological evidences indicate reduced incidences of various diseases in populations consuming diets rich in vegetables and fruits. The studies were directed on protective effects of minerals, trace elements and vitamins. However, health benefits of phytosterols has been focused only in recent years and attempts yielded positive correlations in terms of chronic disease risk reduction (Jones and AbuMweisb, 2009; Rafia, 2013).