Saponin: Properties, Methods of Evaluation and Applications

Saponins are secondary metabolites with high molecular weight. They present in a wide range of plant species and are distributed throughout the bark, leaves, stems, roots and even flowers. Saponins are bitter in taste and in recent years, they have received considerable attention because of their various biological activities including hepatoprotective, anti-ulcer, anti-tumor, antimicrobial, adjuvant and anti-inflammatory activities. Saponins are composed of a lipid soluble aglycone consisting of either a sterol or more commonly a triterpenoid and water soluble sugar residues, due to their amphiphilic nature, they are highly surface active and their biological activities are related to their chemical structures. Both steroidal and triterpenoids saponins show detergent properties. The aim of the present article is to review the saponin and methods of evaluation and also, their application based on the recent studies.