Steroid-saponins from fenugreek seeds: Extraction, purification and surface properties

Two techniques for extraction and purification were excersized in order to obtain a purified saponins extract from several sources (fenugreek, soybean , locust bean and sesame). The results indicate that fenugreek steroid sapo nins extract has the best surface properties and reduces the surface tensio n to 33.3 mN/m and the tetradecane-water interfacial tension from 44 mN/m t o 7.5 mN/m. The HLB value was evaluated and found to be 18. Three different types of oil (n-tetradecane, soybean oil, tricaprylin) were emulsified wit h a 6 wt% aqueous solution of saponins to give an average droplet size of 0 .7 mu m (yet stable after month). An effective synergism is seen when these emulsions were prepared with sucrose fatty acid esters as co-surfactant. F urthermore, the foaming power was evaluated.