Plant saponin biosurfactants used as soap, hair cleanser, and detergent in India

The biosurfactants derived from plants are bestowed with many characteristic features such as natural abundance, renewability, sustainability, lower cost, superior stability, biocompatibility, biodegradability, low environmental and human toxicity when compared with synthetic surfactants. In addition, their manufacture does not exhaust the inadequate petroleum reservoirs, and they show a wide range of biological properties including antidermatophytic activity. The present review provides a short description of the importance of plant saponin biosurfactants, their quantification and the applications of commonly used saponin yielding Indian plants. In India, most of the saponin-containing plants belong to various families including Sapindaceae (Sapindus sp), Fabaceae (Acacia concinna, Trigonella foenum-graecum, Vigna radiata, Cicer arietinum, Albizia lebbeck), Rutaceae (Citrus sp), Malvaceae (Hibiscus rosa sinensis), Phyllanathaceae (Phyllanthus emblica), Asphodelaceae (Aloe vera), Asteraceae (Eclipta alba), Asparagaceae (Agave sp), Dioscoreaceae (Dioscorea esculenta), etc. The various plant parts including leaves, bark, stem tubers, fruits, fruit pericarp, seeds, etc., are utilized as bathing soap, washing detergent, utensil cleaner, hair cleanser, hair conditioner, shampoo, hair oil, hair dye, etc. The utilization of herbal detergent and shampoo in pre-Harappan civilization indicates the advancement in health and hygienic practices in Indian civilization. Most of the plant saponins are used for treating various skin and hair problems. They are mild and natural; they serve natural conditioner and cleaners and do not deplete natural oils from the skin and hair. Also, most plant saponins exhibit hair follicle strengthening, hair growth promotion, and hair dyeing activities. The superior emulsifying action of natural saponins makes them ideal, ecofriendly, commercial, economical laundry detergents. Further studies are envisaged on bulk raw material production, isolation and purification of saponins, and toxicological evaluation.