Weeds as ethnomedicine: Revisiting Kerala’s ten indigenous plants called Dasapushpam

Indigenous medicine consists of medicinal information about herbs which evolved through generations among various communities prior to the advances in modern medicine. Many of these plants are now considered as weeds as they grow near waysides, agricultural and wastelands. Weeds are considered obnoxious because of their negative effects on agricultural ecosystems. However many of them like the Dasapushpam (from Sanskrit dasa, meaning ‘ten’, and pushpam, meaning ‘flower’), or the ten sacred flowers, are ten herbs which are culturally special to people belonging to the state of Kerala, India. These herbs usually grow in the Western Ghats region. Many medicinal properties have been attributed to these plants which grow as weeds and are used in traditional medical practices of Ayurveda, Unani and Siddha. The plants which are called collectively as Dasapushpam are Aerva lanata, Biophytum sensitivum, Cardiospermum halicacabum, Curculiogo orchioides, Cynodon dactylon, Eclipta alba, Emilia sonchifolia, Evolvus alsinoides, Ipomoea sepiaria and Vernonia cinerea. Several studies have been carried out on the individual plants as well as some plants together. This classical review aims to document the botanical nomenclatural systematics, indigenous uses and published information with respect to the phytochemical, pharmacological, and therapeutic properties of the plants belonging to Dasapushpam group. However, actual utilisation of all these plants is limited and there is a need to explore all its health benefits. These groups of plants which were common in Kerala are now difficult to find due to shrinkage of agricultural land, consideration as weeds and modernisation of home spaces. Therefore, in this review, we intended to give an up-to-date knowledge on the different bioactive metabolites from the Dasapushpam group of plants, their health-related applications, and their scope for commercial applications in herbal pharmaceutical industries.