ISSN 2320-5407 International Journal of Advanced Research (2015), Volume 3, Issue 12, 1559 – 1567 1559 Journal homepage: http://www.journalijar.com INTERNATIONAL JOURNAL OF ADVANCED RESEARCH REVIEW ARTICLE In vitro production of spilanthol from Spilanthes acmella Murr.: State of the art and future prospect Mithilesh Singh 1 * and Shailendra Pradhan 2 1. G.B. Pant Institute of Himalayan Environment and Development, Sikkim Unit, Pangthang, Gangtok, Sikkim- 737101, India; 2. Department of Dravyaguna, Uttarakhand Ayurved University, Gurukul Campus, Haridwar, Uttarakhand-249404, India Manuscript Info Abstract Manuscript History: Received: 14 October 2015 Final Accepted: 25 November 2015 Published Online: December 2015 Key words: Akarkara, In vitro , Medicinal plant, Secondary Metabolites, Toothache plant *Corresponding Author Mithilesh Singh Spilanthes acmella Murr., commonly known as toothache plant, is a well- known traditional plant of India. It has been demonstrated for a wide array of biological activities such as antifungal, antipyretic, bio-insecticide, antioxidant, aphrodisiac, analgesic, pancreatic lipase inhibitor, antimicrobial, diuretic, vasorelaxant and anti-inflammatory effects. These attributes are mainly due to the presence of an alkylamide, spilanthol. With increase in awareness about spilanthol therapeutic properties, industrial demand for this compound has also increased. Currently, spilanthol based industrial products are produced by collecting field grown plants. The utilization of huge quantities of whole plant parts is alarming as it can reduce local plant populations and erode genetic diversity. Moreover, the plants growing in wild undergo various climatic and environmental fluxes that may lead to change in their chemical profile. In vitro cultures have been viewed as promising alternatives to whole plant extraction for obtaining spilanthol, irrespective of seasons and regions, offering stable and consistent production. However, the research on in vitro spilanthol production is in its infancy and requires culture and process optimization for the development of a commercially feasible process. This review states the present status and future challenges of plant tissue culture for spilanthol production. Copy Right, IJAR, 2015,. All rights reserved INTRODUCTION Spilanthes acmella Murr. (Common names: Akarkara and Toothache plant) is an indigenous species that belongs to daisy family, Asteraceae. Five species of Spilanthes viz. S. acmella Murr., S. acmella L. var oleraceae clarke, S. calva L., S. paniculata L. and S. mauritiana L. are reported from India (Anonymous, 1989). Among these Spilanthes species, S. acmella Murr. and S. acmella L. var oleraceae Clarke are rare in occurrence. It is grown as perennial plant throughout the tropics and subtropics, and can be found in damp pastures, at swamp margins, on rocks near the sea and as a weed of roadsides. Spilanthes is a hairy herb upto 30-60 cm tall, with numerous prostrate or ascending branched cylindrical hairy stem and simple ovate opposite leaves without stipules.The flowers are yellow, non- fragrant with five petals on long glabrous peduncles. Many small, bright yellow colour flowers are aggregated into capitulum (flower head) which make them attractive to insects, thus, paving the way for entomophily. The plant is conventionally propagated through seeds that lose their viability within a short period of time and show slow germination rates (Pati et al., 2006; Dobránszki and da Silva, 2010). Vegetative means too have not shown successful results in propagating Spilanthes (Tiwari et al., 2011).