Floral Biology and Diversity

Strobilanthes cusia (Assam indigo Chinese rain bell) is a perennial shrub in the family Acanthaceae native to South and Southeast Asia including India China Indochina and Malaysia. It grows 0.5-1.8 m tall with four-angled stems ovate serrated leaves and violet to pink tubular flowers.Traditionally its leaves were a major source of natural indigo dye due to their high indican content. Besides dyeing textiles it holds importance in traditional medicine especially in Chinese herbal practice under the name Ban-Lan-Gen used for fever sore throat infections and skin disorders. In folk medicine across Asia it's applied for respiratory ailments inflammation and wound healing.Chemically it contains indole alkaloids (indigo indirubin tryptanthrin) triterpenes (lupeol betulin) and glycosides many of which show antiviral anticancer antibacterial and anti-inflammatory activity. Recent studies confirm its activity against coronaviruses and certain bacteria.Today it is valued both for sustainable natural dye production and as a source of bioactive compounds for pharmaceutical research.