KASARGOD, India — In India, the world’s largest producer and shopper of betel nut, recognized regionally as areca, the fruit has lengthy been chewed and used for spiritual and cultural ceremonies. But curiosity in using the nuts to supply highly effective, environmentally sound cloth dyes is starting to develop.

The juice of the nuts, the fruit of the palm tree Areca catechu, which is frequent all through the Asia-Pacific area, has lengthy been recognized to stain chewers’ enamel and locations the place they spit. However, it has additionally been used for years on a small scale as a base for dyes in Taiwan, Malaysia, Indonesia, Myanmar and Bhutan, in addition to India.