Sorghum shows potential as fabric dye

Yiqi Yang may be a Cornhusker, but if his latest research is any indication, he’s also becoming a dyed-in-the-wool sorghum husker.

Yang and Chinese colleagues recently showed that sorghum plant husks – an abundant agricultural byproduct in Nebraska and elsewhere – could serve as a fade-resistant, UV-shielding dye for wool fabrics. Though sorghum is a cereal grain used for food in some countries, the United States commonly uses it for livestock feed and some biofuel production.

“If one could use it as a colorant for textiles, we’re talking about a huge demand,” said Yang, Charles Bessey Professor of biological systems engineering and of textiles, merchandising and fashion design. “This research is helping more than just the textile industry. By finding additional uses for co-products and byproducts, we’re adding value for farmers.”

Sorghum-based dyes would also produce less environmental pollution than their synthetic counterparts, the authors said.

The researchers initially investigated wool because the fabric contains negative charges that naturally attract and retain the positively charged sorghum-based dye. Though cotton’s traits make it a relatively poor candidate for the sorghum dye, Yang said silks and nylons also have the potential to dye well. The dye has also shown promise for multiple other applications, he said, from food additives and packaging to cosmetics and hair products.

Yang and researchers from Jiangnan University reported their findings in the journal ACS Sustainable Chemistry and Engineering.