Sustainability, but Make it Fashion

Startup Tinctorium wants to save the world with our jeans.

Vectors Angel
Vectors Angel
Published in
5 min readSep 9, 2019


by Sachi Koide

America’s — and the world’s? — favorite pants are sturdy, fashionable, and blue. Everyone has a favorite style (high-waisted skinny for me please) and loves how they don’t need to wash them after every wear (it’s actually better for the color to keep them out of the laundry!). But the hidden tragedy of this $66B closet-staple industry is that making blue jeans is very bad for the environment and its workers — In particular, the chemical production of turning indigo into its iconic blue dye.

Currently, 99% of the thousands of tons of synthetic dye annually manufactured relies on hazardous and carcinogenic chemicals for production. The high temperatures and explosive chemicals required create volatile and risky conditions for the industrial workers; and the poor wastewater management and coal-powered factories stream harmful carbon emissions and pollution into an already suffocating environment. Very few sustainable alternative processes exist, and currently none are scalable to meet the needs of the massive denim market.

Green Meets Blue

The biggest names in the denim industry are interested in finding a clean way to produce indigo dye. Luckily for the world, bioengineer Dr. Tammy Hsu has spent the last six years developing the solution at UC Berkeley. It’s called Tinctorium.

Tinctorium’s CSO Dr. Tammy Hsu (left) and CEO Michelle Zhu (right).

Tinctorium is a Bay Area biotech startup working to revolutionize the world of color, starting with indigo. Their mission is to produce and apply indigo in a more sustainable way, and they’re achieving this by using a technology called microbial fermentation.

“My parents have worked in textiles for a long time, and I watched them launch and grow their own denim and apparel wholesale business when we immigrated here almost 20 years ago. I never thought I’d be working in the fashion industry but felt inspired by the opportunity to bring to it new technology and new consciousness.”

The Japanese plant P. tinctoria naturally produces a chemical precursor to indigo called indican, which develops within a sugar molecule and is isolated from the rest of the plant cell in an organelle. Specific plant enzymes are responsible for creating them. As an undergraduate and throughout her PhD at UC Berkeley, Dr. Hsu figured out a way to insert these enzyme genes into bacteria, allowing them to produce indican without the need for growing the plant.

Hundreds of liters of this harmless bacteria are now able to grow in fermentation tanks and churn out indican. A second enzyme removes the protective sugar molecule and triggers the final chemical transition to indigo. The result: a 100% sustainable process to create what was once an impossibly pollutive synthetic chemical.

As they establish expertise in the dye space, Tinctorium will expand to other colors in textiles and even other applications.

The Perfect Pair

Tinctorium’s technology originated from UC Berkeley, in John Dueber’s lab where Dr. Hsu did her PhD. The idea started out as an undergraduate iGEM (International Genetically Engineered Machines) project in the lab, where the need for this application in the denim and textile space quickly became apparent. Hsu developed this idea into a scalable process and at the beginning of 2019 teamed up with Michelle Zhu to join the IndieBio accelerator program and start full-time operations on the company.

Michelle’s fiance was part of the Dueber lab during his PhD when Tammy was there. Michelle says, “I first got acquainted with Tammy when he joined 4 years ago. While we’ve hung out socially over the years, we never really considered working together until Tammy was looking for a business co-founder at the beginning of this year. Given my background in consulting and business operations, it felt like a good skill set fit.”

Michelle was the perfect match for Tammy’s technology. “My parents have worked in textiles for a long time,” she says, “and I watched them launch and grow their own denim and apparel wholesale business when we immigrated here almost 20 years ago. I never thought I’d be working in the fashion industry but felt inspired by the opportunity to bring to it new technology and new consciousness.”

CEO Michelle Zhu presenting yarn dyed with Tinctorium’s sustainable, microbially-fermented indigo dye during her pitch at the 2019 Indie Bio Demo Day.

Hsu and Zhu completed the IndiBio Accelerator program last June.

“Since joining IndieBio,” says Hsu, “we’ve moved quickly to build out the technology and penetrate the denim industry, and the journey has been a whirlwind. We’ve scaled the process from the bench scale to a 300 liter pilot scale fermenter” and in the next two years, Tinctorium will plan to be at full industry production scale.

Using their product, they’ve dyed cotton yarns using an industrial dye machine as a proof of concept and have been able to show that their indigo dyeing process can work seamlessly as a drop-in replacement in the denim supply chain. On the business side, they’ve secured LOIs from several large denim brands and put together an advisory board that includes Adriano Goldschmied, the “Godfather of Denim”; David Breslauer, the CSO of Bolt Threads; and John Dueber, a professor of bioengineering at UC Berkeley and Tammy’s thesis advisor. They are also backed by prominent angel investor Jennifer Doudna, renowned UC Berkeley biochemist and CRISPR scientist.

Tinctorium technology in action. Tinctorium blue scarf (left) and dyed cotton yarn (right) are proof-of-concept examples of what may one day be used in your jeans.

In a 2015 article, Dueber said, “We’d all like to see our indigo research lead to greener blue jeans.” It looks like they’re about to do just that.