The Science of Perfume

Valero Doval

Synthetic biologists are revolutionizing the perfume industry thanks to genetically engineered yeast.

Coco Chanel once said, “A woman who doesn’t wear perfume has no future.” Now you can wear the future in your perfume. Walk into the Lexington, Kentucky, labs of Allylix and you’ll see why. The first thing you’ll notice is the smell of freshly baked bread. At the center of the biotechnology company’s facility is a polished-steel cylinder bubbling with sugar, water and the same yeast you might put in dough. This is the company’s fer­menter, and if you go down the hall, the scents change—first the aroma of oranges, then tart grapefruits and, in another lab, the smoky scent of sandalwood.

When we spray perfumes and colognes onto our skin, we often picture the natural sources of these scents. Surprisingly, the smells at Allylix—nootkatone and valencene evocative of citrus groves and sandalwood evocative of Hindu temples—come from the microbe responsible for beer, wine and bread. The company has inserted genes from these natural sources into yeast to replicate their scents.

Allylix is one of a handful of companies using biotechnology to retool yeast for the flavor and fragrance industries. Scientific advances are providing a new way to produce natural ingredients cheaply without relying on harvests that are susceptible to weather or crop diseases. They also produce the ingredients­ in far higher volumes. Only ten pounds of nootkatone can be extracted from a ton of grapefruit oil, but an equivalent amount of yeast can generate up to 650 pounds.

“In our PowerPoint slides, we show a stack of oranges the size of the Washington Monument. That’s what it would take to produce the same amount of scent molecules in a two-week fermentation,” Allylix president Carolyn Fritz says.

Until recently the flavor and fragrance industries have relied heavily on chemistry to produce alternatives to natural products. Biotechnology may provide a more sustainable and cheaper option. “This is a new tool in our toolbox,” says Thierry Audibert, head of fragrance science and technology at Givaudan, the world’s largest fragrance supplier, whose clients include Armani and Dior.

As Audibert explains, the fragrance industry had for years been closely watching the burgeoning field of synthetic biology, a discipline that allows scientists to more easily manipulate genes in plants and microorganism­. The breakthrough came in 2006, when Amyris, an early synthetic biology company, engineered yeast to replicate the antimalarial found in the Artemisia annua plant, an East Asian shrub. “This was one of the scientific milestones that gave us the opportunity to dream,” says Audibert. “A microorganism can be considered a chemical factory able to produce anything as long as you have the right genetic setup.”

For several years Amyris and competitors like Solazyme focused on using the technology to develop biofuels. Today these companies are still trying to kick-start their fuel businesses, but both have growing cosmetics divisions. Since 2010 Amyris has signed multiple contract agreements with three major flavor and fragrance companies estimated at $47 million. (Amyris declined to name them.) Later this year it will begin producing patchouli fragrance oil derived from its bioengineered yeast. Solazyme already sells a skincare line based on its microalga called Algenist.

There are now 20-plus listed ingredients that are commercialized or in development, and many more being developed in secret. But not everyone is pleased with biotech’s entry into fragrances. A consortium of nongovernmental organizations, among them Friends of the Earth, is advocating for a halt to the selling of products derived from synthetic biology, including fragrances and oils. “This is GMOs 2.0. In the same way consumers are rejecting GMOs, they are likely to reject this as well,” says Dana Perls, food and technology campaigner for the group. Perls is campaigning for a moratorium on vanillin produced from yeast by the Swiss biotech company Evolva.

But that compound, naturally found in vanilla beans, is largely produced chemically today. “They neatly gloss over the fact that 99 percent of the vanillin in the world comes from either petrochemicals or chemically treated paper pulp,” says Evolva chief executive officer Neil Goldsmith.

Together with the Universiti Malaysia Pahang, Evolva has begun researching the scent of agarwood, known as “wood of the gods.” The unusual smell derives from the resin-embedded heartwood of Southeast Asian Aquilaria trees when they are infected with mold. The natural oil can cost as much as $13,608 per pound.

“The industry hasn’t been through a paradigm shift in a long time,” says Goldsmith. “For now we’re helping the flavor and fragrance industries with their supply chains. In time we’ll be helping them create new experiences for people by making molecules that are now not available.”