Biologically-Produced Vanillin - But Not From Plants
Each year, about 10,000 tons of vanillin is chemically synthesized. Most of this is used in the food and fragrance industry. However, there is a huge market for “natural” vanillin extracted from vanilla pods, says the director of biotechnology at the German-based firm Symrise.
Commercial vanilla plantations, in countries such as Madagascar and Indonesia, contribute to the 2,200-2,400 ton annual harvest of vanilla pods. But the prized ingredient vanillin constitutes only two percent of this yield, so there are less than 50 tons per year for the whole world. Its rarity makes natural vanillin extremely valuable, worth more than $10,000 per kilogram, and that is without handling costs. But by taking the biotech approach, Symrise has managed to obtain concentrated amounts of “natural” vanillin from ferulic acid, a closely related molecule. This is achieved by classical fermentation catalyzed by a strain of Amycolatopsis bacteria, and can yield more than 10 grams of vanillin per liter. However, ferulic acid still costs around 100 Euros ($120) per kilogram, so the search was on for an alternative and cheaper substrate. At about one tenth the cost of ferulic acid, eugenol was a candidate. Eugenol is, and has been for more than a century, the starting point for the chemical synthesis of vanillin.
The company’s goal was to end up with a “natural” vanillin using biology rather than chemistry. One problem was that eugenol has antimicrobial properties, making fermentation using microorganisms tricky. However, a strain of Pseudomonas isolated from soil did the job. Using this strain in combination with Amycolatopsis, researchers were able to turn relatively worthless eugenol into valuable vanillin - a modern-day spin on alchemy. The additional step of blocking activity of vanillin dehydrogenase led to the accumulation of even larger amounts of vanillin. However, because European legislation insists that products are labeled to reveal any genetically modified organisms involved in their manufacture, Symrise has decided to put further research on hold until the hostility of the European consumer towards such technology subsides.
Nevertheless, this has done little to dampen the optimism of industry leaders. The European biotechnology community should not put off current research projects, says the president of the Danish company Novozymes, one of Europe's biotechnology forerunners. "We have to work hard to convince society" about the benefits of biotechnology. One problem that Europe faces, by contrast with the U.S., is that research is necessarily fragmented. "In the U.S., they can make one big initiative," he said. Without a coherent European strategy to foster industrial biotechnology, Europe will fall behind the U.S. Switching from chemical to biological processes has "very far-reaching potential for the environment.” Biotechnology, he insists, “can bring benefits to the economy, the environment, and society - the so-called ‘triple bottom-line’.” (BioMedNet, 12/4/03 via AgNet).
