Ambergris is a waxy substance excreted by the intestinal tract of the sperm whale and has been a highly prized fragrance ingredient for millennia. It has a sought after scent and enhances other scents in high-end perfumes.
Due to the demand for ambergris substitutes in the perfume industry, Laurent Daviet, Michel Schalk and colleagues set about finding a sustainable method of producing such ingredients more effectively.
Their study reports the cloning and functional characterization of the enzymes responsible for the biosynthesis of sclareol; one of the aforementioned substitutes.
Sclareol is obtained from the Clary sage plant; however, the plant contains only small amounts of sclareol, and it is laborious to extract and purify.
With this in mind, the researchers looked for a better way of making large amounts of sclareol.
They reconstructed the sclareol biosynthetic pathway in genetically engineered Escherichia coli and reached sclareol titers of 1.5 g/L in high-cell-density fermentation.
“Our work provides a basis for the development of an alternative, sustainable, and cost-efficient route to sclareol and other diterpene analogues,” say the team.
The study was published in the Journal of the American Chemical Society, and states that the advance enables cultures of bacteria to produce a substitute for natural ambergris, which sells for hundreds of dollars an ounce.
The report describes isolating the genetic material (DNA) that produces the two Clary sage enzymes needed to make sclareol. They put the DNA into bacteria, which made large amounts of sclareol in bioreactors.
The need to produce alternatives to the fragrance ingredient is down to sperm whales being an endangered species, and the fact that natural ambergris is not used in perfumes in the US and many other markets around the world.
Also, because of supply shortage and price inflation, a number of ambergris substitutes have been developed by the fragrance industry that are more cost effective.