Those of us of a “certain age” may soon be more often reminded of our high school and college days as wafts of “hippie smell” become more common. That’s because large volumes of patchouli oil are about to be synthetically produced, allowing it to be used on a larger scale in common consumer products.Patchouli oil, derived from the patchouli plant has been cultivated in basically the same way for centuries, but these traditional methods result in a supply that is unreliable and of inconsistent quality. That’s why synthetic biology company, Amyris, and Firmenich, a large flavor and fragrance company have teamed up to develop an innovative bioprocess that can produce large, quality volumes of patchouli oil from yeast.Two terpenes, patchoulol and norpatchoulenol are the main contributors to patchouli oil’s scent. Firmenich’s patent application reveals how terpenes can be produced using microbial fermentation. A bacterium such as Escherichia coli or a yeast such as Saccharomyces cerevisiae can be engineered for isoprenoid production by insertion of one of two genetic pathways used by plants to make terpene precursors. The microbe gets genes coding for a terpene synthase, an enzyme that makes a particular terpene from one or more precursors. The resulting terpene can be functionalized through hydroxylation, isomerization, oxidation, reduction, or acylation.Like patchouli, supplies of other fragrant oils, such as bitter orange, grapefruit, rose, and sandalwood can also be subject to shortages and price swings due to bad weather, natural disasters and even poaching and government corruption in areas where these are grown. This is when leading flavor and fragrance companies to turn to biotechnology start-ups to produce a wide variety of plant-derived molecules. In fact, Kalib Kersh, an analyst at Boston-based Lux Research says, “There is potential for biosynthetic routes to completely replace any natural sources.”