(-)-Rotundone, an Important Odor Active Constituent

of Agarwood (Oud), is now FEMA GRAS


Research Note by John Leffingwell - January 16, 2017

(-)-Rotundone ((3S,5R,8S)-3,8-Dimethyl-5-prop-1-en-2-yl-3,4,5,6,7,8-hexahydro-2H-azulen-1-one) is an important odor active constituent of Agarwood (Oud), white & black peppercorns, patchouli oil, Cypriol oil (Cyperus scariosus) as well as various wines that exhibit peppery spicy notes. It also is reported as being important to oak aged spirits.

In recent years, the use of cypriol oil in perfumery has increased because of its unique woody, ambery, and earthy character that is appreciated by perfumers as an alternative to the more expensive agarwood oil. Of the constituents, rotundone was the the most odor active. Robin Clery & coworkers have described the odor using GC-O as "woody, peppery, agarwood like".

In 2006, Roman Kaiser also reported that "rotundone, a compound characterized by a very low recognition threshold value and already long known as a constituent of patchouli oil, is also very important to this part of the agarwood scent".

In 2008, the aroma detection threshold for rotundone was determined by Wood et. al., with the best estimated threshold of 16 ng/L in red wine and 8 ng/L= 0.008 ppb in water. While most of the 47 sensory panelists were very or moderately sensitive to rotundone, approximately 20% could not detect this compound at the highest concentration tested (4000 ng/L).

In December 2016, rotundone was assigned FEMA No. 4867 for the new Interim FEMA GRAS™ 28 List.

The odor of a number of other important agarwood constituents have been reviewed by Roman Kaiser; John Leffingwell; Regula Naef; and most recently by Michae Zviely and Arcadi Boix-Camps.

The December 2016 Interim FEMA GRAS 28 List can be accessed at

FEMA = Flavor & Extract Manufacturers Association

GRAS = Generally Recognized As Safe


Wood, C., T. E. Siebert, M. Parker, D. L. Capone, G. M. Elsey, A. P. Pollnitz, M. Eggers, M. Meier, T. Vössing, S. Widder, S. and G. Krammer. "Spice up your life–The Rotundone story." Expression of Multideisciplinary flavour science, Proceedings of the 12th Weurman Symposium, 2008: 483-485; Siebert, Tracey E., Claudia Wood, Gordon M. Elsey, and Alan P. Pollnitz. "Determination of rotundone, the pepper aroma impact compound, in grapes and wine." Journal of agricultural and food chemistry 56, no. 10 (2008): 3745-3748; Wood, Claudia, Tracey E. Siebert, Mango Parker, Dimitra L. Capone, Gordon M. Elsey, Alan P. Pollnitz, Marcus Eggers et al. "From wine to pepper: rotundone, an obscure sesquiterpene, is a potent spicy aroma compound." Journal of Agricultural and Food Chemistry 56, no. 10 (2008): 3738-3744.

Sundaresan, V., S. P. Singh, A. N. Mishra, Ajit K. Shasany, Mahendra P. Darokar, Alok Kalra, and A. A. Naqvi. "Composition and comparison of essential oils of Pogostemon cablin (Blanco) Benth.(Patchouli) and Pogostemon travancoricus Bedd. var. travancoricus." Journal of Essential Oil Research 21, no. 3 (2009): 220-222.

Genthner, Elizabeth Robyn, Identification of rotundone as an important contributor to the flavor of oak aged spirits, Ph.D. Dissertation, University of Illinois at Urbana-Champaign, 2014.

An-Cheng, Mark A. Sefton, and Dennis K. Taylor. "Comparison of the formation of peppery and woody sesquiterpenes derived from a-guaiene and alpha-bulnesene under aerial oxidative conditions." Journal of agricultural and food chemistry 63, no. 7 (2015): 1932-1938.

Kaiser, Roman, Agarwood - the Wood of the Gods, in Meaningful Scents around the World. Olfactory, Chemical, Biological, and Cultural Considerations (Zürich: Helvetica Chimica Acta, Weinheim: Wiley-VCH, 2006):pp 59-64.

Leffingwell, John C. "Chirality and odor perception-Scents of precious woods." CHIMICA OGGI-CHEMISTRY TODAY 24, no. 4 (2006): 36-38.

Naef, Regula. "The volatile and semi-volatile constituents of agarwood, the infected heartwood of Aquilaria species: a review." Flavour and Fragrance Journal 26, no. 2 (2011): 73-87.

Zviely, Michael and Arcadi Boix-Camps, Sesquiterpenoides - the holy fragrance ingredients, The Israel Chemist and Engineer, Issue 1, (September 2015, Tishrei 5776): 27-31.