Ambrein

Ambergris is an organic substance secreted from the digestive system of the sperm whale (Physeter macrocephalus), the only surviving species in its genus. It has a fecal odor when fresh, but as it ages it acquires a sweet aroma. It is often used as a fixative in perfumes to make the scent last longer.

The quest for ambergris (as well as for whalebone and whale oil) caused the sperm whale to become an endangered species in the 20th century. As a result, the Endangered Species Act of 1973 prohibited its possession and sale in the United States.

In 1946, chemists Leopold Ružička (a 1939 Nobel laureate) and F. Lardon at ETH Zurich reported that ambergris has three main components: the triterpene alcohol ambrein, the steroid alcohol epicoprostanol, and the steroid ketone coprostanone. Ambrein has only a mild scent, but it can be oxidized to produce the odor components ambroxide and ambrinol. Ambroxide (trade name Ambroxan) is widely used in the perfume industry; but because ambrein is now scarce, the industry relies on synthetic ambroxide.

But ambrein may have a second life. In 2019, Harald Pichler and colleagues at the Austrian Center of Industrial Biotechnology (Graz), Graz University of Technology, and ACS International (Plan‐les‐Ouates, Switzerland) engineered the yeast Saccharomyces cerevisiae to synthesize ambrein from squalene in good yields. In the long run, this may be a better way to produce ambroxide on a large scale.

Ambrein is not an article of commerce; hence hazard information for it is not readily available.