The hunt is on for vaccine ingredients that don’t come from wild sharks

Potential replacements for squalene, a shark-derived vaccine ingredient, have been developed by scientists in the US. Squalene is used in adjuvants to boost immune responses, but it is sourced from wild caught sharks, including those under threat from overfishing.

Squalene is a natural terpene found in many plants and animals but are especially abundant in shark liver. To avoid the need to use squalene from sharks, the team created analogues of the compound from ß-farnesene, a compound derived from yeast fermentation. Chemical synthesis was then used to convert it into 20 different analogues of squalene. ß-farnesene is already made commercially using yeast by Amyris, a US biotech which produces a squalene-like compound for cosmetics: squalane.