Wiktionary
rhodopin
n. (context organic compound English) A particular carotenoid.
Wikipedia
Rhodopin
Rhodopin (1,2-dihydro-ψ,ψ-caroten-1-ol) is a carotenoid. It is a major carotenoid of phototropic bacteria such as Rhodomicrobium vannielii and Rhodopseudomonas acidophila strain 7050.