Erysimum collinum

In a 2014 taxonomic revision, E. aucherianum, E. gayanum, E. gracile, and E. passgalense are considered to be the same species as E. collinum.^[3] The revised species has both diploid (2n = 14) and hexaploid (2n = 42) members.^[5] Based on sequence comparisons of expressed genes in 48 Erysimum species, E. collinum is most closely related to E. crassipes and E. crassicaule.^[11]

The genus Erysimum is known for containing two major classes of defensive metabolites: glucosinolates, which are characteristic of all Brassicaceae, and cardiac glycosides (cardenolides), which are found only within the genus Erysimum.^[12] However, unlike other analyzed members of the genus Erysimum, E. collinum contains only trace amounts of cardiac glycosides (cardenolides).^[11] Nevertheless, extracts of E. collinum showed some inhibitory activity of the mammalian sodium-potassium ATPase pump (Na⁺/K⁺-ATPase), the main molecular target of cardenolides.^[11]

The most abundant glucosinolate in E. collinum is glucoerypestrin (3-methoxycarbonylpropyl glucosinolate),^[11] which has been reported only within the genus Erysimum,^[13] including also in the species E. repandum (syn. E. pulchellum), E. odoratum, and E. ochroleucum.^{[11][13][14][15]} Other glucosinolates found in E. collinum are indol-3-ylmethyl glucosinolate, 4-methoxyindol-3-ylmethyl glucosinolate, 3-methylsulfinylpropyl glucosinolate, 2-methylpropyl glucosinolate, and n-methylbutyl glucosinolate.^[11]