Phytosterol content of sea buckthorn (Hippophae rhamnoides L.) seed oil: Extraction and identification

Phytosterols in sea buckthorn (Hippophae rhamnoides L.) seed oil extracted by cold pressing, hexane, and supercritical carbon dioxide were identified by GC–MS and FID. Compounds identified were campesterol, clerosterol, lanosterol, sitosterol, β-amyrin, sitostanol, Δ5-avenasterol, Δ24(28)-stigmasta-en-ol, α-amyrin, Δ5,24(25)-stigmastadienol, lupeol, gramisterol, Δ7-sitosterol, cycloartenol, cycloeucalenol, Δ7-avenasterol, 28-methylobtusifoliol, 24-methylenecycloartanol, erythrodiol, citrostadienol, uvaol, and oleanol aldehyde. Sitosterol and Δ5-avenasterol were, quantitatively, the most important phytosterols. Total sterols and most individual sterols differed significantly (P ⩾ 0.05) among all three extraction methods with supercritical carbon dioxide extracting the highest total sterol levels (1640 mg/100 g oil) and cold pressed the lowest levels (879 mg/100 g oil).