Lithospermum officinale L. is a versatile source of γ-linolenic- and
stearidonic acid-rich oils
Abstract
Seeds of Lithospermum officinale L. from different climatic zones were
analyzed looking for new sources γ-linolenic acid (GLA, 18:3n-6) and
stearidonic acid (SDA, 18:4n-3). Cultured B. officinalis was also
analyzed with comparative purposes. Analyses were conducted for fatty
acid (FA) profiles in the whole seeds and in the neutral and polar
lipids by GC; lipid classes by open column chromatography and
preparative TLC; and tocopherols, sterols and phenolic compounds by
HPLC-DAD, and the later compounds were confirmed by LC-MS. The richest
GLA sample was L. officinale from St. Petersburg Botanical Garden
(17.9% of total FA), while wild-growing L. officinale from the Rostov
region showed the highest percentage of SDA (17.2% of total FA). Total
FA content ranged from 11.3 to 20.8% of seed weight. Neutral and polar
lipids accounted for ~98 and 2.27% of total lipids.
Five neutral lipid classes were identified (% of NL): triterpene
esters, 1.3; triacylglycerols, 93.1; free FA, 1.8; diacylglycerols, 1.4;
and monoacylglycerols, 2.4. Tocopherols and sterols reached 35.7 and
83.8 mg/100 g seeds; γ-tocopherol was the main tocopherol detected, and
Δ5-avenasterol was the predominant sterol. L. officinale seeds contain
high amounts of phenolic compounds (389.9 mg/100 g as upper limit), in
which rosmarinic acid was the main component. Overall, all data suggest
the possibility of using L. officinale seed oil in pharmaceutical and
cosmetic formulae and as functional food.