Résumé:
Background: Lawsonia alba seed oils are not widely used commercially even though they
have characteristics that well suit for industrial applications and can contribute to healthy human
diets. The most important aim of the present work is the evaluation of the tocopherols composition of
these oils. Moreover, lipid classes, fatty acids compositions and antioxidant activity of the seed oils
were also investigated.
Methods: Lawsonia alba seed oils were extracted with Soxhlet device using n-hexane and
chloroform/methanol. Tocopherols were analyzed by HPLC The antioxidant activity were
determined using two different assays: DPPH (1,1-diphenyl-2-picrylhydrazyl), and Phosphomolybdenum.
Results: The content of the oils ranged from 7.52 to 10.45%. Polyunsaturated fatty acids dominated
all the studied samples. Linoleic, followed by palmitic and oleic, were the major fatty acids found in
the crude seed oils and their lipid classes. Results of tocopherols identification showed that the seed
oils were rich in tocopherols, especially - and - tocopherols. For DPPH assay, the antioxidant
powers varied from medium to low values (IC50 = 0.11 to 16.54 mg/mL). The results of the
Phosphomolybdenum assay showed very important activities of the oils that were decreasing in the
following order: polar lipids > neutral lipids (Chloroform/Methanol) > total lipids > neutral lipids
(n-hexane).
Conclusion: this current report reveals the richness of the Lawsonia alba seeds in tocopherols, which
in fact is studied for the first time. Moreover, cluster analysis revealed that fatty acid composition of
the seed oils of Lawsonia alba were very close to those of Walnut.
