Antioxidant Capacity and fatty acid profile of Swinglea glutinosa (BLANCO) MERR, cultivated in Cuba

The small tropical tree Swinglea glutinosa (Blanco) Merr. is a member of the Rutaceae family. Originally brought to South America from Southeast Asia, it is used as an ornamental plant in Cuba and as a natural barrier in rural areas and gardens. Extracts from this tree have been assessed for cytotoxic and antimalarial activity in previous studies but never been evaluated its antioxidant activity. Material and Methods: The antioxidant capacity of the methanolic extracts and the fatty acid composition of leaves and fruits S. glutinosa (Blanco) Merr was investigated. Six different chemical methods were used to determine the antioxidant capacity. The fatty acid composition was analyzed using gas chromatography. Results: The IC50 value of the extracts was determined being 28.2 g/mL to leaf extract and 10 μg/mL to fruit extract (in the DPPH method. The concentration of the extracts resulted in increased in the ferric reducing antioxidant power to both extracts tested. The amount of total phenolic content was detected as 48.5 mg and 35.9 gallic acid equivalent (GAE)/g in the fruit and the leaf extract, respectively; meanwhile the total antioxidant capacity was 94.93 and 75.3 mg ascorbic acid equivalent (AE)/g for fruits and leaves, respectively. The peroxidation lipid assays (FTC and TBA methods) shows highest antioxidant effect for the leaf extract. Conclusions: The results permit to deduce that the fruit extract has highest anti-radical effect and the leaf extract has highest effect against the lipid peroxidation. The major fatty acid in the composition of Swinglea glutinosa was found to be the ω6 (linoleic) and ω9 (oleic) acids by GC analysis, with 0.5 % for both. This study reveals that Swinglea glutinosa is an attractive source of ω fatty acid components, especially the essential ones, as well as of effective natural antioxidants.