Title : Chemical composition and antioxidant activity of steam distilled essential oil and glycosidically bound volatiles from Maclura tricuspidata frui
Abstract:
The objective of this study was to determine chemical composition and antioxidant activities of steam distilled essential oil (SDEO) and glycosidically bound aglycone fraction (GBAF) isolated from fully ripe Maclura triscuspidata fruit. SDEO was isolated by simultaneous steam distillation and extraction (SDE). GBAF was prepared by Amberlite XAD-2 adsorption of methanol extract, followed by methanol elution and enzymatic hydrolysis using Aspgillus niger cellulase, Both fractions were analyzed by gas chromatography (GC) and gas chromatographymass spectrometry (GC-MS). A total of 76 constituents were identified from both oils. The SDEO contained p-cresol (383.5 ± 17.7 ug/g) in the highest concentration, followed by δ-cadinene (147.7 ±7.7 ug/g), β-caryophyllene (145.7 ±10.5), β-ionone (141.0 ± 4.5 ug/g), n-nonanal (140.3 ±20.5 ug/g), theaspirane A (121.3± 4.5 ug/g) and theasprane B (99.67 ± 9.05 ug/g), excepting fatty acid and their esters. Especially, 10 carotenoid-derived compounds were identified in SDEO of M. triscuspidata fruit for the first time in this study. A total of 22 components were identified from GBAF with p-methylsalicylaldehyde, α-methoxy-p-cresol, 2-methyl-1-butanol, benzyl alcohol, 9-hydroxymegastigma-4,6- dien-3-ones (2 isomers) and p-hydroxybenzyl alcohol as major components and also almost of components identified in GBAF fraction were identified for the first time as constituents of M. triscuspidata fruit. The antioxidant activity in GBAF was higher than those of SDEO, and potent antioxidant activity in GBAF has been determined to be primarily due to presence of phenolic compounds such as α-methoxy-p-cresol, vanillyl alcohol, ferulic acid and pyrocatechol. These results suggest that intake of antioxidant-rich preparations from M. triscuspidata fruit are beneficial to human health.
