title: Ionic-liquid-based ultrasound/microwave-assisted extraction of 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one and 6-methoxy-benzoxazolin-2-one from maize (Zea mays L.) seedlings.
abstract: We evaluated an ionic-liquid-based ultrasound/microwave-assisted extraction method for the extraction of 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one and 6-methoxy-benzoxazolin-2-one from etiolated maize seedlings. We performed single-factor and central composite rotatable design experiments to optimize the most important parameters influencing this technique. The best results were obtained using 1.00 M 1-octyl-3-methylimidazolium bromide as the extraction solvent, a 50°C extraction temperature, a 20:1 liquid/solid ratio (mL/g), a 21 min treatment time, 590 W microwave power, and 50 W fixed ultrasonic power. We performed a comparison between ionic-liquid-based ultrasound/microwave-assisted extraction and conventional homogenized extraction. Extraction yields of 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one and 6-methoxy-benzoxazolin-2-one by the ionic-liquid-based ultrasound/microwave-assisted extraction method were 1.392 ± 0.051 and 0.205 ± 0.008 mg/g, respectively, which were correspondingly 1.46- and 1.32-fold higher than those obtained by conventional homogenized extraction. All the results show that the ionic-liquid-based ultrasound/microwave-assisted extraction method is therefore an efficient and credible method for the extraction of 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one and 6-methoxy-benzoxazolin-2-one from maize seedlings.
authors.affiliation: Key Laboratory of Forest Plant Ecology, Ministry of Education, Northeast Forestry University, Harbin, China.
authors.forename: Chunying
authors.initials: C
authors.lastname: Li
authors.forename: Zhicheng
authors.initials: Z
authors.lastname: Lu
authors.forename: Chunjian
authors.initials: C
authors.lastname: Zhao
authors.forename: Lei
authors.initials: L
authors.lastname: Yang
authors.forename: Yujie
authors.initials: Y
authors.lastname: Fu
authors.forename: Kunming
authors.initials: K
authors.lastname: Shi
authors.forename: Xin
authors.initials: X
authors.lastname: He
authors.forename: Zhao
authors.initials: Z
authors.lastname: Li
authors.forename: Yuangang
authors.initials: Y
authors.lastname: Zu
mesh_terms: D048588:Benzoxazines / Q000302:isolation & purification*; D001583:Benzoxazoles / Q000302:isolation & purification*; D002851:Chromatography, High Pressure Liquid; D052578:Ionic Liquids; D008855:Microscopy, Electron, Scanning; D008872:Microwaves; D013056:Spectrophotometry, Ultraviolet; D014465:Ultrasonics; D003313:Zea mays / Q000737:chemistry* / Q000254:growth & development
chemical_list: D048588:Benzoxazines; D001583:Benzoxazoles; D052578:Ionic Liquids; C031896:6-methoxybenzoxazolinone; C050733:2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one
keywords: Benzoxazinoids; Extraction; Ionic liquids; Maize seedlings