title: Sonochemical effects on 14 flavonoids common in citrus: relation to stability.
abstract: The sonochemical effects of ultrasound (US) treatment on 14 flavonoids representing the main flavonoids in citrus fruit were investigated in a standard mixture by stability evaluation of a model system. Degradation products were further tentatively identified by Fourier transform infrared spectroscopy and high-performance liquid chromatography-ultraviolet detection-electrospray ionization tandem mass spectrometry. Thirteen flavonoids (i.e., eriocitrin, narirutin, neohesperidin, quercitrin, eridictyol, didymin, naringenin, luteolin, sinensetin, nobiletin, tangeretin, naringin, and hesperidin) were fairly stable whereas quercetin was degraded significantly by US treatment. The types of solvent and temperature used were important factors that determined the resulting degradation reactions. The degradation rate of quercetin was highest in 80% ethanol aqueous solution and decreased with increasing temperature. Longer US durations caused increases in the extent of quercetin degradation. Liquid height, ultrasonic intensity, pulse length, and duty cycle of US affected degradation rates but did not change the nature of degradation of the flavonoids. Four types of reactions occurred simultaneously for quercetin under US treatment: oxidation, addition, polymerization, and decomposition. Eight degradation products were tentatively identified as dimer, alcohol addition, oxidation, and decomposition products.
authors: College of Biosystems Engineering and Food Science; Zhejiang Key Laboratory for Agro-Food Processing; Fuli Institute of Food Science; Zhejiang R & D Center for Food Technology and Equipment;Zhejiang University, Hangzhou, PR China.
authors: Liping
authors: L
authors: Qiao
authors: Department of Food Science and Technology, Zhejiang University of Technology, Hangzhou, PR China.
authors: Yujing
authors: Y
authors: Sun
authors: College of Biosystems Engineering and Food Science; Zhejiang Key Laboratory for Agro-Food Processing; Fuli Institute of Food Science; Zhejiang R & D Center for Food Technology and Equipment;Zhejiang University, Hangzhou, PR China.
authors: Rongrong
authors: R
authors: Chen
authors: College of Biosystems Engineering and Food Science; Zhejiang Key Laboratory for Agro-Food Processing; Fuli Institute of Food Science; Zhejiang R & D Center for Food Technology and Equipment;Zhejiang University, Hangzhou, PR China.
authors: Yu
authors: Y
authors: Fu
authors: College of Biosystems Engineering and Food Science; Zhejiang Key Laboratory for Agro-Food Processing; Fuli Institute of Food Science; Zhejiang R & D Center for Food Technology and Equipment;Zhejiang University, Hangzhou, PR China.
authors: Wenjuan
authors: W
authors: Zhang
authors: College of Biosystems Engineering and Food Science; Zhejiang Key Laboratory for Agro-Food Processing; Fuli Institute of Food Science; Zhejiang R & D Center for Food Technology and Equipment;Zhejiang University, Hangzhou, PR China.
authors: Xin
authors: X
authors: Li
authors: College of Biosystems Engineering and Food Science; Zhejiang Key Laboratory for Agro-Food Processing; Fuli Institute of Food Science; Zhejiang R & D Center for Food Technology and Equipment;Zhejiang University, Hangzhou, PR China.
authors: Jianchu
authors: J
authors: Chen
authors: College of Biosystems Engineering and Food Science; Zhejiang Key Laboratory for Agro-Food Processing; Fuli Institute of Food Science; Zhejiang R & D Center for Food Technology and Equipment;Zhejiang University, Hangzhou, PR China.
authors: Yan
authors: Y
authors: Shen
authors: College of Biosystems Engineering and Food Science; Zhejiang Key Laboratory for Agro-Food Processing; Fuli Institute of Food Science; Zhejiang R & D Center for Food Technology and Equipment;Zhejiang University, Hangzhou, PR China.
authors: Xingqian
authors: X
authors: Ye
mesh_terms: D002851:Chromatography, High Pressure Liquid; D002957:Citrus / Q000737:chemistry*; D005419:Flavonoids / Q000032:analysis* / Q000737:chemistry; D011794:Quercetin / Q000032:analysis / Q000737:chemistry; D012997:Solvents; D021241:Spectrometry, Mass, Electrospray Ionization; D017550:Spectroscopy, Fourier Transform Infrared; D013696:Temperature; D013997:Time Factors; D014465:Ultrasonics
chemical_list: D005419:Flavonoids; D012997:Solvents; D011794:Quercetin