Lipoxidation caused by ultrasound treatment was investigated. Its effects on total phenol content (TPC), total flavonoid content (TFC), antioxidant activity (AA) and phenols extraction kinetics in Tartary buckwheat extracts were also studied. Malondialdehyde (MDA) levels and peroxide value (PV) were used to measure lipoxidation. Kinetic modeling of phenol extraction was also done according to Fick's second law of diffusion. Increasing treatment time increased TPC, TFC and AA significantly (p < 0.05) and increments in MDA and PV were significant after 45 min. Increases in MDA and PV correlated with reductions in TPC, TFC and AA. Phenol diffusion followed a kinetic curve that agrees with the classical solid-liquid extraction models, with a rapid initial phase and a slow phase at the end. The effective diffusion coefficients (D_e), both D_e-rapid and D_e-slow, for phenols positively correlated with time (5–60 min) and temperature (20–80 °C). TPC increased when extraction temperature and time increased with D_e-rapid from 3.30 to 7.97 × 10¹¹ m²s^-1 from 20 to 80 °C and 2.88 to 7.47 × 10¹¹ m²s^-1 from 5 to 60 min. The D_e-slow phase also increased from 2.02 to 5.21 × 10¹² m²s^-1 and 2.85 to 4.33 × 10¹² m²s^-1, respectively, for the same range of extraction temperatures and times. It is recommended that ultrasound assisted extraction of phenols from polyunsaturated fatty acid-rich sources are done at temperatures below 65 °C and not for extended periods to preserve bioactivity and minimize lipoxidation.

研究了超声处理引起的脂质氧化。还研究了其对苦荞提取物中总酚含量（TPC），总黄酮含量（TFC），抗氧化活性（AA）和酚提取动力学的影响。丙二醛（MDA）水平和过氧化值（PV）用于测量脂氧化。还根据菲克第二扩散定律对苯酚萃取进行了动力学建模。延长治疗时间会使TPC，TFC和AA显着增加（p <0.05），MDA和PV的增加在45分钟后显着。MDA和PV的增加与TPC，TFC和AA的减少相关。苯酚的扩散遵循动力学曲线，该曲线与经典的固液萃取模型相吻合，初始阶段为快速，而缓慢阶段为结束。有效扩散系数（D_e），D _e-rapid和D _e-slow，对于酚而言，与时间（5-60分钟）和温度（20-80°C）呈正相关。当D _e-rapid从20到80°C从3.30升高到7.97×10 ¹¹ m ² s ^-1，从5到60 min从2.88升高到7.47×10 ¹¹ m ² s ^-1时，TPC升高。D _e-slow相也从2.02增加到5.21×10 ¹² m ² s ^-1，从2.85增加到4.33×10 ¹² m ² s ^-1分别针对相同的提取温度和时间范围。建议在低于65°C的温度下，超声辅助提取富含多不饱和脂肪酸的苯酚，而不是延长提取时间以保持生物活性并最大程度地减少脂氧化。