甜玉米多酚类成分的测定

Analysis of Polyphenol Composition of Different Parts of an Ear of Sweet Corn

用高效液相色谱法测定甜玉米肉粒、芯、苞衣及须中的多酚类成分,采用AgilentZORBAXSB-C18分析柱(4.6mm×250mm,5μm),流动相:A相乙腈、B相0.4%乙酸,0～40min为5%A～95%B,40～45min为25%A～75%B,45～50min为35%A～65%B,后运行时间5min,流速1.0mL/min;VWD检测器,检测波长280nm;柱温30℃。在甜玉米粒中检测到13种多酚类化学成分,其中包括龙胆酸、芦丁、槲皮素、表儿茶素、绿原酸、香草酸、安息香酸、丁香酸、儿茶素、金丝桃苷、没食子酸、咖啡酸、阿魏酸;而在在甜玉米苞衣和芯中检测到12种多酚类成分,在甜玉米须中检测到8种多酚类成分。

A HPLC method was developed for the analysis of polyphenol composition of different parts of an ear of sweet corn including kernels, cob, silk and leafy husk. The chromatographic separation was performed on an Agilent ZORBAX SB-C18 column （4.6 × 250 mm, 5μm） with a binary mobile phase composed of a mixture of 0.4% aqueous solution （phase A） of acetic acid and acetonitrile （phase B） leading to the following gradients： 0-40 min, phase A 5% ＋ phase B 95%; 40-45 min, phase A 25% ＋ phase B 75%; and 45-50 min followed by 5 min running, phase A 35% ＋ phase B 65% at a flow rate of 1.0 mL/min. Column temperature was set at 30 ℃. The VWD detection was performed at a wavelength of 280 nm. Added together, 13 phenolic compounds were identified in sweet corn kernels, cob, silk and leafy husk, including gentisic acid, rutin, quercetin, picatechin, vanillic acid, benzoic acid, syringic acid, catechin, hyperoside, gallic acid, caffeic acid and ferulic acid, of which, 12 were identified in sweet cob or leafy husk and 8 in sweet silk.