CAJ | 학술논문

目的：建立婴幼儿乳粉中色氨酸的超高效液相色谱检测方法,并考察乳粉中色氨酸含量与蛋白质含量的相关性。方法样品在145℃下碱性水解4 h,经C18色谱柱(50 mm×4.6 mm,1.8μm)分离。以100 mmol/L KH2PO4-NaOH缓冲溶液-甲醇为流动相,40%甲醇(v：v)等度洗脱,流速为0.5 mL/min,进样量5μL,柱温45℃。荧光检测器检测,激发波长280 nm；发射波长350 nm。结果方法在1~1000μg/L范围内线性关系良好(r=0.999)；定量限为1μg/L。添加浓度在0.2、0.5、1.5 mg/g时,色氨酸的回收率介于110.7%~116.3%之间。结论本方法操作简便,可应用于市售乳粉样品中色氨酸含量的测定。对市售样品的测定结果表明,部分婴幼儿乳粉样品的色氨酸含量低于国家限量,此外,乳粉中色氨酸含量与蛋白质含量之间并不呈线性相关。
목적：건립영유인유분중색안산적초고효액상색보검측방법,병고찰유분중색안산함량여단백질함량적상관성。방법양품재145℃하감성수해4 h,경C18색보주(50 mm×4.6 mm,1.8μm)분리。이100 mmol/L KH2PO4-NaOH완충용액-갑순위류동상,40%갑순(v：v)등도세탈,류속위0.5 mL/min,진양량5μL,주온45℃。형광검측기검측,격발파장280 nm；발사파장350 nm。결과방법재1~1000μg/L범위내선성관계량호(r=0.999)；정량한위1μg/L。첨가농도재0.2、0.5、1.5 mg/g시,색안산적회수솔개우110.7%~116.3%지간。결론본방법조작간편,가응용우시수유분양품중색안산함량적측정。대시수양품적측정결과표명,부분영유인유분양품적색안산함량저우국가한량,차외,유분중색안산함량여단백질함량지간병불정선성상관。
ObjectiveTo establish an ultra-high performance liquid chromatography (U-HPLC) method for the determination of tryptophan in infant formulas, and then to investigate the relationship between trypto-phan concentration and protein concentration in infant formulas.Methods NaOH was used as hydrolytic so-lution. Then sample hydrolysis under an alkaline condition at 145℃. The U-HPLC separation was achieved using a C18 column (50 mm×4.6 mm, 1.8μm) as solid phases and KH2PO4-NaOH buffer solution-methanol (60:40,v:v) as mobile phases. under isocratic elution. The flow rate was 0.5 mL/min and the column oven tem-perature was 45℃. The injection volumn was 5μL. It was detected on a Fluorescence Detector and quantita-tively determined by the peak area at excitation wavelength of 280 nm and emission wavelength of 350 nm. Results The linear concentration ranges of the calibration curve were 1~1000 μg/L for tryptophan (r=0.999), and the limit of quantification of the method was 1μg/L. The mean recoveries varied from 110.7%~116.3% when spiked negative samples with 0.05, 0.5 and 2.5 mg/g tryptophan.Conclusion The established method is simple and can be suitable for the rapid determination of tryptophan in infant formulas. The determined results demonstrated that the relationship was not linear between tryptophan concentration and protein concentration in infant formulas.