HPLC法测定马铃薯块茎中糖苷生物碱的含量

摘要

商品马铃薯中主要含有2种糖苷生物碱，α-卡茄碱和α-茄碱，是由相同的糖苷配基茄啶组成的三糖。这2种物质占马铃薯块茎中糖苷生物碱的95%，其水解产物，β-、γ-形式的糖苷生物碱以及茄啶所占的比例相对很低。采用改正的HPLC法测定了马铃薯块茎中α-卡茄碱和α-茄碱的含量，条件为柱子，Inertsil NH2（5μm，4.0 mm ×250 mm）；流动相，乙腈/20 mmol KH2PO4（80��20，v/v）；流速，1.0 mL/min；柱温，室温；二极管阵列检测器，210 nm；进样量，20μL。结果表明，重量为116.98 g，1/4表皮发绿长有一个5 mm芽的‘陇薯3号’马铃薯块茎当中α-卡茄碱的含量为150.07 mg/kg，α-茄碱的含量为57.80 mg/kg，2种糖苷生物碱的总和为207.87 mg/kg。该改正的HPLC法可用于准确测定马铃薯块茎中糖苷生物碱的含量。%There are two major glycoalkaloids,α-chaconine andα-solanine in commercial potatoes, both of them being trisaccharides of the common aglycone solanidine . These two compounds comprise about 95%of the glycoalkaloids in potato tubers. Their hydrolysis products,β-andγ-forms and solanidine, may also be presented in relatively insignificant concentrations. An improved HPLC was used to detect the glycoalkaloids in potato tuber. The conditions are column, Inertsil NH2 (5μm, 4.0 mm × 250 mm);mobile phase, acetonitile/20 mmol KH2PO4 (80:20, v/v);flow rate, 1.0 mL/min;column temperature, room temperature;PAD detector, 210 nm;and sample size, 20μL. The results indicated that a potato tuber of the cultivar 'Longshu 3' with 1/4 green peel and a 5 mm sprout contained 150.07 mg/kg ofα-chaconine and 57.80 mg/kg ofα-solanine, with the total glycoalkaloids content being 207.87 mg/kg. This improved HPLC method could be used to detect the total glycoalkaloids accurately.