College of Pharmacy, Youjiang Medical University for Nationalities, Baise 533000, China.
Guangxi Database Construction and Application Engineering Research Center for in Tracorporal Pharmacochemistry of TCM, Baise 533000, China.
Molecules. 2023 Jul 10;28(14):5309. doi: 10.3390/molecules28145309.
--hydroxycinnamic acid and its esters in the leaves of might be a new resource to prevent diabetes and its complications. In the present study, a new HPLC-UV method using hydrolyzation with sodium hydroxide for quantitation of --hydroxycinnamic acid and total --hydroxycinnamic acid esters in the leaves of was developed, since it was difficult and troublesome to analyze no less than 34 --hydroxycinnamic acid esters by usual HPLC. The extract of was hydrolyzed with sodium hydroxide at 80 °C for 2 h, and then, hydrochloride was added. HPLC analysis was performed in reverse phase mode using a C-18 column, eluting with methanol-0.1% acetic acid aqueous solution (40:60, /) in isocratic mode at a flow rate of 1.0 mL·min and detecting at 310 nm. The linear range for --hydroxycinnamic acid was 11.0-352.0 μg·mL ( = 1.000). The limit of detection and limit of quantification were 2.00 and 6.07 μg·mL, respectively. The relative standard deviations of intra-day and inter-day variabilities for --hydroxycinnamic acid were less than 2%. The percentage recovery of --hydroxycinnamic acid was 103.3% ± 1.1%. It is the first HPLC method using hydrolyzation for quantification of many carboxylic esters. Finally, the method was used successfully to determine --hydroxycinnamic acid and total --hydroxycinnamic acid esters in various extracts of the leaves of . The 60-70% ethanol extracts of showed the highest contents of free --hydroxycinnamic acid (3.96-3.99 mg·g), and the 50-80% ethanol extracts of displayed the highest contents of total --hydroxycinnamic acid esters (202.6-210.6 mg·g). The method can be applied also to the quality control of the products of .
--羟基肉桂酸及其酯类在 叶子中可能是预防糖尿病及其并发症的新资源。本研究采用氢氧化钠水解法建立了一种新的 HPLC-UV 方法，用于定量分析 叶子中的 --羟基肉桂酸和总 --羟基肉桂酸酯类，因为用通常的 HPLC 分析不少于 34 种 --羟基肉桂酸酯类既困难又麻烦。将 提取物在 80°C 下用氢氧化钠水解 2 小时，然后加入盐酸。HPLC 分析在反相模式下进行，使用 C-18 柱，以甲醇-0.1%乙酸水溶液（40:60，/）等度洗脱，流速为 1.0 mL·min，在 310nm 处检测。--羟基肉桂酸的线性范围为 11.0-352.0 μg·mL（ = 1.000）。检测限和定量限分别为 2.00 和 6.07 μg·mL。--羟基肉桂酸日内和日间变异性的相对标准偏差均小于 2%。--羟基肉桂酸的回收率为 103.3%±1.1%。这是首次采用水解法定量分析多种羧酸酯的 HPLC 方法。最后，该方法成功地用于测定 不同提取物中--羟基肉桂酸和总--羟基肉桂酸酯类的含量。 60-70%乙醇提取物中游离 --羟基肉桂酸（3.96-3.99mg·g）含量最高，50-80%乙醇提取物中总 --羟基肉桂酸酯（202.6-210.6mg·g）含量最高。该方法也可用于 的产品质量控制。
