Abstract Carpaine, the major alkaloid present in Carica papaya leaves, have recently been shown to have antiplasmodial activity. Traditionally, water decoctions of papaya leaves (boiling in water) have been used as a malaria preventative. In this paper Carpaine from the shade-dried leaves of C. papaya have been isolated, characterized, and quantified. A rapid, sensitive, and reproducible high-performance thin-layer chromatography (HPTLC) method was developed for the bioactive marker. Chloroform:methanol (70:30, v/v) was used as the mobile phase over pre-coated HPTLC silica gel F254 plates. The plates were developed to a distance of 60 mm at 23 ± 4 °C in a chamber previously saturated for 20 min. Under these conditions, the retention factor (Rf) of Carpaine was 0.59 and it was quantified at 550 nm, its wavelength of maximum absorbance after derivatization with Dragendorff’s reagent. Carpaine showed a linear function of the amount over the range 400–1200 ng per band; the correlation coefficient was 0.99451, indicating a good linear relationship between peak area and amount. The method was validated for precision, repeatability, and accuracy. The recovery percentage of Carpaine was found to be 101.56% w/w. It is found to be present 0.52% (w/w) in shade-dried leaves, 5.02% (w/w) in processed extract and 0.04% (w/w) in the Zandu Papaya tablet (commercial formulation). GRAPHICAL ABSTRACT

中文翻译：

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通过 HPTLC 光密度测定法从 Carica papaya L. 及其商业配方中分离和定量生物活性 Carpaine

摘要 Carpaine 是 Carica papaya 叶中存在的主要生物碱，最近已被证明具有抗疟原虫活性。传统上，木瓜叶的水煎剂（在水中煮沸）已被用作疟疾预防剂。在本文中，来自 C. papaya 遮荫干燥的叶子中的 Carpaine 已被分离、表征和量化。为生物活性标记物开发了一种快速、灵敏且可重现的高效薄层色谱 (HPTLC) 方法。氯仿:甲醇 (70:30, v/v) 在预涂 HPTLC 硅胶 F254 板上用作流动相。在预先饱和 20 分钟的腔室中，在 23 ± 4 °C 下将板显影至 60 mm 的距离。在这些条件下，Carpaine 的保留因子 (Rf) 为 0.59，并在 550 nm 处定量，用 Dragendorff 试剂衍生后的最大吸光度波长。Carpaine 在每条带 400–1200 ng 范围内显示出数量的线性函数；相关系数为 0.99451，表明峰面积与量之间具有良好的线性关系。对该方法的精密度、重复性和准确度进行了验证。发现 Carpaine 的回收率为 101.56% w/w。发现它在阴凉干燥的叶子中含量为 0.52% (w/w)，在加工提取物中含量为 5.02% (w/w)，在 Zandu Papaya 片剂（商业配方）中含量为 0.04% (w/w)。图形概要 对该方法的精密度、重复性和准确度进行了验证。发现 Carpaine 的回收率为 101.56% w/w。发现它在阴凉干燥的叶子中含量为 0.52% (w/w)，在加工提取物中含量为 5.02% (w/w)，在 Zandu Papaya 片剂（商业配方）中含量为 0.04% (w/w)。图形概要 对该方法的精密度、重复性和准确度进行了验证。发现 Carpaine 的回收率为 101.56% w/w。发现它在阴凉干燥的叶子中含量为 0.52% (w/w)，在加工提取物中含量为 5.02% (w/w)，在 Zandu Papaya 片剂（商业配方）中含量为 0.04% (w/w)。图形概要