Validation of HPLC Method for Quantifying 1,4-Naphthoquinone in Ethanol and Water Extracts of <i>Eleutherine bulbosa</i>

Abstract

Eleutherine bulbosa (E. bulbosa) is a traditional medicinal plant known to contain 1,4-naphthoquinone as the active  compound responsible for its pharmacological effects. Ensuring consistent pharmacological effects in pharmaceutical  preparations necessitates the quantitative measurement of the active compound content in the extract. This study aims  to establish a method for quantifying the levels of 1,4-naphthoquinone in both ethanol and water extracts of E. bulbosa and to determine the optimal levels in both extracts. The High-Performance Liquid Chromatography (HPLC) method was  employed to assess the 1,4-naphthoquinone levels. Method validation was conducted to evaluate the accuracy,  precision, linearity, and selectivity of the method. The validation results indicate that this method has met the standards,  with the linearity test yielding an “r” value of 0.9939, the selectivity test indicating selectivity at 3.507  minutes, the precision test resulting in a %RSD of 0.7159%, and the accuracy test showing a % recovery of 99.53%. These  method validation parameters satisfy the required criteria, affirming the reliability of the method employed. The  average levels of 1,4-naphthoquinone in the ethanol extract were determined to be 4.5797 ppm, while in the water  extract, it measured 3.2314 ppm. These findings imply that the ethanol extract contains a higher concentration of 1,4- naphthoquinone compared to the water extract. Consequently, it can be inferred that the HPLC method for quantifying  1,4- naphthoquinone levels is valid, and the ethanol extract is recommended as a superior raw material for the  development of traditional medicines due to its higher content of active compounds.