Determination of 5‐hydroxy oxindole by high performance liquid chromatography in Protaetia brevitarsis seulensis extracts

White‐spotted flower larvae (Protaetia brevitarsis seulensis; PBS) have recently been approved as a food ingredient in Korea. They confer an antithrombotic effect in addition to various nutrients, including protein, fat, and dietary fiber. However, a quantitative analytical method is still required for the analysis of medicinal foods or medicines containing the active ingredient (5‐hydroxy oxindole, 5‐HI). The HPLC method validated on PBS larvae was verified through parameters such as linearity, specificity, range, accuracy, precision, detection limit, and quantitation limit. All the parameters tested met these criteria and were applied to the successful detection of the extract in PBS larvae. This HPLC method to detect 5‐HI could be used as a validated assay in regulatory processes.