Nishizaki Y1, Tada A, Ishizuki K, Ito Y, Onoda A, Sugimoto N, Akiyama H.
Shokuhin Eiseigaku Zasshi. 2015;56(5):185-93. doi: 10.3358/shokueishi.56.185.A novel HPLC-based method employing molar absorption coefficient ratios to 4-hydroxybenzoic acid (4HBA) was developed for the determination of quassin and neoquassin in Jamaica quassia extract, which is used as a food additive in Japan. Based on comparisons of quantitative NMR (qNMR) spectra and HPLC chromatograms of an artificial mixture of quassin, neoquassin, and 4HBA, the molar absorption coefficient ratios of quassin and neoquassin to 4HBA were determined as 0. Read More