Identification and estimation of a novel fluorescent compound in nutmeg

A novel fluorescent naphthaquinone derivative was isolated from the hexane extract of commercial nutmeg (Myristica fragrance). The compound was identified as 2-methyl-1,4,4a,8a-tetrahydro-endo-1,4-methanonaphthalene-5,8-dione from its NMR, IR and mass spectral data. Absence of this compound in green nutmeg suggested its formation during sun drying. Exposure of the spice to gamma radiation (0.5–10 kGy) resulted in an increase in its content with dose further signifying its formation via a photochemical pathway. Quantification of this increase by thin layer chromatography (TLC)–densitometry as a means of rapid detection of gamma-irradiated nutmeg is suggested. A dose-dependent increase in the presently identified compound suggests a possibility of monitoring its content in the processed product as a means of measuring absorbed dose.