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.