[Analysis of the extraction of red pellicle of walnut (Juglans regia L.) by ultraviolet-visible spectra and HPLC-ESI-MS(n)].

The extraction of the red pellicle of walnut (Juglans regia L.) was analyzed by UV-visible spectra and HPLC-ESI-MS(n) (high-performance-liquid-chromatography coupled with electrospray ionization mass spectrometry). The extraction in ethanol-HCl showed two absorption peaks at 560 and 591 nm respectively in the UV-Vis spectrum; after purified by lead acetate and thin-layer-chromatography, the extraction in ethanol-HCl showed 4 absorption peaks at 340, 370, 552 and 585 nm respectively. These results testified that the anthocyanin was in the extraction. Six molecular ion peaks (m/z) occurred on MS: 301, 481, 633, 783, 785 and 950, which was identified as ellagic acid, Hexahydroxydiphenoyl(HHDP)-glucose, Galloyl-HHDP-glucose, Di-HHDP-glucose, Di-Galloyl-HHDP-glucose, and HHDP-Valoneoyl-glucose respectively.