HR-MAS NMR metabolic profiling, furosine and (E)-10-hydroxy-2-decenoic acid for qualitative and geographical discrimination of royal jelly

Freshness and authenticity of Chinese and Italian royal jelly samples were investigated by means of HPLC determination of furosine and (E)-10-hydroxy-2-decenoic acid. In addition, High Resolution Magic Angle Spinning Nuclear Magnetic Resonance (HR-MAS NMR) spectroscopy was used to determine the metabolic profile of the same royal jelly samples. Water-soluble metabolites such as amino acids and sugars as well as fatty acids were identified in the same experiment. A combined approach including NMR analytical profile together with HPLC measured markers was used to discriminate between Italian and Chinese samples by means of Principal Component Analysis.