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Updated: May 9, 2026

Untargeted Metabolomics from Biological Sources Using Ultraperformance Liquid Chromatography-High Resolution Mass Spectrometry (UPLC-HRMS)
Published on: May 20, 2013
Citron and lemon under the lens of HR-MAS NMR spectroscopy
Adele Mucci1, Francesca Parenti, Valeria Righi
1Dipartimento di Scienze Chimiche e Geologiche, Università di Modena e Reggio Emilia, Via G. Campi 183, 41125 Modena, Italy. adele.mucci@unimore.it
Abstract:
High Resolution Magic Angle Spinning (HR-MAS) is an NMR technique that can be applied to semi-solid samples. Flavedo, albedo, pulp, seeds, and oil gland content of lemon and citron were studied through HR-MAS NMR spectroscopy, which was used directly on intact tissue specimens without any physicochemical manipulation. HR-MAS NMR proved to be a very suitable technique for detecting terpenes, sugars, organic acids, aminoacids and osmolites. It is valuable in observing changes in sugars, principal organic acids (mainly citric and malic) and ethanol contents of pulp specimens and this strongly point to its use to follow fruit ripening, or commercial assessment of fruit maturity. HR-MAS NMR was also used to derive the molar percentage of fatty acid components of lipids in seeds, which can change depending on the Citrus species and varieties. Finally, this technique was employed to elucidate the metabolic profile of mold flavedo.
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