Physicochemical Properties of Selectively Oxidized 1-Monolaurin from 2,2,6,6-Tetramethyl-1-Piperidinyl Oxoammonium Ion/Sodium Hypochlorite-Mediated Reaction

摘要

The primary alcohol group of 1-monolaurin(1-ML)was selectively oxidized using 2,2,6,6-tetramethyl-1-piperidine oxoammonium ion/sodium hypochlorite(NaOCl)without NaBr at two different conditions.The selective oxidation occurred more efficiently at 35 °C and 32.2 mmol of NaOCl than at 25 °C and 18.7 mmol of NaOCl.Regioselective oxidation of the primary alcohol without oxidation of a secondary alcohol was confirmed by a chemical shift at 175 ppm and no resonance between 198 and 205 ppm in ~(13)C NMR and the presence of a peak at 1560-1570 cm~(-1)in IR spectra.The water solubility of oxidized 1-monolaurin(OML)was remarkably increased by 33.2 times as compared to that of 1-ML.Creaming velocities resulting from fat flocculation in a 0.2% level of OML and 1-ML were 0.16 and 1.13 mm/h,respectively,implying that OML showed higher efficiency and emulsion stability in preventing fat flocculation than 1-ML due to the selective oxidation of primary alcohol.