We tried to prepare nanocapsules encapsulating Ukon (Curcuma longa L.) extract using lecithin by the new mechanochemical method. With the combination of homogenization and microfluidization, nanocapsules including crucumin (NUE) were efficiently obtained from lecithin and Ukon extract. Under the optimal conditions, the resulting NUE were confirmed to be small unilamellar vesicles (SUV) with a diameter of approximately 114 nm by the observation of freeze fracture electron microscopy. In addition, the encapsulation efficiency for curcumin reached over 85%. On the treatment of simulated gastric and intestinal fluids, the NUE showed a 2-fold higher residual rate of curcumin, compared to the uncapsuled extract itself. The bioactivity of NUE was further examined for the suppressive effect on carbon tetrachloride (CCl₄)-induced liver injury using mice. Interestingly, the NUE orally administrated at a dose of 10 mg/kg as to the extract showed much higher suppressive effect on the serum AST and ALT levels, compared to the uncapsuled extract at a dose of 33 mg/kg. Moreover, we investigated the intestinal absorption of nanocapsules encapsulating only curcumin (NEC) on rat, aiming to clarify the suppressive effect by NUE. Interestingly, the plasma level of curcumin significantly increased after NEC were orally administrated compared to the control. From these results, the functions of food materials would be highly improved by nanocapsulation with the present mechanochemical method.

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Two diastereomeric complex ions of a chiral material (enantiopure) with an equivalent mixture of a deuterium labeled one enantiomer and an unlabeled another enantiomer are observed in a mass spectrum, and the chiral discrimination ability or enantiopurity of the chiral materials are evaluated quantitatively on the basis of the relative peak intensity of the complex ions. In this paper the methodology, the design of the chiral material for the method, and detection of chirality using mass spectrometry are described. The relative peak intensity of the complex ions of chiral crown ether derivatives with chiral ammonium ions in the fast atom bombardment mass spectrometry was in good agreement with the ratio of the association constants in solution. While, that in the electrospray ionization (ESI) mass spectrometry is depressed since the evaporation of the chiral materials containing the deuterium-labeled/unlabeled enantiomeric pair in the ESI process changes the relative concentration of the complex ions. However, the relative peak intensity in ESI mass spectrometry shows high reproducibility under the same measurement conditions. The deuterium-labeled/unlabeled enantiomer pair of a metal complex were used to evaluate the optical purity of a chiral carboxylic acid in ESI mass spectrometry.

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