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The biological effects of black garlic are stronger than those of fresh garlic, but despite the increasing manufacture of black garlic products, no specifications for controlling their quality have been identified. The most commonly used biological marker of quality is S-allylcysteine (SAC), which is a core active compound in the aforementioned products. SAC content is typically determined using high-performance liquid chromatography with ultraviolet detection, but this method presents many problems because of its complex matrices. To determine the content of SAC in black garlic, this study established a sensitive and reproducible method grounded in ultrahigh- performance liquid chromatography coupled with tandem mass spectrometry. The instrument used is equipped with a triple quadrupole mass detector with an electrospray ionization source. The analysis involved solid-phase extraction using a strongly acidic cationic exchange agent, which enabled the direct examination of samples without the need for derivatization and the determination of SAC content in 5 min. The established method was fully validated in terms of linearity, sensitivity, precision, repeatability, and recovery and was successfully applied in characterizing the quality of some black garlic products manufactured in Vietnam. The proposed procedure exhibited high linearity (R2 = 0.9993) at a limit of detection of 0.25 ng/mL, which is lower than those of other assay techniques. The results indicated that various black garlic products have different SAC contents. This study may be useful in the development of standards for the quality of black garlic. [ABSTRACT FROM AUTHOR]

In the course of this investigation, a method for the characterization and differentiation of paper pulps was developed. After hydrolyzation of the papers and the respective raw pulps with trifluoroacetic acid, the hydrolyzates were analyzed with respect to their carbohydrate composition using ion exchange chromatography. The variations in carbohydrate composition mainly arise from the various hemicelluloses of the papers and pulps. The chromatographic results were then further processed using principal component analysis which allows correlating the various papers to different pulp materials. [ABSTRACT FROM AUTHOR]

Presents the author's accounts of the 2nd Conference on Ion Analysis in Berlin, Germany in February 2003. Analysis of small inorganic and organic ions; Determination of anions and cations; Description of the scientific program.