Discrimination of ginseng cultivation regions using light stable isotope analysis.

Korean ginseng is considered to be a precious health food in Asia. Today, thieves frequently compromise ginseng farms by pervasive theft. Thus, studies regarding the characteristics of ginseng according to growth region are required in order to deter ginseng thieves and prevent theft. In this study, 6 regions were selected on the basis of Korea regional criteria (si, gun, gu), and two ginseng-farms were randomly selected from each of the 6 regions. Then 4-6 samples of ginseng were acquired from each ginseng farm. The stable isotopic compositions of H, O, C, and N of the collected ginseng samples were analyzed. As a result, differences in the hydrogen isotope ratios could be used to distinguish regional differences, and differences in the nitrogen isotope ratios yielded characteristic information regarding the farms from which the samples were obtained. Thus, stable isotope values could be used to differentiate samples according to regional differences. Therefore, stable isotope analysis serves as a powerful tool to discriminate the regional origin of Korean ginseng samples from across Korea.

Discrimination between ginseng from Korea and China by light stable isotope analysis.

Ginseng is a health food and traditional medicine highly valued in Asia. Ginseng from certain origins is higher valued than from other origins, so that a reliable method for differentiation of geographical origin is important for the economics of ginseng production. To discriminate between ginseng samples from South Korea and PR China, 29 samples have been analyzed for the isotopic composition of the elements H, C and N. The results showed δ(2)H values between -94 and -79‰, for δ(13)C -27.9 to -23.7‰ and for δ(15)N 1.3-5.4‰ for Chinese ginseng. Korean ginseng gave δ(2)H ratios between -91 and -69‰, δ(13)C ratios between -31.2 and -22.4‰ and δ(15)N ratios between -2.4 and +7‰. Despite the overlap between the values for individual isotopes, a combination of the isotope systems gave a reasonable differentiation between the two geographic origins. Especially the statistically significant difference in δ(2)H ratios facilitated the differentiation between Korean and Chinese ginseng samples.

Immunochromatographic analysis of hippuric acid in urine.

Toluene, a clear, colorless liquid with a distinctive smell, is the most commonly used industrial organic solvent. The adverse effects of chronic toluene exposure have been reported. The abuse of volatile substances is practiced mainly by adolescents and young adults. Chronic toluene abuse causes permanent changes in brain structure correlated with brain dysfunction; therefore, it is important to monitor the level of toluene exposure to prevent neurological damages. In this study, immunochromatographic analysis was performed to measure a level of the exposed toluene easily and accurately in urine. Inhaled toluene is metabolized to hippuric acid (HA) in the liver and secreted in urine. Therefore, the monoclonal antibodies against HA were generated and characterized by indirect competitive ELISA. The sensitivity was then monitored in order to adjust the cutoff concentration to 2 mg of HA/mL of urine. Using these monoclonal antibodies as raw materials, the immunochromatographic device was manufactured with the lateral flow system. The clinical studies were performed with suspected users' urine samples, and the results were confirmed by high-performance liquid chromatography.