노로바이러스는 전세계적으로 모든 연령에게 급성 장염을 일으키는 주요 원인체이다. 본 연구는 국내 식품업계의 식품종사자를 대상으로 무증상 노로바이러스 감염의 유행성을 조사하였다. 2,729명의 식품종사자에서 29명 (1.06%)이 무증상 노로바이러스로 확인되었고 이 중 5명 (17.24%)은 노로바이러스 GI 양성이었고 24명(82.76%)은 노로바이러스 GII 양성이었다. 특히 유전자 염기서열 분석과 계통 분석에서 GII-4 유전자형이 가장 유행성이 높은 것으로 나타났으며 많은 수의 무증상 식품종사자는 노로바이러스 GII-4 에 감염되어있었다. 따라서 본 연구의 결과는 무증상 식품종사자가 노로바이러스 감염에 잠재적인 전파 원인일 가능성이 있음을 보여준다. 또한 이러한 결과는 노로바이러스 예방에 대한 식품업체의 교육의 필요성을 강조한다. 무증상 노로바이러스 감염에 더 많은 주 의를 기울여야 할 것이다.

Multiple starters consisting of two Bacillus amyloliquefaciens strains (MJ1-4 and EMD17), Pichiafarinosa SY80, and Rhizopus oryzae were used for Doenjang making. Bacillus strains were selected based on their abilities to inhibit toxinogenic fungi and Bacillus cereus, fibrinolytic activity, and their ability to confer good flavor to Cheonggukjang. P. farinosa SY80 and R. oryzae, previously isolated from soy sauce, were selected because they were not inhibited by two bacilli. Doenjang was prepared by inoculation of multiple starters (A1 Doenjang). Control Doenjang was prepared by inoculation of B. subtilis KACC 16750 (Natto strain) and Aspergillus oryzae KCCM 60166 (A2 Doenjang). Another control (A3 Doenjang) was prepared by inoculation of microorganisms present in rice straw. Doenjang samples were fermented for 70 days at 20℃. pH of 3 samples decreased from the initial value of 6.4 to 5.8~6.0 and titratable acidity (TA) increased from 0.6 to 1.1~1.3. The amount of amino-type nitrogen increased during fermentation. There were slight differences in moisture, crude-protein, and crude-fat contents after 70 days. Contamination of fungi was observed only in A3 Doenjang and B. cereus was not detected from all 3 samples. A1 Doenjang showed the highest fibrinolytic activity and A2 Doenjang the second. These results indicate that Doenjang made with carefully selected starters was functionally improved and microbially more safe.

As a continuation of a previous work by Park et al. (2006), we have developed a two-element radio interferometer that can measure both the phase and amplitude of a visibility function. Two small radio telescopes with diameters of 2.3 m are used as before, but this time an external reference oscillator is shared by the two telescopes so that the local oscillator frequencies are identical. We do not use a hardware correlator; instead we record signals from the two telescopes onto a PC and then perform software correlation. Complex visibilities are obtained toward the sun at λ=21cm for 24 baselines with the use of the earth rotation and positional changes of one element, where the maximum baseline length projected onto UV plane is ~90λ As expected, the visibility amplitude decreases with the baseline length, while the phase is almost constant. The image obtained by the Fourier transformation of the visibility function nicely delineates the sun, which is barely resolved due to the limited baseline length. The experiment demonstrates that this system can be used as a "toy" interferometer at least for the education of (under)graduate students.

Alcoholic fatty liver disorder has become a frequent health concern worldwide. To investigate the effects of Brassica oleracea (B. oleracea) sprout extract (BOE), the present study was designed with alcoholic fatty liver in the rat. Initially, the effects of BOE on liver parameters were examined. Male rats were divided into five groups. The normal control group was fed the normal diet, and the BOE group was fed the high fat diet and ethanol with/without BOE for 4 weeks. After 4 weeks feeding period, rats were sacrificed and their livers and blood were used for fatty liver-related biomarkers analyses. As a result, BOE ameliorated fatty liver-related enzymes profiles in liver tissues and also reduced blood alcohol concentration in rat model. We demonstrated that BOE protected the high fat diet and alcohol-induced fatty liver in rat model. Furthermore, BOE increased detoxificative abilities against alcohol.

Background : Although ginseng has various bioactive compounds in it, there is lack of study on the variations of bioactive compounds in ginseng according to the cultivation soil and the applied fertilizer types (or amount). Therefore, this study aims to examine the variations of 37 fatty acids (FA) and 8 vitamin E (Vit-E) vitamers in 6-year-old ginseng root cultivated in different soil types with different fertilizers regimes. Methods and Results : The profiling of 37 FAs and 8 Vit-E vitamers in 6-year-old ginseng roots was measured by gas chromatography coupled with a flame ionization detector, and then these results were statistically analyzed with chemometrics. The FA and Vit-E content in ginseng roots varied significantly with respect to soil cultivation conditions due to organic fertilizer types and amounts used. Unsaturated FA in ginseng is approximately 2.7 fold higher than the saturated FA. Linoleic, palmitic, and oleic acids were the most abundant FAs found in the ginseng roots. Also, the major Vit-E vitamer found in ginseng root is α-tocopherol. In particular, the application of rice straw compost or food waste fertilizer was increased to create nutritionally desirable FAs and bioactive Vit-E in ginseng root. In addition, phytonutrient profiling coupled with chemometrics can be used to discriminate the cultivation conditions of ginseng. Conclusion : This study extends our understanding about the variations of FA and Vit-E in ginseng root depending on cultivation conditions. Hence, these results can be useful as basic information for reliable ginseng production containing high amounts of phytonutrients in a paddy-converted field.

Background : The geographical origin of Panax ginseng Meyer, a valuable medicinal plant, is important to both ginseng producers and consumers in the context of economic profit and human health benefits. We therefore aimed to discriminate between the cultivation regions of ginseng using the stable isotope ratios of C, N, O, and S, which are abundant bio-elements in living organisms. Methods and Results : The C, N, O, and S stable isotope ratios were measured by isotope ratio mass spectrometer, and then these isotope ratios profiling was statistically analyzed with chemometrics. The various isotope ratios found in Panax ginseng roots were significantly influenced by region, cultivar, and the interactions between these two factors (P ≤ 0.0002). In particular, δ18O was lower in ginseng roots grown at high altitudes (r = −0.47), while δ34S was higher in ginseng roots grown close to coastal areas (r = −0.48). Chemometric results provided discrimination between the majorities of different cultivation regions. Conclusion : Our case study extends the understanding about the variation of C, N, O, and S stable isotope ratios in ginseng root depending on cultivation region. Hence, the analysis of stable isotope ratios is a suitable tool for discrimination between the regional origins of ginseng samples from Korea, with potential application to other countries.

Background : Corrosion is one of the most devastating problems faced by most industries. Mild steel has played a vital role in various fields due to the excellent mechanical properties of mild steel such as low density, high strength-to-weight ratios, good environmental stability, high thermal conductivity, and corrosion resistance. Methods and Results : The total phenolic contents (TPC) and total flavonoid contents (TFC) of the methanolic extract of C. grandiflora and R. verniciflua leaf have been examined, and its corrosion inhibition performance was investigated by weight loss and electrochemical impedance spectroscopy (EIS) and polarization measurements. The surface morphology of mild steel was analyzed by scanning electron microscopy (SEM) equipped with energy dispersive X-ray spectroscopy (EDX) and by atomic force microscopy (AFM). The percentage composition of polyphenolic compounds was found to be higher in C. grandiflora and R. verniciflua plant extracts, and it was proved to be a superior, eco-friendly, and anti-corrosive inhibitor for mild steel in 1M of H2SO4. The Tafel polarization studies indicate that the plant extract is a mixed-type inhibitor. Scanning electron microscopy/energy -dispersive X-ray spectroscopy (SEM-EDS), and atomic force microscopy (AFM) studies confirmed the formation of a protective film on the metal surface. The corrosion inhibition of the C. grandiflora and R. verniciflua plant extracts was characterized by Fourier transform infrared (FT-IR), UV-visible spectra, and wide-angle X-ray diffraction (XRD) studies; these show the strong interaction between the metal surface and the inhibitor. Conclusion : The methanolic extract was prepared the two different plants like C. grandiflora, and R. verniciflua was studied the corrosion inhibition on the mild steel specimen in acidic medium through various methods involving weight loss measurements, EIS, and potentiodynamic polarization. The results shows that the C. grandiflora, and R. verniciflua plant extracts illustrate an effective corrosion inhibitor for mild steel with good anticorrosion properties in acidic environmen

Background : The natural stable isotope ratio of common bio-elements like carbon (C), nitrogen (N), oxygen (O), or sulfur (S) varies with diverse isotope fractionation processes in nature. Therefore, measuring the variation of these stable isotope ratios in ginseng roots can be a feasible tool to discriminate the geographical origins of ginseng in Korea. Methods and Results : The 3-year-old six Korean ginseng cultivars were cultivated at the five regions in Korea, and then used for measuring the stable isotope ratios of C, N, O, and S by isotope ratio mass spectrometry (IRMS). The mean C, N, O, and S stable isotope ratio values in the ginseng roots significantly differed according to the cultivation regions (p < 0.05). However, these isotope ratios in ginseng roots had relatively weak discriminative power against to the ginseng cultivars at each cultivation region. The interaction of the cultivation region and ginseng cultivar type also significantly affected to the C, N, O, and S stable isotope ratio in ginseng roots (p < 0.0001). The two-dimensional plots associated with the N stable isotope ratio can effectively separate the ginseng roots in Jinan compared to those in the other regions. The partial least squares-discriminant analysis showed more significant separation between ginseng geographical origins compared to the principal component analysis. Conclusion : Our findings improve our understanding of how the isotope composition of ginseng roots varies with respect to cultivation regions and cultivars, and suggest that the analysis of the stable isotope ratios combined with chemometrics can be used as a feasible tool to discriminate geographical origin of ginseng in Korea.