• Bulletin of Food Technology
• /
• v.10 no.1
• /
• pp.94-101
• /
• 1997

NIR(근적외) 분광분석법이 녹차의 원산국을 판별하는데 이용할 수 있는지를 알아보기 위하여 분쇄한 47종의 한국산 및 일본산 녹차에 대하여 NIR 분석을 실시한 후, 그 분광 데이터에 대하여 principal component analysis(주성분 분석 )와 canonical variate analysis(정준판별분석)을 실시하였다. 15개의 주성분과 1100~2500nm에서의 first derivative log(1/R) 데이터를 이용할 경우, 제1 및 제2 정준판별함수는 한국산 녹차 및 일본산 녹차를 판별하는데 가장 효과적이었다. 사용된 canonical variate analysis는 녹차 시료를 97.87%의 정확도로 그 지리적 출처를 판별하였다. 한편 first derivative log(1/R) spectra상의 파장범위 1674~1686, 1950~1992, 2014~2030및 2118~2158 nm에서 일본산 녹차와 3종의 한국산 녹차 그룹간에 현저한 차이가 발견되었다. 이 차이는 polyphenols, caffeine 및 amino acids와 같은 녹차의 주요성분과 관련되어 있지 않으며 주로 지리적 출처상의 차이에 기인한 것으로 판단되었다.

• Microbiology and Biotechnology Letters
• /
• v.24 no.5
• /
• pp.591-596
• /
• 1996

In the course of screening lipid peroxidation inhibitor from basidiomycetes, a mushroom, which was collected at O-Dae mountain in Kangweon- Do, was found to have active compound. The mushroom was identified as Polyzellus multiplex, which belongs to Aphylloporalles Thelephoraceae, on the basis of macroscopic and microscopic characteristics of the fruiting body. The methanol extract of fruiting body was extracted with benzene and ethylacetate, sequentially. By using various kinds of chromatographies, PM1, and PM2 and PM3, were purified from the ethylacetate extract and the benzene extract, respectively. Color reaction and analyses of IR, UV, and NMR spectra indicated that PM1 was a derivative of thelephoric acid, and PM2 and PM3 were linoleic acid and oleic acid, respectively. IC$_{50}$ of PM1 for inhibition of lipid peroxidation was 1.96 ppm and LD$_{50}$ was 500 mg/kg.

• Food Science and Biotechnology
• /
• v.17 no.4
• /
• pp.870-872
• /
• 2008

Barley $\beta$-glucan was subjected to chemical modification and the anticoagulant activity of the derivative was investigated. The barley $\beta$-glucan was successfully sulfated, showing the degree of substitution calculated by elemental analysis of 0.40. In addition, the Fourier transform infrared (FT-IR) spectra of the derivative confirmed the sulfation, which generated two new absorption bands at 1,250/cm (S=O) and 810/cm (C-O-S) compared to the native. Specially, the anticoagulant activity of barley $\beta$-glucan was created by sulfation, which increased in a concentration-dependent manner. This result demonstrated that the incorporation of sulfate groups into the $\beta$-glucan structure added a blood clotting prevention effect.

• Bulletin of the Korean Chemical Society
• /
• v.20 no.8
• /
• pp.905-909
• /
• 1999

Reaction of tetrahomodioxa p-phenylcalix[4]arene with ethyl bromoacetate and potassium carbonate in ace-tone leads to the title tetra ester derivative, 7,13,21,27-tetra-phenyl-29,30,31,32 -tetrakis(ethoxycarbonyl)meth-oxy-2,3,16,17-tetrahomo-3,17-dioxacalix[4]arene, its structure was determined by NMR spectra as 1,4-alternate conformation. The molecular structure has been solved by X-ray diffraction methods. The molecule has a conformation with pseudo center of symmetry. The benzene ring A is up, ring C is down, B and D rings are flat with respect to the plane of the macrocyclic ring.

• Analytical Science and Technology
• /
• v.12 no.5
• /
• pp.375-381
• /
• 1999

Near infrared spectrophotometry(NIR) was developed as a non-invasive determination of blood alcohol. The first pure alcohol/water samples were prepared with ethanol concentration from 0.01 to 0.1%(w/w). Analysis of the second-derivative data was accomplished with multilinear regression(MLR). The standard error of calibration(SEC) of ethanol in ethanol/water solutions was approximately 0.0039%. The calibration models were established from the blood alcohol spectra by MLR and PLSR analysis. The best calibration was built with the second-derivative spectra of 2266 and 2326 nm by MLR. Second-derivative spectra in the spectral ranges of 1100~1340, 1500~1796 and 2064~2300 nm with four PLSR factors provided the standard error of prediction(SEP) of 0.030%(w/w). These results indicate that NIR may be applied for a fast non-invasive determination of alcohol in the blood.

• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.30 no.2
• /
• pp.167-172
• /
• 2004

In the human skin, vitamin C (L -ascorbic acid) that is well known as the activated materials has effects that is skin anti-aging and wrinkle repair by giving impetus to collagen biosynthesis and anti-oxidation, and that is the sun screen, a wound recovering, inhibition melanogenesis and so on. In spite of its effects, vitamin C has the defects of the skin stimulation and easily oxidized instability by water, air, heat and light. For solving their matters, many investigation is advanced and its results are synthesized the various vitamin C derivatives. And yet they have not solved the unstable property of vitamin C and were still insufficient for the comparing with the effect of the pure vitamin C itself. In this study, in order to prepare vitamin C derivative of being improved the stability and to apply vitamin C effect in the skin, we prepared new vitamin C derivative, phytosphingosine ascorbate, by using phytosphingosine, one of sphingolipids, which have a distinguished skin affinity. Phytosphingosine ascorbate can be prepared as the ionic bond between amine group (-NH$_2$) of phytosphingosine and hydroxy group (-OH) of vitamin C by way of the relatively simple reaction. So the structure and properties of the synthesized phytosphingosine ascorbate was confirmed the use of elemental analysis (C 58.3 : H 9.3 : N 2.8 : O 29.5), MALDI TOF-MS (Mw=492.58), Ultraviolet spectra (268.5nm), lH NMR, FT-IR spectra, thermal analysis (m.p=l54$^{\circ}C$), HPLC and so on. And we could confirm the anti-bacterial and anti-oxidation effects. Based on these results, we could confirm to prepare a new material that was expected of both effects of vitamin C and phytosphingosine and that is improved properties of vitamin C.

• Near Infrared Analysis
• /
• v.1 no.2
• /
• pp.21-27
• /
• 2000

Temperature-dependent changes in near-infrared (NIR) spectra have been measured for oleic acid, and nonanoic acid in the pure liquid state. Particular attention has been paid to the 5400-4800 cm$\^$-1/ region where a number of combination bands appear. The NIR spectra of oleic acid show that a band at 5303 cm$\^$-1/ increases with temperature while that at 5270 cm/sup-1/ decreases. It ha been found from their second derivative spectra that these spectral changes take place stepwisely with two break points at 30 and 53$\^{C}$, which correspond to the phase transition temperatures oleic acid reported previously. Principle component analysis (PCA) has been carried out for the NIR spectra of oleic acid in the 5400-4800 cm$\^$-1/ region measured over a temperature range of 15-80$\^{C}$. core plots of the first and second principal components (PCs) show that the NIR spectra are classified into three groups; the spectra measured in the temperature range of 15-30$\^{C}$, those in the range of 31-53$\^{C}$, and those in the range of 54-80$\^{C}$. These temperature ranges correspond to those for quasi-smectic liquid crystal, disordered liquid crystal, and isotropic liquid of oleic acid in the pure liquid state. In other words, PCA provides unambiguous evidence for the phase transitions. similar studies have been carried out for petroselinic acid and nonanoic acid in the pure liquid states, but they do not show any evidence for phase transitions.

• Environmental Analysis Health and Toxicology
• /
• v.15 no.1_2
• /
• pp.39-43
• /
• 2000

Linear alkyl sulfonates (LAS) constitute a large fraction of the surfactants used in cleaning processes in households, trade and industry Despite the industrial significance and the possible environmental impact of these compounds, the fast and inexpensive determination of LAS concentrations is still a difficult task. In this study, near infrared (NIR) spectroscopy which is a rapid spectroscopic analysis method compared with a traditional analytical method for the measurement of LAS concentration such as HPLC, GC and standard wet chemistry method. NIR spectra of LAS between 0.313 and 25.0% (w/v) in water were utilized to develop a calibration model. The best results (R ＝ 0.998, SEP ＝ 0.244% (w/v)) obtained by using partial least-squares regression with spectral data treatment and 2nd derivatization were comparable to the results (SEC ＝ 0.186% (w/v), SEP ＝ 0.206% (w/v)) obtained by using multiple linear least-squares regression (MLR). However, models based on derivative spectra have no significant advantage with MLR.

• Bulletin of the Korean Chemical Society
• /
• v.23 no.11
• /
• pp.1629-1634
• /
• 2002

Reaction of tetrahomodioxa p-phenylcalix[4]arene with alkyl halide and NaH in DMF leads to the title tetra-alkylated derivatives, 7,13,21,27-tetra-phenyl-29,30,31,32-tetraalkyloxy-2,3,16,17-tetrahomo-3,17-dioxacalix [4]arenes, their preferred conformations were determined by NMR spectra as C-1,2-alternate. The molecular structure of allyl derivative has been solved by X-ray diffraction methods. The molecules have a conformation with pseudo center of symmetry. The benzene ring A is up, ring C is down, B and D rings are flat with respect to the plane of the macrocyclic ring.

• Bulletin of the Korean Chemical Society
• /
• v.30 no.7
• /
• pp.1667-1670
• /
• 2009