• Bulletin of the Korean Chemical Society
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• v.34 no.12
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• pp.3817-3824
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• 2013

Various separation modes in HPLC, such as anion exchange (AE), reversed-phase (RP), and affinity (AF) chromatography were examined for the separation of selenium species in human blood serum and urine. While RP- and AE-HPLC were mainly used for the separation of small molecular selenium species, double column AF-HPLC achieved the separation of selenoproteins in blood serum efficiently. Further, the effluent of AF-HPLC was enzymatically hydrolyzed and then analyzed with RP HPLC for selenoamino acid study. The versatility of the hybrid technique makes the in-depth study of selenium species possible. For quantification, post column isotope dilution (ID) with $^{78}Se$ spike was performed. ORC ICP/MS (octapole reaction cell inductively coupled plasma/mass spectrometry) was used with 4 mL $min^{-1}$ Hydrogen as reaction gas. In urine sample, inorganic selenium and SeCys were identified. In blood serum, selenoproteins GPx, SelP and SeAlb were detected and quantified. The concentration for GPx, SelP and SeAlb was $22.8{\pm}3.4\;ng\;g^{-1}$, $45.2{\pm}1.7\;ng\;g^{-1}$, and $16.1{\pm}2.2\;ng\;g^{-1}$, respectively when $^{80}Se/^{78}Se$ was used. The sum of these selenoproteins ($84.1{\pm}4.4\;ng\;g^{-1}$) agrees well with the total selenium concentration measured with the ID method of $87.0{\pm}3.0\;ng\;g^{-1}$. Enzymatic hydrolysis of each selenium proteins revealed that SeCys is the major amino acid for all three proteins and SeMet is contained in SeAlb only.

• Korean Chemical Engineering Research
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• v.56 no.3
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• pp.376-380
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• 2018

The astaxanthin recovery efficiencies were compared in acetonitrile, acetone, methanol, dichloromethane : methanol (1:3, v/v) and ethylacetate : ethanol (1:1, v/v) as a extraction solvent after the grinding of the H. pluvialis cells. The astaxanthin extraction yield in acetone was 1.13~1.29 times higher than other extraction solvents. It was also found that 96.7% of astaxanthin accumulated in H. pluvialis could be recovered by a single extraction. Since astaxanthin exists mainly as astaxanthin esters in H. pluvialis, a gradient reversed-phase HPLC analysis was carried out for the separation of astaxanthin esters from the extracts of H. pluvialis. Among the astaxanthin inside the H. pluvialis cell, free astaxanthin was 45.9% and astaxanthin esters were the rest.

• The Korean Journal of Food And Nutrition
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• v.20 no.4
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• pp.440-449
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• 2007

The purpose of this study was to examine the effects of taurine supplementation on serum lipidperoxide(TBARS), a risk factor for cardiovascular disease. The subjects were 22 healthy middle-aged women(33 to 54 years). Serum lipids, thiobarbituric acid reactive substances(TBARS), and plasma taurine levels were measured before and after supplying 3 g of taurine per day for 4 weeks. Plasma taurine was analyzed by Dabsyl-Cl(4-dimethylamino azobenzen-4-sulfonyl-chloride) derivatization and reversed-phase HPLC. Serum TBARS was measured by the Yagi method. Daily dietary taurine intake was calculated by food frequency questionnaire method. The weight and height means of the 22 subjects were $57.9{\pm}5.2$ kg and $159.2{\pm}5.2$ cm, respectively. Their percent body fat and waist/hip ratio(WHR) were 26.8% and 0.84, respectively, which were slightly higher than the average for middle-aged Korean women. Serum TC, TG and LDL-C levels tended to decrease after taurine supplementation, but HDL-C was not changed. A positive correlation between plasma taurine and HDL-C was shown after taurine supplementation. The serum TBARS concentration was significantly decreased from $5.05{\pm}0.84nmol/d{\ell}$ to $4.17{\pm}0.64nmol/d{\ell}$ after taking taurine(p<0.01), and the plasma taurine concentration was significantly increased from $63.7{\pm}14.2{\mu}mol/{\ell}$ to $73.8{\pm}16.6{\mu}mol/{\ell}$ after taurine supplementation(p<0.05). The average dietary intake of taurine was $178.5{\pm}50.4$ mg/day, which is similar to the average daily taurine intake of Korean women. In conclusion, taurine is an effective nutrient that antagonizes TBARS levels. Therefore, this study suggests that a sufficient taurine intake may be an effective way to prevent cardiovascular disease such as atherosclerosis.

• Food Science of Animal Resources
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• v.21 no.4
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• pp.367-373
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• 2001

Glycoproteins PAS-6(50 kDa) and -7(47 kDa) from the bovine milk fat globule membrane share a common protein core but differ in their carbohydrate moiety. We have analyzed and proposed the structures of the N-linked sugar chains of PAS-7 by Oxford Glyco System(OGS) RAAM2000. The N-linked sugar chains were liberated from PAS-7 by hydrazinolysis and, after modifying the reducing ends with 2-aminobenzamide(2-AB), were separated into one neutral(7N, 55%) and two acidic(7M, mono-, 43%; 7D, di-, 2%) sugar chain groups. 7N was finally separated into 5 chains(a, b, c, d, and e), respectively. The structure of this 2AB-neutral sugar chain was determined by sugar analysis, exoglycosidase digestion with OGS glycosidase Kit and OGS RAAM2000 system. The results show that fraction e was the same of reported 7N1A, the biantennary complex type with a fucose on reducing end and two N-acetyllactosamine branch on non-reducing end. Therefore, it was proved that OGS RAAM2000 method is in conformity with conventional analysis of sugar chain structure from bovine PAS-7.

• Bulletin of the Korean Chemical Society
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• v.35 no.7
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• pp.1956-1964
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• 2014

To provide the scientific corroboration of the traditional uses of Akebia quinata (Thunb.) Decne., a detailed analytical examination of A. quinata stems was carried out using a reversed-phase high performance liquid chromatography (RP-HPLC) method coupled to photodiode array detector (PDA) for the simultaneous determination of four phenolic substances; cuneataside D (1), 2-(3,4-dihydroxyphenyl)ethyl-O-${\beta}$-D-glucopyranoside (2), 3-caffeoylquinic acid (3) and calceolarioside B (4). Particular attention was focused on the main compound, 3-caffeoylquinic acid (3), which has a range of biological functions. In addition, 2-(3,4-dihydroxyphenyl)ethyl-O-${\beta}$-D-glucopyranoside (2) was considered as a discernible marker of A. quinata from its easy confuse plants. The contents of compounds 2 and 3 ranged from 0.72 to 2.68 mg/g and from 1.66 to 5.64 mg/g, respectively. The validation data indicated that this HPLC/PDA assay was used successfully to quantify the four phenolic compounds in A. quinata from different locations using relatively simple conditions and procedures. The pattern-recognition analysis data from 53 samples classified them into two groups, allowing discrimination between A. quinata and comparable herbs. The results suggest that the established HPLC/PDA method is suitable for quantitation and pattern-recognition analyses for a quality evaluation of this medicinal herb.

• Archives of Pharmacal Research
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• v.29 no.12
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• pp.1164-1170
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• 2006

A triptolide-lysozyme (TP-LZM) conjugate was synthesized to achieve renal specific delivery and to reduce the side effects of triptolide. Triptolide was coupled to lysozyme through succinic via an ester bond with an average coupling degree of 1 mol triptolide per 1 mol lysozyme. The lysozyme can specifically accumulate in the proximal tubular cells of the kidney, making it a potential carrier for targeting drugs to the kidney. The structure of triptolide succinate (TPS) was confirmed by IR, $^{1}H-NMR$, MS and UV. The concentrations of triptolide in various samples were determined by reversed-phase high-performance liquid chromatography (HPLC). In this study, the physicochemical and stability profiles of TP-LZM under various conditions were investgated the stability and releasing profiles of triptolide-lysozyme (TP-LZM) under various conditions. In vitro release trails showed triptolide-lysozyme was relatively stable in plasma (less than 30% of free triptolide released) and could release triptolide quickly in lysosome (more than 80% of free triptolide released) at $37^{\circ}C$ for 24 h. In addition, the biological activities of the conjugate on normal rat kidney proximal tubular cells (NRK52E) were also tested. The conjugate can effectively reduce NO production in the medium of NRK52E induced by lipopolysaccharide (LPS) but with much lower toxicity. These studies suggest the possibility to promote curative effect and reduce its extra-renal toxicity of triptolide by TP-LZM conjugate.

• Journal of Ginseng Research
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• v.42 no.1
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• pp.21-26
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• 2018

Background: Furosine (${\varepsilon}$-N-2-furoylmethyl-L-lysine, FML) is an amino acid derivative, which is considered to be an important indicator of the extent of damage (deteriorating the quality of amino acid and proteins due to a blockage of lysine and a decrease in the digestibility of proteins) during the early stages of the Maillard reaction. In addition, FML has been proven to be harmful because it is closely related to a variety of diseases such as diabetes. The qualitative analysis of FML in fresh and processed ginsengs was confirmed using HPLC-MS. Methods: An ion-pair reversed-phase LC method was used for the quantitative analysis of FML in various ginseng samples. Results: The contents of FML in the ginseng samples were 3.35-42.28 g/kg protein. The lowest value was observed in the freshly collected ginseng samples, and the highest value was found in the black ginseng concentrate. Heat treatment and honey addition significantly increased the FML content from 3.35 g/kg protein to 42.28 g/kg protein. Conclusion: These results indicate that FML is a promising indicator to estimate the heat treatment degree and honey addition level during the manufacture of ginseng products. The FML content is also an important parameter to identity the quality of ginseng products. In addition, the generation and regulation of potentially harmful Maillard reaction products-FML in ginseng processing was also investigated, providing a solid theoretical foundation and valuable reference for safe ginseng processing.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.15 no.2
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• pp.59-64
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• 2015

Purpose: Lactate has two optical isomers, L-lactate and D-lactate. In human L-lactate is the most abundant enantiomer of lactate. As plasma and urinary levels of L-lactate is associated with inherited metabolic disorders in general, D-lactate have been linked to the presence of diabetes and inflammatory bowel disease. Previously developed techniques have shown several limitations to further evaluate D-lactate as a biomarker for this condition. In this paper, we describe a highly sensitive, specific and fast liquid chromatography tandem mass spectrometry (LC-MS/MS) method for the analysis of D-, L-lactate in urine. Methods: D- and L-lactate were quantified using high performance liquid chromatography tandem mass spectrometry (LC-MS/MS) with labelled internal standard. Samples were derivatized with (+)-O,O'-diacety-L-tartaric anhydride (DATAN) and seperated on a Poroshell 120 EC-C18 column. Results: Quantitative analysis of D-, and L-lactate was achieved successfully. Calibration curves were linear (r>0.999) over $0.5-100{\mu}g/mL$. Stabilities for samples were within the 10% varation. Inter- and Intra-day assay variations were below 10%. Conclusion: The presented method proved to be suitable for the quantitation of D- and L-lactate and opens the possibility to explore the use of D-lactate as a biomarker.

• Korean journal of food and cookery science
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• v.11 no.3
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• pp.303-308
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• 1995

When we prepared the cooked namul, bugak and kimchi by the leaves of Cedrela sinensis, the changes of quercitrin which was isolated from the leaves of this plant in each preparations were analysed by HPLC. Separation by reversed phase chromatography on u-Bondapak C/Sub 18/ column was achieved by isocratic elution with THF-dioxane-MeOH-HOAc-5％ H/Sub 3/PO/Sub 4/-H/Sub 2/O (145: 125:50:20:2:658). When Kimchi was stored at 5$^{\circ}C$ for 20 days, the content of quercitrin in the methanol extract of Kimchi was 7.21％ and Kimchi at 20$^{\circ}C$ was reduced by 5.78％ (w/w). Contents of quercitrin in the leaves of Cedrela sinensis kimchi obsered to be gradually decreased during storage at 5$^{\circ}C$ and 20$^{\circ}C$. Contents of quercitrin of stored kimchi at 5$^{\circ}C$ was higher than that stored at 20$^{\circ}C$. The contents of quercitrin in Namul and Bugak were 13.06 and 5.03％ (w/w), respectively, which were lower than control.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.12
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• pp.4937-4944
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• 2015

MicroRNAs (miRNAs) are emerging as critical regulators in carcinogenesis and tumor progression. Recently, miR-99a has been reported as a tumor suppressor gene in various human cancers, but its functions in the context of anaplastic thyroid cancer (ATC) remain unknown. In this study, we reported that miR-99a was commonly downregulated in ATC tissue specimens and cell lines with important functional consequences. Overexpression of miR-99a not only dramatically reduced ATC cell viability by inducing cell apoptosis and accumulation of cells at G1 phase, but also inhibited tumorigenicity in vivo. We then screened and identified a novel miR-99a target, mammalian target of rapamycin (mTOR), and it was further confirmed by luciferase assay. Up-regulation of miR-99a would markedly reduce the expression of mTOR and its downstream phosphorylated proteins (p-4E-BP1 and p-S6K1). Similar to restoring miR-99a expression, mTOR down-regulation suppressed cell viability and increased cell apoptosis, whereas restoration of mTOR expression significantly reversed the miR-99a antitumor activity and the inhibition of mTOR/p-4E-BP1/p-S6K1 signal pathway profile. In clinical specimens and cell lines, mTOR was commonly overexpressed and its protein levels were statistically inversely correlated with miR-99a expression. Taken together, our results demonstrated for the first time that miR-99a functions as a tumor suppressor and plays an important role in inhibiting the tumorigenesis through targeting the mTOR/p-4E-BP1/p-S6K1 pathway in ATC cells. Given these, miR-99a may serve as a novel prognostic/diagnostic and therapeutic target for treating ATC.