Lotte R and nter

Seoul, South Korea

Lotte R and nter

Seoul, South Korea
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Seo J.-H.,Seoul National University | Hwang J.-Y.,Seoul National University | Hwang J.-Y.,Amore Pacific | Seo S.-H.,Seoul National University | And 5 more authors.
Bioscience, Biotechnology and Biochemistry | Year: 2012

ω-Aminotransferase (ω-AT) is an important class of enzymes for the synthesis of chiral amines or β-amino acids. Family profile analysis was applied to screen putative ω-ATs from Mesorhizobium loti MAFF303099, a nitrogen fixation bacterium that has a larger number of ATs than other microorganisms. By family profile analysis, we selected 10 putative ω-ATs according to E-value. The functions of the putative ω-ATs were investigated by examining activities towards amines and/or β-amino acids. 10 putative proteins were found to have ω-AT activity with narrow or broad substrate specificity. Structure analysis using crystal structure of mll7127 and homology models of mll1632 and mll3663 indicated that the structures of active sites of the enzymes were very similar and highly conserved, but their substrate specificities appreared to be determined by residues positioned at the entrance region of the active site binding pockets.

Jung S.,Chungnam National University | Kim H.J.,Seoul National University | Park S.,Korea Advanced Institute of Science and Technology | In Yong H.,Seoul National University | And 4 more authors.
Meat Science | Year: 2015

We investigated the possible use of atmospheric pressure plasma-treated water (PTW) as a nitrite source in curing process. Emulsion-type sausages were manufactured with PTW, celery powder containing nitrite, and synthetic sodium nitrite at a concentration of nitrite ion 70mgkg-1. In terms of sausage quality, there were no noticeable effects of PTW on the total aerobic bacterial counts, color, and peroxide values of sausages compared with those of celery powder and sodium nitrite throughout 28days of storage at 4°C. Sausage with added PTW had lower concentrations of residual nitrite compared to those of added celery powder and sodium nitrite during the storage period (P<0.05). The sensory properties of PTW-treated and sodium nitrite-treated sausages were not different, whereas the sausage with added celery powder received the lowest scores in taste and acceptability. From the results, it is concluded that PTW can be used as a nitrite source equivalent to a natural curing agent. © 2015 Elsevier Ltd.

Jung S.,Chungnam National University | Lee K.H.,Korea University | Nam K.C.,Sunchon National University | Jeon H.J.,Lotte R and nter | And 2 more authors.
Korean Journal for Food Science of Animal Resources | Year: 2014

The objective of this study was to compare the characteristics that define the quality of Woorimatdag™ (WM, a certified meat-type commercial Korea indigenous chicken breed) and a commercial broiler breed (Ross, CB). Two hundred WM and 200 CB chickens that were 1-d-old and mixed sex were obtained from a commercial hatchery and randomly assigned to floor pens (20 chickens per pen, 3.0×2.0 m) and raised under the same environmental conditions. WM breast meat contained significantly higher crude protein and ash as well as lower crude fat than CB breast meat (p<0.05). WM breast meat had slightly higher alanine, histidine, isoleucine, and glycine as well as lower phenylalanine content than CB breast meat (p< 0.05), and the WM breast meat had a low ratio of unsaturated to saturated fatty acid composition (p<0.05). However, arachidonic acid composition was higher in the WM than the CB breast meat. In addition, the inosin-5'-monophosphate content was also higher in the WM compared with the CB breast (p<0.05). The WM breast meat had higher total collagen content compared with CB breast meat. WM soup taste received higher scores with regard to sensory evaluation compared with CB soup (p<0.05). From these results, we conclude that higher amount of protein and flavor precursors and lower amount of fat in the breast meat of WM could be attractive by consumer when compared with CB.

Lee L.-S.,Korea Food Research Institute | Park J.-D.,Korea Food Research Institute | Cha H.-S.,Korea Food Research Institute | Lee Y.-M.,Lotte R and nter | And 2 more authors.
Korean Journal of Food Science and Technology | Year: 2010

This study was conducted to compare the physicochemical properties of powdered green teas produced in Korea and Japan including particle size, color, chlorophyll, caffeine and theanine. The average particle size of Korean powered green tea (14.63-25.39 μm) was similar to that of Japanese powdered green tea (15.46-21.02 μm). The surface color of shade-cultivated Haenam Green Tea (HN-1) had the highest negative 'a' value, which represents 'green' color. When the TCD (total color difference value) was measured in the samples, HN-1 was most similar to the premium powdered green tea of Japan (JA-1). Domestic shade-cultivated powdered green teas had 1.5-2 times greater chlorophyll content than powdered green teas produced from plants that were not cultivated in the shade. The presence of chlorophyll a resulted in a higher intensity of green color than the presence of chlorophyll b. A significant negative correlation was also observed between the color and the chlorophyll a, chlorophyll b and total chlorophyll contents. Specifically, chlorophyll a had the greatest impact on the green color of powdered green tea. The content of catechins, caffeine and theanine in Korean powdered green teas ranged from 14.679-20.128, 1.496-3.237 and 0.926-1.977 g/100 g, respectively. The caffeine and theanine contents were high in shade-cultivated powdered green teas. Based on the above results, domestic powdered green teas cultivated under shaded conditions had a quality similar to that of medium-quality green teas produced in Japan, and the overall quality of Korean powdered green tea was poorer than that of Japanese powdered green tea. © The Korean Society of Food Science and Technology.

Chung S.K.,Korea University | Seo J.Y.,Korea University | Seo J.Y.,Lotte R and nter | Lim J.H.,Lotte R and nter | And 8 more authors.
Journal of Stored Products Research | Year: 2011

The barrier property of different types of plastic film (with or without pinholes) against two insects, Plodia interpunctella (Hübner) larvae and Tribolium castaneum (Herbst) adults, and the morphology of damage produced in these insects were investigated. Using a penetration apparatus, four types of plastic films varying in thickness were used for insect-penetration tests: casted polypropylene, 20 μm and 25 μm (CPP20 and CPP25); oriented polypropylene, 20 μm and 30 μm (OPP20 and OPP30); linear low-density polyethylene, 40 μm and 50 μm (LLDPE40 and LLDPE50); and polyethylene terephthalate 12 μm and 16 μm (PET12 and PET16). After being fixed and tested in the penetration apparatus, each film was cut into a disc shape and 10 holes (200 μm diameter) were made by a pin. The shape of film damage and the mouthparts of insects were observed using scanning electronic microscopy. Plodia interpunctella larvae could penetrate all films with pinholes, while T. castaneum adults were unable to penetrate any of the films tested, even those with pinholes. The penetration-percentages by P. interpunctella larvae were 38% (LLDPE40), 3% (LLDPE), 53% (CPP20), 37% (CPP25), 63% (OPP20), 43% (OPP30), 83% (PET12) and 63% (PET16). The elongation value, tensile strength and thickness of film were important factors in the penetration test. LLDPE, which has the highest elongation value and the lowest tensile strength value, was the film that best protected against insect penetration. In CPP and LLDPE films, there were many scratches and tears around the holes. In comparison, much less damage was observed around the holes in OPP and PET films. By observing the mouthparts of insects, it was determined that P. interpunctella larvae had sharper mandibles than those of T. castaneum adults. © 2011 Elsevier Ltd.

Bang D.Y.,Yonsei University | Bang D.Y.,Lotte R and nter | Byeon S.K.,Yonsei University | Moon M.H.,Yonsei University
Journal of Chromatography A | Year: 2014

A simple and fast lipid extraction method from human blood plasma and urine is introduced in this study. The effective lipid extraction from biological systems with a minimization of the matrix effect is important for the successful qualitative and quantitative analysis of lipids in liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS). The method described here is based on the modification of the quick, easy, cheap, effective, rugged and safe (QuEChERS) extraction method, which was originally developed for pesticide residue analysis in food, for the purpose of isolating lipids from biological fluids. Applicability of QuEChERS method for lipids was evaluated by varying organic solvents for the extraction/partitioning of lipids in MgSO4/CH3COONa for the removal of water and by varying sorbents (primary secondary amines, graphitized carbon black, silica, strong anion exchange resins and C18 particles) for the dispersive solid-phase extraction (dSPE) step. This study shows that 2:1 (v/v) CHCl3/CH3OH is effective in the extraction/partitioning step and that 50mg of C18 particles (for 0.1mL plasma and 1mL of urine) are more suitable for sample cleanup for the dSPE step of the QuEChERS method. Matrix effects were calculated by comparing the recovery values of lipid standards spiked to both plasma and urine samples after extraction with those of the same standards in a neat solution using nanoflow LC-ESI-MS/MS, resulting in improved MS signals due to the decrease of the ion suppression compared to the conventional Folch method. The modified QuEChERS method was applied to lipid extracts from both human urine and plasma samples, demonstrating that it can be powerfully utilized for high-speed (<15min) preparation of lipids compared to the Folch method, with equivalent or slightly improved results in lipid identification using nLC-ESI-MS/MS. © 2014 Elsevier B.V.

Bang D.Y.,Yonsei University | Bang D.Y.,Lotte R and nter | Lim S.,Yonsei University | Moon M.H.,Yonsei University
Journal of Chromatography A | Year: 2012

The effect of ionization modifiers added to the mobile phase of nanoflow liquid chromatography-tandem mass spectrometry (nLC-ESI-MS 3) on the simultaneous analysis of all phospholipid (PL) classes in negative ion mode has been investigated. While MS analysis of most PL classes is carried out in negative ion mode, analysis of neutral polar (polar but electrically neutral) lipids like phosphatidylcholine (PC) and sphingomyelin (SM) is highly efficient in positive ion mode. Therefore, analysis of PL mixture samples often requires two separate runs in both positive and negative ion mode. In order to establish run conditions to carry out a single nLC-ESI-MS-MS for all PLs, the ionization efficiency of 13 different types of PL molecules in nLC-ESI-MS has been evaluated in negative ion mode by varying the modifiers and their concentrations. Experiments demonstrated that a mixture of 0.05% ammonium hydroxide and 1mM ammonium formate added to the mobile phase provided effective ionization for all classes of PLs. The optimized conditions were applied to the analysis of a phospholipid mixture extracted from a human urine sample, yielding the identification of a total of 85 PL species. Analysis of the same sample with dual nLC-ESI-MS 2 runs in both positive and negative ion mode confirmed that nLC-ESI-MS 3 with the mixed modifier run only in negative ion mode gave comparable results. © 2012 Elsevier B.V.

Chung S.K.,Korea University | Seo J.Y.,Korea University | Seo J.Y.,Lotte R and nter | Lim J.H.,Lotte R and nter | And 4 more authors.
Journal of Food Science | Year: 2013

Microcapsules containing thyme oil were prepared by in situ polymerization, using melamine-formaldehyde prepolymer as a wall material and 3 different emulsifiers (pluronic F-127, tween 80, and sodium lauryl sulfate [SLS]). The general characteristics and release behavior of microcapsules, and their repellent effect against insects were investigated. The morphology of microcapsules using SLS was spherical shape with smooth surface. Microcapsules began to degrade at 150 °C. The particle size ranged from 1 to 10 μm and the loading efficiency of thyme oil was clearly affected by the emulsifier type. The highest loading efficiency appeared in microcapsules using SLS, which have good thermal resistance and smooth surface. The release rate of thyme oil from microcapsules was not only dependent on the storage temperature but also emulsifier type and microcapsules showed the sustained release properties for a long time. Diets, which were mixed with encapsulated thyme oil, expressed high insect repellent efficacy over 90% for 4 wk. Practical Application: Essential oil has various pest-control characteristics, including repellent, ovicidal, and antifeedant efficacy. This work showed the sustained release properties and long-lasting repellency of encapsulated essential oil. The results suggest that the great potential of essential oil microcapsules can be applied in coating or printing of food packaging materials for the insects repelling effects. © 2013 Institute of Food Technologists®.

Lim S.,Yonsei University | Bang D.Y.,Yonsei University | Bang D.Y.,Lotte R and nter | Rha K.H.,Yonsei University | Moon M.H.,Yonsei University
Bulletin of the Korean Chemical Society | Year: 2014

Ultrahigh performance liquid chromatography-electrospray ionization-tandem mass spectrometry (UPLCESI-MS/MS) provides a high-speed method to screen a large number of samples for small molecules with specific properties. In this study, UPLC-ESI-MS/MS with multiple reaction monitoring (MRM) was employed to screen urinary phospholipid (PL) content for biomarkers of prostate cancer. From lists of urinary PLs structurally identified using nanoflow LC-ESI-MS/MS, 52 PL species were selected for quantitative analysis in urine samples between 22 cancer-free urologic patients as controls and 45 prostate cancer patients. Statistical treatment of data by receiver operating characteristic (ROC) analysis yielded 14 PL species that differed significantly in relative concentrations (area under curve (AUC) > 0.8) between the two groups. Among PLs present at higher levels in prostate cancer urine, phosphatidylcholines (PCs) and phosphatidylinositols (PIs) constituted the major head group PLs (3 PCs and 7 PIs). For technical reasons, PL species of low abundance may be underrepresented in data from UPLC-ESI-MS/MS performed in MRM mode. However, the proposed method enables the rapid screening of large numbers of plasma or urine samples in the search for biomarkers of human disease.

Bang D.Y.,Yonsei University | Bang D.Y.,Lotte R and nter | Moon M.H.,Yonsei University
Journal of Chromatography A | Year: 2013

An on-line two-dimensional liquid chromatography method was developed for comprehensive lipid profiling by coupling strong anion exchange (SAX) and nanoflow reversed-phase liquid chromatography (nRPLC) prior to electrospray ionization-tandem mass spectrometry (2D-SAX/nRPLC-ESI-MS/MS). Lipids can be classified into four different types according to the electrical propensities of the lipids: anionic, weak anionic, neutral polar, and special lipids. In 2D-SAX/nRPLC, various lipids can be fractionated in the first dimension (SAX: 5. μm to 100. Å, 5.0. cm. ×. 75. μm i.d.) by step elution (methanol and salt solution), followed by the molecular separation of lipids in the second dimension (RP: 3. μm to 100. Å, 7.0. cm. ×. 75. μm i.d.) with binary gradient LC. Since the elution of lipids from SAX can be achieved with a very small volume of eluent delivered from an autosampler, it can be simply implemented with an LC-ESI-MS instrument for full automation, and the salt step elution, including the two-step injection procedure, can be used for the selective analysis of the desired lipid fraction. For nRPLC-ESI-MS/MS run in either positive or negative ion mode, a common ionization modifier (0.05% ammonium hydroxide with 5. mM ammonium formate) was introduced into the binary mobile phase solutions so that 2D-LC-MS could be operated in both ion modes without changing the mobile phase solutions. The developed on-line 2D-SAX/nRPLC-ESI-MS/MS was evaluated with 22 different standard lipids for the optimization of the salt step elution and was applied to a healthy human plasma lipid extract, resulting in the identification of a total of 303 plasma lipids, including 14 different classes. © 2013 Elsevier B.V.

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