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Ellagic acid glucoside was synthesized via transglucosylation using sucrose and glucansucrase derived from Leuconostoc mesenteroides B-512 FMCM. After such enzymatic synthesis, the product was purified by 50% ethyl acetate fraction and C18 column chromatography. Modification of ellagic acid glucoside was verified by LC–MS/MS at m/z 485.1 (M + Na)− and m/z 531.1 (M + 3Na)−. The yield of ellagic acid glucoside was 69% (3.47 mM) by response surface methodology using 150 mM sucrose, 300 mU/mL glucansucrase, and 5 mM ellagic acid. The synthesized ellagic acid glucoside showed improved water solubility, up to 58% higher brain nerve cell (SH-SY5Y) protective effect, threefold higher cortisol reducing effect, and fourfold stronger inhibitory effect on acetylcholinesterase (AChE) than ellagic acid. These results indicate that ellagic acid glucoside could be used as a neuroprotective agent.

Gallic acid (GA) is a functional ingredient abundant in Chinese pu-erh tea. The aim of this study was to increase the GA content in green tea extracts using acid hydrolysis. (-)-Epigallocatechin gallate treated with 1 M hydrochloric acid at 110°C for 1 h resulted in a GA yield of 45.6%. However, under these conditions, (-)-epigallocatechin was easily oxidized and rendered undetectable. On applying the same treatment to green tea extracts of Korea-cultivated Chamnok, a native species, and Yabukita, the GA contents increased from 0.17 to 4.87, 0.28 to 5.33 and 0.17 to 4.44 mM, respectively. In Chamnok extracts prepared following harvesting at three different time points, the GA contents increased from 0.17 to 4.48, 0.12 to 5.16 and 0.06 to 5.71 mM. Therefore, it is possible to produce green tea extracts with high GA concentrations using simple acid hydrolysis. This will greatly benefit the production of functional ingredients and will be useful in the beverage industry. Key words: Domestic cultivar, EGCG, EGC, tannase.

We report the cause of degradation of low-temperature amorphous indium-gallium-zinc-oxide (a-IGZO) coplanar thin-film transistors (TFTs). As the deposition temperature of the buffer layer was changed from 400 to 200 °C, the field-effect mobility decreased considerably from 15 to 3 cm2 V−1 s−1, the subthreshold swing (SS) increased from ~ 150 to 280 mV dec−1, the threshold voltage shift (ΔVth) under negative bias temperature stress (NBTS) increased from − 0.27 to − 0.33 V, and ΔVth under a positive bias temperature stress (PBTS) increased significantly from 0 to 4.9 V. From the results of high-resolution transmission electron microscopy (HR-TEM) and X-ray reflectivity (XRR), the poor roughness created by sputtering damage of the interface between the gate insulator (GI) and the a-IGZO is the cause of degradation. In addition, through an atomic probe tomography (APT) analysis, the reason low-temperature TFTs have poorer PBTS stability than NBTS is carefully to be due to zinc (Zn)-related defects that create ionized oxygen vacancies. Based on these results, we introduce strategies for realizing low-temperature oxide TFTs using vacuum process. Please confirm if the author names are presented accurately and in the correct sequence as given name, middle name/initial, family name. Also, kindly confirm the details in the metadata are correct. We confirmed all author names. Please check and confirm that the authors and their respective affiliations have been correctly identified and amend if necessary. We checked all authors and their affiliations.

Due to the nutritional value of rice cakes, there is renewed interest in this traditional Korean food, and thus various efforts have been made to improve its storage stability. In this study, lactic acid bacteria that produce exopolysaccharides (EPS) were isolated and their physiochemical properties were analyzed. The bacteria were used to produce ‘Sulgidduk’ (a Korean rice cake) with improved storage stability. Among the 107 strains isolated from traditional fermented foods, only five strains were confirmed to produce EPS in MRS media with 10% sucrose. Two of these strains were identified as members of the genus Weissella and three were identified as the Bacillus genus via sequence analysis of 16S rDNA. Among the five strains, the strain Weissella cibaria JNU29 was selected for application to ‘Sulgidduk’, since it is food applicable, viable in artificial gastric and bile juices, and produces the highest content of EPS (16.72 g/L). TLC and HPLC analysis showed that the EPS produced by W. cibaria JNU29 strain was a homopolysaccharide composed of only glucose. A culture solution of the W. cibaria JNU29 strain was mixed with milled rice flour to prepare ‘Sulgidduk’. After incubation for 48 h, the ‘Sulgidduk’ showed lower hardness values than that of the control without the culture solution, and the lactic acid bacteria survived to a level of 7 log CFU/g. Thus, the W. cibaria JNU29 strain, which produces EPS, can be applied for the production of ‘Sulgidduk’, as it delays retrogradation and prevents mold-induced decay to improve shelf life.

We examined the efficacy of fermented

This study focused on the physiochemical characteristics of the oligosaccharide produced in preserved yuzu by NY 518 and its functions based on the intestinal health through antimicrobial activities. NY 518 was identified as Lactobacillus sakei. The oligosaccharide produced by L. sakei NY 518 was gluco-oligosaccharide. The oligosaccharide from preserved yuzu (OY) was found to have lower degree of polymerization than the oligosaccharide from sucrose (OS) owing to the presence of tri- to nona-saccharides. These oligosaccharides had lower pH and increased acidity, soluble solids, and viscosity than their substrates. OY had 67% α-glucosidase inhibition activity of OS and higher antibacterial effects on food-poisoning bacteria than OS. These results indicate that the oligosaccharide produced by L. sakei NY 518 in sugar-preserved foods exhibits beneficial functions (antidiabetic and antibacterial activities) and could be a good substitute for sugar.

Three major yuzu varieties, Native, Namhae, and Tadanishiki in Korea were investigated on physiochemical properties and functional characterizations with respect to neuroprotective function (SH-SY5Y cells) or anti-inflammatory (Raw 264.7 cells). Among the three cultivars tested, Namhae had significantly higher fruit weight and total dietary fibers, while Tadanishiki had higher values of both total flavonoid and antioxidant activity. As functional compounds, Tadanishiki contained a 133% of hesperidin and 164% of naringin, compared to those of Native or Namhae. In comparison to other yuzu, Tadanishiki showed the higher cell viability, lower AChE content, lower protein levels of Bcl-2 /Bax, Caspase 3, and PARP at scopolamine-treated SH-SY5Y nerve cell. Tadanishiki and Namhae were effective for anti-inflammation by decreasing of NO production in LPS-induced Raw 264.7 cells. These results indicate that Tadanishiki yuzu, could be useful for application as a possible natural functional additive with high hesperidin content and excellent neuroprotective and anti-inflammation effects.

This research focused on physiochemical and nutritional properties and functional characterization of three cultivars of yuzu—Native, Tadanishiki yuzu, and Namhae1—during different seasons. According to the cultivar and harvest time, yuzu cultivars were analyzed for free sugar, dietary fiber, hesperidin, naringin, and flavonoid content as well as antioxidant and antihypertensive activity. During November, Namhae1 exhibited the highest fruit weight, °Brix/acidity ratio, and total dietary fiber content. Tadanishiki contained the highest fructose and sucrose levels, pectin and cellulose contents, and soluble dietary fiber. Tadanishiki also had the highest hesperidin content in October, while the naringin content and antioxidant activity were the greatest in November. Antihypertensive activity was also the strongest for Tadanishiki, which was picked in October and November. These results indicated that Tadanishiki in October or November was the best for consumption or favorable processing because of its excellent product quality and high levels of nutritional and functional compounds.

An ion accelerator, RAON, is going to be built in Daejeon, Korea, by the Rare Isotope Science Project (RISP) team in the Institute of Basic Science (IBS). In this accelerator, various ions, such as uranium, proton, carbon and calcium, will be accelerated and fed to researchers for experiments. To produce the ion beams and to satisfy the requirements, many devices such as accelerating structures, RF power supplies and ion sources will be installed and controlled according to the predefined control logic. For correct control of such devices, time and clock synchronization is essential. A time synchronization test bed is planned for the RAON superconducting radio-frequency (SRF) test facility, and a flexible, low-cost gps-based time server was developed for that purpose. In this paper, detailed information on the developed GPS server and the test results will be described.

Kiwifruit (Actinidia chinensis, Hayward) was stored at 25℃ for 0~30 days and investigated to find out the optimum storage time to obtain the best physical and functional properties for consumers’ preference. Kiwifruits was stored at different time period (0, 5, 10, 15, 20, and 30 days) for investigating their physiochemical quality, nutritional components, and functional characteristics. Kiwifruits stored for 20~30 days showed the best physiochemical quality such as higher total acidity and proper firmness. They were also more enriched with dietary fibers, free sugar, and organic acid, although no significant changes were observed in crude protein, crude fat, and moisture content. For functional properties, kiwifruits stored for 20 days showed significantly higher contents of total phenolics, flavonoids, and actinidin. In addition, it showed stronger antioxidant activity, whitening effect, and proteolytic activity when compared with other samples. SDS-PAGE analysis showed the presence of actinidin enzyme in kiwifruits. These results indicated that the kiwifruits stored for 15~20 days possessed excellent quality and high concentrations of nutritional and functional compounds, which could be best for both fresh consumption and product processing

Glucosyl rubusosides were synthesized by two dextransucrases. LcDexT was obtained from Leuconosotoc citreum, that LlDexT was obtained from Leuconostoc lactis. LcDexT and LlDexT regioselectively transferred a glucosyl residue to the 13-O-glucosyl moiety of rubusoside with high yield of 59-66% as analyzed by TLC and HPLC. Evaluation of the sweetness of these glucosyl rubusosides showed that their quality of taste, in particular, was superior to that of rubusoside. These results indicate that transglucosylation at the 13-O-glucosyl moiety of rubusoside by different regioselective dextransucrases can be applicable for increasing its sweetness and quality of taste.

The total phenolic and flavonoid content and antioxidative activities during production of pear juice concentrate (PJC) from two cultivars, Hwasan and Niitaka, were investigated. The main processing steps in PJC production are washing, pressing, pasteurization, clarification, filtration, evaporation, and packaging. Total phenolic and flavonoid content of end-product PJC from Niitaka decreased by 53.11 and 46.47%, respectively, while those from Hwasan decreased by 55.46 and 36.09%, respectively, compared to the phenolic and flavonoid content of original fresh fruit. DPPH radical-scavenging activities, reducing power and nitrate radical-scavenging activities showed a similar tendency as total phenolic and flavonoid content; that is, they decreased in juice concentrate made from both cultivars. Also, antioxidant activities of press cake waste (skin and seeds) from Niitaka and Hwasan pears were higher than fresh pears. In conclusion, antioxidant levels were significantly affected during processing of PJC, especially during the pressing step in which press cake waste retains the seeds and skin.

This study was performed to characterize pear protease proteolytic activity and investigate the use of pear protease as a meat tenderizer. Pear protease was purified and stabilized by 5% dextrin during lyophilization (dry) or concentration (liquid). Pear protease was further characterized with respect to pH, thermodynamics, and enzyme kinetics. Pear protease was stable at a pH range of 5-8 with an optimum pH of 6.5. From Arrhenius plots, liquid protease showed higher temperature dependency (23.49 kJ/mol) than dry protease (18.62 kJ/mol) due to its higher activation energy. The kcat/Km, catalytic efficiency of enzyme, was similar with 2.9 and 2.7 µM/min with dry and liquid proteases. Pear protease was evaluated for its proteolytic activities with casein and beef myofibrillar proteins by individually and combination with fig and kiwifruit proteases. These result indicated that pear and kiwifruit proteases could be complementary to be a desirable product for meat tenderization.

Different ascorbic acid (AA) concentrations of 0.16, 0.20, and 0.24% (w/v) were added to pear juice from the new cultivar Pyrus pyrifolia Nakai cv. "Sinhwa". Enzymatic browning reduction and antioxidant activity were analyzed after 24 h at 37°C. Juices with 0.20% added AA showed the highest inhibition of 78.8% of polyphenol oxidase (PPO) activity. L* values of juices a with 0.20 and 0.24% added AA decreased more slowly than controls lacking AA addition and juice with 0.16% added AA after storage for 24 h. Browning indices of juices with added AA were lower than for controls. However, indices increased after storage for 24 h. The DPPH radical-scavenging activity, reducing power, and nitrite scavenging activity of all juices with added AA were higher than for controls and decreased after storage for 24 h. Addition of 0.20% AA to pear juice from the new "Sinhwa" cultivar showed the highest browning activity reduction.

We report the performance improvement of low-temperature coplanar indium&ndash, gallium&ndash, zinc&ndash, oxide (IGZO) thin-film transistors (TFTs) with a maximum process temperature of 230 &deg, C. We treated F plasma on the surface of an SiO2 buffer layer before depositing the IGZO semiconductor by reactive sputtering. The field-effect mobility increases from 3.8 to 9.0 cm2 V&minus, 1&middot, s&minus, 1, and the threshold voltage shift (&Delta, Vth) under positive-bias temperature stress decreases from 3.2 to 0.2 V by F-plasma exposure. High-resolution transmission electron microscopy and atom probe tomography analysis reveal that indium fluoride (In-F) nanoparticles are formed at the IGZO/buffer layer interface. This increases the density of the IGZO and improves the TFT performance as well as its bias stability. The results can be applied to the manufacturing of low-temperature coplanar oxide TFTs for oxide electronics, including information displays.

This study was performed to compare the total protein and protease content among the whole fruit, flesh, and peel of nine different pear cultivars. Pear proteases were functionally characterized with respect to three enzyme assays. Proteases from pears were further identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, in gel activity staining, and matrix assisted laser desorption/ionization-time of flight mass spectrometry analysis. Flesh from Whasan, Nikita, and Hanareum cultivars contained relatively more total protein and protease and showed high enzyme activities, while Chuwhang contained the lowest amount of protein and protease activity. Protease content and enzyme activities found in the pear flesh or whole fruits were two to six times higher than those in the pear peel. Pear cultivars contained one or two protease bands with molecular weights of 36 kDa and/or 38k Da. The larger band was further identified as a cysteine proteinase with 70% homology to the pear cysteine protease f...

Chlorogenic acid, a major polyphenol in edible plants, possesses strong antioxidant activity, anti-lipid peroxidation and anticancer effects. It used for industrial applications; however, this is limited by its instability to heat or light. In this study, we, for the first time synthesized chlorogenic acid glucoside (CHG) via transglycosylation using dextransucrase from Leuconostoc mesenteroides and sucrose. CHG was purified and its structure determined by nuclear magnetic resonance and matrix-associated laser desorption ionization–time-of-flight mass spectroscopy. The production yield of CHG was 44.0% or 141 mM, as determined by response surface methodology. CHG possessed a 65% increase in water solubility and a 2-fold browning resistance and it displayed stronger inhibition of lipid peroxidation and of colon cancer cell growth by MTT assay, compared to chlorogenic acid. Therefore, this study may expand the industrial applications of chlorogenic acid as water-soluble or browning resistant compound (CHG) through enzymatic glycosylation.

The effects of treatment with various complex carbohydrases such as Pectinex, Celluclast, Viscozyme, and Ultraflo on the physiochemical properties, polyphenol extraction yields and antioxidant activities of pear peel and pear core were investigated. When pear peel and pear core were treated with complex carbohydrases, the soluble solid content of peel increased, whereas it did not change significantly in the case of pear core. When pear peel and pear core were treated with Pectinex, significant improvement of soluble solid content was observed along with the highest extraction yield of reducing sugar content. Total sugar content increased in most of the enzyme treatment groups. In the case of pear peel, the Viscozyme treatment group showed the highest total polyphenol contents, total flavonoid contents, DPPH radical scavenging activity, ABTS radical scavenging activity, and SOD-like activity. When the flesh and core of pear were treated with Celluclast, total polyphenol contents increased. All enzyme treatment groups except for the Ultraflo treatment group showed increases in total flavonoid contents. With regard to pear flesh, the Celluclast group showed the highest DPPH radical scavenging activity. When pear core was treated with the four complex carbohydrases, DPPH radical scavenging activity and ABTS radical scavenging activity did not increase significantly. However, the SOD-like activity of all enzyme treatment groups significantly increased. Consequently, dry matter and soluble solid contents, polyphenol content, and antioxidant activity of pear peel and core could be improved by complex carbohydrase treatment.

전남농업기술원 식품연구소This study was carried out to optimize the filtration, clarification, anti-browning processing conditions of clear pear juice and to investigate changes in antioxidant activity of pear juice produced through different heating treatment. For the filtration with cheese cloth, filter paper, or centrifugation (10 min at 3,000 rpm), the pear juice was most efficiently filtered with centrifugation because it showed the highest lightness (L value) and lowest yellowness (a value). Among various clarifying agents, 1% of gelatin or bentonite clarified effectively pear juice but tannin or egg albumin did not. Among anti-browning agents (0.1%) like L-ascorbic acid, NaCl or citric acid, L-ascorbic acid prevented the browning of pear juice with the lowest browning index value (2.62), compared to that of NaCl (2.74), or citric acid (2.87). Fructose, sucrose, glucose and sorbitol were present in the pear juice, the fructose and glucose contents increased but that of sucrose decreased in the heated pear juice. The total polyphenol content of the heated pear juice significantly increase, and did the total flavonoid contents in the clear and heated pear juice. The DPPH radical scavenging activity and nitrate scavenging activity were higher in the clear and heated pear juice than in the fruit crush. Key words antioxidant activity, clarification, Chuhwangbae, pear juice

This study was performed to confirm physiological activities according to parts of new pear cultivars (Gamcheonbae, Manpungbae, Chuwhangbae, Hanareum) and Niitaka pear. The total polyphenol compound contents of pear peel, flesh and core were 178~235, 95~113, 177~229 mg/100 g as tannic acid equivalent, respectively. There were differences in the contents by cultivars, Chuwhangbae and Hanareum cultivars showed high contents. The total flavonoid contents of the pear peel, flesh and core were 29.2~40.2, 24.3~34.3, 26.9~38.8 mg/100 g, respectively and those of Chuwhangbae and Gamcheonbae cultivars showed comparatively high values. The electron-donating ability was high in Chuwhangbae, Gamcheonbae and in the pear peel (29.7~57.7%), core (29.1~38.2%), flesh (7.6~17.7%), in that order. The nitrate scavenging activity was highest in that pear peel (21.0~49.8%), followed by the core (11.8~16.2%) and flesh (7.8~9.7%), but there was little difference by cultivar.

Additional file 1: Figure S1. MALDI ionization spectrum of gallic acid glucoside. Table S1. Independent variables, levels, and experimental codes used in response surface methodology (RSM). Table S2. ANOVA for RSM parameters fitted to second-order polynomial equations.

The human fibroblast collagenase catalytic domain (MMP1ca) that is considered a prototype for all interstitial collagenase and plays an important role in the turnover of collagen fibrils in the matrix was expressed as an inclusion body in the Escherichia coli. The purified enzyme displayed activity with substrate Dnp-Pro-Leu-Ala-Leu-Trp-Ala-Arg-OH with a K(m) value of 26.61±1.42 μM. The inhibition activity of the nine flavonoid compounds and gallic acid against MMP1ca was examined. Among the compounds tested, the IC(50) of seven flavonoid compounds were determined and ranged from 14.13 to 339.21 μM. Epigallocatechin gallate (EGCG) showed the highest inhibition toward MMP1ca with IC(50) values of 14.13±0.49 μM. EGCG showed a competitive inhibition pattern with a K(i) value of 10.47±0.51 μM. The free binding energy of EGCG against MMP1ca was -13.07 kcal mol(-1), which was calculated by using Autodock 3.0.5 software and showed numerous hydrophobic and hydrogen bond interactions. The galloyl group of EGCG, gallocatechin gallate and epicatechin gallate was determined to be important for inhibitory activity against MMP1ca.

A novel endodextranase isolated from Paenibacillus sp. was found to produce isomaltotetraose and small amounts of cycloisomaltooligosaccharides with a degree of polymerization of 7-14 from dextran. To determine the active site, the enzyme was modified with 1-ethyl-3-[3- (dimethylamino)-propyl]-carbodiimide (EDC) and α-epoxyalkyl α-glucosides (EAGs), an affinity labeling reagent. The inactivation followed pseudo first-order kinetics. Kinetic analysis and chemical modification using EDC and EAGs indicated that carboxyl groups are essential for the enzymatic activity. Three Asp and one Glu residues were identified as candidate catalytic amino acids, since these residues are completely conserved across the GH family of 66 enzymes. Replacement of Asp189, Asp340, or Glu412 completely abolished the enzyme activity, indicating that these residues are essential for catalytic activity.

Acarbose-fructoside (acarbose-Fru) was newly synthesized via the acceptor reaction of a levansucrase from Leuconostoc mesenteroides B-512 FMC with acarbose and sucrose. The resultant product was separated with 10.5% purification yield via Bio-gel P-2 column chromatography and HPLC. Its structure was determined to be 1 I -β- d -fructofuranosyl α-acarbose, according to the results of 1 H, 13 C, HSQC, and HMBC analyses. Acarbose-Fru was inhibited competitively on α-glucosidase ( A. niger and baker's yeast) but mixed noncompetitively on α-amylases ( A. oryzae and porcine pancreatic). Compared to acarbose, acarbose-Fru exhibited inhibition potency of 1.12 or 1.52 on A. niger α-glucosidase or A. oryzae α-amylase, respectively. Additionally, acarbose-Fru was identified as a novel substrate for dextransucrase with K m and V max values of 189.0 mM and 8.51 μmol/(mg min), respectively. Therefore, acarbose-Fru as a substrate might be synthesized novel acarbose derivatives by using dextransucrase.

Hydroquinone (HQ) functions as a skin-whitening agent, but it has the potential to cause dermatitis. We synthesized a HQ fructoside (HQ-Fru) as a potential skin-whitening agent by reacting levansucrase from Leuconostoc mesenteroides with HQ as an acceptor and sucrose as a fructofuranose donor. The product was purified using 1-butanol partition and silica-gel column chromatography. The structure of the purified HQ-Fru was determined by (1)H and (13)C nuclear magnetic resonance, and the molecular ion of the product was observed at m/z 295 (C12 H16 O7 Na)(+). The HQ-Fru was identified as 4-hydroxyphenyl-beta-D: -fructofuranoside. The optimum condition for HQ-Fru synthesis was determined using a response surface method (RSM), and the final optimum condition was 350 mM HQ, 115 mM sucrose, and 0.70 U/ml levansucrase, and the final HQ-Fru produced was 1.09 g/l. HQ-Fru showed anti-oxidation activities and inhibition against tyrosinase. The median inhibition concentration (IC(50)) of 1,1-diphenyl-2-picrylhydrazyl scavenging activity was 5.83 mM, showing higher antioxidant activity compared to beta-arbutin (IC(50) = 6.04 mM). The K ( i ) value of HQ-Fru (1.53 mM) against tyrosinase was smaller than that of beta-arbutin (K ( i ) = 2.8 mM), indicating that it was 1.8-times better as an inhibitor. The inhibition of lipid peroxidation by HQ-Fru was 105.3% that of HQ (100%) and 118.9 times higher than that of beta-arbutin (0.89% of HQ).

Expression of NtNEK2(DD), a constitutively active mutant of NtMEK2, activates endogenous salicylic acid-induced protein kinase (SIPK) and wounding-induced protein kinase (WIPK), and leads to several stress/defense responses in tobacco. In this study, we used ACP (annealing control primer)-based differential display reverse transcription-PCR to isolate the downstream effectors mediated by the NtMEK2-SIPK/WIPK cascade. The arginine decarboxylase gene (ADC), which is involved in plant putrescine biosynthesis, was one of nine differentially expressed genes. When compared with NtMEK2(KR) plants, NtMEK2(DD) transgenic plants exhibited a significant increase in ADC and ODC (ornithine decarboxylase) transcript levels, as well as in putrescine and its catabolite, gamma-aminobutyric acid, following SIPK/WIPK activation. Taken together, these results suggest that the NtMEK2-SIPK/WIPK cascade is involved in regulating polyamine synthesis, especially putrescine synthesis, through transcriptional regulation of the biosynthetic genes in tobacco.

Two arbutin glucosides were synthesized via the acceptor reaction of a glucansucrase from Leuconostoc mesenteroides B-1299CB with arbutin and sucrose. The glucosides were purified by Bio-gel P-2 column chromatography and high-performance liquid chromatography, and the structures were elucidated as 4-hydroxyphenyl beta-isomaltoside (arbutin-G1), 4-hydroxyphenyl beta-isomaltotrioside (arbutin-G2), according to the results of (1)H, (13)C, heteronuclear single-quantum coherence, (1)H-(1)H COSY, and heteronuclear multiple-bond correlation analyses. Arbutin glucoside (4-hydroxyphenyl beta-isomaltoside) exhibited slower effects on 1,1-diphenyl-2-picrylhydrazyl radical scavenging and similar effects on tyrosinase inhibition, and increased inhibitory effect on matrix metalloproteinase-1 production induced by UVB than arbutin.

A method is presented for synthesizing thermo-, acid-stable oligosaccharides (TASO) from sucrose (2.5–4 M) using a dextransucrase prepared from Leuconostoc mesenteroides B-512FMCM. The degree of polymerization (DP) of oligosaccharides synthesized was from 2 to 11. TASO resisted hydrolysis of its glycosidic linkages at 140 °C and pH 6.0 for 1 h. It was stable at pH's ranging from 2 to 4 at 120 °C. These oligosaccharides effectively inhibited the formation of insoluble glucan, the growth and acid production of Streptococcus sobrinus. However, it stimulated the growth of probiotic organisms such as Bifidobaterium sp. TASO potentially can be used as sweeteners for the food and beverages where thermo- and acid-stable properties are required and as potential inhibitors of dental caries.

A method is presented for synthesizing thermo-, acid-stable glucooligosaccharides (TASOG) from sucrose (2.5-4 M) using a dextransucrase prepared from Leuconostoc mesenteroides B-512FMCM. The degree of polymerization (DP) of oligosaccharides synthesized was from 2 to 11. TASOG resisted hydrolysis of its glycosidic linkages at 140°C and pH 6.0 for 1 h. It was stable at pHs ranging from 2 to 4 at 120°C. A method for synthesizing fructo-oligosaccharides (TASOF) with high concentrations of sucrose (1-3 M) by using levansucrase prepared from L. mesenteroides B-1355C was also developed. The DP of oligosaccharides synthesized according to the present method ranged from 2 to over 15. The TASOF was also stable at pHs ranging from 2 to 4 under 120°C. The percentage of TASOF in the reaction digest was 95.7% (excluding monosaccharides; 4.3% was levan). Both oligosaccharides effectively inhibited the formation of insoluble glucan, and the growth and acid production of Streptococcus sobrinus. TASOG and TASOF potentially can be used as sweeteners for food and beverages where thermo- and acid-stable properties are required and as potential inhibitors of dental caries.

The total phenolic and flavonoid content and antioxidative activities during production of pear juice concentrate (PJC) from two cultivars, Hwasan and Niitaka, were investigated. The main processing steps in PJC production are washing, pressing, pasteurization, clarification, filtration, evaporation, and packaging. Total phenolic and flavonoid content of end-product PJC from Niitaka decreased by 53.11 and 46.47%, respectively, while those from Hwasan decreased by 55.46 and 36.09%, respectively, compared to the phenolic and flavonoid content of original fresh fruit. DPPH radical-scavenging activities, reducing power and nitrate radical-scavenging activities showed a similar tendency as total phenolic and flavonoid content; that is, they decreased in juice concentrate made from both cultivars. Also, antioxidant activities of press cake waste (skin and seeds) from Niitaka and Hwasan pears were higher than fresh pears. In conclusion, antioxidant levels were significantly affected during processing of PJC, especially during the pressing step in which press cake waste retains the seeds and skin.

Different ascorbic acid (AA) concentrations of 0.16, 0.20, and 0.24% (w/v) were added to pear juice from the new cultivar Pyrus pyrifolia Nakai cv. “Sinhwa”. Enzymatic browning reduction and antioxidant activity were analyzed after 24 h at 37°C. Juices with 0.20% added AA showed the highest inhibition of 78.8% of polyphenol oxidase (PPO) activity. L* values of juices a with 0.20 and 0.24% added AA decreased more slowly than controls lacking AA addition and juice with 0.16% added AA after storage for 24 h. Browning indices of juices with added AA were lower than for controls. However, indices increased after storage for 24 h. The DPPH radical-scavenging activity, reducing power, and nitrite scavenging activity of all juices with added AA were higher than for controls and decreased after storage for 24 h. Addition of 0.20% AA to pear juice from the new “Sinhwa” cultivar showed the highest browning activity reduction.

Leuconostoc mesenteroides NRRL B-1149 sucrose phosphorylase (SPase) gene, 1149sp, was isolated and characterized. It is composed of 1479 bp nucleotides and encodes a 1149SPase of 492 amino acid residues with a calculated molecular mass of 56.1 kDa. It has unique C-terminal amino acid sequence (439DVETPSDTTIKITRKDKSGENVAVLVANAADKTFTITANGEEILANTEADKQQL492). 1149sp was expressed in Escherichia coli and the purified 1149SPase specific activity was 1.49 U/mg for sucrose. The optimum temperature and pH for SPase activities were ranged broad between 20 and 50 °C, between pH 6.0 and 7.5, respectively. The optimum temperature and pH were 37 °C at pH 6.7 and it showed Km of 6.3 mM and kcat of 1.59 s−1 for sucrose. It had a broad range of acceptor specificity and transferred the glucosyl moiety of sucrose or glucose-1-phosphate to various acceptors.

A new technology for reducing photolithography process from a four step to a three step process in the fabrication of TFT LCD is introduced. The core technology for 3‐mask‐TFT processes is the lift‐off process [1], by which the PAS and PXL layers can be formed simultaneously. A different method of the lift‐off process was developed in order to enhance the performance of efficiency with conventional positive and not negative PR which is the generally used in other lift‐off process. In addition, the removal capacity of the ITO/PR in lift‐off process was evaluated. The evaluation results showed that the new process can be run in conventional TFT production condition. In order to apply this new process in existing TFT process, several tests were conducted to ensure stability of the TFT process. It was found that the outgases from PR on the substrate in ITO sputtering chamber do not raise any problem, and the deposited ITO film beside the PR has conventional ITO qualities. Furthemore, the particles th...

Novel ampelopsin glucosides (AMPLS-Gs) were enzymatically synthesized and purified using a Sephadex LH-20 column. Each structure of the purified AMPLS-Gs was determined by nuclear magnetic resonance, and the ionic product of AMPLS-G1 was observed at m/z 505 (C₂₁H₂₂O₁₃·Na)⁺ using matrix-assisted laser desorption ionization time-of-flight mass spectrometry. AMPLS-G1 was identified as ampelopsin-4'-O-α-D-glucopyranoside. The optimum condition for AMPLS-G1, determined using response surface methodology, was 70 mM ampelopsin, 150 mM sucrose, and 1 U/mL dextransucrase, which resulted in an AMPLS-G1 yield of 34 g/L. The purified AMPLS-G1 displayed 89-fold increased water solubility and 14.5-fold browning resistance compared to those of AMPLS and competitive inhibition against tyrosinase with a K(i) value of 40.16 μM. This value was smaller than that of AMPLS (K(i)=62.56 μM) and much smaller than that of β-arbutin (K(i)=514.84 μM), a commercial active ingredient of whitening cosmetics. These results indicate the potential of AMPLS and AMPLS-G1 as superior ingredients for functional cosmetics.