Food Science and Biotechnology
한국식품과학회 (Korean Society of Food Science and Technology)
- 월간
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- 1226-7708(pISSN)
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- 2092-6456(eISSN)
과학기술표준분류
- 농림수산식품 > 식량작물과학
- 농림수산식품 > 식품과학
Aim & Scope
The Food Science and Biotechnology (Food Sci. Biotechnol.; FSB) was launched in 1992 as the Food Biotechnology and changed to the present name in 1998. It is an international peer-reviewed journal published monthly by the Korean Society of Food Science and Technology (KoSFoST). The FSB journal covers; Food chemistry/food component analysis Food microbiology and biotechnology Food processing and engineering Food hygiene and toxicology Biological activity and nutrition in foods Sensory and consumer science s Consumer perception and sensory evaluation on processed foods are accepted only when they are relevant to the laboratory research work. As a general rule, manuscripts dealing with analysis and efficacy of extracts from natural resources prior to the processing or without any related food processing may not be considered within the scope of the journal. The FSB journal does not deal with only local interest and a lack of significant scientific merit. The main scope of our journal is seeking for human health and wellness through constructive works and new findings in food science and biotechnology field.
http://www.fsnb.or.kr/submission/ KSCI KCI SCOPUS SCI SCIE제16권4호
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Proanthocyanidins (PACs), also named condensed tannins, are polymers of flavan-3-ols such as (+ )-(gallo)catechin and (-)-epi(gallo)catechin. A proper analysis of the PACs, with difficult challenges due to their complex structures, is crucial in studies of cancer chemoprevention. Cancer is a leading cause of mortality around the world. Many experimental studies have shown that dietary PACs are potential chemopreventive agents that block or suppress against multistage carcinogenesis in both in vitro and in vivo models. Cancer chemoprevention by dietary PACs has been shown effective through different mechanisms of action such as antioxidant, apoptosis-inducing, and enzyme inhibitory activities. Good sources of dietary PACs are nuts, fruits, beans, chocolate, fruit juice, red wine, and green tea. The chemopreventive potential of dietary PACs should be considered together with their bioavailability in humans. The safety issues regarding carcinogenesis and gastrointestinal disorder are also reviewed.
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In this study, we optimized the production of
${\gamma}-polyglutamic$ acid (PGA) in soybean milk cakes (SMC) fermented with Bacillus subtilis GT-D and B. subtilis KU-A, to be utilized as a functional food ingredient. PGA production was dependent upon the glutamate content, fermentation time, and type of Bacillus sp. The consistencies of the SMCs fermented by B. subtilis GT-D and B. subtilis KU-A were highest after 36 hr of fermentation, and then decreased gradually. The SMC fermented by B. subtilis KU-A had a higher consistency than the SMC fermented by B. subtilis GT-D. In the presence of 10% defatted soy flour (DFS), 5% glutamate in the SMC was efficiently converted into polyglutamic acid (PGA) for 24 hr, indicating a conversion yield above 96%, but its conversion then decreased with higher concentrations of glutamate. The soluble solid content (mucilage) of the SMC fermented with B. subtilis KU-A was 9.5%(w/w), and composed of 65.6% PGA (Mw 1,536 kDa) and some polysaccharides. However, the SMC fermented with B. subtilis GT-D had a mucilage content of 7.8%(w/w), and was composed of 66.4% PGA (Mw 1,409 kDa), 11.5% levan, and some polysaccharides. The viscoelastic values of the mucilage obtained using B. subtilis KU-A were much higher than those of mucilage obtained using B. subtilis GT-D. Also, the G'-value (elastic modulus) was higher than the G"-value (viscous modulus). -
Kim, Seong-Hee;Kim, Jin-Young;Han, Woong;Jung, Byeong-Yeal;Chuong, Pham-Due;Joo, Hae-Jin;Ba, Hoa-Van;Son, Won-Geun;Jee, Young-Heun;Yoon, Byoung-Su;Lee, Yong-Soon;Lim, Yoon-Kyu 515
Rapid immunochromatographic assay (ICA) kits were developed using flagella-specific monoclonal antibodies (MAbs) and rabbit polyclonal antibodies for screening Listeria spp. in food. The establishment of different formats, MAb 2B1 as capture antibody and MAb 7A3 or rabbit polyclonal antibodies as detector antibody, was compared. The 2 formats of the ICA kit were shown to have specific reactions with Listeria and no cross-reactivity with any of the non-Listeria including Escherichia coli O157:H7 and Salmonella enteritidis. The detection limits of the ICA kit using the combination of gold-labeled MAb 7A3 and MAb 2B1 showed$1{\times}10^5$ and$1{\times}10^6\;CFU/0.1\;mL$ at 22 and$30^{\circ}C$ , respectively. The other format of the ICA kit using the combination of gold-labeled rabbit polyclonal antibodies and MAb 2B1 showed$1{\times}10^6\;CFU/0.1\;mL$ at$22^{\circ}C$ but weak signal at 30 culture. The format utilizing MAb was more sensitive than the one using polyclonal antibodies for capture antibody. Samples contaminated with L. monocytogenes 4b culture (9-10, 5-6, and 1-2 CFU/mL) on pork and pasteurized milk were confirmed as positive results. Current data suggests that this ICA kit is a rapid, simple and effective tool to screen for Listeria spp. in food. -
The physicochemical properties of sun-dried and cyclic freeze-thaw dried Alaska pollack were analyzed to compare the 2 drying processes. The moisture content and water activity of sun-dried Alaska pollack were higher than cyclic freeze-thaw dried and 1 year-aged cyclic freeze-thaw dried Alaska pollack (hwangtae). The relatively low temperatures used in cyclic freeze-thaw drying retards lipid oxidation compared to sun drying based on the acid and peroxide values, and the levels of thiobarbituric acid-reactive substances (TBARS) in the dried fish. The water holding capacity of cyclic freeze-thaw dried Alaska pollack aged for 1 year (hwangtae) under ambient conditions at the drying location was higher than that of sun-dried Alaska pollack. The swelling of myofibrilar filaments during cyclic freeze-thaw drying may be responsible for the softening of the dried muscle protein. Aging the cyclic freeze-thaw dried Alaska pollack for 1 year contributed to an increased yellowish color of the hwangtae.
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The objective of this study was to establish the optimum alcohol fermenting conditions for the processing of kiwi wine and vinegar products. Six yeast strains were examined for their alcohol production from kiwi at
$30^{\circ}C$ for 72 hr with continuous shaking at 100 rpm. Under these conditions, Saccharomyces kluyveri DJ97 produced the highest alcohol content of 10.2%. As the fermentation time extended to 96 hr, the alcohol content reached a maximum of 12.75%. The optimum alcohol fermenting conditions for kiwi fruit were accomplished when kiwi was added to an equal amount of water, inoculated with S. kluyveri DJ97 and fermented at$30^{\circ}C$ for 96 hr with continuous shaking. The content of soluble solids decreased as the alcohol concentration increased, whereas little change was observed in the pH and titratable acidity during the low temperature aging process. Other alcoholic compounds, such as methanol, isopropanol, n-propanol, isobutanol, and isoamylalcohol, tended to increase as fermentation progressed. -
Jeong, Mi-Ran;Cha, Jeong-Dan;Lee, Kyung-Yeol;Kil, Bong-Seop;Han, Jong-Hyun;Lee, Young-Eun 531
The aerial part of Artemisia iwayomogi Kitamura has traditionally been used for inflammation, infectious disease, cancer, pyretic, diuretic, liver protective effect, and choleretic purposes in Korea. We investigated that the essential oil induces apoptosis in KB cell as evidenced by Hoechst-33258 dye staining, flow cytometry (cell cycles), and DNA fragmentation for nuclear condensation and Western blotting for activation of caspases-3, -8, -9, Bax, Bcl-2, cytochrome c, and poly (ADP-ribose) polymerase (PARP) cleavage. In the present study, we found that the essential oil could induce apoptosis in KB cells, as characterized by DNA fragmentation, activation of caspase-3, -8, and -9, and PARP cleavage. The efficacious induction of apoptosis was observed as a dose-dependent. The essential oil-induced apoptotic cell death was accompanied by up-regulation of Bax and down-regulation of Bcl-2. The essential oil also caused the loss of mitochondrial membrane potential and cytochrome c release from mitochondria to cytosol. These findings indicate that mitochondrial pathways might be involved in the essential oil-induced apoptosis and enhance our understanding of the anticancer function of the essential oil in herbal medicine. -
Sophora flavescens AITON (Leguminosae) is a typical traditional Korean medical herb considered to exhibit antibacterial, anti-inflammatory, and antipyretic effects, and is also used for the treatment of skin and mucosal ulcers, sores, diarrhea, gastrointestinal hemorrhage, arrhythmia, and eczema. In this study, the compound sophoraflavanone G was isolated from the dried roots of S. flavescens by bioassay-guided fractionation. We then investigated the effects of various concentrations of sophoraflavanone G on cell viability and the induction of apoptosis in KB cells after an incubation of 24 hr. The results were determined by the following methods: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-terazolium bromide (MTT) assay, Hoechst-33258 dye staining, flow cytometry (cell cycle), and Western blotting for caspase-3 and poly (ADP-ribose) polymerase (PARP). We found sophoraflavanone G induced the apoptosis of KB cells in a dose-dependent manner that was verified by DNA fragmentation, apoptotic bodies, the sub-G1 ratio, caspase-3 activity, and cleavage of PARP. These results suggest that sophoraflavanone G has potent anti-proliferative effects on human oral epidermoid carcinoma cells, with the induction of apoptosis.
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Low-energy processing technology, which enhances the utility of defatted soybean flour (DSF), was developed using extrusion processing. DSF was extruded at different conditions using a twin screw extruder and then, dried at
$40^{\circ}C$ for 20 hr. The nitrogen solubility index (NSI), viscosity, water solubility index (WSI), and water absorption index (WAI) of DSF increased after extrusion processing. The density of DSF extrudates decreased with the decrease in water content from 53 to 33% and the increase in extrusion temperature from 110 to$160^{\circ}C$ . The addition of NaOH from 1.2 to 1.8% and citric acid from 1 to 5% increased the total solubility (TS) of DSF due to the decrease of protein coiling and hydrophobic bonds formation during extrusion processing. When viscozyme was reacted first, TS, NSI, and soluble carbohydrate content of DSF hydrolysates increased about 12, 6, and 7%, respectively, compared to them reacted with protease first. The TS and NSI of DSF hydrolysates were increased about 15 and 10%, respectively, by extrusion processing at alkaline and acidic pH. Extrusion processing at alkaline and acidic pH contributed the increase of efficiency to hydrolyze DSF samples using enzyme. -
The study was carried out to examine on the refiner discharge from Alaska pollock as a collagen resource by characterizing biochemical and functional properties of collagen. The refiner discharge from Alaska pollock surimi manufacturing was a good resource for collagen extraction according to the results of total protein, heavy metal, volatile basic nitrogen, collagen content, amino acid composition, and thermal denaturation temperature (TDT). TDT of acid soluble collagen from refiner discharge showed
$20.7^{\circ}C$ , which was similar to that of collagen from Alaska pollock muscle and was higher than that of collagen from Alaska pollock skin. TDT of acid-soluble collagen from refiner discharge was, however, lower than those of skin collagens from warm fish and land animal. Acid-soluble collagen from refiner discharge of Alaska pollock could be used as a functional ingredient for food and industrial applications according to the results of water and oil absorption capacities, and emulsion properties. In addition, if the thermal stability of the acid-soluble collagens is improved, collagen from refiner discharge from Alaska pollock could be more effectively used. -
We prepared caviar analogs encapsulated by calcium-alginate gel membranes as a means to replace higher priced natural caviars. Processing the caviar analogs (beluga type) was optimized by response surface methodology with central composite design. Concentrations of sodium alginate (
$X_1$ ) and$CaCl_2\;(X_2)$ were chosen as the independent variables. In order to compare characteristics of the caviar analogs with the natural caviar, sphericity ($Y_1$ ), diameter ($Y_2$ ), membrane thickness ($Y_3$ ), rupture strength ($Y_4$ ), rupturing deformation ($Y_5$ ), and sensory score ($Y_6$ ) were used as the dependent variables. The sphericity of the caviar analogs showed a similar value to that of natural caviar (over 94%) in the range of independent variables. Generally, the$CaCl_2$ concentration ($X_2$ ) affected all dependent variables to a greater extent than the sodium alginate concentration ($X_l$ ), For the multiple response optimization of the 5 dependent variables ($Y_1,\;Y_2,\;Y_4,\;Y_5$ , and$Y_6$ ), the desirability function was defined as the following conditions: target values ($Y_1\;=\;100%,\;Y_2\;=\;3.0\;mm,\;Y_4\;=\;1,470\;g,\;Y_5\;=\;1.1\;mm,\;and\;Y_6\;=\;10\;points$ ). Membrane thickness ($Y_3$ ) was eliminated from the dependent variables for multiple response optimization because it could not be measured with an image analyzer. The values of the independent variables as evaluated by multiple response optimization were$X_1\;=\;-0.093$ (78%) and$X_2\;=\;-0.322$ (1.07%), respectively. -
Do, Jeong-Ryong;Kim, Ki-Ju;Kim, Hyun-Ku;Kim, Young-Myoung;Park, Yeung-Beom;Lee, Yang-Bong;Kim, Seon-Bong 565
This study was carried out to investigate an optimum condition for the high angiotensin-l converting enzyme (ACE) inhibitory activity and the yield on enzyme concentration, casein concentration, and hydrolysis time. The optimum condition was performed by response surface methodology for acquirement of casein hydrolysate of milk which shows high ACE inhibitory activity, Among 8 tested enzymes, Protamex showed the highest activation degree with 77.03 unit/g from casein. Their hydrolysis degrees of flovourzyme 500MG, protamex, mixture from 1% casein were 85.5, 88.5, and 93.5%, respectively. The ranges of enzyme concentration (0.25-1.25%), casein concentration (2.5-12.5%), and hydrolysis time (20-100 min) as 3 independent variables through preliminary experiments of the yield of casein hydrolysate and ACE inhibitory activity, and it shows optimum response surface at a saddle point. It shows enzyme concentration (0.64%), casein concentration (8.38%), and hydrolysis time (55.81 min) in the yield aspect and showed the highest activity at enzyme concentration (0.86%), casein concentration (5.97%), and hydrolysis time (63.86 min) in ACE inhibitory aspect. The$R^2$ value of a fitted optimum formula on the hydrolysis yield was 0.9751 as the significant level of 1%. The$R^2$ value of a fitted optimum formula on ACE inhibitory activity is 0.8398, and the significance is recognized in the range of 5%. -
The angiontensin converting enzyme (ACE) inhibitory peptides were separated from beef sarcoplasmic protein extract and their amino acid sequences were identified as GFHI, DFHINQ, FHG, and GLSDGEWQ. The 4 peptides were synthesized in a laboratory and the ACE inhibitory activities of pep tides was measured after 2 months of storage at
$4^{\circ}C$ under different pH conditions (6.0, 6.5, 7.0, 7.5, and 8.0) and the exposure of different temperatures (70, 80, 90, and$100^{\circ}C$ ) for 20 min to evaluate industrial use. No significant difference was detected by pH and temperature abuse for 20 min during storage. When the synthetic peptides were digested by pepsin, trypsin, and chymotrypsin, the ACE inhibitory activity was not changed. These results indicated that the 4 synthetic peptides with ACE inhibitory activity were pH-stable, heat-stable, and resistant to proteinases in gastro-intestinal tracts. Therefore, those 4 peptides can be used as a source for functional food product with various applications. -
The effects of temperature and Korean bramble (Rubus coreanum Miquel) tissue concentrate on heterocyclic aromatic amine (HAA) formation in fried ground beef patties were investigated. Various amounts of Korean bramble tissue (4.0, 7.0, and 11.0%, w/w) were added to ground beef patties were fried at 2 different temperatures (190 and
$225^{\circ}C$ ) for 10 min/side. It was observed in the fried ground beef patties fried at$190^{\circ}C$ with the addition of 11.0%(w/w) Korean bramble that the mutagenicity decreased by 64%, and formation of 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) and 2-amino-I-methyl-6-phenylimidazo[4,5-b]-pyridine(PhIP) reduced by 55 and 86%, respectively. Although no difference in total mutagenicity was shown in patties fried at$225^{\circ}C$ with the addition of 4.0, 7.0, and 11.0%(w/w), different levels of reduction of PhIP formation in patties fried at$225^{\circ}C$ with the addition of 4.0, 7.0, and 11.0%(w/w) were shown 49, 63, and 75%, respectively. -
Phytase activity was examined with various bifidobacterial strains cultured statically in MRS broth at
$37^{\circ}C$ for 48 hr. Seven Bifidobacterium species showed mostly an intracellular phytase activity, though their specific activities were very low. The highest specific activity was found in Bifidobacterium animalis B33 strain, among 7 bifidobacteria tested. The specific activity was highest during the exponential growth phase. Carbohydrates and the concentration of phosphorus sources had an effect on the phytase activity and bacterial growth. Glucose was the most favorable carbohydrate for the phytase activity. Phytate inhibited the cell growth, and phytase activity decreased with increase of phytate concentration. The phytase activity was even higher in the static microaerophilic growth than that in anaerobic state, despite the stimulated growth in anaerobic growth. The optimal pH ranges were comparatively broad, but the optimal temperatures were$50^{\circ}C$ for all tested strains. The phytase activity was most active at pH 6.5 and$50^{\circ}C$ for B. animalis B33 strain. -
Han, Kyu-Ho;Ohba, Kiyoshi;Lee, Chi-Ho;Shimada, Ken-Ichiro;Sekikawa, Mitsuo;Fukushima, Michihiro 584
The effect of water extract of adzuki beans on acetaminophen-altered lipid metabolism was examined in rats. Control group of rats was fed a basal diet, another group of rats was fed 0.5% acetaminophen (APAP group), and a third group of rats was fed 0.5% acetaminophen plus 5% adzuki bean extract (ABE group) for 4 weeks. Serum total and HDL cholesterol levels in the APAP group were significantly lower than those in the control and ABE groups. Hepatic cholesterol$7{\alpha}-hydroxylase$ and fatty acid synthase mRNA levels in the APAP and ABE groups were significantly higher and lower than in the control group, respectively. Hepatic 3-hydroxy-3-methylglutaryl-coenzyme A reductase mRNA level in the APAP group was significantly lower than in the control group, whereas that in the ABE group was significantly higher than in the APAP group. These results indicate that adzuki bean extract may improve the acetaminophen-altered serum lipid metabolism in rats. -
The textural properties of doughs mixed with L-ascorbic acid (AA), trypsin hydrolyzed gluten peptide (THGP), and a mixture of AA-THGP were investigated using texture analyzer under the fermentation of the full formula and the freezing process. The full formula dough (FFD) required a shorter mixing time than the flour and water formula dough (FWD). The maximum resistance (Rmax) values of both the unfrozen and frozen doughs were lower for the FFD. The effects of AA and THGP additions were not significant (p<0.01) in FFD, however, they were significant in FWD. The freezing effect was significant (p<0.0001) for FFD, indicating that yeast fermented dough was much more sensitive to damage from freezing, which subsequently affected dough strength. Additions of AA (p=0.0026) and THGP (p=0.0097) had a significant effect on the extensibility (E-value) of unfrozen FWD, where THGP increased and AA decreased the E-value. However, freezing did not significantly effect the extensibilities of FWD (p=0.64) or FFD (p=0.21). The area of FFD was lower than the area of FWD for both the unfrozen and frozen doughs. However, the frozen dough mixed with THGP alone had the largest area overall. The addition of additives did not result in significantly different (p<0.01) areas under the curve, except in the frozen FFD. Freezing caused a statistically significant difference in the area of FWD (p=0.0045).
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Jin, Cheng-Hao;Yang, Ung;Kim, Song-Hee;Ryu, Jae-Won;Lee, Jae-Chang;Lee, Dong-Seok;Lee, Tae-Hoon 594
In this study, we evaluated whether the oral administration of chondroitin from the cartilage of Raja kenojei is effective on the progression of rheumatoid arthritis (RA), using collagen-induced arthritic (CIA) mice. Arthritis development was delayed dose-dependently in the chondroitin-treated groups. The pre- and late-treated groups receiving 1,000 mg/kg of chondroitin had clinical scores that were reduced significantly by 56.9 (p<0.05) and 43.3% (p<0.05), respectively, compared to the vehicle-treated groups. Hematoxylin eosin staining and X-ray radiography showed that the chondroitins reduced the infiltration of inflammatory cells and prevented joint destruction of the knee and paw. Reverse transcription-polyerase chain reaction analysis revealed that chondroitin administration inhibited the expressions of tumor necrosis$factor-{\alpha}$ ($TNF-{\alpha}$ ),$interlukin-1{\beta}$ ($IL-1{\beta}$ ), and$interferon-{\gamma}$ ($IFN-{\gamma}$ ) in joints more than the administration of vehicle. Chondroitin treatment also decreased the production of rheumatoid factors (RF), IgG and IgM, in the serum of CIA mice. These results indicate that chrondroitin administration has a protective effect involving the inhibition of pro-inflammatory cytokine production in CIA mice. -
In this study, we first prepared 3 kinds of powders with different molecular masses from the crude protein-bound polysaccharide extract of Agraricus blazei Murill through ultrafiltration, followed by spray-drying. Then, the antitumor activities of the powders were analyzed. Size exclusion chromatography coupled with a multi-angle laser-light-scattering system showed the 3 powders had the following molecular ranges: below 10 kDa (SD-1), 10 to 150 kDa (SD-2), and above 150 kDa (SD-3), representing peak molecular weights of
$8.26{\times}10^3,\;9.65{\times}10^4$ , and$5.94{\times}10^6\;g/mol$ , respectively. All the powders stimulated macrophage RAW264.7 cells to produce nitric oxide, of which SD-2 and SD-3 were superior to the crude extract powder (CP-SD), while SD-1 showed the lowest activity. Similar results were found for their cytotoxicities against human cancer cell lines (A549, MCF-7, and AGS), where the highest activity was obtained with the SD-2 treatment for 72 hr at$1,000\;{\mu}g/mL$ . The MCF-7 cell line was less sensitive to the powders than the other cells. From this research we found that ultrafiltration, in combination with spray-drying, is applicable for preparing protein-bound polysaccharide powders with higher antitumor activities. -
The effects of lactic acid fermented yam yogurt (Yam/YG) on colon mucosal tissue were investigated in a loperamide-induced constipation rat models. Sprague-Dawley rats were fed for 6 weeks with 3 types of diets (normal, supplemented with lactic acid bacteria, and supplemented with Yam/YG), and were then administered loperamide intraperitoneally twice daily for 5 days. Administration of loperamide decreased fecal excretion and the moisture content of feces with increasing of numbers of pellets in the colon. On the histopathologic findings from hematoxylin and eosin (H& E) and alcian blue stainings, supplementation with Yam/YG resulted in the recovery of depleted goblet cells and mucin, and increased the numbers of Ki-67 positive cells, indicating restoration of colonic mucosa through cell proliferation and crypt regeneration against damages observed in crypt epithelial cells of loperamide-induced rats. These results indicate that Yam/YG improves evacuation and mucus production in the gastrointestinal tracts of constipated-induced rats.
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Dynamic rheological properties of honeys with invert sugar at different mixing ratios of honey and invert sugar (10/0, 812, and 6/4 ratios) were evaluated at various low temperatures (-15, -10, -5, and
$0^{\circ}C$ ) using a controlled stress rheometer for small-deformation oscillatory measurements. Honey-invert sugar mixtures displayed a liquid-like behavior, with loss modulus (G") predominating over storage modulus (G') (G">>G'), showing the high dependence on frequency (${\omega}$ ). The magnitudes of G' and G" increased with a decrease in temperature while their predominant increases were noticed at -10 and$-15^{\circ}C$ . The greater tan${\delta}$ values were found at higher temperature and ratio of honey to invert sugar, indicating that the honey samples at subzero temperatures become more viscous with increased ratio of honey to invert sugar and temperature. The time-temperature superposition (TTS) principle was used to bring G" values at various temperatures together into a single master curve. The TTS principle was suitable for the honey samples in the liquid-like state. The progress of viscous property (G") was also described well by the Arrhenius equation with high determination coefficients ($R^2=0.99$ ). Dynamic rheological properties of honey samples seem to be greatly influenced by the addition of invert sugar. -
Commercially packed kimchi products from 6 different manufacturers, which are exported overseas as well as sold domestically, were analyzed to determine their microorganism distributions and presence of pathogenic bacteria. All samples showed decreasing pH levels (from 5.7-6.2 to 3.9-4.3) and increasing titratable acidities (from 0.3-0.4 to 0.8-1.2%) during 15 days of storage at
$4^{\circ}C$ . Total bacterial counts ranged from$2.1{\times}10^5-1.9{\times}10^6\;CFU/mL$ in the initial kimchi samples, and then increased to$1.1{\times}10^8-1.8{\times}10^9\;CFU/mL$ . The coliform numbers decreased from approximately$2.5{\times}10^2-1.7{\times}10^4\;CFU/mL$ to zero. Major foodborne pathogens such as Salmonella spp., Staphylococcus aureus, Escherichia coli O157:H7, Listeria monocytogenes, Bacillus cereus, Yersinia enterocolitica, and Shigella spp. were not detected in any of the samples. However, 2 out of the 6 samples carried E. coli, emphasizing the need for improved hygiene practice. Interestingly, Hafnia alvei, belonging to the Enterobacteriaceae family, was isolated in all of the samples. Further study is needed on this newly reported bacterium in kimchi. -
Staphylococcus aureus in Korean kimbab rolls was monitored seasonally in 4 major cities of Korea to investigate the risk of S. aureus in a pre-prepared meal. Thirty-five (28.6%) of 105 kimbab rolls purchased in winter were contaminated with S. aureus with an average level of 2.6 log CFU/g. Thirty-six (33.0%) of 109 kimbab rolls purchased in summer and autumn were contained S. aureus with an average level of 2.9 log CFU/g. Kimbab purchased in snack bars showed higher S. aureus contamination rates with the maximum level of 4.7 log CFU/g than that purchased in convenience stores. Of the raw materials in kimbab, uncooked perilla leaf had the highest contamination rate of S. aureus. Less than 50% of S. aureus isolated from kimbab produced enterotoxin and most of the staphylococcal enterotoxin produced by S. aureus in kimbab was type A.
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Lee, Eui-Soo;Jeon, Jong-Youn;Yu, Long-Hao;Choi, Ji-Hun;Han, Doo-Jeong;Choi, Yun-Sang;Kim, Cheon-Jei 626
Pre-rigor bovine sternomandibularis muscles were frozen at 3 hr postmortem thawed at various temperatures (18, 2, and$-2^{\circ}C$ ), and then meat quality and sensory properties were compared with those in chilled muscle (control). The meat thawed at$18^{\circ}C$ had lower ultimate pH, water holding capacity, and sensory scores and higher muscle shortening, thaw drip loss, and shear values than those of the other samples. The samples thawed at$-2^{\circ}C$ had significantly lower muscle shortening and higher sensory scores in tenderness and juiciness than those thawed at 18 and$2^{\circ}C$ . Muscle shortening, pH, WHC, shear values, and sensory properties were not significantly different between control and sample thawed at$-2^{\circ}C$ . By holding at$-2^{\circ}C$ , thaw shortening was prevented and tender meat comparable to the chilled meat was obtained. These results indicate that thaw shortening can be largely eliminated if the frozen pre-rigor muscle is thawed at$-2^{\circ}C$ . -
Son, Dong-Wook;Lee, Pyeong-Jae;Lee, Jong-Seok;Lee, Sang-Hyun;Choi, Sang-Yoon;Lee, Jong-Won;Kim, Sun-Yeou 632
This study examined the neuroprotective effect of scopoletin from Angelica dahurica against oxygen and glucose deprivation-induced neurotoxicity in a rat organotypic hippocampal slice culture. Scopoletin reduced the propidium iodide (PI) uptake, which is an indication of impaired cell membrane integrity. In addition, it inhibited the loss of NeuN, which represents the viability of neuronal cells. The results suggests that scopoletin from A. dahurica protects neuronal cells from the damage caused by oxygen and glucose deprivation. -
Shin, Yoo-Su;Lee, Min-Jeong;Bang, Kyong-Hwan;Kim, Seon-Young;Lee, Sung-Sik;Hyun, Dong-Yoon;An, Tae-Jin;Cha, Seon-Woo;Seong, Nak-Sul 636
In order to investigate the major metabolite patterns of aged Panax ginseng C.A. Meyer roots, the ginsenoside contents for white ginseng roots of various ages were compared. The 1-year to 6-year old roots were extracted with methanol, and then the methanol-soluble metabolites were analyzed by high performance liquid chromatography (HPLC). The metabolite contents of the 1-year and 2-year roots, including the ginsenosides and minor components, were not different, but the$Rg_1$ , Re, and Rc ginsenoside contents between the 2-year and 3-year roots showed significant differences.$Rg_1$ and Rc increased significantly in the 1-year to 2-year roots, and Re increased significantly from the 3-year root age. Rd increased slightly until the 2-year age and decreased from the 3-year age. Based on the ginsenoside distributions and contents at various root ages, we have suggested 2 biogenesis schemes using the ginsenosides that have been isolated from the roots of P. ginseng so far. -
Anti-Proliferative and Anti-Carcinogenic Enzyme-inducing Activities of Delphinidin in Hepatoma CellsJang, Chan-Ho;Lee, In-Ae;Lim, Hyun-Ae;Kim, Ju-Ryoung;Ha, Young-Ran;Yu, Hoon;Sung, Mi-Kyung;Kim, Jong-Sang 641
Delphinidin, an aglycone form of anthocyanins, was demonstrated to have anti-carcinogenic potential. The compound at$50\;{\mu}g/mL$ caused a significant increase of quinone reductase activity, an anti-carcinogenic marker enzyme, in mouse hepatoma cell lines (Hepa1c1c7 and BPRc1). Delphinidin enhanced the expression of other detoxifying or antioxidant enzymes including glutathione s-transferase, gamma-glutamylcysteine synthetase, heme oxygenase 1, and glutathione reductase. It suppressed the proliferation of murine hepatoma cells in a dose-dependent manner, with approximately$IC_{50}$ of$70\;{\mu}g/mL$ . These results suggest that delphinidin might be useful for cancer prevention. -
The effect of the addition of 2 kinds of chemically modified starches (the anti-caking agents; tapioca starch and com starch) on caking of ramen soup was observed using a low-resolution proton-pulsed nuclear magnetic resonance (NMR) technique. After storing ramen soup samples with diverse compositions of modified starch at 20-40% relative humidity for 4 weeks, changes in the spin-spin relaxation time constant (
$T_2$ ) were measured as a function of temperature.$T_2-Temperature$ curves for ramen soup containing modified starches showed that the caking initiation temperature (glass transition temperature) was increased by$5^{\circ}C$ following the addition of only 0.5% modified cornstarch. The results indicate that the modified com starch used in this study would be an effective anti-caking agent for ramen soup, thus prolonging the shelf life of the product. -
Many vegetables contain oxalate at various levels depending on their type and family. Oxalate is known to reduce mineral bioavailability from foods. The following study was conducted to determine soluble and total oxalate contents in 32 plant samples commonly consumed in Korea using high-performance liquid chromatography (HPLC). Chard, amaranth, and spinach contained total oxalate of >1,000 mg/100 g. Approximately 45% of the oxalate in amaranth is insoluble, whereas 74.46 and 92.45% of the oxalates in chard and spinach, respectively, was soluble oxalates, which may be removed by blanching. Eggplant, carrot, leak, ginger root, spinach, burdock, and sweet pepper contained more than 90% soluble oxalate in total oxalate content. However, all oxalates detected in lettuce and celery were insoluble. Oxalate was not detected in shepherd's purse, bellflower root, garlic, radish root, broccoli, cabbage, onion, lotus root, adlay, cucumber, kale, and pumpkin. These observations provide useful information needed for selection of vegetables.
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Paik, Hyun-Dong;Kim, Il-Gi;Lee, Jin-Hyoung;Lee, Jang-Hyun;Park, Kyu-Yong;Ji, Geun-Eog;Jin, Tae-Eun;Rhim, Seong-Lyul 655
Bacillus polyfermenticus SCD was transformed by the recombinant shuttle vector for Bacillus and Escherichia coli containing 3 antibiotic resistant genes and an${\alpha}$ -amylase gene from Bifidobacterium adolescentis Int57. The${\alpha}$ -amylase gene fused to a secretion sequences was expressed under the control of the promoter of amylase gene from B. subtilis var. natto. The recombinant plasmid was maintained stably in the transformants producing the${\alpha}$ -amylase. The enzyme was secreted to outside of the cell and showed the similar enzyme activity as that of Bacillus subtilis BD170 under the same conditions of pH and growth temperature. Because of the relatively easy transformation and the secretion of the enzyme, the transformants of B. polyfermenticus SCD may give a new strategy in the production of foreign genes. -
In order to determine the optimal storage conditions of Capsosiphon fulvescens (maesaengi), 2 types of wash solutions (distilled water and seawater) and storage temperatures (-20 and
$-80^{\circ}C$ ) were evaluated for the effectiveness of microbial growth inhibition and the changes of texture, color, and proximate composition. Thawed samples that had been washed with seawater and stored at$-20^{\circ}C$ for 50 days showed a 1.1-fold increase in hardness compared to the initial hardness of the sample ($1.9{\times}10^5\;dyne/cm^2$ ). There was no change in moisture, ash, or crude lipid during storage at -20 and$-80^{\circ}C$ for 60 days, while there was a$1{\pm}0.2%$ decrease in crude protein content for the control during storage at both -20 and$-80^{\circ}C$ for 60 days. In conclusion, the recommended optimal storage conditions for retaining the quality of C. fulvescens are: temperatures at or below$-20^{\circ}C$ and washings with either distilled water or seawater for inhibiting microbial growth, temperatures at or below$-20^{\circ}C$ and a washing with seawater to prevent reductions in hardness, and a temperature of$-80^{\circ}C$ and washings with either distilled water or seawater to protect against color changes.