• Korean Journal of Food Science and Technology
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• v.42 no.2
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• pp.155-159
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• 2010

The antimicrobial activity of Sargassum fulvellum (SF) was investigated using the agar diffusion assay and MIC test. In addition, the stability of this activity under extreme heat and pH conditions was examined. The SF ethanol extract was shown to display strong antimicrobial activities against B. subtilis, C. perfringens, L. plantarum, S. aureus, L. monocytogenes, S. cerevisae and C. tropicalis in the agar diffusion assay at the concentration of 4 mg/mL. The MIC value of the SF ethanol extract against the tested microbes ranged from 0.05 to 0.0063%. In the heat and pH stability test, the antimicrobial activity of the SF ethanol extract was not altered when the temperature was maintained at $121^{\circ}C$ for 15 min, and it was also not affected in the pH range of 2-10. These results suggest that the SF ethanol extract is highly stable against drastic changes in temperature and pH.

• Journal of Life Science
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• v.30 no.3
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• pp.304-312
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• 2020

Agarase can be used in the field of basic science, as well as for production of agar-derived high-functional oligosaccharides and bioenergy production using algae. In 2012, we summarized the classification, origin, production, and applications of agar. In this paper, we briefly review the literature on the recombinant expression of agarases from 2012 to the present. Agarase genes originated from 19 genera, including Agarivorans, Flammeovirga, Pseudoalteromonas, Gayadomonas, Catenovulum, Microbulbifer, Cellulophaga, Saccharophagus, Simiduia, and Vibrio. Of the 47 recombinant agarases, there were only two α-agarases, while the rest were β-agarases. All α-agarases produced agarotetraose, while β-agarases yielded many neoagarooligosaccharides ranging from neoagarobiose to neoagarododecaose. The optimum temperature ranged between 25 and 60℃, and the optimum pH ranged from 3.0 to 8.5. There were 14 agarases with an optimum temperature of 50℃ or higher, where agar is in sol state after melting. Artificial mutations, including manipulation of carbohydrate-binding modules (CBM), increased thermostability and simultaneously raised the optimum temperature and activity. Many hosts and secretion signals or riboswitches have been used for recombinant expression. In addition to gene recombination based on the amino acid sequence after agarase purification, recombinant expression of the putative agarase genes after genome sequencing and metagenome-derived agarases have been studied. This study is expected to be actively used in the application fields of agarase and agarase itself.

• Culinary science and hospitality research
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• v.19 no.3
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• pp.46-56
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• 2013

This study investigates the quality characteristics of Sikhye, a Korean traditional drink, made with different amounts of Monascus anka rice, or red yeast rice, and the results are as follows. During the saccharification process of red yeast rice, there was not significant change in pH, and its sugar content increased. It revealed that the optimal hours of saccharification for making Sikhye were four or five hours, which showed the highest in $^{\circ}Brix$. PH decreased significantly with increasing amounts of red yeast rice, and there was no change in sugar content and reducing sugar. Chromaticity L values decreased with increasing amounts of red yeast rice, and a value, b value and the turbidity increased. DPPH free radical scavenging activity of the samples showed significant differences in the samples with high scores as the amounts of red yeast rice increased. As a result of measuring the total microorganism number of the sample stored at $4^{\circ}C$, storability was improved with increasing amounts of red yeast rice. Preference was high in the order of 40%, 50%, 30%, 20%, 0%, and 10%, and the optimal amount of red yeast rice was less than 40-50%. Adding red yeast rice showed high scores in the sensory test, showing red color in Sikhye. In addition, its antioxidative activity effect and microbial growth inhibitory activity were considered to improve storability and preference.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.12
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• pp.1954-1958
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• 2014

The feasibility of incorporating Cynanchi wilfordii powder as a value-added food ingredient in convenient food products was investigated using yanggaeng as a model system. C. wilfordii powder was incorporated into yanggaeng at 0, 2, 4, 6, and 8% weight amounts based on total weight of cooked white bean and C. wilfordii powder. pH increased significantly, and moisture content ranged from 45.40% to 47.40% with increasing levels of C. wilfordii powder (P<0.05). In terms of color, lightness, redness, and yellowness increased significantly (P<0.05) with increasing levels of C. wilfordii powder. Hardness significantly decreased with higher amounts of C. wilfordii powder (P<0.05). Total polyphenol content and DPPH radical scavenging activity were significantly influenced by addition of C. wilfordii powder, and they increased significantly as C. wilfordii powder concentration increased (P<0.05). Finally, consumer acceptance test indicated that the highest levels of C. wilfordii powder (8%, w/w) had considerable adverse effects on consumer preferences in general. In contrast, yanggaengs with moderate levels of C. wilfordii powder (2%, w/w) are recommended (with respect to overall preference score) to take advantage of the functional properties of C. wilfordii powder without sacrificing consumer acceptability.

• Food Science and Preservation
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• v.24 no.5
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• pp.707-713
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• 2017

The objective of this study was to select yogurt starter from Korean traditional fermented foods. The 2 strains (KM24, KM32) among 50 strains of isolated lactic acid bacteria selected as starter based on milk clotting ability, antimicrobial activity against various pathogens, tolerance in artificial gastric and bile juice and growth in 10 % skimmed milk. The strains were identified as Lacobacillus plantarum (KM32) and Pediococcus pentosacesus (KM24) by 16S rRNA gene sequencing. Viable cell number of yogurt fermented with mixed strains (KM24 and KM32) was 9.66 log CFU/mL after fermentation for 48 h and maintained $10^9CFU/mL$ during fermentation for 72 h at $37^{\circ}C$. The pH and titratable acidity of mixed cultured yogurt were 4.25% and 0.83% after fermentation for 48 h at $37^{\circ}C$, respectively. The physico-chemical characteristics of mixed cultured yogurt after fermentation for 48 h were $38.45{\mu}g/mL$ (polyphenol content), 48.57% (DPPH radical scavenging activity) and 465.40 cp (viscosity), respectively. The mixed cultured yogurt maintained $10^9CFU/mL$ of lactic acid bacteria during storage 10 days at $4^{\circ}C$. The viable cell number of yogurt prepared with mixed culture(KM32+KM24) maintained higher and than that of control (L. casei) during storage. These results indicated the potential use of selected strains (KM32+KM24) isolated from kimchi as a yogurt starter with strong acid tolerance and probiotics properties.

• Journal of Bio-Environment Control
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• v.28 no.1
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• pp.38-45
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• 2019

Recycling of drained nutrient solution in hydroponic cultivation of horticultural crops is important in the conservation of the water resources, reduction of production costs and prevention of environmental contamination. Objective of this research was to obtain the fundamental data for the development of a recirculation system of hydroponic solution in semi-forcing cultivation of 'Bonus' tomato. To achieve the objective, tomato plants were cultivated for 110 days and the contents of inorganic elements in plant, supplied and drained nutrient solution were analyzed when crop growth were in the flowering stage of 2nd to 8th fruiting nodes. The T-N content of the plants based on above-ground tissue were 4.1% at the flowering stage of 2nd fruiting nodes (just after transplanting), and gradually get lowered to 3.9% at the flowering stage of 8th fruiting nodes. The tissue P contents were also high in very early stage of growth and development and were maintained to similar contents in the flowering stage of 3rd to 7th fruiting nodes, but were lowed in 8th node stages. The tissue Ca, Mg and Na contents in early growth stages were lower than late growth stages and the contents showed tendencies to rise as plants grew. The concentration differences of supplied nutrient solution and drained solution in $NO_3-N$, P, K, Ca, and Mg were not significant until 5 weeks after transplanting, but the concentration of those elements in drained solution rose gradually and maintained higher than those in supplied solution. The concentrations of B, Fe, and Na in drained solution were slightly higher in the early stages of growth and development and were significantly higher in the mid to late stages of growth than those in supplied solution. The above results would be used as a fundamental data for the correction in the inorganic element concentrations of drained solution for semi-forcing hydroponic cultivation of tomato.

• The Korean Journal of Physiology and Pharmacology
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• v.2 no.4
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• pp.521-527
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• 1998

An important property of the intestine is the ability to secrete fluid. The intestinal secretion is regulated by a number of substances including vasoactive intestinal peptide (VIP), ATP and different inflammatory mediators. One of the most important secretagogues is adenosine during inflammation. However, the controversy concerning the underlying mechanism of adenosine-stimulated $Cl^-$ secretion in intestinal epithelial cells still continues. To investigate the effect of adenosine on $Cl^-$ secretion and its underlying mechanism in the rabbit colon mucosa, we measured short circuit current ($I_{SC}$) under automatic voltage clamp with DVC-1000 in a modified Ussing chamber. Adenosine, when added to the basolateral side of the muocsa, increased $I_{SC}$ in a dose-dependent manner. The adenosine-stimulated $I_{SC}$ response was abolished when $Cl^-$ in the bath solution was replaced completely with gluconate. In addition, the $I_{SC}$ response was inhibited by a basolateral Na-K-Cl cotransporter blocker, bumetanide, and by apical $Cl^-$ channel blockers, dephenylamine-2-carboxylate (DPC), 5-nitro-2-(3-phenyl-propylamino)-benzoate (NPPB), glibenclamide. Amiloride, an epithelial $Na^+$ channel blocker, and 4,4-diisothiocyanato-stilbene-2,2-disulphonate (DIDS), a $Ca^{2+}-activated$ $Cl^-$ channel blocker, had no effect. In the mucosa pre-stimulated with forskolin, adenosine did not show any additive effect, whereas carbachol resulted in a synergistic potentiation of the $I_{SC}$ response. The adenosine response was inhibited by 10 ${\mu}M$ H-89, an inhibitor of protein kinase A. These results suggest that the adenosine-stimulated $I_{SC}$ response is mediated by basolateral to apical $Cl^-$ secretion through a cAMP-dependent $Cl^-$ channel. The rank order of potencies of adenosine receptor agonists was $5'-(N-ethylcarboxamino)adenosine(NECA)＞N^6-(R-phenylisopropyl)adenosine(R-$ PIA)＞2-[p-(2-carbonylethyl)-phenyl-ethylamino]-5'-N-ethylcarboxaminoadenosine(CGS21680). From the above results, it can be concluded that adenosine interacts with the $A_{2b}$ adenosine receptor in the rabbit colon mucosa and a cAMP-dependent signalling mechanism underlies the stimulation of $Cl^-$ secretion.

• Horticultural Science & Technology
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• v.29 no.5
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• pp.494-499
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• 2011

Cold pretreatment, washing medium and composition of nutrient media may have marked effects on microspore embryogenesis. When microspores isolated from radish (Raphanus sativus L. cv. Gwanhun) flower buds were washed with Nitsch & Nitsch (NLN) medium liquid medium containing $130g{\cdot}L^{-1}$ sucrose (NLN-13), yields of microspore-derived embryos were greater than when using B5 liquid medium containing $130g{\cdot}L^{-1}$ sucrose. Microspore viability is known to decrease rapidly with storage; however, in this experiment, microspore viability was maintained for 24 h at $4^{\circ}C$ without media. Among the various medium concentrations used ($0.25{\times}$, $0.5{\times}$, $1.0{\times}$, $2.0{\times}$, and $4.0{\times}$ NLN liquid medium), $0.5{\times}$ NLN liquid medium induced the most efficient formation of microspore-derived embryos. In addition, microspore-derived embryos yields were greater when microspores were cultured in $0.5{\times}$ NLN liquid medium supplemented with $0.25{\times}$, $0.5{\times}$, and $1.0{\times}$ NLN microelements, compared to medium not supplemented with microelements. In this study, the highest yield of microspore-derived embryos was observed when the microspores derived from flower buds were washed using NLN-13 liquid medium and then cultured on $0.5{\times}$ NLN liquid medium supplemented with $0.25{\times}$ NLN microelements, followed by incubation at $25^{\circ}C$ for 30 days.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.3
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• pp.348-355
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• 2000

The study was conducted to determine physicochemical parameters in various physical fractions (linter, hull, kernel, oil and meal) of cottonseed of different varieties (MNH 147, CIM 240, NIAB 78, FH 87, CIM 109, MNH 93, FH 682, GOHAR 87, SLS 1 and B 557). Average components of linter, hull, and kernel in different varieties of cotton were 12.21, 28.24 and 70.42%, respectively. Average percentage of meal and oil was 48.97 and 22.09% in seed, and 69.28 and 30.72% in kernel, respectively. Maximum percentage of meal was recovered from variety CIM 240 and lowest in variety CIM 109. Statistical analysls revealed variety differences (p<0.05) in seed and it's components. Average contents of crude protein, crude fiber and ash was 22.31, 17.74 and 4.27% in seed, 2.85, 56.50 and 2.61% in hull; 32.62, 3.45 and 4.01 % in kernel; 47.15, 5.00 and 5.78% in meal, respectively. Average contents of Ca, p, Mg, K, Na and Cl were 0.09, 0.22, 0.26, 0.65, 0.009 and 0.035% in seed; 0.12, 0.07, 0.09, 0.51, 0.020 and 0.034% in hull and 0.16, 0.59, 0.32, 1.01, 0.03 and 0.07% in meal of different varieties of cotton, respectively. Fe, Zn, Cu and Mn were 141.35, 24.55, 186.50 and 27.12 mg/kg in seed; 158.48, 2.06, 74.60, and 22.17 mg/kg in hulls; and 167.62, 20.30, 185.83 and 20.67 mg/kg in meal, respectively. Significant varietal differences were observed in proximate composition and mineral contents of cottonseeds and derived products. Cottonseeds and their products of varieties FH 87, CIM 109 and MNH 93 showed higher nutrient density while lower was observed in varieties CIM 240, SLS I and FH 682.

• Journal of the East Asian Society of Dietary Life
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• v.14 no.4
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• pp.387-396
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• 2004

It was investigated to study the sensory and physicochemical properties of chicken consomme made with different boiling time(1, 2, 3, and 4 hr). The sensory properties were evaluated with respect to both the acceptability (color, smell, mouthfeel, taste, overall acceptability) and intensity characteristics (color, smell, clarify, taste). From the results, the 3hr treatment was most favored for smell, mouthfeel, taste and overall acceptability, from the sensory evaluation tests. According to a quantitative descriptive analysis of the sensory evaluation for the treatments, the color and smell showed higher scores by increasing the boiling time. Whereas, in clarify and taste, the 3hr treatment showed the highest values. As for the physicochemical characteristics, the pH was increased with increasing boiling time. The reducing sugars, turbidity and viscosity increased with increasing boiling time. The colorimetric lightness values L decreased, and redness a, yellowness b and color difference values ΔE increased with increasing boiling time. There were 18 free amino acids indentified ； the glutamic acid, alanine, arginine and lysine were high in the free amino acid of the chicken consomme made with different boiling times. There were 3 free sugar indentified, glucose, fructose and sucrose. The free amino acid and free sugars contents increased with increasing boiling time. There were changes in the mineral contents of the chicken consomme made with different boiling time ; with high K, Na, P, Mg, Ca and Fe contents. The mineral contents increased with increasing boiling time. Especially, the 3hr treatments was more highly increased than rest of the treatments in all characteristics. The results showed the chicken consomme made by boiling far 3hr was the most preferably in the sensory and physicochemical quality.