• Korean Journal of Food Science and Technology
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• v.30 no.3
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• pp.608-614
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• 1998

In order to establish the scientific foundations for the production of Korean traditional kanjang (soy sauce) in a semi-pilot scale, meju preparation and kanjang mashing methods were investigated. Two types of meju, one that was prepared by conventional method (CM-meju) and the other that prepared by modified conventional method (MCM-meju), were made and compared their characteristics. The former made of cooked and crushed soybean with a brick shape was fermented at $15{\sim}20^{\circ}C\;and\;40{\sim}50%$ relative humidity (RH) for 30 days in koji room and the latter was fermented at $25{\sim}30^{\circ}C\;and\;80{\sim}90%$ RH seemingly being optimum for the growth of meju-organisms for the same period. The quality of MCM-meju as a raw material for the kanjang preparation was considered to be superior to that of CM-meju as the higher soluble nitrogen and total free amino acids content, the major factor for the evaluation of the quality of meju, were found in the former although the higher total nitrogen content and lower % weight loss were observed in the latter during meju preparation process. The quality of MCM-kanjang with higher total nitrogen, free amino acids, free sugars and the lower residual nitrogen content in cake after separation of kanjang was also found to be superior to that of CM-kanjang in sensory evaluation results.

• Journal of the Korean Society of Food Science and Nutrition
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• v.13 no.1
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• pp.97-106
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• 1984

The Antarctic krill, Euphausia superba, is drawing attention over the world as the largest source of unutilized proteins in the ocean. For the use of krill as a human food, processing conditions of krill sauce by autolysis and/or commercial proteolytic enzyme digestion were examined. The krill was chopped and mixed with equal weight of water, and hydrolyzed by autolysis and/or commercial proteolytic enzyme digestion. The optimal conditions for hydrolysis of krill were $52.5^{\circ}C$, pH 7.0-7.5, 3 hours by autolysis, $52.5^{\circ}C$, pH 6.3, 3hours by bromelain (0.5 %) digestion, and $52.5^{\circ}C$, pH 7.0-7.5, 3 hours by commercial complex enzyme (5 %) digestion, respectively The maximum hydrolyzing rate of protein were 83.2 % by autolysis, 89.7 % by bromelain digestion, 92.7 % by commercial complex enzyme digestion. After krill meat hydrolyzed by autolysis at optimum condition, inactivated at $100^{\circ}C$ for 20 minutes and filtered with Buchner funnel. Two kinds of products were prepared with krill hydrolysate and preservatives: one contained 10 % of sodium chloride and 0.06 % of benzoic acid and the other 10 % of sodium chloride and 3 % of ethyl alcohol. These products were filled in the sterilized glass bottle and sealed. The pH, volatile basic nitrogen, amino nitrogen, color value (L, a and b values) and viable counts of bacteria were determined during storage at $37^{\circ}C$. The results showed that the products could be preserved in good condition during one month at $37^{\circ}C$. As a method to reduce the sodium level in krill sauce, it is convinced that sodium chloride could be replaced half in partially by potassium chloride. In the products prepared from krill by autolysis, bromelain or commercial complex enzyme digestion, hypoxanthine and 5'-IMP were abundant among the nucleotides and their related compounds as 15.3-20.4 ${\mu}mole/g$, dry solid, 2.2-2.5 ${\mu}mole/g$, dry solid, respectively. The abundant free amino acids were lysine, leucine, proline, alanine and valine. The contents of these amino acids were 67.4 %, 69.4 %, 69.8 % of the total free amino acids of each products. And TMAO, betaine and total creatinine were low in contents. The flavor of krill sauce prepared from krill by autolysis or enzyme digestion was not inferior to that of traditional Kerean soy sauce by sensory evaluation.

• Journal of Aquaculture
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• v.21 no.1
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• pp.26-33
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• 2008

This study investigated the synergistic effects of dietary supplementation of quartz porphyry(QP) and a laboratory developed feed stimulants, BAISM(BS) on growth performance and utilization as the additives for juvenile eel Anguilla japonica. Six isoenergetic experimental diets(18.2 kJ/g) were formulated to contain 50% crude protein, 15% lipid with or without dietary QP(Song-Gang stone, Davistone, Korea) and BS supplementation. QP and BS were provided at 0% in the control diet($Q_0B_0$) and at 0.7% QP+0% BS($Q_{0.7}B_0$), 0.7% QP+0.3% BS($Q_{0.7}B_{0.3}$), 0.7% QP+0.5% BS($Q_{0.7}B_{0.5}$), 0.7% QP+0.75% BS($Q_{0.7}B_{0.75}$) and 0.7% QP+1.0% BS($Q_{0.7}B_{1.0}$) in experimental diets on dry matter basis. After four weeks of adaptation, triplicate groups of 30 fish initially averaging $15{\pm}0.1g(mean{\pm}SD)$ were randomly distributed into each aquarium, and they were fed one of the experimental diets for 8 weeks. By the end of the feeding trial, weight gain(%), specific growth rate(%), feed efficiency(%) and protein efficiency ratio of fish fed diet $Q_{0.7}B_{0.5},\;Q_{0.7}B_{0.75}\;and\;Q_{0.7}B_{1.0}$, were significantly higher(P<0.05) than those of fish fed the other diets. But, $Q_{0.7}B_{0.5},\;Q_{0.7}B_{0.75}\;and\;Q_{0.7}B_{1.0}$ were no significant differences(P<0.05). In challenge test, fish were infected by intraperitoneal injection of 0.1 mL bacterial suspension with Edwardsiella tarda per fish after the feeding trial. As a result, fish fed QP and BS supplemented diets have a significantly higher cumulative survival rate than those of fish fed control diet(P<0.05). In conclusion, these results indicated that the optimum dietary supplementation level of QP and BS could be approximately 0.7% quartz porphyry+0.5% BAISM($Q_{0.7}B_{0.5}$) of diet based on WG, FER, SGR, PER, cumulative survival rate in juvenile eel A. japonica.

• Food Science and Preservation
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• v.14 no.3
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• pp.301-307
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• 2007

To efficiently use Korean mung beans, the functional characteristics of mung bean powder(A), unhydrolyzed mung bean flour(B), and mung bean flour hydrolyzed under optimum conditions(C), were compared. The contents of protein, fat, carbohydrate, ash, and water, did not vary greatly with different treatment methods. The color values of (B) and (C) were similar, while the L value of (A) was higher than those of the other samples. Thereducing sugar content of (C) was highest at 292.63 mg%, while the total phenol contents of (A) and (C) were similar at 38.63 mg% and 38.38 mg%, respectively. The molecular weight of (A) was under 17 kDa by SDS-PAGE, and was lower than the molecular weights of the other samples (B, C), which generally ranged from 17 kDa to 72 kDa. The free sugar content of (C) was highest at 1,125.16 mg%, while (A) and (B) yielded values of 86.36 mg% and 54.20 mg%, respectively. Total free amino acid contents were in the order(C)(B)(A), and were 22,116.35 mg%, 2,731.29 mg%, and 578.54 mg%, respectively. The amino acid content of (C) was 8,231.42 mg% and was higher than those of (A) or(B). The DPPH free radical scavenging abilities of (A) and (C) were high, at 62.1% and 57.63%, respectively, while (B) showed a lower value at 19.26%. Fibrinolytic activity was highest(24.01%) in (C), and was 20.69% in (A) and 18.06% in (B). The above results indicate that mung bean flour hydrolyzed under optimal conditions (C) had the highest functional and quality characteristics, in comparisonh with unhydrolyzed flour (B) and mung bean powder (A). Diverse applications of hydrolyzed mung bean flour are anticipated.

• Journal of Bio-Environment Control
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• v.21 no.4
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• pp.305-311
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• 2012

To investigate the influence electrical conductivity (EC) of nutrient solution and light intensity on growth of red leafy lettuce, fresh and dry weights, number of leave, chlorophyll concentration and production efficiency were evaluated through nutrient film technique system. The levels of EC were 0.5, 1.0, 1.5, 2.0, 3.0, and $6.0dS{\cdot}m^{-1}$, and those of light intensity were 120, 150, and $180{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$. Under photoperiod of 16 h/day, the temperature was maintained in the range of $20{\sim}25^{\circ}C$. Planting density was $10{\times}10cm$ (100 plants/$m^2$). When red leafy lettuce were grown in the EC range of $0.5{\sim}1.5dS{\cdot}m^{-1}$, the fresh and dry weights decreased as the EC levels and light intensity were lowered, however, Hunter's a value showed no significant differences among the treatments of EC and light intensity levels (Ex. 1). The fresh and dry weights and production efficiency ($g{\cdot}FW/kw$) were the highest in the treatment of $3.0dS{\cdot}m^{-1}$ and $180{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ when crops were grown under the EC range of EC $1.5{\sim}6.0dS{\cdot}m^{-1}$ (Ex. 2). But the fresh and dry weights, number of leaves, and production efficiency of $2.0dS{\cdot}m^{-1}$ were the highest when the light intensity was $180{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ (Ex. 3). The SPAD value increased gradually as EC levels were elevated. From the above results, we concluded that optimum levels of EC and light intensity were $2.0dS{\cdot}m^{-1}$ and $180{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, respectively, for production as well as production efficiency of red leaf lettuce in plant factory.

• Korean Journal of Weed Science
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• v.15 no.2
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• pp.166-174
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• 1995

This experiment was conducted to investigate a cause of summer depression of cool season turfgrass, using nine cultivars in warm season and twenty-eight cool season turfgrasses. Even though an average of apparent photosynthesis(APS) per fresh weight was 13.09 mg $CO_2$/g/h in warm season turfgrass and 7.75 mg $CO_2$/g/h in cool season turfgrass, the Creeping bentgrass in cool season type was higher than Kikuyugrass and Bahiagrass in warm season type. The optimum temperature for the heighest APS was $30^{\circ}C$ in warm season type and $25^{\circ}C$ in cool season type. In $CO_2$ compensation point(CCP) as an index of dark respiration, it was higher in cool season turfgrass(75.6ppm) than warm season turfgrass(29.5ppm). In warm season type, even though the temperature increased from $25^{\circ}C$ to $40^{\circ}C$ the CCP was not increased. But the higher temperature rises the more increased CCP in cool season type. Dark respiration(DR) was higher in cool season type than warm season type under various temperature conditions, but the increasing ratio of DR with the temperature increment was not so much differed between two types.

• Journal of Plant Biotechnology
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• v.38 no.3
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• pp.221-227
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• 2011

This study was carried out to determine optimal medium conditions for mass propagation by bioreactor culture of ever-bearing strawberry (Fragaria ${\times}$ ananassa D.). Two different type of nitride were that mixed $NH_4NO_3$ and $KNO_3$ or added $KNO_3$ only. And nitride concentrations were at the 4 levels of $1/2{\times}$, $1{\times}$, $2{\times}$ and $3{\times}$ that was included $NH_4NO_3$ and $KNO_3$. Sucrose content ranged at 3 levels of $10g{\cdot}L^{-1}$, $20g{\cdot}L^{-1}$ and $30g{\cdot}L^{-1}$ and medium pH were at the 3 levels of 4.6, 5.6 and 6.6. In bioreactor culture, medium that are included $NH_4NO_3$ and $KNO_3$ together in MS medium was suitable for mass propagation. Medium EC rose rapidly when the nitride concentration was increased. For that reason, plantlet growth was inhibited. Shoots of nitride $1/2{\times}$ concentration was 10.8 ea and $1/2{\times}$ concentration was suitable for shoot propagation. Fresh weight of sucrose $30g{\cdot}L^{-1}$ was 3,101 mg which was heaviest and aerial and ground part were higher than the other concentration. Shoots were increased in proportion to the increasing concentration of sucrose. In the pH condition, from pH 5.6 to 6.8 were appropriate for the optimum growth of aerial and ground part of plant. From the results, in bioreactor culture for mass propagation, MS medium was suitable $1/2{\times}$ concentration that was included $NH_4NO_3$ and $KNO_3$ together, and added $30g{\cdot}L^{-1}$ of sucrose, and then adjusted pH between 5.6 and 6.6.

• Journal of Life Science
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• v.21 no.2
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• pp.309-315
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• 2011

Rice syrup meal (RSM) was enzymatically hydrolyzed using eight commercial proteases (Protamex, Neutrase, Flavourzyme, Alcalase, Protease M, Protease N, Protease A, Molsin F) for 4 hr at optimum pH and temperature. Proteolytic hydrolysates were examined in supernatant and precipitate using Lowry protein assay, semimicro Kjeldahl method and gravimetric method using weight difference before and after enzymatic hydrolysis. Although RSM contains a high amount of protein (71.2%), only a very small amount of protein was hydrolyzed. Two proteases (Protease M and Protease N) were found to be the most effective in the hydrolysis of RSM protein. In Lowry method, 57.5 and 59.0 mg protein/g RSM were hydrolyzed after Protease M and Protease N treatments, respectively. In gravimetric method, 80.0 and 85.4 mg protein/g RSM were hydrolyzed after Protease M and Protease N treatments. In Kjeldahl method, 67.43 and 70.43 mg protein/g RSM were hydrolyzed after Protamex and Protease N treatments, respectively. For synergistic effect, two or three effective commercial proteases (Protease M, Protease N and Protease A) were applied to RSM at one time. The highest hydrolysis of RSM protein was observed in both Lowry protein assay (80.3 mg protein/g RSM) and gravimetric methods (153.2 mg protein/g RSM) when three commercial proteases were applied at one time, suggesting the synergistic effect of those proteases.

• Horticultural Science & Technology
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• v.33 no.5
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• pp.687-696
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• 2015

Black mini tomato 'Hei-G' fruits were harvested at different stages of maturity (immature-mature green and mature-black red) and stored at different temperatures (8, 12, and $20^{\circ}C$) to investigate the quality and lycopene content during storage. Weight loss increased dramatically at higher temperature for both harvesting stages without significant differences. Firmness of immature fruits decreased below the initial level of mature fruit (8.1N) after 5, 8, and 19 days storage, when they were stored at 20, 12, and $8^{\circ}C$, respectively. Soluble solid contents of mature fruit increased at initial storage, and were higher as compared to immature fruits before deterioration at each storage temperature. Decrease in titratable acid of mature fruits depended on storage time and temperature. However, titratable acid of immature fruits showed little change during storage, and so it did not affect flavor. Hunter a value changed greatly in immature fruit stored at high temperature. Unlike ripe tomatoes, there was no significant difference in black tomato Hunter b values of immature and mature fruit at initial and 12 days storage. However, immature fruits stored at $8^{\circ}C$ did not reach full maturity and color development and ripening. High storage temperature increased lycopene production while low storage temperature blocked lycopene development. Shelf life of the immature fruits, which was evaluated by elapsed days to conventional mature stage, was 12 and 15 days when they were stored at 20 and $12^{\circ}C$, respectively. The optimum storage temperature to maintain the quality and lycopene content of mature fruits was $12^{\circ}C$. Moreover, the shelf life of mature fruits stored at $20^{\circ}C$ could reach up to 5 days.

• Journal of Nutrition and Health
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• v.52 no.6
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• pp.515-528
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• 2019

Purpose: This study examined the immunological activity and optimized the mixture conditions of Sargassum horneri (S. horneri) extracts in vitro and in vivo models. Methods: S. horneri was extracted using three different methods: hot water extraction (HWE), 50% ethanol extraction (EE), and supercritical fluid extraction (SFE). Splenocyte proliferation and cytokine production (Interleukin-2 and Interferon-γ) were measured using a WST-1 assay and enzyme-linked immunosorbent assay, respectively. The levels of nitric oxide and T cell activation production were measured using a Griess assay and flow cytometry, respectively. The natural killer (NK) cell activity was determined using an EZ-LDH kit. Results: Among the three different types of extracts, HWE showed the highest levels of splenocyte proliferation and cytokine production in vitro. In the animal model, three different types of extracts were administrated for 14 days (once/day) at 50 and 100 mg/kg body weight. HWE and SFE showed a high level of splenocyte proliferation and cytokine production in the with and without mitogen-treated groups, whereas EE administration did not induce the splenocyte activation. When RAW264.7 macrophage cells were treated with different mixtures (HWE with 5, 10, 15, 20% of SFE) to determine the optimal mixture ratio of HWE and SFE, the levels of nitric oxide and cytokine production increased strongly in the HWE with 5% and 10% of SFE containing group. In the animal model, HWE with 5% and 10% of SFE mixture administration increased the levels of splenocyte proliferation, cytokine production, and activated CD4⁺ cell population significantly, with the highest level observed in the HWE with 5% of SFE group. Moreover, the NK cell activity was increased significantly in the HWE with 5% of SFE mixture-treated group compared to the control group. Conclusion: The optimal mixture condition of S. horneri with immune-enhancing activity is the HWE with 5% of SFE mixture. These results confirmed that the extracts of S. horneri and its mixtures are potential candidate materials for immune enhancement.