• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.6
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• pp.754-760
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• 2006

This study was conducted to examine the quality characteristics of canned kimchi prepared by minimal thermal processing. Korean cabbage kimchi was fermented at $20^{\circ}C$ for several days up to acidity $0.5{\pm}0.1%$, was packaged in cylindrical can of 115 mL and pasteurized at low temperature. Thermal processing times based on $F_{60}$ value at geometrical center of the can were determined as 23.1, 17.7 and 12.7 min at 65, 70 and $80^{\circ}C$, respectively. The quality changes of the processed kimchi were measured during storage at $20^{\circ}C$. The pH of pasteurized kimchi was higher than that of unpasteurized control. The number of lactic acid bacteria was reduced to about $10^{2}{\sim}10^{3}$ (CFU/mL). The pasteurized kimchi product showed better texture and color values compared to the control, while resulting in the lower carotenoid and ascorbic acid contents. Kimchi preparation by minimal thermal processing had a positive effect for reduction of sour taste and sour flavor in sensory quality, but gave adverse effect in acceptability because of off-taste and off-flavor.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.6
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• pp.768-773
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• 2006

Effect of gamma irradiation on the microbiological and physicochemical characteristics of vacuum-packaged sugar-treated corns was examined to improve taste and shelf-life during storage at room or low temperature. When the vacuum-packaged sugar-treated corns were stored at $25^{\circ}C$ for 7 months, total counts and yeast and molds in the control increased approximately 2.4 and 3.5 log CFU/g, respectively but complete inactivation was observed for irradiated corns at 3 and 5 kGy. Similar results were observed at $15^{\circ}C\;and\;4^{\circ}C$ storage. There were no significant differences in hardness between irradiated sugar-treated waxy corns and control group before storage, but the hardness in control significantly increased during the storage, compared to those of irradiated corns. Also, changes in sugar content were not significant between the irradiated sugar-treated waxy corns and control during storage. Sensory evaluation for steamed-waxy corns showed that total sensory scores were higher in irradiated corns than in control, which were increased with irradiation doses. It was considered that maintaining good quality and increasing shelf-life of irradiated vacuum-packaged sugar treated corns could be possible at $15^{\circ}C$ storage for long-term period.

• Journal of Korean Society of Forest Science
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• v.95 no.3
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• pp.261-267
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• 2006

A nursery trial comprising 109 progenies of 5 populations of Cornus kousa was analysed using multivariate analysis of 12 quantitative traits (growth and leaf form). The aim of this study was to examine geographic variation of the species based on the single, existing nursery trial to support a genetic resource conservation plan of Cornus kousa in Korea. Nested Anova showed that there were statistically significant differences among populations as well as among families within populations in all 12 quantitative traits. In 10 of 12 traits, variance components among families within populations were higher than those among populations. Cluster analysis using complete linkage method showed three groups to Euclidean distance 0.8. Among principal components, primary 2 principal components appeared to be major variables because of the loading contribution of 91.9%. The first contribution component was maximum width, vein number, blade length/petiole length and upper 1/3 width lower 1/3 width; the second one was height, diameter at root collar, blade length, upper 1/3 width, petiole length and petiole length/vein number, respectively. But all characters showed no significant difference with the pattern of geographic distribution.

• Journal of Korean Society of Forest Science
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• v.95 no.3
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• pp.328-333
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• 2006

This study was conducted to find the characteristics of photosynthesis, leaf and fruit by crown layers in Rubus coreanus Miq. Light compensation points were shown PPFD 33, 20 and $5{\mu}mol\;m^{-2}\;S^{-1}$ at upper, middle and lower layer, respectively. Light saturation points were appeared PPFD 1000, 500 and 200 and their net photosynthesis rate were 8.52, 5.25 and $3.60{\mu}mol\;CO_2\;m^{-2}S^{-1}$ at upper, middle and lower layer, respectively. Uiryeong 7 which was viny type showed higher net photosynthetic rate than others at upper layer. Songgye 6 which was upright type showed lower net photosynthetic rate than others at lower layer. Chlorophyll contents of middle layer had the highest value in the all layers and upper layer showed the lowest value. Most characteristics of leaf morphology were showed that middle and lower layer had higher value than upper layer. That trend was contrary to characteristics of photosynthesis by crown layers. However, dry weight per leaf area and most characteristics of fruit had the highest value at upper layer and that was similar to characteristics of photosynthesis by crown layers. Also, sugar contents of fruit showed the highest value at middle layer.

• Journal of Korean Society of Forest Science
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• v.95 no.3
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• pp.250-255
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• 2006

Pinus densiflora is a dominant conifer species in Korea and also distributed in regions of Japan and eastern China. Success in the establishment and productivity of forest tree plantation is largely determined by selection of species and seed source. The provenance tests of Pinus densiflora in Korea are underway. However, the information of the growth performance of Japanese and Chinese provenances are insufficient. Therefore, this study was conducted to evaluate the growth performance of Pinus densiflora Japanese provenances. Data were collected from a provenance trial including established by Korea Forest Research Institude at Chungju in 1970. Six Japanese provenances ($31^{\circ}90^{\prime}{\sim}40^{\circ} 27^{\prime}$ in latitude and $128^{\circ}47^{\prime}{\sim}141^{\circ}80^{\prime}$ in longitude) were included in this trial. Pyeongchang provenance at Kangwon province in Korea was used for reference provenance. At nursery stage, the height and diameter at root collar of six Japanese provenances were smaller than those of Pyeongchang provenance. Among Japanese provenances, Kasahara provenance showed higher growth performance than those of others. The provenance rankings of growth performance were fluctuated until age 11. However, the growth performance of Japanese provenances showed higher than those of reference provenance after age 17. Kirishima-yama provenance showed best growth performance. Simple correlation analysis was conducted to investigate the geographic factors affecting growth performance. The height growth showed negative corelation with latitude of seed origin. Generally, Japanese provenences of Pinus densiflora were well adapted and grown in Chungju. However, it was suggested that further studies on other sites need to generalize the results of this study.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.6
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• pp.663-669
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• 2007

The solvent extracts of Sargassum muticum, which were extracted by using several solvents with different polarities, were prepared for use as natural preservatives. The S. muticum extract with 80% ethanol was sequentially fractionated with n.hexane, dichloromethane, ethylacetate, and butanol. In order to effectively screen for natural preservatives agents, we first investigated the antioxidant activities such as DPPH radical scavenging capacity, superoxide radical scavenging capacity, and xanthine oxidase inhibitory activity of the S. muticum extracts. Through the screening system, we found that dichloromethane and ethylacetate fraction had high antioxidant activity with increments of the extract concentration. The antimicrobial activities and cell growth inhibition were investigated for each strain with the different concentrations of S. muticum extracts. Antimicrobial activities were shown in ethanol, dichloromethane, and n.hexane fractions of S. muticum. However, butanol, ethylacetate and water fractions showed weak antimicrobial activity against the tested microorganisms. Among the five fractions, dichloromethane fraction showed the highest antimicrobial activities against microorganisms tested, such as Bacillus sublitis, Listeria monocytogenes, Staphylococcus aureus, Escherichia coli, Salmonella Enteritidis and Pseudomonas aeruginosa. The polyphenolic compounds from ethanol, n.hexane, dichloromethane, ethylacetate, butanol, and water fractions were 63.96 mg/g, 8.49 mg/g, 28.11 mg/g, 172.64 mg/g, 114.56 mg/g, and 34.91 mg/g, respectively. The dichloromethane fraction could be suitable for development as a food preservative.

• The Korean Journal of Pesticide Science
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• v.9 no.3
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• pp.205-213
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• 2005

This study was conducted to evaluate the response of the selected aquatic plants to sulfonylurea(SU)-herbicides, which have been used widely in rice-cultivating areas in Korea, and the possibility of using them as bio-indicator species for biodiversity conservation. The aquatic plants identified in Kangwon province where butachlor have been used extensively for many years were much more varied than those in Chonnam where SU-herbicides have been used extensively for many years. The growth responses of Monochoria korsakowii, Marsilea quadrifolia and Salvinia natans to sulfonylurea herbicides such as bensulfuron-methyl(BSM) and pyrazosulfuron-ethyl(PSE), were much more sensitive than those to butachlor and molinate. The $GR_{50}$ values of BSM and PSE for M. korsakowii, M. quadrifolia and S. natans were relatively very low when compared with those of butachlor and molinate. The number of internode and dry weight of M. quadrifolia which was exposed to herbicides runoff from rice fields were seriously affected. The acetolactate synthase(ALS) activities of M. quadrifolia sensitively inhibited by BSM and PSE were, and $I_{50}$(Inhibition 50%) were 5.6 and 2.1 nM, respectively.

• Journal of Life Science
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• v.19 no.1
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• pp.52-57
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• 2009

This study was carried out to investigate the antioxidative and antimicrobial activities of Celastrus orbiculatus (CO). CO was extracted with methanol and then further fractionated with n-hexane (COMH), butanol (COMB), methanol (COMM) or aqueous (COMA) to get active fractions. The antioxidative activity of fractions from CO was investigated by measuring the scavenging activities of CO against DPPH radical, peroxynitrite ($ONOO^-$) and reactive oxygen speicies (ROS). Among the various solvent fractions, the COMB showed a marked scavenging effect against DPPH radical, peroxynitrite ($ONOO^-$) and reactive oxygen species(ROS). The antimicrobial activity was increased in proportion to its concentration by the paper disk method. Among the various solvent fractions, the COMM and COMB fractions of CO showed strong antimicrobial activities. The results suggest that The CO may be suitable for development as a food preservative and alternative antioxidant.

• Korean Journal of Food Science and Technology
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• v.31 no.3
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• pp.625-630
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• 1999

This work was to study drying characteristics of the brown rice koji, an enzymic health food, using microwave under vacuum. Cooked brown rice was inoculated with Aspergillus oryzae and incubated at $32^{\circ}C$ for 6 days. The brown rice koji was dried by different drying methods: microwave vacuum drying, hot air drying, vacuum drying and freeze drying. Each drier except freeze drier was set to maintain the sample temperature at $40^{\circ}C$. During microwave vacuum drying, the sample reached $40^{\circ}C$ much faster (within $5{\sim}10\;min$) and was dried much faster (2 hrs) than the other drying methods. The initial drying rate of microwave vacuum drying was ten times faster than that of hot air drying. The microwave vacuum drying produced a dry sample of the highly retained enzymic activity, followed by freeze drying, vacuum drying, and hot air drying.

• Korean Journal of Food Science and Technology
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• v.36 no.6
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• pp.995-1000
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• 2004

Nutritional composition and antioxidative capacity of mulberry fruit (Ficus-4x) were investigated for evaluation as new red-colored fruit. Contents of moisture, crude fat, crude protein, and vitamin C were similar, whereas that of crude ash was higher, to those of other berry fruits. Contents of minerals (Ca, 14.33 mg/100 g; P, 39.98 mg/100 g; Fe, 6.01 mg/100 g; Zn, 4.04 mg/100 g; Mn, 2.26 mg/100 g), particularly Fe, were higher than those of other berry fruits. Hardness, springness, cohesiveness, gumminess, and chewiness of mulberry fruit were higher, and color values (L, 36.03; a, 1.80; b, 1.54) were lower than those of strawberry. Relative scavenging activities of mulberry fruit methanol extract and its cyanidine 3-glucoside on 1, 1-diphenyl-2-picrylhydrazy radical (DPPH) were 35.7 and 78.2%, respectively, using butylated hydroxyanisole (BHA) as standard. Antioxidant activities in corn oil (peroxide values and conjugated dienoic acid) were tertiary butylhydroquinone (TBHQ) > mulberry fruit ethanol extract > mulberry fruit water extract > butylated hydroxytoluene (BHT) > tocopherol. Results show mulberry fruit can be very useful red-colored fruit for development of functional foods with beneficial effects on radical scavenging and antioxidative capacities.