• Journal of Life Science
• /
• v.18 no.1
• /
• pp.103-108
• /
• 2008

An agar-degrading marine bacterium, strain AS-1 was isolated from the seawater. The strain AS-1 was identified as Sphingomonas paucimobilis (90% probability) by VITEK. The optimum medium for agarase activity of the isolated strain was determined to be marine medium, marine broth 2216 containing 0.1% agar as carbon source. An extracellular agarase was purified 104-fold from the culture supernatant by ammonium sulfate precipitation, ion exchange chromatography and gel filtration methods. The molecular weight of the purified enzyme was estimated to be 80 kDa by SDS-PAGE. The optimum pH and temperature for activity were 7.0 and $40^{\circ}C$, respectively. Antioxidative activity of the strain AS- was 72% in the supernatant cultured for 12 h. The culture supernatant of the strain AS-1 showed antibacterial activity against bacteria causing putrefaction and food poisoning such as Escherichia coli, Staphylococcus aureus and Proteus vulgaris. However, the cell growth of the lactic aicd forming strain, Lactobacillus plantarium was promoted by the treatment of 10% culture supernatant of an agar-degrading strain.

• Journal of Life Science
• /
• v.17 no.1 s.81
• /
• pp.105-109
• /
• 2007

This study was carried out to investigate the biological effects oak wood vinegar. Antimicrobial activity was tested in five microbial species at the concentration of 5 to $50{\mu}l$ of oak wood vinegar by paper disc method. Growth of P. oleovoranse, P. vulgaris, E. coli, S. aureus and Prevotella intermedia was inhibited at a dose of as low as $50{\mu}l$ of oak wood vinegar. Antioxidant activities were measured by using DPPH radical scavenging and SOD-like activity. DPPH radical scavenging and SOD-like activities were 90% and 65% at the concentration of $25{\mu}l\;and\;50{\mu}l$ of oak wood vinegar, respectively. Stimulation of the macrophages RAW264.7 cells with lipopolysaccharide (LPS) resulted in increased production of nitric oxide (NO) in the medium. However, the oak wood vinegar showed marked inhibition of NO synthesis in a dose-dependent manner. This result suggest that oak wood vinegar plays significant role for activation of immune system in the pathogenesis of inflammatory diseases.

• Food Science of Animal Resources
• /
• v.32 no.1
• /
• pp.13-17
• /
• 2012

Two experiments were conducted to investigate the dietary effect of chlorella vulgaris on egg production and lutein incorporation into chicken eggs. In Exp. 1, a total of three hundred, 70 wk-old Hy-Line brown layers were divided into six groups with five replicates and fed each experimental diet (corn-SBM based control diet and diets with 0.1, 0.3 or 0.5% chlorella powder and with 0.8 or 2.4% chlorella cultured media) for 6 wk, respectively. The egg production in the groups fed diets containing the chlorella powder and chlorella cultured media were higher than that of the control group (p<0.001). As dietary chlorella levels increased, the yolk color linearly increased. However, there were no significant differences in egg-shell qualities. The layers fed diet with 2.4% chlorella cultured media showed the highest Haugh unit value. In Exp. 2, a total of one hundred-eight 80 wk-old Hy-Line brown layers were assigned into four groups with three replicates per group (9 birds per replicate). The birds were fed one of four experimental diets (0, 0.5, 1.0 or 2.0% chlorella powder) for 4 wk, followed by a 14 d feeding of a withdrawal diet devoid of chlorella powder. At 2 wk, the lutein greatly increased with increasing levels of chlorella powder in birds fed diets containing more than 1%. The maximum incorporation of lutein into eggs was reached after 2 or 3 wk of feeding diets with chlorella powder. After a 7 d withdrawal, the lutein contents of egg yolks in the groups fed diets with more than 1% chlorella powder were still higher than that of control group (p<0.05). No significant differences in the lutein levels were found among groups after a 14 d withdrawal period. These results indicated that the use of chlorella in layer diets was effective in improving egg production and egg quality and for the production of lutein fortified eggs.

• The Korean Journal of Pesticide Science
• /
• v.18 no.3
• /
• pp.175-180
• /
• 2014

This study was carried out to determine the economic injury level and economic threshold level on beet (Beta vulgaris L.) infested with Spoladea recurvalis in the plastic greenhouse condition in 2010. The second instar larvae of S. recurvalis were inoculated with 7 different density levels on the each 10 beet plants as a replication. Injury levels of beet leaves and density of S. recurvalis were increased with the inoculation density of S. recurvalis. However, yield and marketable commodity of beet were decreased. Linear relationship between the percent yield reduction (Y) of beet leaves and different infestation densities of S. recurvalis (X) was estimated by the following equation Y = 1.226x + 3.36. Based on the relationships between the densities of S. recurvalis larvae and yield index of beet leaves, the number of second instar larvae which caused 5% loss of yield, economic threshold level was estimated as 1.1 larvae/10 plants for the planting 10 days. The percent yield reduction (Y) of beet roots infested with different densities of S. recurvalis (X) estimated by the following equation Y = 1.537x + 1.4634 after inoculation for 10 days at 3rd harvesting of leaves. Based on the relationships between the densities of S. recurvalis larvae and yield index of beet roots, the number of second instar larvae which caused 5% loss of yield, economic threshold level was estimated as 6.4 larvae/10 plants for the planting 10 days.

• Food Science and Preservation
• /
• v.16 no.1
• /
• pp.1-7
• /
• 2009

Watermelons (Citrulus vulgaris Schrad) are usually sorted manually by weight, appearance, and acoustic impulse, so grading of maturity and internal quality is subject to inaccuracies. It was necessary to develop a nondestructive evaluation technique of internal watermelon quality to reduce human error. Thus, acoustic characteristics related to internal quality factors were analyzed. Among these factors, three (ripeness, presence of an internal cavity, and blood-colored flesh) were selected for evaluation. The number of peaks and the sum of peak amplitudes for watermelons with blood-colored flesh were lower than for normal fruits. The portable evaluation system has an impact mechanism, a microphone sensor, a signal processing board, an LCD panel, and a battery. A performance test was conducted in the field. The internal quality evaluation model showed 87% prediction accuracy. Validation was conducted on 72 samples. The accuracy of quality evaluation was 83%. The quality of samples was evaluated by an inspector using conventional methods (hitting the watermelon and listening to the sounds), and then compared with prototype results. The quality evaluation accuracy of the prototype was better than that of the inspector. This nondestructive quality evaluation system could be useful in the field, warehouse, and supermarket

• Korean Journal of Environment and Ecology
• /
• v.23 no.4
• /
• pp.285-293
• /
• 2009

This research had been executed to find out the structure of Magnolia obovata community, a dispersal range and characteristics of scatter investigation, and to prepare management measure of it. In the result of this study, Magnolia obovata was distributed in a native plant community from planting trees of UNESCO Peace Center. The maximum numbers of Magnolia obovata were found in $20{\sim}100m$ from trees of mother. Seed of Magnolia obovata has a characteristics of gravity dispersal. But some individuals was found in 420m from its tree of mother. Seeds of Magnolia obovata has a characteristics of animal dispersal, too. Major species of animal dispersal are Garrulus glandarius, Ciurus vulgaris coreae, and Tamias sibiricus asiaticus in the study site. The importance value between native plants and Magnolia obovata had a negative relation. Because Magnolia obovata is more shade tolerant than other trees. Also, the growth of Magnolia obovata is faster than other trees. And so if the influence of Magnolia obovata reduce, it is necessary to expand native plant community, and to cut Magnolia obovata over 10m of the height and over 10cm of the DBH, for preventing influence of Magnolia obovata.

• Korean Journal of Environment and Ecology
• /
• v.27 no.1
• /
• pp.22-29
• /
• 2013

This research was carried out for revealing the co-relationships between insect-pollinators and the plant species of Labiatae and Umbelliferae, insects visiting in flower and the flowers in Korea, were studied from April 2010 to August 2012. The sum of flower visiting degrees in Labiatae are shown 21 in Hymenoptera, 16 in Lepidoptera, and the lowest 1 in Diptera and Coleoptera, respectively. The sum of flower visiting degrees in Umbelliferae are shown 27 in Diptera, 24 in Hymenoptera, 21 in Coleoptera, and 13 in Lepidoptera, respectively. 17 pollinator species visited the flower of Angelica gigas, next 15 pollinator species did the flower of Agastache rugosa, 13 pollinator species did the flower of Prunella vulgaris var. lilacina. 13 pollinator species foraged on the flower of Peucedanum terebinthaceum. and then 11 pollinator species on the flower of Angelica dahurica. Only 1 pollinator species visited the flower of Clinopodium chinense var. grandiflora and Isodon excisus. Pollinators of Coleoptera and Diptera visit more frequently to the flowers of Umbelliferae than those of Labiatae. Pollinators of Lepidoptera and Diptera visit more frequently white flower than purple one. This study found out that mutualistic relations between plants and insect pollinators in Korea.

• Journal of Life Science
• /
• v.26 no.8
• /
• pp.970-975
• /
• 2016

Acne vulgaris is a common chronic skin disorder that affects millions of people. The pathogenesis of acne has been known to be closely associated with the bacterium Propionibacterium acnes. Here we investigated the anti-acne activity of Lactobacillus plantarum K-1 BR by observing the expressions of proinflammatory cytokines, TNF-α, IFN-γ and IL-8, of human keratinocytes. When we applied heat-killed P. acnes to HaCaT cells, the inflammatory cytokines were induced by two- to four-fold compared to the normal control. When the bacteriocin, purified from L. plantarum K-1 BR, was pretreated to the HaCaT cells, the expression levels of TNF-α and IFN-γ stimulated by P. acnes significantly decreased to 25% and 30% of the induced levels, respectively. The IL-8 levels also significantly decreased with the concentration dependent manner of the bacteriocin. These results suggest that the bacteriocin from L. plantarum K-1 BR could reduce the expression levels of inflammatory cytokines and thus may relieve inflammations caused by acne.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.39 no.10
• /
• pp.1433-1438
• /
• 2010

This study was carried out to investigate the antioxidative and antimicrobial activities of internal organs of Aplysia kurodai (AK). The internal organs of AK were extracted with methanol (AKM), which was then further fractionated into four subfractions by using solvent partition method, affording hexane (AKMH), methanol (AKMM), butanol (AKMB), and aqueous (AKMA) soluble fractions. The antioxidative activity of fractions from AK was investigated by measuring the scavenging activities of AK against DPPH radical, peroxynitrite ($ONOO^-$) and reactive oxygen species (ROS). Among the various solvent fractions, AKMB 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, AKMM fractions of AK showed the strongest antimicrobial activities. The methanol extracts exhibited antimicrobial activity against all organisms tested, while the hexane extracts showed antimicrobial activity only against Proteus vulgaris. The results suggest that the AK may be suitable for development as a food preservative and alternative antioxidant.

• Journal of Bio-Environment Control
• /
• v.19 no.3
• /
• pp.130-134
• /
• 2010

To investigate effects of deep tillage before planting on physicochemical properties of soil, growth and fruit characteristics in cultivation of watermelon (Citrullus vulgaris L. cv. 'Uriggul') under plastic film house, this study was conducted in cultivating field of Gochang Junbuk. pH in soil after harvest compared with soil before planting of watermelon had almost no change, but EC lowed greatly in the two treatments. Available phosphate concentration in the soil with the deep tillage treatment was lower, K concentration of exchangeable cation decreased greatly than these with conventional tillage treatment. In the growth at 27th day after planting plant, stem length to 10th node from the first node, leaf width with deep tillage treatment were longer, bearing node of the first and second flower and wilting degree were lower than these with conventional tillage treatment. In the growth of harvesting time, the stem length to 30th node from the first node with the deep tillage treatment were longer, leaf discoloration degree was lower than these with conventional tillage treatment. Also, the harvested fruits length, diameter, peel hardness, and weight were significantly better than these with conventional tillage treatment.