• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.1
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• pp.107-111
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• 2020

In this study, we examined the maturation and spawning of yellowback seabream Dentex tumifrons using samples collected by monthly bottom trawling in Korean coastal waters from January to December 2018. We analyzed monthly changes in gonadosomatic index (GSI), maturity stage, histology, fecundity, and total length at group maturity. Spawning occurred in May and October. Fecundity varied with total length as F=1.3754TL^3.2664, with a range of 1,220 to 155,625 eggs per female. At group maturity, 50%, 75%, and 97.5% estimates of female total length were 18.4, 20.5, and 25.3 cm, respectively.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.1
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• pp.67-73
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• 2020

The maturity and spawning of the yellow goosefish Lophius litulon were studied using samples collected monthly from January to December 2018 from the coastal waters of Korea. We analyzed monthly changes in maturity stage, gonadosomatic index (GSI), total length (TL) at 50%, 75%, and 97.5% group maturity, egg diameter and fecundity. The spawning period was from January to June. The size of eggs spawned was between 0.30 to 1.28 mm. Fecundity varied between 328,314 to 1,624,783 eggs. The percentage of sexually mature females estimated from a logistic function was over 50% at 48.67 cm TL, 75% at 56.76 cm TL and 97.5% at 74.89 cm TL.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.1
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• pp.43-49
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• 2020

The maturation and spawning of red seabream Pagrus major were investigated using 1,014 samples collected monthly from January to December of 2018, in the South Sea of Korea. Based on monthly changes in maturity stage and gonadosomatic index, the spawning period was estimated to be between April and August, with peak spawning occuring from May to June. Fecundity varied between 228,996 and 4,544,948 eggs. The relationship between fecundity (F) and fork length (FL) in this species can be expressed by the equation F=0.4869FL^3.9452 (R²=0.7448). Using a logistic function, the percentage of sexually mature females was estimated to be over 50% for fish with a FL of 35.3 cm.

• Journal of Microbiology and Biotechnology
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• v.26 no.8
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• pp.1392-1397
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• 2016

Curcumin is a polyphenol derived from the plant Curcuma longa, which is used for the treatment of diseases associated with oxidative stress and inflammation. The present study was undertaken to determine the protective effect of curcumin against naproxen-induced gastric antral ulcerations in rats. Different doses (10, 50, and 100 mg/kg) of curcumin or vehicle (curcumin, 0 mg/kg) were pretreated for 3 days by oral gavage, and then gastric mucosal lesions were caused by 80 mg/kg naproxen applied for 3 days. Curcumin significantly inhibited the naproxen-induced gastric antral ulcer area and lipid peroxidation in a dose-dependent manner. In addition, curcumin markedly increased activities of radical scavenging enzymes, such as superoxide dismutase (SOD), catalase, and glutathione peroxidase in a dose-dependent manner. Specifically, 100 mg/kg curcumin completely protected the gastric mucosa against the loss in the enzyme, resulting in a drastic increase of activities of radical scavenging enzymes up to more than the level of untreated normal rats. Histological examination obviously showed that curcumin prevents naproxen-induced gastric antral ulceration as a result of direct protection of the gastric mucosa. These results suggest that curcumin blocks naproxen-induced gastric antral ulcerations through prevention of lipid peroxidation and activation of radical scavenging enzymes, and it may offer a potential remedy of gastric antral ulcerations.

• Korean Journal of Environmental Agriculture
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• v.34 no.3
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• pp.244-251
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• 2015

BACKGROUND: Recent studies have described the importance of bacteria that can degrade polycyclic aromatic hydrocarbons (PAHs). Here we screened bacterial isolates from commercial gasoline for PAH degraders and characterized their ability to degrade PAHs, lipids and proteins as well as their enantioselective epoxide hydrolase activity, salt tolerance, and seawater survival. METHODS AND RESULTS: One hundred two bacteria isolates from commercial gasoline were screened for PAH degraders by adding selected PAHs on to the surface of agar plates by the sublimation method. A clear zone was found only around the colonies of PAH degraders, which accounted for 13 isolates. These were identified as belonging to Bacillus sp., Brevibacterium sp., Micrococcus sp., Corynebacterium sp., Arthrobacter sp., and Gordonia sp. based on 16S rRNA sequences. Six isolates belonging to Corynebacterium sp., 3 of Micrococcus sp., Arthrobacter sp. S49, and Gordonia sp. H37 were lipid degraders. Arthrobacter sp. S49 was the only isolate showing high proteolytic activity. Among the PAH-degrading bacteria, Arthrobacter sp. S49, Brevibacterium sp. S47, Corynebacterium sp. SK20, and Gordonia sp. H37 showed enantioselective epoxide hydrolase activity with biocatalytic resolution of racemic styrene oxide. Among these, highest enantioselective hydrolysis activity was seen in Gordonia sp. H37. An intrinsic resistance to kanamycin was observed in most of the isolates and Corynebacterium sp. SK20 showed resistance to additional antibiotics such as tetracycline, ampicillin, and penicillin. CONCLUSION: Of the 13 PAH-degraders isolated from commercial gasoline, Arthrobacter sp. S49 showed the highest lipid and protein degrading activity along with high active epoxide hydrolase activity, which was the highest in Gordonia sp. H37. Our results suggest that bacteria from commercial gasoline may have the potential to degrade PAHs, lipids, and proteins, and may possess enantioselective epoxide hydrolase activity, high salt tolerance, and growth potential in seawater.

• Korean Journal of Agricultural Science
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• v.45 no.4
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• pp.839-845
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• 2018

As a solution to the rural shortage of labor, mechanization crop production is necessary, but in some cases, the mechanization can cause problems such as a decrease in products due to the expansion of the necessary moderate workspace. The purpose of this study was to compare the yields of pepper by the planting-density for the mechanization of pepper cultivation. Experiments were done with three planting-density levels of $900{\times}300mm^2$(A-T), $1200{\times}450mm^2$(B-T), and $1500{\times}600mm^2$(C-T). In the analysis of growth, the highest values in plant height and thickness and the number of branches were observed with the B-T. C-T showed the highest values in the number of green-pepper and red-pepper and weight of the green-pepper and red-pepper, followed by B-T and A-T. In the analysis of growth, it was concluded that the proportion of the pepper body to the total length increased as the planting-density decreased. C-T had the biggest maximum diameter of the body, followed by B-T and A-T. On the other hand, A-T had the biggest minimum diameter of the body, followed by B-T and C-T. It was judged that the larger the planting-density was, the shorter the length was and the thicker the form was. As a result of measuring the chromaticity, there was no significant statistical difference in quality. Based on the experiment results, the ranking in total yields was in the order of C-T, B-T, and A-T. The reduced planting-density seemed to increase the productivity, while the labor intensity and time were reduced due to the improvement of the working environment.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.57 no.2
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• pp.117-126
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• 2021

Diet composition and trophic level of Trachurus japonicus were studied using 417 specimens collected by trawls, set nets and purse seine fisheries from March 2019 to February 2020 in the South Sea of Korea. The size of T. Japonicus ranged from 7.0 to 49.8 cm in total length. T. japonicus were a carnivore that fed mainly on euphausiids and pisces. In eddition, T. japonicus fed on small quantities of cephalopods, crabs etc. T. japonicus showed ontogenetic changes in feeding habits. The proportion of euphausiids decreased inversely proportional to body size whereas the consumption of pisces gradually increased. As body size of T. japonicus increased the mean number of prey per stomach and the mean weight of prey per stomach tended to increase, but the mean number of prey per stomach was not significantly different. As a result of the feeding strategy analysis, T. japonicus were specialized feeders with pisces and euphausiids as their dominant prey. The trophic level ranged between 3.57 ± 0.54 and 3.91 ± 0.65, and increased asymptotically with size of specimens. The average trophic level of the T. japonicus was 3.79 ± 0.61.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.1
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• pp.73-79
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• 2021

The feeding habits of Chub mackerel Scomber japonicus were investigated using 329 specimens collected from coastal waters of the South Sea of Korea. S. japonicus is mainly a piscivore, consuming small fish such as Engraulis japonicus (%RI: 81.0 %). The diet of Chub mackerel also includes small quantities of thaliaceans, euphausiids, and amphipods. We calculated the trophic level as 3.92 for S. japonicus. The dietary composition of S. japonicus did not show significant differences with size, but differed with season. As the body size of S. japonicus increased, the mean weight of prey within the stomach (mW/ST) increased (One-way ANOVA, P<0.05).

• The Journal of the Convergence on Culture Technology
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• v.9 no.1
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• pp.627-633
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• 2023

This study sought to identify the effects of entrepreneurship orientation and self efficacy on entrepreneurial intentions among workers in the bio-healthcare industry in Korea. As interest in health increases in the age of aging, the bio-healthcare industry is attracting a lot of attention for start-ups as an industry that can create high added value, but there are also aspects that take a relatively long time to develop technology, require a lot of money, and have a relatively high probability of failure. In this study, we measured the level of entrepreneurship orientation and self efficacy of bio-healthcare industry workers and identified the degree of influence on entrepreneurial intentions. Studies have shown that innovativeness, progressiveness, and risk-taking among entrepreneurship orientations all have a significant impact on entrepreneurial intention. In addition, self efficacy has been shown to have a mediating effect on the relationship between innovativeness, progressiveness, risk-taking and entrepreneurial intention.

• Journal of Ginseng Research
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• v.48 no.3
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• pp.323-332
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• 2024

Background: Studies have reported that the combination of two or more therapeutic compounds at certain ratios has more noticeable pharmaceutical properties than single compounds and requires reduced dosage of each agent. Red ginseng and velvet antler have been extensively used in boosting immunity and physical strength and preventing diseases. Thus, this study was conducted to elucidate the skin-protective potentials of red ginseng extract (RGE) and velvet antler extract (VAE) alone or in combination on ultraviolet (UVB)-irradiated human keratinocytes and SKH-1 hairless mice. Methods: HaCaT cells were preincubated with RGE/VAE alone or in combination for 2 h before UVB (30 mJ/cm²) irradiation. SKH-1 mice were orally given RGE/VAE alone or in combination for 15 days before exposure to single dose of UVB (600 mJ/cm²). Treated cells and treated skin tissues were collected and subjected to subsequent experiments. Results: RGE/VAE pretreatment alone or in combination significantly prevented UVB-induced cell death, apoptosis, reactive oxygen species production, and DNA damage in keratinocytes and SKH-1 mouse skins by downregulating mitogen-activated protein kinases/activator protein 1/nuclear factor kappa B and caspase signaling pathways. These extracts also strengthened the antioxidant defense systems and skin barriers in UVB-irradiated HaCaT cells and SKH-1 mouse skins. Furthermore, RGE/VAE co-administration appeared to be more effective in preventing UVB-caused skin injury than these extracts used alone. Conclusion: Overall, these findings suggest that the consumption of RGE/VAE, especially in combination, offers a protective ability against UVB-caused skin injury by preventing inflammation and apoptosis and enhancing antioxidant capacity.