• Journal of Korean Society of Forest Science
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• v.87 no.1
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• pp.106-112
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• 1998

This study was conducted to figure out the relationships among soil chemical properties and bacterial biomass related to denitrification and sulfur-reducing and the activity of dehydrogenase, and ultimately to consider the usefulness of dehydrogenase activity as a tool for evaluating the dynamics of forest soil ecosystem. Four sites were selected for the collection of soil samples within two regions(Onsan industrial estate as a polluted region and Mt. Mani at Kanghwa island as a clean area) with two forest types (coniferous and deciduous stands). The soils of Mt. Mani showed higher amount of organic matter, total nitrogen and available phosphorus than those collected from Onsan industrial estate, which indicated that the soils were more beneficial for microbial growth than those of Onsan. The dehydrogenase activity was more sensitive than the denitrifying bacteria or sulfur-reducing bacteria since the activity was significantly different between the regions and season while the two bacterial biomass were not significantly different between the two regions. In addition, the dehydrogenase activity showed relatively high correlation coefficients with organic matter(r=0.53, p=0.004), total nitrogen(r=0.41, p=0.008) and C/Ava. P-ratio(r=-0.52, p=0.001), which was thought to be closely related with microbial activity. Thus, the dehydrogenase activity was thought to be a useful index of soil ecosystem dynamics with considering that the technique need to be applied with the same soil texture for the comparison of the activity as other researchers indicated.

• Journal of the Korean Wood Science and Technology
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• v.34 no.2
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• pp.88-94
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• 2006

The purpose of this study is to examine the relationship between antioxidant activities and chemical structures of various chalcones. Twenty-two chalcones were assessed for their radical scavenging activity using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. Of 22 compounds tested, the most active on DPPH radical was 2',4-dihydroxy-3,3'5-trimethoxy-5'-propylchacone (4) (72.6% at 100 ppm). It was followed by 3',4'-dihydroxy-3,4,5-trimethoxy-6'-methylchalcone (6), 2',4,4'-trihydroxy-3-methoxy-5-propenylchalcone (7) and 2',4,4'-trihydroxy-3,5-dimethoxychalcone (13). Based on the results, we concluded that the scavenging activity is controlled by the number and the position of the substitution in the compound.

• Korean Journal of Plant Resources
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• v.32 no.6
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• pp.698-704
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• 2019

Quercus mongolica (QM), which belongs to fagaceae, is one of the oak native to Korea. We evaluated the anti-inflammatory effect of branches extracted with 70% ethanol of QM (QM-B) and elucidated the potential signaling pathway in LPS-induced RAW264.7 cells. The QM-B showed anti-inflammatory activity through inhibition of NO production. The QM-B dose-dependently suppressed NO production by inhibiting iNOS, COX-2 and IL-6 expression in LPS-induced RAW264.7 cells. The QM-B inhibited the degradation and phosphorylation of IκB-α and NF-κB activation. The QM-B suppressed the phosphorylation of p38 and ERK1/2. Also, the QM-B increased HO-1 expression. These results suggested that QM-B may utilize anti-inflammatory activity by suppressing NF-κB and MAPK signaling pathway and inducing HO-1 expression indicated that the QM-B can be used as a natural anti-inflammatory drugs.

• Journal of the Korean Wood Science and Technology
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• v.47 no.4
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• pp.498-508
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• 2019

This study was carried out to investigate the potential of Korean red pine (Pinus densiflora) inner bark extracts as an antidiabetic agent. The ethyl acetate soluble fraction of the bark extracts was chromatographed on a Sephadex LH-20 column to yield five compounds, which structures were elucidated by NMR spectroscopy. The isolated compounds were (+)-catehin, (-)-epicatechin, taxifolin, taxifolin-3'-O-${\beta}$-D-(+)-glucose and $\tilde{n}$-courmaric acid. The antidiabetic activity of the different fractions, including the crude extracts and isolated compounds, was evaluated by ${\beta}$-cells insulin secretion and glucose uptake in skeletal muscle cells. The insulin secretion was 128% for taxifolin at $25{\mu}g/mL$. However, the other samples had no effect on this test. For the glucose uptake activity assay, $1{\mu}M$ insulin and 2 mM metformin were used as controls. Both the crude extract and taxifolin showed relatively low activity values, but the other samples yielded glucose uptake values over 260%. ${\rho}$-courmaric acid showed the highest uptake (270%). The results confirmed that Korean red pine extracts may be used as a hypoglycemic agent.

• Korean journal of applied entomology
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• v.48 no.1
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• pp.53-57
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• 2009

Biological Characteristics of Lycorma delicatula and insecticidal activity of some insecticides against nymphs of L. delicatula was investigated. Nymph of L. delicatula had 4 instars, and color of body was black. There were white spots on the body of 1st-3rd nymph. Upper body became red at 4th nymph. Adult forewings were brownish, and had black spots. Color of hind wing were red. The egg mass was covered with a yellowish brown secretion. The adult of L. delicatula emerged once a year. Among test insecticides, deltamethrin 1% EC and fenitrothion 50% EC showed very quick and strong insecticidal activity against the 2nd-3rd nymphs of L. delicatula. Imidacloprid 4% SL and clothianidin 8% SC showed 100% insecticidal activity at 24h after treatment. Thiacoprid 10% SC revealed the weakest insecticidal activity among the insecticides tested.

• Proceedings of the Korean Society of Applied Entomolohy Conference
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• 2001.05a
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• pp.73-73
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• 2001

• Mycobiology
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• v.36 no.1
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• pp.74-76
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• 2008

To obtain basic information on the biochemical property of basidiospores of shiitake mushroom (Lentinula edodes), the ability of producing extracellular enzyme was assessed using a chromogenic plate-based assay. For the aim, amylase, avicelase, $\beta$-glucosidase, CM-cellulase, pectinase, proteinase, and xylanase were tested against monokaryotic strains generated from forty basidiospores of two different parental dikaryotic strains of shiitake mushroom, Sanjo-101Ho and Sanjo-108Ho. These two parental strains showed different degree of extracellular enzyme activity. No identical patterns of the degree of enzyme activity were observed between monokaryotic strains and parental strains of the two shiitake cultivars. The degree of extracellular enzyme activity also varied among monokaryotic strains of the two shiitake cultivars. Our results showed that dikaryotic parental strains of shiitake mushroom produce monokaryotic basidiospores having very diverse biochemical properties.

• Journal of Naturopathy
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• v.10 no.1
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• pp.33-41
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• 2021

Purposes: We studied whether forest bathing is effective in improving the stress of the human body. Therefore, we investigated changes in pulse rate, stress index, and autonomic nervous system after 2 hours of forest bathing on Jeju Samdasu Forest Methods : The study was conducted before and after forest bathing through heart rate variability and questionnaire. Results: After forest bathing, the average pulse rate of the experimental group was significantly increased. The stress index significantly decreased in the post-test in the experimental group. The cumulative stress, sympathetic activity (LF), parasympathetic activity (HF) change, and LF/HF ratio were slightly different from those of post-test in the experimental group, but were not statistically significant. In the survey of job stress average index and state characteristic anxiety index through questionnaire, it decreased significantly after forest bathing (p<.001). Conclusions: The Samdasu forest bathing has been proven effective in enhancing pulse and reducing stress, so it is evaluated that forest bathing is effective in promoting health.

• Korean Journal of Pharmacognosy
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• v.44 no.3
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• pp.242-252
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• 2013

This study was evaluated to biological activity of breeding lines from Acantopanax( A. sessiliflorus: ASF, A. koreanum: AKN, A. chiicanensis: ACS, A. senticosus: AST) and parts(root, stem, fruit, and leaf) and various extracted solvents( 100% water, 100% EtOH, 50% EtOH). Total polyphenol content of AKN root in 100% water extracts was high detected 464.46 mg/100 g. Total flavonoid content in the leaf was significantly higher than in other parts. The content of total sugars was high in the 50% EtOH extracts and fruit. The major free amino acids were arginine in all extracts. The content of arginine was detected in the root of AKN(1.807 mg/100 mg). Contents of eleutheroside B, E were high detected in 100% water extracts. Antioxidative capacity in the leaves of AKN was the higher than other extracts($EC_{50}=84.8{\mu}g/mL$). The results would be useful for understanding of the physiological properties of AKN extracts.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2023.04a
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• pp.43-43
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• 2023

In this study, we investigated in vitro inhibitory activity of wild-simulated ginseng (WSG) against non-alcoholic fatty liver disease using HepG-2 cells. T0901317 treatment increased the lipid accumulation in HepG-2 cells, but WSG treatment inhibited T0901317-mediated lipid accumulation. In addition, WSG downregulated T0901317-mediated expression of SREBP-1c, ACC, FAS and SCD-1 protein. In addition, WSG increased the phosphorylation level of LKB1 and AMPK. Compound C treatment blocked WSG-mediated downregulation of SREBP-1c protein. In conclusion, WSG is considered to inhibit the accumulation of lipids and triglycerides in HepG-2 cells by inducing the activation of LKB1 and AMPK successively, thereby reducing the expression of FAS, ACC, and SCD-1 through suppression of SREBP-1c expression.