• Journal of the Korean Wood Science and Technology
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• v.47 no.5
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• pp.587-596
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• 2019

This study aimed to determine the antimalarial effect of the Strychnos ligustrina (SLW) wood extracts and to analyze its phytochemicals. The SLW powder samples were macerated with 100% ethanol (E100), 75% ethanol (E75), 50% ethanol (E50), 25% ethanol (E25), and aqueous (A100). The extracts were analyzed by LCMS/MS, and its in-vitro antimalarial activity was tested with Plasmodium falciparum. The results showed that the extract yields of E100, E75, E50, E25, and A100 were 4.3, 5.2, 5.3, 4.7, and 3.6%, respectively. The antimalarial activities of the A100, E25, E50, and E75 extracts were classified as active with $IC_{50}$ values of 38.6, 42.6, 42.9, and $43.7{\mu}g/mL$, respectively. But, the antimalarial activity of the E100 extract was classified as slightly active with $IC_{50}$ values of $87.4{\mu}g/mL$. The dominant compounds contained in the extracts of A100, E25, E50, E75, and E100 was the alkaloid compound, namely brucine with relative concentrations of 24.96, 24.55, 21.33, 11.79, and 11.62%, respectively.

• The Korean Journal of Mycology
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• v.40 no.4
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• pp.191-203
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• 2012

Mycelial growth of ectomycorrhizal fungi (27 strains of 8 species) collected from Korean forests was observed on various culture conditions (media, temperature, pHs). After 60 days of incubation, all strains grown on potato dextrose agar (PDA) and modified Melin-Norkran's agar (MMNA), whereas no mycelial growth was observed on malt extract agar (MEA) or sabouraud dextrose agar (SDA) in some strains including Tricholoma matsutake. Mycelial growth on PDA was poor at high temperature ($30^{\circ}C$) than the low temperature ($10^{\circ}C$). The optimal temperature on PDA and pH in potato dextrose broth (PDB) for mycelial growth in most strains were $20-25^{\circ}C$ and pH 4-5, respectively. All strains tested showed the carboxymethyl cellulase (CM-cellulase) activity and the maximal cellullase activity was expressed by the mycelium of T. matsutake (KFRI 1266) on the CMC agar plate with pH 5.0.

• Korean Journal of Plant Resources
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• v.31 no.3
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• pp.218-227
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• 2018

In this study, we investigated the effect of the extracts from Vaccinium oldhamii on cell proliferation and the regulatory mechanisms of cyclin D1 protein level in human cancer cells. The branch extracts from Vaccinium oldhamii (VOB) showed higher inhibitor effect against the cell growth than leave extracts (VOL) and fruit extracts (VOF) in human colorectal cancer, breast cancer, prostate cancer, non-small lung cancer, pancreatic cancer and liver cancer cells. In addition, VOB decreased cyclin D1 level at both protein and mRNA level. MG132 treatment attenuated VOB-mediated cyclin D1 downregulation. A point mutation of threonine-286 to alanine attenuated cyclin D1 degradation by VOB. In addition, the inhibition of nuclear export by leptomycin B (LMB) attenuated cyclin D1 degradation by VOB. But, the treatment of PD98059 (ERK1/2 inhibitor), SB203580 (p38 inhibitor), SP600125 (JNK inhibitor), LiCl ($GSK3{\beta}$ inhibitor), LY294002 (PI3K inhibitor) or BAY 11-7082 ($I{\kappa}K$ inhibitor) did not affect VOB-induced cyclin D1 degradation. In conclusion, VOB induced cyclin D1 degradation through redistribution of cyclin D1 from the nucleus to cytoplasm via T286 phosphorylation of cyclin D1, which resulted in the inhibition of cancer cell proliferation.

• Journal of the Korean Society of Industry Convergence
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• v.23 no.4_2
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• pp.593-601
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• 2020

This study was conducted to analyze the physical strain with heart rate monitor in timber harvesting operations in order to reduce occupational accidents. The timber harvesting activities are manual cutting(felling, limbing and bucking) with a chainsaw and extraction by cable yarder. The study took place on Japanese larch stand. The average height was 26m and average diameter at breast height(DBH) was 3 7cm. The havest unit was gentle slope to steep slope. Results showed that the heart rate increases for chocking, felling, limbing and bucking were 94.0%, 87.9%, 84.8% and 56.4% respectively. The rate of Work Load Index was higher in the limbing(61.4%) activity than other activities chocking(55.2%), felling(54.1%) and bucking(32.1%). During 50% working heart rate test it was found that limbing(1.09), chocking(1.05) and felling(1.04) was exposed to high work intensity compared to bucking(0.83). The results showed that maximum acceptable work times(felling, chocking and limbing) were 2.30 hour, 1.85 hour and 1.60 hour respectively. To avoid occupational accidents, timber harvest workers may use a suitable working hour schedule to felling, chocking, limbing.

• Journal of Korean Society of Forest Science
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• v.110 no.4
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• pp.711-723
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• 2021

During the COVID-19 pandemic, social distancing affected daily life and leisure activities, including forest recreational activities. This study identified changes in people's participation in forest recreational activities and factors affecting their participation. It collected data from 1,000 samples through an online survey and analyzed it using a binary logit model with interaction terms. It was observed that there were decreases in the participation in visits to urban parks and green areas, outdoor activities in forests and mountains, and trips to mountain villages after the COVID-19 outbreak. People in their 40s, 50s, and 60s were more likely to decrease their participation in all kinds of forest recreational activities than those in their 20s. Moreover, higher household income earners were more likely to decrease their involvement in outdoor activities in forests and mountains. With respect to the place of residence, the residents in the Seoul metropolitan area were less likely to decrease their participation in trips to mountain villages than those outside this area. Thus, this study suggests that online forest recreation information services and forest management are needed to meet the demands of forest recreation for young generations and diversify the function of forests and rural areas as a safe leisurely space.

• Journal of Korean Society of Forest Science
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• v.99 no.3
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• pp.259-266
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• 2010

Forest fire occurrence in Korea is highly related to human activities and its spatial distribution shows a strong spatial dependency with cluster pattern. In this study, we analyzed spatial distribution pattern of forest fire with point pattern analysis considering spatial dependency. Distributional pattern was derived from Ripley's K-function according to causes and distances. Spatially clustered intensity was found out using Kernel intensity estimation. As a result, forest fires in Korea show clustered pattern, although the degrees of clustering for each cause are different. Furthermore, spatial clustering pattern can be classified into two groups in terms of degrees of clustering and distance. The first group shows the national-wide cluster pattern related to the human activity near forests, such as human-induced accidental fire in mountain and field incineration. Another group shows localized cluster pattern which is clustered within a short distance. It is associated with the smoker fire, arson, accidental by children. The range of localized clustering was 30 km. Beyond of this range, the patterns of forest fire became random distribution gradually. Kernel intensity analysis showed that the latter group, which have localized cluster pattern, was occurred in near Seoul with high densed population.

• Journal of the Korean Wood Science and Technology
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• v.32 no.2
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• pp.50-57
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• 2004

This study attempted to evaluate the water repellency and drying effectiveness of linseed oil treated-solid wood at high temperature by immersion. The moisture content of green wood (Pinus densiflora) sample (above 90%) was reduced about 10% after 6 hours treatment at 150℃. When the treated samples were cut into cross section along the length, it was observed that the linseed oil penetrated into up to 20% of the sample cross section area in all locations. However, a strength loss of the specimen was not detected. The pre-drilling before linseed oil treatment was effective in reducing the defects such as checks and splits, and improved the linseed oil penetration into all samples from the surfaces. The result of water absorption test of treated-wood showed that the water repellent efficacy of treated-wood was greater than that of the control. The anti-fungal activity of treated samples using five sap stains and thee decay fungi was not detected in broad-spectrum toxic mechanism. However, decay test using white rot fungi (Tyromyces palustris) and brown rot fungi (Trametes versicolor) showed that the treated sample has a decay resistance to these two fungi.

• Journal of Microbiology and Biotechnology
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• v.18 no.3
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• pp.404-409
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• 2008

The brown-rot basidiomycete Fomitopsis palustris is known to degrade crystalline cellulose (Avicel) and produce three major cellulases, exoglucanases, endoglucanases, and ${\beta}$-glucosidases. A gene encoding endoglucanase, designated as cel12, was cloned from total RNA prepared from F. palustris grown at the expense of Avicel. The gene encoding Cel12 has an open reading frame of 732 bp, encoding a putative protein of 244 amino acid residues with a putative signal peptide residing at the first 18 amino acid residues of the N-terminus of the protein. Sequence analysis of Cel12 identified three consensus regions, which are highly conserved among fungal cellulases belonging to GH family 12. However, a cellulose-binding domain was not found in Cel12, like other GH family 12 fungal cellulases. Northern blot analysis showed a dramatic increase of cel12 mRNA levels in F. palustris cells cultivated on Avicel from the early to late stages of growth and the maintenance of a high level of expression in the late stage, suggesting that Cel12 takes a significant part in endoglucanase activity throughout the growth of F. palustris. Adventitious expression of cel12 in the yeast Pichia pastoris successfully produced the recombinant protein that exhibited endoglucanase activity with carboxymethyl cellulose, but not with crystalline cellulose, suggesting that the enzyme is not a processive endoglucanase unlike two other endoglucanases previously identified in F. palustris.

• Journal of Naturopathy
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• v.7 no.2
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• pp.39-46
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• 2018

Purpose: The purpose of this study was to evaluate the effect of the subjects after visiting the Gyorae forest on the activity of the autonomic nervous system. Methods: Before and after the forest bath, it was measured using a ubiquitous machine. Results: After the bath there was no significant difference in the sympathetic nerve activity (LF) of the control group, but the difference was significant in the experimental group by increasing (p<.038), and in the variance analysis, there was a significant difference between the groups (p<.014), between pre-and post-bath (p<.026), and also between the groups and pre-and post-bath (p<.018). The changes in parasympathetic activity (HF) were not significant in both the control and experimental. In the LF/HF ratio, the experimental group was significantly increased, and in the analysis of variance, there was also significant difference between group and before and after bath (p<.04). Mean pulse rate in the experimental group was a significant increase after bath (p<.026). In the change of pulse standard deviation, the value of the control and the experimental groups by variance analysis was a significant difference between the groups (p<.014). There was no difference between the mean values of the control and the experimental groups in the change of mean heart rate deviation. Conclusions: The autonomic nervous systems were activated after Gyorae forest bathing, where may be useful place for healing.

• Journal of the Korean Wood Science and Technology
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• v.32 no.1
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• pp.59-66
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• 2004

The dried neeldes(1.5 kg) of Juniperus rigida were ground, extracted with acetone-H₂O(7:3, v/v), concentrated, and fractionated with a series of hexane, CH₂Cl₂, EtOAc and water on a separatory funnel. Each fraction was freeze dried to give dark-brown powder and EtOAc and water soluble fractions were chromatographed on a Sephadex LH-20 column using a series of aqueous methanol and ethanol-hexane mixture as eluent. Spectrometric analysis such as NMR and FAB or EI-MS including TLC were performed to characterize the structures of the isolated compounds. The needles of Juniperus rigida contained a large amount of (+)-catechin, quercetin-3-O-α-L-rhamnopyranoside and isoconiferin, in addition to a small amount of umbelliferone and quercetin-3-O-β-D-rutinoside. The antioxidative activities of each fraction and isolated compounds were tested by DPPH radical scavenging method, and EtOAc soluble fraction, (+)-catechin and quercetin-3-O-α-L-rhamnopyranoside were effective.