• Journal of Korean Society for Atmospheric Environment
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• v.18 no.E3
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• pp.153-163
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• 2002

A laboratory- scale dual-column biofilter system was used to study the biofiltration of dimethyl disulfide (DMDS). The gas flow rate and DMDS concentration to the biofilter were varied to study their effect on the remov-al of dimethyl disulfide. Operating parameters such as pH, temperature, and water content were monitored during the biofilter operation and necessary precautions were taken to keep these parameters within the acceptable limits. It was observed that the removal efficiency of DMDS was optimal at neutral pH values. After five month op-eration, the neutralization of the filter beds with sodium carbonate became necessary for the optimum operation of the biofilters. The microbial population already present in the compost mixtures was found to be adequate in treat-ing DMDS. The compost mixtures were found to be similar in terms of biofiltration efficiency of DMDS. However, pressure drops observed in the first column compost mixture (compost/ peat mulch) was extremely high, making this compost economically not feasible. The second mixture (compost/bark) provided pressure drops within accept-able limits. A minimum residence time of 30 seconds at the optimal operating conditions appeared to be adequate for achieving high removal efficiencies (>90%).

• Preventive Nutrition and Food Science
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• v.17 no.2
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• pp.116-121
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• 2012

Water extract from Pinus densiflora (WPD) was investigated for its antioxidant activity and its ability to provide protection from DNA damage. A series of antioxidant assays, including a 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical-scavenging assay, a reducing power assay, a metal-chelating assay, a superoxide radical scavenging assay, and a nitrite scavenging ability, as well as a DNA damage protection assay were performed. Total phenolic content was found to be 211.32 mg Tan/g WPD. The extract scavenged 50% DPPH free radical at a concentration of 21.35 ${\mu}g/mL$. At that same concentration, the reducing power ability of WPD was higher than that of ${\alpha}$-tocopherol. The extract chelated 68.9% ferrous ion at the concentration of 4 mg/mL. WPD showed better nitrite scavenging effect at the lower pH. Meanwhile, WPD exhibited a strong capability for DNA damage protection at 1 mg/mL concentration. Taken together, these data suggest water extract from Pinus densiflora could be used as a suitable natural antioxidant.

• Journal of the Korean Wood Science and Technology
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• v.51 no.2
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• pp.81-97
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• 2023

The aim of this study were to evaluate tannin resorcinol formaldehyde (TRF) for the preparation of cross-laminated timbers (CLTs) made from fast-growing tree species and to analyze the physical and mechanical properties of CLTs. TRF copolymer resin was prepared by using the bark extracts of Swietenia mahagoni (L.) Jacq. It was observed that the TRF adhesive possessed less solid content (23.59%), high viscosity (11.35 poise), and high pH values (10.0) compared to the standard phenol resorcinol formaldehyde. The TRF adhesive was applied to produce CLTs with the addition of 15% tapioca and flour as an extender. The six-layered CLTs were produced from sengon (Falcataria moluccana Miq.), jabon [Anthocephalus cadamba (Roxb) Miq.], coconut (Cocos nucifera L.), and the combination of coconut-jabon and coconut-sengon wood. The analysis of variance revealed that the layer composition of CLT significantly affected the physical and mechanical properties of the beam. While the modulus of rupture met the standard, the moisture content and modulus of elasticity values did not fulfill JAS 1152-2007. All of the CLTs produced in this study demonstrated low formaldehyde emission, ranging from 0.001 mg/L to 0.003 mg/L, thereby satisfying the JAS 1152 for structural glue laminated timber.

• Korean Journal of Environmental Agriculture
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• v.33 no.3
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• pp.178-183
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• 2014

BACKGROUND: The white stain symptom of grape clusters and canes by dust-like particles occurred in many vineyards recently. This study was conducted to investigate the ecological characteristics of white stain symptom in grapevines and vineyards. METHODS AND RESULTS: Optimal climate condition for white stain symptom was $25^{\circ}C{\sim}30^{\circ}C$ with 60% of humidity. Moreover, closed condition with same humidity showed higher incidence rate of white stain symptom than ventilation condition. Grape varieties with black berry skin such as Campbell-Early and Kyoho were more sensitive to white stain symptom compare to varieties with green and red berry skin. Although the pathogens were not detected until March, they increased from April, and increased sharply from mid of July. The pathogens may overwinter in the infected stems and/or on the bark as a mycelium. According to the increase of sugar content of grape from August to September, the mycelium which was parasitic on the bark grew to move to the fruits through the stems, and finally reached the fruit stalk to detach berries from the clusters. CONCLUSION: Well ventilation is recommended inside the vineyard since mid-July with roll up an insect net. In addition, infected stems and fruits should be removed out from grapevines infected with pathogens in the vineyards.

• Journal of the Korean Wood Science and Technology
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• v.38 no.1
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• pp.49-55
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• 2010

morphologically different Larix Kaemferi Carr sawdust. The pellet characteristics included moisture contents satisfied the first grade (less than 10%) of quality standard of wood pellets announced by Korea Forest Research Institute. Densities were also adequate for the first grade (640kg/$m^3$) on the quality standard and there was no large difference in other characteristics of pellets, however, pellets manufactured with planer shavings had the highest density. Ash contents also passed the first grade (less than 0.7) of quality standard. But bark pellet exceeded the second grade (1.5%) in ash content. Lower absorption ratio of bark pellet showed the effect on hygroscpicity. The heating value of the manufactured wood pellets in this study exceeded the first grade of quality standard(more than 4,300 kcal/kg).

• Food Science and Biotechnology
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• v.16 no.6
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• pp.935-942
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• 2007

The stem bark of Rhus verniciflua (RVSB) has been used in herbal medicine to treat diabetes mellitus and stomach ailments for thousands of years in Korea, despite its content of the plant allergen, urushiol. A new biological approach for the removal of urushiol from RVSB using mushrooms is described. All mushroom species (11 sp.) employed in this study were able to grow on RVSB, although the growth rate (mm/day) was lower than the control (sawdust). The components of urushiol congeners [C15 triene (m/z 314), C15 diene (m/z 316), C15 monoene (m/z 318), and C15 saturated (m/z 320)] were purified by HPLC and identified by GC-MS. A C15:3 (3-pentadecatrienly catechol) was found to be most abundant in RVSB. Urushiol analogues decreased remarkably from 154.15 to 10.73 mg/100 g (approximately 93%) by Fomitella fraxinea, whereas Trametes vercicolor showed only a 1.46% degradation capacity despite its 2 fold higher growth rate. Similarly, laccase activity was found to be high for F. fraxinea and low for T. vercicolor. Moreover, approximately 98% detoxification was accomplished by F. fraxinea cultivated on RVSB supplemented with 20%(w/w) rice bran. These findings suggest that mushrooms can be used in the detoxification of RVSB.

• The Korean Journal of Health Service Management
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• v.13 no.2
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• pp.135-142
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• 2019

Objectives: The objective of this study was to assess the antimicrobial effect of Platycodon grandiflorum extracts against oral microorganisms. Methods: The anti-microbial activity and minimal inhibitory concentration were measured the agar dilution method. Results: Platycodon grandiflorum extracts grew in the free agar plates all of the oral microorganisms. In the bark-free Platycodon grandiflorum extracts all the oral microorganisms grew in the free agar plates. Growth was inhibited at a concentration of 0.5 mg/ml. Oral microorganisms showed an absence of growth at a concentration of 1 mg/ml. Conclusions: It was confirmed that the extracts of Platycodon grandiflorum having a higher saponin content than the bark - free Platycodon grandiflorum extract showed excellent antimicrobial effect.

• Journal of Plant Biotechnology
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• v.50
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• pp.97-107
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• 2023

Malaria remains to be one of the most severe global public health concerns. Traditionally, Aspilia Africana and Warburgia ugandensis have been used to treat malaria in several African countries for millennia. In the current study, A. africana calli (AaC), A. africana in vitro roots (AaIR), A. africana wild leaf (AaWL), and W. ugandensis stem bark (WuSB) were dried and pulverized. Fourier transform near-infrared spectroscopy was used to analyze the powdered samples, while 80% ethanolic extracts of each sample were assayed for antiplasmodial activity (against Plasmodium falciparum strains DD2 (chloroquine-resistant) and 3D7 (chloroquine-sensitive)) and cytotoxicity. WuSB showed the highest antiplasmodial activity (IC₅₀ = 1.57 ± 0.210 ㎍/ml and 8.92 ± 0.365 ㎍/ml against P. falciparum 3D7 and DD2, respectively) and selectivity indices (43.90 ± 7.914 and 7.543 ± 0.051 for P. falciparum 3D7 and DD2, respectively). The highest total polyphenolic contents (total phenolic and flavonoid contents of 367.9 ± 3.55 mg GAE/g and 203.9 ± 1.43 mg RUE/g, respectively) were recorded for WuSB and the lowest were recorded for AaC. The antiplasmodial activities of the tested plant tissues correlated positively with total polyphenolic content. The high selectivity indices of WuSB justify its traditional applications in treating malaria and present it as a good candidate for discovering new antimalarial compounds. We recommend elicitation treatment for AaIR, which showed moderate antiplasmodial activity against P. falciparum DD2, to increase its secondary metabolite production for optimal antimalarial activity.

• The Korean Journal of Ecology
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• v.24 no.6
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• pp.381-384
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• 2001

A preliminary comparative histodimensional studies, such as wood to bark ratio, total area of parenchyma cells and bast fibers, height and diameter of vascular rays, pith diameter and phenological parameters, height of the plant, perimeter of the stem, dry weight of the stem and leaves have been investigated for the low and high rubber bearing Guayule plants growing in same and different climatic regions of India. A plausible correlation is found between the percentage of rubber content and anatomical characters in the investigated varieties.

• Natural Product Sciences
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• v.23 no.2
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• pp.146-150
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• 2017

Alnus sibirica (AS) geographically distributes in Korea, Japan, Northeast China and Russia. The bark of this plant had been used for antipyretic, expectorant, anti-phlogistic, antitussive, anti-asthmatic and as a health tea for alcoholism. Recently, we studied various biological activities of AS and the isolated diarylheptanoid. In present study, we conducted fermentation of AS (FAS) and isolated two diarylheptanoid (hirsutenone and muricarpone B). Moreover, we established the validation and contents determinations of the two compounds by HPLC on FAS.