• Journal of Korean Society for Atmospheric Environment
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• 제18권E3호
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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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• 제17권2호
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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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• 제51권2호
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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.

• 한국환경농학회지
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• 제33권3호
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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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• 제38권1호
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• pp.49-55
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• 2010

본 연구에서는 국내 수종 중 낙엽송(Larix Kaemferi Carr)을 대상으로 하여 톱밥의 특성별, 형태별로 나누어서 제조된 목재펠릿의 특성변화를 조사하였다. 제조된 펠릿의 함수율, 밀도, 회분, 흡습율, 발열량을 측정하여 비교하였다. 펠릿제품의 함수율은 6.4~7.31%로 나타나 목재펠릿의 품질기준 1급인 10% 이하를 만족시켰고, 대팻밥으로 제조한 펠릿의 밀도가 가장 높았고, 톱밥의 종류별 제조된 펠릿의 밀도는 큰 차이가 없었으며, 품질규격 1급을 만족시켰다. 회분은 0.2~0.424%로 품질규격 1급인 0.7% 미만의 범주에 속한 것으로 나타났으나, 수피만으로 제조된 펠릿의 회분량은 2.106%로 상당히 높은 값을 보여 1.5% (2급)을 초과하였다. 흡습율은 수피를 사용한 경우 추출물성분에 의해 수분 흡수 저해 효과가 있는 것으로 나타났으며, 제조된 각 펠릿의 발열량 측정결과 품질기준(1급) 4,300 kcal/kg을 넘어섰다.

• Food Science and Biotechnology
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• 제16권6호
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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.

• 보건의료산업학회지
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• 제13권2호
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• pp.135-142
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• 2019

Objectives: 도라지 추출액을 이용하여 구강미생물에 대한 Platycodon grandiflorum 추출물의 항균 효과를 실험하고자 한다. Methods: 항균 활성 및 최소 저해 농도는 한천 희석법을 사용하여 측정하였다. 추출물 (Platycodon grandiflorum 추출물과 껍질이 없는 Platycodon grandiflorum 추출물)을 준비하고 0.0625 mg/ml, 0.125 mg/ml, 0.25 mg/ml, 0.5 mg/ml, 1 mg/ml의 농도로 한천 플레이트를 만들었다. Results: 치아우식균보다 치은염을 유발시키는 A. naeslundii, A. odontolyticus, A. viscosus 세 균주에서 더 우수한 항균효과를 나타내었으며, 껍질이 없는 도라지 추출물 보다 사포닌 함량이 더 많은 껍질이 있는 도라지 추출물에서 우수한 항균효과를 나타낸 것을 확인하였다. Conclusions: 도라지 추출물 결과에서 보듯이 천연 추출물이 구강질환을 유발시키는 치아우식균 및 잇몸질환균에 대해 항균효과가 있을 수 있음을 시사한다.

• Journal of Plant Biotechnology
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• 제50권
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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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• 제24권6호
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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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• 제23권2호
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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.