The Korean Society of Wood Science & Technology

DOI: JKWST Vol.47(No.6) 1-1, 2019

---

한국목재공학회

DOI: JKWST Vol.47(No.6) 1-1, 2019

---

Jong Bum RA

DOI:10.5658/WOOD.2019.47.6.667 JKWST Vol.47(No.6) 667-673, 2019

---

The performance of a wooden deck made of refractory materials that have difficulties in achieving target penetrations as stipulated in the specification and quality standards for treated wood in Korea, was assessed via a case study in this research. A wooden deck built in Jinju in 2009 was selected for this study because of its fabrication method using pressure and treated refractory materials. The penetration and retention analysis did not satisfy the domestic standard for treated wood. Inspection of the deck in 2019 revealed that the deck had been attacked by decay fungi. Cap rails showed much deeper and wider checking on their surface compared with the top and base rails, resulting in a severe fungal attack. The decking boards exhibited severe fungal decay primarily in the end parts. However, the rails and balusters without checks and posts were virtually free of fungal attack irrespective of the preservative penetration measures. Copper content in the soil 5 cm away from the deck was less than 150 mg/kg, implying that copper movement in the soil was very limited. These results suggest that the inhibition of surface propagation and the protection of end surfaces are essential factors in increasing the longevity of treated wooden decks; further, the results also showed that the deck was within an acceptable range from the point of copper contamination.

Jiyoon YANG , Won-Sil CHOI , Jae-Woo KIM , Sung-Suk LEE , Mi-Jin PARK

DOI:10.5658/WOOD.2019.47.6.674 JKWST Vol.47(No.6) 674-691, 2019

---

The aim of this study was to evaluate the anti-inflammatory effects of essential oils extracted from the wood of Chamaecyparis obtusa, Pinus densiflora, Pinus koraiensis, and Larix kaempferi. Essential oils were extracted by hydrodistillation, and their chemical components were determined by GC/MS. Major chemical components of these essential oils were α-cadinol (19.25%), τ-muurolol (14.20%), and α-pinene (13.74%) in C. obtusa; α-pinene (47.16%), longifolene (14.31%), β-phellandrene (11.78%), and β-pinene (11.02%) in P. densiflora; α-pinene (13.49%) and longifolene (10.79%) in P. koraiensis, and geranyl linalool (23.58%) and α-pinene (18.57%) in L. kaempferi. To evaluate the anti-inflammatory effects of essential oils, lipopolysaccharide (LPS)-induced RBL-2H3 mast cells were treated with these essential oils; then, the changes in the mRNA expression level of the cytokines IL-4 and IL-13 were examined. Further, degranulation was evaluated by measuring β-hexosaminidase release. After LPS-induced RBL-2H3 mast cells were exposed to 10-7% of all types of essential oils, the gene expression levels of IL-4 and IL-13 within the cells remarkably decreased. The relative mRNA expression level of IL-4 was 69.6% in P. densiflora, 63.2% in P. koraiensis, 55.1% in C. obtusa, and 45.8% in L. kaempferi compared with that in the group treated with LPS. The mRNA expression level of L-13 should a similar trend. The inhibitory rate of IL-13 mRNA expression of P. densiflora, P. koraiensis, C. obtusa, and L. kaempferi was 57.8%, 57.1%, 51.1%, and 34.5%, respectively. β-Hexosaminidase release significantly decreased following the treatment with the four types of essential oils. The rate of β-hexosaminidase release were 38.1% C. obtusa; 33.0% P. densiflora; 27.4% P. koraiensis; and 9.1% L. kaempferi. Among all types of essential oils, that extracted from P. densiflora wood showed the highest anti-inflammatory activity. These results show that the tested essential oils exert an anti-inflammatory effect through the inhibition of degranulation and expression of cytokines.

Dongmin LEE , Young-Kyoon KIM , Yeong-Suk KIM , Tae-Jong KIM

DOI:10.5658/WOOD.2019.47.6.692 JKWST Vol.47(No.6) 692-699, 2019

---

Elizabethkingia miricola BM10, a symbiotic bacterium, has been isolated from the hindgut of Reticulitermes speratus KMT001, a termite which occurs on Bukhan Mountain in Seoul, Korea. This strain demonstrated a symbiotic characteristic, in that it lacked endo-β-1,4-glucanase activity, in a previous study. The major fatty acids of E. miricola BM10 were iso-C_15:0, iso-C_17:0 3-OH, and summed feature 3 (iso-C_16:1ω7c/C_16:1ω6c). The content of iso-C_17:0 3-OH was higher, while those of ECL 13.566, iso-C_17:11ω9c, and summed feature 4 were lower than the other three type-strains of the Elizabethkingia genus. The 16S rRNA phylogenetic analysis confirmed that E. miricola BM10 is a new species. The whole genome of E. miricola BM10 was sequenced. The average nucleotide identity of strain BM10 as evaluated by pairwise comparison with E. anophelis R26, E. meningoseptica ATCC 13253, and E. miricola GTC 862 was shown to be 91.5%, 81.2%, and 94.29%, respectively. Based on our study results, E. miricola BM10 appears to represent a new strain of the genus Elizabethkingia.

Jung-Ae OH , Jeong-Wook SEO , Byung-Ro KIM

DOI:10.5658/WOOD.2019.47.6.700 JKWST Vol.47(No.6) 700-708, 2019

---

To verify the possibility of using resistograph to estimate the age of big old living trees, we selected three Zelkova serrata and seven Pinus densiflora in Goesan. The mean diameters at breast height of Z. serrata and P. densiflora were 102 (92-116) cm and 80 (65-110) cm, respectively. The heights measured from the ground using a resistograph ranged at 1.2-4.3 m and 0.6-1.1 m for Z. serrata and P. Densiflora, respectively. The most appropriate needle speed to determine tree-ring boundaries for measuring ring width was 1500 r/min for both tree species. Alternatively, the suitable feed speeds for Z. serrata and P. densiflora were 50 cm/min and 150 cm/min, respectively. From the measured data, the mean numbers of tree rings of Z. serrata and P. densiflora were 57 (43-68) and 104 (93-124), respectively, and the mean tree-ring widths were 4.27 mm (3.18-5.09 mm) and 2.93 mm (2.32-3.34 mm), respectively. A comparison between the time series of tree-ring widths by resistograph and that from the local master chronologies tallied for the heartwood part. Finally, this study showed that resistograph can be used to estimate tree ages when a local master chronology is available.

Seung Min YANG , Seok Eon LEE , Hae Keum PARK , Seog Goo KANG

DOI:10.5658/WOOD.2019.47.6.709 JKWST Vol.47(No.6) 709-720, 2019

---

Due to global warming and abnormal climate, the incidence and scale of green tracts in rivers and water intake dam are increasing every year. Therefore, in this study, developed eco friendly positively charged Torrefied Wood Flour(TWF) coagulant by reusing wood damaged by blight as a natural material. In order to evaluate the effect of coagulant on water ecosystem, green algae contaminated water was collected and TOC showed high removal rate of 86% ~ 92% under 1% and 5% TWF C-PAM treatment condition. The NH₃-N showed 53% removal efficiency. The average pH of the polluted water was 7.9 in the case of hydrogen ion concentration, and the pH of the treated water was in the range of 6.5 ~ 7.7, It was found to be suitable for water quality standards. In ecotoxicity tests, all the results of the experiment showed that both the number of green algae and that of treated water were not affected by the survival of the daphnia. Therefore, as a result of the analyzing, developed paste type TWF coagulants is considered to be able to remove algae using natural resources.

Yeonjung HAN , Chang-Deuk EOM , Sang-Min LEE , Yonggun PARK

DOI:10.5658/WOOD.2019.47.6.721 JKWST Vol.47(No.6) 721-731, 2019

---

Air drying depends on species, density, dimension of wood, the geographical location of the air drying yard, and the meteorological factors of air drying site. If there are four seasons with large difference in temperature and humidity like in Korea, the research of the meteorological factors is required in air drying site. In this study, effective air drying days (EADD) of 24 regions in Korea were calculated by using the average monthly temperature, relative humidity, and wind speed. The EADD in 24 regions in Korea was ranged from 239 days to 291 days, with an average 265 days. This result is 5 days increased compared to the average of EADD calculated using the meteorological factors from 1955 to 1984. The results of multiple regression analysis on the EADD and meteorological factors showed that EADD affected in the order of temperature, relative humidity, and wind speed. As a result of dividing Korea into 4 zones of EADD, the zones of EADD were moved northward compared to previous study due to global warming. As basic data for predicting the moisture content (MC) distribution of Korean red pine logs during air drying conducted in Seoul, the average monthly temperature, relative humidity and wind speed for three years from 2016 to 2018 were presented, and the corresponding changes of the equilibrium MC were analyzed.

Yeonjung HAN , Yoon-Seong CHANG , Chang-Deuk EOM , Sang-Min LEE

DOI:10.5658/WOOD.2019.47.6.732 JKWST Vol.47(No.6) 732-750, 2019

---

Air drying was carried out on 15 Korean red pine logs to provide a prediction model of the moisture content (MC) change in the wood during drying. The final MC was 17.4% after 880 days since the beginning of air drying in the summer for 6 Korean red pine logs with 68.7% initial MC. The final MC was 16.0% after 760 days since the beginning of air drying in the winter for 9 Korean red pine logs with 35.8% initial MC. A regression model with R-squared of 0.925 was obtained as a result of multiple regression analyses with initial MC, top diameter, temperature, relative humidity, and wind speed as independent variable and and MC change during air drying as dependent variable. The initial MC and top diameter, which is the characteristic of Korean red pine, have greater effect on the MC decrease during air drying compared to meteorological factors such as the temperature, relative humidity, and wind speed. Two-dimensional mass transfer analysis was performed to predict the MC distribution of Korean red pine logs during air drying. Two prediction models with different air drying days and different meteorological factors for the determination of the diffusion coefficient and surface emission coefficient were presented. The error between the different two methods ranged from 0.1 to 0.8% and the difference from the measured value ranged from 2.2 to 3.6%. By measuring the internal MC during air drying of Korean pine logs with various initial MC and diameter, and calculating the moisture transfer coefficient in wood for each meteorological condition, the error of the prediction model can be reduced.

Sae-Min YOON , So-Hyun PARK , Tea-Jong KIM , Young-Kyoon KIM , Yeong-Suk KIM

DOI:10.5658/WOOD.2019.47.6.751 JKWST Vol.47(No.6) 751-760, 2019

---

Cellulase is an eco-friendly biocatalyst, and its demand is growing in many industrial applications such as food, textile, paper, and bioenergy. Strains with a high cellulase activities are the starting point for the economic production of cellulase. In a previous study, Acanthophysium sp. KMF001 with high cellulase production ability was selected among 54 wood-rotting fungi. In this study, we evaluated the cellulase productivity of Acanthophysium sp. KMF001 quantitatively and analyzed its taxonomic location using a genetic method. Acanthophysium sp. KMF001 showed high cellulase productivity similar to that of Acanthophysium bisporum and was much better than A. bisporum in specific enzyme activity. The 28S rRNA sequence of Acanthophysium sp. KMF001 was similar to that of Acanthophysium lividocaeruleum MB1825, with 98.40% homology. Phylogenetic analysis suggested that Acanthophysium sp. KMF001 is a new strain. In this study, we propose a new strain with high cellulase productivity.

Yoon-Seong CHANG , Yeonjung HAN , Chang-Deuk EOM , Sangjin CHUN , Hwanmyeong YEO

DOI:10.5658/WOOD.2019.47.6.761 JKWST Vol.47(No.6) 761-769, 2019

---

In modern societies, people spend most of their time indoors and the temperature and humidity controlled by electrical appliances have a considerable effect on their emotions and health. However, improper operation of the artificial facilities frequently creates substances that are harmful to our body. The importance of controlling the natural humidity of interior materials has therefore attracted significant attention. This study was aimed at quantifying the hygroscopic property of some interior finishing wooden materials. Dried and heat-treated yellow poplar (Liriodendron tulipifera) lumbers, oriented strand board, and plywood were selected for this experiment. The moisture adsorption and desorption rates of wooden materials were measured (ISO 24353). Furthermore, the effects of morphological, physical and chemical factors, such as surface microstructure, roughness, and functional groups, on the hygroscopicity were evaluated. The results of this study should contribute to improved accuracy of hygroscopic-property assessments performed on wooden interior materials.

The Korean Society of Wood Science & Technology

DOI: JKWST Vol.47(No.6) 770-772, 2019

---

The Korean Society of Wood Science & Technology

DOI: JKWST Vol.47(No.6) 773-773, 2019

---

The Korean Society of Wood Science & Technology

DOI: JKWST Vol.47(No.6) 774-780, 2019

---

The Korean Society of Wood Science & Technology

DOI: JKWST Vol.47(No.6) 781-781, 2019

---