• Journal of the Korean Wood Science and Technology
• /
• v.37 no.1
• /
• pp.65-72
• /
• 2009

Variation of wood rays within a growth ring and along axial direction in Pinus koraiensis and Larix kaempferi, which are important Korean commercial softwoods, was examined to get some useful information for their effective utilization. Ray height in cell number and ray number per $0.25mm^2$ in tangential section were investigated by optical microscopy. The average heights of uniseriate rays in Pinus koraiensis and Larix kaempferi were 6.3 and 9.1 cells, respectively. The average numbers of uniseriate rays per $0.25mm^2$ in Pinus koraiensis and Larix kaempferi were 6.5 and 7.5, respectively. The average heights of fusiform rays were about 20 cells but were not significantly different in both species. From earlywood to latewood within a growth ring, the heights of uniseriate and fusiform rays decreased but their numbers remained almost constant. Along axial direction, the heights of uniseriate rays in both species increased with the increase of stem height, and the numbers of uniseriate rays per $0.25mm^2$ in Pinus koraiensis were nearly constant from 0.2 m to 5.2 m but increased up to 19.2 m beyond 5.2 m. However, a constant pattern in the numbers of uniseriate rays was not observed in Larix kaempferi. The heights of fusiform rays in both species were the highest in middle part of stems but were the lowest in base and top of trees. In conclusion, the ray variation pattern was comparatively clear within a growth ring but not clear along axial direction.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.22 no.3
• /
• pp.177-186
• /
• 2002

This experiment was conducted to examine possibility and suitability of forest by-product as a roughage source of deer. As a experimental diet, forest by-product silage(FPS) and commercial mixed ration(CMR) were prepared to compare dry matter intake, digestibility, nitrogen balance and feeding behavior in feeding trials with spotted deer. The digestibility of dry matter was higher(P<0.05) in CMR than in FPS. The digestibility of crude protein was higher in CMR than in FPS and there was significant difference(P＜0.05). CMR had more digestibility of crude fiber than FBS but the difference was not significant. Dry matter intake were similar in both diets. Digestible dry matter intake was higher in CMR than FPS, however, there was no significant difference between experimental diets. Nitrogen intake, urinary and digestible nitrogen were significantly higher(P<0.05) in CMR than FPS. The efficiency of nitorgen utilization was higher for FPS than for CMR. Feeding behavior were similar in FPS and CMR. Consequently. It would be expected that FPS that composed with various feed sources can be used as a good roughage source of deer. Because it has high digestibility, dry matter intake and internal availability of nitrogen.

• Journal of Dairy Science and Biotechnology
• /
• v.30 no.1
• /
• pp.45-53
• /
• 2012

Lactobacillus acidophilus isolated from the feces of a 7-day-old breast-fed infant was characterized to examine the scope of its commercial use. Forty-three Lactobacillus strains, which could grow at pH 5.5, were isolated. From these Lactobacillus isolates, 14 Lactobacillus strains were selected, which demonstrated more than 80% viability and homofermentative lactic fermentation. Finally, 9 L. acidophilus strains (NB 201~NB 209) were identified as candidate strains based upon biochemical properties, carbohydrate utilization, and cellular fatty acid composition. L. acidophilus isolates demonstrated a survival rate of more than 80% when exposed to pH 2.5 for 2 h. In particular, L. acidophilus NB 204 showed a strong acid tolerance, with a 71% survival rate even at pH 2.0. L. acidophilus isolates also manifested high bile acid tolerance; more than 87% of the cells survived on agar containing 1% bile extract, except for L. acidophilus NB 206, which showed a 73% survival rate. All L. acidophilus isolates were confirmed to have proteolytic activity; L. acidophilus NB 204 and NB 209 yielded higher levels of TCA-soluble peptides and free amino acids. The ${\beta}$-galactosidase activity of the L. acidophilus isolates was in the range of 1.97~2.45 units/mL.

• Korean Journal of Environmental Agriculture
• /
• v.31 no.4
• /
• pp.293-299
• /
• 2012

BACKGROUND: Soil utilization pattern can be the main factor affecting soil physico-chemical properties, especially in soil phosphorus (P). Understanding the distribution and bioavailability of P is important for developing management to minimize P release from arable soils to environment. This study was conducted to evaluate the potential bioavailability of soil organic P by using phosphatase hydrolysis method. METHODS AND RESULTS: Twenty-four soils from onion-rice double cropping and 30 soils from plastic film house were selected from Changyeong and Daegok in Gyeongnam province, respectively. The P accumulation pattern (total P, inorganic P, organic P, residual P) and water soluble P were characterized. Commercial phosphatase enzymes were used to classify water-extractable molybdate unreactive P from arable soils into compounds that could be hydrolysed by (i) alkaline phosphomonoesterase (comprising labile orthophosphate monoesters), (ii) a combination of alkaline phosphomonoesterase and phosphodiesterase (comprising labile orthophosphate monoesters and diesters), and (iii) phytase (including inositol hexakisphosphate). Available P was highly accumulated with 616 and 1,208 mg/kg in double cropping system and plastic film house, respectively. Dissolved reactive P (DRP) and dissolved unreactive P (DUP) had similar trends with available P, showing 24 and 109 mg/kg in double cropping and 37 and 159 mg/kg in plastic film house, respectively, indicating that important role of dissolved organic P in the environments had been underestimated. From the result of phosphatase hydrolysis, about 39% and 66% of DUP was evaluated as bioavailable in double cropping and plastic film house, respectively. CONCLUSION(S): Orthophosphate monoester and orthophosphate diester accounted for high portion of dissolved organic P in arable soils, indicating that these organic P forms give important impacts on bioavailability of P released from P accumulated soils.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.37 no.6
• /
• pp.696-700
• /
• 2008

The objective of this study was to investigate the genotoxicological safety and biological functions of octadeca-9,12-dienyl-3,4,5-trihydroxybenzoate (GA-LA) in cream-based emulsion for future application as a functional cosmetic material as well as food. GA-LA was synthesized chemically from gallic acid and linoleic acid. The Ames test showed that GA-LA did not have mutagenical toxicity. The control cream-based emulsion containing GA-LA was prepared by commercial method and tested for 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity. Ferric reducing antioxidant power (FRAP) and inhibition effect against tyrosinase of the emulsions were tested for the evaluation of antioxidative and skin-whitening activities. The results showed that DPPH radical scavenging activity in the cream-based emulsion containing GA-LA was higher (52.65%) than that of the control (4.30%). The FRAP value of the sample was 12.85%, however, no activity was found in control. The inhibition effect of tyrosinase showed also a higher value (26.29%) when compared to the control. The results indicate that GA-LA, which showed superior antioxidative and skin-whitening activities in cream-based emulsion, is a useful functional material applicable in cosmetic products as well as food.

• Journal of the Korean Geotechnical Society
• /
• v.20 no.3
• /
• pp.107-117
• /
• 2004

This paper is to investigate the reinforcing effects of newly devised Tire-cell mat made of waste tires in sand. Parametric study on number of connection bolts between Tirecells, relative density of sand, embedded depth, number of reinforced layers and width of Tirecell mat was made by using plate loading tests. It is found that the number of connection bolt was enough to maintain the given pressure. The bearing capacity ratio(BCR), which is defined as the rate of ultimate bearing capacity of reinforced soil to that of unreinforced soil, is the highest at the lowest density. And the reinforcing effect can be obtained in case of embedded depth within 1.0B, where B is loading width. Also settlement reduction is the highest at the lowest density of sand. The effect of number of Tirecell reinforced layers with 0.4B to 0.5B interval is limited to 2 layers and further reinforcing effects can not be obtained beyond 3 layers. Especially, the bearing capacity increased remarkably at 1 layer of reinforcement and the degree of increase was small from 1 layer to 2 layers of reinforcement. The effect of mat width of Tirecell was not significant because of high stiffness of Tirecell although the maximum bearing capacity was shown at the 2.0B mat width and the reinforcing effects of Tirecell, in general, was prominent compared with those of commercial Geoweb.

• Korean Chemical Engineering Research
• /
• v.52 no.1
• /
• pp.45-51
• /
• 2014

This is to study the effects of various pretreatment methods of agricultural residue, corn stover, and to compare the feature and pros and cons of each method including dilute sulfuric acid (DSA), soaking in aqueous ammonia (SAA), and ammonia recycle percolation (ARP). In order to convert corn stover to ethanol, various pretreatments followed by simultaneous saccharification and co-fermentation (SSCF) were tested and evaluated in terms of ethanol yield. With 3%, w/w of glucan loading using ARP-, DSA-, and SAA-treated solids, SSCFs using recombinant E. coli strain (ATCC$^{(R)}$ 55124) with commercial enzymes (15 FPU of Spezyme CP/g-glucan and 30 CBU/g-glucan enzyme loading) were tested. In the SSCF tests, 87, 90, and 78% of theoretical maximum ethanol yield were observed using ARP-, DSA-, and SAA-treated solids, respectively, which were 69, 58, and 74% on the basis of total carbohydrates (glucan + xylan) in the untreated corn stover. Ethanol yield of SAA-treated solid was higher than those of ARP- and DSA-treated solids. In addition, SSCF test using treated solids plus pretreated hydrolysate indicated that the DSA-treated hydrolysate showed the strongest inhibition effect on the KO11 strain, whereas the ARP-treated hydrolysate was found to have the second strongest inhibition effect. Bioconversion scheme using SAA pretreatment and SSCF can make the downstream process simple, which is suggested to produce ethanol economically because utilization of hemicellulose in the hydrolysate is not necessary.

• Journal of the Korean Wood Science and Technology
• /
• v.12 no.1
• /
• pp.11-30
• /
• 1984

This study was executed to offer the basical data needed to the plywood industry as examining on the wood characteristics of veneer species that grow in Korea. According to the aggravation of log import from foreign countries caused by the gradual exhaustion of wood resources in recent years, the study on wood characteristics of veneer species growing in Korea should be carried out preferentially in promotion of the domestic timber utilization and development of it's processing technique for plywood industry. 50 commercial veneer species in this study were selected from 33 genuses, and general macroseopical wood characteristics for them were examined and described by the species. And also keys for the identification based on gross features were briefly prepared and presented by gymnosperm and angiosperm respectively.

• Journal of the Korea Organic Resources Recycling Association
• /
• v.2 no.1
• /
• pp.65-73
• /
• 1994

Earthworm cast was investigated in this study in order to domestically develop inexpensive and safe plug nursery soil. 20,30,40 and 50% of earthworm cast were added to the nursery soil as vegetable plant growth media, in which peatmoss and vermiculite constituted the rest of the soil. The effects of earthworm cast on the growth of pepper (Capsicum annuum L.) seedling were obtained as follows. 1. According to the growth stages, significant differences(p=0.001) were recorded in number of leaves, leaf area and biological dry matter yield per plant(shoor or root dry matter yield per plant). In view of mixing ratios in the nursery soil, number of leaves, leaf area and stem weight per plant showed differences significantly at 1% level and leaf weight, root weight and biological dry weight per plant at 5% level, respectively. 2. The nursery soil with earthworm cast showed increased number of leaves and leaf area per plant compared to the commercial nursery soil particularly in the later stage of this study than in the earlier stage 3. Through the total period of seedling growth, leaf weight, stem weight and root weight per plant in the nursery soil with earthworm cast were genrally higher than those in the control and this trend was apparant in the treatment of more than 40% of mixing ratio with earthworm cast. 4. Although leaf weight per plant was higher than stem weight per plant till the 3rd week, from the 4th week stem weight per plant was getting higher. In the later stage of seedling growth, the stem weight was higher in the earthworm cast mixed treatment than that in the control. 5. There was no significant difference on biological dry matter yield in the earlier stage of this study, however in the later stage, it was higher in the earthworm cast mixed treatment than that in the control.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.30 no.4
• /
• pp.630-634
• /
• 2001

The effect of chitosan on the quality of processed milk was investigated to minimize the microbial spoilage occurred by contaminant bacteria and yeast. Yeast and bacteria isolated from commercial processed milk were identified as Saccharomyces cerevisiae and Pseudomonas fluoresence by Api 20C and 20E Aux kit, respectively. The growth of isolated yeast and bacteria inhibited in YM broth and TSB containing 0.03% chitosan at $25^{\circ}C$ and $37^{\circ}C$ for 24hour, respectively. Viable cells of processed milk artificially contaminated with Saccharomyces cerevisiae and Pseudomonas fluoresence were reduced about 2~3 l$og_{10}$ cycle by addition of 0.03% chitosan pH, acidity and total bacteria were changed from after storage for 10 day at $4^{\circ}C$, 7 day at 1$0^{\circ}C$ and 1day at $25^{\circ}C$in chitosan no added processed milk during storage for 15day. But, The change of physico-chemical and microbiological charcteristics could not observe in 0.3% chitosan added processed milk during storage 15 day at $4^{\circ}C$, 1$0^{\circ}C$ and $25^{\circ}C$, respectively. The sensory quality of processed milk with 0.3% chitosan was different significantly from control in taste, texture and overall acceptability(p<0.05).