• Korean Journal of Microbiology
• /
• v.48 no.2
• /
• pp.73-78
• /
• 2012

We previously reported that the truncated Cel44C-$Man26A_{P558}$ ${\beta}$-glycosyl hydrolase protein exhibits multifunctional activities, including cellulase, xylanase, and lichenase. DNA shuffling of the truncated Cel44C-$Man26A_{P558}$ enzyme was performed to enhance the enzymatic activity of the multifunctional ${\beta}$-glycosyl hydrolase. Two mutant enzymes, M2Cel44C-$Man26A_{P558}$ that carries one mutation (P438A) and M21Cel44C-$Man26A_{P558}$ that carries two mutations (A273T and P438A) were obtained. The enzymatic activity of the M21Cel44C-$Man26A_{P558}$ double mutant was lower than enzymatic activity of the single mutant (M2Cel44C-$Man26A_{P558}$). However, both mutants displayed the enhancements in their enzyme activities that were ${\approx}1.3$- to 2.2-fold higher than the original enzymatic activity in Cel44C-$Man26A_{P558}$. In particular, the mutant M2Cel44C-$Man26A_{P558}$ exhibited an approximate 1.5- to 2.2-fold increase in the cellulase, xylanase, and lichenase activities in comparison with the control (Cel44C-$Man26A_{P558}$). The optimum cellulase, linchenase, and xylanase activities of ${\beta}$-glycosyl hydrolase were observed at pH 7.0, pH 7.0 and pH 6.0, respectively. These results, therefore, suggest that the amino acid residue Ala438 plays important roles in the enhancement of the activity of multifunctional ${\beta}$-glycosyl hydrolase.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.27 no.3
• /
• pp.209-218
• /
• 2007

This experiment was conducted to investigate effect of plowing frequency and sowing dates on the agronomic characteristics, feed value, weed yield and palatability of silage corn. Treatments were a basal treatment(C: May 5 seeding, plowing once, weeding control once), T1(May 12 seeding, plowing twice, weeding control 0 time), T2(May 19 seeding, plowing three times, weeding control 0 time, T3(May 26 seeding, plowing four times, weeding control 0 time) and T4(June 2 seeding, plowing five times, weeding control 0 time). The experiment was performed at the College of Life and Natural Sciences of Sangju University in Sangju in 2006. The plant height and ear height showed highly in order to C > T1 > T2 > T3 > T4 treatment, leaf length was the highest at T2 (96.0cm). Leaf width and number of dead leaf were the highest at C and T3 (11.2cm), C, C and T1 (4.6), respectively. Stem diameter was the highest at T3 as 31mm, while T2 was the lowest as 25mm (p<0.05). Ear circle showed highly in order of C > T1 > T4 > T3 > T4 (p<0.05), and tip filling degree was the highest at C treatment as 8.8, while T4 treatment was the lowest as 6.0 (p<0.05). The stem hardness and grain hardness were C < T1 < T2 < T3 < T4 (p<0.05). Stem saccharinity was T1(6.1%) was the highest, while T2(3.0%) was the lowest(P<0.05). Fresh yield of weed was the lowest at C treatment as 500 kg/ha, but T1 treatment was the highest as 44,100 kg/ha (p<0.05). Weed coverage rate showed highly in order of T1 > T2 > T3 > T4 > C treatment (p<0.05). Fresh yield of corn was the highest at C treatment as T3,550 kg/ha, but T4 treatment was the lowest as 65,500 kg/ha (p<0.05). Dry matter yield of corn showed highly in order of C(26,978 kg/ha) > T1(26,130 kg/ha) > T2(20,255 kg/ha) > T3(20,255 kg/ha) > T4(17,508 kg/ha) treatment (p<0.05). Crude protein content was T1(7.69%) > T4(7.42%) > T2(6.34%) > T3(5.99%) > C(5.91%) treatment (p<0.05), and Crude fat content showed highly in order of C (2.13%) > T1(2.04%) > T2(1.96%) > T3(1.95%) > T4(1.84%) treatment. Relative palatability of Holstein, Korean native goat and spotted deer was the highest at C treatment, but Korean native cattle was the highest at T1 treatment.

• KSBB Journal
• /
• v.10 no.5
• /
• pp.575-581
• /
• 1995

A plasmid pTTY2, containing the lipase-producing gene, was used to transform an E. coli phage lysogen, P90c/$\phi$434, into the lipase-producing lysogen, P90c/$\phi$434/pTTY2. After the overproduction of lipase by the isopropylthio-${\beta}$-D-galactoside induction, the prophage $\phi$434 in the chromosome of the host cell was induced by the milomycin C addition or ultraviolet irradiation to lyse the host cell. The optimum operating conditions, such as the isopropylthio-${\beta}$-D-galactoside induction period and the phage induction timing, were sought for the efficient cell lysis in the same fermenter. Effective cell lysis occurred at the earlier exponential growth phase with the isopropylthio-${\beta}$-D-galactoside induction period of 1 hour. The amount of the lipase production was qualitatively measured by the halo size in Luria-Bertani agar medium containing tributyrin and Rhodamine B plate.

• Journal of Animal Environmental Science
• /
• v.16 no.2
• /
• pp.143-152
• /
• 2010

Conditions for artificial culture of Lemna Paucicostata and its nutritional values were examined in this study. Lemna P. was cultured using artificial wastewater and a bioreactor (total volume $2,630\;cm^3$, working volume $2,240\;cm^3$) was operated at conditions of 6,250 lux and $28^{\circ}C$. Water flow affected the growth of Lemna P.: growth rate was very high (more than $1.1\;d^{-1}$) at a condition of no-water movement, but it was very low (less than $0.15\;d^{-1}$) when water moved slowly. The growth of Lemna P. was higher in $16h\;d^{-1}$ light cycle than in Sand $24h\;d^{-1}$, and it was also severely affected by the initial $NH_4$-N levels of wastewater. The growth rate of Lemna P. was high in lower $NH_4$-N level, indicating that the growth rate is in inverse proportion to $NH_4$-N concentration in wastewater. However, the contents of crude protein (CP) of Lemna P. were proportional to the initial $NH_4$-N concentration. The CP contents of Lemna P. cultured at 2, 10, 50 and 100 $NH_4$-N mg $L^{-1}$ was 18, 24, 37, 43%, respectively, showing the Lemna P. cultured at 50 and $100\;mg\;L^{-1}$ had similar protein contents to linseed (CP 35%), cottonseed (CP 38%) and soybean (CP 45%). Fat, protein, fiber, NDF and ADF contents of Lemna P. harvested at conditions of $16h\;d^{-1}$ light cycle and less than $2\;mg\;L^{-1}$ of $NH_4$-N level was 2.8, 18, 27, 20, 41 and 65.7%, respectively. Since the growth rate of Lemna P. was very high (more than $1.1\;d^{-1}$) at those conditions, it was convinced that mass production of valuable protein and fiber sources are feasible. In particular, since the Lemna P. has unsaturated fatty acids found mainly in animal fat as well as beneficial fatty acids to health such as C18:ln9c, C18:2n6c, C20:5n3 and C22:2, the Lemna P. biomass would be a highly valuable alternative feed source to grains.

• Journal of Gastric Cancer
• /
• v.6 no.3
• /
• pp.146-153
• /
• 2006

Purpose: Gastrointestinal stromal tumorsm (GISTs) are the most common mesenchymal tumors that arise anywhere in the tubular GI tract. The prognosis for GSTIs is important because f GISTs may metastasiwx in the liver or the abdominal cavity in an early stage. For the reason we examined the tumor size, the mitotic number, ki 67, p53, and c-kit mutation as independent prognostic factor for GISTs. Materials and Methods: A retrospective study was conducted in 76 patients who had been re-evaluated for confirmation of diagnosis between Jan 1998 and Dec. 2001. at Catholic University of medicine. Results: There were significant difference between the turner size, mitotic indices, ki 67, c-kit mutations and the 5-years survival rates. Tumor size (${\geq}5\;cm$) and mitotic index (${\geq}5/50\;HPF$) were statistically related to a significantly poor prognosis (P=0.017 and P=0.042, respectively). c-kit mutations in exon 11 were found in 7 cases c-kit mutation was observed more frequently in high risk patients, and there was a significant difference between c-kit mutation and survival (P=0.037). Elevated ki 67 was noted in 34 out of the 76 cases. High risk patients showed elevated ki67 index more frequently and there was significant relation with the survival rate (P=0.0417). Conclusion: We think that tumor size, mitotic index, Ki 67 and c-kit mutation are as independent prognostic factors for GISTs, but more research is needed.

• Journal of the Korean Applied Science and Technology
• /
• v.22 no.4
• /
• pp.339-348
• /
• 2005

On the analysis of triacylglycerol (TG) from the kernels of Acanthopanax sessiliflorus by reversed phase-HPLC, it was separated into three main fractions of PN 44, 46 and 48, according to partition number (PN). On the contrary, it could be clearly classified into seven fractions of SMM, MMM, SMD, MMD, SDD, MDD and MDT by silver ion-HPLC by the number of double bond in the acyl chains of TG species. But resolution of so-called critical pairs of TG molecular species such as molecular pairs of $P_eLL$ $[C_{18:1{\omega}12}/(C_{18:2{\omega}6)2}]$ and OLL $[C_{18:1{\omega}9}/(C_{18:2{\omega}6)2}]$ and OOL $[(C_{18:1{\omega}9)2}/C_{18:2{\omega}6]$, and $P_eP_eL$ $[(C_{18:2{\omega}12)2}/C_{18:1{\omega}6]$ was not achieved $(P_e;$ petroselinic acid, L; linoleic acid, O; oleic acid). On the other hand, TG extracted from Aralia continentalis kernels were also fractionated into seven groups of SSM, SMM, MMM, SMD, MMD, SDD and MDD (S; saturated acid, M; monoenoic acid, D; dienoic acid) by silver ion-HPLC, although it's were classified into three groups of PN 44, 46 and 48 by reversed phase-HPLC. The fractions of SMM, MMM, MMD and MDD were divided into two subfractions, respectively; the fractions of SMM, MMM, MMD and MDD were resolved into the subfraction of $PP_e/P_e$ and POO (critical pairs from each other), that of $P_e/P_e/P_e$ and OOO, that of $P_e/P_e/L$ and OOL, and that of $P_e/L/L$ and OLL.

• Communications of the Korean Mathematical Society
• /
• v.35 no.1
• /
• pp.1-12
• /
• 2020

A pathos block line cut-vertex graph of a tree T, written P BL_c(T), is a graph whose vertices are the blocks, cut-vertices, and paths of a pathos of T, with two vertices of P BL_c(T) adjacent whenever the corresponding blocks of T have a vertex in common or the edge lies on the corresponding path of the pathos or one corresponds to a block B_i of T and the other corresponds to a cut-vertex c_j of T such that c_j is in B_i; two distinct pathos vertices P_m and P_n of P BL_c(T) are adjacent whenever the corresponding paths of the pathos P_m(v_i, v_j) and P_n(v_k, v_l) have a common vertex. We study the properties of P BL_c(T) and present the characterization of graphs whose P BL_c(T) are planar; outerplanar; maximal outerplanar; minimally nonouterplanar; eulerian; and hamiltonian. We further show that for any tree T, the crossing number of P BL_c(T) can never be one.

• Journal of Applied Biological Chemistry
• /
• v.61 no.1
• /
• pp.59-67
• /
• 2018

This study was conducted to isolate the cellulolytic bacteria able to grow on LB- Carboxymethyl cellulose (CMC) agar trypan blue medium from the mixed forest and Larix leptolepis stands. Three bacterial strains with high activity against both CMC and xylan were isolated. Both API kit test and 16S rRNA gene sequence analysis revealed that the three different isolates belong to the gene Bacillus. Therefore, the isolates named as Bacillus sp. EFL1, Bacillus sp. EFL2, and Bacillus sp. EFP3. The optimum growth temperature of Bacillus sp. EFL1, EFL2, and EFP3 were $37^{\circ}C$. The optimum temperature for CMCase and xylanase from Bacillus sp. EFL1 were $50^{\circ}C$. The optimum pH of Bacillus sp. EFL1 xylanase was pH 5.0 but the optimum pH of CMCase from Bacillus sp. EFL1 was pH 6.0. The optimum temperature of CMCase and xylanase from Bacillus sp. EFL2 was $60^{\circ}C$, respectively. The optimum pH of CMCase of Bacillus sp. EFL2 was 5.0, whereas xylanase showed high activity at pH 3.0-9.0. The optimum temperature for CMCase and xylanase of Bacillus sp. EFP3 was $50^{\circ}C$. The optimum pH for CMCase and xylanse was 5.0 and 4.0, respectively. CMCases from Bacillus sp. EFL1, EFL2, and EFP3 were thermally unstable. Although xylanase from Bacillus sp. EFL1 and EFP3 showed to be thermally unstable, xylanase from Bacillus sp. EFL2 showed to be thermally stable. Therefore, Bacillus sp. EFL2 has great potential for animal feed, biofuels, and food industry applications.

• Communications of the Korean Mathematical Society
• /
• v.18 no.4
• /
• pp.695-701
• /
• 2003

In this paper, we have characterizations of almost P-spaces which are analogous characterizations of P-spaces and we will show that if X is an almost P-space such that it is $C^{*}-embedded$ in every almost P-space in which X is embedded, then $$\mid${\upsilon}X-X$\mid${\leq}1$ and that if $$\mid${\upsilon}X-X$\mid${\leq}1$ and ${\upsilon}X$ is Lindelof, then for any almost P-space Y in which X is dense embedded, then X is $C^{*}-embeded$ in Y.

• Journal of Korean Society of Forest Science
• /
• v.108 no.1
• /
• pp.21-28
• /
• 2019

This study was conducted to determine the carbon (C) and nitrogen (N) response of litterfall components as affected by N addition in compound fertilizer in a Korean red pine (Pinus densiflora S. et Z.) stand in southern Korea. Litterfall in a mature red pine stand was collected for two years following compound fertilizer application ($N_3P_4K_1$; $P_4K_1$) and no fertilization (control). The C concentration of litterfall components was not significantly (P > 0.05) different between the $N_3P_4K_1$ and the control plots, whereas the N concentration of the litterfall components was significantly higher in the $N_3P_4K_1$ plot than in the control plot. The $N_3P_4K_1$ and $P_4K_1$ additions induced a lower C/N ratio of litterfall components compared with the control plot. Annual C and N fluxes via litterfall components were not affected by the $N_3P_4K_1$ addition over the study period, except for reproduction litter. Annual N fluxes via reproduction litter were significantly higher in the $N_3P_4K_1$ plot than in the control plot. Thus, the $N_3P_4K_1$ and $P_4K_1$ additions could modify differently nutrient distribution of the forest floor and mineral soils in a red pine stand. These results indicate that N concentration and C/N ratio in litterfall components are more susceptible to fertilizer application than the C response in litterfall components.