• Proceedings of the SOHE Conference
• /
• 1997.12a
• /
• pp.45-49
• /
• 1997

To study the effect of amylose on the mechanism of gel formation, swelling power, water solubility, the pattern of alkali gelatinization and gel properties were investigated. The swelling power of waxy maize starch(Amioca) was the highest and followed by those of PFP ＞Amaizo ＞ Amylomaize Ⅶ. Amioca showed higher iodine affinity of soluble amylose than other maize starches. The apparent viscosity of alkali gelatinization measured by Brookfield viscometer for Amaizo was $70{\pm}10^3cp$ which was higher than Amylomaize VII. The apparent viscosity of PFP was increased to $70{\pm}10^3cp$ and then decreased. As maize starches were autoclaved at $121^{\circ}C$ with starch : water ratio (1:9) and autoclaving-cooling cycle were up to 4 times, gel properties were measured by rheometer. Amaizo showed the highest value for hardness, adhesiveness, springiness, cohesiveness, and hardness of gel after two times of autoclaving-cooling cycles was the highest. Gel properties was thus affected by the chain length of amylose rather than amylose content.

• Bulletin of the Korean Chemical Society
• /
• v.32 no.11
• /
• pp.3973-3978
• /
• 2011

The reductive pinacol coupling reaction of aldehydes or ketones creating a new C-C bond has been a major tool to produce 1,2-diol compounds. The reaction mechanism is known to be composed of sequential three steps (activation, coupling, and dissociation). In this work, we studied the dissociation step of half-titanocene-based catalytic systems. Cp and $Cp^*$ derivatives of the pinacolato-bridged dinuclear complex were synthesized and evaluated as possible models for intermediates from the coupling step. We monitored $^1H$-NMR spectra of the reaction between the metalla-pinacol intermediates and $D_2O$. New reaction routes of the dissociation step including oxo- and pinacolato-dibridged dinuclear complexes and oxo-bridged multinuclear complexes have been suggested.

• Journal of the Korean Chemical Society
• /
• v.52 no.5
• /
• pp.476-481
• /
• 2008

• Parasites, Hosts and Diseases
• /
• v.40 no.1
• /
• pp.59-64
• /
• 2002

A Cryptosporidium parvum sporozoite and oocyst λgt11 cDNA library was screened with a hyperimmune rabbit serum that was developed against insoluble fragments of ultrasonicated oocysts. A clone named Cp22.4.1 encoding a protein of 231 amino acids with 4 zinc-finger domains characterized by a Cys-X2-Cys-X4-His-X4-Cys motif was isolated and characterized. There was a complete match between the sequencing data of the coding region of Cp22.4.1 and the corresponding gene at chromosomal level. Cloning in a pBAD-TOPO-TA expression vector permitted to evaluate the antigenicty of the recombinant His-tagged antigen. This antigen was recognized by 2 out of 5 sera from Cruptosporidium immune calves and not by sera from parasite naive animals.

• Asian-Australasian Journal of Animal Sciences
• /
• v.8 no.2
• /
• pp.163-169
• /
• 1995

This study was conducted 1) to compare the nutrient content and mineral composition of the Philoppine indigenous sheep and goats diets when grazed in common pasture during rainy season, 2) to determine the influence of sampling methods on nutrient content and mineral composition of upland (UP) and lowland (LP) native pastures, and 3) to compare these two pasture types in terms of nutrient and mineral composition. Experiment 1 used sis esophageally fistulated animals, three each for sheep and goats. Weekly extrusa collection was done for a period of three months. Experiment 2 was conducted in UP and LP; these were sampled thrice by three methods, plucking, clipping and use of three esophageally fistulated sheep. Results of Experiment 1 indicated that the diets of sheep were greater in crude protein(CP; p < 0.01) and ether extract(EE; p < 0.05) but lower in crude fiber (CF) and acid detergent lignin (ADL; p < 0.05) than that of goat diets. All other nutrient fractions including mineral composition were not significantly different from each other. Significant findings of Experiment 2 were: CP content of UP was in the order fistulated > plucked > clipped (p < 0.05); CP content of LP was greater (p <0 .05) in fistulated and plucked samples; and ash content was greater (p < 0.05) in fistulated samples of both pastures. The CP of UP was different (p < 0.05) from each sampling method but the CP of LP and ADL of both pastures were greater (p < 0.05) in clipped samples. Most minerals either macro or microminerals were greater in fistulated samples of both pastures. Pooled data of the two pastures showed that LP had better nutrient characteristics and greater mineral composition. Based from this study, there were few differences between the diets of indigenous sheep and goats when grazed in common pasture. Also, sampling methods influenced the nutrient composition of indigenous sheep diets.

• Bulletin of the Society of Naval Architects of Korea
• /
• v.6 no.1
• /
• pp.25-34
• /
• 1969

From viewpoints of over-all ship economy the straight framed V-bottom hull forms with chines are considered to be attractive even for usual commercial vessels, because increments of resistance over that of round hull forms, if any, can be well compensated with reduction in construction cost.[1] To investigate the influences of both prismatic coefficient and chine elevation on resistance performance, three models of straight-framed V-bottom hull forms which are similar to Prof. C. Ridgely-Nevitt's W-18, W-8, and W-20[2],[3] in size and hull form coefficients were tested at the SNU Ship Model Towing Tank for resistance measurements. They are of Cp=0.60, 0.65 and 0.70 and of ${\Delta}/(0.01L)^3=300$. Influence of variation of chine elevation on resistance performance were observed with the test results obtained at normal condition, and at the trimed by the stern by 2% and 4% of $L_{bp}$ at normal condition under same displacement. The hull form characteristics are shown in Table 1, and in Fig. 1, 2, 3, 4 and 5. The test results are shown in Fig 8, 9 and 10 in the form of Cr vs. $V/\sqrt{L}$ curves taking Cp as a parameter for normal condition, trim by the stern in 2% and 4% $L_{bp}$ at normal condition , respectively. Cr vs. $V/\sqrt{L}$ curves taking trim condition as a parameter are also shown in Fig 11, 12 and 13 for Cp=0.60 and 0.70, respectively. The best and the worst trim condition at given $V/\sqrt{L}$ in viewpoint of Cr are plotted for each Cp-value as shown in Fig 14, 15 and 16. From the above results the following conclusions are derived: (1) In general, the resistance performance of the straight-framed V-bottom hull forms are not inferior to those of round hull forms. At a certain range of $V/\sqrt{L}$ the former gives less resistance than the latter. (2) Regarding influences of Cp on Cr, it is observed that, at $V/\sqrt{L}$ less than about 0.925, the greater Cp-value gives the more increment of Cr, and that, at $V/\sqrt{L}$ greater than about 0.925 the smaller Cp-value gives the more increment of Cr. It is also noteworthy that the model of Cp=0.70 has remarkable hump on Cr vs. $V/\sqrt{L}$ curve between $V/\sqrt{L}=0.80$ and 0.90. (3) For higher speed within the test range, the chine elevation having the steeper slope around bow and the easier slope around amidship and stern, refered to watering, give the better results in resistance performance. (4) Assuming the chine elevations adopted for the tested models were not of the best, we would expect further improvement of resistance performance for such form. Hence, a systematic study on chine elevation is very disirable to prepare design data of general purpose for the such hull forms.

• Journal of Microbiology and Biotechnology
• /
• v.34 no.2
• /
• pp.457-466
• /
• 2024

Cellobiose dehydrogenases (CDHs) are a group of enzymes belonging to the hemoflavoenzyme group, which are mostly found in fungi. They play an important role in the production of acid sugar. In this research, CDH annotated from the actinobacterium Cellulomonas palmilytica EW123 (CpCDH) was cloned and characterized. The CpCDH exhibited a domain architecture resembling class-I CDH found in Basidiomycota. The cytochrome c and flavin-containing dehydrogenase domains in CpCDH showed an extra-long evolutionary distance compared to fungal CDH. The amino acid sequence of CpCDH revealed conservative catalytic amino acids and a distinct flavin adenine dinucleotide region specific to CDH, setting it apart from closely related sequences. The physicochemical properties of CpCDH displayed optimal pH conditions similar to those of CDHs but differed in terms of optimal temperature. The CpCDH displayed excellent enzymatic activity at low temperatures (below 30℃), unlike other CDHs. Moreover, CpCDH showed the highest substrate specificity for disaccharides such as cellobiose and lactose, which contain a glucose molecule at the non-reducing end. The catalytic efficiency of CpCDH for cellobiose and lactose were 2.05 × 10⁵ and 9.06 × 10⁴ (M^-1 s^-1), respectively. The result from the Fourier-transform infrared spectroscopy (FT-IR) spectra confirmed the presence of cellobionic and lactobionic acids as the oxidative products of CpCDH. This study establishes CpCDH as a novel and attractive bacterial CDH, representing the first report of its kind in the Cellulomonas genus.

• Korean Chemical Engineering Research
• /
• v.47 no.4
• /
• pp.410-417
• /
• 2009

Carbon dioxide was absorbed into GMA solution in a stirred flat cell using mesoporous catalyst Imidazole-CP-MS41, which was synthesized by CP-MCM41 with imidazole. Experiments were carried out at a batch-type absorber with different conditions, varying reaction temperature, concentration of GMA, solvent but maintaining 50 rpm of agitation speed and 2 g of catalyst. Absorption rate of $CO_2$ was used to obtain the kinetics based on the film theory using zwitterion mechanism with 2 elementary reaction and the kinetics were correlated with the solubility parameter of the solvents.

• Asian-Australasian Journal of Animal Sciences
• /
• v.25 no.10
• /
• pp.1404-1410
• /
• 2012

In vitro experiments were conducted to evaluate the suitability of several mixtures of high tanniniferous non legumes with low tanniniferous legumes on in vitro gas production (IVGP), dry matter degradation, Ammonia-N, methane production and microbial population. Eight treatments were examined in a randomized complete block design using four non-legumes and two legumes (Carallia integerrima${\times}$Leucaena leucocephala (LL) (Trt 1), C. integerrima${\times}$Gliricidia sepium (GS) (Trt 2), Aporosa lindeliyana${\times}$LL (Trt 3), A. lindeliyana${\times}$GS (Trt 4), Ceiba perntandra${\times}$LL (Trt 5), C. perntandra${\times}$GS (Trt 6), Artocarpus heterophyllus${\times}$LL (Trt 7), A. heterophyllus${\times}$GS (Trt 8). The condensed tannin (CT) content of non legumes ranged from 6.2% (Carallia integerrima) to 4.9% (Ceiba perntandra) while the CT of legumes were 1.58% (Leucaena leucocephala) and 0.78% (Gliricidia sepium). Forage mixtures contained more than 14% of crude protein (CP) while the CT content ranged from 2.8% to 4.0% respectively. Differences (p<0.05) were observed in in vitro gas production (IGVP) within treatments over a 48 h period dominated by C. perntandra${\times}$G. sepium (Trt 6). The net gas production (p<0.05) was also high with Trt6 followed by A. heterophyllus${\times}$L. leucocephala (Trt 7) and A. heterophyllus${\times}$G. sepium (Trt 8). Highest (p>0.05) NH3-N (ml/200 mg DM) production was observed with the A. heterophyllus${\times}$G. sepium (Trt 8) mixture which may be attributed with it's highest CP content. The correlation between IVGP and CT was 0.675 while IVGP and CP was 0.610. In vitro dry matter degradation (IVDMD) was highest in Trt 8 as well. Methane production ranged from 2.57 to 4.79 (ml/200 mg DM) to be synonimous with IVGP. A higher bacteria population (p<0.05) was found in C. perntandra${\times}$G. sepium (Trt 6) followed by Artocarpus heterophyllus+G. sepium (Trt 8) and the same trend was observed with the protozoa population as well. The results show that supplementing high tannin non leguminous forages by incremental substitution of legume forage increased gas production parameters, NH3-N, IVDMD and microbial population in the fermentation liquid. Methane production was not significantly affected by the presence of CT or different levels of CP in forage mixtures. Among non legumes, Ceiba perntandra and Artocarpus heterophyllus performed better in mixture with L. leucocephala and G. sepium.

• Journal of Food Hygiene and Safety
• /
• v.5 no.1
• /
• pp.27-34
• /
• 1990

As a link in the studies on the extracellular polysaccharide by lactic acid bacteria, the experiment was conducted to investigate the viscosity variations of 10% reconstituted skim milk and optimum cultural conditions for the production of extracellular polysaccharide. 1. The viscosity of 10% reconstituted skim milk cultured by 8tr. thermophilu8 510 reached 5,000 CP at $41^{\circ}C$ and on 5 days. Because it was the highest value among the microorganisms tested, Str. thermophilu8 510 was chosen as a main test microoganism and studied on factors affecting maximum viscosity depending upon production of exopolysaccharide. 2. Absorbance of synthetic culture medium was highest at $41^{\circ}C$. Sucrose, in a member of carbohydrates, was the most effective carbon source for the production of exopolysaccharide within 5% concentration. 3. The production of exopplysaccharide was stimulated by $Mg^{++}$.