• Journal of Microbiology and Biotechnology
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• v.8 no.3
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• pp.251-257
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• 1998

Cycloinulooligosaccharide fructanotransferase (CFTase) which produces cyclofructan from inulin was purified 332-fold from a culture broth of Bacillus macerans CFCl. The molecular mass of the CFTase was estimated to be 110 kDa by SDS-polyacrylamide gel electrophoresis and gel filtration, indicating that the enzyme has a monomer structure. The maximal level of enzyme activity was observed at pH 7.5 and $45^{\circ}C$. The enzyme was stable in the pH range 6.0 to 9.5, and at temperatures up to $45^{\circ}C$ for 1 h. The enzyme activity was completely inhibited in the presence of 0.5 mM $Ag^+\;or\;Cu^2+$ ion. None of sucrose (GF), l-kestose (GF2), or nystose (GF3) were found to be substrates for the CFTase, but inulooligosaccharides larger than nystose were attacked by the enzyme. The CFTase catalyzes not only the cyclization as the major reaction, but also disproportionation and coupling reactions involving intermolecular transfructosylation in the same manner as cyclodextrin glucanotransferase (CGTase) (EC 2.4.1.19).

• The Korean Journal of Food And Nutrition
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• v.7 no.4
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• pp.259-266
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• 1994

The hyperthermophilic archaebacterium Thermococcus profundus Isolated from a deep-sea hydrothermal vent system, produced several amylolytic enzymes such as extracellular amylase and pullulanase, intracellular a-1,4-91ucosidase in respone to the presence of complex carbohydrates In the growth medium. This strain showed high activities on 0.5% maltose than on complex carbohydrates One of the amylases was partially purified by ammonium sulfate precipitation, DEAE-Toyopearl chromatography. The amylase exhibited maximal activity at pH 5.5 and 80$^{\circ}C$, and was stable in the range of pH 5.5 to 9.5 and up to 80$^{\circ}C$ for 30 min. The enzyme activity was no dependence on Ca2+ and not inhibited by detergents. The amylase hydrolyzed soluble starch, amylose, amylopectin and glycogen to produce maltose and maltotriose with trace amounts of glucose, but not pullulan and ${\alpha}$-, ${\beta}$-, ${\gamma}$-cyclodextrin. Malto-oligosaccharides ranging from maltotetraose to maltoheptaose were hydrolyzed in an endo fashion.

• Bulletin of the Korean Chemical Society
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• v.17 no.11
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• pp.1052-1056
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• 1996

The effects of β-CD, Me-β-CD, and biphenyl capped β-CD on 1H NMR spectra of mandelic acid 1, α-methylbenzylamine 2 and 2-phenylpropionic acid 3 were investigated. Enantiomeric recognition was observed for mandelic acid 1 by all the hosts used, for α-methylbenzylamine 2 by β-CD and Me-β-CD, and for 2-phenylpropionic acid 3 by Me-β-CD. In the presence of biphenyl-capped β-CD, ο-, m-, and p-protons of the phenyl groups of the guests are discriminated due to ring current of the capped biphenyl group. The splitting pattern of the phenyl protons indicates that the phenyl group of the guests is inserted into the β-CD cavity from the secondary hydroxyl side and positioned in close proximity to the capped biphenyl ring. The magnitude of the upfield shifts of H3 and H5 protons of β-CD upon binding of guests 1-3 is similar to that caused by ephedrine or pseudoephedrine, suggesting that the substitution at benzylic carbon atom has little effect on the depth of the insertion of the phenyl group into the β-CD cavity and stability of the inclusion complexes.

• Analytical Science and Technology
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• v.19 no.4
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• pp.275-279
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• 2006

A capillary electrophoresis method for the separation of carvedilol and its metabolites enantiomers using cyclodextrins as the chiral selectors was developed. The effect of several types of cyclodextrins, concentration and capillary temperature for enantiomer resolution were investigated. Best results were obtained by 15 mM carboxymethyl-${\beta}$-cyclodextrin in the run buffer. Also the effect of capillary temperature on efficiency was assessed. The optimized method was applied for separation of chiral carvedilol and its three metabolites.

• Journal of KIISE:Databases
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• v.31 no.5
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• pp.468-478
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• 2004

It is essential in various application areas of data mining and bioinformatics to effectively retrieve the occurrences of interesting patterns from sequence databases. For example, let's consider a network event management system that records the types and timestamp values of events occurred in a specific network component(ex. router). The typical query to find out the temporal casual relationships among the network events is as fellows: 'Find all occurrences of CiscoDCDLinkUp that are fellowed by MLMStatusUP that are subsequently followed by TCPConnectionClose, under the constraint that the interval between the first two events is not larger than 20 seconds, and the interval between the first and third events is not larger than 40 secondsTCPConnectionClose. This paper proposes an indexing method that enables to efficiently answer such a query. Unlike the previous methods that rely on inefficient sequential scan methods or data structures not easily supported by DBMSs, the proposed method uses a multi-dimensional spatial index, which is proven to be efficient both in storage and search, to find the answers quickly without false dismissals. Given a sliding window W, the input to a multi-dimensional spatial index is a n-dimensional vector whose i-th element is the interval between the first event of W and the first occurrence of the event type Ei in W. Here, n is the number of event types that can be occurred in the system of interest. The problem of‘dimensionality curse’may happen when n is large. Therefore, we use the dimension selection or event type grouping to avoid this problem. The experimental results reveal that our proposed technique can be a few orders of magnitude faster than the sequential scan and ISO-Depth index methods.hods.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.4
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• pp.614-620
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• 2004

This study was to determine the effect of dietary $\beta$-cyclodextrin ($\beta$CD) on egg quality and cholesterol content of egg yolk. One-hundred 28-week-old laying hens were randomly distributed into five groups of twenty hens each and maintained in individual laying cages for 10 weeks of the experiment. They were assigned to the five treatments of experimental layer diets containing 0, 3, 5, 7 or 10% pure $\beta$CD of diets. Food intake, egg production and egg weight varied slightly and insignificantly in the hens fed with 0, 3, 5 or 7% $\beta$CD-added diets. But food intake, egg production, and egg weight were uniformly lower (p＜0.05) in the hens fed with 10% $\beta$CD-added diets. Food conversion rate, when expressed per number egg, was impaired (p＜0.05) without having an obvious relation to the dietary $\beta$CD level. No difference in haugh unit, egg yolk color, and egg shell thickness was found among treatment. The cholesterol content of egg yolks was significantly decreased (p＜0.05) to 3.76, 5.12, 5.49 and 6.48 mg/g yolk in $\beta$CD 3, 5, 7 and 10% treatments respectively when compared to that of the $\beta$CD 0% group. The cholesterol content of eggs, when expressed in mg/60 g egg, was greatly (p＜0.05) decreased to 54, 71, 77 and 86 mg in $\beta$CD 3, 5, 7 and 10% treatments when compared to that of the $\beta$CD 0% group. The most striking effects (p＜0.05) were observed in $\beta$CD 5% and 7% treatments, whose cholesterol content decreased from 28.19% to 30.23%. In conclusion, $\beta$CD added-diets fed to laying hens can reduced the cholesterol content of egg yolk, and this new type of egg yolk with lower cholesterol can be considered a functional livestock food.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.2
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• pp.193-201
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• 2000

Partitioning of hydrophobic organic compounds (HOCs) to a biosurfactant, hydroxypropyl-${\beta}$-cyclodextrin (HPCD), was conducted to evaluate the feasibility of using HPCD to remove HOCs from soil/groundwater. HOC partitioning to HPCD was very fast, with over 95% of the complexation occurring within 10 min. Some influence of solution chemistry and HOC concentration on HOC-HPCD complex formation coefficients was observed. HPCD sorption on soil as quantified by both a fluorescence technique and total organic carbon measurements was negligible, indicating no significant affinity of HPCD for the solid phase. Although the HOC solubilization capability of HPCD was lower than that of synthetic surfactants such as SDS and Tween 80, HPCD can be effective in removing sorbed HOCs from a model subsurface environment, primarily because of its negligible sorption to the solid phase (i.e., all the HPCD added facilitates HOC elution). However, in contrast with conventional surfactants, HPCD becomes relatively less effective for HOC partitioning with increasing HOC size and hydrophobicity. Therefore, comparisons between HPCD and synthetic surfactants for enhanced remediation applications must consider the specific HOC(s) present and the potential for surfactant material losses to the solid phase, as well as other more generally recognized considerations such as material costs and potential toxicological effects.

• Bulletin of the Korean Chemical Society
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• v.30 no.9
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• pp.2021-2026
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• 2009

Toluene, xylene and styrene are volatile organic solvents that are commonly used in mixtures in many industries. Because these solvents are metabolized and then excreted in urine, their urinary metabolites are thought to be biomarkers of occupational exposure to these solvents. Therefore, a simple, rapid, and yet reliable analytical method for determining the metabolites is required for accurate biological monitoring. In the present study, a simple and rapid HPLC-UV method was developed for the simultaneous determination of eight major metabolites of toluene, xylene and styrene: hippuric acid (HA), mandelic acid (MA), o-, m- and p-methylhippuric acids (o-, m- and p-MHAs), and o-, m- and p-cresols. A monolithic column was employed as the stationary phase and several conditions, including flow rate, composition of mobile phase and column temperature, were variables for the optimization of the chromatographic resolution. All eight metabolites were successfully resolved within 5 minutes in 10% aqueous ethanol containing 0.3% acetic acid and 1.6% $\beta$-cyclodextrin, using a flow rate gradient of 1.0 - 5.0 mL/min at 25 ${^{\circ}C}$. The performance of this method was validated by linearity, intra- and inter-day accuracy, and precision. The linearity was observed with correlation coefficients of 0.9998 for HA, 0.9999 for MA, 0.9989 for o-MHA, 0.9998 for m-MHA, 0.9991 for p-MHA, 0.9997 for o-cresol, 0.9998 for m-cresol, and 0.9986 for p-cresol. The intra- and inter-day precision of the method were less than 5.89% (CV) and the accuracy ranged from 92.95 to 106.62%. The validity was further confirmed by analysis of reference samples that were prepared by the inter-laboratory quality assurance program of the Korea Occupational Safety and Health Agency (KOSHA, Seoul, Korea). All measured concentrations of the analytes agreed with the certified values.

• Journal of the Korean GEO-environmental Society
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• v.15 no.12
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• pp.61-69
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• 2014

Carboxymethyl-${\beta}$-cyclodextrin (${\beta}$-CMCD), as a biodegradable surfactant with hydrophobic and hydrophilic properties, has potential advantages of being applicable to the simultaneous treatment of multiple contaminated soils. In this study, the desorption behaviors of r adionuclides such as cobalt (Co), strontium (Sr), and cesium (Cs) from the soil contaminated with them were experimentally investigated and the effectiveness of CMCD as a desorbent was evaluated. The desorption equilibrium of used radionuclides could be achieved within 1~3 hr and the desorption ratio from kaolin was higher than that from natural soil. The addition of CMCD of 2 g/L increased the desorption ratio by 5~20 % and the desorption ratio of used r adionuclides was shown in the order of Co > Cs > Sr. The experimental desorption data were fitted successfully by pseudo-second order kinetic model and the desorption rate of the r adionuclides was shown in the order of Cs > Co > Sr. Hysteresis between adsorption and desorption of the r adionuclides, as shown in the order of Sr > Co > Cs, increased as the desorption rate decreased. Consequently, it could be considered that the desorption rate was one of the significant factors of the hysteresis. The addition of CMCD as desorbent increased the amount of desorbed radionuclides and decreased the hysteresis. However, the CMCD could not completely desorb the radionuclides from soils even though the excess of CMCD was added.

• Korean Journal of Food Science and Technology
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• v.41 no.6
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• pp.657-661
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• 2009

Liquid microparticulated seaweed calcium was manufactured via a wet grinding process. Thereafter, different forming agents such as cyclodextrin, gum arabic, and Na-caseinate were added to the liquid calcium, which was then spray-dried to investigate the quality of the powdered calcium treatments. The moisture contents of samples were approximately 2%. It was also determined that the different kinds of forming agents did not affect the spray drying efficiency. In addition, calcium solubility was the highest in a solution of pH 2. In buffer solution and vinegar, the powdered calcium made with gum arabic showed the highest solubility among the treatments. The calcium contents of all the powdered microparticulate seaweed calcium samples were about 28%, and calcium content was not affected by the forming agents. The spray-dried calcium powder made by spray drying with gum arabic had the highest water vapor uptake, whereas the seaweed calcium was stable in terms of water adsorption. The results of SEM observations indicated that a portion of the spray-dried calcium powders were in nano-scale after wet-grinding. Among the treatments, the use of saccharides as a forming agent resulted in the most uniform particle distribution after spray-drying.