• Journal of Korean Society of societal Security
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• v.4 no.2
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• pp.65-72
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• 2011

This study was carried out to investigate the cause of acidification of rainwater and to evaluate the possibility of alternative water resource in Saemangeum. The rainwater were collected in the kwangwhal-myun, Saemangeum from March to September, 2009. The collected 7 samples were analyzed with pH meter, IC (ion chromatography) and ICP (inductively coupled plasma) about the pH and the major ions ($SO{_4}^{2-}$, $NO_3{^-}$, $Cl^-$, $Ca^{2+}$, $K^+$, $NH^{4+}$, $Na^+$ and $Mg^{2+}$) of rainwater. The order of the major anion concentration and the acidification contribution in the rainwater was $SO{_4}^{2-}$>$NO_3{^-}$>$Cl^-$, and that of the major cation was $Ca^{2+}$>$K^+$>$NH_4{^+}$>$Na^+$>$Mg^{2+}$. In the initial rainwater, the major ions concentration were higher than the middle period. pH of the rainwater was the lowest at May, but similar to the results of the others. And pH of the rainwater were significant correlation with $SO{_4}^{2-}$ and $Cl^-$ in Saemangeum. From this results, the rainwater was slight acidic, and $SO{_4}^{2-}$ was the main factor contributed to the rainwater acidification in Saemangeum.

• Food Science of Animal Resources
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• v.22 no.3
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• pp.259-266
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• 2002

The egg shell membrane degrading isolated from soil was identified as Bacillus licheniformis by 16S rDNA identification method. A keratinase was isolated from the Baciilu licheniformis culture. DEAE-cellulose ion-exchange and Sephadex C-75 gel chromatograhies were used to purify the enzyme. The specific activity was increased 17.3-fold by the purification procedures. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis and Sephadex G-75 chromatography indicated that the purified keratinase was monomeric and had a molecular weight of 65 kDa. The enzyme showed optimum activity at pH 9.0, and was stable above pH 9.0. The optimum temperature was 50$\^{C}$ and the enzyme was stable in the temperature ranges from 20$\^{C}$ to 50t. By the addition of 1 mM and 10 mM FeSO4, the activities of the enzyme were increased to 111$\pm$4.6% and 133$\pm$3.79%, respectively. The keratinase was an alkaline serine pretense because it was inhibited only by phenylmethylsulfonylfluorice (PMSF).

• Korean Journal of Microbiology
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• v.41 no.1
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• pp.81-86
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• 2005

One of the endoglucanases, F-I-III, was purified from the culture filtrate of T. sp. C-4 through procedures including chromatography on Sephacryl S-200, DEAE-Sepharose A-50, and Chromatofocusing on Mono-P (FPLC). The molecular weight of the enzyme was determined to be about 56,000 Da by SDS-PAGE, and pI of 4.9 by analytical isoelectric focusing. F-I-III showed the highest enzyme activity at $55^{\circ}C$, and the pH optimum of the enzyme was 5.0. There was no loss of activity when the enzyme was incubated at $50^{\circ}C$ for 24 hours. The specific activity of the enzyme F-I-III toward the CMC was 315.4 U/mg. The Km value for $PNPG_2$ of F-I-III was 2.69 mM. N-terminal sequence of F-I-III was analyzed to be QPGTSTPEVHPKKLTTYK. It showed $95\%$ of homology to that of EGI from T. reesei. The presence of some metal ions (1 mM) had only a little effect on CMCase activity. The treatment of the reducing agents resulted in the increase of endoglucanase activity.

• Journal of Korean Society for Atmospheric Environment
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• v.21 no.4
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• pp.439-458
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• 2005

An automated analysis system for water soluble constituents in $PM_{2.5}$ has been developed. The system consists of a high capacity multi tube diffusion scrubber (MTDS), a low temperature particle impactor (LTPI), and two ion (anion and cation) chromatography (IC) systems. Atmospheric particles have been collected by passing sample air through a thermostated MTDS followed by a LTPI. This system allows simultaneous measurements of soluble ions in $PM_{2.5}$ at 30 minutes interval. At the air sampling flow rate of 1.0L/min, the detection limits of the overall system are in the order of tens of $ng/m^3$. This system has been successfully used for the measurement of particulate components of Seoul air from April 2003 to January 2004. $SO_4^{2-},\;NO_3^-,\;NH_4^+,\;NO_2^-,\;Cl^-,\;Na^+,\;K^+,\;Ca^{2+},\;and\;Mg^{2+}$ are the major ionic species for $PM_{2.5}$ at Seoul. Among them, $SO_4^{2-},\;NO_3^-\;and\;NH_4^+$ are the most abundant ions, contributed up to $86\%$ of the total and the concentrations were higher than those in any other urban sites in the world except for Chinese cities. There are high pollutant episodes which contribute about $15\~20\%$ of annual average values of the major ions. During the episode, the all parcels were transported from the asian continent and $PM_{2.5}$ were significantly neutralized. This suggests that aged and long range transported pollutants caused the high pollutant episodes. They showed a distinct daily and seasonal variations:they showed a peak in the early morning caused by the night-time accumulation of particulate matters. Atmospheric reactions including gas-to-particle reactions and inter-particle reactions and meteorological parameters including relative humidity and ambient temperature were described with related to the $PM_{2.5}$ 5 concentrations. All of the ionic species showed higher concentrations during the spring than those for summer and winter.

• Microbiology and Biotechnology Letters
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• v.15 no.2
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• pp.129-134
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• 1987

Aspergillus sp. (MK-24) producing a biological active substance that inhibited the venom proteinase activity was isolated from soil. The substance also inhibited the activity of trypsin and coagulation of blood, but did not inhibit papain, $\alpha$-chymotrypsin and pepsin. The substance was partially purified from culture filtrate by precipitaion with acetone, and by chromatography of DEAE-Sepadex A-50 column and Amberlite IRC-50 ion exchange. The inhibitory substance was stable in the wide pH range from 2.0 to 12.0 at 37$^{\circ}C$, but not stable at $65^{\circ}C$ in the alkaline pH. Only 12% of the activity was decreased by the heat treatment at 10$0^{\circ}C$ for two hours. The inhibition on venom proteinase (Agkistrodon bromohoffi brevicaudus) was a mixed type. The inhibitory activity depended on the preincubation time and completely depressed by cupric, zinc and cobalt ions. The inhibition on the venom proteinase was appeared strongly on casein but not on ovalbumin or hemoglobin as a substrate.

• Journal of the East Asian Society of Dietary Life
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• v.7 no.3
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• pp.289-300
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• 1997

Newborn dog chymosin was extracted from the stomachs of dogs of 2 weeks of age, and was purified by ion exchange chromatography. Half of the sequence was determined by amino acid sequencing and the complete sequence was deduced from a cloned chymosin cDNA Results showed that the zymogen showed 79% sequence identity with calf prochymosin and 54% identity with porcine pepsinogen A The size of the propart and location of the residue which becomes the amino-terminus in the active enzyme was the same in the prochymosins. The maximum general proteolytic activity at pH 3.2 of newborn dog chymosin was 3-4% of that of porcine pepsin A at pH 2, whereas the milk clotting activity relative to the general proteolytic activity of newborn dog chymosin was much higher than that of calf chymosin. Agar gel electrophoresis at pH 5.2 of stomach extracts of individual dogs showed the existence of two predominant genetic variants of zymogen and enzyme. The two variants could not be distinguished by amino acid composition or amino-terminal sequencing, and no differences in the enzymatic properties of the genetic variants were observed. It was concluded that of the residues that participate in the substrate binding, calf and newborn dog chymosin differ in the following positions (porcine pepsin numbering, subsites in parentheses) : Ser 12 Thr(S$_4$), Leu 30 Val(S$_1$/S$_3$), His 74 Gln(S'$_2$), Val 111 Ile(S$_1$/S$_3$), Lys 220 Met(S$_4$). With regard to the low general proteolytic activity of newborn dog chymosin, the substitution Asp303 Val relative to calf chymosin may contribute to an explanation of this.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.1
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• pp.97-100
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• 1992

The optimum condition for the extraction of antimicrobial substance from Lithospermi radix was investigated. For the purpose of obtaining basic data for the development of natural preservatives and for the prevention of food poisoning accidents, its antimicrobial activity was tested against several kinds of saprophytic microbes and food poisoning bacteria. The optimum condition for extraction of antimicrobial substance was to steep Lithospermi radix into 95% ethanol for 24 hours at room temperature. Antimicrobial activity was observed at the pH range $5.0{\sim}8.0$, but its activity became stronger at acidic condition. The result of ion exchange chromatography was showed that the antimicrobial activity of anionic portion was more apparent than that of cationic portion. The antimicrobial activity against Gram positive bacteria was stronger than that of Gram negative bacteria and the growth of food poisoning bacteria such as S. aureus and V. parahaemolyticus was inhibited in the concentration of 0.1% for 48 hours. As for mold and yeast, the growth of some kinds of these organisms was inhibited in the concentration of 0.1 % for 48 hours and the growth of nearly all the fungi was inhibited in the concentration of 0.15% for 96 hours.

• YAKHAK HOEJI
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• v.52 no.6
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• pp.419-425
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• 2008

A qualitative and quantitative analytical method was developed for detection of methamphetamine (MA) and its main metabolite amphetamine (AM) in oral fluid. Oral fluids of eleven drug abusers were provided by Police, specimens were collected by stimulation with a cotton swab treated with 20 mg of citric acid ($Salivette^{(R)}$; Sarstedt, USA). As the preliminary test, oral fluid samples were screened for amphetamines by Fluorescence Polarization Immunoassay (TDxFLx, Abbott Co.). Extraction for MA was performed using solid-phase extraction (SPE) by $RapidTrace^{TM}$ (Zymark, USA) with mixed mode cation exchange cartridge, CLEAN $SCREEN^{(R)}$ (130 mg/3 ml, UCT) after dilution with phosphate buffer. Samples were evaporated and derivatized by pentafluoropropionic acid anhydride (PFPA). Quantitation of MA and AM was performed by gas chromatography-mass spectrometry (GC-MS) using selective ion monitoring (SIM), the quantitation ions were m/z 204 (MA), 208 (MA-$D_5$), 190 (AM) and 194 (AM-$D_5$). The selectivity, linearity of calibration, limit of detection (LOD) and quantification (LOQ) within- and between day precision, accuracy and recoveries were examined as parts of the method validation. All oral fluid samples gave positive results to immunoassay for MA (cut-off level, 50 ng/ml as d-amphetamine). Concentrations of MA and AM by GC-MS in eleven samples were ranged 104.2${\sim}$4603.3 ng/ml and 32.4${\sim}$268.6 ng/ml, respectively. Extracted calibration curves of MA and AM were linear over the two concentration range of 1${\sim}$100 and 50${\sim}$1000 ng/ml with correlation coefficient of above 0.999. LOQ of MA and AM was 1 and 3 ng/ml, respectively. The intraand inter-day run precisions (CV) for MA and AM were less than 10%, and the accuracies (bias) for MA and AM were also less than 10% at the two different concentrations 5 and 100 ng/ml at low calibration range, 50 and 1000 ng/ml at high calibration range. The absolute recoveries of MA and AM at low and high calibration ranges were more than 82% and 75%, respectively. In this study the qualitative and quantitative analytical method of MA in oral fluid was established. Oral fluid testing may detect drug use in past hours because of its shorter detection window than urine, and be useful in post-accident situations. So oral fluids will be most useful for testing drug abuse in the driving under the influence of drug (DUID) as the alternative specimens of urine.

• Proceedings of the Botanical Society of Korea Conference
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• 1987.07a
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• pp.133-148
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• 1987

Gibberellin(GA) 3-$\beta$ hydroxylation is very important for the shoot elogation in the higher plants, since only 3$\beta$-hydryoxylated GAs promote shoot elogation in several plants. Fluctuation of 3$\beta$-hydryoxylase activity was examined during seed maturation using two cultivars of , P. vulgaris, Kentucky Wonder (normal) and Masterpiece (dwarf). Very immature seeds of both cultivars contain high level of 3$\beta$-hydroxylase activity (per mg protein). Both cultivars showed maximum of enzyme activity (per seed) in the middle of their maturation process. Gibberellin 3$\beta$-hydroxylase catalyzing the hydroxylation of GA20 to GA1 was purified 313-fold from very early immature seeds of P. vulgaris. Crude soluble enzyme extracts were purified by 15% methanol precipitation, hydrophobic interaction chromatogrphy, DEAE ion exchange column chromatography and gel filtration HPLC. The 3$\beta$-hydroxylase activity was unstable and lost much of its activity duting the purification. The molecular weight of purified enzyme was extimated to be 42, 000 by gel filtration HPLC and SDS-PAGE. The enzyme exhibited maximum activity at pH 7.7. The Km values for [2.3-3H] GA20 and [2.3-3H]GA9 were 0.29 $\mu$M and 0.33 $\mu$M, respectively. The enzyme requires 2-oxoglutarate as a cosubstrate; the Km value for 2-oxoglutarate was 250 $\mu$M using 3H GA20 as a substrate. Fe2+ and ascorbate significantly activated the enzyme at all purification steps, while catalase and BSA activated the purified enzyme only. The enzyme was inhibited by divalent cations Mn2+, Co2+, Ni2+, Cu2+, Zn2+, Cd2+ and Hg2+. Effects of several GAs and GA anaogues on the putrified 3$\beta$-hydroxylase were examined using [3H]GA9 and GA20 as a substrates. Among them, GA5, GA9, GA15, GA20 and GA44 inhibited the enzyme activity. [13C, 3H] GA20 was converted by the partially purified enzyme preparation to [13C, 3H]GA1, GA5 and GA6, which were identified by GC-MS, GA9 was converted only GA4, GA15 and GA44 were converted to GA37 and GA38, respectively. GA5 was epoxidized to GA6 by the preparation. This suggests that 3$\beta$-hydroxylation of GA20 and epoxidation of GA5 are catalyzed by the same enzyme in P, vulgaris.

• Food Science and Preservation
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• v.23 no.7
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• pp.1004-1011
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• 2016

Flavonoids, non-nutrient secondary metabolites of plants, are widely distributed in commonly consumed agro-food resources. Flavonoids include aglycones, and their glycosides are reported to have potential health-promoting compounds. The aim of this study was to investigate flavonoid glycosides in the fruit and leaves of Zizyphus jujuba var. inermis (Bunge) Rehder (jujube). A total of six flavonoids (five flavonols and one chalcone) were identified in jujube fruit and leaves by using ultra-performance liquid chromatography-diode array detector-quadrupole time of flight mass spectrometry along with chemical library and an internal standard. In positive ion mode, six flavonoids were linked to the C- and O-glycosides which were conjugated with sugar moieties based on kaempferol, quercetin, and phloretin aglycones. Total flavonoid contents of leaves (8,356.5 mg/100 g dry weight (DW)) was approximately 900-fold higher than that of fruit (fresh fruit, 13.6 mg/100 g dry DW; sun-dried fruits, 9.2 mg/100 g dry DW). Quercetin 3-O-rutinoside (rutin) and quercetin 3-O-robinobioside were the predominant flavonols in fruit and leaves of jujube. In particular, rutin had the highest content (6,735.2 mg/100 g DW) in leaves, and rutin is a widely reported bioactive compound. Phloretin 3',5'-di-C-glucoside (chalcone type) was detected only in leaves. The leaves of jujube contain a high content of flavonoids and the results of this study indicate that jujube leaves may be a source of bioactive flavonoids.