• Journal of Microbiology and Biotechnology
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• v.12 no.3
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• pp.470-475
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• 2002

In the course of screening for a novel cell cycle inhibitor, a potent Cdk 1 inhibitor, HY558, was found from the culture broth of Penicillium minioluteum F558 isolated from a soil sample. The molecular ion of HY558 was identified at m/z 329 (MH+) with a molecular formula of $C_20H_44ON_2$. HY558 exhibited selective antiproliferative effects on various human cancer cell lines. Its $IC_50$ values were estimated to be 0.29 mM on HepG2, 0.30 mM on HeLa, 0.30 mM on HL6O, 0.33 mM on HT-29, and 0.25 mM on AGS cells. Interestingly, Hy558 demonstrated no antiproliferative effect with normal lymphocytes used as the control, and a low level of inhibition on the proliferation of A549 cancer cells. A flow cytometric analysis of HepG2 cells revealed an appreciable arrest of cells at the G1 and G2/M phases of the cell cycle following treatment with Hy558. furthermore, DNA fragmentation due to apoptosis was observed in HeLa cells treated with 0.46 mM of HY558.

• JSTS:Journal of Semiconductor Technology and Science
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• v.17 no.1
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• pp.141-146
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• 2017

In this letter, we propose the use of tunneling field effect transistors (TFET) as a biosensor that detects bio-molecules on the gate oxide. In TFET sensors, the charges of target molecules accumulated at the surface of the gate oxide bend the energy band of p-i-n structure and thus tunneling current varies with the band bending. Sensing parameters of TFET sensors such as threshold voltage ($V_t$) shift and on-current ($I_D$) change are extracted as a function of the charge variation. As a result, it is found that the performances of TFET sensors can surpass those of conventional FET (cFET) based sensors in terms of sensitivity. Furthermore, it is verified that the simultaneous sensing of two different target molecules in a TFET sensor can be performed by using the ambipolar behavior of TFET sensors. Consequently, it is revealed that two different molecules can be sensed simultaneously in a read-out circuit since the multi-sensing is carried out at equivalent current level by the ambipolar behavior.

• Preventive Nutrition and Food Science
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• v.11 no.1
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• pp.67-72
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• 2006

To determine the amount of phytate in rice grains from various cultivars, two methods were employed and compared in respect of the accuracy and conveniency. Phytate in rice samples was extracted with HCl, and then the extracts were subjected to an anion-exchange column. Finally, the phytate in eluate was quantitated using two methods: one method is based on the complex formation between ferric ion and sulfosalicylic acid in the presence of phytate, and the other is the prior acid digestion of phytate sample, followed by the colorimetric determination of liberated phosphorus. Although two methods showed similar values of phytate in rice samples, the former method is simpler and more precise than the latter. Moreover, the former is more reliable for the samples with lower phytate levels. Especially, the dilution condition of rice sample before anion exchange column separation was important for the recovery of phytate in rice samples. Based on the former method, the amount of phytate in rice of various cultivars was estimated to range from 7.3 mg/g to 12.4 mg/g rice. This method would be useful for the determination of phytate in crop samples with a lower level of phytate, one of anti-nutrients in some agricultural plants.

• Journal of Environmental Science International
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• v.26 no.8
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• pp.903-911
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• 2017

The purpose of this study was to measure the bioactivity and antioxidant activity of peel from Gardenia jasminoides fructus Ellis (GJE) in Namhae, Korea, following some established methods. CM (Chloroform:Methanol, 2:1, v/v), 70% ethanol, and n-butanol extracts were collected. Flavonoid content and value as a functional food ingredient of GJE peel was investigated through assessing antioxidant [DPPH (1,1'-diphenyl-2-picrylhydrazyl), ABTS (2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid)], and hydroxyl radical scavenging activities; superoxide dismutase like ability; ferrous ion-chelating capacity; and tannin content by solvent extraction. Solvent extract antioxidant activities significantly increased (p<0.05) at increasing concentrations (0.2, 0.4, 0.6 mg/mL). GJE peel extracts were less active than the positive control [ascorbic acid, BHA (butylated hydroxyanisole), and EDTA (ethylenediaminetetraacetic acid disodium salt dihydrate)]. Based on the results of this study, GJE peel could be used as a natural antioxidant source due to its high antioxidant activity and bioactive compound content.

• Korean Journal of Materials Research
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• v.28 no.1
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• pp.68-74
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• 2018

Cobalt-incorporated zeolitic imidazolate framework ZIF-8 was synthesized by a simple one-pot synthesis method at room temperature. Powder X-ray diffraction patterns and energy dispersive X-ray spectrum confirmed the formation of the bimetallic Co/Zn-ZIF structure. UV-Vis diffuse reflectance spectra revealed that the bimetallic ZIF had a lower HOMO-LUMO gap compared with ZIF-8 due to the charge transfer process from organic ligands to cobalt centers. A hydrolytic stability test showed that Co/Zn-ZIF is very robust in aqueous solution - the most important criterion for any material to be applied in photodegradation. The photocatalytic efficiency of the synthesized samples was investigated over the Indigo Carmine (IC) dye degradation under solar simulated irradiation. Cobalt incorporated ZIF-8 exhibited high efficiency over a wide range of pH and initial concentration. The degradation followed through three distinct stages: a slow initial stage, followed by an accelerated stage and completed with a decelerated stage. Moreover, the photocatalytic performance of the synthesized samples was highly improved in alkaline environment rather than in acidic or neutral environments, which may have been because in high pH medium, the increased concentration of hydroxyl ion facilitated the formation of hydroxyl radicals, a reactive species responsible for the breaking of the Indigo Carmine structure. Thus, Co/Zn-ZIF is a promising and green material for solving the environmental pollution caused by textile industries.

• Preventive Nutrition and Food Science
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• v.10 no.3
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• pp.279-284
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• 2005

Uncoupling protein-1 (UCP-1) plays a major role in thermogenesis, and has been implicated in the pathogenesis of obesity and metabolic disorders. The aim of this study was to estimate the effects of A-3826G polymorphism of UCP-1 gene on body fat distribution. Two hundred forty eight Korean female overweight subjects with BMI more than 25 kgfm2 participated in this study. The areas of abdominal subcutaneous and visceral fat of all subjects were measured from computed tomography cross sectional pictures of the umbilical region. Subcutaneous fat areas of upper and lower thigh were also measured. Body composition was measured by bio-impedance analysis, and serum concentrations of biochemical parameters, such as glucose, triglyceride, cholesterol etc, were also measured. Genotype of UCP-1 was analyzed by polymerase chain reaction (PCR) restriction fragment length polymorphism (RFLP) method. The frequencies of UCP-1 genotypes were AA type; $27.8\%,\;AG\;type;\;51.2\%\;and\;GG\;type;\;21.0\%,$ and the frequency of G allele was 0.47. Body weight, BMI, WHR, SBP, DBP and body compositions were not significantly different by UCP-1 genotype. Abdominal visceral fat area was significantly higher in AG and GG type compared with AA type (p=0.009), but subcutaneous fat areas were not significantly different by UCP-1 genotype. Among biochemical parameters, LDL cholesterol level was significantly higher in GG type compared with AA and AG types (p=0.033). Among all subjects, 121 subjects finished 1 month weight loss program containing hypocaloric diet and exercise. The reduction of body weight and BMI were lower in GG type compared with AA/AG type even though statistical significances were not found (p > 0.05). These results suggest that UCP-1 genotype has a significant effect on visceral fat accumulation among Korean female overweight subjects with BMI more than $25\;kg/m^2$.

• Journal of Microbiology and Biotechnology
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• v.22 no.1
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• pp.58-68
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• 2012

An investigation was conducted on the enhancement of production and purification of an oxidant and SDS-stable alkaline protease (BHAP) secreted by an alkalophilic Bacillus horikoshii, which was screened from the body fluid of a unique Korean polychaeta (Periserrula leucophryna) living in the tidal mud flats of Kwangwha Island in the Korean West Sea. A prominent effect on BHAP production was obtained by adding 2% maltose, 1% sodium citrate, 0.8% NaCl, and 0.6% sodium carbonate to the culturing medium. The optimal medium for BHAP production contained (g/l) SBM, 15; casein, 10; $K_2HPO_4$, 2; $KH_2PO_4$, 2; maltose, 20; sodium citrate, 10; $MgSO_4$, 0.06; NaCl, 8; and $Na_2CO_3$, 6. A protease yield of approximately 56,000 U/ml was achieved using the optimized medium, which is an increase of approximately 5.5-fold compared with the previous optimization (10,050 U/ml). The BHAP was homogenously purified 34-fold with an overall recovery of 34% and a specific activity of 223,090 U/mg protein using adsorption with Diaion HPA75, hydrophobic interaction chromatography (HIC) on Phenyl-Sepharose, and ion-exchange chromatography on a DEAE- and CM-Sepharose column. The purified BHAP was determined a homogeneous by SDS-PAGE, with an apparent molecular mass of 28 kDa, and it showed extreme stability towards organic solvents, SDS, and oxidizing agents. The $K_m$ and $k_{cat}$ values were 78.7 ${\mu}M$ and $217.4s^{-1}$ for N-succinyl-Ala-Ala-Pro-Phe-pNA at $37^{\circ}C$ and pH 9, respectively. The inhibition profile exhibited by PMSF suggested that the protease from B. horikoshii belongs to the family of serine proteases. The BHAP, which showed high stability against SDS and $H_2O_2$, has significance for industrial application, such as additives in detergent and feed industries.

• Journal of the Korean Society of Radiology
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• v.11 no.3
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• pp.147-151
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• 2017

Potentially lethal damage repair (PLDR) in HFL-I was investigated by delayed plating experiments. The surviving fraction data were fitted to the linear Quadratic equation ($LogSn=-n{\gamma}({\alpha}d+{\beta}d^2$) where ${\gamma}=1$ for immediate plating). And a repair factor ${\gamma}$ was developed to compare survival for immediate and delayed plating. When we only took into account the repair factor of PLDR ${\gamma}$ which was derived from the delay assay, the cell survival response th fractionated carbon ion irradiation was not fully matched. This gap suggested that consideration of another repair process is necessary. So this suggests that the various repair process plays an important role in the fractionated irradiations.

• Korean Journal of Food Science and Technology
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• v.25 no.5
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• pp.576-581
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• 1993

Polygalacturonase(PG) was extracted from Chinese cabbage and partially purified by ammonium sulfate fractionation and ion-exchange chromatography. Three fractions, D-PG, C-1 PG, and C-2 PG, were separated by CM-Sephadex C-25 column chromatography and FPLC Mono Q HR 5/5 or Mono S HR 5/5 column and their physicochemical characteristics were investigated. All three fractions had optimum pH and temperature of 4.5 and $65^{\circ}C$, and were stable in the range of pH $4.5{\sim}8.0$. These fractions were inhibited by 0.8mM $CaCl_2$ or 0.6M NaCl. In the thermal inactivation of PC isozymes at $65{\sim}80^{\circ}C$, z-values were $8.4{\sim}9.3^{\circ}C$ and D-values at $80^{\circ}C$ were In the range of $120{\sim}126s$. Thermodynamic constants were calculated from thermal inactivation data of the isozymes and were applicable to estimation of thermal process time of retort pouched Kimchi.

• Korean journal of food and cookery science
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• v.26 no.3
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• pp.246-251
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• 2010

This study was conducted to investigate the quality characteristics of guavapyun after the addition of different ratios of extract (0.25, 0.5, 0.75, 1.0%), non-extract and vitamin C. The quality if the pyun containing 0.5% of the guava fruit extract (guavapyun) and vitamin C was higher compared with the quality of the control pyun. In the results of the proximatecomposition, the content of water was high in the control pyun relative to the vitamin C pyun and guavapyun and the carbohydrate, ash, crude lipid and protein content was high in guavapyun. The sweetness, pH and color (L, a, b value) were very high in the samples. The texture, hardness, chewiness and gumminess were significantly high in the control pyun and the adhesiveness and cohesiveness were high in guavapyun. However, there were no significant differences in springiness between the control and the added samples. The total phenolic content was higher in guavapyun (23.57 mg GAE/100 g) than the control pyun (18 mg GAE/100 g) and vitamin C pyun(15.05 mg GAE/100 g). The antioxidant activities determined by the DPPH method and ABTS method was higher in guavapyun (41.37 mM TE/g, 15.35 mM TE/g) than the control pyun (4.43 mM TE/g, 2.17mM TE/g) and vitamin C pyun (11.33 mM TE/g, 4.51 mM TE/g). Using the FRAP method, guavapyun(9.06 mM TE/g) was shown to exhibit a stronger ferrous ion chelating activity than the control pyun (4.49mM TE/g) and vitamin C pyun (7.03 mM TE/g). Thus, the studied indigenous guavapyun was high in both antioxidative activity and total phenolic content.