• Microbiology and Biotechnology Letters
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• v.49 no.1
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• pp.45-56
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• 2021

Improved amylases were developed from protoplast fusants of two amylase-producing Aspergillus species. Twenty regenerated fusants were screened for amylase production using Remazol Brilliant Blue agar. Crude enzyme extracts produced by solid state fermentation of rice bran were assayed for activity. Three variable factors (temperature, pH and enzyme type) were optimized to increase the amylase activity of the parents and selected fusants using rice bran medium and solid state fermentation. Analysis of this optimization was completed using the Central Composite Design (CCD) of the Response Surface Methodology (RSM). Amylase activity assays conducted at room temperature and 80℃ demonstrated that Aspergillus designates, T5 (920.21 U/ml, 966.67 U/ml), T13 (430 U/ml, 1011.11 U/ml) and T14 (500.63 U/ml, 1012.00 U/ml) all exhibited improved function making them the preferred fusants. Amylases produced from these fusants were observed to be active over the entire pH range evaluated in this study. Fusants T5 and T14 demonstrated optimal activity under acidic and alkaline conditions, respectively. Fusants T13 and T14 produced the most amylase at 72 h while parents TA, TC and fusant T5 produced the most amylase after 96 h of incubation. Response surface methodology examinations revealed that the enzyme from fusant T5 was the optimal enzyme demonstrating the highest activity (1055.17 U/ml) at pH 4 and a temperature of 40℃. This enzyme lost activity with further increases in temperature. Starch hydrolysis using fusant T5 gave the highest yield of glucose (1.6158 g/100 ml). The significant activities of the selected fusants at 28 ± 2℃ and 80℃ and the higher sugar yields from cassava starch hydrolysis over their parental strains indicate that it is possible to improve amylase activity using the protoplast fusion technique.

• Journal of Microbiology and Biotechnology
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• v.20 no.3
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• pp.518-524
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• 2010

A mannanase gene (man26B) was obtained from a sea bacterium, Paenibacillus sp. BME-14, through the constructed genomic library and inverse PCR. The gene of man26B had an open reading frame of 1,428 bp that encoded a peptide of 475- amino acid residues with a calculated molecular mass of 53 kDa. Man26B possessed two domains, a carbohydrate binding module (CBM) belonging to family 6 and a family 26 catalytic domain (CD) of glycosyl hydrolases, which showed the highest homology to Cel44C of P. polymyxa (60% identity). The optimum pH and temperature for enzymatic activity of Man26B were 4.5 and $60^{\circ}C$, respectively. The activity of Man26B was not affected by $Mg^{2+}$ and $Co^{2+}$, but was inhibited by $Hg^{2+},\;Ca^{2+},\;Cu^{2+},\;Mn^{2+},\;K^+,\;Na^+$, and $\beta$-mercaptoethanol, and slightly enhanced by $Pb^{2+}$ and $Zn^{2+}$. EDTA did not affect the activity of Man26B, which indicates that it does not require divalent ions to function. Man26B showed a high specific activity for LBG and konjac glucomannan, with $K_m,\;V_{max}$, and $k_{cat}$ values of 3.80 mg/ml, 91.70 ${\mu}mol$/min/mg protein, and 77.08/s, respectively, being observed when LBG was the substrate. Furthermore, deletion of the CBM6 domain increased the enzyme stability while enabling it to retain 80% and 60% of its initial activity after treatment at $80^{\circ}C$ and $90^{\circ}C$ for 30 min, respectively. This finding will be useful in industrial applications of Man26B, because of the harsh circumstances associated with such processes.

• Bulletin of the Korean Chemical Society
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• v.25 no.7
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• pp.1078-1080
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• 2004

• Bulletin of the Korean Chemical Society
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• v.35 no.7
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• pp.2019-2024
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• 2014

NiCu alloys have been suggested as potential candidates for catalysts in glucose oxidation. In this study, NiCu alloys with different compositions were prepared on a glassy carbon substrate by changing the electrodeposition potential to examine the effect of Ni/Cu ratios in alloys on catalytic activity toward glucose oxidation. Cyclic voltammetry and chronoamperometry showed that NiCu alloys had higher catalytic activity than pure Ni and Cu catalysts. Especially, Ni59Cu41 had superior catalytic activity, which was about twice that of Ni at a given oxidation potential. X-ray analyses showed that the oxidation state of Ni in NiCu alloys was increased with the content of Cu by lattice expansion. Ni components in alloys with higher oxidation state were more effective in the oxidation of glucose.

• Journal of Microbiology
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• v.44 no.3
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• pp.276-283
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• 2006

The thermophilic fungus Thermoascus aurantiacus 179-5 produced large quantities of a glucosidase which preferentially hydrolyzed maltose over starch. Enzyme production was high in submerged fermentation, with a maximal activity of 30 U/ml after 336 h of fermentation. In solid-state fermentation, the activity of the enzyme was 22 U/ml at 144 h in medium containing wheat bran and 5.8 U/ml at 48 h when cassava pulp was used as the culture medium. The enzyme was specific for maltose, very slowly hydrolyzed starch, dextrins (2-7G) and the synthetic substrate (${\alpha}$-PNPG), and did not hydrolyze sucrose. These properties suggest that the enzyme is a type II ${\alpha}$-glucosidase. The optimum temperature of the enzyme was $70^{\circ}C$. In addition, the enzyme was highly thermostable (100% stability for 10 h at $60^{\circ}C$ and a half-life of 15 min at $80^{\circ}C$), and stable within a wide pH range.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.9
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• pp.1286-1293
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• 2014

Typically, studies through the simulation system have been progressed, because the evaluation of the driver's arousal state about the service of a actual train has risk of safety for the driver. When configured event same as the real in simulation system, the ability to cope with an accident situation may be the same each other. But the difference in the state of tension or arousal will occur. In this study, requested to cooperate with the railways in order to escape from these constraints, and the target of the experiment was to real engineer service. I was set about experiment when the train was stopped as safe as possible. As a result, the beta wave of EEG signals that representing complex calculations or anxiety is increased rapidly on the basis of a flag station from at the time of departure. The size of the electrodermal activity signal in response to movement of the body gave a noticeable. In terms of HRV, if the train approach a flag station gradually and the R-R interval is narrowed. So that the driver can be estimated as arousal state. In accordance with this study, if the quantitative standard of arousal state be based on the driver's biosignals will provide, it will be able to take advantage of development the system that would prevent train accidents caused by human error.

• Journal of environmental and Sanitary engineering
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• v.22 no.1 s.63
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• pp.57-66
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• 2007

Changes in the alliinase activity during the hot air drying and vacuum freeze drying of garlic samples treated as the whole, sliced and crushed state were investigated. The specific activity of alliinase in raw garlic was 8.52 units/mg protein. The activity in the whole garlic prepared by the hot air drying for 8 hrs was reduced remarkably to 5.22 units/mg protein with 61% remaining and to 4.25 units/mg protein with 50% remaining for 36 hrs. The activity in the sliced garlic prepared by the hot air drying for 36 hrs was reduced to 3.55 units/mg protein with 42% remaining and the activity in the crushed garlic prepared by the hot air drying for 36 hrs was reduced to 3.12 units/mg protein with 37% remaining. The garlic sample sliced or crushed was higher than the whole state in the efficiency of drying but was lower in the remaining activity of alliinase. The activity in the whole garlic prepared by the vacuum freeze drying for 8 hrs was reduced to 7.21 units/mg protein with 85% remaining and to 5.53 units/mg protein with 65% remaining for 36 hrs. The activity in the sliced garlic prepared by the vacuum freeze drying for 36 hrs was reduced to 4.55 units/mg protein with 53% remaining and the activity in the crushed garlic prepared by the vacuum freeze drying for 36 hrs was reduced to 4.16 units/mg protein with 49% remaining. The remaining activity of alliinase in the garlic samples prepared by the vacuum freeze drying was higher than the remaining activity in the garlic samples prepared by the hot air drying.

• Journal of Microbiology and Biotechnology
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• v.11 no.6
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• pp.951-956
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• 2001

A 28-kDa extracellular lipase (pI 8.7) was purified to homogeneity from the culture supernatant of Trichosporon sp. Y- 11 by mmonium sulfate precipitation, DEAE-Sephadex A-50, Bio-Gel P-30, CM- Sephadex C-50, and Bio-Gel P- 10 chromatographies. The purified enzyme exhibited a specific activity of $2,741{\;}{\mu}mol/min/mg$ based on the hydrolysis of triolein, and the optimal hydrolysis activity was dentified at pH 8.0 and $40^{\circ}C$. The enzyme activity was inhibited by $Ag^+$ and enhanced by $Fe^{2+}$, $Fe^{3+}$, $Mg^{2+}$, $Mn^{2+}$, and $Li^{+}$. The enzyme activity exhibited for the hydrolysis of both tributyrin and trilinolein. The ester synthesis of unsaturated fatty acids with various alcohols catalyzed by the purified lipase in a nonaqueous medium or microaqueous system was also investigated. The esterification activity of the lipase increased with an increase of the carbon chain length in the alcohol. The synthesis rate of linoleic acid and oleyl alcohol was the highest with an optimal temperature and pH of $40^{\circ}C$ and 8.0, respectively. The water content and agitation also affected the esterification activity of the lipase.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.51 no.1
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• pp.32-38
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• 2002

This paper describes a development of a portable physical activity monitoring system using two accelerometers to quantify physical activity. The system hardware consists of two piezoresistive accelerometers, amplifiers with gain of 30, lowpass filters with cut-off frequency of 15Hz, offset control circuits, one-chip microcontroller and flash memory card. In order to evaluate the performance of the system we acquired 3 channel data at 32 sample/sec from body-fixed accelerometers in chest and right upper leg. And then the acquired data were processed by MatLab on personal computer. We tried to distinguish not only fundamental actions which are steady-state activities such as standing, sitting, and lying but also dynamic activities with walking, up a stairway, down a stairway, and running. Five subjects participated the evaluation process which compare the video data with the measured data. As a result, the activity classification rate of 90.6% on average was obtained. Overall results showed that the steady-state activities could be classified from the low component of 3-axis acceleration signal and dynamic activities could be distinguished from frequency analysis using wavelet transform and FFT. Finally, we could find that this system can be applied to acquire and analyze the static and dynamic physical activity data.

• Journal of Korean Physical Therapy Science
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• v.29 no.1
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• pp.55-63
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• 2022

Background: This study investigated the effect of erector spinae and quadratus lumbar kinesio taping and support surface conditions on abdominal muscle activity during plank exercise. Design: Within-Group design. Methods: A total of twenty-three healthy men and women participated in this study. Abdominal muscle (both external obliques and internal oblique muscle) contraction was analyzed through EMG measurement with the presence or absence of kinesio taping applied to the erector spinae muscle and quadratus lumborum muscle during plank exercise and the difference between the support surfaces (stable surface and unstable surface) as variables. Abdominal EMG was attached to the right external oblique, left external oblique, right internal oblique, and left internal oblique. Results: The results showed that Abdominal left and right external obliques and internal obliques showed significant increases in activity when kinesio taping was applied to the erector spinae and quadratus lumborum muscles and unstable ground (p<0.05). Conclusion: In this study, we confirmed that the activity of the abdominal muscles was significantly increased during the plank operation in the state where the kinesio tape was attached. In addition, it was confirmed that the activity of the abdominal muscles was significantly increased during the plank operation on the unstable surface. These results suggest that in the state of kinesio tape attached and instability, plank motion has a positive effect on abdominal muscle activity.