• Journal of Biomedical Engineering Research
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• v.34 no.2
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• pp.63-68
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• 2013

Activeness of exercise is critical for stroke rehabilitation so that application of stimulation in response to patient's intention would be effective in FES cycling. The purpose of this study was to investigate the relationship between muscle reaction force (MRF) and electromyogram (EMG) during cycling exercise, for the future usage of MRF as patients' intention signal. Seven young men ($24{\pm}1.63$ yrs) participated in this study. Cycling speed was set to 20 RPM and 60 RPM. MRF and EMG were measured in the vastus lateralis muscle of right leg. Active cycling was performed at the maximal load (16 Nm) of an ergometer. Angle dependent artifact in MRF was measured from passive cycling and was subtracted from the MRF of active cycling. The delay of MRF with respect to EMG envelope and their correlation coefficients were derived from the best of cross correlation. MRF was significantly correlated with EMG amplitude in all subjects (p<0.01). Their mean correlations were 0.84 and 0.91 for 20 RPM and 60 RPM, respectively. Mean delay in MRF was 59.14 ms and 53.14 ms for 20 RPM and 60 RPM, respectively. The result suggests that MRF can be used to assess patient's intention for exercise as a substitute to EMG. The method may be applied to FES cycling to encourage patient's effort which is critical for stroke rehabilitation.

• Journal of Mushroom
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• v.11 no.4
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• pp.187-193
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• 2013

A galactose fermentation bacterium producing lactose from red seaweed, which was known well to compromise the galactose as main reducing sugar, was isolated from button mushroom bed in Buyeo-Gun, Chungchugnamdo province. The lactic acid bacteria MONGB-2 was identified as Lactobacillus paracasei subsp. tolerans by analysis of 16S rRNA gene sequence. When the production of lactic acid and acetic acid by L. paracasei MONGB-2 was investigated by HPLC analysis with various carbohydrates, the strain MONGB-2 efficiently convert the glucose and galactose to lactic acid with the yield of 18.86 g/L and 18.23 g/L, respectively and the ratio of lactic acid to total organic acids was 1.0 and 0.91 g/g for both substrates. However, in the case of acetic acid fermentation, other carbohydrates besides galactose and red seaweed hydrolysate could not be totally utilized as carbon sources for acetic acid production by the strain. The lactic acid production from glucose and galactose in the fermentation time courses was gradually enhanced upto 60 h fermentation and the maximal concentration reached to be 16-18 g/L from both substrates after 48 h of fermentation. The initial concentration of glucose and galactose were completely consumed within 36 h of fermentation, of which the growth of cell also was maximum level. In addition, the bioconversion of lactic acid from the red seaweed hydrolysate by L. paracasei MONGB-2 appeared to be about 20% levels of the initial substrates concentration and this results were entirely lower than those of galactose and glucose showed about 60% of conversion. The apparent results showed that L. paracasei MONGB-2 could produce the lactic acid with glucose as well as galactose by the homofermentation through EMP pathway.

• Molecules and Cells
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• v.22 no.3
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• pp.336-342
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• 2006

Real time reverse transcription (RT)-PCR was used to quantify the expression of the botulinum neurotoxin type A (BoNT/A) gene (cntA) by normalization with the expression of 16S rRNA. The method were confirmed by monitoring the mRNA levels of cntA during growth in five type A strains. In all but one of the strains the expression of cntA mRNA was maximal in the late exponential phase, and approximately 35-fold greater than in the early exponential phase. The concentration of the extracellular BoNT/A complex detected by ELISA was highest in stationary phase. Sodium nitrite and sorbic acid completely inhibited growth at 20 ppm and $4mg\;ml^{-1}$, respectively. CntA expression became lower in proportion to the concentration of sorbic acid, and this reduction was confirmed by mouse bioassay. Our results show that real time RT-PCR can be used to quantify levels of C. botulinum type A neurotoxin transcripts and to assess the effects of food additives on botulinal risk.

• Journal of Microbiology and Biotechnology
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• v.22 no.10
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• pp.1412-1422
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• 2012

The aim of this work was to establish the optimal conditions for production of carboxymethylcellulase (CMCase) by a newly isolated marine bacterium using response surface methodology (RSM). A microorganism producing CMCase, isolated from seawater, was identified as Cellulophaga lytica based 16S rDNA sequencing and the neighborjoining method. The optimal conditions of rice bran, ammonium chloride, and initial pH of the medium for cell growth were 100.0 g/l, 5.00 g/l, and 7.0, respectively, whereas those for production of CMCase were 79.9 g/l, 8.52 g/l, and 6.1. The optimal concentrations of $K_2HPO_4$, NaCl, $MgSO_4{\cdot}7H_2O$, and $(NH_4)_2SO_4$ for cell growth were 6.25, 0.62, 0.28, and 0.42 g/l, respectively, whereas those for production of CMCase were 3.72, 0.54, 0.70, and 0.34 g/l. The optimal temperature for cell growth and the CMCase production by C. lytica LBH-14 were $35^{\circ}C$ and $25^{\circ}C$, respectively. The maximal production of CMCase under optimized condition for 3 days was 110.8 U/ml, which was 5.3 times higher than that before optimization. In this study, rice bran and ammonium chloride were developed as carbon and nitrogen sources for the production of CMCase by C. lytica LBH-14. The time for production of CMCase by a newly isolated marine bacterium with submerged fermentations reduced to 3 days, which resulted in enhanced productivity of CMCase and a decrease in its production cost.

• Korean Journal of Medicinal Crop Science
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• v.26 no.4
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• pp.308-316
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• 2018

Background: The Rosa multiflora, a well-known plant belonging to Rosacea, is widely used in orthodox medicine in worldwide. However, its biological activity and cosmetic preservative efficacy have not yet been studied. Thus, this species is yet to be defined as a functional cosmetic material. Accordingly, an investigation of the above mentioned atrributes was performed on a 50% ethanol extract of Rosa multiflora. Methods and Results: The antioxidant activity was assessed through free radical scavenging assays with 2,2-diphenyl-1-picrylhydrazyl (DPPH). Additionally, the contents of total phenols and flavonoids were analyzed. The phenolic compounds were detected using HPLC. The antimicrobial activity against Staphylococcus aureus, Escherichia coli, and Candida albicans was assessed using the disc diffusion assay. The preservative effect (challenge test) on a formulation of soothing gel was performed for 28days. The DPPH radical scavenging ability, denoted by the $SC_{50}$ (half maximal inhibitory concentration for DPPH radical scavenging) value was found to be $131.63{\mu}g/m{\ell}$. The content of total polyphenol and flavonoid content were 202 mg/g and 86.77 mg/g, respectively. In additon, astragalin and gallic acid were identified in the extract. The antimicrobial activity of the extract against S. aureus and E. coli was observed to be 5 - 0.5%, and no significant activity was noted against C. albicans. The ethanol extracts (5% and 10%) met the preservation standards of the Cosmetics, Toiletry, and Fragrance Association (CTFA). Conclusions: Thus the ethanol extract of R. multiflora can be used in cosmetics as a natural preservative and antioxidant.

• Journal of Microbiology and Biotechnology
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• v.31 no.2
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• pp.327-337
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• 2021

Fibrinolytic enzymes with a direct mechanism of action and safer properties are currently requested for thrombolytic therapy. This paper reports on a new enzyme capable of degrading blood clots directly without impairing blood coagulation. This enzyme is also non-cytotoxic and constitutes an alternative to other thrombolytic enzymes known to cause undesired side effects. Twenty-four Bacillus isolates were screened for production of fibrinolytic enzymes using a fibrin agar plate. Based on produced activity, isolate S127e was selected and identified as B. subtilis using the 16S rDNA gene sequence. This strain is of biotechnological interest for producing high fibrinolytic yield and consequently has potential in the industrial field. The purified fibrinolytic enzyme has a molecular mass of 27.3 kDa, a predicted pI of 6.6, and a maximal affinity for Ala-Ala-Pro-Phe. This enzyme was almost completely inhibited by chymostatin with optimal activity at 48℃ and pH 7. Specific subtilisin features were found in the gene sequence, indicating that this enzyme belongs to the BPN group of the S8 subtilisin family and was assigned as AprE127. This subtilisin increased thromboplastin time by 3.7% (37.6 to 39 s) and prothrombin time by 3.2% (12.6 to 13 s), both within normal ranges. In a whole blood euglobulin assay, this enzyme did not impair coagulation but reduced lysis time significantly. Moreover, in an in vitro assay, AprE127 completely dissolved a thrombus of about 1 cc within 50 min and, in vivo, reduced a thrombus prompted in a rat tail by 11.4% in 24 h compared to non-treated animals.

• The Korean Journal of Physiology and Pharmacology
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• v.28 no.4
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• pp.335-344
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• 2024

Diphenyleneiodonium (DPI) has been widely used as an inhibitor of NADPH oxidase (Nox) to discover its function in cardiac myocytes under various stimuli. However, the effects of DPI itself on Ca²⁺ signaling and contraction in cardiac myocytes under control conditions have not been understood. We investigated the effects of DPI on contraction and Ca²⁺ signaling and their underlying mechanisms using video edge detection, confocal imaging, and whole-cell patch clamp technique in isolated rat cardiac myocytes. Application of DPI suppressed cell shortenings in a concentration-dependent manner (IC₅₀ of ≅0.17 µM) with a maximal inhibition of ~70% at ~100 µM. DPI decreased the magnitude of Ca²⁺ transient and sarcoplasmic reticulum Ca²⁺ content by 20%-30% at 3 µM that is usually used to remove the Nox activity, with no effect on fractional release. There was no significant change in the half-decay time of Ca²⁺ transients by DPI. The L-type Ca²⁺ current (I_Ca) was decreased concentration-dependently by DPI (IC₅₀ of ≅40.3 µM) with ≅13.1%-inhibition at 3 µM. The frequency of Ca²⁺ sparks was reduced by 3 µM DPI (by ~25%), which was resistant to a brief removal of external Ca²⁺ and Na⁺. Mitochondrial superoxide level was reduced by DPI at 3-100 µM. Our data suggest that DPI may suppress L-type Ca²⁺ channel and RyR, thereby attenuating Ca²⁺-induced Ca²⁺ release and contractility in cardiac myocytes, and that such DPI effects may be related to mitochondrial metabolic suppression.

• 한국해양학회지
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• v.28 no.1
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• pp.1-16
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• 1993

The monthly mean sea levels at 48 stations located at the East and Yellow Seas coasts of Korea, Russia and Japan are processed to investigate seasonal sea level variations. The strong seasonal variations are found to be at the west coast of Korea (42.1 cm in Kunsan), in the region of the Korea strait and near the southern part of Primorye (30-33 cm); the weak ones near the southwestern coast of the Sakhalin Island (10-12 cm). Practically for the whole study area except the southwest Sakhalin, the general picture of the seasonal sea level changes is alike: the mean sea level rises in summer-autumn and falls in winter-spring. The spectral analysis of the records also shows that the seasonal oscillations strongly dominate in the sea level variations, more than 80% or total energy in the southern part of the investigated region and 50-70% in the northern part relate to these oscillations. The annal peak significantly prevails in spectra of the monthly sea levels for the majority of stations, the semiannual peak is also well manifested, but the seasonal peaks of higher order (corresponding to the periods of four and three months) reveal only at some records. The maximal amplitudes of annual component by a least square method are found at the Yellow Sea coast of Korea (20-21 cm) and also near the Japanese coast of the korea Strait (19-19 cm). The semiannual component has the maximal amplitudes (3-4 cm) near the south and southwestern coasts of the Sakhalin Island. The annual range of the sea levels is much weaker here than in the other regions, the relative investment of the seasonal oscillations in total energetic budget is only 35-40%, annual ($A_1$) and semiannual ($A_2$) components have nearly the same amplitude (seasonal factor $F=A_1/A_2=0.9-1.2$). On the basis of the present examination on sea level changes together with the results of Tomizawa et. al.(1984) the whole investigated area may be divided into 10 subregions, 2 of them are related to the Yellow Sea and Western part of the Korea Strait (Y1, Y2), the other ones (E1-E8) to the East Sea.

• Journal of Applied Biological Chemistry
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• v.56 no.4
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• pp.241-244
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• 2013

Nitrate is one of the major nutrients in plants, and nitrate fertilizer often overused for the high yields of crops. Nitrate deposit in soil became one of the major reasons causing salt stress. Specially, salt stress is a serious problem in the soils of plastic film or glass houses. In this study, six microorganisms have been isolated from the wet soils near the disposals of livestock farms and their nitrate uptake activities were investigated. These bacteria were able to remove nitrate as high as 1,000-3,000 ppm (10-50 mM). The strain PCE3 showed the highest nitrate uptake activity and it removed more than 3,700 ppm. In order to identify these bacteria, genes of 16S rRNA were sequenced and analyzed. Phylogenetic trees were constructed with the neighbor-joining methods. Among these bacteria, strain PCE3 was identified as Bacillus species. When the growth and nitrate uptake activities were measured, both were maximal at $37^{\circ}C$ and optimal pH was pH 7-9. Bacillus sp. PCE3 removed nitrate up to 40-60 mM (2,500-3,700 ppm) depending on the nitrate concentration in media. Therefore, Bacillus sp. PCE3 can be a good candidate for the microbial remediation of nitrate-deposited soils in glass and plastic film houses.

• Korean Chemical Engineering Research
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• v.56 no.6
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• pp.832-840
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• 2018

In this study, both of the concentration of benzo(a)pyrene in 5 species (total 50 samples) of medicinal herbs and their transfer ratios in the preparation steps of water extract(decoction) and soft extract, were measured by HPLC/FLD. The calibration curve of benzo(a)pyrene shows excellent correlation over the concentration range of 3~40 ng/mL with the correlation coefficient ($R^2$) of 1.000. The detected benzo(a)pyrene concentrations from the medicinal herbs ranged from non-detection to $37.54{\mu}g/kg$, and their average was $6.73{\mu}g/kg$. Among the total samples, 15 samples (i.e., 30%) exceeded the limit of herbal medicine benzo(a)pyrene criteria (i.e., $5{\mu}g/kg$) according to the notification No. 2009-302 from Ministry of Food and Drug Safety. In particular, the concentration of benzo(a)pyrene in Coptidis Rhizome was turned out to be the highest of $37.54{\mu}g/kg$. The detected benzo(a)pyrene concentrations from water extract(decoction), soft extract and remnant after boiling, ranged from non-detection to $2.31{\mu}g/kg$, non-detection to $2.28{\mu}g/kg$, and 2.18 to $21.91{\mu}g/kg$, respectively. In preparation of water extract(decoction) and soft extract, transferred benzo(a)pyrene was not detected or, if transferred, the maximal transfer ratios of benzo(a)pyrene were shown to be 8.9% and 9.8%, respectively. Therefore, the content of benzo(a)pyrene in the samples of herbal medicine used in this study, were reduced by more than 90% in preparation steps of water extract (decoction) and soft extract.