• Journal of Microbiology and Biotechnology
• /
• v.23 no.3
• /
• pp.397-404
• /
• 2013

Paenibacillus xylanilyticus KJ-03 was isolated from soil samples obtained from a field with Amorphophallus konjac plants. A gene encoding xylanase was isolated from KJ-03 and cloned using a fosmid library. The xynA gene encodes xylanase; it consists of 1,035 bp and encodes 345 amino acids. The amino acid sequence deduced from the P. xylanilyticus KJ-03 xylanase showed 81% and 69% identities with those deduced from the P. polymyxa E681 and Paenibacillus sp. HPL-001 xylanases, respectively. The xynA gene comprises a single domain, consisting of a catalytic domain of the glycosyl hydrolase (GH) 10 family. The xynA gene was expressed in Escherichia coli BL21 (trxB), and the recombinant xylanase was purified by Niaffinity chromatography. The purified xylanase showed optimum activity with birchwood xylan as a substrate at $40^{\circ}C$ and pH 7.4. Treatment with $Mg^{2+}$ and $Li^+$ showed a slight decrease in XynA activity; however, treatment with 5 mM $Cu^{2+}$ completely inhibited its activity. The results of the thin layer chromatography analysis indicated that the major hydrolysis product was xylobiose and small amounts of xylose and xylotriose. XynA showed increased activity with oat spelt xylan and birchwood xylan, but showed only slight activity with locust bean gum.

• Parasites, Hosts and Diseases
• /
• v.58 no.6
• /
• pp.695-699
• /
• 2020

Present study was performed to know the infection status of Gnathostoma sp. larvae in swamp eels from Cambodia. We purchased total 30 Asian swamp eels, Monopterus albus, from local markets in Pursat and Takeo Provinces and Phnom Penh on May and November 2017 and May 2018. All collected eels were transferred to our laboratory with ice and each of them was examined by artificial digestion method. A total of 15 larval gnathostomes (1-5 larvae) were detected from 55.6% (5/9) swamp eels in Pursat Province. No larval gnathostomes were found in 21 swamp eels in Takeo Province and Phnom Penh. The advanced third-stage larvae (AdL3) detected were 2.575-3.825 (3.250) mm in length and 0.375-0.425 (0.386) mm in width. They had the characteristic head bulb (av. 0.104×0.218 mm) with 4 rows of hooklets, long muscular esophagus (1.048 mm), and 2 pairs of cervical sacs (0.615 mm). The number of hooklets in 4 rows on the head bulb was 41, 44, 47, and 50. In scanning electron microscopy, characteristic features were 4 rows of hooklets on the head bulb, cervical papillae, tegumental spines regularly arranged in transverse striations, and anus. The larval gnathostomes were identified as AdL3 of Gnathostoma spinigerum based on the morphological characters. By the present study, it has been confirmed that G. spinigerum larvae are infected in Asian swamp eels, M. albus, in Pursat Province, Cambodia.

• Korean Journal of Food Science and Technology
• /
• v.23 no.6
• /
• pp.661-666
• /
• 1991

European style fermented sausages were made with normal pork, PSE and a 50 : 50 mixture, inoculated with Lactobacillus plantarum 1-74 and Staphylococcus simulans MIII and ripened for 21 days following commercial manufacturing procedures. In all treatments, pH droped sharply between 0 and 3 days during ripening. PSE sausages showed the lowest pH and Aw at the end of ripening than other treatment groups. Protein solubility, hardness, cohesiveness and chewiness were significantly (P<0.05) low for PSE sausages. Springiness was the highest for normal sausages but the other two treatment were not different. PSE sausages had poor texture low redness value during the ripening. The added sugars apparently dropped the pH fast in PSE sausages. Total bacterial count and lactobacilli increased from 0 day to the third day of ripening. The number of Staphylococcus sp. decreased in normal sausages by the end of the ripening period. Fermented sausages with PSE meat could be produced if the mixture had lower (<50%) amounts of PSE meat. In addition, added sugar must be reduced to prevent lowering the pH to a level that will affect processing and quality attributes of fermented sausages.

• Journal of Korean Society on Water Environment
• /
• v.27 no.6
• /
• pp.848-854
• /
• 2011

The objective of this research was to experimentally test the effect of rice straw mats on the reduction of runoff, sediment and discharge under a laboratory scale with different rainfall intensity and slopes. We used the small runoff plots of $1m{\times}1m{\times}0.65m$ ($L{\times}W{\times}H$) in size were filled with loamy sand. Experimental treatments were bare (control), rice straw mats + PAM(SP), rice straw mats + PAM + sawdust(SPS) and rice straw mats + PAM + rice husks(SPR); slope of 10% or 20%; and rainfall intensity of 30 or 60 mm/hr. Runoff volume and coefficient from covered plots were significantly lower than those from control plots. Under the 30 mm/hr and 10% simulations, average runoff coefficient of covered plots decreased more than 92%. Under 60 mm/hr and 20% simulations, the ratios were between 39.8~58.1%. Under the condition of 30 mm/hr rainfall and 10% slope, sediment discharge from covered plots was practically zero. And at 20% plots, sediment reduction ratio was more than 95%. Under the condition of 60 mm/hr rainfall, sediment reduction ratio of 10 and 20% plots ranged between 86.3~95.3% and between 79.8~86.5%, respectively. The differences in initial runoff time, runoff and sediment discharge among different cover materials were not significant. Rainfall intensity showed higher impact on initial runoff time, runoff, and sediment discharge than slope. It was also shown that even if runoff reduction by surface cover were low, sediment discharge reduction could be very significant and contribute to improve the water quality of streams in sloping agricultural regions. It was concluded that the use of straw mat and PAM on sloping agricultural fields could reduce soil erosion and muddy runoff significantly and help improve the water quality and aquatic ecosystem in receiving waters.

• Korean Journal of Microbiology
• /
• v.49 no.2
• /
• pp.118-125
• /
• 2013

Antibiotic susceptibility was examined for 596 Salmonella isolates from patients with acute gastroenteritis during 2000-2009 in Gwangju area in South Korea. Of 16 antibiotics tested, ampicillin resistance (43%) was the most commonly observed resistance among the 596 Salmonella sp. isolates, followed by tetracycline (35.9%), nalidixic acid (31.5%), and chloramphenicol (26.2%). Antibiotic resistance varied among serotypes: The highest resistance of S. Enteritidis and S. Typhimurium was to ampicillin (51.1%) and tetracycline (77.9%), respectively. A total of 89 resistance patterns were observed, and 26% (155/596) of Salmonella isolates were susceptible to all antibiotics tested in this study. About 21% (127/596) and 15% (87/596) of the isolates were resistant to one and two antibiotics, respectively. The rest of Salmonella isolates (227/596, 38%) were resistant to three or more antibiotic agents. The highest multi-drug resistance (MDR) was observed in serotype S. Paratyphi B (76.5%), followed by S. Typhimurium (58.2%), and S. Enteritidis (40.2%). The most common resistance pattern of MDR isolates was ampicillin-chloramphenicol-nalidixic acid-ticarcillin (36/227, 15.8%), most of which (35/36, 97.2%) were S. Enteritidis.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.21 no.1
• /
• pp.42-51
• /
• 2007

An AC electrical railroad system has rapidly changing dynamic single-phase load, and at a feeding substation, three-phase electric power is transformed to the paired directional single-phase electric power. There is a great difference in electrical phenomenon between the load of AC electrical railroad system and that of general power system. Electric characteristics of AC electrical railroad's trainload are changed continuously according to the traction, operating characteristic, operating schedule, track slope, etc. Because of the long feeding distance of the dynamic trainload, power quality problems such as voltage drop, voltage imbalance and harmonic distortion my also occur to AC electrical railroad system. These problems affect not only power system stability, but also power quality deterioration in AC electrical railroad system. The dynamic simulation model of AC electrical railroad system presented by PSCAD/EMTDC is modeled in this paper, andthen, it is analyzed voltage drop for AC electrical railroad system both with single-phase distributed STATCOM(Static Synchronous Compensator) installed at SP(Sectioning Post) and without.

• Polymer(Korea)
• /
• v.27 no.5
• /
• pp.464-469
• /
• 2003

In this work, the fragrant oil release behavior of poly($\varepsilon$-caprolactone) (PCL) microcapsules containing SiO$_2$ was investigated. The SiO$_2$ was chemically treated in 10, 20, and 30 wt% hydrochloric acid and sodium hydroxide. The acid and base values were determined by Boehm's titration technique and $N_2$/77 K adsorption isotherm characteristics, the specific surface area and total pore volume were studied by BET. The PCL microcapsules containing SiO$_2$ and fragrant oil were prepared by oil-in-water (o/w) emulsion solvent evaporation method. The shape and surface of PCL microcapsules were observed using image analyzer and scanning electron microscope (SEM). The fragrant oil release behavior of PCL microcapsules was characterized using UV/vis. spectra. The average diameters of PCL microcapsules were decreased from 35 to 21 $\mu$m with increasing stirring rate. It was found that in the case of acidic treatment the fragrant oil adsorption capacity and release rate were increased due to the increase of specific surface area and acid value. In the case of basic treatment, the fragrant oil adsorption capacity and release rate were decreased due to the decrease of sp ecific surface area and the increase of acid-base interactions between SiO$_2$-NaOH and fragrant oil with increasing base value of SiO$_2$.

• Journal of Fisheries and Marine Sciences Education
• /
• v.3 no.2
• /
• pp.29-46
• /
• 1991

Benthic marine algal community of a sea bank at Joomoonjin, in the eastern coast of Korea, was investigated monthly in view of floristic composition and seasonal periodicity during from August, 1989 to July 1990. Total number of benthic alga identified were 70 taxa, which composed of 7 species of Chlorophyta, 21 species of Phaeophyta and 42 species of Rhodophyta. The dominant species were Sargassum horneri, Underia pinnatifida, Laminaria japonica and Pachymeniopsis sp.. Vegetation, from the point of phygiognomy, was a mosaic type by these dominant species. The flora was compared with similarity index using S${\phi}$rensen coefficient and grouped by a cluster analysis. As a result, the algal community of this area could be divided into two clusters at similarity level 45% : Flora of water temperature-ascending period(January-July) and flora of water temperature-descending period(August-December). And also, the former flora was subdivided into two clusters at point of the $14^{\circ}C$ sea water temperature : winter flora(January-April) and spring-summer flora(May-July). The flora of this area was characterized as a mixed flora of cold and temperature zone by Cheney's index.

• Journal of Yeungnam Medical Science
• /
• v.18 no.1
• /
• pp.67-74
• /
• 2001

Background: Meralgia paresthetica(MP) which is characterized by paresthesias and sensory impairment without motor weakness in the anterolateral aspects of the thigh is produced by compression of the lateral femoral cutaneous nerve(LFCN). Even though the diagnosis of MP is mostly based on the clinical symptoms, electrophysiologic study is mandatory to confirm the disease objectively. It has been known that Somatosensory evoked potential(SSEP) study of LFCN is a simple and very useful method to evaluate MP, so we studied SSEP of LFCN in normal adults and offer normal values. Materials and Methods: Thirty six normal adults(23 males and 13 females) ages from 21 to 73 years old($mean{\pm}SD$:$42.06{\pm}15.74$) were studied SSEP of LFCN bilaterally. The stimulation site was anterolateral aspect of thighs and the recording site was Cz'. Results: The mean values($mean{\pm}SD$) of $LP_0$, $SP_0$, $LN_1$ and $SN_1$ of all subjects were 35.10(${\pm}2.42$), 33.80(${\pm}2.4$), 43.68(${\pm}1.88$) and 42.16(${\pm}2.12$) and the mean values($mean{\pm}SD$ of $DP_0$, $DN_1$ and DA(${\mu}V{\pm}SD$ were 1.30(${\pm}1.14$), 1.52(${\pm}1.38$) and 0.32(${\pm}0.33$). Conclusion: For the diagnosis of MP. comparison of latency difference between both sides is more reliable than simple value of latency itself because of individual differences of body types. According to our results. the latency difference should be less than 2 msec and the amplitude difference was less than 1.6 times in normal adults.

• Food Science and Biotechnology
• /
• v.17 no.3
• /
• pp.519-526
• /
• 2008

To improve the quality of traditional kochujang, strains with high protease and amylase activity were isolated and identified from Sunchang traditional kochujang. Twenty-three strains strongly producing protease and 16 strains strongly producing $\alpha$- and $\beta$-amylase were isolated by using 1% isolated soy protein agar medium and 2% starch agar medium, respectively. Protease activities of the IA7, I5, and IA2 strain were 22.5, 21.2, and 20.6 unit/mL, respectively, and were higher than those of the other strains. Stains with high $\alpha$-amylase activity included K9 (967.8 unit/mL), K14 (828.3 unit/mL), K13 (662.5 unit/mL), K8 (601.5 unit/mL), and K11 (405.9 unit/mL). The $\beta$-amylase activity of the K11 strain was the highest, 34.3 unit/mL, among the isolated strains. Based on morphological, physiological properties, and API 50CHB-kit test for assimilation of 49 carbohydrates, 8 strains selected according to protease, $\alpha$-amylase, and $\beta$-amylase activities were tentatively identified as Bacillus megaterium (IA2), Bacillus subtilis (IA7, 15), Bacillus amyloliquefaciens (K8, K9, K11, and K13), and Bacillus stearothermophillus (K14). The IA7, 15, and K11 strains were finally identified as B. subtilis (99% ID) based on 16S rDNA sequencing.