• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.29 no.5
• /
• pp.595-602
• /
• 1996

The antimicrobial effects of two disinfectants commonly used in food industry on Listeria monocytogenes ATCC 15313 were studied. The two disinfectants tested were commercial benzalkonium chloride (BAC) and sodium hypochlorite (NaOCl). Their effects were studied on cells suspended in disinfectants (in vitro) and in the sponge model with the disinfectants (in vivo). When cells were exposed to $0\~0.1\%$ BAC and $0\~150\;ppm$ NaOCL for 20 minutes, BAC and NaOCl concentration more than $0.25\%$ and 100 ppm showed the antimicrobial effects respectively. This organism decreased rapidly during the first $0.5\~1$ minute followed by a slower decrease during the rest of the exposure time. Fifteen ml of cell solution $(about\;10^7\;CFU/ml\;in\;the\;TSB)$ was mixed with 15 ml of disinfectants in the sponge $(6.0{\times}4.0{\times}4.0cm)$, BAC and NaOCl concentration more than $0.1\%$ and 300 ppm showed the antimicrobial effects, and at $0.25\%$ and 800 ppm diminished in cell numbers 3-log cycles during the first 20 minutes. In the case of sponge model, 15 ml of cell solution and 15 ml of disinfectants $(0.25\%\;of\;BAC,\;800\;ppm\;of\;NaOCl)$ were suspended in the sponge during 20 minutes, washing with 200 ml of sterilized distilled water, and this sponge was transfered in the 100 ml TBS, and then incubated at various temperature. The cells were increased about 1-log cycle during 24 hrs at $5\~15^{\circ}C$. And the others temperature, the cells growth was in proporation to storage tepmerature and the cells were about $10^9\;CFU/ml$ after $1\~3$ days incubations.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.31 no.6
• /
• pp.1084-1091
• /
• 2002

Mortierella alpina, a common soil fungus, is the most efficient organism for production of production acid presently known. Since arachidonic acid are important in human brain and retina development, it was undertaken the growing effect containing diet as a food ingredient. Arachidonic acid rich oil derived from Mortierella alpina, was subjected to a program of studies to establish for use in diet supplement. This study was compared the growth and learning effect of fungal oil rich in arachidonic acid by incorporated into diets ad libitum. Sprague-Dawley rats received experimental diets 5 groups (standard AIN 93 based control with beef tallow, extract oil 8%, and 4%, and Mortierella alpina in diet 10% and 20%) over all experiment duration (pre-mating, mating, gestation, lactation, and after weaning 4 weeks). Pups born during this period consumed same diets after wean for 4 weeks. There was no statistical significance of diet effects in reproductive performance and fertility from birth to weaning. But the groups of Mortierella alpine diet were lower of weight gain and diet intake after weaning. The serum lipids were significantly different with diet groups, higher TG in LO (oil 4%) group of dams, and higher total cholesterol in LF (M. alpina 10%) of pups, although serum albumin content was not significantly different in diet group. The spent-time and memory effect within 4 weeks of T-Morris water maze pass test in dam and 7-week- age pups did not differ in diet groups. On the count of backing error in weaning period of pups was lower in HO(extracted oil 8%) group. In the group of 10% and 20% Mortierella alpina diet, DNA content was lower in brain with lower body weight, but liver DNA relative to body weight was higher than control. Further correlation analyses would be needed DNA and arachidonic acid intakes, with Mortierella alpina diet digestion rate.

• Microbiology and Biotechnology Letters
• /
• v.41 no.1
• /
• pp.17-25
• /
• 2013

The thermotolerant methylotrophic yeast Hansenula polymorpha is an attractive model organism for various fundamental studies, such as the genetic control of enzymes involved in methanol metabolism, peroxisome biogenesis, nitrate assimilation, and resistance to heavy metals and oxidative stresses. In addition, H. polymorpha has been highlighted as a promising recombinant protein expression host, especially due to the availability of strong and tightly regulatable promoters. In this study, we investigated the possibility of employing human serum albumin (HSA) as the fusion tag for the secretory expression of heterologous proteins in H. polymorpha. A set of four expression cassettes, which contained the methanol oxidase (MOX) promoter, translational HSA fusion tag, and the terminator of MOX, were constructed. The expression cassettes were also designed to contain sequences for accessory elements including His8-tag, $2{\times}(Gly_4Ser_1)$ linkers, tobacco etch virus protease recognition sites (Tev), multi-cloning sites, and strep-tags. To determine the effects of the size of the HSA fusion tag on the secretory expression of the target protein, each cassette contained the HSA gene fragment truncated at a specific position based on its domain structure. By using the Green fluorescence protein gene as the reporter, the properties of each expression cassette were compared in various conditions. Our results suggest that the translational HSA fusion tag is an efficient tool for the secretory expression of recombinant proteins in H. polymorpha.

• Journal of Korean Society of Environmental Engineers
• /
• v.30 no.3
• /
• pp.271-277
• /
• 2008

The biofilm of white-rot fungi fully exposed in atmosphere are that operation is easy, management cost and energy waste is low. To develop biofilm of white-rot fungi fully exposed in atmosphere, basic test are as follows. To select most effective microoganism species, investigated treatment characteristics of wastewater containing non-biodegradable material for three species of white-rot fungi(Phanerochaete chrysosporium PSBL-1, Phanerochaete chrysosporium KCTC 6147, Trametes sp. KFCC 10941) and activated sludge. And then investigated attached and detached biomass of selected white-rot fungi species on HBC ring surface. Among the three strains tested, P. chrysosporium PSBL-1 and P. chrysosporium KCTC 6147 showed higher efficiency for organics removal than Trametes sp. KFCC 10941, and P. chrysosporium PSBL-1 showed higher efficiency for nitrogen removal than P. chrysosporium KCTC 6147 and Trametes sp. KFCC 10941. Respectively, 51$\sim$59.8%, 57.5$\sim$60.3% of NBDCOD was removed for P. chrysosporium PSBL-1 and P. chrysosporium 6147 in pH 3.5$\sim$5.5. TN removal efficiency showed 39.3$\sim$85.3%, 3.4$\sim$7.6% for P. chrysosporium PSBL-1 and P. chrysosporium 6147 in pH 4.5$\sim$11.5 respectively. Considered that white-rot fungi remove organism and nitrogen simultaneously, the microorganism selected white-rot fungi P. chrysosporium PSBL-1. White-rot fungi P. chrysosporium PSBL-1 attached on HBC ring surface 4,538 mg/L, 4,546 mg/L, 4,531 mg/L after 5 minutes, 4,575 mg/L, 4,573 mg/L, 4,568 mg/L after 10 minutes from initial MLSS 4,600 mg/L in pH 4, 7 and 10 respectively. Also detached biomass is negligible from right after attachment to 10 day in pH 4, 7 and 10.

• Journal of the Korean Society for Marine Environment & Energy
• /
• v.16 no.2
• /
• pp.88-101
• /
• 2013

The International Convention for the Control and Management of Ship's Ballast Water and Sediments was adopted at 2004 and then various BWMS (ballast water management system) have been developed. In this study, WET (whole effluent toxicity) test with algae (diatom) Skeletonema costatum as primary producer, invertebrate (rotifera) Brachionus plicatilis as 1st consumer and fish (olive flounder) Paralichthys olivaceus as predator, chemical analysis and ERA (environmental risk assessment) were conducted to assess the unacceptable effect on marine ecosystem by emitting the discharge water treated with AquaStar$^{TM}$ BWMS using electrolysis as main treatment equipment for removing the marine organisms in the ship's ballast water. The most sensitive test organism on discharge water treated with AquaStar$^{TM}$ BWMS was S. costatum that gave the NOEC value of 25.00%, LOEC value of 50.00% and 72hr-$EC_{50}$ value of 69.97% from WET test result for 20 psu salinity treated discharge water. NOEC and LOEC value of B. plicatilis and P. olivaceus exposed at 20 psu salinity treated discharge water were 50.00% and 100.00%, respectively. In the chemical analysis results, total number of substances produced by AquaStar$^{TM}$ BWMS was 18 which were bromate, 7 volatile halogenated organic compounds, 7 halogenated acetic acids, 3 halogenated acetonitriles and chloropicrin. Eighteen substances did not consider as persistence and bioaccumulative chemicals. Uncertainty of toxic property of 18 substances was high. PECs of 18 substances calculated by MAMPEC model were ranged from $4.58{\times}10^{-4}$ to $4.87{\mu}g\;L^{-1}$, PNECs of them were ranged from $1.6{\times}10^{-2}$ to $3.2{\times}10^2{\mu}g\;L^{-1}$. And, the PEC/PNEC ratio of 18 substances did not exceed 1. Therefore, ERA for produced substances indicate that the discharge water treated with AquaStar$^{TM}$ BWMS does not pose unacceptable effect on marine life. And $EC_{50}$ value of S. costatum on discharge water treated by BWMS using the electrolysis had positive correlation with initial TRO concentration, concentration and kind & level of HAAs.

• Korean Journal of Environmental Biology
• /
• v.38 no.1
• /
• pp.82-92
• /
• 2020

Since swine wastewater contains high concentrations of nutrients and heavy metals, it deteriorates water quality when discharged. Compared to conventional methods, bioremediation can be a promising method for its treatment. Specifically, microalgae have the potential to remove these pollutants. In this study, the removal of nutrients (nitrogen (N) and phosphorus (P)) and heavy metals (copper (Cu) and zinc (Zn)) from swine wastewater by Ankistrodesmus bibraianus was evaluated and the organism's optimal growth conditions were investigated. The optimal growth conditions were established at 28℃, pH 7, and light and dark cycles of 14:10 h. The removal efficiencies of N and P by a single treatment (500, 1,000, 5,000, and 10,000 mg L^-1) ranged from 22.9 to 80.6% and from 11.9 to 50.0%, respectively. The removal efficiencies of N and P in the binary treatments ranged from 16.4 to 58.3% and from 7.80 to 49.8%, respectively. The removal efficiencies of Cu and Zn by a single treatment(10, 30, and 50 mg L^-1) ranged from 15.5 to 81.5% and from 6.28 to 34.3%, respectively. Similarly, the removal efficiencies of Cu and Zn in the binary treatments ranged from 16.7 to 74.5% and from 5.58 to 27.5%, respectively. In addition, the study showed the optimal growth conditions for microalgae and the removal efficiency of nutrients (N and P) and heavy metals (Cu and Zn), which could be applied to swine wastewater. Based on the results in this study, it appears that Ankistrodesmus bibraianus could be used for the removal of nutrients and heavy metals present in swine wastewater.

• Pediatric Infection and Vaccine
• /
• v.5 no.1
• /
• pp.104-114
• /
• 1998

Purpose : Enteroviruses are the most common cause of aseptic meningitis. The epidemics of aseptic meningitis in 1993 and 1996 were mostly caused by echovirus type 9. Identification of the causative virus of aseptic meningitis in epidemics, is very important not only for diagnosis but also for epidemiologic purpose. The purpose of this study was to identify the causative virus and investigate the relationship between aseptic meningitis, prevailed in Masan and surrounding areas in Kyoungsangnamdo in 1997, and its clinical manifestations. Methods : One hundred twenty eight cerebrospinal fluid(CSF) and 239 stool specimens were obtained from 239 patients(213 children and 26 adult patients) with aseptic meningitis were admitted to Masan Fatima Hospitals from March to October 1997. Viral isolation and serotype identification was performed by cell culture and immunofluorescent test. Enteroviruses not typed by immunofluorescent test was confirmed by reverse transcription-polymerase chain reaction(RT-PCR). Results : 1) The peak incidence was noted in June. 2) The age of 239 patients(pediatrics-213 cases, internal medicine-26 cases) that were diagnosed ranged from neonate to 35 years, the age of the patients of pediatrics ranged from neonate to 15years(mean 4.9 years), the age of the patients of internal medicine (above 16 years) ranged from 16 years to 35 years(mean 24.2 years). 3) Fifty-three(41.4%) of 128 CSF specimens were positive for enteroviruses, and 163(68.2%) of 239 stool specimens were positive for enteroviruses respectively. 4) Serotypes of 53 enteroviruses isolated from CSF were 16(30.2%) of echovirus type 30, 6(11.3%) of echovirus type 6, 1 of echovirus type 4, 4 of untyped echovirus, 1 of coxsackievirus type B5, and 24 isolates of untyped enteroviruses. Of 163 enterovirus isolated from stool were 72(44.2%) of echovirus type 30, 21(12.9%) of echovirus type 6, 1 of echovirus type 4, 17(10.4%) of undetermined subtyped echovirus, 1 of coxsackievirus type B5, 2 of A24, 3 of undetermined subtyped coxsackievirus type B, and 46 isolates of untyped enterovirus. Conclusion : There were epidemics of aseptic meningitis in the central areas of Kyoungsangnamdo from March to October 1997. The main causative organism was thought to be the echovirus type 30, and echovirus type 4, 6, coxsackievirus B5 and A24 were also thought to contribute to the epidemics.

• Pediatric Infection and Vaccine
• /
• v.5 no.1
• /
• pp.79-87
• /
• 1998

Purpose : The P1 protein of Mycoplasma pneumoniae mediates the attachment of the pathogen to its host cell and elicits a strong humoral immune response during infection with this organism. Mycoplasma pneumoniae strains can be classified into two groups(I and II) by PCR method of P1 cytadhesin gene. In this study, we evaluated the prevalence, epidemiological and clinical characteristics of each group. Methods : From 155 patients with Mycoplasma pneumoniae, who admitted to the Department of Pediatrics, Sung-Ae and Kwangmyung Sung-Ae Hospital between November 1996 and October 1997, we collected their throat swabs or nasopharyngeal aspirates for DNA extraction and serum for indirect hemagglutination test of Mycoplasma pneumoniae. The group specific PCR amplification were performed using specific oligonucleotide primers designed for P1 gene genotyping. Results : Group I(137 patients, 88.4%) occurred frequently than group II(18 patients, 11.6%). In both group, the most prevalent season was winter in 1996(Nov. to Dec.) and fall in 1997(Aug. to Oct.) The prevalent age was four to six years old. The number of male was more than female in both group; Group 1(1.2:1), Goup 2(1.6:1). No significant relationship were found between two groups in duration of fever and hospital days(P>0.05). The rate of high antibody titers(>1:5120) was lower in group I(6/137, 4.4%) than group II(2/18, 11.1%). Conclusion : Group I was much more prevalent than group II during 1996~1997 in Korea. There was no difference between two groups in epidemiological and clinical parameters except the rate of high antibody titers. Further follow-up survey will be needed for the epidemiologic and clinical studies of Mycoplasma pneumoniae in Korea.

• Pediatric Infection and Vaccine
• /
• v.11 no.1
• /
• pp.90-100
• /
• 2004

Objective : Urinary tract infection(UTI) is a frequent serious bacterial infection in young infants. The clinical presentation may be non-specific and variable, depends on factors such as the age and the level of infection. Children with renal involvement may be at risk of permanent renal damage. Experimental studies have shown that renal lesions caused by acute febrile UTI may be prevented or diminished by early diagnosis and treatment. Therefore, it is important to find a method that can permit early diagnosis and identification of patients who are at risk for progressive renal damage. We designed this study to identify related factors in culture positive UTI infants, and also to identify related factors in culture negative UTI infants, who are febrile with pyuria, by using renal imaging and functional studies including renal sonography, DMSA scan and VCUG. Methods : Retrospectively analyzed the medical records of 136 febrile infants with pyuria over 2 years(from January 2001 to February 2003). Urine culture was done in all cases, and regardless of urine culture findings, renal imaging study was done if symptomatic UTI suspected. Results : Total 57 organisms were isolated in 53 patients. E. coli was the most common organism(86%), followed by E. faecalis, M. morganii, Proteus species, P. aeruginosa, S. aureus and E. fergusonii. Most of the isolates had high sensitivity on cephalosporins or amikacin and had low sensitivities on aminopenicillins. Abnormal acute phase DMSA scan or VCUG findings were seen in both urine culture positive and negative group without statistical differences(P>0.05). In febrile infants with pyuria, fever over 48 hours, older age and high CRP related to abnormal acute phase DMSA scan findings regardless urine culture results. Conclusion : 1st or 3rd generation cephalosporins with amikacin could be the first choice of treatment for UTI. Febrile infants with positive urine culture dose mean urinary tract infection but not acute pyelonephritis which directly relates to cortical damage which could be confirmed by acute phase DMSA scan. Even cases with negative urine culture findings, acute pyelonephritis should be concerned in febrile infants with pyuria who are older than 3 months of age, has fever over 48 hours or high CRP level. And in such cases, acute phase DMSA scan and VCUG should be evaluated for early treatment and long term prognosis.

• Pediatric Infection and Vaccine
• /
• v.12 no.1
• /
• pp.86-94
• /
• 2005

Purpose : Recently, it has been reported that the prevalence of mycoplasam pneumonia in infants is increasing. We studied the change of prevalence and clinical features in infants for recent three years. Methods : We evaluated the clinical records of 206 patients diagnosed as mycoplasma pneumonia during Mar. 2000~Feb. 2003. We retrospectively analyzed epidemiologic, clinical, serologic and radiologic difference between children younger than 24 months and others. Results : Among 206 patients, 111 were boys and 95 were girls. Mean age of onset was $5.12{\pm}2.91$ years and lowered annually(P>0.05). 28 patinets(13.6%) were younger than 24 months and annual prevalence in this group increased(P<0.05). Main clinical features included cough, fever, coarse breathing sound(=sputum), rhinorrhea and dyspnea. There was no clinical difference between children younger than 24 months and others, except for rhinorrhea and dyspnea which more developed frequently in children younger than 24 months (P<0.05). There was also no serologic and radiologic difference for these groups. Conclusion : Annual mean age of onset lowered and annual prevalence of younger than 24 months increased with mycoplasma pneumonia. Therefore, we need careful attention to differentiate Mycoplasma pneumoniae as causal organism of pneumonia in children younger than 24 months.