• Korean Journal of Poultry Science
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• v.32 no.1
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• pp.43-48
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• 2005

An experiment was conducted to investigate the effects of mineral extract from granite on the performance, ammonia production from the litter, components of blood, Newcastle Disease (ND) titer and intestinal microflora in broiler chickens. Nine hundred sixty one-day-old broiler chickens (Ross) were assigned to five treatments: C; control, Zeolite; control + zeolite 1$\%$, AM10: control + active mineral water $10\%$ adsorbed zeolite $1\%$, AM20; control + active mineral water $20\%$ adsorbed zeolite $1\%$ and AM30; control + active mineral water $30\%$ adsorbed zeolite $1\%$. Each treatment consisted of four replicates with 48 broiler chicks for feeding trial. In order to test the effect of ND vaccine on the components of blood, ND titer and intestinal microflora, a separate group of 48 broiler chicks were assigned to the same 5 treatment as the feeding trial plus one negative control (No ND vaccine). Weight gain, feed intake, feed conversion and mortality were not significantly affected by dietary treatments but AM30 tended to be higher than other treatments in weight gain and feed intake, especially during later period (4 to 5 weeks of age). Ammonia production from the litter of AM30 treatment was significantly (P<0.01) lower than the control. Components of blood and ND titer in serum of broiler chickens were not significantly affected by treatments but MCHC (mean corpuscular hemoglobin concentration) of blood was significantly lower (P<0.05) in Zeolite treatment compared to others. The colony forming unit (CFU) of Clostridium perfringens in the small intestinal content of all zeolite and AM treated groups was significantly (P<0.01) lower than the control while the CFU of Escherichia coli was not significantly affected. The CFU of Lactobacilli in AM30 treatment was significantly (P<0.05) higher than the control. In conclusion, dietary supplement of active mineral water adsorbed to zeolite at $30\%$ level (AM30) tended to improve growth performance of broiler chickens and significantly reduced ammonia production from the litter. It also significantly increased CFU of intestinal Lactobacilli.

• Journal of agriculture & life science
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• v.46 no.3
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• pp.97-108
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• 2012

Physical, chemical and biological hazards of strawberry farms at the cultivation stage were analyzed to establish the GAP(Good Agricultural Practice) system. Samples were collected from the plants, cultivation environments(water, soil and air), and personal hygiene (hand, glove, and clothes) of three strawberry farms(A, B, and C) and were tested to analyze physical, chemical (heavy metals and pesticide residues), and biological(sanitary indications and foodborne pathogens) hazards. Physical hazards such as insects and pieces of metal and glass were found in the strawberry farms and can be potential bow for strawberry products. Heavy metal and pesticide residue as chemical hazards were detected at levels lower than the regulation limit. In case of biological hazards, total bacteria and coliform were detected at the levels of 1.6~7.3 and 1.3~5.6 log CFU/g, leaf, mL, hand or $100cm^2$. However, Escherichia coli was not detected in all samples. Bacillus cereus and Staphylococuus aureus were detected at levels of ${\leq}$ 1.1~6.1 log CFU and 4.7~5.4 log CFU/g, mL, hand or $100cm^2$, whereas Listeria monocytogenes, E. coli O157 and Salmonella spp. were not detected in all samples. This study demonstrates that various harzards were in strawberry farms at the growing stage. Therefore proper management such as GAP is needed to prevent the occurrence of food poisoning associated with the hazards revealed in this study.

• Journal of agriculture & life science
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• v.46 no.4
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• pp.141-153
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• 2012

Samples collected from six tomato farms(A, B, C : soil culture, D, E, F : Nutriculture) located in Gyeongsangnam-do were tested for the analyses of biological(sanitary indications, major foodborne pathogens, fungi), chemical(heavy metals, pesticides) and physical hazards. The highest levels of total bacteria(7.5 log CFU/g) and coliforms(5.0 log CFU/g) in soil culture farms were higher than those of nutriculture farms(total bacteria: 2.5 log CFU/mL, coliforms: 0.6 log CFU/mL). In crops and personal hygiene soil culture farms showed a slightly higher contamination levels. From all farms, the levels of fungi in soil farms were higher than those of nutrient solution. In case of major pathogens, Bacillus cereus and Staphylococcus aureus were detected in all sample with the exception of nutrient solution. Meantime, Escherichia coli, Listeria monocytogenes, E.coli O157 and Salmonella spp. were not detected. For airborne bacteria, soilculture farms showed less contamination than nutriculture farms. A piece of glass and can was confirmed asphysical hazards. Heavy metal(Cd, Pb, Cu, Cr, Hg, Zn, Ni and As) and pesticide residues as chemical hazards were detected, but their levels were lower than the regulation limit. These results demonstrate that potential hazards on harvesting stage of tomato fam were exposed. Therefore, proper management is needed to prevent biological hazards due to cross-contamination, while physical and chemical hazards were in appropriate levels based on GAP criteria.

• Journal of Food Hygiene and Safety
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• v.37 no.2
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• pp.87-96
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• 2022

Recently, the purchase of fresh-cut produce and meal kits has increased. Ready-to-eat (RTE) fresh-cut products have potentially hazard of cross-contamination of various microorganisms in the processes of peeling, slicing, dicing, and shredding. There are frequent cases of protozoa food poisoning, such as Cyclospora and Cryptosporidium, caused by fresh-cut products. The objective of the study is to investigate the microbiological qualities of various types of RTE fresh-cut products in the domestic on/offline markets. RTE fresh-cut fruits cup (n=100), fresh-cut vegetables (n=50), and vegetables in meal kits (Vietnamese spring rolls and white radish rolls kits, n=50) were seasonally analyzed. The contamination levels of hygienic indicator organisms, yeast and mold (YM), and foodborne pathogens (Bacillus cereus, Staphylococcus aureus, Listeria monocytogenes, Salmonella spp., and Escherichia coli O157:H7) were monitored. Overall, the lowest microbiological qualities of meal kits vegetables were observed, followed by RTE fresh-cut fruits cup and fresh-cut vegetables. Contamination levels of total aerobic bacteria, coliforms, and YM in meal kits vegetables were 5.91, 3.90, and 4.71 logs CFU/g, respectively. From the qualitative analysis, 6 out of 200 RTE fresh-cut products (3%) returned positive result for S. aureus. From the quantitative analysis, the contamination levels of S. aureus in purple cabbage from a meal-kit and fresh-cut pineapple were below the acceptable limit (100 CFU/g). Staphylococcus enterotoxin seg and sei genes were detected in RTE fresh-cut celery and red cabbage from meal-kits, respectively. S. aureus contamination must be carefully controlled during the manufacturing processes of RTE fresh-cut products. Neither Cyclospora cayetanensis nor Cryptosporidium parvum was detected in the samples of RTE fresh-cut products and vegetables from meal-kits from the Korean retail markets.

• Journal of Chest Surgery
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• v.36 no.8
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• pp.545-558
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• 2003

Adult respiratory distress syndrome (ARDS) is of particular interest because of its severity of the associated lung injury and its high mortality. However, the pathophysiologies of ARDS in infant and childhood groups are still not well clarified inspite of many previous investigations. To investigate the time course of pathophysiology of ARDS in infant and childhood groups, this study was designed with experimental endotoxin-induced ARDS model using young rabbits (8 week-old). Material and Method: Rabbits were divided into the control group (n=8) and the endotoxin-treated group (n=32). The endotoxin group was subdivided into 4 groups by the sampling times as 3, 6, 12 and 24 hr-groups (G- $E_{3,6,12,24,}$ each n=8). The experimental ARDS was made by a bolus injection of endotoxin (Escherichia coli serotype 055 : B5, 0.50 mg/kg) via rabbit ear vein. For evaluation of the hematologic and inflammatory markers, and superoxide dismutase (SOD) concentrations, the blood samples were taken from the heart. The bronchoalveolar lavage fluid (BALF) were obtained for analysis of the leukocytes and protein concentration. With biopsy of the lung, histopathologic changes of the lung were also evaluated. Result: In the endotoxin groups, significant leukopenia (owing to pancytopenia) occurred in 3 and 6-hr groups, which was followed by significant leukocytosis (owing to neutrophilia) in the 12 and 24-hr groups (p<0.05). Serum levels of tumor necrosis factor-$\alpha$ (TNF-$\alpha$) and interleukin-1 $\beta$ (IL-1 $\beta$) in the endotoxin groups were higher than those of control group (p<0.05). Serum levels of superoxide dismutase (SOD) of G- $E_{3}$ and G- $E_{6}$ were higher than those of control group, whereas those of G- $E_{12}$ were lower than those of control groups (p<0.05). Total leukocyte counts and protein con-centrations in BALF were significantly elevated in the endotoxin groups compared to the control group (p < 0.05). The hemorrhagic pattern of BALF showed occurred in the endotoxin groups. The endotoxin groups (in G- $E_{6}$) had severe infiltration of inflammatory cells (lymphocyte and monocyte) in the pulmonary interstitium and parenchyma, migrations of neutrophil and eosinophil into alveolar spaces and interstitial widening, which are the evidences of acute lung injury. In the endotoxin groups, there were significant positive correlations between the BALF findings and the immunologic markers (TNF-$\alpha$, IL-1$\beta$, SOD) (p<0.05). Conclusion: Severe acute lung injury occurred in all the endotoxin-treated rabbits. The pathophysiologic findings were so progressive until 6-hr by time dependant pattern, and then recovered slowly, Variable hematologic, immuno-logic, and pathologic factors were well correlated in the development and progression of endoxin-induced lung injury. The pathophysiologic responses were sensitive and rapid in young rabbit Young rabbit seemed to be a useful experimental animal model for infant and childhood groups.roups.

• Journal of Food Hygiene and Safety
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• v.34 no.6
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• pp.583-590
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• 2019

As the consumption of fresh fruits and vegetables increases, food poisoning caused by foodborne pathogen contamination is not decreasing. To prevent the contamination of produce, a quick and easy, low-cost, environmentally-safe disinfection method that does not affect produce freshness or quality is needed. This study demonstrates a new-concept, circulating-water disinfection system that purifies water by using newly developed 'LED-PS (photosensitizer)-induced ROS generation unit'. Using various types of LED-PS induced ROS generation units, we investigated the conditions for reducing the density of various pathogenic bacteria by more than 3 log CFU / mL in 1 hour. The major operational factors affecting the density reduction of the LED-PS-induced ROS generation unit were analyzed. Depending on bacteria species, the density reduction rate was varied. The effect of the units on reducing the density of Bacillus cereus and Pectobacterium carotovorum subsp. carotovorum was high, but the effect on foodborne bacteria such as Escherichia coli was relatively low. In this circulating water disinfection system, the density reduction effect tended to increase as the flow rate increased and the initial bacterial density decreased. As the amount of PS absorbed beads increased, the density reduction effect increased exponentially in some bacteria. Model 3280, a double cylindrical unit connecting two single cylindrical units, could completely sterilize more than 3 log CFU/mL of B. cereus and P. carotovorum subsp. carotovorum in 30 minutes of LED irradiation.

• Nuclear Medicine and Molecular Imaging
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• v.43 no.5
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• pp.487-494
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• 2009

Purpose: Small size of recombinant scFv antibody has many advantages such as rapid blood clearances and improved targeting antibodies to tumor region. On the other hand owing to small size, number of amino group is insufficient in conjugation with chelator and fluorescence labeling. This study is to introduce poly lysine tag to the C-terminal end of scFv lym-1 sequence for fluorescence chelator conjugation. Materials and Methods: Poly lysine scFv lym-1 gene, cloned into pET-22b (+) vector, was expressed in E. coli BL21 (DE3) strain. Antibody purification was performed with Ni-NTA column and then size exclusion column chromatography. Expression and purification levels of poly lysine tagged scFv lym-1 antibody were confirmed by western blot analysis. I-124, I-125, I-131 and Tc-99m were used for radiolabeling of purified poly lysine scFv lym-1. Flow cytometry analysis of FIT( conjugated poly lysine scFv lym-1 was performed for confirmation of immunoreactivity of human Burkitt's lymphoma cells. Results: Poly lysine scFv lym-1 antibody was purified through two steps and identified as molecular weight of 48 KDa. Radiolabeling yields of I-124, I-125, I-131 and Tc-99m into poly lysine scFv lym-1 were >99%, >99%, >95% and >99%, respectively. Flow cytometry analysis of poly lysine scFv and scFv lym-1 was showed similar immunoreactivity to human Burkitt's lymphoma cells. Conclusion: Poly lysine tag was useful for the sufficient number of amino groups to scFv lym-1 antibody for chelator conjugation with minimizing loss of immunoreactivity.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.8
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• pp.1181-1188
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• 2013

Two experiments were conducted to evaluate the effect of supplementing a corn-soybean meal-based diet with an enzyme complex containing amylase, protease and xylanase on the performance, intestinal health, apparent ileal digestibility of amino acids and nutrient digestibility of weaned pigs. In Exp. 1, 108 piglets weaned at 28 d of age were fed one of three diets containing 0 (control), 100, or 150 ppm enzyme complex for 4 wks, based on a two-phase feeding program namely 1 to 7 d (phase 1) and 8 to 28 d (phase 2). At the end of the experiment, six pigs from the control group and the group supplemented with 150 ppm enzyme complex were chosen to collect digesta samples from intestine to measure viscosity and pH in the stomach, ileum, and cecum, as well as volatile fatty acid concentrations and composition of the microflora in the cecum and colon. There were linear increases (p<0.01) in weight gain, gain: feed ratio and digestibility of gross energy with the increasing dose rate of enzyme supplementation during the whole experiment. Supplementation with enzyme complex increased the digesta viscosity in the stomach (p<0.05) and significantly increased (p<0.01) the concentrations of acetic, propionic and butyric acid in the cecum and colon. Enzyme supplementation also significantly increased the population of Lactobacilli (p<0.01) in the cecum and decreased the population of E. coli (p<0.05) in the colon. In Exp. 2, six crossbred barrows (initial body weight: $18.26{\pm}1.21$ kg), fitted with a simple T-cannula at the distal ileum, were assigned to three dietary treatments according to a replicated $3{\times}3$ Latin Square design. The experimental diets were the same as the diets used in phase 2 in Exp. 1. Apparent ileal digestibility of isoleucine (p<0.01), valine (p<0.05) and aspartic acid (p<0.05) linearly increased with the increasing dose rate of enzyme supplementation. In conclusion, supplementation of the diet with an enzyme complex containing amylase, protease and xylanase improved piglet performance. This is likely a result of improvement in nutrient digestibility, volatile fatty acid concentrations and bacteria ratio in the large intestine.

• Journal of Life Science
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• v.30 no.3
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• pp.304-312
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• 2020

Agarase can be used in the field of basic science, as well as for production of agar-derived high-functional oligosaccharides and bioenergy production using algae. In 2012, we summarized the classification, origin, production, and applications of agar. In this paper, we briefly review the literature on the recombinant expression of agarases from 2012 to the present. Agarase genes originated from 19 genera, including Agarivorans, Flammeovirga, Pseudoalteromonas, Gayadomonas, Catenovulum, Microbulbifer, Cellulophaga, Saccharophagus, Simiduia, and Vibrio. Of the 47 recombinant agarases, there were only two α-agarases, while the rest were β-agarases. All α-agarases produced agarotetraose, while β-agarases yielded many neoagarooligosaccharides ranging from neoagarobiose to neoagarododecaose. The optimum temperature ranged between 25 and 60℃, and the optimum pH ranged from 3.0 to 8.5. There were 14 agarases with an optimum temperature of 50℃ or higher, where agar is in sol state after melting. Artificial mutations, including manipulation of carbohydrate-binding modules (CBM), increased thermostability and simultaneously raised the optimum temperature and activity. Many hosts and secretion signals or riboswitches have been used for recombinant expression. In addition to gene recombination based on the amino acid sequence after agarase purification, recombinant expression of the putative agarase genes after genome sequencing and metagenome-derived agarases have been studied. This study is expected to be actively used in the application fields of agarase and agarase itself.

• Journal of Microbiology and Biotechnology
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• v.27 no.12
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• pp.2180-2189
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• 2017

Psychrophilic phytases suitable for aquaculture are rare. In this study, a phytase of the histidine acid phosphatase (HAP) family was identified in Morchella importuna, a psychrophilic mushroom. The phytase showed 38% identity with Aspergillus niger PhyB, which was the closest hit. The M. importuna phytase was overexpressed in Pichia pastoris, purified, and characterized. The phytase had an optimum temperature at $25^{\circ}C$, which is the lowest among all the known phytases to our best knowledge. The optimum pH (6.5) is higher than most of the known HAP phytases, which is fit for the weak acidic condition in fish gut. At the optimum pH and temperature, MiPhyA showed the maximum activity level ($2,384.6{\pm}90.4{\mu}mol{\cdot}min^{-1}{\cdot}mg^{-1}$, suggesting that the enzyme possesses a higher activity level over many known phytases at low temperatures. The phytate-degrading efficacy was tested on three common feed materials (soybean meal/rapeseed meal/corn meal) and was compared with the well-known phytases of Escherichia coli and A. niger. When using the same amount of activity units, MiPhyA could yield at least $3{\times}$ more inorganic phosphate than the two reference phytases. When using the same weight of protein, MiPhyA could yield at least $5{\times}$ more inorganic phosphate than the other two. Since it could degrade phytate in feed materials efficiently under low temperature and weak acidic conditions, which are common for aquacultural application, MiPhyA might be a promising candidate as a feed additive enzyme.