• The Korean Journal of Mycology
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• v.9 no.3
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• pp.117-122
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• 1981

A tunnel system of mushroom cultivation was designed to compare with the conventional cultivation method in Korea. The bed and air temperature during the phase II the tunnel system was more stably controlled than in the conventional house. The indipensable energy was much saved in the tunnel system than in the conventional method, as this system did not require additional heat supply in the phase II. Compost fermented in the tunnel was proved to contain higher total nitrogen and moisture than compost in the conventional house. Residual ammonia content of compost fermented in the tunnel did not exceed 300ppm. Mushlroom mycelial growth in the tunnel was as good as in conventional house. The tunnel system did not require additional heat supply during mycelial growth period. Mushroom yield and quality from the tunnel system was 5 per cent higher and better than that of the conventional method.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.4
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• pp.549-555
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• 1997

Twenty species of lactic acid bacteria were isolated from Kimchi. Six species were identified as Lactobacillus sake, ten species as Leuconostoc mesenteroides and four species as Lactobacillus plantarum. The ability of these isolates to deplete nitrite during growth at 15, 20, 25 and 3$0^{\circ}C$ in MRS broth containing 250$\mu\textrm{g}$/$m\ell$ of nitrite was examined. Depletion of nitrite was high as the order of L. plantarum, L. sake and L. mesenteroides at all temperature tested, and the depletion activity was increased as the increase of growth temperatures. Especially, almost all of nitrites were utilized by L. plantarum during growth at all temperature ranges tested. L. plantarum and L. sake required induction periods for adapting to nitrite, but L. plantarum was remarkably depleted nitrite after two days of growth at 15$^{\circ}C$ and one day at 2$0^{\circ}C$, L. sake after one day of growth at both temperatures. Whereas, L. mesentero-ides did not require those periods at all temperature ranges tested.

• Journal of agriculture & life science
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• v.45 no.6
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• pp.73-80
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• 2011

To investigate the characteristics of plant growth and flower quality of gerbera 'Sunny Lemon' by amount of nutrient solution, young seedling plants, 'Sunny Lemon' were transplanted to rock-wool and medium of peat moss and perlite mixed with 1 to 2 and they were acclimatized in greenhouse during about 1 month. Nutrient solution supplied to the plants is sonneveld solution of 1/2 concentration and treatments launched June 24, 2010 when average plant height was $20{\pm}1cm$. Nutrient contents as a standard for starting point of irrigation by time domain reflectometry (TDR) were determined with 60-65%, 70-75%, and 80-85%. Results of growth during vegetative growth, plant height, leaf width and leaf number increased by 10% in rockwool, but they were not significantly different. As for plant growth depending on nutrient content, 80-85% treatment showed the highest values. Leaf number increased by 60%, and leaf width and plant height had a about 40% increase than initial growth. Effectiveness for flower quality, yield and days to flowering were superior when nutrient content of media was higher than in the others. Especially, average days to flowering in 80-85% content was advanced by 7-10 days compared to the day in 60-65% treatment. The total amount of nutrient supply per plant was higher in mixed medium than in rockwool, but change patterns of EC and pH were enhanced in rockwool. Based on our results, we recommended that growth, cut flower, and yield of gerbera 'Sunny Lemon' were more effective when nutrient content of mixed medium was maintained at 80-85%.

• KSBB Journal
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• v.15 no.5
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• pp.482-488
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• 2000

The Fab fraction of PDC-E2 specific human monoclonal antibody was produced using recombinant E. coli, and the effects of glucose and acetate were investigated to develop an optimal strategy for recombinant human antibody production. Higher glucose concentration in the culture media resulted inn higher cell growth and glucose consumption rate, which in turn resulted in an increased acetate production rate. When glucose was depleted, cells began to consume acetate as an energy source, and this consumption rate depended on the glucose concentration. When the residual glucose concentration was high, the accumulation of acetate was accelerated due to an increase in the acetate production rate and a decrease in the acetate consumption rate. Futhermore, it was found that a high accumulation of acetate, accompanied by a high glucose concentration, inhibited human antibody formation; the critical acetate concentration was $0.6g/\ell$. During production, a high glucose concentration enhanced cell growth, but inhibited antibody formation due to catabolic repression. Therefore, it is important to keep the concentration of both glucose and acetate as low as possible to increase antibody production after induction. Accordingly, it is important to accurately control the concentration of glucose and acetate in the culture media to obtain high cell densities and high productivity levels of recombinant human antibody.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.374-377
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• 2001

On the basis of high-osmotic tolerance and xylitol productivity, it was isolated a novel strain from soil of rice field. An isolated strain was tentatively designated as Candida sp. HY200, deduced from the systematic approaches of bacterial identification by Biolog $Microlog^{TM}$ and, revealed an interesting ability of flocculation during the cultivation. With respect to the osmotic-tolerance and flocculation ability, experiment was carried out to investigate the production of xylitol in high xylose concentration. When xylose concentration was 260 g/L, it was obtained 205 g/L xylitol with 79% of yield and 2.14 g/L ${\cdot}$ h of productivity Consequently, We convinced that Candida sp. HY200 stands a very favorable comparison with C. tropicalis.

• Food Science and Preservation
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• v.31 no.1
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• pp.161-172
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• 2024

This study investigated the anti-obesity effects of lactic acid bacteria ferments cultured in industrial medium with ethanol extract of ramie leaf (Boehmeria nivea L.). On the 4th day of fermentation, the maximum live cell counts were 8.75-8.85 log CFU/mL, pH was 3.74-3.79, and total acidity was 2.07-2.19%. The fermentation of lactic acid bacteria on the fourth day resulted in the amount of lactic acid reaching 1,676.03-1,910.12 mg%. The lipase inhibitory activities of Lactiplantibacillus plantarum (L. plantarum) JBLAB0101 (FRLPLA) and Lactobacillus rhamnosus GG (LGG, (FRLLGG)) ferments were 30.10%, and 25.63%, respectively, at a concentration of 0.5 mg/mL. The lipid accumulation, leptin production, PPAR-γ and SREBP-1c mRNA levels were decreased to 37.54%, 54.64%, 24.18%, and 31.32%, respectively, at 200 ㎍/mL concentration of FRLPLA. These results suggest that anti-obesity effect could be increased by lactic acid bacteria in industrial medium with extract of ramie leaf.

• Korean Journal of Food Science and Technology
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• v.28 no.4
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• pp.756-761
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• 1996

Influence of acetic acid on xylitol production from xylose using Candida parapsilosis KFCC 10875 was investigated at the different concentrations of acetic acid. Acetic acid was totally consumed below 1.0 g/l of its concentration, whereas partially consumed above 3.0 g/l and remained in the medium during xylitol fermentation. Cell growth, xylose consumption, and xylitol production decreased when acetic acid concentration was increased. Specific growth rate of cell and specific consumption rate of xylose also decreased with increasing the concentration of acetic acid. However, the xylitol yield from xylose and specific production rate of xylitol were maximum at 1.0 g/l of acetic acid. The inhibitory effect of acetic acid on xylitol fermentation increased when pH was decreased.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.34 no.1
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• pp.89-94
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• 2010

Patterning bacteria and cells on substrates has potential applications in molecular biology, antimicrobial drug screening, environmental monitoring and tissue engineering. We developed a technique to deposit two-dimensional array of bacterial cells onto an agar plate by modifying commercially available thermal inkjet printers. The concentration of the bacterial solution in the cartridge was carefully determined to ensure a single cell suspension in a droplet ejected from a nozzle. We measured quantitatively the effects of the bacterial concentration and the agar concentration on patterning performance. Bacterial patterning by inkjet printer is a low-cost and versatile technique which may replace the existing sophisticated methods.

• KSBB Journal
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• v.4 no.3
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• pp.259-265
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• 1989

In a batch fermentation process using carrot cell suspension culture, the effect of initial concentration of limiting nutrients(glucose and phosphate) on the specific growth rate and cell yield was investigated. The period of exponential growth is about 2 days and the consumption of glucose and phosphate in culture medium was very small when the initial concentrations of glucose and phosphate are 1.49g/1 ~ 3.01g/l and 0.08 ~ 0.32mM respectively. The specific growth rate of cells ranged from TEX>$0.15\;day^{-1}$ to $0.3\;day^{-1}$ irregularly. And the ratio of the initial concentration of glucose to phosphate did not affect the specific growth rate and the cell yield. The increase on cells had linear relationship with the consumption of limiting nutrients. Therefore, the increase of cells was found to be more influenced by the concentration of glucose than that of phosphate.

• Korean Journal of Food Science and Technology
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• v.42 no.3
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• pp.355-360
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• 2010

Vibrio parahaemolyticus (V. parahaemolyticus), which is commonly found in raw seafood, causes gastroenteritis in humans. Rapid and effective methods have been developed as culture methods require up to 5-7 days. In this study, real-time PCR was compared with the standard culture method for detecting V. parahaemolyticus in seafood and radish sprout samples. Five hundred grams of the samples were artificially contaminated with V. parahaemolyticus then divided into 20 samples. The samples were incubated in alkaline peptone water and then streaked onto thiosulfate-citrate-bile saltssucrose agar. Biochemical tests for suspicious colonies were performed using the API 20NE strip. In parallel, real-time PCR was performed targeting the toxR gene using the enrichment broth. The real-time PCR was sensitive in discriminating V. parahaemolyticus from other foodborne pathogens. The detection limit of the real-time PCR was $10^3\;CFU/mL$ in phosphate-buffered saline. Although the real-time PCR detected more positive samples (76 out of 180, 42%) than the culture method (66 out of 180, 37%), there was no significant statistical difference (p>0.05) between the two methods. In conclusion, real-time PCR assays could be an alternative to the standard culture method for detecting V. parahaemolyticus in seafood and radish sprouts, which has many advantages in terms of detection time, labor, and sensitivity.