• Korean Chemical Engineering Research
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• v.54 no.1
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• pp.140-144
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• 2016

In this study, the physical factors for amylase production by Arthrobacter sp. were optimized using response surface methodology(RSM). Antarctic microorganism Arthrobacter sp. PAMC 27388 was obtained from the Polar and Alpine Microbial Collection(PAMC) at the Korea Polar Research Institute. This microorganism was confirmed for the excretion of amylase with Lugol's solution. The amylase activity was after flask culture was as low as 1.66 mU/L before optimization. The physical factors including the inoculum volume, the initial culture pH, and the medium volume were chosen to be optimized for the enhanced amylase production. The calculated results using RSM indicate that the optimal physical factors were 2.49 mL inoculum volume, 6.85 pH and 42.87 mL medium volume with a predicted amylase production of 2.84 mU/L. The experimentally obtained amylase activity was 2.50 mU/L, which was a 150% increase compared to the level before optimization.

• KSBB Journal
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• v.22 no.5
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• pp.288-296
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• 2007

Monascus pilosus (KCCM 60160) in submerged culture was optimized based on culture medium and fermentation conditions. Monacolin-K (Iovastatin), one of the cholesterol lowing-agent which was produced by Monascus pilosus may maintain a healthy lipid level by inhibiting the biosynthesis of cholesterol. Plackett-Burman design and response surface method were employed to study the culture medium for the desirable monacolin-K production. As a result of experimental designs, optimized production medium components and concentrations (g/L) were determined on soluble starch 96, malt extract 44.5, beef extract 30.23, yeast extract 15, $(NH_4)_2SO_4$ 4.03, $Na_2HPO_4{\cdot}12H_2O$ 0.5, L-Histidine 3.0, $KHSO_4$ 1.0, respectively. Monacolin-K production was improved about 3 times in comparison with shake flask fermentation of the basic production medium. The effect of agitation speed (300, 350, 400 and 450 rpm) on the monacolin-K production were also observed in a batch fermenter. Maximum monacolin-K production with the basic production medium was 68 mg/L when agitation speed was 500 rpm. And it was found that all spherical pellets (average diameter of $1.0{\sim}1.5mm$) were dominant during fermentation. Based on the results, the maximum production of 185 mg/L of monacolin-K with the optimized production medium was obtained at pH (controlled) 6.5, agitation rate 400 rpm, aeration rate 1 vvm, and inoculum size 3%.

• Microbiology and Biotechnology Letters
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• v.31 no.1
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• pp.46-50
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• 2003

Lactococcus lactis SA72 from Jeot-gal (Korean traditional fermented fish foods) produces lacticin SA72. The influence of several parameters on the fermentative production of lacticin SA72 by Lactococcus lactis SA72 was studied. MRS medium among several media was selected for enhanced bacteriocin production. The mean growth rate and bacteriocin productivity of L. lactis SA72 increased as the initial pH of the media increases. The highest lacticin SA72 activity was detected 3,200 AU/ml at pH 6.0, $32^{\circ}C$, and 1% (inoculum size, v/v) in the jar fermenter. Enhanced production of lacticin SA72 was investigated by a fed-batch cultivation with the intermittent feeding of the concentrated glucose solution. Under the optimized conditions, lacticin SA72 activity finally reached to 6,400 AU/ml.

• Bioindustry News
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• v.10 no.1
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• pp.10-14
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• 1997

• Journal of Life Science
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• v.26 no.5
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• pp.571-583
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• 2016

Biogenic amines are produced primarily by microorganisms found in fermented foods and are often implicated in poisoning incidents in humans. In this study, 620 strains of microorganisms were isolated from traditional Korean fermented food in Sunchang in order to screen for non-biogenicamine-producing microorganisms present in these foods. One strain was identified and named Bacillus subtilis SCJ1, by using 16S rRNA sequencing and biochemical characterization. We investigated the cell growth of this organism in order to understand its potential for industrial application. To this end, we optimized the culture medium constituents by using the response surface methodology. The Plackett-Burman experimental design was used for screening of the medium constituents, such as molasses, yeast extract and peptone, for improving cell growth. In order to determine the optimal concentration of each constituent, we used a central composite design. Consequently, the optimized concentrations of molasses, yeast extract and peptone were predicted to be 27.5 g/l, 7.5 g/l and 17.5 g/l, respectively. By model verification, we confirmed that a 1.49-fold increase in dry cell weight compared to the basal medium-from 1.32 g/l, to 1.9722 g/l-was achieved.

• Korean Chemical Engineering Research
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• v.52 no.6
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• pp.834-839
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• 2014

This study was conducted to optimize the medium composition for carotenoid production in Arthrobacter sp. PAMC 25486 through response surface methodology (RSM). Using a Placket-Burman design, from which yeast extract, $MgSO_4$ and dextrose were identified as the significant factors affecting carotenoids production. RSM studies for carotenoids production by Arthrobacter sp. PAMC 25486 have been carried out for three parameters of yeast extract, $MgSO_4$ and dextrose concentrations. These significant factors were optimized by experiments and RSM, as 1 g/L yeast extract, 0.0879 g/L $MgSO_4$ and 1 g/L dextrose. The experimentally obtained concentration of carotenoid was 288 mg/L, and it became 2-fold increase on concentration before optimization.

• Korean Chemical Engineering Research
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• v.55 no.1
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• pp.74-79
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• 2017

In this study, the optimization of several factors for Chlorella saccharophila cultivation was investigated. The studied factors were medium type, culture type, inoculum size, sugar/nitrogen source type and concentrations. As a result, the optimized conditions for C. saccharophila cultivation were found to be the best at 3% (v/v) inoculum, 30 g/L glucose and 0.95 g/L $NaNO_3$ under mixotrophic culture. Under the optimized condition, the content of oil was high at 12 day, whereas, the amount of biomass and chlorophyll were high at 10 day.

• Microbiology and Biotechnology Letters
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• v.48 no.3
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• pp.337-343
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• 2020

In this study, the medium optimization for cell growth and metabolite formation of Haematococcus sp. under mixotrophic cultivation was investigated. As a result, modified MS medium was selected as the basal medium; glucose was selected as the carbon source, with an optimum concentration of 10 g/l, and potassium nitrate was chosen as the nitrogen source, with an optimum concentration of 1.9 g/l. Under optimum conditions, Haematococcus sp. demonstrated an increase in biomass concentration from 0.18 gDW/l to 5.58 gDW/l in 14 days, after which there was a 31-fold increase in its growth. At the same time, the concentrations of chlorophyll and carotenoids were 172.16 mg/l and 42.33 mg/l, respectively. This work will contribute to the basic data for mass cultivation of microalgae.

• Korean Journal of Food Science and Technology
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• v.21 no.3
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• pp.399-403
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• 1989

Studies were made to optimize the meida composition and cultural conditions for the mycelial growth of Agrocybe cylindracea. Media composition for optimal growth was found to be starch 20.0g/l, bacto-soytone 4.0g/l. The media supplemented with $KH_2PO_4\;0.46g/l,\;K_2HPO_4\;1.0g/l,\;MgSO_47H_2O\;0.5g/l$ supported mycelial growth better than the media without mineral salts. Optimum temperature and pH for the growth was $28^{\circ}C$, and 6.0 respectively. Temperature range for the mycelial growth appeared to be $10-35^{\circ}C$ and the mycelium evidently lost the vitality at $40^{\circ}C$.

• KSBB Journal
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• v.23 no.1
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• pp.54-58
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• 2008

Hydrogen is considered as an energy source for the future due to its environmentally friendly use in fuel cells. A promising way is the biological production of hydrogen by fermentation. In this study, the optimization of medium conditions which maximize hydrogen production from Enterobacter aerogenes KCCM 40146 were determined. As a result, the maximum attainable cumulative volume of hydrogen was 431 $m{\ell}$ under the conditions of 0.5M potassium phosphate buffer, pH 6.5 medium containing 30 g/L glucose. The best nitrogen sources were peptone and tryptone for the cell growth as well as hydrogen production. The control of cell growth rate was found to be a important experimental parameter for effective hydrogen production