• Journal of Microbiology and Biotechnology
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• v.21 no.10
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• pp.1053-1056
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• 2011

Optimal conditions for a high cell density fermentation were investigated in a recombinant Escherichia coli producing salmosin, a platelet aggregation inhibitor. The optimized carbon and nitrogen sources were glycerol 10 g/l, yeast extract 30 g/l, and bacto-tryptone 10 g/l, yielding the dry cell weight (DCW) of 10.61 g/l in a 500 ml flask culture. The late-stage induction with 1% L-arabinose in a 5 l jar fermentor showed the highest DCW of 65.70 g/l after 27 h of the fed-batch fermentation. Around 2,200 mg/l of the protein was expressed as an inclusion body that was then refolded to obtain the active salmosin of 96 mg/l. We also confirmed the inhibitory activity against platelet aggregation of the active salmosin from the high cell density fermentation.

• Journal of the Korea Organic Resources Recycling Association
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• v.9 no.4
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• pp.99-104
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• 2001

The influence of agitation speed on the yeast growth was investigated in the production of probiotic feed from pulverized liquified food wastes by aerobic fermentation. A yeast Kluyvermyces marxianus was selected through a preliminary screening. The yeast was cultured by 2liter jar fermenter. in 10% solid(w/v) substrate of liquified food waste at $35^{\circ}C$ with each different agitation speed of 500, 900 and 1200 rpm. For the acceleration of enzyme excretion mixed culture with Aspergillus oryzae was also attempted and the results were compared to those of single culture. As results the viable cell number was increased by increasing agitation speed. But it showed highest value in 900rpm and then decreased in 1200rpm. The mixed culture increased amylase activity and growth rate, but did not seem to enhance the highest viable cell count in the final fermentation stage.

• The Korean Journal of Malacology
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• v.28 no.1
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• pp.55-64
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• 2012

Ultrastructural studies of germ cell development during spermatogenesis and taxonomic values in mature sperm morphology of Argopecten irradians irradians were investigated by transmission electron microscopic observations. In the early stage of spermatid during spermiogenesis, a few granules and proacrosomal granules are formed by the Golgi complex. In the late stage of spermatid during spermiogenesis, a proacrosomal vesicle becomes an acrosomal vesicle in the acrosome through spermiogenesis. The sperm is approximately $ 45-48{\mu}m$ in length including a jar-shaped sperm nucleus (about $1.45{\mu}m$ long), an acrosome (about $0.34{\mu}m$ long) and tail flagellum. The axoneme of the sperm tail shows a 9+2 structure. As one of common characteristics of mature sperm morphologies in Pectinidae species in subclass Pteriomorphia, mature spermatozoon consists of the cone-shaped acrosomal vesicle and subacrosomal material on the invaginated jar-shaped nucleus. The acrosomal vesicle of this species is composed of electron high dense opaque part (material) from the base to the tip, as have seen in the species in the subclass Pteriomorphia. Exceptionally, five mitochondria are found in the sperm midpiece of this species, unlike four in most species of Pectinidae in subclass Pteriomorphia. However, the acrosomal vesicle of spermatozoa of A. irradians irradians resemble to those of other investigated Pectinidae species in subclass Pteriomorphia. Therefore, we can use sperm morphology as a tool in the resolution of taxonomic relationships within the Pectinidae species. These morphological charateristics of acrosomal vesicle belong to the family Pectinidae in the subclass Pteriomorphia.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.1
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• pp.8-14
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• 2002

Quality variation of jar packing of Chanran-Jeotgal produced by improved process and conventional process were investigated during storage at 10, 20, and $30^{\circ}C$, respectively. The increasing rate of pH, volatile basic nitrogen (VBN), $CO_{2}$, and viable cell counts of Chanran-Jeotgal produced by improved process was slower than that of conventional process at all storage temperature. Also the result of sensory evaluation indicate that the production of Changran-Jeotgal by improved process may extend the shelf·life of jar packing Chanuan-Jeotgal. From above results, relationship between quality parameters was concluded. In case of Changran-Jeotgal in a jar, pressure, pH, L-value, VBN and sensory score were highly correlated. Therefore, these parameters are expected to use as shelf-life indication.

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2001.05b
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• pp.121-125
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• 2001

For the probiotic feed production, aerobic liquid fermentation of pulverized food wastes was attempted with a yeast Kluyveromyces marxianus. After grinding finely, optimal fermentation conditions of the substrate was investigated by shaking culture. The most active growth of the yeast was shown at solid content of 10%. The proper addition of urea(0.5g/l), o-phosphate(0.4g/l), molasses(4g/l), and yeast extract (1g/1) increased cell growth rate and viable cell count. For optimizing, the nutrients were all added to substrate and fermentation was carried in 2 litre jar fermenter. For the stimulation of hydrolyzing enzyme excretion, mixed culture with Aspersillus oryzae was also conducted. In 12 hours of fermentation, viable cell count of the yeast Kluyveromyces marxianus amounted to the number of 1.4 $\times$10$^{10}$ /1 in the culture medium.

• Microbiology and Biotechnology Letters
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• v.10 no.2
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• pp.95-100
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• 1982

Torulopsis candida FRI YA-15, a selected yeast, was cultivated in alcohol distiller's waste-filtrate of dried sweet potato for microbial protein production and BOD reduction. The General composition of waste-filterate was BOD$_{5}$ 15700 ppm, COD 36800 ppm, reducing sugar 3300 ppm, total nitrogen 910 ppm, total solids 51800 ppm and ash 390 ppm. The pH of waste was 3.85. The yield to the medium of T. candida cultivated in shake-flask at $25^{\circ}C$ for 48 hrs was 3.38g/$\ell$ and effectiveness in reducing BOD$_{5}$ and COD of waste was 38.9% and 31.8%, respectively. In batch cultivation using 3 $\ell$-jar fermenter, maximum yield to the medium reached 3.2g/$\ell$after 28 hrs cultivation under the condition of temperature 35$^{\circ}C$, initial pH 4.0, aeration rate 2vvm, agitation speed 100rpm. Dry yeast was composed of crude protein 47.98% and ash 5.23%.

• Microbiology and Biotechnology Letters
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• v.17 no.6
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• pp.556-562
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• 1989

The bioconversion of mandarin orange peel press liquor to single cell protein (SCP) by two yeast strains, F-60, and C-7, which were isolated from mandarin orange peel was carried out and compared with that of using Candida utilis IFO 0598. Experiments were directed toward the high yield of biomass and high protein in cultures of the strains mentioned above. Candida utilis IFO 0598, F-60 and C-7 strains were cultivated at 3$0^{\circ}C$, pH 5.2 for 3 days in shaking flasks. The effects of some nutrients on cell growth were studied. Cell mass and protein content per cell mass were increased by addition of urea 1%, KH$_2$PO$_4$ 0.1% and MgSO$_4$ㆍ7$H_2O$ 0.05%, When the F-60 strain cultured under the optimal conditions, cell mass, growth yield and protein content were 41.2g/l, 53.9%, 59.7%, respectively. Cell mass was also increased up to 15% by modifying the fermentation condition on the bench type 20l jar fermentor. Crude fat content (10.3%) of dried C-7 cell was higher than those of C. utilis and F-60, 4.9% and 5.6% respectively. Total protein content of the F-60 strain was 59.7% per dry weight. And we compared their amino acid compositions with that of FAO provisional pattern. In the case of the F-60 strains, amino acid contents such as lysine, leucine and isoleucine were much higher than those of methionine, cystine and tryptophan.

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.211-214
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• 2000

Marine Microorganism strain 96CJ10356 produced extracellular polysaccharide (EPS-R) accompanied with cell growth. To improve the production of EPS-R, the effect of aeration rate was tested in a 5-liter jar fermentor with STN medium. The production of EPS-R was increased with aeration rate and after 72 hour cultivation, 12.20 g/l of EPS-R was obtained with an aeration rate of 1.5 vvm and the apparent viscosity was measured to be about 1000 cp with culture broth.

• Proceedings of the Korean Society of Life Science Conference
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• 2005.09a
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• pp.84-84
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• 2005

• Journal of Life Science
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• v.12 no.3
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• pp.242-249
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• 2002

The optimal culture conditions in 500$m\ell$ flask suture, 5$\ell$ jar fermenter and 2,000 $\ell$ large stale culture were investigated to maximize the production of antibiotic on Rhizoctonia solani AC4, the causal agent of vegetables damping-off, by the strain Bacillus ehimensis YJ-37. Starch (1.5%) as a carbon source, peptone (0.6%) as a nitrogen source and MgC1$_2$(0.15%) as a metal ion in the medium containing N $a_2$HP $O_4$(0.3%) showed the highest production of the antibiotic(s) in a rotary shake (200 rpm). Optimal initial pH of the culture medium, culture temperature and culture time for the antibiotic(s) production were pH 8.0, 32$^{\circ}C$ and 54hrs, respertively. Under the optimal renditions in flask culture, cell growth and antifungal activity (clear zone size) were 1.42 $\times$ 10$^{8}$ cfu/$m\ell$ (21g-DCW/ $\ell$) and 13.9 mm, respectively. In 5 $\ell$ jar fermenter (medium 3 $\ell$), optimal air flow, agitation speed and culture time for the antibiotic(s) production were 2 vvm, 200 rpm and 48hrs, respectively. Under the optimal conditions in 5 $\ell$ jar fermenter, tell growth and antifungal activity were 2.06 $\times$ 10$^{8}$ cfu/$m\ell$ (30g-DCW/ $\ell$) and 13.4 mm, respectively. Under the culture conditions of air flow (30 vvm) and agitation speed (200 rpm) at 32$^{\circ}C$ for 10 days in 2,000 $\ell$ large scale culture (medium 1,800 $\ell$, pH 8.0), cell growth and antifungal activity were 0.81$\times$10$^{8}$ cfu/$m\ell$ (12g-DCW/ $\ell$) and 8.6 mm, respectively.