• Korean Journal of Animal Reproduction
• /
• v.22 no.1
• /
• pp.43-50
• /
• 1998

The effect of oxygen tension on embryonic development in co-culture was evaluated from the standpoint of the reduction of dissolved oxygen concentration by the oxygen consumption of feeder cells. Three co-culture systems using bovine oviductal epitherial cells (BOEC), African green monkey kidney cells (Vero cells) or buffalo rat liver cells (BRLC) have been compared in terms of development of bovine embryos derived from oocytes matured and fertilized in vitro. Among the co-cultured embryo, Vero cells su, pp.rted the highest developmental rate (29%) and the other two showed the similar rates. When the co-cultures were incubated in three different oxygen tension such as 5, 10, 20% oxygen atmosphere, embryos co-cultured with Vero cells at 10%-O2 resulted in the highest percentage of development. From the measurement of oxygen consumption of feeder cells, BRLC consumed 1.38　10-10 mg-O2/min/cell which was higher than 0.94　10-10 and 0.26　10-10mg-O2/min/cell for Vero cells and BOEC, respectively. Based on the oxygen consumption data, the phenomena of optimum oxygen tension required in embryo development in vitro has been analyzed, and we suggested that gas phase oxygen concentration, oxygen consumption rate of feeder cells and the number of feeder cells should be considered for the design of optimal co-culture system for effective fertilization of embryos in vitro.

• Microbiology and Biotechnology Letters
• /
• v.19 no.5
• /
• pp.521-535
• /
• 1991

A kinetic model incorporating cell morphology in cephalosporin C biosynthesis by Cephalosporium amemoniurn was developed. The double-substrate Double-substrate kinetic model was used to describe cell growth. Methionine controlled the rate of growth while glucose ultimately controlled the extent of growth. The changes in specific product formation rate were associated with morphologenesis, especially cell differentiation. To increase the productivity of cephalosporin C, the proposed model equations were applied to a fed-batch culture. The algorithm to optimize the fed-batch culture consists of two steps; cell growth was maximized in the growth phase and then cephalosporin C production was maximized in the production phase. The increase of about 33% in the cephalosporin C titre was obtained by the optimal feeding scheduling in comparison with that of batch culture.

• Reproductive and Developmental Biology
• /
• v.30 no.3
• /
• pp.163-167
• /
• 2006

The purpose of the present study was to establish culture conditions for the in vitro study of the neonatal piglet Sertoli cell. Isolation for the culture of Sertoli cell was established using collagenase and pancreatin digestion of testicular tissues. The effects of various culture media, fetal bovine serum(FBS), follicular stimulating hormone(FSH), epidermal growth factor(EGF) and insulin-transferrin-sodium selenite(ITS) on growth of neonatal piglet Sertoli cells were investigated. The mitogenic effects of Dulbecco's modified Eagle's medium+Ham's F-12 medium was higher than other media used in this experiment. The addition of 1% FBS in cultures was necessary for attachment of Sertoli cell clusters. However, except FBS and EGF, FSH and ITS did not stimulate Sertoli cell proliferation. When Sertoli cells isolated from neonatal piglets were cultured in Dulbecco's modified Eagle's medium+Ham's F-12 medium supplemented with 1% FBS, FSH EGF and ITS, the yield and plating efficiency of Sertoli cells were largely increased. Confluency of Sertoli cells was reached as early as 4 days of culture. The method described here reduces or eliminates many of the drawbacks of the conventional procedures used to isolate and culture of Sertoli cells, thus providing a useful tool in studies of growth kinetics and regulation of cell proliferation in vitro.

• Korean Journal of Plant Resources
• /
• v.21 no.6
• /
• pp.444-448
• /
• 2008

An adventitious root formation protocol from Smilax china L. was established for in vitro production of dioscin, a steroidal saponin having various bioactivities such as anticancer, antifungal, antiviral, and antiobesity. Optimal medium for root initiation from leaf explant was MS medium containing $30\;g{\cdot}L^{-1}$ of sucrose supplemented with $1.0\;mg{\cdot}L^{-1}$ kinetin + $2.0\;mg{\cdot}L^{-1}$ NAA. The induction of adventitious roots from in vitro initiated root segments was most favorable to MS liquid medium with $0.1\;mg{\cdot}L^{-1}$ kinetin + $2.0\;mg{\cdot}L^{-1}$ NAA. Among the 20 different adventitious roots originated from different plants, strain No. 10 was selected based on production ability of dioscin, and its stability through the successive suspension culture. The maximum growth stage of adventitious roots was noticed at 5 weeks after subculture while that of dioscin production in the adventitious root was at 7 weeks after subculture in suspension culture system. These results provide that suspension culture of adventitious roots of Smilax china L. have a potential for in vitro mass production of dioscin.

• 한국생물공학회:학술대회논문집
• /
• 2005.04a
• /
• pp.124-128
• /
• 2005

This studies were carried out to investigate optimal conditions for Lactic acid bacteria growth, which was grown in a batch fermenter. The optimal temperature was $30^{\circ}C$, optimal pH was 6.5 and agitation speed was 100rpm and didn't supply the air. Used media compositions were yeast extract 5g/L, peptone 10g/L, sugar 20g/L, beef extract 10g/L, tween 80 1ml/L, ammonium citrate 2g/L, sodium acetate 5g/L, magnesium sulfate 0.1g/L, manganese sulfate 0.05g/L, dipotassium phosphate 2g/L. These results would be useful for enhancing lactic acid bacteria concentration.

• Microbiology and Biotechnology Letters
• /
• v.37 no.1
• /
• pp.85-89
• /
• 2009

For the purpose of the methodological development to convert the food wastes into resources, we have attempted to culture the mushroom hypha, Pleurotus ostreatus. The food-wastes were mixed with distilled water, and the mixture was autoclaved to produce fluid, which was centrifugated and used as the growth media. Concentrations of the food wastes extracts were prepared with 10, 20, 30, 40, and 50%(W/V), and the initial pH were set variously with 4, 5, 6, and 7. These were cultured for 9 days at the temperature of $25^{\circ}C$ and the rotation rate of 120 rpm. The result is that the fluid form of the mushroom hypha have been grown best at the concentration of 30% and the optimal pH was 5 and 6.

• Microbiology and Biotechnology Letters
• /
• v.23 no.6
• /
• pp.647-651
• /
• 1995

A tylosin-hyperproductive mutant of S. fradiae MNU20 was isolated among 3500 strains obtaincd from either MNNG- or UV-treated Streptomyces fradiae NRRL2702. The composition of optimal medium for tylosin production was formulated as followed as: 4 g soluble starch, 1 g glucose, 1 g corn steep liquor, 7.5 ml soy bean oil, 0.2 g KH$_{2}$PO$_{4}$, 1 g Na$_{2}$S$_{2}$O$_{3}$$\cdot $5H$_{2}$O, 2 g CaCO$_{3}$, 2 g NaCl, 0.001 g CoCl$_{2}$$\cdot $6H$_{2}$O in 1 liter of distilled water. With the optimal medium, S. fradiae MNU20 was able to produce 159 mg tylosin (g biomass)$^{-1}$, indicating that tylosin productivity of Streptomyces fradiae NRRL2702 was increased 14 times higher by mutation. When the effect of valine, succinate, and natural zeolite on tylosin production was investigated by using the optimal medium, these substances essentially enhanced tylosin production and their addition time during culture period appeared to be critical for the increase of tylosin production.

• Environmental Engineering Research
• /
• v.20 no.2
• /
• pp.121-125
• /
• 2015

Biohydrogen production from food waste via dark fermentation was conducted by using mixed culture under various environmental conditions (initial pH, initial F/M ratio, initial ferrous iron ($Fe^{2+}$), and temperature condition) in batch reactor. The results revealed that the maximum hydrogen yield of $46.19mL\;H_2/g\;COD_{add}$ was achieved at the optimal conditions (initial pH 8.0, initial F/M ratio 4.0, initial iron concentration 100 mg $FeSO_4/L$ and thermophilic condition ($55{\pm}1^{\circ}C$)). Furthermore, major volatile fatty acid (VFA) productions of butyrate (765.66 mg/L) and acetate (324.69 mg/L) were detected and COD removal efficiency was detected at 66.00%. Therefore, these optimal conditions could be recommended to operate a system.

• Mycobiology
• /
• v.37 no.2
• /
• pp.103-108
• /
• 2009

The principal objective of this study was to acquire basic data regarding the mycelial growth characteristics for the artificial cultivation of Coprinus comatus. 12 URP primers were employed to evaluate the genetic relationships of C. comatus, and the results were divided into three groups. Among six kinds of mushroom media, MYP medium was selected as the most favorable culture medium for C. comatus. The optimal temperature and pH ranges for the mycelial growth of C. comatus were $23{\sim}26^{\circ}C$ and pH 6${\sim}$8, respectively. The carbon and nitrogen sources for optimal mycelial growth were sucrose and tryptone, respectively.

• 한국생물공학회:학술대회논문집
• /
• 2005.04a
• /
• pp.144-144
• /
• 2005