• Applied Chemistry for Engineering
• /
• v.29 no.1
• /
• pp.1-9
• /
• 2018

Microalgae is considered as one of environmentally sustainable and potential feedstocks to produce biodiesels. However, recent studies on life cycle assessments (LCA) of microalgal buidiesels have shown that energy requirement is not small to produce biodiesel from microalgae, especially during cultivation stage. The costs for carbon sources, nutrients like nitrogen or phosphorous, and water for cultivation can contribute up to 80% of the total medium costs. In the present article, recent trends on the utilization of several promising nutrient sources such as municipal wastewaters, organic fertilizers, combustion exhaust emissions and organic solid wastes were reviewed, and the potential strategies to be used as substitutes of artificial culture media, especially for the biodiesel production, were discussed.

• Journal of Veterinary Clinics
• /
• v.7 no.2
• /
• pp.517-519
• /
• 1990

In vitro maturation and fertilization of oocytes collected from slaughtered bovine ovaries were investigated. Immature bovine extrafollicular oocytes were cultured for 24 hrs. in TCM 199 supplemented with fetal calf serum in a humidified CO$_2$ incubator. Fertilization in vitro was performed using frozen-awed bull semen which was treated by Ca Ionophore A23187. Fourty percentage of oocytes cultured had matured to the metaphase II ; There were-no effects of the concentration of fetal calf serum and of the addition of HEPES on the maturation rate. The mean proportions of in vitro fertilized eggs and of cleaved eggs were 23.1％ and 14.4％, respectively.

• Microbiology and Biotechnology Letters
• /
• v.18 no.4
• /
• pp.383-389
• /
• 1990

During the cultivation of Penkillium uerrmulosum in the media containing cellobiose octaacetate (COA), avicel, or KC-flock as an inducer and as a sole carbon source for 21 days, cellulolytic activity and SDS-PAGE pattern of proteins in the culture broth were investigated. Protein concentration and cellulolytic activity were highest in the COA medium. As cultivation period was increased, protein content and avicel hydrolytic activity of culture broth were increased as similar extent but neither $\beta$-glucosidase nor CMC hydrolytic activity was correlated to protein content. When crude proteins from the culture broth were separated on DEAE column by HPLC, distribution of avicel-hydrolytic activities were well correlated with that of major proteins. From those results it was suggested that three major proteins having 60 K, 68 K, and 76 K of Mr. were avicel-hydrolytic enzymes.

• Proceedings of the Korean Society of Food Hygiene and Safety Conference
• /
• 2004.05a
• /
• pp.224-228
• /
• 2004

2002년 8월부터 11월까지 전국 27개 지역에서 희나리 고추를 포함하고 있는 태양초 시료 40군을 수집하여 총 197주의 곰팡이를 분리하였다. 이 곰팡이들을 고체배지상에서의 번식속도, 분생포자의 모양 및 배양특성의 특성에 따라 6개의 group오로 나누었고 각 group에서 대표가 되는 30 균주를 임의로 선택하여 18S rRNA gene 염기서열을 분석하여 동정하였다. 희나리 곰팡이 중 에서 Colletotrichum 속 곰팡이가 66.5% (131/197)를 차지하여 가장 많이 분리되었고, 기타 Diaporthe phaseolorum var. sojae (28주, 14.2%), Alternaria alternata (17주, 8.6%), Botryosphaeria ribis (9주, 4.6%) Aspergillus oryzae var. oryzae (3주 1.5%) 및 Fusarium incarnatum (9주, 4.6%)이 동정되었다. 각 group에서 임의적으로 한 균주씩을 선택하여 현미에 배양한 뒤 쥐(rat)에 투여시험한 결과 A. alternata를 접종한 사료를 먹인 실험동물이 2주내에 모두 죽었으며 다른 곰팡이를 배양한 사료에는 특이한 영향이 없었다. A. alternata 곰팡이를 현미와 고추즙에 배양하여 주요 독소들을 분석한 결과 17주의 곰팡이 중 8주가 현미와 고추즙에서 많은 양 (현미: $488{\sim}1572\;{\mu}g/g$, 고추즙: $115{\sim}1050\;{\mu}g/g$)의 tenuazonic acid (TeA)를 생성하였다. alternariol(AOH)독소와 alternariol monomethyl ether (AME)는 현미에 배양했을 때만 흔적량 내지 소량씩이 관찰되었다. Alternaria 독소 중 altenuene는 현미와 고추즙 배지 모두에서 검출되지 않았다.

• Korean Journal of Food Science and Technology
• /
• v.13 no.4
• /
• pp.314-318
• /
• 1981

In order to improve the storage stability of spray and freeze dried red ginseng extract powder packed in a bottle, the water vapor permeability of Al-foil laminate paper used for cap closure and shelf life of those products on various storage temperatures and relative humidities were investigated. The thickness of the laminate paper was $93{\pm}3\:{\mu}m$ and its physical properties were equal to standard of ASTM (B-377-66) The absorption rate of the freeze dried powder was 2-6 times greater than that of the spray dried powder at $37^{\circ}C$. Therefore it was considered that the laminate could be used for cap closures for the spray dried powder but unsuitable for the freeze dried powder. The shelf life of the spray dried powder was longer than that of the freeze-dried powder at $37^{\circ}C$.

• Korean Journal of Plant Tissue Culture
• /
• v.21 no.2
• /
• pp.91-97
• /
• 1994

To improve the productivity of peroxidase (POD) of cell line SP-47 derived from cell suspension cultures of sweet potato (Ipomoea batatas (L) Lam.cv White Star), we optimized culture conditions including the composition and concentration of plant growth regulators and carbon source, and the cell inoculum size. When one g (fr wt) of cells was inoculated into 50 mL TL medium supplemented with l mg/L 2,4-D and 30g/L sucrose in 300 mL Erlenmeyer flask at 25$^{\circ}C$ in the dark (100rpm), the POD activity per g cell dry wt was maximized to be about 6,800 units after 25 days of subculture, which was about 30 times higher than that of intact roots of horseradish plants grown in the greenhouse, but the cell growth was maximum after 15 days of subculture. The protein content per g cell dry wt maintained almost plateau and after 25 days of subculture decreased as culture Proceeded further whereas the POD specific activity (unit/mg protein) was about two times higher after subculture and continuously increased from 12 days to the end of cultures (40 days). The POD isozyme patterns showed almost the same regardless of cell growth stage, but some acidic isozymes were slightly increased after 25 days of subculture. These results indicate that POD activity in suspension cultures of sweet potato is closely associated with cell growth and stresses derived from cell culture renditions and medium depletion. Due to its high POD activity the SPL47cell line seems to be suitable for the mass production of POD.

• Journal of Embryo Transfer
• /
• v.19 no.3
• /
• pp.275-282
• /
• 2004

This study was carried out to examine the effects of development media and those change on in vitro development (IVD) of porcine oocytes matured and fertilized in vitro. Putative embryos, which were matured in vitro in modified NCSU-23 (mNCSU-23) supplemented with 10％ porcine follicular fluid (pFF) and were fertilized in mTBM, were developed in vitro as the experimental scheme. The results are as follows. When porcine putative embryos were cultured in vitro in NCSU-23 or CZB/Pig-MEM, the percentage of oocytes cleaved was not different between two systems, but the percentage of blastocysts in NCSU-23 was significantly higher than in CZB/Pig-MEM (P<0.05). And when porcine putative embryos were cultured in vitro in NCSU-23 during 7 days with or without changing media at day 5, which was supplement with or without 10％ fetal bovine serum(FBS), the percentage of oocytes cleaved, blastocysts at day 6, and the cell number of ICM, TE and total of blastocysts at day 7 were not different among three treatments. As a result of this study, it is supposed that NCSU-23 be more favorable, to develop porcine embryos derived from IVM/IVF, than CZB/Pig-MEM, but that demonstration on the effects of changing medium with fresh one stand in need of the more experiments.

• Proceedings of the Korean Aquaculture Society Conference
• /
• 2003.10a
• /
• pp.23-23
• /
• 2003

김 붉은갯병은 김 엽체에 난균류 Pythium속의 Pythium porphyrae의 기생에 의해 발생되어 매년 김 양식에 큰 피해를 주는 매우 심각한 김 갯병중의 하나이다. 최근에는 이들 병해의 발생 및 억제를 위한 김 산처리제 (활성처리제) 남용에 따른 연안 양식어장의 생태계 파괴 및 김의 자연식품에 대한 이미지 훼손 등의 문제점이 대두되고 있다. 따라서 본 연구에서는 김 양식시 발생되는 붉은갯병의 병해를 억제하고자 활성처리제 처리시 고염분해수 처리를 병용함으로써 활성처리제의 사용을 최소화하면서 처리효과를 배가시키고자 하였다. 시험에 사용한 김 엽체는 2002년 10월에 전라남도 해남군 황산면 지선에서 채묘한 방사무늬김 (Porphyra yezoensis)을 육묘해 엽장 1cm 내외에서 냉동망을 제작하여 -2$0^{\circ}C$에 저장한 엽체를 자연해수 (약 27$\textperthousand$), 15$^{\circ}C$, 100$\mu$mol photon m$^{-2}$ s$^{-1}$, 광주기 9L : 15D의 배양조건하에서 15일간 배양한 엽장 3-4cm 정도의 것이었다. 활성처리제와 고염분해수처리제의 병용에 의한 붉은 갯병 억제효과는 붉은갯병 병원균의 유주자를 김 엽체에 감염시킨 후 27$\textperthousand$의 자연해수에 12일간 배양하면서 염분농도를 3-25%, 처리주기를 1-2회로 하여 각 시험구별 병해정도로 평가하였다. 고염분해수 처리에 의한 붉은갯병균 균사의 생장억제 효과는 김 엽체를 붉은갯병 병원균의 유주자로 감염시킨 다음 감염 12시간 후 염분농도를 3-25%로 처리한 후 27$\textperthousand$의 자연해수에 4일간 배양하면서 각 시험구별 배양시간에 따른 병원균 균사에 의한 김 엽체의 감염세포수로 평가하였다. 활성처리제와 고염분해수처리제의 병용이 김 엽체 생장에 미치는 영향은 건전한 김 엽체의 절편을 27$\textperthousand$의 자연해수에 배양하면서 시험구별로 활성처리와 고염분해수 (5, 10, 15, 20, 25%) 처리를 3일 간격으로 하면서 12일간 배양한 후 엽체의 엽면적 증가율로 평가하였다. 활성처리제와 고염분해수처리제의 병용에 의한 붉은갯병의 억제효과는 대조구 (활성처리 1회)와 비교해 주 2회의 활성처리구와 염분농도 20, 25% 처리구에서 병해 억제효과가 월등히 높았다. 고염분해수 처리에 의한 붉은갯병균 균사의 생장억제 효과는 염분농도 5, 10% 처리구의 경우 무처리구에 가까운 감염세포수를 보였으나, 염분농도 20, 25% 처리구의 경우 활성처리제 처리와 비슷한 감염세포수를 보여 뚜렷한 생장 억제효과를 나타냈다. 활성처리와 고염분해수 처리의 병용이 김 엽체 생장에 미치는 영향은 대조구 (활성처리 1회)의 3.4배 생장율과 활성처리와 염분농도 5-20%의 고염분해수 병용 처리구의 3.1-3.6배 생장율은 유의한 생장차이를 보이지 않았다 (P<0.05).

• Journal of Life Science
• /
• v.28 no.8
• /
• pp.969-976
• /
• 2018

In this study, transglucosidase (TG), an enzyme produced by Aspergillus niger, synthesized isomaltooligosaccharide from ${\alpha}-(1{\rightarrow}4)$ linked substrates. The highest TG-producing A. niger KCTC6913 was selected from six kinds of species, and optimized TG producing conditions were established. Five different carbon sources (potato starch, sweet potato starch, corn starch, wheat starch, and dextrin) and three different nitrogen sources (yeast extract, malt extract, and beef extract) were tested to establish the carbon and nitrogen sources favorable for TG production. Measurements of TG activity after an initial culture at pH 5.0 for 15 days revealed that potato starch and yeast extract, which are basic culture media, resulted in the highest TG activity. In addition, A. niger KCTC6913 increased TG production under aerobic conditions and a controlled carbon/nitrogen ratio. In conclusion, to evaluate TG activity in the established optimal medium, it is confirmed that the basal and potato dextrose broth medium were used as a control, and the highest TG production was measured, which was highlighted in the established optimal medium.

• Korean Journal of Food Science and Technology
• /
• v.22 no.4
• /
• pp.421-425
• /
• 1990

This study was carried out to compare lactic acid bacteria count of liquid type yogurts with various experimental conditions during shelf-life period. The conditions were media(BCP and Elliker agar), incubation conditions(aerobic and anaerobic), dilution waters(saline and phosphate buffer) and dilution methods(10 and 100 times). All of the samples were incubated at $37^{\circ}C$ for 72 hrs. In the case of counting L. acidophilus as a yogurt starter culture, there were differences on dilution waters and incubation conditions, but were no difference on media and dilution methods. In the case of counting L jugurti and mixed strain with L. acidophilus and L. casei, there were differences on media, incubation conditions and dilution waters, but was no difference on dilution methods. For L. casei in the yogurt, media and dilution methods were shown slightly different viable cell count but incubation conditions were not shown difference. In the case of counting L. bulgaricus, there were differences on media, incubation conditions and dilution methods, but was no difference on dilution waters. Therefore, the measurment of lactic acid bacteria count may be effective if preferred experimental conditions are selected for different types of strain.