• 생명과학회지
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• 제6권2호
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• pp.135-141
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• 1996

양식을 위한 먹이사료로서 가능성 있는 효모균주를 연구하였다. Kluyveromyces fragilis효모와 Candida utilis 효모의 최대 비증식 속도와 바이오매스 효율은 Saccharomyces cervisiae 효모에 비하여 굉장히 높은 값을 나타내었다. 따라서, 이 연구는 대량생산을 위하여, 플라스크 배양을 통한 이들 두 효모균들의 성장특성에 그 초점을 맞추었다. 5% 접종량을 가지고 실험한 결과, 가장 좋은 $\mu$$_{max}$ 와 OD$_{max}$ 값들은 K, fragilis는 2.5% fructose 배지에서, C. utilis는 2% YE배지에서 각각 얻었으며, 이 때의 이 값들은 K. fragilis는 0.73 hr$^{-1}$1 와 3.00을 C. uitilis는 0.59 hr$^{-1}$ 와 2.80으로 밝혀졌다. 또한, 아연과 염의 초기종도가 증가할수록 균성장에 있어서의 우도기는 증가하였으며, 접종량이 증가할수록 유도가는 감소하였다. 두 효모균은 3.5% 염농도에서 비교적 잘 자랄 수 있었으며, C. utilis 효모균만이 아연을 이용할 수 있었다.

• Asian-Australasian Journal of Animal Sciences
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• 제27권10호
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• pp.1443-1451
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• 2014

Increasing cost and scarcity of maize has stimulated the use of alternative feed sources (AFS) in the diets of cattle. In this study, we investigated the effects of partial or total replacement of maize on nutrient digestibility, growth performance, blood metabolites, and economics in Limousin crossbred feedlot cattle. Forty-five $Limousin{\times}Luxi$ crossbred bulls were randomly assigned to the three treatment groups, orthodox diet (OD; 45.0% maize), partial replacement diet (PRD; 15% maize, 67% AFS), total replacement diet (TRD; 0% maize, 100% AFS). The growth feeding trial lasted for 98 days. Dry matter intake (DMI) and average daily gain (ADG) were recorded. The digestion trial was carried out after the end of the growth trial. Total faeces and feed samples were measured daily. Digestibilities of dry matter (DM) and organic matter (OM), crude protein (CP), neutral detergent fiber (NDF) and acid detergent fiber (ADF) were calculated. After the feeding trial, blood metabolites were measured in 12 animals from each group. Initial and final body weights did not differ significantly among treatment groups (p>0.05). The ADG and DMI were 1.72 and 8.66, 1.60 and 9.10, and 1.40 and 9.11 kg/d for OD, PRD, and TRD, respectively. The PRD and TRD exhibited lower ADG (p<0.01) and higher DMI (p<0.01) than OD. The DMI (%body weight) was comparable between groups (p>0.5). Feed efficiency of PRD and TRD were lower than OD (p<0.01). The DM digestibility decreased with reduced level of maize (p = 0.10), OM digestibility was higher in OD (p<0.05), and CP, NDF and ADF digestibilities were similar for all groups (p>0.05). Blood urea nitrogen (mg/dL) in PRD and TRD was higher than OD (p<0.01), while other blood parameters did not differ significantly. Feed costs ($/head/d) were 1.49, 0.98, and 0.72 for OD, PRD, and TRD, respectively (p<0.01). Feed costs per kg gain ($) were significantly lower for PRD (0.63) and TRD (0.54) than OD (0.89; p<0.01). Overall profit ($/head) and daily profit ($/head/d) did not differ significantly between treatments (p>0.05), although TRD showed the highest economic benefits overall (p<0.01). While a traditional diet maximized the growth rate, partial or total replacement of dietary maize with AFS proved economically feasible due to their lower costs and comparable nutrient digestibilities of DM, CP, NDF, and ADF. Partial replacement may prove economically competitive in the current situation of China.

• 한국수산과학회지
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• 제51권3호
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• pp.328-331
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• 2018

We developed and subsequently characterized mouse monoclonal antibodies (MAbs) against nervous necrosis virus (NNV, RGNNV genotype). We established six hybridoma clones secreting MAbs against NNV antigen: 2B1, 2B11, 2C12, 13C1-1, 13C1-2 and 14D11. All six MAbs belonged to the IgG2a isotype with a kappa light chain and their reactivity recognized against the 41 kDa coat protein of NNV by Western blot analysis. The affinity constants of the six MAbs were measured by enzyme-linked immunosorbent assay (ELISA). All six MAbs reacted with two NNV isolates (SgNag05 and Gemunodo06), while no reactivity was observed with five know fish viruses, namely marine birnavirus, infectious pancreatic necrosis virus, viral hemorrhagic septicemia virus, hirame rhabdovirus, and infectious hematopoietic necrosis virus. Moreover, high ELISA optical density (OD) values (0.87-1.42) were observed in the brain tissues of NNV-infected sevenband grouper, while low OD values (less than 0.12) were recorded in the brain tissues of uninfected fish. These results suggest that these six MAbs are highly competent and useful for the detection of NNV with the RGNNV genotype.

• 한국식품저장유통학회지
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• 제9권4호
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• pp.425-428
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• 2002

Genus Monascus(M. pilosus and M purpureus)의 배지(Lin, SP, YM YE, GMIN, SMO, MY, GY, Nishikawa, sucrose, stock culture, Mizutani, modified Lit Toya 및 쌀배지)에 따른 균의 증식도와 색소생성량을 조사하였다. M. pilosus 및 M purpureus의 증식도가 높은 배지는 Mizutani 배지와 Lin 배지 였으며 3$0^{\circ}C$에서 10일간 배양하였을 때 생균체 무게는 각각 24.5~26.9 g/100 mL 및 15.9~17.2 g/100 mL이였고 M. pilosus의 성장률이 높았다. 색소생성량이 높은 배지는 두 균주 다같이 Lin 및 Mizutani 배지였으며 각각 흡광도는 1.2~1.6 및 0.8~l.0이었다. 균주 중에서는 M. pilosus에서 높았다.

• Journal of Microbiology and Biotechnology
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• 제5권4호
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• pp.224-228
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• 1995

Fed-batch fermentations were conducted to produce human lipocortin-I (LC1), a potential anti-inflammatory agent, from recombinant Sacchromyces cerevisiae carrying a galactose-inducible expression system. The cell growth, expression level of LC1, and the plasmid stability were investigated under various LC1 induction modes performed by three different galactose feeding strategies. Galactoe was fed to induce the expression of LCl from the beginning (initial induction) of culture or when the cell concentration reached 120 OD (mid-phase induction) or 300 OD (late induction). Among the three galactose-induction modes tested, the initial induction mode yielded the best result with respect to a final expression level of LC1. Fedbatch fermentation with initial induction mode produced LC1 at a conentration of 220 mg/l, which corresponded to 1.38- and 1.53-fold increases over those produced by mid-phase and late induction modes.

• 한국어병학회지
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• 제32권1호
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• pp.45-48
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• 2019

We developed and subsequently characterized mouse monoclonal antibodies (MAbs) against recombinant VP28 structural protein (rVP28) of white spot syndrome virus (WSSV). We established six hybridoma clones secreting MAbs against rVP28: 15A11, 20G6, 31H2, 34H6, 38D1 and 43A1. All six MAbs recognized the 25 kDa of protein in gill homogenates of WSSV-infected shrimp by western blot analysis, while no reactivity was observed in gill homogenates of normal shrimp. Moreover, high enzyme-linked immunosorbent assay (ELISA) optical density (OD) values (0.8-2.68) were observed in the hemolymphs from WSSV-infected shrimp, while low OD values (less than 0.24) were recorded in the hemolymphs from normal shrimp, by using these six MAbs produced in this study. These results suggest that these six MAbs are useful for the detection of WSSV.

• KSBB Journal
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• 제16권5호
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• pp.474-479
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• 2001

$_{L}$-Iysine 의 생산을 Corynebacterium glutamicum SH35을 이용하여 유가식 배양법과 연속 배양법으로 수행하였다. 유가시 배양에 의한 $_{L}$-Iysine 생산을 조사한 결과 최종 발효액 중의 lysine 농도는 129.2 g/L, lysine 수율 및 productivity는 가각 47%m 3.08g.$L^{-1}$.$h^{-1}$이였다. Single-stage 연속 배양에서 dilution rate에 따른 균의 생장 및 lysine 생산을 조사한 결과, critical diluation rate은 0.100 h$^{-1}$으로 이때 균체농동($OD_{610}$)은 67, lysine 농도는 44.0 g/L 그리고 lysine 수율 및 productivity 는 41%, 4.39 g.$L^{-1}$.$h^{-1}$이고 lysine 연속배양 시 최적의 dilution rate 이였다. 또한 lysine 생산을 위한 medium reservoir 내의 최적 탄소원 농도, 최적 질소원(ammonium sulfate) 농도 및 최적 pH는 각각 108 g/L, 25 g/L 및 6.9이었다. 유가식 배양법과 single-state 연속 배양법에 의한 lysine 생산에서, productivity 는 유가식 배양의 경우 3.08 g.$L^{-1}$.$h^{-1}$인 반면, 연속 배양에서는 4.39 g.$L^{-1}$.$h^{-1}$로 유가식 배양법에서보다 약 1.4배 정도 증가하였따. 연속 발효 공정을 통해 생산 역가의 향상은 있었으나, lysine 농도와 수율이 낮아 이에 대한 해결책으로 two-stage 연속 배양 방법을 수행하였다. 그 결과, 연속 배양 발효 수행보다 lysine 농도는 2배 정도 증가하였으며, lysine 수율은 46%로서 유가식 배양과 비슷한 정도로 얻어졌다. 이러한 실험 결과로 미루어 lysine 생산 역가 향상을 위한 방법으로 two-stage 연속배양의 산업적인 이용가능성이 있을 것으로 사료된다.

• Asian-Australasian Journal of Animal Sciences
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• 제21권3호
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• pp.392-403
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• 2008

Four ruminally fistulated Hanwoo steers were used to determine the effects of level and degradability of dietary protein on ruminal fermentation, blood metabolites and concentration of soluble non-ammonia nitrogen (SNAN) in ruminal (RD) and omasal digesta (OD). Experiments were conducted in a $4{\times}4$ Latin square design with a $2{\times}2$ factorial arrangement of treatments. Factors were protein supplements with two ruminal crude protein (CP) degradabilities, corn gluten meal (CGM) that was low in degradability (rumen-degraded protein (RDP), 23.4% CP) or soybean meal (SBM) that was high in degradability (RDP, 62.1% CP), and two feeding levels of CP (12.2 or 15.9% dry matter). Ruminal fermentation rates and plasma metabolite concentrations were determined from the RD collected at 2-h intervals and from the blood taken by jugular puncture, respectively. The SNAN fractions (free amino acid, peptide and soluble protein) in RD and OD collected at 2-h intervals were assessed by ninhydrin assay. Mean ruminal ammonia concentrations were 40.5, 74.8, 103.4 and 127.0 mg/L for low CGM, high CGM, low SBM and high SBM, respectively, with statistically significant differences (p<0.01 for CP level and p<0.001 for CP degradability). Blood urea nitrogen concentrations were increased by high CP level (p<0.001) but unaffected by CP degradability. There was a significant (p<0.05) interaction between level and degradability of CP on blood albumin concentrations. Albumin was decreased to a greater extent by increasing degradability of low CP diets (0.26 g/dl) compared with high CP diets (0.02 g/dl). Concentrations of each SNAN fraction in RD (p<0.01) and OD (p<0.05) for high CP diets were higher than those for low CP diets, except for peptides but concentrations of the sum of peptide and free amino acid in RD and OD were significantly higher (p<0.05) for high CP diets than for low CP diets. Soybean meal diets increased free amino acid and peptide concentrations in both RD (p<0.01) and OD (p<0.05) compared to CGM diets. High level and greater degradability of CP increased (p<0.001) mean concentrations of total SNAN in RD and OD. These results suggest that RDP contents, increased by higher level and degradability of dietary protein, may increase release of free amino acids, peptides and soluble proteins in the rumen and omasum from ruminal degradation and solubilization of dietary proteins. Because SNAN in OD indicates the terminal product of ruminal metabolism, increasing CP level and degradability appears to increase the amount of intestine-available nitrogen in the liquid phase.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2001년도 추계학술발표대회
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• pp.315-316
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• 2001

In this study various nutritional and environmental parameters such as, initial moisture content, pH. inoculum size, air rate, sample size and nutrient supplement that influence pigment production were evaluated in solid-state cultures. optimum initial moisture content and pH were determined to be 50% and 6.0, respectively. The supplement of the substrate with different carbon, nitrogen, and mineral source reveals a more inhibitive effect as the substrate concentration increase. optimum aeration rate was determined to be 2vvm in flask culture. The maximum amount of red pigment, 3500 OD/g dried fermented rice, was obtained in optimum conditions which is obtained in solid flask culture.

• KSBB Journal
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• 제13권3호
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• pp.268-271
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• 1998

Bacteriorhodopsin in the purple membrane (PM) of halobacteria has recently been attracting much attention to be used as a component of molecular electron device and optical computers. In order to increase the productivity of bacteriorhodopsin in high cell density cultures of Halobacterium halobium R1, an internal membrane cell-retention bioreactor system was employed. As a result, the production of cell mass at OD660 of 12 and of bacteriorhodopsin at 125-130 mg/L were obtained using the internal membrane bioreactor system at a dilution rate of 0.066 hr-1. The productivity achieved by the internal membrane system (0.7 mg/L$.$hr) was 3.5-fold higher than that obtained by the corresponding batch cultivations (0.2 mg/L$.$hr).