• 한국식품조리과학회지
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• 제10권3호
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• pp.284-290
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• 1994

To prepare soybean curds, the concentration of $CaCl_2,\;MgCl_2,\;CaSO_4$ and glucono-%{\delta}$-lactone fresh solution as coagulants were determined by transmittance of whey using spectrophotometer. The concentrations of four coagulants at which the transmittance had the highest value were chosen. Moisture content, yield and protein recovery of soybean curds prepared with four coagulants were investigated. The textural properties were examined by Instron Universal Testing Machine, and sensory evaluation was carried out. The microstructure of soybean curds was examined by SEM. Soybean curds obtained with $CaCl_2\;and\;MgCl_2$ were hard and coarse, and had roasted nutty taste, whereas those with $CaSO_4$ and GDL revealed very smooth, soft and uniform. Soybean curd prepared with GDL had the lowest acceptability because of sour taste. The texture and acceptability of soybean curds were influenced by the type of coagulant.

• Current Research on Agriculture and Life Sciences
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• 제22권
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• pp.49-56
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• 2004

Cellulolytic enzymes were prepared from alkaline resistant microorganisms which were newly screened from calcic soil. Characteristics of enzymes and enzymatic deinking efficiency of wastepaper were investigated. The results were summarized as fellows: 1. The recovery rate of crude enzyme was 93.7% in Bio-B and 57.4% in Bio-F. 2. The protein content in crude enzymes was lowest and the thermal stability of crude enzymes was highest in Bio-F. 3. The brightness gain of Bio-F deinked pulp was best in ONP and Bio-B deinked pulp was best in MOW. 4. The reject yield was increased with enzymatic deinking flotation process. 5. The residual ink area of paper was increased with enzymatic deinking and large size of ink particles were remained in paper.

• BMB Reports
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• 제37권4호
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• pp.408-415
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• 2004

The expression of the Paenibacillus sp. A11 cyclodextrinase (CDase) gene using the pUC 18 vector in Escherichia coli JM 109 resulted in the formation of an insoluble CDase protein in the cell debris in addition to a soluble CDase protein in the cytoplasm. Unlike the expression in Paenibacillus sp. A11, CDase was primarily observed in cytoplasm. However, by adding 0.5 M sorbitol as an osmolyte, the formation of insoluble CDase was prevented while a three-fold increase in cytoplasmic CDase activity was achieved after a 24 h-induction. The recombinant CDase protein was purified to approximately 14-fold with a 31% recovery to a specific activity of 141 units/mg protein by 40-60% ammonium sulfate precipitation, DEAE-Toyopearl 650 M, and Phenyl Sepharose CL-4B chromatography. It was homogeneous by non-denaturing and SDS-PAGE. The enzyme was a single polypeptide with a molecular weight of 80 kDa, as determined by gel filtration and SDS-PAGE. It showed the highest activity at pH 7.0 and $40^{\circ}C$. The catalytic efficiency ($k_{cat}/K_m$) values for $\alpha$-, $\beta$-, and $\gamma$-CD were $3.0{\times}10^5$, $8.8{\times}10^5$, and $5.5{\times}10^5\;M^{-1}\;min^{-1}$, respectively. The enzyme hydrolyzed CDs and linear maltooligosaccharides to yield maltose and glucose with less amounts of maltotriose and maltotetraose. The rates of hydrolysis for polysaccharides, soluble starch, and pullulan were very low. The cloned CDase was strongly inactivated by N-bromosuccinimide and diethylpyrocarbonate, but activated by dithiothreitol. A comparison of the biochemical properties of the CDases from Paenibacillus sp. A11 and E. coli transformant (pJK 555) indicates that they were almost identical.

• 한국수산과학회지
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• 제35권3호
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• pp.247-252
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• 2002

어육 단백질로부터 가식성 필름을 제조하기 위하여 명태와 고등어로부터 최적 단백질 추출조건을 구명하고, 필름 제조용 용액의 단백질 농도, pH 및 온도가 필름의 물성에 미치는 영향을 조사하였다. 명태의 일반성분 함량은 수분 $79.62\%$, 조단백질 $18.2\%$, 조지방 $0.6\%$, 회분 $1.3\%$였으며, 고등어는 수분 $69.1\%$, 조단백질 $20.1\%$, 조지방 $9.5\%$, 회분 $1.3\%$로서 명태가 고등어에 비하여 수분함량은 높고 조단백질과 조지방 함량은 낮았다. 또한, 황함유 아미노산인 cysteine과 methionine 함량은 명태 771mg/100 g, 고등어 746mg/ 100 g 으로서 이들 아미노산의 비율은 그다지 높지 않았다 명태와 고등어로부터 가용성 단백질의 추출률은 pH 12에서 가장 높았으며. 다음으로 pH 2, 11의 순이었고, 중성부근에서는 추출률이 낮았다. 한편 추출된 가용성 단백질을 등전점 분리시켰을 때, 단백질의 회수율은 명태는 pH 4.8 ($79.8\%$)에서, 고등어는 pH 5.0 ($64.1\%$)에서 가장 높았다. 어육 단백질 필름은 증류수 100mL에 단백질 4g (glycerol 1.6g) 을 첨가하여 pH 10.0로 조정한 다음 $90^{\circ}C$로 가열하여 제조하는 것이 물리적 특성면에서 가장 우수하였다.

• 한국식품과학회지
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• 제27권2호
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• pp.225-229
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• 1995

저칼로리 감미료로서 장내 미생물 균총을 개선한다고 알려진 대두 올리고당을 전처리 및 Steffen법을 이용하여 대두 침지액으로부터 분리, 회수하였다. 전처리로서 pH를 $3.5{\sim}4.0$으로 조절하거나, 염화칼슘을 당 대비 8%(w/w)를 첨가하여 대두 침지액 중에 함유된 단백질을 약 $25{\sim}30%$가량 제거할 수 있었다. 또한 대두 침지액에 염화칼슘과 산화칼슘 분말을 각각 당 대비 약 20%, $100{\sim}120%$씩 첨가한 후 $5^{\circ}C$에서 20분 동안 반응시키는 Steffen법을 이용하면 대두 침지액 중에 존재하는 대두 올리고당의 약 85%를 saccharate 형태로 분리, 회수할 수가 있었다. 이산화탄소로 당을 탈착시켜 회수한 결과 최종적으로 약 80%의 수율로 당을 회수할 수가 있었으며 단백질은 약 80% 정도 제거할 수가 있었다. 회수된 당액의 당조성은 대두 침지액과 유사하였다.

• Applied Biological Chemistry
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• 제32권4호
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• pp.424-434
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• 1989

식품공장 폐수에는 각종 유기물을 다량 함유하고 있다. 이와 같은 식품공장 폐기물의 미생물학적 처리효과를 검토하는 동시에 폐수 중에서 배양된 곰팡이 균체 단백질을 분리 회수함으로 해서 폐수처리비용을 절검하고, 단백질 함량이 높은 균체단백사료를 개발할 목적으로 식품공장 폐수의 BOD 및 COD를 낮은 수준으로 감소시키고 증식속도가 빠르며 균체수율이 높고 고농도의 단백질을 함유하며 소화율이 높은 균체를 생산할 수 있는 곰팡이로 Aspergillus fumigatus를 분리 선발하였고, 선발된 균주의 최적배양조건인 $35{\sim}40^{circ}C,\;pH\;4.0{\sim}4.5$에서 pilot plant의 연속배양장치를 이용하여 주정공장 폐수를 기질로 하여 일정시간 동안 배양하여 폐수의 BOD, COD를 90% 이상 감소시켜 폐수정화를 도모할 수 있었으며 균체단백질을 기준 배합사료에 첨가하여 실시한 동물사양 시험 결과, 사양동물의 체중증가량과 단백질 이용율이 대조표준 시험구에 준할 수 있는 효과를 보여 주었다.

• 한국식품과학회지
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• 제2권2호
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• pp.8-16
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• 1970

69종(種)의 각종 식물체(植物體)를 대상으로 하여 이것을 마쇄(磨碎)한 slurry로부터 총질소(總窒素)의 추출상황(抽？狀況)을 조사(調査)하고, 추출액(抽出液)으로 부터의 LPC의 제조방법(製造方法)을 검토(？討)하여 다음과 같은 결과(結果)를 얻었다. 1. 원료(原料)의 총질소(總窒素)의 함량(含量)이 클수록 총질소(總窒素)의 추출비(抽出比)는 커지며, 원료(原料)로부터의 추출(抽出)은 적어도 2회추출(回抽出)까지 필요(必要)하다. 원료엽체(原料葉體)로부터의 1차(次) 추출액(抽出液) $(E_1;\;%)$, 2次 抽出液$(E_2;\;%)$와 (T; %)사이에는 $E_1=0.8168T,\;E_2=0.1830T$의 1차(次) 관계식(關係式)이 성립(成立)한다. 2. pH 처리(處理)에 의한 LPC 생성(生成)에 있어서 pH 3 이하(以下)에서는 생성(生成)된 LPC의 색택(色擇)이 갈변(褐變)되고 제품(製品)의 탄력성(彈力性)이 커지며, 그 정도는 pH가 낮아질 수록 현저(顯著)해진다. pH 처리(處理)에 의한 LPC 생성(生成)의 지적(至適) pH 는 $3.5{\sim}4.5$ 라고 할 수 있다. 3 추출액(抽出液)으로 부터의 LPC의 생성(生成)은 TCA 처리(處理)> pH 4> pH 3> 열처리(熱處理)의 순서(順序)가 되며, TCA 처리(處理)에 비(比)하여 pH 4 처리(處理)는 10%감(減), pH 3 처리(處理)는 11.4%감(減), 열처리(熱處理)는 14.8%감(減)이었다. 4. pH 처리법(處理法)은 열처리법(熱處理法) 보다 LPC의 생성량(生成量)이 다소 높으나 대량처리시(大量處理時)의 pH 조절(調節)의 복잡성(複雜性)과 생성제품(生成製品)의 품질(品質)로 보아 열처리(熱處理)에 의한 LPC의 생성방법(生成方法)이 효과적(效果的)이고 간편(簡便)하다.

• 한국식품영양학회지
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• 제29권5호
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• pp.760-766
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• 2016

To increase the collagen recovery rate, bromelain (PB) and a microbial enzyme (PM) were used to treat to pork skin with single agent or combinations. The quality of collagen from the pork skin was evaluated by enzymatic treatments. The highest results for the solid contents and pork skin recovery rate obtained with the microbial-enzyme-bromelain mixtue (PMB) were 13.60% and 18.05% respectively. The result also showed that the color was affected by different types of enzyme treatments. Although PM treatment showed the highest result in the protein content of 251.30 mg/100 g, PMB treatment was the highest in the test of collagen content of 37.73 g/100 g among the treatments. However bands of the pork skin were detected widely at 130 kDa and 170 kDa ranges in SDS-PAGE. The band of PB treatment showed at the range of below 17 kDa, changed into a smaller molecular weight. The collagen content test of the pork skin by the treatments, collagen contents with combination treatment of pork skin with PMB (0.5%) resulted the highest in 43.76 g/100 g. Also the fat content at the above treatment was reduced to 11.12% compared to the other treatments. With these results of this experiment, we conclude that the enzymatic treatments were effective for the processing property of pork skin like enhancing the yield of collagen.

• Asian-Australasian Journal of Animal Sciences
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• 제30권4호
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• pp.514-522
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• 2017

Objective: The study aimed to assess the N use efficiency (NUE) of pig slurry (in comparison with chemical fertilizer) for each regrowth yield and annual herbage production and their nutritive value. Methods: Consecutive field experiments were separately performed using a single application with a full dose of N (200 kg N/ha) in 2014 and by four split applications in 2015 in different sites. The experiment consisted of three treatments: i) control plots that received no additional N, ii) chemical fertilizer-N as urea, and iii) pig-slurry-N with five replicates. Results: The effect of N fertilization on herbage yield, N recovery in herbage, residual inorganic N in soil, and crude protein were significantly positive. When comparing the NUE between the two N sources (urea and pig slurry), pig slurry was significantly less effective for the earlier two regrowth periods, as shown by lower regrowth dry matter (DM) yield, N amount recovered in herbage, and inorganic N availability in soil at the 1st and 2nd cut compared to those of urea-applied plots. However, the effect of split application of the two N sources was significantly positive at the last two regrowth periods (at the 3rd and 4th cut). The two N sources and/or split application had little or no influence on neutral detergent fiber (NDF) content, acid detergent fiber (ADF) content, and in vitro DM digestibility, whereas cutting date was a large source of variation for these variables, resulting in a significant increase in in vitro DM digestibility for the last two regrowth periods when an increase in NDF and ADF content occurred. Split application of N reduced the N loss via nitrate leaching by 36% on average for the two N sources compared to a single application. Conclusion: The pig slurry-N was utilized as efficiently as urea-N for annual herbage yield, with a significant increase in NUE especially for the latter regrowth periods.

• Journal of Microbiology and Biotechnology
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• 제19권4호
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• pp.416-423
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• 2009

Hepatitis B core antigen(HBcAg) is an important serological marker used in the diagnosis of hepatitis B virus(HBV) infections. In the current study, a fast and efficient preparative purification protocol for truncated HBcAg from Escherichia coli disruptate was developed. The recombinant HBcAg was first captured by anion exchange expanded bed adsorption chromatography integrated with a cell disruption process. This online capture process has shortened the process time and eliminated the "hold-up" period that may be detrimental to the quality of target protein. The eluted product from the expanded bed adsorption chromatography was subsequently purified using size-exclusion chromatography. The results showed that this novel purification protocol achieved a recovery yield of 45.1% with a product purity of 88.2%, which corresponds to a purification factor of 4.5. The recovered HBcAg is still biologically active as shown by ELISA test.