• Asian-Australasian Journal of Animal Sciences
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• 제28권5호
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• pp.620-631
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• 2015

A total of 59 lactic acid bacteria (LAB) strains were isolated from corn stover silage. According to phenotypic and chemotaxonomic characteristics, 16S ribosomal DNA (rDNA) sequences and recA gene polymerase chain reaction amplification, these LAB isolates were identified as five species: Lactobacillus (L.) plantarum subsp. plantarum, Pediococcus pentosaceus, Enterococcus mundtii, Weissella cibaria and Leuconostoc pseudomesenteroides, respectively. Those strains were also screened for antimicrobial activity using a dual-culture agar plate assay. Based on excluding the effects of organic acids and hydrogen peroxide, two L. plantarum subsp. plantarum strains ZZU 203 and 204, which strongly inhibited Salmonella enterica ATCC $43971^T$, Micrococcus luteus ATCC $4698^T$ and Escherichia coli ATCC $11775^T$ were selected for further research on sensitivity of the antimicrobial substance to heat, pH and protease. Cell-free culture supernatants of the two strains exhibited strong heat stability (60 min at $100^{\circ}C$), but the antimicrobial activity was eliminated after treatment at $121^{\circ}C$ for 15 min. The antimicrobial substance remained active under acidic condition (pH 2.0 to 6.0), but became inactive under neutral and alkaline condition (pH 7.0 to 9.0). In addition, the antimicrobial activities of these two strains decreased remarkably after digestion by protease K. These results preliminarily suggest that the desirable antimicrobial activity of strains ZZU 203 and 204 is the result of the production of a bacteriocin-like substance, and these two strains with antimicrobial activity could be used as silage additives to inhibit proliferation of unwanted microorganism during ensiling and preserve nutrients of silage. The nature of the antimicrobial substances is being investigated in our laboratory.

• 한국식품영양학회지
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• 제10권4호
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• pp.528-532
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• 1997

새조개 여체부의 긴발을 제외한 나머지인 가공 부산물을 식량자원으로서 효율적 이용을 위한 한 방안으로 효소분해 후 가수분해물의 물성을 개선하여 다소의 조직감을 갖는 반고형 상태의 페이스트 젓갈의 제조와 품질개선에 관하여 검토하였다. 새조개 가공부산물에 절반량의 물과 4% Protease N. P.를 첨가하여 가수분해 후 여과하여 그 여액에 4% glucose를 첨가하여 10$0^{\circ}C$에서1시간 열처리하여 풍미개선, 효소의 불활성화 및 멸균을 시켰다. 물성개량제 즉 0.5% alginic acid, 1% pectin, 0.2% agar를 병용 첨가한 제품이 대조구에 비하여 조직감 및 물성개선의 효과를 나타내었고, 10,000 rpm에서 60분간 원심분리 후에도 조직감이 파괴되지 않아 그 때의 혼합안정성은 98.1%였다. 페이스트 젓갈의 성분은 수분 함량 57.7%, 총당 함량 20.6%, 총질소함향 1,458% 및 아미노질소량 1,187mg%이었으며, 총질소중 아미노질소가 차지하는 비율은 81.4%였다.

• Journal of Nutrition and Health
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• 제19권6호
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• pp.363-373
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• 1986

This study was devised to elucidate whether soused shrimp exhibits a digestive action on boiled pork meats. and the mechanism by which sousing with a high concentration of sodium chloride preserves nutrients in foods for a prolonged pe\ulcornerriod. Protease was isolated from soused shrimp using a combination of ammonium sulfate fractionation. DEAE - cellulose ion exchange chromatography and gel filtra\ulcornertion. The isolated protease had specific activity of 1.560 units. 210 purification fo\ulcornerld with an yield of 38%. Its optimum pH and temperature were 8.0 and $43^{\circ}C$ respectively. The molecular weight of the enzyme was 35.000. The Km value of the enzyme for casein was 1.6 x $10^{-6}$ M The e=yme required the presence of cu\ulcornerpric ion to exhibit its full activity. Eighty eight percent of the enzyme activity was in\ulcornerhibited by 3.5M NaCI showing a reversibly linear decrease of the enzyme activity as NaCI concentration increased. The nature of the inhibition by NaCl was rever\ulcornersible and noncompetitive. The protease activity in soused shrimp was well preser\ulcornerved with the elapse of time at least in part due to NaCI induced suppression of autodigestion. The enzyme was denatured by acid easily. i.e. 1% of the original activity remained after staying at pH 2 for 10 minutes. which is within the norm\ulcorneral range of pH of the human stomach. Soused shrimp was observed to be one of those containing the highest protease activity compared with the other soused foo\ulcornerds such as soused oyster. squid. clam. and Pollack intestine with respect to spec\ulcornerific activities of dialized 1:4 whole homogenates(w/v) in 5 mM sodium phospha\ulcornerte - 2.4 mM j3 - mercaptoethanol buffer. pH 8.0. Casein and boiled meats including pork, beef, and chicken appeared to be the good substrates for the protease. Casein was the best. Therefore. the ingestion of boiled meats including pork together with soused sh\ulcornerrimp would help digestion of boiled pork in human not only by increasing appe\ulcornertite also by the direct proteolytic digestion of boiled meats by soused shrimp to\ulcorner some extent. And a high concentration of sodium chloride inhibited the protease activity reversibly in a remarkable degree, which ensued in a significant retardat\ulcornerion of autodigestion of protein in foods by proteases, and hereby contributed to the preservation of foods for an extended period.

• Journal of Animal Science and Technology
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• 제59권10호
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• pp.23.1-23.11
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• 2017

Background: Although soybean meal (SBM) is excellent source of protein in diets for poultry, it is sometimes inaccessible, costly and fluctuates in supply. The SBM can partially be replaced by full-fat SBM, but the meals prepared from raw full-fat soybean contain antinutritional factors. To avoid the risk of antinutritional factors, heat treatment is always advisable, but either excessive or under heating the soybean could negatively affect the quality. However, the potential for further improvement of SBM by supplementing with microbial enzymes has been suggested by many researchers. The objective of this study was to evaluate the performance and ileal nutrient digestibility of birds fed on diets containing raw soybeans and supplemented with microbial protease. Methods: A $3{\times}2$ factorial, involving 3 levels of raw full-fat soybean (RFFS; 0, 45 or 75 g/kg of diet) and 2 levels of protease (0 or 15,000 PROT/kg) was used. The birds were raised in a climate-controlled room. A nitrogen-free diet was also offered to a reference group from day 19 to 24 to determine protein and amino acid flow at the terminal ileum and calculate the standardized ileal digestibility of nutrients. On days 10, 24 and 35, body weight and feed leftover were recorded to calculate the body weight gain (BWG), feed intake (FI) and feed conversion ratio (FCR). On day 24, samples of ileal digesta were collected at least from two birds per replicate. Results: When RFFS was increased from 0 to 75 g/kg of diet, the content of trypsin inhibitors was increased from 1747 to 10,193 trypsin inhibitors unit (TIU)/g of diets, and feed consumption of birds was also reduced (P < 0.05). Increasing RFFS level reduced the BWG from hatch 0 to 10 d (P < 0.01) and hatch to 24 d (P < 0.05). The BWG of birds from hatch to 35 was not significantly (P = 0.07) affected. Feed intake was also reduced (P < 0.05) during 0 to 35 d. However, protease supplementation improved (P < 0.05) the BWG and FCR during 0 to 24 d. Rising levels of RFFS increased the weight of pancreas (P < 0.001) and small intestine (P < 0.001) at day 24. Except for methionine, apparent and the corresponding standardized ileal digestibility of CP and AA were reduced (P < 0.01) by increasing levels of RFFS in diets. Conclusion: This study showed that some commercial SBM could be replaced by RFFS in broiler diets, without markedly compromising productivity. The AID and SID of CP and lysine were slightly improved by dietary supplementation of microbial protease.

• 농업과학연구
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• 제25권1호
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• pp.107-117
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• 1998

특수 가금육인 꿩고기의 이용성을 높이고 가공에 대한 기초자료를 얻기 위하여 꿩고기에 단백분해 효소를 작용시켜 추출물을 제조할 때 추출온도, 시간 및 사용한 효소의 첨가량에 따라 추출물의 조단백질 함량, 아미노태 질소 함량, 가수분해율 및 수율, 아미노산 조성 등을 분석하였다. 꿩고기 추출물 제조시 $130^{\circ}C$에서 추출한 조단백질의 함량은 $100^{\circ}C$에서 추출한 것보다 현저히 증가하였으나 아미노태 질소의 함량은 별 차이가 없었다. 꿩고기에 단백질분해 효소인 protease NP, prozyme A를 처리하면 조단백질의 함량 및 아미노태 질소 함량이 상당히 높아 졌으며 protease NP가 더욱더 실용적이었다. 꿩고기로부터 얻어지는 추출물의 수율은 $100^{\circ}C$에서 처리한 것은 2.24~7.10%, $130^{\circ}C$에서 5.51~10.45%이었으며, 추출 시간 및 효소 첨가량에 의한 영향은 비교적 적었다. 꿩고기의 추출 수율은 추출온도, 효소의 종류, 효소 첨가량, 추출시간의 순으로 영향을 미쳤다. 아미노태 질소 함량은 효소 처리한 것이 가장 높았으며, 효소 첨가량, 추출시간, 추출온도의 순으로 영향을 미쳤으나 처리간 함량의 변화는 적었다 꿩고기 추출물의 유리 아미노산 함량은 protease NP로 처리하는 것이 $100^{\circ}C$ 또는 $130^{\circ}C$에서 가열 처리하는 것보다 현저히 높았다.

• 한국자원식물학회지
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• 제27권1호
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• pp.22-28
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• 2014

꽃치자나무 추출물의 HIV-1 reverse transcriptase, protease 및 alpha-glucosidase에 대한 억제활성실험을 실시하였다. ELOSA 방법으로 실험한 역전사효소 억제활성 실험에서는 꽃치자나무 잎 MeOH 추출물 $100{\mu}g/ml$ 농도에서 13.4%의 약한 억제활성이 관찰되었고, 줄기의 메탄올추출물에서는 32.5%의 높은 HIV-1 protease 억제활성과 줄기의 메탄올 추출물에서는 26.1%의 alpha-glucosidase 억제활성이 관찰되었다. 그리고 HIV-1 복제 억제활성은 MT-4 세포에 대한 HIV-1 유도 세포변성억제를 광학현미경으로 관찰하여 살펴본 결과 잎과 줄기의 모든 추출물에서 HIV-1 바이러스 증식억제에 억제활성이 관찰되지 않았다. In silico 실험결과 주요성분인 crocetin이 81.8%의 높은 역전사 효소활성이 예측되었으며, genipin이 55.39%, geniposidic acid aglycone이 64.5% 역전사효소 활성이 예측되었다. 주로 aglycone의 활성이 높게 예측되었으며 배당체의 경우 활성이 현저하게 저하되는 것으로 나타났다.

• 미생물학회지
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• 제17권2호
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• pp.81-93
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• 1979

The mycelium of Rhizopus nigricans was harvested at intervals during the sporulation periods, fractioned into various cell components and analyzed the con!eiits of various cell materials in order to clarify the optimum conditions of sporulation and some characteristics of the metabolism during tke sporulation periods. The changes in enzyme activities, such as amylase and protease, were also measured during the sporulation period,. 1. Mycelium in distilled water culture, as control, did not sporulate but mycelial mat cultured in Petridish without mutrient spourulated. Optimum temperature range for sporulation was $20{\sim}25^{\circ}C$. 2. During the sporulation and maturation periods, proteins, especially alkali-labile protein were decreased remarkably but free amino acid and ninhydrin reactive substances in acid soluble fraction were increased, compared with control. 3. Acid solable polyphosphate was decreased but acid insoluble polyphosphate was increased, during the sporulation. 4. Carbohydrate and hexosamine in acid soluble fraction were increased, while carbohydrate in alkali insoluble residual fraction was decreased during the sporulation periods. 5. Amounts of UV-absorbing material in deoxyribonucleic acid fraction was increased a little but those in ribonucleic acid fraction was decreased, compared with control. 6. Intracellular amylases and proteases activities insporulating mycelial mat were increased continuously during the sporulation and maturation periods.

• Journal of Plant Biotechnology
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• 제33권1호
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• pp.27-32
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• 2006

파인애플 (Ananas comosus) 줄기에서 얻어지는 bromelain은 단백질 분해효소 중 cysteine protease의 복합체로 알려져 있다. 본 연구에서는 제주산 파인애플 줄기를 이용하여 bromelain 관련 유전자를 분리하였다. 분리된 BL1 유전자는 총 933개의 염기서열로 311개의 아미노산을 coding 하였다. 지금 까지 알려진 식물 유래 bromelain 관련 유전자와의 alignment 분석한 결과 BAA21929 유전자와 94%, T10516 유전자와 93% 및 P14518 유전자와 81%의 상동성을 보였다. BL1 유전자를 상추 게놈내에 도입하고자 NPTII 유전자 와 BL1 유전자로 제작한 pBI 121 BL 벡터를 Agrobacterium tumefacience LBA4404에 도입한 후, 상추잎 절편에 감염시켜 embryogenic callus 및 재분화 식물체를 육성하였다. 이들식물체로부터 T1세대를 육성하여 PCR 분석을 통해 왜래유전자의 도입 여부를 확인하였다. 또한 형질전환체의 발현여부는 Nothern blot분석 및 eno protease활성을 통해 형질전환체에서 BL1유전자가 안정적으로 상추세포내에서 발현되고 있음을 확인하였다. 따라서 본 실험에서 육성된 bromelain 관련 BL1 유전자가 도입한 형질전환 상추를 육종소재르 활용한다면 상업적으로 유용한 단백질을 분해하는 가수분해효소로써 건강 보조제, 사료첨가제 등에 널리 사용할 수 있을 것으로 생각되어진다.

• 한국식품영양과학회지
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• 제25권6호
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• pp.915-921
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• 1996

한국재래간장으로부터 분리한 Bacillus subtilis CCKS-111이 생성하는 protease 생산의 최적 배양조건은 2% soluble starch, 0.2% peptone, 0.1%(MH$_4$)$_2$S$_2$O$_{8}$ , 0.2% MgSO$_4$, pH 7.0, 35$^{\circ}C$ 에서 24시간 배양했을 때이다. 효소의 최적 작용 pH와 온도는 pH 9.0, 5$0^{\circ}C$였으며 , pH 6.0~11.0의 범위와 5$0^{\circ}C$이상에서 불안정하였다. 금속이온 중 Cu$^{2+}$에 의하여 활성이 증대되었으나 $K^{2+}$, Hg$^{2+}$등에 의하여 효소활성이 저해되었다. Ethylenediamineteraacetic acid 와 phenylmethane sulfonyl fluoride 처리에 의해 활성이 저해되어 금속이온의 영향을 받는 serine protease로 확인되었다. Km값은 2.313$\times$$10^{-4}$ M, V$_{max}$ 값은 39.216$\mu\textrm{g}$/min이었으며, hemoglobin보다 casein을 더 잘 가수분해하였다.

• 한국토양비료학회지
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• 제26권3호
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• pp.189-196
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• 1993

결명자(決明子) 종실(種實)에 기인(起因)하는 물질(物質)이 타(他) 식물(植物) 종자(種子)의 발아(發芽) 및 생육(生育)을 억제(抑制)하는 타감(他感) 현상(現象)을 보인다는 것이 확인(確認)되었으며, 이 현상(現象)을 이용(利用)하여 자연(自然) 생태계(生態系) 또는 농업(農業) 생태계(生態系)에서 널리 일어나는 타감(他感) 현상(現象)의 일반적(一般的)인 작용(作用) 기작(機作)을 이해(理解)하고자 결명자(決明子) 종실(種實)의 수용성(水溶性) 추출물(抽出物)을 처리(處理)하여 발아(發芽) 시간별(時間別)로 수분(水分) 함량(含量), ${\alpha}$-amylase의 활성(活性), protease의 활성, abscisin산(酸)의 함량(含量), 전(全) phenol 화합물(化合物)의 함량(含量) 등(等)을 측정(測定)하여 이를 무처리구(無處理區)와 비교(比較), 분석(分析)한 결과(結果)를 다음과 같이 요약(要約)한다. 1. 무우, 벼, 상치, 보리 종자(種子)의 발아(發芽) 실험(實驗)으로 결명자(決明子) 종실(種實)에 기인(起因)하는 물질(物質)이 발아율(發芽率)을 저하(低下)시키는 타감(他感) 현상(現象)을 보이며, 상치와 무우에서 특(特)히 뚜렷하였다. 2. 결명자(決明子) 종실(種實)의 수용성(水溶性) 추출물(抽出物)의 처리(處理)에 의한 무우의 발아저해(發芽沮害)는 단백질(蛋白質) 합성기(合成期)에 protease 활성(活性)(합성(合成))의 증가(增加) 이후에 수분함량(水分含量)의 감소(減少)와 더불어 전(全) phenol 화합물(化合物)의 축적(蓄積)(분해저해(分解沮害))의 순서(順序)로 진행(進行)되었다. 3. 반면, 벼에서는 결명자(決明子) 종실(種實)의 수용성(水溶性) 추출물(抽出物)의 처리(處理)에 의해서 abscisin산(酸)의 축적(蓄積)에 따른 ${\alpha}$-amylase의 활성(活性)(합성(合成))감소(減少)에 의해 발아(發芽)가 저해(沮害)되어 Einhelling의 가설(假說)과 부분적(部分的)으로 일치(一致)하였다.