• 한국축산식품학회지
• /
• 제39권6호
• /
• pp.888-902
• /
• 2019

Our aim was to investigate the effects of bromelain embedded in double emulsion (DE) on physicochemical properties of pork loin. We evaluated DE characteristics such as size, zeta potential, and microscopy after fabrication. We marinated meat with distilled water (DW), 1% (w/v) bromelain solution, blank DE, and 1% (w/v) bromelain loaded in double emulsion (DE E) for 0, 24, 48, and 72 h at 4℃, and prepared raw meat for control. The marinated samples were assessed for color, water holding capacity, cooking loss, moisture content, pH, protein solubility, Warner-Bratzler shear force (WBSF) and gel electrophoresis. The droplet size of 1% (w/v) bromelain embedded in DE was increased compared with blank DE (p<0.05) and values of zeta potential decreased. The increase in lightness and color difference range of the DE-treated group was lower than that of the DW-treated group (p<0.05). Moreover, treatment by immersion in 1% (w/v) DE E resulted in the highest water holding capacity values (p<0.05) and lower cooking loss values than water base treatment (p<0.05). Results for myofibrillar protein solubility and WBSF showed a similar trend. 1% (w/v) DE E showed degradation of myosin heavy chain after 48 h in sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Thus, bromelain-loaded DE is useful for controlling and handling enzyme activity in food industry.

• Journal of Microbiology and Biotechnology
• /
• 제24권11호
• /
• pp.1559-1565
• /
• 2014

Cellulase and xylanase are main hydrolysis enzymes for the degradation of cellulosic and hemicellulosic biomass, respectively. In this study, our aim was to develop and test the efficacy of a rapid, high-throughput method to screen hydrolytic-enzyme-producing microbes. To accomplish this, we modified the 3,5-dinitrosalicylic acid (DNS) method for microwell plate-based screening. Targeted microbial samples were initially cultured on agar plates with both cellulose and xylan as substrates. Then, isolated colonies were subcultured in broth media containing yeast extract and either cellulose or xylan. The supernatants of the culture broth were tested with our modified DNS screening method in a 96-microwell plate, with a $200{\mu}l$ total reaction volume. In addition, the stability and reliability of glucose and xylose standards, which were used to determine the enzymatic activity, were studied at $100^{\circ}C$ for different time intervals in a dry oven. It was concluded that the minimum incubation time required for stable color development of the standard solution is 20 min. With this technique, we successfully screened 21 and 31 cellulase- and xylanase-producing strains, respectively, in a single experimental trial. Among the identified strains, 19 showed both cellulose and xylan hydrolyzing activities. These microbes can be applied to bioethanol production from cellulosic and hemicellulosic biomass.

• Journal of Microbiology and Biotechnology
• /
• 제24권11호
• /
• pp.1495-1502
• /
• 2014

Metarhizium anisopliae is a widely studied model to understand the virulence factors that participate in pathogenicity. Proteases such as subtilisin-like enzymes (Pr1) and trypsin-like enzymes (Pr2) are considered important factors for insect cuticle degradation. In four M. anisopliae strains (798, 6342, 6345, and 6347), the presence of pr1 and pr2 genes, as well as the enzymatic activity of these genes, was correlated with their virulence against two different insect pests. The 11 pr1 genes (A, B, C, D, E, F, G, H, I, J, and K) and pr2 gene were found in all strains. The activity of individual Pr1 and Pr2 proteases exhibited variation in time (24, 48, 72, and 96 h) and in the presence or absence of chitin as the inductor. The highest Pr1 enzymatic activity was shown by strain 798 at 48 h with chitin. The highest Pr2 enzymatic activity was exhibited by the 6342 and 6347 strains, both grown with chitin at 24 and 48 h, respectively. Highest mortality on S. exigua was caused by strain 6342 at 48 h, and strains 6342, 6345, and 6347 caused the highest mortality 7 days later. Mortality on Prosapia reached 30% without variation. The presence of subtilisin and trypsin genes and the activity of these proteases in M. anisopliae strains cannot be associated with the virulence against the two insect pests. Probably, subtilisin and trypsin enzyme production is not a vital factor for pathogenicity, but its contribution is important to the pathogenicity process.

• Macromolecular Research
• /
• 제11권5호
• /
• pp.334-340
• /
• 2003

In order to fabricate new sustained delivery device of nerve growth factor (NGF), we developed NGF-loaded biodegradable poly(L-lactide-co-glycolide) (PLGA, the mole ratio of lactide to glycolide 75:25, molecular weight: 83,000 and 43,000 g/mole, respectively) film by novel and simple sandwich solvent casting method for the possibility of the application of neural tissue engineering. PLGA was copolymerized by direct condensation reaction and the molecular weight was controlled by reaction time. Released behavior of NGF from NGF-loaded films was characterized by enzyme linked immunosorbent assay (ELISA) and degradation characteristics were observed by scanning electron microscopy (SEM) and gel permeation chromatography (GPC). The bioactivity of released NGF was identified using a rat pheochromocytoma (PC-12) cell based bioassay. The release of NGF from the NGF-loaded PLGA films was prolonged over 35 days with zero-order rate of 0.5-0.8 ng NGF/day without initial burst and could be controlled by the variations of molecular weight and NGF loading amount. After 7 days NGF released in phosphate buffered saline and PC-12 cell cultured on the NGF-loaded PLGA film for 3 days. The released NGF stimulated neurite sprouting in cultured PC-12 cells, that is to say, the remained NGF in the NGF/PLGA film at 37 $^{\circ}C$ for 7 days was still bioactive. This study suggested that NGF-loaded PLGA sandwich film is released the desired period in delivery system and useful neuronal growth culture as nerve contact guidance tube for the application of neural tissue engineering.

• Animal cells and systems
• /
• 제16권4호
• /
• pp.280-288
• /
• 2012

Targeted degradation of proteins through ubiquitin-mediated proteolysis is an important control mechanism in various cellular processes. The process of ubiquitin conjugation is achieved by three enzyme complexes, among which the ubiquitin ligase complex (E3) is in charge of substrate specificity. The SCF (SKP1-CUL1-F-box) family portrays the largest and the most characterized member of the E3 ligases. For each SCF complex, the ubiquitination target is recognized by the F-box protein subunit, which interacts with the substrate through a unique C-terminal domain. We have characterized a novel F-box protein CFL-1 that represents a single LRR-type F-box (FBXL) in the Caenorhabditis elegans genome. CFL-1 is highly homologous to FBXL20 and FBXL2 of mammals, which are known to regulate synaptic vesicle release and cell cycle, respectively. A green fluorescence protein (GFP)-reporter gene fused to the cfl-1 promoter showed restricted expression around the amphid and the anus. Modulation of CFL-1 activity by RNAi affected the time interval between defecations. RNAi-treated worms also exhibited reduced tendency to form dauer when exposed to daumone. The potential involvement of CFL-1 in the control of defecation and pheromone response adds to the ever expanding list of cellular processes controlled by ubiquitin-mediated proteolysis in C. elegans. We suggest that CFL-1, as a single LRR-type F-box protein in C. elegans, may portray a prototype gene exerting diverse functions that are allocated among multiple FBXLs in higher organisms.

• 한국식품과학회지
• /
• 제10권1호
• /
• pp.27-35
• /
• 1978

돼지백혈구(白血球) lysosomal 효소를 여러 pH(7.0, 4.0), 온도(溫度) 및 처리시간(處理時間)($37^{\circ}C$에서 12, 25시간(時間). $4^{\circ}C$에서 36, 168시간(時間)으로 처리(處理)한 우(牛)의 요근섬유(腰筋纖維)의 기미세적변화(起微細的變化)를 TEM으로 관찰한 바 pH 7.0에서는 처리 온도(溫度)와 시간(時間)에 관계없이 Z-line, M-line, H-zone등의 분해(分解)를 나타내었으나, pH 4.0에서는 myofilament만이 현저(顯著)한 분해(分解)를 나타내었을 뿐, Z-line은 정상적(正常的)이어서 분해작용(分解作用)이 없음을 보였다.

• 한국식품과학회지
• /
• 제10권1호
• /
• pp.36-45
• /
• 1978

맥백혈구(脈白血球) Lysosomal 효소를 pH(7.0, 4.0), 온도($37^{\circ}C$, $4^{\circ}C$) 및 처리기간($37^{\circ}C$에서 12 24시간, $4^{\circ}C$에서 36 168시간)을 달리하여 처리(處理)한 우(牛)의 요근조직(腰筋組織)의 변화(變化)에 대(對)하여 endomysial connective tissue, sarcolemma 및 transverse ridge등 근(筋)섬유 표면조직(表面組織)의 변화(變化)를 SEM으로 관찰한 바, 처리온도(溫度)에 관계(關係)없이 pH 7.0에서는 endomysial connective tissue, sarcolenna 및 transverse ridge의 분해(分解)를 나타내어 이 효소의 높은 역가(力價)를 보였으나, pH4.0에서는 이들 표면조직(表面組織)에 변화(變化)가 없었으며 특(特)히 transverse ridge는 $37^{\circ}C$에서 24시간, 그리고 $4^{\circ}C$에서 7일간 처리(處理)하여도 변화(變化)를 나타내지 않아 안정(安定)됨을 보였다.

• KSBB Journal
• /
• 제21권1호
• /
• pp.54-58
• /
• 2006

본 연구의 목표는 새롭게 분리한 두 종의 균주 Microbacterium barkeri KCCM 10507과 Paenibacillus amylolyticus KCCM 10508 에서 분비되는 PVA 분해 효소의 특성을 알아보고자 하였다. 상기 두 종의 균주로부터 얻은 crude enzyme을 사용하여 PVA 분해 시험을 진행한 결과, SAO의 활성은 시험 시작 후2일 혹은 3일 후 최대를 보인 반면, BDH의 활성은 시험 내내 점차 증가하는 경향을 보였다 또한, 배지내에 PVA가 존재하면 이들 효소의 활성 이 유지되었으나, PVA가 배지에서 완전히 사라지게되면, PVA 분해 효소의 활성도 사라졌다. 배지에 다시 PVA를 주입하면 이들 효소의 활성이 다시 나타났다. 이 결과를 통해 상기 두 종의 효소는 PVA 분해와 밀접한 관계가 있음을 알 수 있었고, PVA는 SAO와 BDH의 활성에 의해 분해된다는 것을 알 수 있었다.

• KSBB Journal
• /
• 제26권5호
• /
• pp.393-399
• /
• 2011

Bacillus subtilis natto producing high level of a fibrinolytic enzyme was selected and Ultra Nattokinase$^{(R)}$ was manufactured by fermentation and purification. It was performed the evaluation of the antithrombotic effect of Ultra Nattokinase$^{(R)}$ (20,000 FU/g) with rat blood plasma. The maximum aggregation (inhibition ratio) was 71% (0%), 69% (2.8%), 62% (12.7%), 16% (77.5%) and 9% (87.3%), respectively, in the order of 0, 5, 10, 50 and 100 mg/mL of Ultra Nattokinase$^{(R)}$ solutions. Ultra Nattokinase$^{(R)}$ had antithrombotic effect, which was associated with the suppression of collagen-induced platelet aggregation. Ultra Nattokinase$^{(R)}$ in the topic of the FDP (fibrinogen degradation products) in blood coagulation tests showed a significant increasing trend. And based on the daily record of meal 39 people of ITT (what ?) group consisted with 19 people of NP (what ?) group and 20 people of PN (what ?) group except four people, two people who took vitamin K affecting the experiment and two people who took alcohol, finding to be taken Ultra Nattokinase$^{(R)}$ showed an increase in the FDP value after four weeks. In addition, FDP value of 41 people of ITT group except two people having metabolic syndrome was increased by Ultra Nattokinase$^{(R)}$.

• 한국식품과학회지
• /
• 제29권6호
• /
• pp.1191-1195
• /
• 1997

새우젓의 육류단백질 분해 특성을 파악하기 위하여 전기투석기를 이용하여 탈염하여 조효소액을 조제하였다. 새우젓의 염도는 전기투석 후 2% 이하로 낮아졌으며 투석 시간이 경과할수록 조효소액의 protease activity는 증가하였다. 새우젓 조효소액에 우육, 돈육, 계육 등의 육류 전근육단백질을 기질로 하여 $37^{\circ}C$에서 반응시켜 SDS-PAGE로 근원섬유 단백질의 분해양상을 측정하였다. 새우젓 조효소액은 매우 강력하게 육류단백질을 분해하였으며 가열 처리 및 비가열처리 기질 모두 원활히 분해하는 특성이 있었다. 이러한 육류 단백질 분해는 특히 가열 처리한 육류에서 더 크게 나타나 5분 이내에 거의 모든 근육 단백질 단백질의 분해가 일어났다. 가열변성된 기질을 사용하여 조효소액의 분해능을 측정하였을 때 계육의 분해가 가장 원활히 일어났으며 그 다음이 돈육, 우육의 순이었다.