• 제목/요약/키워드: Heat inactivation

검색결과 127건 처리시간 0.018초

대두(大豆)의 날콩냄새 발생을 억제하는 간단한 방법 (A Simple Technique for Inhibiting Production of Green, Beany Flavor in Soybeans)

  • 해리이스나이더
    • 한국식품과학회지
    • /
    • 제5권1호
    • /
    • pp.33-35
    • /
    • 1973
  • 대두(大豆)를 침지(浸漬)후 $100^{\circ}C$에서 2분간 가열하면 불쾌한 풋 냄새의 발생을 충분히 억제할 수 있다. 건조한 대두(大豆)의 경우는 $100^{\circ}C$에서 3분간 가열하면 같은 효과를 나타낸다. 이와 같은 간단한 열처리(熱處理)는 병아리 사육시험의 결과 발육조해인자(發育阻害因子)를 불활성화(不活性化)시키기에는 불충분하다. 이취(異臭)의 조해(阻害)는 lipoxygenase 활성(活性)의 상실과 일치하며 이것이 그 원인인 것으로 생각된다.

  • PDF

인삼 단백질분획에 대한 폴리아크릴아미드 전기영동 (Polyacrylamide Gel Electrophoresis on Ginseng Proteins)

  • 김춘미;황정주
    • 약학회지
    • /
    • 제30권6호
    • /
    • pp.343-347
    • /
    • 1986
  • Korean ginseng was purified to obtain radioprotective protein fractions by buffer extraction, ammonium sulfate fractionation, CM-cellulose column chromatography, heat inactivation and Sephadex G-75 column chromatography. The final three fractions, GI, GII and GIII were subjected to Disc-polyacrylamide gel electrophoresis (PAGE) and SDS-PAGE. The molecular weights(M.W.) of native and denatured proteins were estimated by using regression line equations obtained from the mobilities of standard proteins. As the results, in Disc-PAGE, the GI fraction showed two protein bands with M.W. of above 213, 000 and 55, 000, GII showed one band with M.W. of 44, 000 and GIII, also one band with M.W. of 19, 000. In SDS-PAGE, GI fraction gave four subunit bands with M.W. of above 114, 000, 27, 000, 24, 000 and 19, 000, GII gave two bands with M.W. of 46, 000 and 22, 000, and GIII, one band of 19, 000.

  • PDF

새로운 non-apoptotic 세포사멸: ferroptosis (Novel non-apoptotic cell death: ferroptosis)

  • 우선민;권택규
    • Journal of Yeungnam Medical Science
    • /
    • 제34권2호
    • /
    • pp.174-181
    • /
    • 2017
  • Ferroptosis is a newly recognized type of cell death that results from iron-dependent lipid peroxidation and is different from other types of cell death, such as apoptosis, necrosis, and autophagic cell death. This type of cell death is characterized by mitochondrial shrinkage with an increased mitochondrial membrane density and outer mitochondrial membrane rupture. Ferroptosis can be induced by a loss of activity of system $X_c{^-}$ and the inhibition of glutathione peroxidase 4, followed by the accumulation of lipid reactive oxygen species (ROS). In addition, inactivation of the mevalonate and transsulfuration pathways is involved in the induction of ferroptosis. Moreover, nicotinamide adenine dinucleotide phosphate oxidase and p53 promote ferroptosis by increasing ROS production, while heat shock protein beta-1 and nuclear factor erythroid 2-related factor 2 inhibit ferroptosis by reducing iron uptake. This article outlines the molecular mechanisms and signaling pathways of ferroptosis regulation, and explains the roles of ferroptosis in human disease.

인삼단백질분획에 대한 SDS-폴리 아크릴아미드 전기영동 (SDS-polyacrylamide Gel Electrophoresis on Partially Purified Ginseng Proteins)

  • 김춘미
    • 약학회지
    • /
    • 제27권4호
    • /
    • pp.315-320
    • /
    • 1983
  • Ginseng proteins have been extracted and partially purified by the methods of ammonium sulfate fractionation, heat inactivation and Sephadex G-75 column chromatography. The final three fractions obtained (GI, GII and GIII) were subjected to paper chromatography and SDS-polyacrylamide gel electrophoresis. Molecular weights of polypeptide chains from each fraction were est-mated by the standard line obtained from the plot of electrophoretic mobilities against the logarithm of molecular weights of standard proteins. Results are as follows: 1) GI showed three protein spots and four polypeptides of which M.W. were 63,000, 60,000, 56,000, 51,000 and 34,200. 2) GII showed four protein spots and five polypeptides with their M.W. of 64,600, 56,000, 45,400, 35,800, end 25,200, 3) GIII showed three protein spots and four polypeptides with their M.W. of 66,000, 63,000, 56,000 and 22,000.

  • PDF

Clostridium botulinum and Its Control in Low-Acid Canned Foods

  • Reddy, N. Rukma;Skinner, Guy E.;Oh, Sang-Suk
    • Food Science and Biotechnology
    • /
    • 제15권4호
    • /
    • pp.499-505
    • /
    • 2006
  • Clostridium botulinum spores are widely distributed in nature. Type A and proteolytic type B bacteria produce heat-resistant spores that are primarily involved in most of the food-borne botulism outbreaks associated with low-acid canned foods. Food-borne botulism results from the consumption of food in which C. botulinum has grown and produced neurotoxin. Growth and toxin production of type A and proteolytic type B in canned foods can be prevented by the use of thermal sterilization alone or in combination with salt and nitrite. The hazardousness of C. botulinum in low-acid canned foods can also be reduced by preventing post-process contamination and introducing hazard analysis and critical control point (HACCP) practices during production. Effectiveness of non-thermal technologies such as high pressure processing with elevated process temperatures on inactivation of spores of C. botulinum will be discussed.

감자 Polyphenol Oxidase의 열안정성 (Thermostability of Polyphenol Oxidase from Potato (Solanum tuberosum L.))

  • 김나영;이민경;박인식;방극승;김석환
    • 한국식품영양과학회지
    • /
    • 제30권5호
    • /
    • pp.844-847
    • /
    • 2001
  • 감자로부터 polyphenol oxidase를 추출하여 열안정성에 영향을 주는 요인을 식품의 제조공정에 유용한 정보를 제공하기 위해 연구를 하였다. 감자의 PPO는 pH 7.0에서 가장 안정하였고, 이 효소는 8$0^{\circ}C$에서 1분간의 열처리로 효소 활성이 70% 저해되었다. 감자 PPO의 열안정성은 sodium chloride의 첨가로 감소되었으며, 2-mercaptoethanol과 dithiothreitol과 같은 환원제의 첨가로 역시 효소활성이 저해되었다.

  • PDF

Improvement of Virus Safety of a Human Intravenous Immunoglobulin by Low pH Incubation

  • Kim, In-Seop;Choi, Yong-Woon;Lee, Sung-Rae;Cho, Hang-Bok;Eo, Ho-Gueon;Han, Sang-Woo;Chang, Chong-Eun;Lee, Soung-Min
    • Journal of Microbiology and Biotechnology
    • /
    • 제11권4호
    • /
    • pp.619-627
    • /
    • 2001
  • n order to increase the virus safety of a human intravenous immunoglobulin (IVIg) that was manufactured by a successive process of cold ethanol fractionation, polyethylene glycol precipitation, and pasteurization ($60^{\circ}C$ heat treatment for 10h), a low pH incubation process (pH 3.9 at $25{\circ}C$ for 14 days) was employed as the final step. The efficacy and mechanism of the fraction III cold ethanol fractionation, pasteurization, and low pH treatment steps in the removal and/or inactivation of blood-borne viruses were closely examined. A variety of experimental model viruses for human pathogenic viruses, including the Bovine herpes virus (BHV), Bovine viral diarrhoea virus (BVDV), Murine encephalomyocarditis virus (EMCV), and Porcine parvovirus (PPV), were selected for this study. The mechanism of reduction for the enveloped viruses (BHV and BVDV) during fraction III fractionation was both inactivation and partitioning, however, it was partitioning in the case of the nonenveloped viruses (EMCV and PPV). The log reduction factors achieved during fraction III fractionation were ${\geqq}$6.7 for BHV, ${\geqq}4.7$ for BVDV, 4.5 for EMCV, and 4.4 for PPV. Pasteurization was found to be a robust and effective step in inactivating all the viruses tested. The log reduction factors achieved during the pasteurization process were ${\geqq}7.5$ for BHV, ${\geqq}4.8$ for BVDV, 3.0 for EMCV, and 3.3 for PPV. A low pH incubation was very effective in inactivating the enveloped viruses as well as EMCV. The log reduction factors achieved during low pH incubation were ${\geqq}7.4$ for BHV, ${\geqq}3.9$ for BVDV, 5.2 for EMCV, and 2.0 for PPV. These results indicate that the low pH treatment successfully improved the viral safety of the final products.

  • PDF

Functional Characterization of the ${\alpha}$- and ${\beta}$-Subunits of a Group II Chaperonin from Aeropyrum pernix K1

  • Lee, Jin-Woo;Kim, Se Won;Kim, Jeong-Hwan;Jeon, Sung-Jong;Kwon, Hyun-Ju;Kim, Byung-Woo;Nam, Soo-Wan
    • Journal of Microbiology and Biotechnology
    • /
    • 제23권6호
    • /
    • pp.818-825
    • /
    • 2013
  • We isolated and functionally characterized the ${\alpha}$- and ${\beta}$-subunits (ApCpnA and ApCpnB) of a chaperonin from Aeropyrum pernix K1. The constructed vectors pET3d-ApCpnA and pET21a-ApCpnB were transformed into E. coli Rosetta (DE3), BL21 (DE3), or CodonPlus (DE3) cells. The expression of ApCpnA (60.7 kDa) and ApCpnB (61.2 kDa) was confirmed by SDS-PAGE analysis. Recombinant ApCpnA and ApCpnB were purified by heat-shock treatment and anion-exchange chromatography. ApCpnA and ApCpnB were able to hydrolyze not only ATP, but also CTP, GTP, and UTP, albeit with different efficacies. Purified ApCpnA and ApCpnB showed the highest ATPase, CTPase, UTPase, and GTPase activities at $80^{\circ}C$. Furthermore, the addition of ApCpnA and ApCpnB effectively protected citrate synthase (CS) and alcohol dehydrogenase (ADH) from thermal aggregation and inactivation at $43^{\circ}C$ and $50^{\circ}C$, respectively. In particular, the addition of ATP or CTP to ApCpnA and ApCpnB resulted in the most effective prevention of thermal aggregation and inactivation of CS and ADH. The ATPase activity of the two chaperonin subunits was dependent on the salt concentration. Among the ions we examined, potassium ions were the most effective at enhancing the ATP hydrolysis activity of ApCpnA and ApCpnB.

바이러스 안전성이 보증된 돼지유래 골 이식재 제조 공정 개발 (Process development of a virally-safe dental xenograft material from porcine bones)

  • 김동명;강호창;차형준;배정은;김인섭
    • 미생물학회지
    • /
    • 제52권2호
    • /
    • pp.140-147
    • /
    • 2016
  • 동물유래성분을 원재료로 사용하는 의료기기는 원료물질 유래 바이러스가 오염될 가능성이 있기 때문에 생산과정 중 바이러스가 오염되지 않도록 하여야 한다. 또한 생산공정은 오염될 가능성이 있는 바이러스들을 불활화하거나 제거하는 공정을 포함하여야 한다. 본 연구를 통해 돼지유래 이종골을 원재료로 사용한 바이러스 안전성이 보증된 치과용 골이식재(THE Graft$^{(R)}$) 제조공정을 개발하였다. THE Graft$^{(R)}$ 제조공정은 30% 과산화수소수와 80% 에탄올을 각각 처리하여 지방을 제거하는 공정과 $1,300^{\circ}C$ 열처리 공정을 통해 콜라겐과 유기물을 제거하는 공정을 포함한다. 또한 최종적으로 생산된 hydroxyapatite 성분의 골이식재에 25 kGy의 감마선을 조사하여 감염성 위해인자를 불활화하는 공정을 포함한다. THE Graft$^{(R)}$의 형태학적 특성을 소유래 hydroxyapatite 성분의 골이식재인 Bio-Oss와 SEM과 TEM을 이용하여 비교한 결과 구조적 특성이 유사함을 확인하였다. $1,300^{\circ}C$ 열처리 공정과 25 kGy 감마선 조사 공정의 바이러스 불활화 효과를 평가하기 위해 transmissible gastroenteritis virus (TGEV), pseudorabies virus (PRV), porcine rotavirus (PRoV), porcine parvovirus (PPV)를 모델 바이러스로 선정하였다. $1,300^{\circ}C$ 열처리 공정에서 TGEV, PRV, PRoV, PPV 모두 검출한계 이하로 불활화되었으며, 바이러스 로그 감소 값은 각각 ${\geq}4.65$, ${\geq}5.81$, ${\geq}6.28$, ${\geq}5.21$이었다. 또한 감마선 조사 공정에서도 TGEV, PRV, PRoV, PPV 모두 검출한계 이하로 불활화되었으며, 바이러스 로그 감소 값은 각각 ${\geq}4.65$, ${\geq}5.87$, ${\geq}6.05$, ${\geq}4.89$이었다. 두 공정에서 TGEV, PRV, PRoV, PPV의 누적 바이러스 로그 감소 값은 각각 ${\geq}9.30$, ${\geq}11.68$, ${\geq}12.33$, ${\geq}10.10$이었다. 이상의 결과에 의하면, THE Graft$^{(R)}$ 제조공정은 바이러스 안전성 보증을 위한 충분한 바이러스 불활화 능력을 가지고 있는 것으로 판단된다.

Inhibition of Citrate Synthase Thermal Aggregation In Vitro by Recombinant Small Heat Shock Proteins

  • Gong, Weina;Yue, Ming;Xie, Bingyan;Wan, Fanghao;Guo, Jianying
    • Journal of Microbiology and Biotechnology
    • /
    • 제19권12호
    • /
    • pp.1628-1634
    • /
    • 2009
  • Small heat shock proteins (sHSPs) function as molecular chaperones that protect cells against environmental stresses. In the present study, the genes of hsp17.6 and hsp17.7, cytosolic class I sHSPs, were cloned from a tropical plant, Ageratina adenophorum. Their C-terminal domains were highly conserved with those of sHSPs from other plants, indicating the importance of the C-terminal domains for the structure and activity of sHSPs. The recombinant HSP17.6 and HSP17.7 were applied to determine their chaperone function. In vitro, HSP17.6 and HSP17.7 actively participated in the refolding of the model substrate citrate synthase (CS) and effectively prevented the thermal aggregation of CS at $45^{\circ}C$ and the irreversible inactivation of CS at $38^{\circ}C$ at stoichiometric levels. The prior presence of HSP17.7 was assumed to suppress the thermal aggregation of the model substrate CS. Therefore, this report confirms the chaperone activity of HSP17.6 and HSP17.7 and their potential as a protectant for active proteins.