• 생명과학회지
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• 제25권6호
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• pp.615-623
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• 2015

본 연구는 시멘트 노출에 따른 참갈겨니 조직의 형태 생리적 변화를 분석하여 용해된 시멘트 분말이 어류에 미치는 영향을 조사하고자 하였다. 용해된 시멘트 분말에 노출된 아가미는 노출기간이 길어질수록 이차새변의 간격이 불규칙해지고, 점액세포의 활성도 증가하고 있으며, 곤봉화, 부종, 상피세포의 박리가 이차새변에서 관찰되었다. 신장 조직에서는 보우만주머니 공간이 넓게 관찰되었고, 표피 조직은 표피층의 두께가 감소하고 진피층의 배열이 불규칙해지는 것으로 관찰되었다. 항산화효소와 LDH의 활성은 조직 및 노출기간에 따라 활성에 차이가 있는 것으로 나타났다. 표피조직에서 용해된 시멘트 분말에 의해 발현이 증가되는 단백질은 근단백질 생성과 관련된 스트레스 단백질로 확인되었고 발현이 저하된 단백질들은 해당과정과 에너지 대사에 관여하는 단백질로 조사되었다. 이러한 결과로 보아 시멘트 노출에 따른 스트레스는 참갈겨니 조직의 형태적 변형과 생리적 기능의 약화를 초래하여 어류의 생존에 커다란 위협이 될 요인으로 작용할 수 있을 것으로 사료된다.

• 한국수산과학회지
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• 제18권5호
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• pp.401-408
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• 1985

정어리육을 원료로 한 대중적 소비성향의 대량 소비를 할 수 있는 식품의 중간 소재를 개발할 목적으로 정어리의 연육가공방법과 연육의 성상과 이를 소재로 한 제품의 물성에 관여하는 원료의 선도, 세척방법, 첨가물, 저장조건 등 여러가지 가공조건의 최적화를 검토하였다. 그 결과는 다음과 같이 요약된다. 1. 정어리육의 단백질은 저온에 저장하여 선도를 유지하여도 급격히 불용화하여 제품의 탄력과 물성도 매우 저하하였다. 원료정어리의 저장온도가 $5^{\circ}C$인 경우는 3일이내에 $-20^{\circ}C$의 경우는 20일 이내에 연육의 탄력형성능이 한계에 도달하였다. 2. 연육의 세척에 의한 수용성단백질의 제거와 염용성단백질의 안정화 효과는 세척회수($3{\sim}6$회)에 따른 큰 차는 없이 $3{\sim}4$회의 세척으로 충분하였는데 세칙방법별로는 수세, 알카리세척 및 산용액 세척의 경우 수용성단백질의 제거가 각각 $32\%,\;80\%,\;75\%$로 알카리세척이 보다 효과적이였고 제품의 물성도 좋았으며 지방의 제거는 세가지 경우 모두 $50{\sim}60\%$였다. 3. 정어리연육 저장중의 단백질 안정화와 연육의 탄력형성능의 보존을 위하여 중합인산염과 sorbitol의 첨가효과를 검토하였는데 연육을 $-30^{\circ}C$ 저장하였을 경우 이들의 첨가비에 따라 즉 인산염과 sorbitol이 $0.3\%$와 $3\%$일 때 35일, $0.6\%$와 $3\%$일 때 28일, $0.6\%$와 $6\%$일 때 21일, sorbitol 단독 $3\%$와 인산염 단독 $0.3\%$일 때는 각각 14일, 무첨가의 대조시료는 7일 이내에 탄력형성 굴곡시험 A에 도달하였고, 연제품의 물성도 저하하셨다. 이때 연육의 탄력형성의 한계와 염용성단백질의 함량간에는 밀접한 관계가 있어 염용성단백질소 함량 8.0mg/g가 경계였다. 4. 세척과정에서 유실된 지방을 보충하여 지방함량 $5\%,\;7\%$ 되도록 하였을 때, 연제품의 탄력성과 물성에는 큰 변화가 없었다.

• 한국식품과학회지
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• 제6권2호
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• pp.79-85
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• 1974

근원섬유단백질의 생화학적 성질에 대하여서는 아직도 불명한 점이 많고, 특히 식품으로써의 근원섬유단백질의 저장 중의 변화에 대하여서는 규명되어야 할 점이 너무나 많다. 본 연구는 근원섬유단백질의 저장 중의 변화를 추구하기 위한 기초작업으로서 subcelular structure인 근원섬유를 재료로 하여 그 형태학적 측면과 생화학적 측면의 상관성을 비교 검토하였다. 근원섬유의 조제방법에 따라서 근원섬유의 근절(筋節)(sarcomere)의 길이는 변화하고 있었고 근절의 길이의 변화는 생화학적 성질. 즉 ATPase활성에 현저한 변화를 일으켰다. 근원섬유를 저농도의 trypsin으로 처리하면 근원섬유의 ATPase활성은 현저히 증가하나, 근원섬유의 위상차(位相差)현미경 상은 수축상태의 상을 나타내었다가 처리시간의 연장에 따라 sarcomere가 fragmentation을 나타냄을 보여주었다. 얻어진 결과로 근원섬유 중에는 ATPase활성을 저해하는 factor가 존재하며, 이 factor는 단백질의 inhibitory action은 아니고 steric effect임을 추정하였다. 또한 Z-line의 구성물질 중에 troponin의 관여가 추정되었다.

• Asian-Australasian Journal of Animal Sciences
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• 제16권9호
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• pp.1384-1389
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• 2003

In order to clarify one of the biological functions of pork, we investigated whether a peptic hydrolysate of denatured porcine crude myosin showed inhibitory activity against angiotensin I-converting enzyme (ACE), which contributed to hypertension. Our results indicated that this hydrolysate showed relatively strong activity, and we therefore attempted to separate the involved peptides, which were considered to be active substances. To isolate these active peptides, the hydrolysate was separated using a solidphase separation, gel filtration high-performance liquid chromatography (HPLC), and two kinds of reverse phase HPLC. In each stage of separation, many fractions were detected, almost all of which showed ACE inhibitory activity. Thus, we suggested that the activity of the hydrolysate as a whole was a result of the activities of the many individual peptides. Six peaks were distinguished, with yields from 34 to 596 ppm of original crude myosin. In addition to the six peaks, many other active fractions were found throughout the separation steps, strongly suggesting that whole porcine crude myosin itself had ACE inhibitory activity. Moreover, pork as food was considered to function as an ACE inhibitory material in vivo, because pork proteins consist primarily of crude myosin, which included almost all the myofibrillar structural proteins.

• Asian-Australasian Journal of Animal Sciences
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• 제18권1호
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• pp.133-140
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• 2005

Although amino acids are substrates for the synthesis of proteins and nitrogen-containing compounds, it has become more and more clear over the years that these nutrients are also extremely important as regulators of body protein turnover. The branched-chain amino acids (BCAAs) together or simply leucine alone stimulate protein synthesis and inhibit protein breakdown in skeletal muscle. However, it was only recently that the mechanism(s) involved in the regulation of protein turnover by BCAAs has begun to be defined. The acceleration of protein synthesis by these amino acids seems to occur at the level of peptide chain initiation. Oral administration of leucine to food-deprived rats enhances muscle protein synthesis, in part, through activation of the mRNA binding step of translation initiation. Despite our knowledge of the induction of protein synthesis by BCAAs, there are few studies on the suppression of protein degradation. The recent findings that oral administration of leucine rapidly reduced $N^{\tau}$-methylhistidine (3-methylhistidine; MeHis) release from isolated muscle, an index of myofibrillar protein degradation, indicate that leucine suppresses myofiblilar protein degradation. The details of the molecular mechanism by which leucine inhibits proteolysis is just beginning to be elucidated. The purpose of this report was to review the current understanding of how BCAAs act as regulators of protein turnover.

• Asian-Australasian Journal of Animal Sciences
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• 제19권5호
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• pp.739-743
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• 2006

Postmortem proteolysis of breast (BM) and leg (LM) muscles from Taiwan colored chickens (TCC) and silkie bantams (SB) at $5^{\circ}C$ were compared. Myofibrils were prepared from BM and LM samples that were randomly taken from the carcasses of SB and TCC after 0, 1, 3, 7 and 14 days of storage at $5^{\circ}C$. pH of samples was determined, and degradation of myofibrillar proteins was analyzed by the SDS-PAGE and western blots. The results showed that pH was lower in BM than in LM samples from both avian strains. Appearance of 30 kDa components and disappearance of titin and nebulin were more rapidly as seen on SDS-PAGE in BM than in LM samples. Western blots labeled with a monoclonal antibody to desmin also demonstrated that desmin degraded more quickly in BM samples. Our data might suggest that postmortem proteolysis occurred more rapidly in BM than in LM from both TCC and SB.

• Journal of Nutrition and Health
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• 제11권3호
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• pp.37-42
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• 1978

Actomyosin and myofibril were extracted from Korean native Goat muscle with the Weber-Edsall solution. ATPase activities and physiochemical properties were measured. The results obtained were as follows; 1) Mg-activitied ATPase activity of actomyosin and myofibrill from Korean native Goat muscle exhibited a common biphasic response, a typical ATPase pattern, that is high at a low ionic strength and low at a high ionic strength. Actomyosin showed high activity than myofibrill. 2) Mg-activited ATPase activity of actomyosin from muscle increased extraction time 24 hours. 3) EDTA-enhanced ATPase activity of actomyosin was greater than myofibrill and low at the low ionic strength, high at the high ionic strength. The difference of the activity were shown great broad pattern at the after 0.3M KCI concentration. 4) Effect of EGTA on-ATPase activity of myofibrill and actomyosin from muscle was measured, the Mg-ATPase activity was markedly depressed. 5) Solubility of actomyosin from muscle began to solubilize at KCI concentration of 0.28M and solubilized completely at the KCI concentration of 0.3M.

• 한국식품영양과학회지
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• 제27권3호
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• pp.482-488
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• 1998

This study was carried out to determine the effect of treating with salt-fermented shrimp on quality of pig meat. The treated pig meats were stored at 4$^{\circ}C$, 1$0^{\circ}C$, 2$0^{\circ}C$ or 4$^{\circ}C$ after placing 2$0^{\circ}C$ for 35 hours, respectively. Meat tenderness was improved more at 2$0^{\circ}C$ storage than at 1$0^{\circ}C$ and 4$^{\circ}C$ storage. However, in water holding capacity, the meat stored at 4$^{\circ}C$ was increased more than them of 1$0^{\circ}C$ and 2$0^{\circ}C$. Cooking loss was decreased more at 4$^{\circ}C$ than the other storage temperatures. When meat color observed, it was good at the early stage of storage but went down to the worse gradually. According to the result of SDS-PAGE, myofibrillar proteins were degraded more after treated with salt-fermented shrimp than the control. Among them, titin-I was especially degraded after 2 days at 4$^{\circ}C$ storage even though it was degraded after 1 day at 1$0^{\circ}C$ and 2$0^{\circ}C$ storage. These results suggest that salt-fermented shrimps cause to improve the quality of pork meats by increasing the meat color, meat tenderness and water holding capacity at the early stage of storage.

• Asian-Australasian Journal of Animal Sciences
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• 제17권5호
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• pp.700-704
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• 2004

Chinese-style pork jerky is a typical intermediate moisture meat product obtained by curing, drying and roasting pork samples. The chemical, physical and microbiological characteristics of pork jerky were evaluated throughout processing. The moisture content varied from 72.5% to 23.4 or 19.6% and aw varied form 0.97 to 0.74 or 0.72 in accordance with processing steps. The pork jerky roasted at $200^{\circ}C$ had higher shear value than roasted at $150^{\circ}C$ because the moisture content and aw of the former sample was lower than the later sample. The nitrite losses during whole processing steps amount to nearly 50%. The TBA value of pork jerky varied from 0.34 to 9.25 or 9.83 mg of malonaldehyde depended on processing steps. The VBN value of pork jerky ranging from 0.25 to 22.4 or 23.5 mg/kg depended upon processing steps. The ATPase activity of myofibrillar proteins during processing steps were partly or entirely denatured by the heat-drying or heat-roasting treatment. A gradual decrease in microorganism count during processing of pork jerky was also observed.

• 한국수산과학회지
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• 제29권6호
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• pp.754-760
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• 1996

Effects of washing and additives on the texture of squid surimi gel which has been known to hard to gelation due to high protease activities and many water solubles were studied by SDS-PAGE, compression test, jelly strength and transmission electron microscopy analysis (TEM). Myosin (205 kDa) heavy chain was the major protein in water soluble fractions. It was impossible to make a gel after washing of the minced squid meat. These results suggested that squid (Todarodes pacificus) minced meat does not need a washing for good jelly products. $3.0\%$ of bovine plasma protein (BPP) produced the hardest gel ($16\%$ harder than the control) among the additives including egg white (EW), potato extracts (PE) and transglutaminase-K (TG-K) by compression test (P>0.05). Microstructure of control, $2\%$ EW and $4\%$ TG-K treated gels showed a sponge-like structure with more vacant space. Gels containing $3\%$ BPP formed the most rigid and arranged networks. Those results indicates that poor gel-network formation Was due to the degradation of myofibrillar proteins by proteases contained in the minced meat, which result in non-interlinkage.