• 분석과학
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• 제30권2호
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• pp.96-101
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• 2017

This study investigated the effect of centrifugation on tryptic digestion. This was done by applying different centrifugation speeds (6,000, 8,000, 10,000, 20,000, and $30,000{\times}g$) over various durations (0, 10, 20, 30, 40, 50, and 60 min) to digest two model proteins - cytochrome c and myoglobin. The intact proteins and resulting peptides were identified using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Centrifugation greatly improved the tryptic digestion efficiency of cytochrome c, where either an increase in centrifugation speed or in digestion duration significantly improved the digestion of cytochrome c. However, centrifugation did not noticeably improve the digestion of myoglobin; 16 h of centrifuge-assisted tryptic digestion at $30,000{\times}g$ barely removed the myoglobin protein peak. Similar results were also obtained when using conventional tryptic digestion with gentle mixing. When acetonitrile (ACN) was added to make 10% ACN buffer solutions, the myoglobin protein peak disappeared after 6 h of digestion using both centrifuge-assisted and conventional tryptic digestions.

• 한국식품영양학회지
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• 제11권2호
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• pp.221-227
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• 1998

본 연구는 냉장우육의 수분함량, 상대습도, pH, 색도 및 색소의 상관관계를 검토하였다. 등심과 사태의 표면 및 내부의 수분함량과 상대습도는 저장 중 일률적인 변화를 보이지 않았고, pH는 저장기간에 따라 높아지는 경향이었다. L값은 저장말기로 갈수록 높아졌고, b값은 표면이 내부보다 낮았다. 등심과 사태의 표면 및 내부에 공통적으로 myoglobin과 metmyoglobin이 음의 상관관계가 있고, 사태의 표면과 내부는 myoglobin과 L값이 양의 상관관계에 있으며, Myoglobin과 oxymyoglobin이 음의 상관관계가 있었다. 그러나 수분함량, 상대습도 및 pH는 색의 변화와 일률적인 상관관계는 없었다.

• Asian-Australasian Journal of Animal Sciences
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• 제23권9호
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• pp.1244-1249
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• 2010

Comparisons of properties between skeletal ryanodine receptor 1 (sRyR1)-heterozygous-mutated and normal types of meat were carried out in pigs using PSE (pale, soft and exudative) meat found during the butchering process. All samples considered to be PSE meat showed irregular running and disorder of the muscle fibers and a wider inter-fiber space upon light microscopic observation. Electron microscopy revealed disintegration, twisting, and disorder of the myofibril arrangement and elimination of the Z line in PSE meat, compared with normal meat. Meat property tests demonstrated greater decreases in water holding capacity, moisture and sarcoplasmic protein, and higher $L^*$ values for the meat color index in PSE meat than in normal meat, but there were no differences in these factors between genetically normal and sRyR1-heterozygous PSE meat. On the other hand, higher $a^*$ and $b^*$ values were observed in sRyR1-heterozygous than in normal PSE meat, and similar alterations to the a* value were observed in terms of the amount of myoglobin and density of the 17-kDa protein band, corresponding to the molecular mass of myoglobin, on SDS-PAGE gels. These results suggest that sRyR1-heterozygous PSE pork contains much more myoglobin than genetically normal PSE meat.

• 한국축산식품학회지
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• 제30권4호
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• pp.626-633
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• 2010

This study examined the relationship between meat color and myoglobin content, and evaluated their influence on muscle fiber characteristics and overall pork quality. Four groups of pigs were classified by lightness (CIE $L^*$) and redness (CIE $a^*$): HH, high lightness and high redness; HL, high lightness and low redness; LH, low lightness and high redness; LL, low lightness and low redness. Myoglobin content ranged from 1.2 mg/g to 2.1 mg/g, and was highest in the LH group and lowest in the LL group (p<0.05). Myoglobin content correlated significantly with redness (CIE $a^*$) (r = 0.45, p<0.01). Fiber compositions of type I and IIA were closely related to lightness and redness. Pork with higher sizes of type IIA and IIB fibers had lower lightness and redness, respectively, which was tougher than the other pork. Pork having the highest lightness and lowest redness, often considered "pale", has higher values in drip loss than the other classes of pork tested.

• 한국수산과학회지
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• 제35권2호
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• pp.162-165
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• 2002

백색육어를 배소한 경우와 배소한 시료를 저온에 저장 후, 단계적으로 가열처리했을 때 일어나는 산화에 의한 heme 화합물의 변화를 조사하였다. Heme 화합물 중 myoglobin 함량은 각시가자미나 조기 모두 180$^{\circ}C$에서 20분간 어피 제거육의 상태로 배소한 것이 상대적으로 감소폭이 컸으며 가열, 재가열에 의해서도 감소하는 경향이었다. Myoglobin의 감소 추세에 따라 metmyoglobin 함량은 역으로 점차 증가하는 경향이었으며, 배소온도가 낮을수록 또한 어피를 제거함으로써 생성된 metmyoglobin의 함량이 높았다. 총철 함량은 배소온도와 시간을 달리하여 처리하여도 두 어종 모두 생시료와는 함량 차이가 거의 없었다. 비 heme 철은 각시가자미의 경우 생시료에는 총철함량에 대해 약 $20\%$ 정도 함유되어 있었으나, 180$^{\circ}C$에서 20분간 어피 제거육의 상태로 배소했을 경우 생시료에 비해 약 2배 정도 증가하였다. 조기는 생시료에는 건물당으로 약 0.8mg/100g 함유되어 있었으나 배소, 가열 및 재가열과 같은 반복되는 가열과정에 의해 증가하였다. Heme 철 함량은 각시가자미와 조기 모두 비 heme 철의 증가에 반비례해서 감소하였으며 또한 배소시간이 길수록 그리고 어피 잔존육보다는 어피 제거육의 감소폭이 더 컸다.

• Preventive Nutrition and Food Science
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• 제9권2호
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• pp.183-186
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• 2004

Various myoglobin derivatives were manufactured in pork and beef ribeye in the laboratory and their colorimetric values were measured with a chromameter. The average values of L＊ and a＊ of pork pigments were higher and b＊ values were lower than those of beef pigments. Oxymyoglobin (bright red) is considered to be a desirable fresh red meat pigment for consumer acceptance. The means of L＊, a＊ and b＊ values of oxymyoglobin were 36.41, 27.32 and 4.71 for pork and 30.54, 25.58 and 9.81 for beef, respectively. Nitrosyl hemochrome, the pigment of processed meat products like sausages and hams had L＊, a＊ and b＊ values of 47.93, 26.85 and 6.63 for pork and 41.82, 23.19 and 11.82 for beef. It was found that as a discoloration developed in meat and the meat color turned to brown, the L＊, b＊ values increased and the a＊ value decreased.

• Bulletin of the Korean Chemical Society
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• 제26권1호
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• pp.151-156
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• 2005

The conformational dynamics of heme pocket, a small vacant site near the binding site of heme proteins -myoglobin (Mb) and hemoglobin (Hb), was investigated after photolysis of carbon monoxide from MbCO and HbCO in D$_2$O solution at 283 K by probing time-resolved vibrational spectra of photolyzed CO. Two absorption bands, arising from CO in the heme pocket, evolve nonexponentially in time. The band at higher energy side blue shifts and broadens with time and the one at lower energy side narrows significantly with a negligible shift. These spectral evolutions are induced by protein conformational changes following photolysis that modify structure and electric field of heme pocket, and ligand dynamics in it. The conformational changes affecting the spectrum of photolyzed CO in heme pocket likely modulates ligand-binding activity.

• Bulletin of the Korean Chemical Society
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• 제24권10호
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• pp.1470-1474
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• 2003

The dynamics of the tertiary conformation of myoglobin (Mb) after photolysis of carbon monoxide was investigated at 283 K solution by probing amide I and II bands using femtosecond IR absorption spectroscopy. Time-resolved spectra in the amide region evolve with 6-12 ps time scale without noticeable subpicosecond dynamics. The spectra measured at 100 ps delay after photolysis is similar to the difference FTIR spectrum at equilibrium. Time-resolved spectra of photoexcited Mb evolve modestly and their amplitudes are less than 8% of those of photolyzed MbCO, indicating that thermal contribution to the spectral evolution in the amide region is negligible. These observations suggest that the conformational relaxation ensuing photolysis of MbCO be complex and the final deoxy protein conformation have been substantially formed by 100 ps, probably with 6- 12 ps time constant.

• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2001년도 추계 수산관련학회 공동학술대회발표요지집
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• pp.129-130
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• 2001

식육 제품 및 육가공품의 색은 그 식품의 품질과 선호도를 결정하는 중요한 척도로서 사용되며, 소비자는 밝은 척색의 육이나, 갈-회색의 가열한육 및 핑크색의 숙성된 육을 더욱선호한다(C. JO., et al. 2000). Hemo계 색소는 동물성 식품색소로, 적색은 주로 육 색소인 myoglbin과 혈색소인 hemoglobin에 의한 것이다. 육색소인 myoglobin은 공기 중에 방치하면 산소와 결합하여 Oxymyoglobin으로 변화하여 선명한 선홍색을 띄게 된다. 육류를 가열하면 일부 산화되지 않고 있던 myoglobin이 Oxymyoglobi을 거쳐 metmyoglobin으로 된다. (중략)

• The Korean Journal of Physiology and Pharmacology
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• 제18권5호
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• pp.419-423
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• 2014

The purpose of the present study was to investigate cardiac damage biomarkers after a triathlon race in elite and non-elite athlete groups. Fifteen healthy men participated in the study. Based on performance, they were divided into elite athlete group (EG: n＝7) and non-elite athlete group (NEG: n＝8). Participants' blood samples were obtained during four periods: before, immediately, 2 hours and 7 days after finishing the race. creatine kinase (CK), creatine kinase-myoglobin (CK-MB), myoglobin, and lactate dehydrogenase (LDH) were significantly increased in both groups immediately after, and 2 hours after finishing the race (p<.05). CK, CK-MB, and myoglobin were completely recovered after 7 days (p<.05). Hematocrit (Hct) was significantly decreased in both groups (p<.05) 7 days after the race. LDH was significantly decreased in the EG (p<.05) only 7 days after the race. Homoglobin (Hb) was significantly decreased in the NEG (p<.05) only 2 hours after the race. Although cardiac troponin T (cTnT) was significantly increased in the EG but not in the NEG 2hours after the race (p<.05), there was no group-by-time interaction. cTnT was completely recovered in both groups 7 days after the race. In conclusion, cardiac damage occurs during a triathlon race and, is greater in elite than in non-elite. However, all cardiac damage markers return to normal range within 1 week.