• 미생물학회지
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• 제29권3호
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• pp.172-178
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• 1991

Intracellular purine nucleoside phosphorylase (PNP) from Saccharomyces cerevisiae was partially purified using ammonium sulfate fractionation, heat treatment, a DEAE-Sephadex A-50 anion exchange chromatography and a Sephadex G-100 gel filtration chromatography. The enzyme was purified 20 fold with 3% recovery. The stability of enzyme was kept by addition of inosine and dithiothreitol. The pH optimum was found to be from 6.3 to 7.3 PNP was sensitive to 10mM of $Hg^{2+}$ , $Cu^{2+}$ , and was inactivated completely by 2 mM of p-chloromercuribenzoate and 5,5'-dithiobis (2-nitrobenzoate). The enzyme was capable of catalyzing the phosphorolysis of inosine, deoxyinosine, guanosine, deoxyguanosine and adenosine.

• Journal of Microbiology
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• 제35권1호
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• pp.15-20
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• 1997

Kinetic studies were done to elucidate the reaction mechanism of purine nucleoside phosphorylase (PNP) in Micrococcus Luteus. PNP catalyzes the reversible phosphorolysis of ribonucleosides to their respective base. The effect of alternative competing substrates suggested that a single enzyme was involved in binding to the active site for all purine nucleosides, inosine, deoxyiosine, guanosine, deoxyguanosine, adenosine and deoxyadenosine. Affinity studies showed that pentose moiety reduced the binding capacity and methylation of ring N-1 of inosine and guanosine had little effect on binding to bacterial enzyme, whereas these compounds did not bind to the mammalian enzymes. The initial velocity and product inhibition studies demonstrated that the predominant mechanism of reaction was an ordered bi, bi reaction. The nucleoside bound to the enzyme first, followed by phosphate. Ribose 1-phosphate was the first product to leave, followed by base.

• 한국미생물·생명공학회지
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• 제9권1호
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• pp.45-50
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• 1981

Adenine-guanine 동시영양요구성인 Brevibacterium ammoniagenes D-21530을 사용하여 5'-IMP을 생산할 경우, 5'-IMP생성에는 탄소원으로 fructose가 glucose보다 효율적이었다. 반면에 균 생육에는 glucose를 탄소원으로 사용하는 것이 좋았다. Glucose와 fructose를 혼합하여 사용할 때 균 생육을 적절히 조절하여 5'-IMP축적을 증가시켜 줄 수 있었으며 fructose와 glucose의 혼합당에 있는 fructose의 함유율을 20∼40%범위로 하였을 때 5'-IMP생성이 최대가 되었고 fructose 단독으로 사용할 때보다 약 40% 증가되었다. 또한 영양요구성물질인 adenine과 guanine의 첨가농도가 증가함에 따라 균생육이 촉진되나 150㎎/l 이상에서는 정상상태였고, 5'-IMP생성은 50㎎/l 까지는 첨가 농도에 따라 급격히 증가하나 그 이상에서는 감소하였다.

• Asian-Australasian Journal of Animal Sciences
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• 제25권1호
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• pp.92-97
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• 2012

The trial was conducted to evaluate the effects of sea buckthorn leaves (SBL) on meat flavor in broilers during heat stress. A total 360 one-day-old Arbor Acre (AA) broilers (male) were randomly allotted to 4 treatments with 6 replicates pens pretreatment and 15 birds per pen. The control group was fed a basal diet, the experimental group I, II and III were fed the basal diet supplemented with 0.25%, 0.5%, 1% SBL, respectively. During the 4th week, broilers were exposed to heat stress conditions ($36{\pm}2^{\circ}C$), after which, muscle and liver samples were collected. High performance liquid chromatography (HPLC) was performed to measure the content of inosine monophosphate (IMP); Real-Time PCR was performed to determine the expression of the ADSL gene. The results showed that the content of breast muscle IMP of group I, II and III was significantly increased 68%, 102% and 103% (p<0.01) compared with the control, respectively; the content of thigh muscle IMP of group II and III was significantly increased 56% and 58% (p<0.01), respectively. Additionally, ADSL mRNA expression in group I, II and III was increased significantly 80%, 65% and 49% (p<0.01) compared with the control, respectively. The content of IMP and expression of ADSL mRNA were increased by basal diet supplemented with SBL, therefore, the decrease of meat flavor caused by heat stress was relieved.

• 한국식품영양과학회지
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• 제1권1호
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• pp.17-24
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• 1972

붕장어의 선어(鮮魚) 및 천일건조중(天日乾燥中)의 산가용성(酸可溶性) 핵산관련물질(核酸關聯物質)의 변화(變化)를 실험(實驗)하여 다음과 같은 결과를 얻었다. 1. 생붕장어에는 IMP함량(含量)이 월등하게 많았고, ATP, ADP, AMP 및 inosine, hypoxanthine은 양(量)이 적었다. 2. 천일건조중(天日乾燥中) ATP, ADP, AMP는 거의 완전(完全)히 소실(消失)되었고, 생원료중(生原料中)에 가장 많았던 IMP$(16{\mu}moles/g,\;dry\;base)$도 1/16로 감소(減少)하였다. 한편 inosine은 12배로 hypoxanthine은 약 3배로 증가(增加)하였다. 3. flavor quality 면으로 판단한다면 천일건조중(天日乾燥中)은 붕장어 가공법(加工法)으로서 효과적(效果的)인 방법(方法)이 못된다고 볼 수 있다.

• 한국축산식품학회지
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• 제34권4호
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• pp.448-456
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• 2014

Studies on the flavour characteristics of meat-based broth, quantification of flavour-related and functional compounds, and factors affecting the availability of such compounds are minimal. The present study was designed to determine the effects of sex on flavor-related and functional compounds in freeze-dried broth (FDB) made from Korean native chickens (KNC). Male and female KNC from a commercial strain (Woorimatdag$^{TM}$) were reared under similar commercial conditions. FDB was separately prepared using male and female birds aged 100 d (six birds of each sex) and analyzed for nucleotide, free amino acid, betaine, carnitine, carnosine, anserine, and creatine contents, and fatty acid composition. The levels of betaine, carnitine and creatine in FDB were not significantly different between the two sexes (p>0.05) in KNC. Carnosine and anserine were not detected in FDB samples. However, FDB from female chickens had significantly higher inosine-5-monophosphate and arachidonic acid contents than did FDB from male chickens. FDB prepared with male KNC contained higher levels of inosine, linoleic acid, glycine, alanine, lysine, and serine (p<0.05). However, glutamic acid, oleic acid, and DHA were present in comparable amounts (p>0.05) in FDB made from male and female KNC. Our findings suggest that the sex of KNC has significant effect on the contents of flavor-related compounds, but not functional compounds.

• 한국식품과학회지
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• 제28권5호
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• pp.882-887
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• 1996

홍합과 바지락의 건조 및 저장조건에 따른 핵산 및 그 관련물질과 유기염류의 함량변화를 조사한 결과는 다음과 같다. 홍합과 바지락 모두에서 ATP, ADP, AMP, inosine, adenosine 및 hypoxanthine의 6성분을 분석하였다. 홍합과 바지락 모두 생시료의 경우 adenosine의 함량이 높았으며, 건조 및 저장에 의해 ATP, ADP 및 AMP의 함량은 감소하고 inosone 및 hypoxanthine의 함량은 증가하였다. 그리고, TMAO, TMA및 총 creatinine의 함량은 두 시료 모두 함량이 아주 낮았으며, 건조 및 저장에 의해 TMAO 및 총 creatinine의 함량은 감소한 반면 TMA의 함량은 증가하였다.

• 한국수산과학회지
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• 제18권4호
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• pp.333-338
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• 1985

저렴한 동물성 단백질의 급원인 냉동대구의 식품학적 기초자료를 얻기 위해 북양산 냉동대구육을 천일건조 및 열풍 건조시켜 1개월간 저장하면서 유리아미노산 및 핵산관련물질의 변화를 실험하여 다음과 같은 결과를 얻었다. 생시료에는 proline, histidine, lysine및 alanine의 함량이 가장 많았고, 천일건조시료, 천일건조 저장시료, 열풍건조시료 및 열풍건조 저장시료에는 glycine, histidine, lysine, proline 및 alanine의 함량이 가장 많았으며, 총유리아미노산의 함량은 저장중 현저히 증가하였다. 핵산관련물질의 함량은 생시료와 건조시료 및 저장시료 모두 inosine의 함량이 가장 많았으며, 다음으로 IMP의 함량이 많았다. 이상의 결과들로 미루어 볼 때 glycine, histidine, lysine, proline 및 alanine등의 유리아미노산과 핵산관련물질로서는 IMP등이 냉동대구를 원료로 한 대구 건제품의 맛에 중요할 구실을 할 것으로 추정된다.

• Animal Bioscience
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• 제35권11호
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• pp.1771-1786
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• 2022

Objective: Inosine monophosphate (IMP) is a key factor that imparts of meat flavor. Differences in the IMP content in the muscles were evaluated to improve chicken meat quality. Methods: For this study, the IMP content was detected by high performance liquid chromatography. The gene expression profiles of Jingyuan chickens with different feeding patterns and different sexes were analyzed by RNA-sequencing (RNA-seq). Results: Breast muscle IMP content in free-range chickens was extremely significantly higher than that of caged chickens (p<0.01). Breast muscle IMP content in hens was also higher than that of cocks, but the difference was not significant. Correlation analysis showed that the breast muscle IMP content in caged hens and cocks was negatively correlated with the shear force, and the breast muscle IMP content in free-range hens was significantly negatively correlated with the shear force (p<0.05). The two key genes associated with IMP synthesis in chickens with different feeding patterns were glutamate-ammonia ligase (GLUL) and phosphodiesterase 10A (PDE10A). Bioinformatics analysis revealed that the GLUL and PDE10A genes are involved in glutamine biosynthesis and purine salvage pathways respectively. In addition, GLUL expression was positively correlated with the IMP content in caged and free-range chickens, and PDE10A expression was significantly positively correlated with the IMP content in caged and free-range chickens (p<0.05). Conclusion: These findings will facilitate the comprehension of the deposition of IMP in the muscles and thereby aid the process of selection and breeding of good quality local chickens.

• Journal of Animal Science and Technology
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• 제65권1호
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• pp.57-68
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• 2023

Flavor is an important sensory trait of chicken meat. The free amino acid (FAA) and nucleotide (NT) components of meat are major factors affecting meat flavor during the cooking process. As a genetic approach to improve meat flavor, we performed a genome-wide association study (GWAS) to identify the potential candidate genes related to the FAA and NT components of chicken breast meat. Measurements of FAA and NT components were recorded at the age of 10 weeks from 764 and 767 birds, respectively, using a White leghorn and Yeonsan ogye crossbred F2 chicken population. For genotyping, we used 60K Illumina single-nucleotide polymorphism (SNP) chips. We found a total of nine significant SNPs for five FAA traits (arginine, glycine, lysine, threonine content, and the essential FAAs and one NT trait (inosine content), and six significant genomic regions were identified, including three regions shared among the essential FAAs, arginine, and inosine content traits. A list of potential candidate genes in significant genomic regions was detected, including the KCNRG, KCNIP4, HOXA3, THSD7B, and MMUT genes. The essential FAAs had significant gene regions the same as arginine. The genes related to arginine content were involved in nitric oxide metabolism, while the inosine content was possibly affected by insulin activity. Moreover, the threonine content could be related to methylmalonyl-CoA mutase. The genes and SNPs identified in this study might be useful markers in chicken selection and breeding for chicken meat flavor.