• Food Science of Animal Resources
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• v.40 no.6
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• pp.908-923
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• 2020

The objective of this study was to compare tastes-related components and eating quality properties between Hanwoo steer and cow meats. Longissimus thoracis (LT) muscles with same quality grade (1⁺ grade) collected from left sides of the steer and cow carcasses were used for analyses of technological quality traits, free amino acids (FAAs), metabolites, nucleotides, fatty acids and sensory attributes. there were no differences occurring in the chemical composition (fat, protein, moisture and collagen) and technological quality traits (cooking loss, water holding capacity, shear force and color) between the two beef types (p>0.05). The cow meat exhibited significantly higher amounts of some FAAs associated with umami (e.g., glutamic acid and lysine), sweetness (e.g., proline and glutamic acid) and saltiness (e.g., histidine and glutamic acid) compared to the steer meat (p<0.05). Regarding the nucleotides, no differences occurred in all the identified nucleotides between the two beef types (p>0.05). A total of 27 metabolites were identified, however, only some compounds (e.g., acetate, creatine, creatinine, glucose and inosine, etc.) showed their significantly higher amounts in the cow meat compared with those in the steer meat (p<0.05). In terms of sensory aspects, the panelists found no differences in scores of all the eating quality traits between the two sex types of beef (p>0.05). Overall, excepts some variations in tastes-active compounds, there were no differences in the quality characteristics in general and eating quality in particular between the cow and steer meats when they were in the same quality grade.

• Korean Journal of Food Science and Technology
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• v.4 no.4
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• pp.317-321
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• 1972

Octopus Octopus vulgaris was dried with open air at $17{\sim}20^{\circ}C$ for 90 hours. Nucleotides and related substances were collected by extraction with cold perchloric acid, and their amounts were determined by ion exchange column chromatography. The contents of inosine, hypoxanthine and ADP in raw sample were 9.4, 5.1 and 4.1 ${\mu}mole/g{\cdot}dry\;wt.$ respectively. ATP and AMP were very low in content. But IMP was not detected in Octopus muscle. ATP, ADP and inosine tended to degrade rapidly during sun drying while AMP and hypoxanthine were increased. Especially, hypoxanthine were increased about three times during sun drying and also it was increased about two times during three months storage after sun drying.

• The Korea Journal of Herbology
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• v.31 no.5
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• pp.15-23
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• 2016

Objectives : Araliae Continentalis Radix and Angelicae Pubescentis Radix have been used as the same medicinal name Korean and Chinese traditional medicines, respectively. The authentic Araliae Continentalis Radix is described only the root of Aralia continentalis in the Korean Pharmarcopoeia. However, the dried root of Angelica biserrata, Levisticum officinale, or Heracleum moellendorffii also has been distributed adulterants of Araliae Continentalis Radix. To develop a reliable method for identifying Araliae Continentalis Radix from adulterants, we carried out the analyses of universal DNA barcode sequences.Methods : Four plants species were collected from different habitate and nucleotide sequences of matK and rbcL were analyzed. The species-specific sequences and phylogenetic relationship were estimated using entire sequences of two DNA barcodes, respectively.Results : In comparative analysis of matK sequences, we were identified 104 positions of marker nucleotide for Ar. continentalis, 3 for An. biserrata, 4 for L. officinale and 8 for H. moellendorffii enough to distinguish individual species, respectively. Furthermore, we obtained marker nucleotides in rbcL at 42 positions for Ar. continentalis, 5 for An. biserrata and 2 for H. moellendorffii, but not for L. officinale. The phylogenetic tree of matK and rbcL were showed that all samples were clustered into four groups constituting homogeneous clades within the species.Conclusions : We confirmed that species-specific marker nucleotides of matK sequence provides distinct genetic information enough to identify four species. Therefore, we suggest that matK gene is useful DNA barcode for discriminating authentic Araliae Continentalis Radix from inauthentic adulterants.

• The Korean Journal of Physiology and Pharmacology
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• v.3 no.3
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• pp.275-282
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• 1999

Muscle strips and muscle cells from cat stomach were used to investigate whether spontaneously formed cyclic nucleotides were involved in the inhibition of gastric smooth muscle contraction. A phosphodiesterase inhibitor, 3-isobutyl-1-methylxanthine (IBMX), increased the levels of both cyclic GMP (cGMP) and cyclic AMP (cAMP) in resting state cells, while decreasing acetylcholine-induced muscle contraction. Under the influence of IBMX, SQ22536, an adenylyl cyclase inhibitor and methylene blue, a guanylyl cyclase inhibitor completely blocked increases in cAMP and cGMP respectively, without any effect on contraction. However, the combination of SQ22536 and methylene blue completely blocked increases in both cAMP and cGMP levels and stimulated contractions markedly even in the presence of IBMX. Muscle contraction inhibitors such as isoprenaline, vasoactive intestinal polypeptide and sodium nitroprusside also appeared to increase cyclic nucleotide levels which decreased contraction. Which nucleotide increased the most was dependent on the agonist used. Therefore, irrespective of the cyclic nucleotide class, the spontaneous formation of cyclic nucleotides should be considered in evaluating the mechanism of gastric smooth muscle relaxation.

• The Korean Journal of Physiology
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• v.29 no.1
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• pp.39-50
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• 1995

This study was designed to clarify the action of cyclic nucleotides, cyclic AMP and cyclic GMP, on phorbol 12,13-dibutyrate (PDBu)-induced contraction in rings isolated from rabbit carotid artery. Arterial rings, 2 mm in width, were myographied isometrically in an isolated organ bath. PDBu produced slowly developing, sustained contraction in rabbit carotid artery, in a dose dependent manner, which was independent of extracellular $Ca^{2+}$ PDBu-induced contraction was relaxed by staurosporine, which suggests that PDBu-induced contraction is mediated by protein kinase C (PKC). $^{45}Ca^{2+}$ uptake by rabbit carotid artery was increased by PDBu during depolarization, but not in control. Isoproterenol and sodium nitroprusside (SNP) relaxed phenylephrine-induced contraction. However, SNP but not isoproterenol relaxed the contraction induced by PDBu. Acetylcholine relaxed PDBu-induced contraction in the presence of the endothelium. 8-bromo-cyclic AMP, a permeable analogue of cyclic AMP, suppressed phenylephrine-induced contraction but not PDBu-induced contraction. 8-bromo cyclic GMP relaxed both of them with dose dependency. A large dose of forskolin relaxed PDBu-induced contraction. PDBu increased cyclic AMP without considerable change in the level of cyclic GMP. Based on these findings, PDBu-induced contraction of rabbit carotid artery was relaxed by cyclic GMP more effectively than cyclic AMP, and the action of cyclic AMP could be mediated by cyclic GMP dependent protein kinase. Therefore it is suggested that the antagonistic action between protein kinase C and cyclic GMP-dependent protein kinase plays a major role in the regulation of vascular tone.

• Journal of Ginseng Research
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• v.19 no.2
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• pp.127-133
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• 1995

The complete open reading frame (ORF) of o-subunit of the $F_1$ ATP synthase (atPA) in Korean ginseng mitochondria was identified by the sequence similarity with atPA genes in other plant mitochondria. The sequence alignment showed that the common translation initiation codon, ATG, in plant genes was replaced with GTG valid codon in Korean ginseng. The atPA gene from GTG to TGA termination codon was 1524 nucleotides long, and the sequence homology of nucleotides and deduced amino acids revealed high values of 92~97%. A deletion event of 6 nucleotides was observed at the 1468th nucleotide from the GTG in Korean ginseng, in contrast to that at the 1450th in other plants such as pea, common bean, soybean, sugar beet, and radish. An unidentified open reading frame (on7) was observed upstream of atmA ORF. No other ATG as an initiation codon was detected in the region between off and atmA ORF in Korean ginseng, although a pyrimidine cluster "TTTTCTTTT" was located in this region as in Oenothera and maize genes. It could be supposed that GTG codon in atpA gene of Korean ginseng mitochondria would act as an initiation codon as in microbial genes.ial genes.

• Food Science of Animal Resources
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• v.39 no.1
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• pp.93-101
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• 2019

Nucleotides play important roles in numerous intracellular biochemical processes and are used in infant formulas and other dairy products. However, domestic analytical methods for assessing nucleotide content in products have not yet been established, and therefore, methods for determining nucleotide content are urgently required. A rapid and simple analytical method for determining the content of five types of nucleotides in dairy products was improved using solid phase extraction clean-up and high-performance liquid chromatography with diode array detector. The extraction solvent used in the AOAC method was not well dissolved and was changed to hydrophilic EDTA-Na. In addition, the results obtained using the isocratic elution method and a single wavelength were similar to those obtained using the AOAC method, and the time taken for analysis was shortened from 40 min to 25 min. The process of method validation revealed the following parameters: accuracy (84.69%-102.72%), precision (1.51%-6.82%), linearity (0.999), and limit of detection (cytidine 5'-monophosphate, 0.09 mg/L; uridine 5'-monophosphate, 0.11 mg/L; adenosine 5'-monophosphate, 0.12 mg/L; guanosine 5'-monophosphate, 0.11 mg/L; and inosine 5'-monophosphate, 0.14 mg/L). The method was also used to determine the nucleotide concentration in 25 samples (infant formulas, 1.99-29.39 mg/100 g; and cow milk, 0.28-0.83 mg/100 g). The newly improved method was appropriate for analyzing nucleotides in infant formulas and other dairy products faster when compared to conventional methods.

• Journal of Yeungnam Medical Science
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• v.9 no.1
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• pp.90-101
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• 1992

In rat kidney, the changes in concentrations of nucleotides and their derivatives during ischemia induced by renal artery ligation was measured quantitatively with high performance liquid chromatography(HPLC). After the ligation of renal artery for 60minutes, the concentrations of the nucleotides and derivatives were measured. In ischemic tissue, IDP was significantly decreased from $217.4{\pm}12.68{\mu}g$ in control to $80.7{\pm}18.39{\mu}g$ (p<0.01) ; ATP, $307.2{\pm}56.63{\mu}g$ to $47.6{\pm}5.95{\mu}g$ (p<0.01) ; ADP+AMP, $227.1{\pm}7.98{\mu}g$ to $61.4{\pm}3.92{\mu}g$(P<0.01); $NAD^+$, $217.9{\pm}4.49{\mu}g$ to $126.6{\pm}10.44{\mu}g$(P<0.01) ; GTP, $202.5{\pm}23.76{\mu}g$ to $117.7{\pm}14.24{\mu}g$ (P<0.05) ; GMP, $54.5{\pm}9.03{\mu}g$ to $23.7{\pm}0.46{\mu}g$(p<0.05), and inosine, $16.6{\pm}3.45{\mu}g$ to $7.8{\pm}0.87{\mu}g$ (P<0.05). But hypoxanthine and xanthine were significantly increased from $113.0{\pm}15.58{\mu}g$ to $159.7{\pm}12.07{\mu}g$ (P<0.05) and from $87.7{\pm}6.77{\mu}g$ to $173.1{\pm}12.52{\mu}g$ (P<0.01). In ischemic kidney, concentration of ATP was decreased to 39.9% of control at 10 minutes, 19.8% at 30 minutes, and 15.5% at 60 minutes, and ADP+AMP were decreased to 70.3% of control at 10 minutes, 67.3% at 30 minutes, and to 27.0% at 60 minutes, but hypoxanthine and xanthine were increased to 121.5% and 127.1% at 10 minutes, 126.0% and 174.4% at 30 minutes, and 141.4% and 197.3% at 60 minutes Total adenosine nucleotides were decreased to 20.3% of control during 60 minutes of ischemia, but hypoxanthine and xathine were increased to 157.5 % of control. These results suggest that the changes in the concentration of nucleotides and their metabolic derivatives are useful indices of the extents of tissue ischemia in rat kidney.

• The Korean Journal of Pharmacology
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• v.17 no.2
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• pp.37-45
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• 1981

The importance of thyroid hormones for the survival of rats in the cold is along-established fact. Hypothyroid animals are unable to survive in a cold environment. It was also reported that acute exposure of rats, guinea pigs and rabbits to cold produced an increased secretion of TSH and thereby thyroid hormone secretion within 10 to 30 min, but this increase of thyroid activity disappeared quite rapidly during warming. However, in human study no significant difference was found in the concentration of $T_4$, TSH and cortisol between summer and winter. But plasma $T_3$ concentration was increased significantly in winter in 56 adult men. On the other hand, it has been also known that catecholamines are important in the maintenance of body temperature of rat exposured to cold. Abundant evidences suggest that the sympathetic nervous system is involved in the activation of nonshivering thermogenesis and that thyroid hormone metabolism and secretion are influenced by catecholamines and consequently by the activity of the sympatheticadrenal system. Many of the metabolic effects of catecholamines are associated with an increase in the level of cAMP mediated through activation of adenylate cyclase which converts ATP to cAMP. Other studies have shown that thyroid hormones affect the amount of adenylate cyclase present in the adipose tissue. On the other hand. it was also reported that a particulate cAMP phosphodiesterase activity in fat cells was modulated by the action of thyroid hormones. The objective of the present study was to determine the interaction between thyroid activity and cyclic nucleotides during acute exposure to cold. Albino rats weighing around 200 g were used as the experimental animal. The room temperature group was kept at $25^{\circ}C$ and the cold-exposured group was kept at $4^{\circ}C$ for 1 week or 2 weeks. Each group was subdivided into three subgroups; control, KI, and MTU group. At the end of experiment the animals were etherized and blood was taken from abdominal aorta for $T_4,\;T_3$ and cyclic nucleotides. The determinations of $T_3,\;T_4$ and cyclic nucleotides were carried out with a radioimmunoassay(RIA) method. The results were summerized as followings. 1) A significant increase of thyroid weight was observed in rats exposured to cold for 2 weeks. Furthermore, in rats administered MTU while to exposure to cold the thyroid weight was also increased significantly. 2) After 2 weeks $T_3$ concentration in the plasma of cold-exposured rats was significantly increased in KI group and MTU group as well as in control group. On the contrary, after 2 weeks of cold exposure $T_4$ level was decreased in control group. 3) In the case of cyclic nucleotides, plasma cAMP was increased in the control group after 1 or 2 weeks of cold exposure. However, cAMP level in plasma was rather significantly decreased in KI group and MTU group as well as in control group.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.26 no.2
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• pp.150-158
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• 1993

In order to investigate the content and seasonal variation of the extractive components including taste compounds, free amino acids, nucleotides and related compounds, quanternary ammonium bases, and guanidino compounds of ascidian collected from the south coast of Korea were determined bimonthy from April to October in 1990. The extractive nitrogen was composed of $60{\sim}62\%$ as free amino acids, $12{\sim}16\%$ as betaines, $5{\sim}9\%$ as nucleotides, and others as trimethylamine oxide(TMAO) and total creatinine. The muscle of ascidian was rich in such free amino acids as taurine, proline, glutamic acid, glycine and glycinebetaine. Most of nitrogenous compounds in the extractives showed a marked seasonal variation with a maximum in summer or autumn. AMP content was relatively high among nucleotides. Succinic acid, malic acid, lactic acid and pyroglutaric acid were the major organic acids in ascidian. The results of omission test suggested that the taste of ascidian is attributed to mainly free amino acid, betaines, nucleotides and nonvolatile organic acid in order.