• Microbiology and Biotechnology Letters
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• v.1 no.2
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• pp.75-78
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• 1973

Effects of nitrogen sources, supplement of vitamins and minerals on the accumulation of 5'-inosinic acid by an adenineless mutant of Brevibacterium ammoniagenes were examined. Maximal yield of 5'-inosinic acid was attained by the use of yeast extract. as organic nitrogen source Casamino acid supplemented with $Mn^{＋＋}$, $Zn^{＋＋}$ Ca-D-pantothenate and thiamine HCl could be subsitute for it. Subsequent experiment using the defined medium showed that the concentration of these trace element in the medium affected inosinic acid accumulation markedly. And it was found that the simulataneous addition of $Mn^{＋＋}$ (20$\mu\textrm{g}$1). $Zn^{＋＋}$(10$\mu\textrm{g}$1). thiamine Hcl(10mg/1) and Ca-D-pantothenate (5mg/l) to the defined medium stimulated inosinic acid accumulation, from which 7mg/ml of inosinic acid was obtained.

• Journal of the Korean Society of Food Science and Nutrition
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• v.10 no.1
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• pp.67-76
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• 1981

By using the paper chromatograph technique affinity of amino acids to the mercury was compared with that of sodium thiosulfate, 2,3-dimercaptopropanol(BAL) and inosinic acid. Among the amino acids of testment three acids (Cysteine, Cystine and Methionine) which posses sulfide or disulfide radical exhibited a spot which combined more apparently with the mercury than other amino acids. However, in the mixed solutions of thiosulfate, BAL or inosinic acid with those amino acid and mercury, the mercury was moved into thiosulfate, BAL or inosinic acid spot. It was clear from the results that affinity of sodiume thiosulfate, BAL and inosinic acid to the mercury is higher than that of amino acids.

• Korean Journal of Food Science and Technology
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• v.1 no.1
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• pp.66-73
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• 1969

More thau thirty kinds of sea food pickles have been eaten in Korea. Out of these, salted small sardine pickle was analyzed of their components and investigated the enzyme characteristics concerned. Also studied was the effect of enzymes on the production of flavorous 5'-mononucleotides. The results are summarized as follows: 1) No accumulation of flavorous 5'-mononucleotides was demonstrated because RNA-depolymerase in the raw materials and the pickles tended to decompose RNA into nucleoside and phosphoric acid. 2) 5'-Inosinic acid and 5'-adenylic acid were found in large amounts in the salted small sardine pickle. 3) 5'-Inosinic acid was contained in the salted small sardine pickle in a significant concentration, and it might be considered to be inosinic acid-type.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.8
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• pp.1336-1344
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• 2018

Objective: This study aimed to observe whether high-pressure processing (HPP) affected aroma development and the degradation rate of umami taste-related ATP breakdown products, specifically inosinic acid in grass-fed beef during vacuum aging. Methods: Strip loin (longissimus lumborum) cuts obtained from six grass-fed Friesian Holstein steers (32 months old) on day 4 post slaughter were vacuum-packed and subjected to pressurization at 300 and 500 MPa for 180 s at $15^{\circ}C{\pm}2^{\circ}C$. The samples were then stored for 4 weeks at $5^{\circ}C{\pm}0.5^{\circ}C$ under vacuum and compared with the control (0.1 MPa). Results: HPP increased the shear force value, promoted moisture loss and lipid oxidation, induced surface paleness, stabilized pH during aging, and reduced bacterial load and growth. The shear force value of 500 MPa-treated samples remained higher than the control after aging, while no significant differences were found between the control and 300 MPa-treated samples. Degradation of inosinic acid and inosine occurred during pressurization, resulting in an increase in hypoxanthine content. However, the degradation rate in HPP-treated samples during aging was slower; therefore, inosinic acid and inosine content remained higher than in control samples. No significant differences were found in hypoxanthine content at the end of aging. HPP intensified the levels of hexanal, octanal, 2-methylbutanal, 3-methylbutanal, benzaldehyde, and 2,5-dimethylpyrazine in cooked-aged beef samples. Conclusion: HPP induced aroma development and delayed the degradation of inosinic acid. However, it also reduced the postmortem tenderization rate.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.2
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• pp.293-300
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• 2018

Objective: This study observed the effects of cooking method and final core temperature on cooking loss, lipid oxidation, aroma volatiles, nucleotide-related compounds and aroma volatiles of Hanwoo brisket (deep pectoralis). Methods: Deep pectoralis muscles (8.65% of crude fat) were obtained from three Hanwoo steer carcasses with $1^+$ quality grade. Samples were either oven-roasted at $180^{\circ}C$ (dry heat) or cooked in boiling water (moist heat) to final core temperature of $70^{\circ}C$ (medium) or $77^{\circ}C$ (well-done). Results: Boiling method reduced more fat but retained more moisture than did the oven roasting method (p<0.001), thus no significant differences were found on cooking loss. However, samples lost more weight as final core temperature increased (p<0.01). Further, total saturated fatty acid increased (p = 0.02) while total monounsaturated fatty acid decreased (p = 0.03) as final core temperature increased. Regardless the method used for cooking, malondialdehyde (p<0.01) and free iron contents (p<0.001) were observed higher in samples cooked to $77^{\circ}C$. Oven roasting retained more inosinic acid, inosine and hypoxanthine in samples than did the boiling method (p<0.001), of which the concentration decreased as final core temperature increased except for hypoxanthine. Samples cooked to $77^{\circ}C$ using oven roasting method released more intense aroma than did the others and the aroma pattern was discriminated based on the intensity. Most of aldehydes and pyrazines were more abundant in oven-roasted samples than in boiled samples. Among identified volatiles, hexanal had the highest area unit in both boiled and oven-roasted samples, of which the abundance increased as the final core temperature increased. Conclusion: The boiling method extracted inosinic acid and rendered fat from beef brisket, whereas oven roasting intensified aroma derived from aldehydes and pyrazines and prevented the extreme loss of inosinic acid.

• Applied Biological Chemistry
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• v.11
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• pp.1-27
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• 1969

More than thirty kinds of sea food pickles have been eaten in Korea. Out of these salted yellow tail pickle, salted clam pickle, salted oyster pickle, and salted cuttlefish pickle were employed for the analysis of their components, identification of main fermenting microbes, and determination of enzyme characteristics concerned. Also studied was the effect of enzymic action of microbes, which are concerned with the fermenting of pickles, on the production of flavorous 5'-mononucleotides and amino acids. The results are summarized as follows: 1. Microflora observed in the pickles are: (a) Total count of viable cells after 1-2 months of pickling was found to be $10^7$ and that after 6 months decreased to $10^4$. (b) Microbial occurence in the early stage of pickling was observed to be 10-20% Micrococcus spp., 10-20% Brevibacterium spp., 0-30% Sarcina spp., 20-30% Leuconostoc spp., ca 30% Bacillus spp., 0-10% Pseudomonas spp., 0-10% Flavobacterium spp., and 0-20% yeast. (c) Following the early stage of pickling, mainly halophilic bacteria such as Bacillus subtilis, Leuconostoc mesenteroides, Pediococcus halophilus and Sarcina litoralis, were found to exhibit an effect on the fermentation of pickle and their enzyme activities were in direct concern in fermentation of pickles. (d) Among the bacteria participating in the fermentation, Sarcina litoralis 8-14 and 8-16 strains were in need of high nutritional requirement and the former was grown only in the presence of purine, pyrimidine and cystine and the latter purine, pyrimidine and glutamic acid. 2. Enzyme characteristics studied in relation to the raw materials and the concerned microbes isolated are as follows: (a) A small amount of protease was found in the raw materials and 30-60% decrease in protease activity was demonstrated at 7% salt concentration. (b) Protease activity of halophilic bacteria, Bacillus subtilis 7-6, 11-1, 3-6 and 9-4 strains, in the complete media decreased by 10-30% at the 7% salt concentration and that of Sarcina litoralis 8-14 and 8-16 strains decreased by 10-20%. (c) Proteins in the raw materials were found to be hydrolyzed to yield free amino acids by protease in the fermenting microbes. (d) No accumulation of flavorous 5'-mononucleotides was demonstrated because RNA-depolymerase in the raw materials and the pickles tended to decompose RNA into nucleoside and phosphoric acid. (e) The enzyme produced in Bacillus subtilis 3-6 strain isolated from the salted clam pickles, was ascertained to be 5'-phosphodiesterase because of its ability to decompose RNA and thus accumulating 5'-mononucleotide. (f) It was demonstrated that the activity of phosphodiesterase in Bacillus subtilis 3-6 strain was enhanced by some components in the corn steep liquor and salted clam pickle. The enzyme activity was found to decrease by 10-30% and 40-60% at the salt concentration of 10% and 20%, respectively. 3. Quantitative data for free amino acids in the pickles are as follows: (a) Amounts of acidic amino acids such as glutamic and aspartic acids in salted clam pickle, were observed to be 2-10 times other pickles and it is considered that the abundance in these amino acids may contribute significantly to the specific flavor of this food. (b) Large amounts of basic amino acids such as arginine and histidine were found to occur in salted yellow tail pickle. (c) It is much interesting that in the salted cuttlefish pickle the contents of sulfur-containing amino acids were exceedingly high compared with those of others: cystine was found to be 17-130 times and methionine, 7-19 times. (d) In the salted oyster pickle a high content of some essential amino acids such as lysine, threonine, isoleucine and leucine, was demonstrated and a specific flavor of the pickle was ascribed to the sweet amino acids. Contents of alanine and glycine in the salted oyster pickle were 4 and 3-14 times as much as those of the others respectively. 4. Analytical data for 5'-mononucleotides in the pickles are as follows: (a) 5'-Adenylic acid and 3'-adenylic acid were found in large amounts in the salted yellow tail pickle and 5'-inosinic acid in lesser amount. (b) 5'-Adenylic acid, especially 3'-adenylic acid predominated in amount in the salted oyster pickle over that in the other pickles. (c) The salted cuttlefish pickle was found to contain only 5'-adenylic acid and 3'-adenylic acid. It has become evident from the above fact that clam and the invertebrate lack of adenylic deaminase and contain high content of adenylic acid. Thus, they were demonstrated to be the AMP-type. (d) 5'-Inosinic acid was contained in the salted yellow tail pickle in a significant concentration, and it might be considered to be IMP-type. 5. Comparative data for flavor with regard to the flavorous amino acids and the contents of 5'-mononucleotides are: (a) A specific flavor of salted yellow tail pickle was ascribed to the abundance in glutamic acid and aspartic acid, and to the existence of a small amount of flavorous 5'-inosinic acid. The combined effect of these components was belived to exhibit a synergistic action in producing a specific fiavor to the pickle. (b) A specific flavor of salted clam pickle has been demonstrated to be attributable to the richness in glutamic acid and aspartic acid rather than to that of 5'-mononucleotides.

• Journal of Animal Science and Technology
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• v.64 no.5
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• pp.950-969
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• 2022

This study aimed to determine the effect of dietary supplementation with Acremonium terricola culture (ATC) on the quality, conventional characteristics, and flavor substances of Hortobágy goose meat. A total of 720 one-day-old goslings were divided into four dietary treatments, each consisting of six cages of 30 goslings. The dietary conditions consisted of the control group and three treatment groups supplemented with 3, 5, or 7 g/kg ATC. In male geese, supplementation with 3 g/kg ATC elevated the crude ash (CA) content of the thigh muscle compared to the control group, and the CA content of the pectoralis major was significantly elevated when geese were supplemented with 5 g/kg ATC (p < 0.05). In females, compared with the control group, supplementation with 7 g/kg ATC enhanced the crude protein (CP) content of the pectoralis major. Supplementation with 7 g/kg ATC also increased the crude fat (CF) content of the pectoralis major in females as well as in both sexes; moreover, this supplementation dose increased the inosinic acid content of the thigh muscle in males and in both sexes. In contrast, supplementation with 5 g/kg ATC decreased the pH of the thigh muscle at 12 h postmortem (p < 0.01). No significant changes in meat color, water loss rate, shear force, moisture content or amino acid (AA) levels were observed after ATC supplementation (p > 0.05). Levels of saturated fatty acids (SFAs) and polyunsaturated FAs (PUFAs) in the pectoralis major and levels of SFAs, monounsaturated FAs (MUFAs), and PUFAs in the thigh muscle were not affected by the supplementation. Overall, ATC supplementation had positive effects on the pH, and CA, CP, CF, inosinic acid contents as well as on the FA composition of gosling meat. The optimal level of ATC supplementation was 7 g/kg in goslings from 1 to 70 days of age.

• Microbiology and Biotechnology Letters
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• v.25 no.5
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• pp.512-519
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• 1997

RNA accumulating strain of Torulopsis versatilis MT-1 was cultured in molasses medium for higher contents of RNA in cell. Yeast cells were harvested at logarithmic phase on synchronous culture. Yield of cells on dry base to input sugar was 59.5%. Crude protein content was 55.1% in cell. RNA content was 13.9%. Some problems found in the process for the preparation of yeast extracts were improved by the addition of culture broth of Streptomyces faecalis MSF which secrete RNase (5' nuclease and 5' adenylic acid deaminase). When the culture broth of S. faecalis MSF was added in autolysis process 46% of RNA in cell was converted to I and G(5' inosinic acid and 5' guanylic acid) in extract. By addition of 3-7% culture broth of S.faecalis MSF in autolysis or enzymolysis process at the start or early stage, RNA in extract was converted easily to I and G and protein in cells was easily extracted and hydrolyzed to amino acid. Taste of those yeast extracts was delicious. The yeasty smell in yeast extracts was removed. And cell debris was easily removed from extract.

• Journal of fish pathology
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• v.17 no.2
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• pp.75-82
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• 2004

Interferons are kinds of cytokines that play an important role in antiviral defense mechanisms during viral infection by converting cells to synthesize proteins that inhibit viral replication. In the present study, an antiviral response against Spring viremia of carp virus (SVCV) was developed in common carp, Cyprinus carpio following stimulation with the potent interferon inducer, poly inosinic : cytidylic acid (poly I:C). Poly I:C injected fish showed lower cumulative mortalities against SVCV than untreated fish did. Moreover, in vitro study showed that head kidney leucocytes (HKLs) produced an interferon-like cytokine (ILC) after stimulation with poly I:C. According cytopathic effect reduction (CPER) assay to examine antiviral activity of crude ILC, the capacity of HKLs for ILC production was highest at 1×$10^6$cells/ml and significantly enhanced when treated with 20~50$\mu{g}$/ml of poly I:C. The optimal temperature and concentration of FBS to induce the highest ILC production were $20^\circ{C}$ and 5%, respectively.

• Korean Journal of Microbiology
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• v.10 no.3
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• pp.109-116
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• 1972

Three strains among 120 adenineless mutants of Brevibacterium ammoniagenes described in the previous paper were screened out to accumulate UV absorbing substances in the culture broth. It was analyzed to be 5'-inosinic acid and hypoxanthine by means of two dimensional paper chromatography, UV absorption spectra and periodate oxidation. 5'-IMP was isolated from the culture broth of the mutant No. 203 with anion-exchange resin amberite IRA-400 and recrystallized from ethanol. It was proved identical to authentic sample by Infra-red absorption spectrum. The growth responses of the mutant No. 2013 were demonstrated to require adenine, but not with adenosine and 5'-AMP.