• Microbiology and Biotechnology Letters
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• v.21 no.3
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• pp.276-280
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• 1993

Cell lytic enzyme, 5'-phosphodiesterase, and AMP-deaminase were used to produce yeast extract as a natural seasoning from beer yeast cells. Prior to the addition of cell lytic enzyme, heat treatment was performed to increase the cell wall degradation` the optimum condition of the cell lytic enzyme was 50C at pH 7.0. The production yields by the enzymatic method and conventional autolysis method were 42% and 35%, respectively. The total quantity of 5'-nucleotides, GMP and IMP, produced by enzymatic method was increased by 45% than that by the conventional method. Futhermore, the operation time of enzymatic method was only 6.5 hrs, significantly reduced from 24 hrs of the conventional method.

• 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.

• Korean Journal of Food Science and Technology
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• v.28 no.1
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• pp.152-156
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• 1996

Taste components of traditional kochujang from 55 households were investigated. The major free sugars in traditional kochujang (fermented hot pepper-soybean paste) were glucose $(8.21{\pm}5.62%)$ and maltose $(6.95{\pm}7.27%)$ and the minors were fructose $(1.88{\pm}1.27%)$ and sucrose $(1.05{\pm}1.21%)$. Succinic $(901.83{\pm}826.23\;mg%)$, citric $(484.16{\pm}242.89\;mg%)$ and lactic $(381.63{\pm}367.88\;mg%)$ acids in traditional kochujang were found in large amounts and acetic, oxalic, and formic acids in smaller amounts. The traditional kochujang contained large amounts of proline $(10.66{\pm}6.27\;mg%)$, glutamic acid $(9.27{\pm}10.97\;mg%)$, aspartic acid $(9.14{\pm}5.84\;mg%)$, lysine $(6.19{\pm}6.66\;mg%)$, and serine $(5.72{\pm}3.79\;mg%)$, and the total free amino acid content was 64.35mg%. Among the nucleotides and their related compounds in traditional kochujang, CMP $(42.90{\pm}28.16\;mg%)$ were the most abundant major compounds and hypoxanthine $(6.86{\pm}3.45\;mg%)$, IMP $(5.59{\pm}5.84\;mg%)$, inosine $(4.58{\pm}6.91\;mg%)$ and GMP$(3.36{\pm}3.93\;mg%)$ were found in smaller amounts, and AMP and UMP were also found in minor.

• Korean Journal of Poultry Science
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• v.38 no.2
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• pp.137-144
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• 2011

The current work was carried out to investigate the effect of crossbred Korean native chickens (KNC) on fatty acid, amino acid and nucleotide-related compounds contents of chicken meat. A total of 360 male chicks (1d of age) was used in this work and were divided 4 groups as A) (KNC egg-meat type C strains ${\times}$ KNC meat type S strains) ${\times}$ Ross broiler, B) (KNC egg-meat type C strains ${\times}$ KNC meat type H strains) ${\times}$ KNC meat type S strains, C) (KNC native R strains ${\times}$ KNC meat type S strains) ${\times}$ KNC meat type H strains and D(White Semibroiler Chickens) strains for 5 weeks at the flat house. Palmitic acid and vaccenic acid were highest in C strain meat, and myristic acid and linolenic acid were lowest in A strain meat (p<0.05). Saturated fatty acid was lowest in C strain meats (p<0.05). Valine, leucine, phenylalanine and lysine of essential acid were low in A strain meat. Cystine, aspartic acid, glycine, alanine and proline were also low in A strain meat. Hypoxanthin (Hx) was high compared other strains at 5 weeks and low at 10 weeks. IMP was high compared other strains at 5 and 10 weeks. AMP has not significant difference among strains at 5 weeks but B strain was high other strains at 10 weeks. These results showed that C stain was excellent on the fact of nutrients compared to other strains. Consequently, the result of this work gave the basic data that needed to develope the new strains.

• Food Science and Preservation
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• v.15 no.3
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• pp.367-376
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• 2008

This study was conducted to investigate 1he quality characteristics of 1he soybean anchovy sauces added with medicinal herbs, Saururu chinensis Baill. and Houttuynia cordata Thunb. and fermented for 4 months. The total nitrogen content of 1he soybean anchovy sauce increased with the fermentation time showing the highest values in the sauce with Houttuynia cordata Thunb.. The contents of total sugar and reduced sugar were high in the order of the sauces with Houttuynia cordata Thunb.(sauce T), with Saururu chinensis Baill.(sauce B), and control. The content of salt decreased much more in the sauces with medicinal herbs. After 4 months of fermentation, pH was lowered from 5.86 to 5.27 in control, to 5.38 and 5.54 in sauce B and sauce T, respectively. Generally the total aerobic bacterial count increased until 3 months of fermentation and then decreased, and the addition of medicinal hems reduced the count especially showing apparent reduction in the sauce T. During the fermentation, total protease activity generally increased with the highest value in the sauce T. In the changes of nucleotides and their related compounds, the contents of AMP, ADP, and ATP were increased and hypoxanthine decreased during the fermentation, and IMP produced after 3 months. The soybean anchovy sauce B had 1he highest IMP and the lowest hypoxanthine after 4 months. The content of total amino acids increased showing 177.1 mg% and 134.7 mg% in the sauce B and sauce T respectively compared with 171.2 mg% of control. The contents of glutamic acid and aspartic acid were 29.2 mg% in sauce B and 34.3 mg% in sauce T, which were higher compared with 25.9 mg% of control. The fermented soybean anchovy sauce had 1he functionality of ACE inhibition with 70.5% (control), 72.5% (sauce B) and 81.6% (sauce T). In the results of sensory evaluation, the sance T scored the highest and the sauce B was preferred to control.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.5
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• pp.500-505
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• 2017

The nucleotides and their related compounds, including ATP (adenosine triphosphate), ADP (adenosine diphosphate), AMP (adenosine monophosphate), IMP (inosine monophosphate), HxR (inosine) and Hx (hypoxanthine), were nearly identical in oysters Crassostrea gigas from the two culture methods. The K-value was lower than the threshold value such as 11.2-12.1. Although oysters have low amount of IMP, it was detected in this experiment. DPPH radical scavenging activity did not vary significantly with sample amounts (100, 300, and $500{\mu}g/mL$). DPPH (1,1-diphenyl-2-picryl-hydrazyl) radical scavenging activity was 76.0-80.7% compare with the ascorbic acid standard. Superoxide anion scavenging activity reached 49.3% in the rack-and-bag culture sample at $500{\mu}g/mL$. However, the reducing power and $Fe^{2+}$ chelating activity were very low compared with their respective standard. The oyster culture methods did not affect oyster quality in terms of antioxidant activities.

• Nuclear Engineering and Technology
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• v.52 no.8
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• pp.1777-1783
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• 2020

As a part of R&D work for the high intensity proton linac of China Accelerator Driven Sub-critical System project, a superconducting half-wave cavity with a frequency of 162.5 MHz and an optimal beta of 0.15 (HWR015) has been developed at Institute of Modern Physics (IMP), Chinese Academy of Sciences. In this paper, the design and test results will be described in detail. We introduced a new stiffening strategy for the HWR cavity, the simulation results show that the cavity has much lower frequency sensitivity coefficient (df/dp), Lorentz force detuning coefficient (KL), and can achieve more stable mechanical properties. The performance of the HWR cavity operated in cryostat will be also reported.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.22 no.5
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• pp.228-232
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• 1989

Katsuobushi has widely been used from olden times to prepare soup stock. This study was carried out to prepare stock of powdered Katsuobushi, and to examine the extractive conditions and the contribution of principal taste compounds to its characteristic taste. The extractive condition of powdered Katsuobushi in preparing stock was the most appropriate at $100^{\circ}C$ for 1 minute boiling water-steeping method in flavor, clearance of stock. From the chemical analysis and omission test, the principal taste-active components in $4\%$ solution powdered Katsuobushi under this extractive condition were nucleotides 93.6mg/100ml, free amino acids and imidazole dipeptides 41.3mg/100ml, and non-volatile organic acids 39.3mg/100l1 in order. IMP, inosine, AMP, histidine, anserine, taurine, carnosine and lactic acid were predominant among the detected compounds.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.7 no.3
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• pp.163-168
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• 1974

The present paper deals with the degradation of nucleotides in the muscle of sea mussel, Mytilus edulis, during drying. Three kinds of samples, raw, hot-air dried, and steamed-and-hot air dried were prepared and the contents of nucleotides were determined by ion exchange chromatography on columns of Dowex 1, X8. ATP and ADP were dominant in the raw muscle showed about $8{\mu}moles/g$, dry basis, respectively. The rate of degadation of ATP was very slow during drying compared with those of fish. The accumulation of ADP and AMP were observed during drying and the amount of total nucleotides (ATP+ADP+AMP) were not decreased remarkably by drying process. IMP was not detected in the all of the samples examined, however, the contents of inosine and hypoxanthine were increased during drying. In case of inosine contents, the hot-air dried sample marked an exceedingly high value equivalent to 8 times of the raw sample whereas steamed-and-hot air dried sample showed 2 times of raw samples.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.12
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• pp.1733-1738
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• 2017

Objective: Different dry-aging methods [traditional dry-aging (TD), simplified dry-aging (SD), and SD in an aging bag (SDB)] were compared to investigate the possible use of SD and/or SDB in practical situations. Methods: Sirloins from 48 Hanwoo cows were frozen (Control, 2 days postmortem) or dry-aged for 28 days using the different aging methods and analyzed for chemical composition, total aerobic bacterial count, shear force, inosine 5′-monophosphate (IMP) and free amino acid content, and sensory properties. Results: The difference in chemical composition, total aerobic bacterial count, shear force, IMP, and total free amino acid content were negligible among the 3 dry-aged groups. The SD and SDB showed statistically similar tenderness, flavor, and overall acceptability relative to TD. However, SDB had a relatively higher saleable yield. Conclusion: Both SD and SDB can successfully substitute for TD. However, SDB would be the best option for simplified dry-aging of low-marbled beef with a relatively high saleable yield.