• Microbiology and Biotechnology Letters
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• v.10 no.4
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• pp.283-288
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• 1982

Trypsin inhibitor produced by Streptomyces sp. was investigated its reactive characteristics against trypsin. The mode of inhibition against trypsin was mixed type of non-competitive and competitive with casein, and enzyme-inhibitor complex was formed rapidly. The inhibitory activity was increased by the addition of isoleucine and depressed by silver, mercuric or cupric ion. And when egg albumin or hemoglobin was used as substrate for trypsin, the inhibition ratio was changed. The inhibitor inhibited coagulation of blood of bovine.

• Journal of Nutrition and Health
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• v.10 no.4
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• pp.97-103
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• 1977

Changes of free amino acids as taste compounds during the fermentation of oyster were analyzed by amino acid autoanalyzer. In fresh oyster, taurine, glutamic acid and alanine were abundant amino acids and the amounts of taurine (731mg%, on moisture and salt free base), glutamic acid (365mg%) and alanine (345.4mg% ) were 63.8% of the total free amino acids. Cystine, isoleucine, phenylalanine, leucine and histidine were detected as less abundant free amino acids and the amount of those amino. acids ranged from 5. 5mg% (cystine) to 32.9mg% (histidine). The free amino acids analyzed in this experiment were not changed in composition hut changed in amounts during 124 days of fermentation. Aspartic acid and leucine were continually increased during 124 days of fermentation. Lysine, histidine, threonine, serine, glutamic acid, tyrosine and phenyalanine were increased unlit 68 days of fermentation and than decreased gradually. The increase of arginine, glycine, valine and isoleucine were fluctuated. Taurine were dramatically decreased during the 124 days of fermentation. It is believed that glutamic acid, alanine, lecuine, serine, Iysine and threonine play an important role as taste compounds in fermented oyster because those amino acids were most abundant in fermented oyster.

• Journal of the Korean Home Economics Association
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• v.23 no.4
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• pp.55-60
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• 1985

This study was carried out to compare the change of free amino acid content in the radish Kimchi added with anchovy pickle sauce with that added with 15% NaCl solution during 30 days fermentation. RESULTS : 1. During the fermentation, the pH of both sample A and B showed the highest values of 7.3 and 7.1, respectively, and then both decreased continually to the lowest value of 4.2 at the 30th day. 2.The salinity in the juice of sample A was higher than that of sample B in all the steps during fermentation, accompanied with a slight decrease of the salinity in both cases with time elapsed. 3. The free amino-type nitrogen content of sample A was nearly duplicated in the final step than in the initial one,while that of sample B showed no significant changes in all the processing period. 4. The free amino acids detected in the both samples were aspartic acid, threonine, serine, proline, glutamic acid, glycine, alanine, tyrosine, cysteine, valine, methinonine, isoleucine, leucine, phenylalanine, $\gamma-aminobutyrix acid(\ulcorner), ornithine, lysine, histidine and arginine. 5. The amounts of proline, arginine were the highest in all free amino acids during fermentation, and tasty components of radish Kimchi seemed to relate to glutamic acid, alanine, isoleucine, leucine, phenylalanine, more deliciousness of Kimchi A and B seemed to derive from amino acids of anchovy pickle sauce added to Kimci A, such as alanine, valine, phenylalanine, lysine.

• Journal of the Korean Wood Science and Technology
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• v.33 no.5 s.133
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• pp.92-98
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• 2005

This study was performed to get the basic information concerned to the optimum culture condition of Inonotus obliquus. Several solid media, PDA, MEA and Czapek-Dox, and three liquid media were adopted for the in vitro cultivation. Some main features of the fungal morphological characteristics under cultivation conditions were observed and described. Preliminary results showed that appearance of the mycelial mat, hyphal size and substrate pigmentation differed according to the media. The PDA medium was the most favorable substrate for the growth on solid culture, followed by MEA and Czapek-Dox media. Concerned to the addition of amino acids, 5 amino acids, such as alanine, alginine, isoleucine, leucine and threonine, enhanced to the mycelial growth. Isoleucine was shown the best fungal growth. An important morphological hyphal structure for the fungus, the setae, was found in abundance and diverse its shape and size. In liquid culture, fresh potato broth was the best growth stimulant of the fungus, followed by Malt extract and potato broth. Addition of yeast extract to the liquid media had improved the biomass, but not laccase production.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.12 no.4
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• pp.241-243
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• 1979

Coral damselfish (demoiselle), Chromis notatus, has been one of the most tasty sea foods in Jeju-Do, Korea, The free amino acids in tile extracts of Chromis notatus were analysed by amino acid autoanalyser. In the extracts, taurine, lysine, glycine and alanine were abundant, holding $30.3\%,\;22.7\%,\;16.0\%\;,\;11.5\%$ of total amino acid content, respectively and followed threonine, glutamic acid and serine, in order. While methionine, histidine, leucine, isoleucine, valine were poor and aspartic acid and proline were trace in content.

• Fisheries and Aquatic Sciences
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• v.14 no.4
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• pp.283-288
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• 2011

The jellyfish Nemopilema nomurai was hydrolyzed with papain and a novel dipeptide purified via ultrafiltration, gel filtration chromatography with Sephadex LH-20, and reverse phase chromatography using $C_{18}$ and $C_{12}$ columns. The IR, 1H NMR, 13C NMR, and MS spectrometer analyses showed that the dipeptide comprised tyrosine-isoleucine (Tyr-Ile). The $IC_{50}$ and $K_i$ values were $6.56{\pm}1.12$ and $3.10{\pm}0.28\;{\mu}M$, respectively, indicating competitive inhibition of angiotensin-I-converting enzyme (ACE). As a novel ACE-inhibitory active peptide, Tyr-Ile may have potential for use in antihypertensive therapy.

• Korean Journal of Food Science and Technology
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• v.21 no.3
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• pp.404-408
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• 1989

This study was conducted to confirm amino acids from the filterate of pollen treated by purified enzyme of bee larva gut for improving pollen food. The larva gut enzyme were purified by ammonium sulfate, ethanol and Sephadex gel filtration. The filterate of pollen treated with enzyme purified by ammonium sulfate showed the highest amount of amino acids. The amount of amino acids of the filterate from which the pollen was fermented with natural contaminants is 5.5 times as much as the pollen which was not fermented. The filterate of pollen treated with enzyme of bee larva gut contained eighteen different amino acids as follows : aspartates, glutamate, serine, glycine, histidine, arginine, threonine, alanine, proline , tyrosine, valine, methionine, cysteine, isoleucine, leucine, phenylalanine, lysine and trytophane.

• Journal of the Korean Society of Food Science and Nutrition
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• v.15 no.3
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• pp.249-252
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• 1986

This quantitative analysis was carried out in order to investigate the isolation and identification of total amino acids and free sugars in Lycii fructus by using amino acid autoanalyzer and HPLC. 17 kinds of amino acids were analyzed by amino acid autoanalyzer, that is, aspartic acid, proline, glyclne, analine, cystine, valine, methionine, isoleucine, leucine, tyrosine, phenyla lanine, histidine, lysine, arginine, threonine, serine and glutamic acid. Threonine (3,745mg/100g) was the richest among them and total amounts of the essential amino acid, which was 53.93% of total amino acids, was 10,773mg/100g. Free sugars isolated by HPLC wet·e glucose, fructose and saccharose.

• The Korean Journal of Zoology
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• v.33 no.2
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• pp.166-174
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• 1990

Gallena mellonella L. was parasitized by the pupal parasitoid, Brachymerica lasus Walker in the laboratory. Haemolymph total protein and carbohydrate concentrations from the hosts parasitized by B. lasus decreased within 1st day following parasitization. However, haemolymph total free amino adds, glycine, proline, arginine, isoleucine, phenylalanie, leucine, valine, glutamk acid, histidine, serine, and tyrosine increased and free amino acids decreased were threonine, aspartic acid, methionine, cysteine, alanine, and lysine.

• KSBB Journal
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• v.20 no.5 s.94
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• pp.376-382
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• 2005

Avermectin (AVM) $B_{1a}$ produced by Streptomyces avermitilis via polyketide pathway is a secondary metabolite with powerful anthelmintic and insecticidal activities, thus being used as an efficient agent in the field of agriculture and animal health. It has been reported that a precursor for AVM $B_{1a}$ biosynthesis was isoleucine and the biosynthetic pathway of AVM $B_{1a}$ was closely similar to that of fatty acid. Based on understanding of the biosynthetic pathway of AVM $B_{1a}$, we intended to screen various mutants resistant against O-methyl threonine (OMT), an isoleucine-anti metabolite, and/or mutants resistant against p-fluoro phenoxy acetic acid (pFAC), an inhibitor of fatty acid biosynthesis. It was inferred that these mutants could produce AVM $B_{1a}$ more efficiently, due to the acquired capability of not only overproducing isoleucine intracellularly but also channelling metabolized carbon-sources into the polyketide pathway, thus leading to enhanced biosynthesis of AVM $B_{1a}$. The resulting mutant (PFA-1 strain) resistant against 100 ppm of pFAC was able to produce approximately 42 fold higher amount of AVM $B_{1a}$ compared to the parallel mother strain (4,200 vs. 100 units/l). In addition, through the process of continuous strain improvement program carried out by gradually increasing the OMT concentration, it was possible to obtain a more attractive mutant with greater AVM $B_{1a}$ production capacity (9,000 units/l). Notable was that significantly higher producer (12,000 units/l) could be selected through further screening of the resistant mutants, this time, to even higher concentration of PFAC. Meanwhile, through the analysis of AVM Bla production histograms (i.e., number of strains according to their AVM $B_{1a}$ biosynthetic ability) for the earlier strains in comparison with the high producers having the characteristics of resistance to OMT and pFAC, it was found that production stability of the high-yielding producers were remarkably improved, as demonstrated by the fact that larger proportion of the mutated strains had greater capability of AVM $B_{1a}$ biosynthesis ($71\%$ in the range between 5,000 and 7,000 units/L; $47\%$ in the range between 6,000 and 7,000 units/l). Based on these consequences, it was concluded that the rational screening strategy based on the understanding of the biosynthetic pathway of AVM $B_{1a}$ was very effective in obtaining high-yielding mutants with the features of enhanced production stability.