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Studies on the Processing of Rapid- and Low Salt-Fermented Liquefaction of Anchovy(Engrulis japonica) (I) -Changes in Free Amino Acids during Fermentation and Quality Indices- (저식염 속성 멸치 발효액화물 가공에 관한 연구(I) -숙성 중 유리아미노산 변화 및 품질지표-)

  • Kang, Tae-Jung;Cho, Kyu-Ok;Park, Choon-Kyu
    • Journal of the Korean Society of Food Culture
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    • v.17 no.2
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    • pp.197-213
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    • 2002
  • In order to establish the processing condition of rapid- and low salt-fermented liquefaction of anchovy (Engrulis japonica), effect of temperature on crude enzyme activity of anchovy viscera, pretreatment conditions, and the minimum content of adding NaCl were investigated. The minimum limitation of NaCl content for anchovy liquefaction was 10%. Sample A(water adding, heating, adding 10% NaCl): chopped whole anchovy adding 20% water and then heating for 9 hrs at $50^{\circ}C$ and then adding 10% NaCl and then fermented at room temperature$(8-29^{\circ}C)$ for 180 days. Sample B(water adding, heating, adding 13% NaCl): chopped whole anchovy adding 20% water and then heating for 9 hrs at $50^{\circ}C$ and then adding 13% NaCl and then fermented at room temperature for 180 days. Sample C(adding 13% NaCl): chopped whole anchovy and then adding 13% NaCl and then fermented at room temperature for 180 days. Sample D(adding 17% NaCl): whole anchovy adding 17% NaCl and then fermented at room temperature for 180 days. The content of free amino acids such as aspartic acid, serine and threonine fluctuated severely according to the pretreatment methods. Possibly they might be recommend quality indices of standardization for salt-fermented liquefaction of anchovy. As for the relation between fermentation period(X) and individual free amino acid(Y), five kinds of free amino acids such as glutamic acid, valine, glycine, lysine, and alanine showed highly significant in their coefficient of determination in most of samples. They might be recommend as quality indices for salt-fermented liquefaction of anchovy during fermentation. The difference of taste between products of the rapid- and low salt-fermented liquefaction and the traditional salt-fermented liquefaction were caused by their composition of the free amino acids ratios, in which were umami, sweet, and bitter taste in the extracts of anchovy during fermentation. The appropriate fermentation period of the sample A was shorten 30 days than the sample B and 60 days than the samples C and 90 days than the sample D in the processing of anchovy.

Changes in Lipid Components of Gae-bul, Urechis unicinctus, During Hot-air Drying (개불 건조중의 지방질성분의 변화)

  • Oh, Kwang-Soo;Chung, Young-Hoon;Lee, Tae-Hun;Ahn, Chang-Bum;Lee, Eung-Ho
    • Korean Journal of Food Science and Technology
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    • v.18 no.2
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    • pp.153-157
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    • 1986
  • Changes in lipid components of Gae-bul, Urechis unicinctus, during hot-air drying ($40^{\circ}C$, 7 hrs) were studied. Raw sample contained 1.3% total lipid (TL) which consisted of 35.1% neutral lipid (NL), 18.0% glycolipid (GL) and 46.9% phospholipid (PL), and dried sample contained 5.3% TL which consisted of 51.8% NL, 20.5%GL and 27.7% PL. There were about 40% decrease in PL content and a slight increase in NL content during drying. The NL of raw sample mainly consists of triglyceride (TG, 39.8%), free sterol (FS, 39.6%), free fatty acid (FFA, 12.2%). and also identified diglyceride (DG), monoglyceride and esterified sterol and hydrocarbon in less quantify. The percent of TG and FS decreased, while that of FFA and DG increased during drying. And main components in the PL were phosphatidyl choline (PC,45.6%), phosphatidyl ethanolamine (PE,34.8%), and followed by phosphatidyl serine (PS) and an unknown substance. In the components of PL, PE, PS and PC decreased slightly in order during drying. And major fatty acids of raw and dried samples were generally 16:0, 18: 1, 18:3, and 20:5. The content of the polyenoic acid such as 20:5 decreased. while the saturated acid increased slightly during drying.

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Some Quality Changes of Dried Loach (Misgurnus-mizolepis) by Microwave (2,450 MHz) Heating (Micro파(波) 처리(處理)에 따른 건(乾)미꾸라지의 품질변화(品質變化))

  • Park, Il-Woong;Hong, Jai-Sik;Kim, Jong-Bae
    • Korean Journal of Food Science and Technology
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    • v.18 no.6
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    • pp.413-420
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    • 1986
  • This study was attemtped to improve the conventional processing method and to establish the basic data for evaluating the product suitabilities of dried loach. The semidressed raw material were salted in 15% NaCl solution for 15 minutes and dried to contain about 44% of water, and then heated about 10 minutes at $80^{\circ}C$ controlled by microwave (2,450 MHz). The moisture content of monolayer value for the product showed 5.34% and its water activity was 0.28. The optimum relative humidity for the storage was recognized to be from 32% to 44%. The average shelf life around the year of the Nylon-PVC-PE $(40\;{\mu})$ packed product in domestic circulation market was estimated as 207.4 days. In comparison with raw material, the contents of the major amino acids, glutamic acid, alanine and valine in the product were shown to be slightly increased, while the level of lysine, aspartic acid and methionine were slightly decreased. The contents of saturated fatty acids and oleic acid were shown to be slightly increased, while the other fatty acids tended to be slightly decreased.

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Changes Observed in Doenjang (Soybean Paste) Containing Fermented-Rhus verniciflua Extract During Aging (발효옻 추출물 첨가 된장의 숙성에 따른 변화)

  • Choi, Han-Seok;Kang, Ji-Eun;Jeong, Seok-Tae;Kim, Chan-Woo;Kim, Myung-Kon
    • Korean Journal of Food Science and Technology
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    • v.47 no.5
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    • pp.599-607
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    • 2015
  • Fermented-Rhus verniciflua (FRV) extract is increasingly used in fermented soy products, fermented vinegars, and certain alcoholic beverages. In this study, we investigated the effects of FRV extract on the physicochemical properties of doenjang (soybean paste). Addition of FRV extract to doenjang resulted in a 28.2-45.4% increase in the amino acid content and a 1.3- to 1.5-fold increase in the concentrations of glutamic acid, which imparts a savory flavor to doenjang. The concentration of biogenic amine (BA) of the sample containing the extract was 5.3-52.6% lower than that of the control. The major components of BA included tyramine (55.1-74.6%), followed by putrescine, spermidine, tryptamine, and cadaverine, in decreasing concentrations. The organic acid concentration of the sample containing the extract was 1.2-1.3-fold higher than that of the control. The total free sugar concentration was 163.4 mg/100 g in the control and 206.6-276.8 mg/100 g in the supplemented sample, showing a 1.3- to 1.9-fold increase as the addition of the extract.

PCR-SSCP Polymorphism of Inhibin ${\beta}_A$ Gene in Some Sheep Breeds

  • Chu, M.X.;Xiao, C.T.;Fu, Y.;Fang, L.;Ye, S.C.
    • Asian-Australasian Journal of Animal Sciences
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    • v.20 no.7
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    • pp.1023-1029
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    • 2007
  • Inhibins participate in the regulation of pituitary follicle-stimulating hormone synthesis and secretion, follicular maturation and steroidogenesis in the female. Inhibin ${\beta}_A$ gene (INHBA) was studied as a candidate gene for the prolificacy of sheep. Single nucleotide polymorphisms of the entire coding region and partial 3' untranslated region of INHBA were detected by PCR-SSCP in two high fecundity breeds (Small Tail Han and Hu sheep) and six low fecundity breeds (Dorset, Texel, German Mutton Merino, South African Mutton Merino, Chinese Merino and Corriedale sheep). Only the PCR products amplified by primers 3, 4 and 5 displayed polymorphisms. For primer 3, genotype CC was only detected in Chinese Merino sheep, genotype AA was detected in the other seven sheep breeds. Genotype BB was only detected in Hu sheep. Only Hu sheep displayed polymorphism. Eight or four nucleotide mutations were revealed between BB or CC and AA, respectively, and these mutations did not result in any amino acid change. For primer 4, genotypes EE, EG and GG were detected in Dorset and German Mutton Merino sheep, genotypes EE, EF and FF were detected in Chinese Merino sheep, only genotype EE was detected in the other five sheep breeds. Only Dorset, German Mutton Merino and Chinese Merino sheep displayed polymorphism. Sequencing revealed one nucleotide mutation ($114G{\rightarrow}A$) of exon 2 of INHBA gene between genotype FF and genotype EE, and this mutation did not cause any amino acid change. Another nucleotide change ($143C{\rightarrow}T$) was identified between genotype GG and genotype EE, and this mutation resulted in an amino acid change of $serine{\rightarrow}leucine$. For primer 5, genotypes KK and KL were detected in German Mutton Merino and Corriedale sheep, genotypes KK, LL and KL were detected in the other six sheep breeds. Genotype MM was only detected in Hu sheep. All of these eight sheep breeds displayed polymorphism. Sequencing revealed one nucleotide mutation ($218A{\rightarrow}G$) of exon 2 of the INHBA gene between genotype LL and genotype KK, and nine nucleotide mutations between genotype MM and genotype KK. These mutations did not alter amino acid sequence. The partial sequence (395 bp for exon 1 and 933 bp for exon 2) of the INHBA gene in Small Tail Han sheep (with genotype KK for primer 5) was submitted into GenBank (accession number EF192431). Small Tail Han sheep displayed polymorphisms only in the fragment amplified by primer 5. The Small Tail Han ewes with genotype LL had 0.53 (p<0.05) or 0.63 (p<0.05) more lambs than those with genotype KL or KK, respectively. The Small Tail Han ewes with genotype KL had 0.10 (p>0.05) more lambs than those with genotype KK.

Purification and Characterization of a Novel Extracellular Thermostable Alkaline Protease from Streptomyces sp. M30

  • Xin, Yan;Sun, Zhibin;Chen, Qiongzhen;Wang, Jue;Wang, Yicheng;Luogong, Linfeng;Li, Shuhuan;Dong, Weiliang;Cui, Zhongli;Huang, Yan
    • Journal of Microbiology and Biotechnology
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    • v.25 no.11
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    • pp.1944-1953
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    • 2015
  • A novel alkaline protease from Streptomyces sp. M30, SapHM, was purified by ammonium sulfate precipitation, hydrophobic interaction chromatography, and DEAE-Sepharose chromatography, with a yield of 15.5% and a specific activity of 29,070 U/mg. Tryptic fragments of the purified SapHM were obtained by electrospray ionization quadrupole time-of-flight mass spectrometry. Nucleotide sequence analysis revealed that the gene sapHM contained 1,179 bp, corresponding to 392 amino acids with conserved Asp156, His187, and Ser339 residues of alkaline protease. The first 24 amino acid residues were predicted to be a signal peptide, and the molecular mass of the mature peptide was 37.1 kDa based on amino acid sequences and mass spectrometry. Pure SapHM was optimally active at 80℃ in 50 mM glycine-NaOH buffer (pH 9.0), and was broadly stable at 0-50℃ and pH 4.0-9.0. The protease relative activity was increased in the presence of Ni2+, Mn2+, and Cu2+ to 112%, 113%, and 147% of control, respectively. Pure SapHM was also activated by dimethylformamide, dimethyl sulfoxide, Tween 80, and urea. The activity of the purified enzyme was completely inhibited by phenylmethylsulfonyl fluoride, indicating that it is a serine-type protease. The Km and Vmax values were estimated to be 35.7 mg/ml, and 5 × 104 U/mg for casein. Substrate specificity analysis showed that SapH was active on casein, bovine serum albumin, and bovine serum fibrin.

Identification and Characterization of Protein Encoded by orf382 as $\small{L}$-Threonine Dehydrogenase

  • Ma, Fei;Wang, Tianwen;Ma, Xingyuan;Wang, Ping
    • Journal of Microbiology and Biotechnology
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    • v.24 no.6
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    • pp.748-755
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    • 2014
  • In the genome annotation of Escherichia coli MG1655, the orf382 (1,149 bp) is designated as a gene encoding an alcohol dehydrogenase that may be Fe-dependent. In this study, the gene was amplified from the genome by PCR and overexpressed in Escherichia coli BL21(DE3). The recombinant $6{\times}$His-tag protein was then purified and characterized. In an enzymatic assay using different hydroxyl-containing substrates (n-butanol, $\small{L}$-threonine, ethanol, isopropanol, glucose, glycerol, $\small{L}$-serine, lactic acid, citric acid, methanol, or $\small{D}$-threonine), the enzyme showed the highest activity on $\small{L}$-threonine. Characterization of the mutant constructed using gene knockout of the orf382 also implied the function of the enzyme in the metabolism of $\small{L}$-threonine into glycine. Considering the presence of tested substrates in living E. coli cel ls and previous literature, we believed that the suitable nomenclature for the enzyme should be an $\small{L}$-threonine dehydrogenase (LTDH). When using $\small{L}$-threonine as the substrate, the enzyme exhibited the best catalytic performance at $39^{\circ}C$ and pH 9.8 with $NAD^+$ as the cofactor. The determination of the Km values towards $\small{L}$-threonine (Km = $11.29{\mu}M$), ethanol ($222.5{\mu}M$), and n-butanol ($8.02{\mu}M$) also confirmed the enzyme as an LTDH. Furthermore, the LTDH was shown to be an ion-containing protein based on inductively coupled plasma-atomic emission spectrometry with an isoelectronic point of pH 5.4. Moreover, a circular dichroism analysis revealed that the metal ion was structurally and enzymatically essential, as its deprivation remarkably changed the ${\alpha}$-helix percentage (from 12.6% to 6.3%).

Acinetobacter pullorum sp. nov., Isolated from Chicken Meat

  • Elnar, Arxel G.;Kim, Min-Gon;Lee, Ju-Eun;Han, Rae-Hee;Yoon, Sung-Hee;Lee, Gi-Yong;Yang, Soo-Jin;Kim, Geun-Bae
    • Journal of Microbiology and Biotechnology
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    • v.30 no.4
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    • pp.526-532
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    • 2020
  • A bacterial strain, designated B301T and isolated from raw chicken meat obtained from a local market in Korea, was characterized and identified using a polyphasic taxonomic approach. Cells were gram-negative, non-motile, obligate-aerobic coccobacilli that were catalase-positive and oxidase-negative. The optimum growth conditions were 30℃, pH 7.0, and 0% NaCl in tryptic soy broth. Colonies were round, convex, smooth, and cream-colored on tryptic soy agar. Strain B301T has a genome size of 3,102,684 bp, with 2,840 protein-coding genes and 102 RNA genes. The 16S rRNA gene analysis revealed that strain B301T belongs to the genus Acinetobacter and shares highest sequence similarity (97.12%) with A. celticus ANC 4603T and A. sichuanensis WCHAc060041T. The average nucleotide identity and digital DNA-DNA hybridization values for closely related species were below the cutoff values for species delineation (95-96% and 70%, respectively). The DNA G+C content of strain B301T was 37.0%. The major respiratory quinone was Q-9, and the cellular fatty acids were primarily summed feature 3 (C16:1 ω6c/C16:1 ω7c), C16:0, and C18:1 ω9c. The major polar lipids were phosphatidylethanolamine, diphosphatidyl-glycerol, phosphatidylglycerol, and phosphatidyl-serine. The antimicrobial resistance profile of strain B301T revealed the absence of antibiotic-resistance genes. Susceptibility to a wide range of antimicrobials, including imipenem, minocycline, ampicillin, and tetracycline, was also observed. The results of the phenotypic, chemotaxonomic, and phylogenetic analyses indicate that strain B301T represents a novel species of the genus Acinetobacter, for which the name Acinetobacter pullorum sp. nov. is proposed. The type strain is B301T (=KACC 21653T = JCM 33942T).

The Nutritional Components of Olive Flounder (Paralichthys olivaceus) Fed Diets with Yuza (Citrus junos Sieb ex Tanaka) (유자 첨가 사료로 사육된 넙치의 영양성분)

  • Kim, Heung-Yun;Kim, Eun-Heui;Kim, Do-Hyung;Oh, Myung-Joo;Shin, Tai-Sun
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.42 no.3
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    • pp.215-223
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    • 2009
  • This study was conducted to investigate the effect of diets supplemented with different levels (0, 2.5, 5.0, and 7.5%) of yuza (Citrus junas Sieb ex Tanaka) on nutritional composition of olive flounder. Four groups of fish (242.2$\pm$14.2 g) were fed to apparent satiation twice daily for 4 months. There were no significant differences in proximate composition among the treatment groups (P<0.05). Vitamin C content in flounder muscle was higher in the yuza-added groups than in the control group, and the content among the treatment groups increased as amount of yuza added to diets increased (P<0.05). Of the eight organic acids in flounder muscle, lactic acid was predominant, followed by oxalic acid, succinic-acid, tartaric acid, and acetic acid. Flounders fed 2.5% yuza diet had the highest lactic acid content of all treatments. Four sugars were found in all groups and glucose was the major sugar. Glucose and ribose were detected as the highest sugars in the 2.5% treatment, while maltose and galactose were the dominant sugars in the 5.0% treatment. The abundant fatty acids in fed flounders were 22:6n-3 (DHA), 16:0, and l8:1n-9, which were composed of over 60% of total fatty acids. The control and the 7.5% treatment group had higher 22:6n-3 (DHA) content than the other groups. Major amino acids in samples were glutamic acid, aspartic acid, lysine, leucine, valine, arginine, and alanine. The 2.5% yuza treatment had the highest content of total amino acids and essential amino acids. There were little differences in the free amino acid compositions among the treatments. However, taurine was the predominant amino acid and made up over 47% of total free amino acids. The 2.5% added yuza group contained higher amount of sweet amino acids such as alanine, serine, proline, glycine than the other groups. The addition of yuza to diet of olive flounder had no or little effect on the nutritional components of olive flounder except for vitamin C. However, the 2.5% yuza added group had the highest nutritional values of the treatment groups.

Inhibition of Human Leukocyte Cathepsin G by NSAIDs (Non-Steroidal Anti-Inflammatory Drugs) (NSAIDs (Non-Steroidal Anti-Inflammatory Drugs)에 의한 사람 중성구 Cathepsin G의 활성도 억제)

  • Bae, Sung-Jun;Ghim, Sa-Youl;Kang, Koo-Il
    • The Korean Journal of Pharmacology
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    • v.26 no.1
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    • pp.51-54
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    • 1990
  • Human leukocyte cathepsin-Gs are active participant in the active phase of inflammations like rheumatoid arthritis, emphysema and glomerular injury. Non-steroidal anti-inflammatory drugs (NSAIDs) are widely used for treatment of these inflammatory diseases. Mechanism of action of NSAIDs for treatment of inflammatory diseases, especially like rheumatoid arthritis, are known as the inhibitors of prostaglandin synthesis. Inhibitions of the activities of human leukocyte cathepsin-Gs by non-steroidal anti-inflammatory drugs, however, were not same as the known pharmacological effects (inhibition of cyclooxygenase) of these drugs. Among them, especially, sulindac, salicylate, phenylbutazone, oxyphenbutazone, and salicyluric acid inhibited human leukocyte cathepsin-Gs effectively. $IC_{50}s$ of each drug were 4.3mM, 14.3mM, 6.5mM, 11mM and 15mM respectively. The drugs which have same chemical structure and same degree of inhibition effect on cyclooxygenase showed different degree or no effect on inhibition of cathepsin G. These inhibition effect might be, beside of inhibition of cyclooxygenase in the prostaglandin synthesis pathway, another benefitial antiinflammatory effect of NSAIDs by direct protection against tissue destruction in inflammatory diseases.

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