• Journal of Microbiology and Biotechnology
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• v.14 no.6
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• pp.1318-1323
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• 2004

This study describes the purification and characterization of a novel antihypertensive angiotensin 1­converting enzyme (ACE) inhibitory peptide from Saccharomyces cerevisiae. Maximal production of the ACE inhibitor from Saccharomyces cerevisiae was obtained from 24 h of cultivation at $30^{\circ}C$ and its ACE inhibitory activity was increased by about 1.5 times after treatment of the cell-free extract with pepsin. After the purification of ACE inhibitory peptides with ultrafiltration, Sephadex G-25 column chromatography, and reverse-phase HPLC, an active fraction with an $IC_{50}$ of 0.07 mg and $3.5\%$ yield was obtained. The purified peptide was a novel decapeptide, showing very low similarity to other ACE inhibitory peptide sequences, and its amino acid sequence was Tyr-Asp-Gly-Gly-Val-Phe-Arg-Val-Tyr-Thr. The purified inhibitor competitively inhibited ACE and also showed a clear antihypertensive effect in spontaneously hypertensive rats (SHR) at a dosage of 1 mg/kg body weight.

• Journal of Microbiology and Biotechnology
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• v.10 no.2
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• pp.244-250
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• 2000

An ${\alpha}-glucosidase$ gene (aglA) from thermophilic Bacillus sp. DG0303 was cloned, sequenced, and expressed in Escherichia coli. The aglA was localized to the 2.1-kb PvuI-XmnI region within the 5.9-kb DNA insert of the gybrid plasmid pAG1. The gene consisted of an open reading frame of 1,686 bp with an unusual GTG initiation codon and TGA termination codon. The amino acid sequence deduced from the nucleotide sequence predicted a protein of 562 amino acid residues with a M, of 66,551 dalton. A comparative amino acid sequence analysis revealed that DG0303 ${\alpha}-glucosidase$ is related to bacillary oligo-1, 6-glucosidases. The Bacillus sp. DG0303 ${\alpha}-glucosidase$ showed a high sequence identity (36-59%) to the B. flavocaldarius, B. cereus, and B. thermoglucosidasius oligo-1, 6-glucosidases. The number of prolines in theses four ${\alpha}-glucosidases. was observed to increase with increasing thermostability of these enzymes. The cloned ${\alpha}-glucosidase was purified from E. coli $DH5{\alpha}$ bearing pAG1 and characterized. The recombinant enzyme was identical with the native enzyme in its optimum pH and in its molecular mass, estimated by sodium dodecy1 sulfate-polyacrylamide gel electrophoresis. The temperature optimum of the cloned ${\alpha}-glucosidase$ was lower than that of the native enzyme.

• KSBB Journal
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• v.9 no.1
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• pp.40-47
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• 1994

A simplified mathematical model for the production of high-purity fructo-oligosaccharides by the mixed-enzyme system of fructosyl transferees and glucose oxidase was proposed and compared with the experimental results. The kinetic parameters including $K_m,\;V_{max}\;and\;K_{iG}$ were estimated at $40^{\circ}C$, in which $K_m$, values decreased and $K_{iG}$ and $V_{max}$ values increased compared with those of fructosyl transferees alone. The kinetics of the mixed-enzyme system was successfully described in the form of Michaelis-Menten equations. At the reasonable sucrose concentrations tested, the simulated sugar profiles were of good agreement with the experimental ones.

• Applied Microscopy
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• v.24 no.4
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• pp.41-51
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• 1994

The topology of the enzyme has been investigated by biochemical studies including chemical labeling and cross linking. Thirteen subunits(polypeptides) of the cytochrome-c-oxidase have localistic characteristics of existing in the matrix side or cytoplasmic side in the mitochondria. In order to observe the distribution of the enzyme subunit on the mitochondria membrane, immunogold-labeling methods were employed. Antibody was obtained from the serum of immunized rabbit with enzyme subunit antigen which was obtained from cytochrome-c-oxidase of the beef heart muscle mitochondria. Beef heart muscle tissue as a tissue antigen was stained with immunized rabbit IgG and protein A gold complex. Electron microscopy has identified the existance of cytochrome-c-oxidase subunit $Mt_I,\;Mt_{II}\;and\;Mt_{III}$ on the membrane of cristae and outer chamber of mitochondria and the subunit $C_{IV}$ on the membrane of cristae and matrix of mitochondria. Particularly, the subunit $C_{IV}$ was also observed to exist in the sarcoplasm of muscle tissue.

• Journal of Chest Surgery
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• v.15 no.4
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• pp.460-466
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• 1982

A analysis of CPK & LDH Isoenzyme was done on the consecutive patients undergoing thoracic operations from July 1982 to October 1982 in the Department of Thoracic and Cardiovascular Surgery, Capital Armed Forces General Hospital. Eighteen patients were analysed by three groups, such as open heart surgery [group A], major thoracic operation [group B] , minor thoracic operation group [group C]. In all patients serial determination of total level and Isoenzyme of CPK, LDH wad done on preoperative operative and up to 8th post-operative day, The results obtained are as follows. 1. The average value of serum CPK before the operation was 61 IU/L. The value of serum CPK was increased following the operation mainly MM portion and reached to the maximal level of 536107 IU/L in A group 1200191 IU/L in B group, 306150 IU/L in C group on the first postoperative day. The enzyme activity was gradually decreased thereafter and returned to the normal range on the 3rd or 4th day after the operation. 2. The average value of serum LDH before the operation was found to be 83 IU/L. The value was increased during the operation and reached to the maximal level of 481108 IU/L in group A, 14827 I U/L in group B, 10035 IU/L in group C on the second day after the operation. The enzyme activity was gradually decreased thereafter and returned to the normal range on the seventh day after the operation. The enzyme activity was dependent to the duration of operation, severity of muscle damage, type of thoracotomy, effect of extracorporeal circulation, state of disease.

• Microbiology and Biotechnology Letters
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• v.23 no.4
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• pp.446-453
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• 1995

$\alpha $-Arabinofuranosidase was produced by E. coli HB101 haboring the recombinant plasmid pKMG11 which contained the arfI gene of Bacillus stearothermophilus. The maximum production of the enzyme was observed when E. coli HB101 cells were grown at 37$\circ$C for 20 hours in the medium containing 0.5% arabinose, 1.0% tryptone, 0.5% yeast extract, and 1% NaCl. The $\ALPHA $-arabinofuranosidase produced was purified to homogeneity using a combination of 20-50% ammonium sulfate precipitation, DEAE-Sepharose CL-6B ion exchange column chromatography and Sepharose 6B-100 gel filtration. The purified enzyme was most active at 55$\circ$C and pH 6.5. The K$_{m}$ and V$_{max}$ values of the enzyme on $\rho $-nitrophenyl-$\alpha $-arabinofuranoside was determined to be 2.99 mM and 0.43 $\mu $mole/min (319.74 $\mu $mole/min/mg), respectively. The pI value was 4.5. The molecular weight of the native protein was estimated to be 289 kDa. The SDS-polyacrylamide gel clectrophoresis analysis suggested that the functional protein was a trimer of the 108 kDa identical subunits. The N-terminal amino acid sequence of the a-arabinofuranosidase was identified as X-Ser-Thr-Ala-Pro-Arg( \ulcorner )-Ala-Thr-Met-Val-Ile-Asp-X-Ala-Phe.

• YAKHAK HOEJI
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• v.25 no.4
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• pp.145-151
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• 1981

The effect of ginseng methanol extract on hepatic drug metabolizing enzyme in rat was investigated. The ginseng methanol extract (100mg/kg) was administered orally to Sprague Dawley rats for 7days and the contents of cytochrome $P_{450}$ and NADPH cytochrome c reductase in liver were measured by the method of Stanton et al. and Mazel respectively. The content of liver cytochrome $P_{450}$ and NADPH cytochrome c reductase in the rats treated with ginseng methanol extract (100mg/kg) were increased by 21.9% and l6.6% respectively and their increases were statistically significant. Single i.p. injection of phenobarbital (100mg/kg) to the rats produced approximately 25% increase in cytochrome $P_{450}$ content in this investigation and further stimulation was produced in the rats pretreated with ginseng methanol extract (100mg/kg). On the other hand, single i.p. injection of 95% $CCl_{4}$ (0.5ml/kg) showed 29% decrease in cytochrome $P_{450}$ content and 10.5% decrease in NADPH cytochrome c reductase activity. The degree of inhibition of cytochrome $P_{450}$ content in the rats pretreated with ginseng methanol extract (100mg/kg) was similar to that observed in the $CCl_{4}$ alone treated group, but NADPH cytochrome c reductase activity was increased by 65% in the rats pretreated with ginseng methanol extract (100mg/kg). These results suggest that ginseng is the hepatic drug metabolizing enzyme inducing agent in the rat and the effect is similar to phenobarbital.

• Journal of Animal Science and Technology
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• v.62 no.6
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• pp.933-947
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• 2020

This study was conducted to develop an effective heparin extraction method by using low-cost and highly effective enzymes from six pig by-products (liver, lung, heart, stomach, small intestine, and large intestine), and analyze their bioavailability. Low-cost and highly effective enzymes (alkaline-AK and papain) and a common enzyme (trypsin) were used for the heparin extraction. The angiotensin I- converting enzyme (ACE) inhibitory activity and the antimicrobial activity of extracted heparin were analyzed to verify their bioavailability. The average amount of heparin extracted per kilogram of pig by-products was 439 mg from the liver, 127 mg from the lung, 398 mg from the heart, 261 mg from the stomach, 197 mg from the small intestine, and 239 mg from the large intestine. Various enzymes were used to extract heparin, and the amount of extracted heparin was similar. Based on 1 g of pig by-product, the enzymes trypsin, papain, and alkaline-AK could extract 1,718 mg, 1,697 mg, and 1,905 mg of heparin, respectively. Heparin extracted from pig by-products showed antihypertensive activity and antimicrobial activity against Staphylococcus aureus at low populations. These results indicated that heparin can be obtained from pig by-products at a low cost.

• Food Science of Animal Resources
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• v.43 no.1
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• pp.184-194
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• 2023

Recently, interest in food-derived bioactive peptides as promising ingredients for the prevention and improvement of hypertension is increasing. The purpose of this study was to determine the structure and antihypertensive effect of an antioxidant peptide purified from velvet antler in a previous study and evaluate its potential as a various bioactive peptide. Molecular weight (MW) and amino acid sequences of the purified peptide were determined by quadrupole time-of-flight electrospray ionization mass spectroscopy. The angiotensin I-converting enzyme (ACE) inhibition activity of the purified peptide was assessed by enzyme reaction methods and in silico molecular docking analysis to determine the interaction between the purified peptide and ACE. Also, antihypertensive effect of the purified peptide in spontaneously hypertensive rats (SHRs) was investigated. The purified antioxidant peptide was identified to be a pentapeptide Asp-Asn-Arg-Tyr-Tyr with a MW of 730.31 Da. This pentapeptide showed potent inhibition activity against ACE (IC₅₀ value, 3.72 μM). Molecular docking studies revealed a good and stable binding affinity between purified peptide and ACE and indicated that the purified peptide could interact with HOH2570, ARG522, ARG124, GLU143, HIS387, TRP357, and GLU403 residues of ACE. Furthermore, oral administration of the pentapeptide significantly reduced blood pressure in SHRs. The pentapeptide derived from enzymatic hydrolysate of velvet antler is an excellent ACE inhibitor. It might be effectively applied as an animal-based functional food ingredient.

• Transactions of the Korean hydrogen and new energy society
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• v.19 no.2
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• pp.124-131
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• 2008

Crude cytoplasmic fraction of phototrophic purple sulfur bacterium, Thiocapsa roseopersicina NCIB 8347, were initially prepared and purified by sonication, ultracentrifugation, ammonium sulfate fractionation and heat-treatment and it has been previously reported. Using various applications of chromatography far the purification of membrane-bound and soluble hydrogenases from heat-treated enzyme fraction were studied at present report. When the heat-treated enzyme preparation was applied to the anion column chromatography using Q-sepharose, Fraction I and II, which were extracted with the KCl 0-0.5 M gradient, showed the specific evolution hydrogenase activity 3.86 and 2.27 U/mg-protein respectively. Specific hydrogenase activitys of Fraction I and II were further increased to 4.35 and 7.46 U/mg-protein for Fraction I and to 2.49 and 4.41 U/mg-protein fur Fraction II respectively, when hydrophobic interaction column, Phenyl superose, and anion exchange column, Mono-Q, were applied. Size exclusion chromatography using superdex 200 concentrated the hydrogenase Fraction I and II to 9.19 and 7.84 U/mg-protein respectively at the final step of purification.