• Food Science of Animal Resources
• /
• v.28 no.1
• /
• pp.91-98
• /
• 2008

This study was conducted to reveal the effects of pork consumption on the renal and hematochemical indices of workers occupationally exposed to an unclean environment for 6 weeks. Forty-five free-living volunteers were recruited from the workers employed in a car-engine part factory and a leather dyeing company in the Gyeonggi area. Volunteers were to submit a subject consent form prior to the study. They were asked to complete a questionnaire on dietary habits, and blood and urine samples were collected before and after the pork consumption trial. Pork dishes were fed twice weekly (150g per meal) as part of lunch or dinner at the work place. Urine N-Acetyl-${\beta}$-D-glucosamidase (NAG) levels were reduced after the trial, but total-cholesterol, HDL-and LDL-cholesterol levels did not change. However, triglyceride levels did increase significantly (p<0.005). The Zn, Pb, and Cd concentrations in serum tended to decrease, though without statistical significance. In conclusion, the regular consumption of pork may be beneficial for renal functions, however further research in this area is needed.

• Journal of Life Science
• /
• v.27 no.11
• /
• pp.1324-1330
• /
• 2017

Salt, or sodium chloride (NaCl), is a critical ingredient in many foods. It has roles in the flavor profiles of food products, textures of foods and preservation of foods against microbes. However, it increases risks of hypertension and is closely related to the development of cardiovascular disease. In recent years, health concerns related to sodium intake caused an increased demand for salt-reduced products in worldwide; it became necessary to develop natural salt-alternative products that are globally competitive. In a recent study, researchers succeeded in obtaining a natural salt enhancer through the hydrolysis of vegetable- and animal-matter mixtures. This study used various methods to identify and quantify peptide-containing arginine as a salt-alternative peptide (SAP) in an optimum combination. Arginine, or dipeptide-containing arginine, was analyzed as a standard substance using an NMR spectroscopy. The NMR carbon signal of the guanidine group of the standard substance was verified in a similar location (the L-arginine (Arg) was 156.8 ppm, the Arg-Alanine was 156.4 ppm and the Arg-Serine was 156.4 ppm). The results suggested that it is possible to analyze peptide-containing arginine quantitatively through the hydrolysis of vegetable- and animal-matter mixtures.

• Korean Journal of Food Science and Technology
• /
• v.29 no.4
• /
• pp.657-662
• /
• 1997

An attempt was made to investigate the chemical compositions of green pumpkin, edible flesh and seed of ripened pumpkin (Cucurbita moschata Duch.). The proximate compositions were moisture 9.34%, 11.98%, protein 12.70%, 13.38%, lipid 11.31%, 0.85%, carbohydrate 64.32%, 62.18%, fiber 6.31%, 4.54% and ash 6.05%, 7.76% in green and ripened pumpkin, respectively. The compositions of free sugar were glucose, fructose, sucrose, lactose and maltose in green and ripened pumpkin, respectively. During flesh growth, glucose, maltose and lactose was increased but sucrose and fructose was decreased in pumpkin. Pattern of 15 amino acid compositions in green and ripened pumpkin was shown to be of similarity. Major amino acids were glutamic acid, aspartic acid and alanine in green pumpkin and edible flesh of ripened pumpkin. And major amino acid in seed of ripened pumpkin were glutamic acid, arginine, aspartic acid and leucine. The predominant fatty acids were palmitic acid, linolenic acid, linoleic acid and oleic acid in green and ripened pumpkin, respectively. And those in seed of ripened pumpkin were linoleic acid, palmitic acid and oleic acid. The richest mineral contained in the green and ripened pumpkin was shown to be K and followed by Ca, Mg, Na and Fe in order.

• Korean Journal of Food Science and Technology
• /
• v.26 no.4
• /
• pp.393-397
• /
• 1994

The study was carried out to develop the powdered smoked-dried anchovy products as a natural flavoring substance. The processing conditions, chemical and taste compounds of products were as follows: The raw anchovy were washed, and then boiled 5 minutes in $5{\sim}6%$ NaCl and 1.0% sodium erythorbate solution. Boiled anchovy were smoked in smoking house at $40^{\circ}C$ for 4 hours as the first stage, and then increased temperature up to $80^{\circ}C$ as the second stage, and finally smoked 8 hrs at $80^{\circ}C$ to maintain the moisture content between 9 and 10 percent. The smoked-dried anchovy were pulverized and screened to be 50 mesh of particle size, and finally packed in PET/Al/CPP film bag. The moisture, crude lipid content and salinity of powdered smoke-dried anchovy were 9.4%, 9.6% and 6.9%, respectively. Fatty acid composition of product was mainly consisted of polyenes (43.4%) such as 22 : 6 and 20 : 5, followed by saturates (36.9%), monoenes (19.7%). The principal taste compounds of product were IMP, 466.5 mg/100g; free amino acids such as His, Tau, Pro, Lys, Ala and Glu, 1179.2 mg/100g; non-volatile organic acids such as lactic acid and succinic acid, 617.9 mg/100g; total creatinine, 595.9 mg/100g; small amount of betaine and TMAO. To make a instant soup, it was desirable for taste of products that powdered smoked-dried anchovy were mixed with 20% salt, 4.0% sugar, 3.0% MSG, 1.0% onion powder, 1.0% garlic powder and 1.0% black pepper.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.27 no.5
• /
• pp.509-514
• /
• 1994

A processing method for fermented paste of favorable flavor and texture using pen shell by-product was investigated. The pen shell by-product was homogenized with the addition of water and hydrolyzed with $5\%$ of Protin P(105 PU/g) at $55^{\circ}C$ for 1 hour. Flavor of the hydrolysate could be improved by thermal treatment at $100^{\circ}C$ for 40 minutes with $10\%$ of invert sugar. $2\%$ of agar-agar and $6\%$ of starch added to hydrolysate emulsified by $8\%$ of polyglycerol condensed ricinoleate(PGDR) were significantly effective for the improvement of rheological properties such as hardness, springiness and chewiness of the fermented paste. $15\%$ of table salt was finally added to the product of fermented pen shell paste. The contents of moisture, protein, lipid, carbohydrate and salinity of the product were $62.7\%,\;3.2\%,\;4.4\%,\;10.6\%\;and\;15.6\%$, respectively. The major free amino acids were glutamic acid, arginine, aspartic acid, leucine, lysine, glycine and alanine. The product was stable for the storage of 60 days at $23{\pm}3^{\circ}C$ on bacterial growth.

• Korean Journal of Food Science and Technology
• /
• v.29 no.3
• /
• pp.400-406
• /
• 1997

Chemical composition and antimicrobial activity of Houttuynia cordata Thunb. were investigated to develop a natural food preservative from it. Aspartic acid, glutamic acid, glycine and arginine were major amino acids of Houttuynia cordata Thunb., but were present in a trace amount. Free sugars were composed of glucose, fructose, sucrose and maltose and major fatty acids were linolenic acid, linoleic acid, oleic acid, and palmitic acid. Mineral elements were potassium, calcium, magnesium, iron, zinc, and copper. Antimicrobial activities were shown in acidic, neutral and phenolic fraction of Houttuynia cordata Thunb., but not in basic fraction. Among the four fractions, neutral fraction showed the strongest antimicrobial activities against microorganisms tested, such as Pseudomnas aeruginosa, Micrococcus luteus, Bacillus subtilis, Aspergillus parasiticus and Aspergillus flavus. Minimum inhibitory concentration (MIC) and minimum lethal concentration (MLC) of the neutral fraction varied according to microoganisms tested. The lowest values of MIC (0.0075 g eq./mL) and MLC (0.10 g eq./mL) were obtained from Pseudomonas aeruginosa.

• Journal of the Korean Chemical Society
• /
• v.5 no.1
• /
• pp.33-37
• /
• 1961

We have shown that carboxy-peptidase destroys the biological activity of angiotensin octa-and deca-peptides. Since Proline occurs as the seventh amino acid from the amino end of the chain and since carboxypeptidase does not cleave proline from a peptid chain, it is evident that the heptapeptid H.asp-arg-val-tyr-ileu-his-pro.OH is formed by this hydrolysis. This peptide must then be biologically inactive. In order to determine whether the phenyl group of the C-terminal amino acid was the necessary requirement for biological activity of the octapeptide, $ala^8$ angiotensin octapeptide(amino acids of peptides numbered from amino end) was synthesized. For this synthesis the four dipeptides were prepared: carbobenzoxy-L-prolyl-L-alanine-P-nitrobenzyl-ester, m.p. $134-135^{\circ}C,$ carbobenzoxy-L-isoleucyl-imidazole benzyl-L-histidine methyl ester, m.p. $114-116^{\circ}C,$ carbobenzoxy-L-valyl-L-tyrosine hydrazide and carbobenzoxy B-benzyl-L-aspartyl-nitro-L-arginine. The first three dipeptides were obtained as crystalline compounds. Imidazole-benzyl-L-histidine was used in the hope that it would block the histidine imidazole against side reactions in steps subsequent to the formation of the C-terminal tetrapeptide. Also, it was through that the imidazole benzylated peptides would be easier to crystallize. This, however, was not the case. The tetrapeptide, carbobenzoxy-L-isoleucyl-L-im, benzyl-histidyl, L-prolyl-L-alanine-nitrobenzyl ester was not obtained in a crystalline form. Neither could the mono-or dihydrobromide of the tetrapeptide free base be induced to crystallize. Carbobenzoxy-L-valyl-L-tyrosine azide was condensed with the tetrapeptide free base to yield the protected hexapeptide; carbobenzoxy-L-valyl-L-tyrosyl-L-isoleucyl-L-im, benzyl, histidyl-L-Prolyl-L-alanine-nitrobenzyl ester. Upon removal of the carbobenzoxy group with hydrogen bromide in acetic acid an amorphous free base hexapeptide ester was obtained. This compound gave the correct C, H, N analysis and contained the six amino acids in the correct ratio. The octapeptide was obtained by condensing this hexapeptide with carbobenzoxy-B-benzyl-L-aspartyl-nitro, L-arginine using the mixed anhydride method of condensation. This amorphous product was proven to be homogenous by chromatography in two solvent systems and upon hydrolysis yielded the eight amino acids in correct ratio. The five protecting groups were removed from the octapeptide by hydrogenolysis over palladium black catalyst. Biological assay of the free peptide indicated that it possessed less than 0.1 per cent of both pressor and oxytocic activity of the phenylalanine8 angiotensin. This suggests that the phenyl group is a point of attachment between angiotensin and its biological receptor site.

• Journal of Life Science
• /
• v.16 no.7 s.80
• /
• pp.1148-1157
• /
• 2006

A hyperthermophilic bacterium Thernotoga maritima produced thermostable ${\beta}-glucosidase$. The gene encoding ${\beta}-glucosidase$ from T. maritima MSB8 was cloned and expressed in Escherichia coli. The en-zyme (BgIB) hydrolyzed ${\beta}-glucosidase$ linkages between glucose and alkyl, aryl of saccharide groups such as salicin, arbutin, and $_pNPG$. The insert DNA contained ORF with 2,166 bp encodes a 721 amino acids (calculated molecular mass of 80,964 and pl of 4.93). The amino a.id sequence of BglB showed the similarity to family 3 glycosyl hydrolases. The molecular weight of the enzyme was estimated to be approximately 81kDa by MUG-nondenaturing PAGE (4-methylumbelliferyl 13-D-glucoside-nondenaturing polyacrylamide gel electophoresis) and SDS-PACE. The ${\beta}-glucosidase$ exhibited maximal activity at pH 7.0 and $80^{\circ}C$. By exchanging two possible residues (Glu-232 and Asp-242) to Ala by site-directed mutagenesis method, it was found that these were essential for enzymatic activity.

• Journal of Biosystems Engineering
• /
• v.29 no.1
• /
• pp.37-44
• /
• 2004

This study was conducted to develop a new drying method far reducing the drying cost and time and to investigate the drying characteristics of oak mushroom. A far infrared dryer of down draft air flow type used for this experiment can control the drying parameters, such as far infrared heater temperature and aeration velocity. The far infrared drying tests were performed at aeration velocities of 0.3 and 0.6m/s under the temperature of 90 and 100$^{\circ}C$ in for infrared heater, respectively. The results were compared and analyzed with those of an heated air drying method used as a control in terms of properties representing the drying characteristics. such as shrinkage rate, color, energy consumption amino acid components, drying rate and moisture ratio. The results obtained from this research can be summarized as follows. 1. The drying rate of far infrared drying was faster than that of heated air drying. With high temperature of far infrared heater and slow aeration velocity, the far infrared drying of down draft air flow type was superior to the heated air drying. 2. Most of far infrared drying conditions required less energy consumption than heated air drying. 3. The shrinkage rates of heated air drying and far infrared drying were decreased by 17.0% and 18.2∼19.8%, respectively. 4. The difference of color on oak mushroom surface before and after drying can be represented as $\Delta$E. $\Delta$E values of far infrared drying and heated air drying were 2.39∼4.55 and 6.77, respectively. 5. The amounts of free amino acids were higher in the far infrared than in the heated air drying. In addition the amounts of Gln and Glu generally were increased and those of Ala, Leu, and Val were decreased in order.

• Journal of the Korean Magnetic Resonance Society
• /
• v.12 no.1
• /
• pp.14-25
• /
• 2008

To investigate the 3-bond connectivity of human brain metabolites by scalar coupling interaction through 2D-correlation spectroscopy (COSY) techniques using high field NMR spectroscopy. All NMR experiments were performed at 298K on Unity Inova 500 or 600 (Varian Inc.) equipped with a triple resonance probe head with z-shield gradient. Human brain metabolites were prepared with 10% $D_2O$. Two dimensional 2D COSY spectra were acquired with 4096 complex data points in $t_2$ and 128 or 256 increments in $t_1$ dimension. The spectral width was 9615.4 Hz and solvent suppression was achieved using presaturation using low power irradiation of the water resonance during 2s of relaxation delay. NMR data were processed using VNMRJ (Varian Instrument) software and all the chemical shifts were referenced to the methyl resonance of N-acetyl aspartate (NAA) peak at 2.0 ppm. Total 10 metabolites such as N-acetyl aspartate (NAA), creatine (Cr), choline (Cho), glutamine (Gln), glutamate (Glu), myo-inositol (Ins), lactate (Lac), taurine (Tau), ${\gamma}$-aminobutyricacid (GABA), alanine (Ala) were included for major target metabolites. Symmetrical 2D-COSY spectra were successfully acquired. Total 14 COSY cross peaks were observed even though there were parallel/orthogonal noisy peaks induced by water suppression. Except for Cr, all of human brain metabolites produced COSY cross peaks. The spectra of NAA methyl proton at 2.02 ppm and Glu methylene proton ($CH_2(3)$) at 2.11 ppm and Gln methylene proton ($CH_2(3)$) at 2.14 ppm were overlapped in the similar resonance frequency between 2.00 ppm and 2.15 ppm. The present study demonstrated that in vitro 2D-COSY represented the 3-bond connectivity of human brain metabolites by scalar coupling interaction. This study could aid in better understanding the interactions between human brain metabolites in vivo 2D-COSY study. Also it would be helpful to determine the molecular stereochemistry in vivo by using two-dimensional MR spectroscopy.