• Korean Journal of Food Science and Technology
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• v.32 no.1
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• pp.37-41
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• 2000

This study has been carried out to investigate the chemical composition of Acorus calamus L., a wild plant (Chang Po) which has long been used as a medicine or a hair rinse in Korea and China. Potassium was found to be the most predominant mineral in leaf and root, followed by calcium, magnesium, and phosphorus, in a decreasing order. Contents of potassium in leaf and root account for 54a.65 mg% and 242.87 mg%, respectively. Contents of these minerals in leaf were higher value than that in root. Glucose and fructose were found to be the major free sugars in leaf and root. Malic acid was the most abundant organic acid of leaf and root, and followed by citric acid. Fourteen different kinds of fatty acids were identified from the leaf and root. Content of unsaturated fatty acids. such as linolenic, and linoleic acid ware higher than that of saturated fatty acids. Content of total amino acids was 3 times higher in leaf than that in root. Leucine was the major amino acid in leaf and glutamic acid in root.

• Korean Journal of Food Science and Technology
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• v.31 no.6
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• pp.1589-1595
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• 1999

Reverse osmosis(RO) and rotary evaporation, freezer drying and spray drying as concentration and dehydration methods were, respectively, employed to investigate their effect on the flavor quality of ginger powder. Rotary evaporation and spray drying methods were more effective to restrict the browning of ginger powder than RO and freezer drying methods. Concentration methods had no effect on the free amino acids and free sugar contents of ginger powder, but freezer drying resulted in the less quality loss than spray drying. And the powder prepared from enzymatically hydrolyzed extract contained less crude protein, crude ash, browning and the changes in free amino acids, but had more the crude fat, solubility and free sugars than that from ginger extract obtained by filter press. Sensory results indicated that quality of ginger powder prepared by RO concentration and freeze drying of enzymatically hydrolyzed extract was as good as that without enzyme hydrolysis

• Journal of Microbiology and Biotechnology
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• v.22 no.12
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• pp.1705-1713
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• 2012

A gene encoding ${\beta}$-glucosidase was cloned from Weissella cibaria 37, an isolate from human feces. Sequence analysis showed that the gene could encode a protein of 415 amino acids in length, and the translated amino acid sequence showed homology (34-31%) with glycosyl hydrolase family 1 ${\beta}$-glucosidases. The gene was overexpressed in E. coli BL21(DE3) using pET26b(+) and a 50 kDa protein was overproduced, which matched well with the calculated size of the enzyme, 49,950.87 Da. Recombinant ${\beta}$-glucosidase was purified by using a his-tag affinity column. The purified ${\beta}$-glucosidase had an optimum pH and a temperature of 5.5 and $45^{\circ}C$, respectively. Among the metal ions (5mM concentration), $Ca^{2+}$ slightly increased the activity (108.2%) whereas $Cu^{2+}$ (46.1%) and $Zn^{2+}$ (56.7%) reduced the activity. Among the enzyme inhibitors (1 mM concentration), SDS was the strongest inhibitor (16.9%), followed by pepstatin A (45.2%). The $K_m$ and $V_{max}$ values of purified enzyme were 4.04 mM and 0.92 ${\mu}mol/min$, respectively, when assayed using pNPG (p-nitrophenyl-${\beta}$-D-glucopyranoside) as the substrate. The enzyme liberated reducing sugars from carboxymethyl cellulose (CMC).

• Applied Biological Chemistry
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• v.31 no.2
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• pp.147-153
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• 1988

An assessment of the nutritional aspects on irradiated garlic bulbs, stored for 10 months at low$(3{\pm}1^{\circ}C,\;75{\sim}85%\;R.H.)$ and room$(12{\pm}5^{\circ}C,\;75{\sim}85%\;R.H.)$, was performed by means of investigations on the changes in some chemical composition. Ionizing energy treatment at 0.1kGy gamma-ray brought about no significant changes in the moisture content of stored garlic, but it contributed to the reduction of the changes in total available carbohydrate content of stored garlic. After 8 months of storage, the content of free sugars was significantly higher in nonirradiated garlic than in irradiated garlic, especially in low temperature storage. The 0.1kGy irradiation at the sprout-inhibition dose had no apparent effect on the content of ascorbic acid in stored garlic, and sulfurcontaining amino acids appeared to be little affected by the irradiation at 0.1kGy, even though there were some sensitive amino acids like glutamic and aspartic acids.

• Plant Biotechnology Reports
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• v.3 no.3
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• pp.225-241
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• 2009

We investigated the transcriptional profiles of Japanese indigenous grape cultivar 'Koshu' (Vitis vinifera) leaf and berry skin during ripening. In leaf, 64 genes were abundantly transcribed at the end of $v{\acute{e}}raison$ (14 weeks post-flowering), whereas the expression of 61 genes was upregulated at the end of ripening (20 weeks post-flowering). In berry skin, 67 genes were abundantly transcribed at the end of $v{\acute{e}}raison$, whereas the expression of 86 genes was upregulated at the end of ripening. Gene expression associated with biological processes was activated in both tissues at the end of ripening. The expression of genes associated with photosynthesis, sugar synthesis, anthocyanin synthesis, cinnamic acid synthesis, and amino acid metabolism was observed in leaf and berry skin during ripening, together with the accumulation of sugars, anthocyanins, cinnamic acids, and amino acids. Transcripts of AUX/IAA family proteins that repress the activities of auxin-induced proteins were expressed in berry skin at the end of $v{\acute{e}}raison$. Transcripts of genes related to the ubiquitin-proteasome system that degrades AUX/IAA family proteins were abundantly expressed in berry skin at the end of ripening, suggesting that the expansion of skin cells at $v{\acute{e}}raison$ is suppressed by AUX/IAA family proteins, and that the ubiquitin-proteasome system induces the expansion of skin cells during ripening by degrading AUX/IAA family proteins. These transcriptional profiles, which provide new information on the characteristics of 'Koshu' grapevine during ripening, may explain the unique characteristics of 'Koshu' grape in comparison with those of European grapes used for winemaking, and may contribute to the improvement of 'Koshu' grape quality.

• Food Science and Preservation
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• v.6 no.4
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• pp.481-487
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• 1999

This study was determined to change in chemical composition of Mume(Prunus mume Sieb. et Zucc) fruits during maturation. There were no differences in the soluble solid and moisture content among varieties, but the soluble solid slowly increased with maturing. The pH and ash content were slightly decreased with maturation. The green color of 'Nanko' fruits was maintained for 92days after full bloom at the greeness value of -3.81 Whereas, the chlorophyll content of 'Koume' fruits remarkably decreased and it was not suitable for the processing of immature green Mume fruits. The titratable acidity increased during maturation. The organic acids were mainly composed of malic acid and citric acid. The malic acid was significantly decreased during maturation, whereas citric acid increased. Major free sugars and sugar alcohols were sucrose, glucose, fructose, sorbitol and maltose. Sucrose content increased as the maturity proceeded, whereas glucose and sorbitol were decreased. The total contesnt of free amino acids decreased with maturation and the total free amino acids in the flesh of fruits were occupied by asparagine at the range of 60 to 78%.

• The Korean Journal of Food And Nutrition
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• v.34 no.3
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• pp.255-262
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• 2021

Centella asiatica (CA) is a vegetable that has been used for medicinal purposes for a long time, but it is not well known in Korea. In this study, the approximate analysis, physicochemical properties, free sugars, free amino acids and minerals of native and improved CA cultivated in Chungju area were measured. And the antioxidant contents and activities of CA solvent extracts were measured. There was no significant difference between native and improved species. As for the characteristics of CA, it was confirmed that the improved species had a large weight, size and a tough texture. Glucose was detected in native CA, fructose, glucose and sucrose were detected in improved species. A total of 15 free amino acids were detected and the content was slightly higher in improved species than in native species. The mineral content in CA was slightly higher in the improved species, and the detected minerals were Na, P, Ca, K, Mg and Fe. Polyphenols, ascorbic acid and flavonoids in each extraction solvent (water, 70% and 100% ethanol) were all higher in the improved species than in native species. And it was found that the antioxidant activities of ethanol extracts were higher than that of water.

• Microbiology and Biotechnology Letters
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• v.51 no.2
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• pp.147-156
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• 2023

Tetragenococcus halophilus CY54, an isolate from jeotgal, grows best in media with 5% NaCl and can grow at 18% and higher salt concentration. Three different doenjang samples were prepared with multiple starters including T. halophilus CY54. TBZA doenjang was prepared with T. halophilus, Bacillus subtilis, Zygosaccharomyces rouxii and Aspergillus oryzae. BZA doenjang was prepared with the same 3 starters except T. halophilus. KACC doenjang was prepared with a single starter, B. subtilis KACC16750. During 16 weeks of fermentation at 25℃, the viable counts were maintained in the range of 7-8 log CFU/g in all 3 samples. As fermentation progressed, pH decreased and titratable acidity (TA) gradually increased. Crude protein contents decreased slightly. TBZA doenjang showed higher amino-type nitrogen (ANN) and volatile basic nitrogen (VBN) contents, and KACC doenjang showed higher ammonia-type nitrogen (AMN) content. TBZA doenjang showed higher fibrinolytic and protease activity than other doenjang samples. Metabolites analyses by GC/MS showed that doenjang samples were separated from each other by partial least squares-discriminant analysis (PLS-DA) analysis. Seventeen major metabolites involved in the differences between samples were identified and they included organic acids, amino acids, sugars, fatty acids and alcohols. TBZA doenjang showed higher contents for most metabolites responsible for flavor and taste of fermented foods including doenjang. These results showed that T. halophilus could be useful as a starter for doenjang and can improve the product quality by accelerating the fermentation processes.

• Journal of the Korean Society of Food Culture
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• v.21 no.4
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• pp.426-432
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• 2006

This study was conducted to investigate the changes in quality characteristics of frozen maesil according to thawing methods. The quality of maesil thawed in microwave oven was superior to those thaw in refrigerating temperature(5 $^{\circ}$) and in room temperature(25 $^{\circ}$). Drip loss of maesil thawed in microwave oven was 3.2${\pm}$0.2%. The total content of free sugars of maesil was 426.6 mg%, and 3% of them was decreased during thawing in microwave oven. The total content of organic acids was 5,297.2 mg%, and 2.5% of them was decreased during thawing in microwave oven. The total content of free amino acids was 281.4 mg%, and 2.1% of them was decreased during thawing in microwave oven. The principle ingredients of frozen maesil was stand for the lost contents of free sugar and a content loss of free organic acid and free amino acid were the fewest by thawing. Antioxidant effect for soybean oil and linoleic acid of maesil extract were expressd POV and TBA values. Antioxidative activity of fresh maesil extract was highest followed by maesil thawed in microwave oven, thawed in refreezing temperature (5$^{\circ}$)and room temperature (25$^{\circ}$)

• Food Science and Preservation
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• v.11 no.3
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• pp.293-298
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• 2004

This study was carried out to investigate the changes on the components of salted eggplant(shikibu) during storage. The contents of total and reducing sugars were decreased during storage, and the tendency of decrease was lower in the salted eggplants of vacuum packing storage than in the salted eggplants of rice bran immersion storage. The contents of acetic and malic acid were higher than other organic acids. The content of acetic acid was increased during storage, but malic acid was decrease. The major amino acid were valine, leucine, aspartic acid, glutamic acid. The content of essential amino acids was increased during storage. Aspartic acid, alanine, cystine and proline were high content of free amino acids. The contents of phosphoserine, taurine, Y-aminoisobutyric acid and hydroxyproline were higher than others. Posphoserine content was decreased during storage, but Y-aminoisobutyric acid was increased to 5 times of fresh eggplant at 20 days of storage.