• Microbiology and Biotechnology Letters
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• v.19 no.1
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• pp.14-20
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• 1991

- The purpose of this work is to investigate the effects of various substrates on biosynthesis of ethylene by the Kudzu strain of Pseudomonas syn'ngae pv. Phaseolicola causing halo blight. In the intact cell of P. sym'ngue, optimal condition for ethylene production was achieved at p1-I 7.5 and $30^{\circ}C$ for 9 to 10 hours of culture. Ethylene was most effectively produced from amino acids such as Asn, Gln, Asp ans Glu, compared to those of various kinds of sugars. While ethylene production from $\alpha$-ketoglutarate ($\alpha$-KG) was gradually increased throughout 51 hours incubation period tested. Ethylene production derived from citrate, $\alpha$-KG and oxalacetate as well as a few amino acids was further enhanced by the addition of histidine or arginine. In cell-free ethylene-forming system, ethylene was most effectively produced from $\alpha$-KG, compared to those from citrate, oxalacetate, Glu, Arg, or Asp, at 0.5 mM among the range from 0.25 mM to 5 mM. Anlinooxyacetate, an inhibitor of a pyridoxal phosphate-linked enzyme, completely inhibited ethylene evolution derived from Glu but not affect that derived from $\alpha$-KG. The results obtained in this work suggest that $\alpha$-KG might be a direct precursor of ethylene production in this organism than any other substrates tested.

• Food Science and Preservation
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• v.7 no.2
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• pp.189-194
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• 2000

To study the potential of the Zanthoxylum schinifolium and Z. piperitum leaves, as raw materials for functional food and medicine, apart from male and female, chemical components were carried out. Among general components of sancho and chopi leaves, moisture and crude protein were higher sancho leaf than chopi leaf, but total sugar and crude fat were higher chopi leaf than sancho leaf and the components of major minerals were K, Ca, Mg and Na. Among free sugars, glucose(0.24% and 0.21%) and sucrose(0.19% and 0.27%) were the highest contents in sancho and chopi leaves(male and female), respectively. The organic acid were isolation and identification as malic acid and citric acid, citric acid is higher than malic acid. The total amino acid of sancho and chopi leaves contained proline and glutamic acid in male and female sancho and female chopi leaves, glutamic acid and aspartic acid in male chopi leaf highly in order. The fatty acid contents of four samples were high 15.16%, 9.76%, 8.78% and 9.29% of linolenic acid, respectively. Among many volatile compounds, limonene(13.25% and 19.16%) and citronellal(34.37% and 29.66%) were predominant flavor compounds in sancho and chopi leaves(male and female), respectively.

• Food Science and Preservation
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• v.5 no.1
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• pp.57-63
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• 1998

To furnish basic data about the utilization of Korean loquat as flood, this experiment was conducted. Nutritional components in leaves, fruit excluded seed, flesh and seed of Korean loquat were analyzed as follows : moisture 48.7%, 87.8%, 88.3% and 59.5% ; total sugar 1.57%, 7.21%, 7.36% and 2.41% ; crude protein 5.23%, 1.61%, 1.44% and 4.31% in each portion, respectively. The highest mineral contents of loquat leaves, fruit excluded seed, flesh and seed were Ca 2,458ppm, K 661ppm, 654ppm and 1,528ppm, and water soluble vitamins such as ascorbic acid, thiamin and pyridoxine were confirmed in different pares of Korean loquat, the contents of those were high thiamin 5.86mg% in leaves and ascorbic acid 1.l0mg%, 1.26mg% and 4.90mg% in fruit excluded seed flesh and seed, respectively. The contents of free sugars were high sucrose 0.87%, glucose 0.62%, 0.6475 and rhamnose 0.20%, and major organic acid were detected oxalic acid 1,693.70mg%, malic acid 201.70mg%, 207.60mg% and citric acid 55.70mg% in each portion, respectively. Free amino acid were identified 21, 14, 14 and 16 kinds of leaves, fruit excluded seed, flesh and seed, respectively and their contents in each portion were highest glutamic acid 280.22mg%, proline 35.l0mg%, glutamic acid 56.96mg% and sarcosine 230.24mg%, respectively. Volatile components were identified 25 and 11 kinds of leaves and flesh and their contents were highest d-nerolidol 28.70ppm, hexadecanoic acid 16.67ppm, respectively.

• Food Science and Preservation
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• v.14 no.1
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• pp.61-66
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• 2007

This study investigated changes in physicochemical properties of onion powders during various drying conditions. The moisture content during vacuum drying at $40^{\circ}C$ remained at 5.23% for 5 days of drying, and it was possible to quickly obtain day powder Weight reduction upon $-70^{\circ}C$ vacuum drying was 90% after 7 days. The large change in browning caused by vacuum freeze drying was lowest ($OD_{420}\;of\;1.173$) after 7 days of drying. The content of vitamin C increased with vacuum freeze drying. The major free sugars were fructose, glucose and sucrose. Of organic acids, citric acid was prominent and, after vacuum freeze drying, showed a high value of 1,965 mg/100g. Free amino acids noted were L-arginine, ${\beta}-alanine$, L-alanine and L-threonine. In summary, vacuum freeze drying at $-70^{\circ}C$ is optimal.

• Journal of Korean Society of Forest Science
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• v.88 no.4
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• pp.562-567
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• 1999

Dendropanax morbifera Lev. leaves were collected during different seasons to analyze the chemical components. In proximate composition the leaves collected in spring had the highest moisture content and in winter had the lowest. Lipid, ash and fiber contents gradually increased from spring to winter and in winter had the highest. Protein content decreased until summer and then it increased. All of free sugars detected have gradually increased during the growing season. Unsaturated fatty acids content was higher than that of the saturated fatty acids and the major saturated and unsaturated fatty acids were arachidic acid and cis-13,16-docosadienoic acid. respectively. Fifteen free amino acids detected with arginine content being the highest regardless of season and amino acid content gradually decreased during the seasons. The highest content of mineral elements was potassium in leaves collected in spring, with calcium was the highest in leaves picked in other seasons. Vitamin C content was gradually decreased over the growing season and soluble tannin content increased notably.

• Journal of the Korean Society of Food Science and Nutrition
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• v.15 no.4
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• pp.1-9
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• 1986

The mashes of soybean paste were preparea using the conventional meju fermented naturally by wild microoganisms or the new types of meju fermented by pure cultures of Aspergillus oryzae, Bacillus natto and B. subtilis to elucidate changes during the aging period. The results obtained are as follows ; The soybean paste made with conventional meiu and Asp. oryzae meju showed higher content of amino nitrogen than those of B, natto and B. subtilis meju. Soybean paste made with conventional meju contained a little more content of total and reducing sugars than other soybean pastes. ph during aging period was higher than 5.0 for the Asp. oryzae paste while less than 4.5 for B. subtilis paste. Aspartic acid. threonine, serine, glutamic acid, glycine, alanine, cystine, valine, methionne, leucine and histidine for Asp. oryzae paste ; tyrosine, arginine and proline for conventional meju paste; and isoleucine and phenylalanine for B. subtilis paste were found to be peak amount 90 days after the preparation. The content of total free amino acid was high in the order of Asp. oryzae paste, conventional paste, B. natto paste and B. subtilis paste.

• The Korean Journal of Food And Nutrition
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• v.29 no.5
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• pp.706-715
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• 2016

Nutritional composition and physicochemical properties changes in mustard leaf kimchi were investigated during fermentation of up to 3 months. The pH decreased, and the titratable acidity gradually increased according to increase of fermentation periods. Fructose and glucose were the major free sugars in mustard leaf kimchi, and their amounts were significantly decreased with fermentation periods (p<0.05). Lactic acid content showed a significant increase with maximum increase at 3 months. All types of kimchi contained 20 amino acids, but the content of most amino acid fluctuated during fermentation. Except for K and Zn, the content of other ingredients including Ca, Fe, Mg, Na, Se were the highest in kimchi fermented for 2 months. The unsaturated fatty acid of mustard leaf kimchi was higher than that of saturated fatty acid, and total fatty acid of kimchi significantly decreased after 2 months (p<0.05). Most vitamin contents showed a tendency to decrease with fermentation, in particular, vitamin B complex except for $B_2$ significantly decreased after 3 months (p<0.05). The results provide fundamental data for determining the appropriate fermentation period to improve the quality of kimchi.

• Korean journal of food and cookery science
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• v.29 no.5
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• pp.525-531
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• 2013

Nutritional components and quality characteristics of drained soybean boiling water(DBW), which is discarded in the mass production of fermented soy foods, were compared with raw soybean(Control) and Cheonggukjang(CGJ) to provide the basic data for its recycle. The contents of moisture, crude protein, crude lipid and crude ash of DBW were shown as 87%, 2.2%, 0.15% and 1.42%, respectively. Decreased total amino acid of 1,677.8 mg/100g in DBW was comparable with 29,051.1 mg/100g in control, however, there was no great difference in the proportion of essential amino acid to the total. While the total sugar contents were decreased in both DBW and CGJ with 8.39% and 7.17% each from the control of 11.50%, the reducing sugars were increased with higher amount of 6.44% in CGJ and 8.30% in DBW than 5.60% in control. pH of DBW was lower than both of the control and CGJ. Hunter's color values revealed the increase of redness(a value) and yellowness(b value) of DBW and CGJ suggesting that Maillard reaction products were produced by the heating and fermentation process. Polyphenol compounds were highly abundant in CGJ of 0.74 tannic acid equivalent(mg/g) followed by similar low amounts of 0.33 and 0.29 tannic acid equivalent(mg/g) in DBW and control, respectively. Antioxidative activity determined by Electron Donating Ability(%) using DPPH radical showed that CGJ, of which polyphenols were the highest, has the strongest electron donating ability with the lowest $EC_{50}$ value of 5.91 mg/mL. DBW was much lower but similar with the control. From the above results the drained soybean boiling water was shown to have many nutritional and functional components as much as soybean, therefore, it could be a potent reusable food material.

• Applied Biological Chemistry
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• v.31 no.3
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• pp.261-266
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• 1988

For the effective utilization of Wild Korean lettuce(Youngia sonchifolia Max.), the chemical characteristics, contents of free sugar, amino acid composition, fatty acid composition and minerals were analysed. Free sugars determined from the roots were rhamnose, fructose, glucose, sucrose maltose, melibiose and raffinose, whereas raffinose was not detected from the leaves. Of amino acid composition in the roots glutamic acid content was largest followed by histidine aspartic acid, leucine and proline. As for leaves glutamic acid was highest fellowed by aspartic acid, leucine and histidine. Mtehionine and cystine were found in low content in both roots and leaves. Major fatty acid composition in total lipid(free and bound) were linoleic, linolenic and palmitic acid in both and leaves. P, K and Ca were rich minerals contained in the roots and leaves of Wild Youngia sonchifolia Max.

• Journal of The Korean Society of Grassland and Forage Science
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• v.21 no.2
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• pp.81-88
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• 2001

To investigate C and N metabolisms in response to potassium-deficient stress during regrowth of Italian ryegrass(Lolium multiflorum L.), C and N metabolites were analyzed at day 0 (cutting date), 6, 12 and 24 days after defoliation. K-sufficient (control, +K) and K-absent (-K) nutrition solutions were applied from 7 days before defoliation, and continued for one cycle of 24 days-regrowth period. During 24 days of regrowth dry matter of regrowing shoots and remaining tissues were not significantly different between +K and -K treatment. In remaining stubble, all C compounds in both +K and -K treatment largely decreased (69% to 84% of the initial level) during the first 6 days of regrowth, and then rapidly recovered. The decline of soluble sugars and fructan in roots for the first 6 days much less in the -K medium. Amino acids, soluble and insoluble proteins in stubble also feel down during the first 6 days, thereafter actively replenished in both +K and -K treatment. The decline of nitrate in stubble prolonged to 12 days of regrowth. Initial amounts of all N compounds in roots were significantly lower in the -K medium. Higher accumulation of amino acids and soluble protein in roots in the -K medium was observed after 12 days of regrowth. In regrowing shoots, 3 all carbohydrates increased with a very similar pattern for both treatments. Nitrate was not significantly different between two treatments. Depress of soluble protein accumulation in -K medium was noteworthy after 12 days of regrowth. These results indicated that an active utilization of organic reserves occurred to support regrowth even under K deficient condition with a similar extent with K sufficient condition.