• Korean Journal of Soil Science and Fertilizer
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• v.23 no.1
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• pp.21-25
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• 1990

The amounts of monosaccharides in acid hydrolysates of decomposing plant residues under laboratory conditions were determined. Straw of cereal rice and barley, wild grass cutting, and litters of deciduous and coniferous forest trees were treated to decompose for 90 days. Samples for the analysis of mono-saccharides were taken at 3 different periods of incubation. 1. Fractions of monosaccahrides in plant residues steadily decreased with the time of decomposition. In some samples there appeared an intermediate stages where the fractions reached the highest level. 2. Decomposition of barley straw occured at a faster rate than that of rice straw, and so did the decomposition of deciduous litter than that of coniferous litter. 3. Cereal crop residues of rice and barley were richer in monosaccharides than residues of wild grass cutting and forest litters. 4. Distiction between monosaccharides of plant origin and those of microbial origin was not possible to make in this study. 5. Glucose was the predominent monosaccharide and fucose was the monosaccharide contained in the smallest amount. No measurable ribose was detected from any sample. 6. The relative proportion of galactose in creased with the time of incubation. 7. In general, the proportion of fucose decreased with time and so did that of rhamnose, rhamnose of rice straw residue being the exception. 8. The orders of abundance of monosaccharides after decomposition of 90 days were as the following: in rice straw; glucose > xylose > arabinose > galactose > rhamnose > mannose > fucose, in barley straw; glucose > xylose > arabinose > galactose> mannose > rhamnose > fucose, in wild grass cutting; glucose > xylose > galactose arabinose> rhamnose mannose > fucose, in deciduous litter; glucose > arabinose > xylose galactose > mannose > rhamnose = fucose, and in coniferous litter; glucose > xylose > galactose > arabinose mannose > rhamnose > fucose.

• The Microorganisms and Industry
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• v.20 no.3
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• pp.70-73
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• 1994

Effects of 13 organic compounds including glucose, fructose, xylose, glutamate, succinate, malate, glycine, lactate, acetate, pyruvate, citrate, formate and cis-aconitate on the oxidation of thiosulfate and the availability of these compounds as the substrate for the respiration by Thiobacillus ocncretivorus, which is known to be an obligated autotroph, were studied. Malate nad glycine at 0.5 per cent concentration nearly doubled the thiosulfate oxidation compared to the control. No other organic substances enhanced the thiosulfate oxidation compared to the control. No other organic substances enhanced the thiosulfate oxidation. Moreover, some 30 to 40 per cent decrease was recorded by fructose, sulfate-salts medium, some 30 to 40 per cent decrease was recorded by fructose, citrate, xylose, malate, flucose, glutamate and succinate. No respiration could occur when formate and pyruvate were supplied as the substrate for respiration. But it was obvious that flucose, fructose, xylose, glutamate, malate, citrate and succinate could be used as the substrate for respiration to some extent, regarding the fact that some increase in respiration rates could be recorded compared to the result from the salts medium, where neither thiosulfate nor orgnic compounds were added. Thus, it was postulated that this organism could possibly be converted into mixotroph or hetrotroph if appropriate conditions could be prepared.

• KSBB Journal
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• v.4 no.2
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• pp.74-77
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• 1989

To increase the volumetric productivity a contimuous cell-recycled system was implemented. Cell concentrations between 9.2 and 15.0 g/1 were obtatined in the continuous fermentor study. At a 4% xylose feed and a specific oxygen supply rate(SOSR) of 1.04 g O2.hr-g DCW the ethanol yield was 0.36% at dilution rate. This represented a 26-% increase over that of th batch fermentation.

• Journal of environmental and Sanitary engineering
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• v.4 no.2 s.7
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• pp.27-32
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• 1989

In orde to investigate free sugar, sugar alcohol, amino acid and mineral contents of edible mushrooms, hentinus edodes, Auricula-Jude and Coriolus Versicolor were analyzed. 1. In each of the three mushrooms, glucose, fructose, xylose, trehalose, mannose and mannitol were identified and in the hentinus edodes and Auricula-jude, the major free sugar was trehalose, respectively and increasing sequence in amount of free sugars were mannitol, mannose, fructose, glucose, on the other hand that lowest amount was Xylose. The relatively richest were glucose, fructose, trehalose, mannose, on the other hand lower amount of sample, Coriolus Versicolor were mannitol and Xylose. 2. In each of the three samples, essential amino acids were high amounts, especially good taste component, glutamic acid was higher. 3. The mineral p Contents$(925\~115mg)$ were highest and Mg was higher amount, in hentinus edodes and Auricula-jude, K, Na, Ca, Cu, Zn, etc were identified, In Coriolus versicolor, K content was highest, on the other hand, Sequence of mineral amount was Ca, Fe and Na.

• Journal of Animal Science and Technology
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• v.63 no.1
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• pp.191-193
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• 2021

Lactococcus lactis is a fermentative lactic acid bacterium that is used extensively in food fermentations. The L. lactis strain K_LL005 was isolated from the grasshopper (Oxya chinensis sinuosa) gut in Korea. In this study, we reported the complete genome sequence of Lactococcus lactis K_LL005. The final complete genome assembly consist of one circular chromosome (2,375,093 bp) with an overall guanine + cytosine (G + C) content of 35.0%. Annotation results revealed 2,281 protein-coding sequences (CDSs), 19 rRNAs, and 68 tRNA genes. Lactococcus lactis K_LL005 has a gene encoding xylose metabolism such as xylR, xylA, and xylB (xylRAB).

• Applied Biological Chemistry
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• v.26 no.4
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• pp.222-230
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• 1983

This study was designed to develop a process for the immobilization of xylose isomerase(D-xylose ketol isomerase, EC 5.3.1.5) from Streptomyces griseolus previously isolated by the authors and its application on a pilot plant scale for the production of high fructose corn syrup. The biomass which has endo-excreted xylose isomerase was homogenized under a pressure of $500kg/cm^2$ and 90.8% of the enzyme recovery of the native activity was obtained as compared to 54.7% recovery by the lysozyme treatment. Ionic bonding method was adopted for the enzyme immobilization due to its many reported merits. It was found that the porous resins such as Diaion HP 20, Duolite A-7, Amberlite IRA 93 and 94 were effective in immobilizing the enzyme. In addition, it was disclosed that the regeneration form of $BO_4--$ is effective for Amberlite IRA 93 and $HCO_3-$ for Diaion HP 20. Optimal immobilization condition for Amberlite IRA 93 was pH 8.0 and $55^{\circ}C$ yielding 80.6% of immobilization. Activity decay test showed half life of the immobilized enzyme with Amberlite IRA 93 was more than 24 days at $65^{\circ}C$. The carrier was evaluated to be resuable and its result showed the relative immobilization yields were 98.2, 93.3, 90.7 and 87.5%, respectively at second, third, forth and fifth rebinding test of the enzyme on Amberlite IRA 93. Optimal temperature of the immobilized enzyme was slightly lowered and the range widened to $60\sim70^{\circ}C$, while optimal pH moved toward $8.0\sim8.3$ in its isomerization reaction. The trial production result of high fructose corn syrup in pilot scale immobilization showed that one liter of immobilized xylose isomerase (350 IXIU/ml-R) is capable producing about 293l high fructose corn syrup(75% dry substance) in 30 days.

• Applied Biological Chemistry
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• v.39 no.6
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• pp.443-448
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• 1996

In order to investigate the function of xylA promoter(Pxyl) as regulatory region Pxyl-lacZ fusion gene was constructed by the insertion of xylA promoter to the multiple cloning site of upstream of lacZ gene in a multicopy numbered plasmid pMC1403 containing promoterless lac operon, which was designated pMCX191, and Pxyl-lacZ fragment from pMCX191 was inserted to low copy numbered plasmid pLG339, designated pLGX191. The expressions of ${\beta}-galactosidase$ in these recombinant plasmids containing Pxyl-lacZ fusion gene were induced strongly by the addition of xylose, repressed by the addition of 0.2% glucose in the presence of xylose. The catabolite repressions were derepressed by the addition of 1 mM cAMP as same as native xylA gene. The fragment of xylA promoter was partially deleted from the upstream of xylA promoter by exonuclease III to investigate the regulation site of xylA promoter and the degrees of deletion derivatives of xylA promoter were analyzed by the DNA base sequencing. By the investigations of the induction by xylose, repression by glucose and derepression by cAMP on xylose isomerase production, the regulation site of xylA promoter may be located in segment between -165 and -59 bp upstream from the initiation site of xylA translation.

• Journal of the East Asian Society of Dietary Life
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• v.25 no.5
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• pp.822-829
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• 2015

The purpose of this study was to evaluate the biological activities and quality properties of macaroons made with GABA rice powder and xylose. GABA rice powder was added to macaroons at weight percentages of 0, 2.5, and 3.5%. Hunter's color values ($L^*$, $a^*$, $b^*$), total sugar contents, total phenolics, ABTS and DPPH radical scavenging activities, textures, and sensory characteristics supplemented with different xylose and GABA rice powder contents were measured. As the ratio of GABA rice powder in macaroons increased, total phenol contents and ABTS and DPPH radical scavenging activities increased. In the texture profile analysis, fracturability and brittleness were lower as GABA rice powder content increased. In the sensory evaluation, significant differences (p<0.05) were observed in color, sweetness, texture, and overall acceptability depending on the addition of GABA rice powder to macaroons. Overall qualities of macaroons were different from GABA rice powder and xylose added ones. Therefore, xylose and GABA rice powder may be used to make healthy macaroons.

• Journal of Life Science
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• v.26 no.11
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• pp.1269-1274
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• 2016

The oyster is called "milk of sea" which is abundant in taurine, glycogen, cellenium. It could be used in making natural source. Recently, consumers have more interest in natural source because of their diverse preference and its special taste. The goal of this study is to optimize maillard reaction condition for manufacturing natural seasoning using oyster and oyster cooking drip hydrolysate. The result was judged by browning degree and pyrazine, which is flavor components when food heating. Hydrolysate and sugar react according primarily to type of sugar - glucose, xylose and fructose. Xylose was selected as best sugar of browning degree. In the case of sugar contents, all conditions over 1% of sugar contents are almost same. Therefore, the lowest 1% of sugar was selected as appropriate condition. According to the reaction with different temperature, browning degree and pyrazine contents had been increased over $60^{\circ}C$, but the product at $120^{\circ}C$had off-flavored. So, $100^{\circ}C$ is the best condition for the browning reaction. And in accordance with different reaction time, after 6 hours, there was no change in pyrazine and browning reaction. Therefore, to manufacture natural seasoning source, it is optimal to react xylose for maillard reaction at $100^{\circ}C$ for 6 hr with hydrolysate of oyster and oyster cooking drip.

• The Korean Journal of Mycology
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• v.14 no.4
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• pp.257-263
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• 1986

So as to clarify the biodegradation mechanism of lignin, lignin biodegradability among four white-rot fungi, Pleurotus ostreatus 1,2,3, and Polyporus versicolor were compared each other by simple plate test method, so that P. ostreatus 2 and P. versicolor exhibited the most wide clear zone. And to investigate the degree of lignin depolymerization, they were grown in lignin­media where various carbohydrates were added, then that was analyzed through column chromato­graphy. In consequence, P. ostreatus 2 and 3 showed more excellent effect of lignin depolymerization among those 4 white-rot fungi, and also in culture media in which glucose, cellobiose and xylose were added. When culture filtrates of the same media were scanned at UV range, there were no peak at 280 nm in the culture filtrate of P. ostreatus 2 and 3 where glucose, cellobiose and xylose were added. At the same time, culture filtrate, in which lignin was only contained as a carbon source, showed browning in color, whereas culture media with glucose, cellobiose and xylose in addition to lignin became yellowish (that is, decolorization). From above results, it might be assumed that polymerization and browning of lignin were decreased and lignin biodegradability was increased, when grown in lignin media where various carbohydrates were added.