• Journal of Microbiology and Biotechnology
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• v.17 no.12
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• pp.2081-2084
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• 2007

A 2.5 kb aga gene encoding ${\alpha}$-galactosidase (${\alpha}$-Gal) from Leuconostoc mesenteroides SY1 was cloned into pSJE, an E. coli-Leuconostoc shuttle vector. The recombinant plasmid, pSJEaga, was introduced into Leuconostoc citreum KCTC3526 (ATCC49370) by electroporation. Transcription level of aga was the highest in cells grown on raffinose (1%, w/v) followed by cells grown on galactose, melibiose, fructose, glucose, and sucrose. Western blot using antibodies against ${\alpha}$-Gal showed similar results to slot-blot results and enzyme activity measurements. All the results indicated that the aga was successfully expressed in L. citreum and its transcription was under the carbon catabolite repression (CCR).

• Food Science and Biotechnology
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• v.14 no.4
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• pp.498-502
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• 2005

Three Korean soybean varieties - Shinpaldal-2, Seomoktae and Seoritae - were investigated for changes in their physical properties and the amount of functional components (i.e. isoflavones and oligosaccharides), during germination. Soybeans were germinated at $20^{\circ}C$ for 96 hr in complete darkness. The dry weights of cotyledone, hypocotyl, seed coat, and hilum of Seoritae were heavier than those of other varieties. The dry weights of the three bean varieties decreased steadily in spite of root growth. The largest amount of isoflavone content was observed from Shinpaldal-2 (1.824 mg/g), followed by Seoritae (1.216 mg/g) and Seomoktae (1.125 mg/g). Total isoflavone content increased by 13% during initial germination, and then decreased thereafter. Aglycone types such as daidzein and genistein dominated the increase in isoflavone contents. The increase in genistein content of Shinpaldal-2 was 17.5 fold compared with ungerminated soybean, while the amount of daidzein was 6.7 times as much as ungerminated Shinpaldal-2 over an 18-hr germination period. Oligosaccharide contents such as raffinose (Raf) and stachyose (Sta) rapidly decreased during germination, while the sucrose (Sue) content remained constant until 36-48 hr of germination. From these results, it was clearly shown that the germination process significantly changed the contents of functional nutrients in soybeans. Therefore, the optimization of germination process should be considered to improve the biological functionality of soybeans in food processing.

• Microbiology and Biotechnology Letters
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• v.18 no.5
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• pp.484-489
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• 1990

An intracellular inulase ( fJ-fructofuranoside fructohydrolase, EC 3.2.1.26) from Bacillus subtilis has been partially purified and its mode of action and general properties were studied. The enzyme had an apparent molecular weight of 49,000 as estimated by gel filtration and its pI point was 5.2. Substrate concentration studies showed an apparent Km of 10 mM for sucrose and of 18 mM for raffinose. The enzyme was an acid-labile protein with a pH optimum of 6.6. The optimum temperature was 50$^{\circ}$C. The enzyme acts on straight chain oligo- and poly-fructosides of the inulin series via a exo-wise cleavage mechanism, as well as on sucrose.

• Microbiology and Biotechnology Letters
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• v.18 no.5
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• pp.490-495
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• 1990

The extracellular inulinase from Bacillus spp. was purified to a single protein through a sequence of operations including ammonium sulfate fractionation, heat treatment, DEAE Sepharose C1-6B ion exchange chromatography, Sephadex 6-100 and Sephadex 6-150 gel filtration. The purified enzyme was confirmed to be a $\beta$ -D-fructofuranosidase(EC 3.2.1.26) which was much more active on sucrose than on inulin(I/S = 0.2). The maximal inulinase activity was observed at pH 6.0 and at the temperature of $50^{\circ}C$. The mo1ecular weight of the enzyme was about 56, 000. Tryptophan and histidine residues of the enzyme molecule were found to be essential for its catalytic activity.

• Food Science and Biotechnology
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• v.17 no.5
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• pp.1115-1118
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• 2008

${\alpha}$-Galactosidase gene (aga) from Leuconostoc mesenteroides SY1 was expressed in a heterologous host, Lactobacillus brevis 2.14 using an Escherichia coli-Leuconostoc shuttle vector, pSJE. pSJEaga (pSJE carrying aga) was introduced into Lactobacillus brevis 2.14 by electroporation and transformation efficiency was $1.1{\times}10^3$ per ${\mu}g$ DNA. L. brevis transformants (TFs) showed higher ${\alpha}$-galactosidase (${\alpha}$-Gal) activities than cells containing pSJE. Transcription levels of aga in L. brevis 2.14 grown on different carbon sources (1%, w/v) were examined by slot blot analysis. Aga transcript levels and ${\alpha}$-Gal activities were higher in cells grown on melibiose, raffinose, and galactose than cells on glucose, sucrose, and fructose. Western blot result showed that L. brevis 2.14 harboring pSJEaga produced much more ${\alpha}$-Gal when grown on melibiose than on glucose.

• Korean Journal of Microbiology
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• v.31 no.2
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• pp.99-104
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• 1993

Two strains of the gram-negative acetic acid bacteria, Acetobacter sp. strain CS2- AND CS5, were isolated form the traditional raw rice wine vinegar of Haenam area. The strains oxidized ethanol to acetic acid and over-oxidized acetate and lactate to $CO^{2}$ and $H ^{2}$O. They produced 2-ketogluconic acid from glucose but did not produce .gamma.-pyrones from glucose and dihydroxyacetone from glycerol. The CS strains possessed ubiquinone-9 as a major isoprenoid quinone and contained straight-chain $C_{18 :1}$, $_C{16 : 0}$, and $C _{14 : 0}$ fatty acids. The DNA base composition of the CS2 and CS5 strains was 56.2 and 57.3 mole% G + C, respectively. The isolates were grown well on methanol, gluconate, erythritol, raffinose, dulcitol and xylitol as sole sources of carbon and energy which are different from those of other Acetobacter species and producedd acid from sucrose, glycerol, fructose, inositol, mannitol, and ribose.

• Korean Journal of Food Science and Technology
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• v.24 no.6
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• pp.586-591
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• 1992

The oligosaccharide metabolism in soymilk was investigated by mixed culture with Lactobacillus acidophilus and Saccharomyces uvarum. When Saccharomyces uvarum was cultured in soywhey, change of oligosaccharide could be shown apparently. However, Lactobacillus acidophilus could not utilize oligosaccharide in soywhey for growth and lactic acid production. During the fermentation of mixed culture with Lactobacillus acidophilus and Saccharomyces uvarum, Saccaharomyces uvarum was supposed to convert oligosaccharide to monosaccharide first and then Lactobacillus acidophilus to convert these produced monosaccharide to lactic acid.

• Journal of Plant Biology
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• v.38 no.3
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• pp.251-258
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• 1995

The soluble acid invertase ($\beta$-D-fructofuranoside fructohydrolase, EC 3.2.1.26) was isolated and characterized from the hypocotyls of mung bean (Phaseolus radiatus L.). The enzyme was purified to apparent homogeneity by consecutive step using diethylaminoethyl (DEAE)-cellulose anion exchange, Concanavalin (Con) A affinity and Sephacryl S-300 chromatography. The overall purification was about 148-fold with a yield of about 15%. The finally purified enzyme exhibited a specific activity of about 139 $\mu$mol of glucose produced mg-1 protein min-1 at pH 5.0 and appeared to be a single protein by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and nondenaturing PAGE. The enzyme had the native molecular weight of 70 kD and subunit molecular weight of 70 kD as estimated by Sephadex G-200 chromatography and SDS-PAGE, respectively, suggesting that the enzyme was composed of a monomeric protein. On the other hand, the enzyme appeared to be a glycoprotein containing N-linked high mannose oligosaccharide chain on the basis of its ability to bind to the immobilized C on A. The enzyme had a Km for sucrose of 1.8 mM at pH 5.0 and maximum activity around pH 5.0. The enzyme showed highest enzyme activity with sucrose as substrate, but the activity was slightly measured with raffinose and cellobise. No activity was measured with maltose and lactose. These results indicate the soluble acid invertase is a $\beta$-fructofuranosidase.

• Journal of environmental and Sanitary engineering
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• v.15 no.4
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• pp.105-113
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• 2000

We have isolated 65 strains(2.0%) of Y. enterocolitica among 3,219 water samples from 380 spring water sites in Seoul from 1994 to 1999. The biochemical characteristics of isolated strains revealed that TSI was A/A, urea, M.R.($37^{\circ}C$), nitrate, motility($37^{\circ}C$), sorbitol, maltose, manitol, arabinose, mannose, trehalose, xylose were positive(100%) and H$_2$S, arginine, lysine, oxidase, citrate, V.P.($37^{\circ}C$), DNase, motility($37^{\circ}C$), dulcitol, adonitol, lactose and raffinose were negative(100%). In in vitro virulence test, positive rate of AAG and CRMOX were 9.2% and 4.6%, respectively. However in the virulence gene detectable gene detectable test by multiplex-PCR using ail, yst, virF genes, 65 strains were all negative, meaning that Y.enterocolitica strains from domestic spring water were not detected for the virulence. Otherwise, mutiplex-PCR which using ail, yst and subgenus-specific primer pair was the best for identifying the virulence of Y. enterocolitica.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.4
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• pp.552-557
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• 2013

Partially purified ${\alpha}$-galactosidase from Bacillus sp. LX-1 was non-covalently immobilized on a reversibly soluble-insoluble polymer, Eudragit L-100, and an immobilization efficiency of 0.93 was obtained. The optimum pH of the free and immobilized enzyme was 6.5 to 7.0 and 7.0, respectively, while there was no change in optimum temperature between the free and immobilized ${\alpha}$-galactosidase. The immobilized ${\alpha}$-galactosidase was reutilized six times without significant loss in activity. The immobilized enzyme showed good storage stability at $37^{\circ}C$, retaining about 50% of its initial activity even after 18 d at this temperature, while the free enzyme was completely inactivated. The immobilization of ${\alpha}$-galactosidase from Bacillus sp. LX-1 on Eudragit L-100 may be a promising strategy for removal of ${\alpha}$-galacto-oligosaccharides such as raffinose and stachyose from soybean meal and other legume in feed industry.