• Preventive Nutrition and Food Science
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• v.3 no.4
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• pp.320-323
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• 1998

Lysozyme was covalentyl conjugated with galactomannan through a amino-carbonyl reaction between the lysine $\varepsilon$-amino groups of lysozyme and the reducing ends of galactomannan at a relative humidity of 79% and 6$0^{\circ}C$. The resulting lysozyme-galactomannan conjugate (LGC) was investigated for its antibacterial activity against Escherichia coli. Lysozyme alone did not exhibit antibacterial activity against E. coli. in contrast , significant bactericidal effect was observed for LGC, depending on the reaction temperature. The degree of conjugation between lysozyme and galactomannan was dependent on the incubation time, which affected the antibacterial efficiency against E. coli. This study demonstrated that the amino-carbonyl reaction between lysozyme and galactomannan could be a potential tool to modify lysozyme toward broadening its antibacterial spectrum to Gram-negative bacteria.

• Preventive Nutrition and Food Science
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• v.17 no.3
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• pp.192-196
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• 2012

This study investigated the effects of galacomannans (guar gum, tara gum, and locust bean gum) on the rheological properties of buckwheat starch pastes under steady and dynamic shear conditions. The power law and Casson models were applied to describe the flow behavior of the buckwheat starch and galactomannan mixtures. The values of the apparent viscosity (${\eta}_{a,100}$), consistency index (K), and yield stress (${\sigma}_{oc}$) for buckwheat starch-galactomannan mixtures were significantly greater than those for the control, indicating that there was a high synergism of the starch with galactomannans. The magnitudes of storage modulus (G') and loss modulus (G") for the starch-galactomannan mixtures increased with increasing frequency (${\omega}$). The dynamic moduli (G', G"), and complex viscosity (${\eta}^*$) for the buckwheat starch-galactomannan mixtures were significantly higher than those for the control.

• Journal of Microbiology and Biotechnology
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• v.2 no.3
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• pp.204-208
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• 1992

Six kinds of oligosaccharides were obtained from the hydrolysate of copra galactomannan by a purified extracellular $beta$-mannanase from Penicillium purpurogenum. These oligosaccharides were identified as M-M, M-M-M, M-M, M-M-M-M, M-M-M-M-M and M-M-M-M-M-M; where G- and M- represent $\alpha$-l,6-D-galactosidic and $beta$-l,4-mannosidic linkages, respectively. The mode of action of mannanase on galactomannan is discussed on the basis of the structure of these oligosaccharides.

• Preventive Nutrition and Food Science
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• v.7 no.2
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• pp.139-145
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• 2002

Hen egg-white lysozyme, ovalbumin, egg-yolk phosvitin, acid-precipitated soy protein and $\alpha$$_{sl}$ milk casein were covalently linked with galactomannan through a controlled dry-heating at 6$0^{\circ}C$ under 79% relative humidity without any chemical reagent. Neoglycosylation by the covalent binding of polysaccharide chains brought a significant improvement into the surface functionalities of food proteins. Excellent emulsifying properties and foaming properties were observed in all protein-galactomannan conjugates. Bacterial mutagenesis tests and animal dose test were done to evaluate the food safety of the protein-galactomannan conjugates. The neo-glycoproteins were negative for Ames test using Salmonella typhimurium TA100 (hisG46) and TA98 (hisD3052) strains, and rec-assay using Bacillus subtilis Hl7 (rec) and M45 (re $c^{+}$) strains. All substances were also nontoxic for oral administration to rats. L $D_{50}$ 's of these substances were all more than 7.5 g/kg body-weight of rat. No effect was also observed in the weight increases and the concentrations of total cholesterol, triglyceride and phospholipids in blood serum of the administrated rats with 7.5 g/kg conjugates. Thus, Maillard-type protein-polysaccharide conjugates prepared by covalent attachment of galactomannan to food proteins were proposed to be useful as a safe functional biopolymer in this study.y.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.5
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• pp.844-850
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• 1997

$\alpha$-Galactosidase was partially purified from the culture filtrate of pichia guilliermondii by Mannobiose-Sepharose affinity column chromatography. The galactosidase exhibited maximum activity at pH 4.5 and 4$0^{\circ}C$, and was stable in the pH and temperature ranges of 4 to 5.5 and 30 to 6$0^{\circ}C$, respectively. The enzyme was inhibited by $Hg^{2+}$ and $Ag^{2+}$. The enzyme activity was ot affected considerably by treatment with other metal compounds. The enzyme hydrolyzed melibiose to galactose and glucose, raffinose to galactose and sucrose, and $Gal^{3}Man_{3}(6^{3}-$\alpha$-galactosyl-1,4-mannotriose)$ to galactose and mannotriose. On the contrary, it could not hydrolyze $Gal^{3}Man_{4}(6^{3}-galactosyl-1,4-$\alpha$-mannotetraose)$.

• Journal of Microbiology and Biotechnology
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• v.14 no.4
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• pp.863-867
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• 2004

$\alpha$-Galactosidase from A. oryzae DR-5 was induced in the presence of melibiose, raffinose, galactose, and locust bean galactomannan. The enzyme was purified to homogeneity by precipitation with acetone followed by ion-exchange chromatography using DEAE-Sephacel. The purified enzyme showed a single band in both nondenaturing-PAGE and SDS-PAGE. The enzyme was a glycoprotein in nature by activity staining. The molecular weight of the purified enzyme was 93-95 kDa by SDS-PAGE. The enzyme exhibited the optimum pH and temperature at 4.7 and $60^\circ{C}$, respectively. $\alpha$-Galactosidase activity was strongly inhibited by $Ag^{2+}, Hg^{2+}, Cu^{2+}$, and galactose. EDTA, 1,10-phenanthraline, and PMSF did not inhibit the enzyme activity, whereas N-bromosuccinimide completely inhibited enzyme activity. Investigation by TLC showed complete hydrolysis of stachyose and raffinose in soymilk in 3 h at pH 5.0 and $50^\circ{C}$.

• The Korean Journal of Ecology
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• v.28 no.3
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• pp.157-161
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• 2005

In order to investigate the geographical variation of Glycine soja distributed in southern area of Korean peninsula, 8 local populations(Sokcho, Wonju, Mt. Chiak, Cheongju, Andong, Taegu, Ulsan, Sacheon), which located from $34^{\circ}50'00"N$ to $38^{\circ}12'00"N$, were selected according to their latitudes and geographical distances. The seeds of these populations were collected and their contents of mannose and galactose were investigated, Mannose contents in the seeds were variable in the range between the highest 460.00 mg/g (Andong) and the lowest 55.23 mg/g(Sacheon). The contents of galactose were represented remarkable differences from 67.17 mg/g(Sacheon) to 387.50 mg/g(Ulsan) also. The local populations were classified into 3 types such as the middle southern inland type (Andong, Taegu), the middle northern type(Wonju, Mt. Chiak, Cheongju) and the coastal type(Sokcho, Ulsan, Sacheon) according to the ratio of mannose and galactose, which indicate the hardness of seeds in Leguminosae, ranged from 0.41 to 1.73. Particularly, those of middle southern inland populations represented the high values compared with those of other populations.

• Microbiology and Biotechnology Letters
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• v.32 no.4
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• pp.347-351
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• 2004

Hydrolysis of manno-oligosaccharides and galactomannan was studied with the purified Bacillus subtilis WL-7 mannanase from recombinant Eschericoli. The predominant products of hydrolysis were mannose, mannobiose and mannotriose. The enzyme could hydrolyze $\beta$-1 A-linked manno-oligosaccharides larger than mannobiose, but was not active on mannobiose. When the mannanase hydrolyzed manno-oligo saccharides of degree of polymerization(DP) 4-6, it was more active on the substrate of higher DP. Based on analysis of transient reaction products by TLC, the enzyme was found to have a preference for internal $\beta$-IA-mannosidic linkages, which are the central mannosidic bond of mannotetraose and the two middle mannosidic bonds of mannopentaose. The $\beta$-l A-mannosidic bonds situated at the second and fourth positions from the nonreducing end of mannohexaose were preferenhydrolyzed by the mannanase. Locust bean gum(LBG) was enzymatically hydrolyzed with higher efficiency than guar gum, resulting that amount of reducing sugars was liberated more efficiently from LBG than guar gum with same activity of mannanase.

• Proceedings of the Korean Nutrition Society Conference
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• 2003.05a
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• pp.273.2-273.2
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• 2003

• Proceedings of the Zoological Society Korea Conference
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• 2001.10a
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• pp.151.4-151
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• 2001