Showing papers on "Melibiose published in 2012"
TL;DR: The saccharide profiles of 5 different botanical species in 86 Italian honey samples investigated by ¹H and¹H-¹³C NMR spectroscopy allowed the identification of saccharides characterizing different honeys, and OPLS-DA models were built to highlight differences between polyfloral and high mountainpolyfloral honeys and between high mountain polyfloras and rhododendron honeys.
Abstract: The saccharide profiles of 5 different botanical species in 86 Italian honey samples were investigated by 1H and 1H–13C NMR spectroscopy. Nineteen saccharides were identified in the aqueous extracts, namely, fructose, glucose, gentiobiose, isomaltose, kojibiose, maltose, maltulose, melibiose, nigerose, palatinose, sucrose, turanose, erlose, isomaltotriose, kestose, maltotriose, melezitose, raffinose, and maltotetraose. PCA performed on NMR spectral regions, in particular between 4.400 and 5.700 ppm and the fructose signal at 4.050 ppm, revealed a partial sample grouping. The score contribution plots derived from PCA performed using the mean values for the buckets of the anomeric region for each floral source allowed the identification of saccharides characterizing different honeys. OPLS-DA models were further evaluated to confirm the previous findings. OPLS-DA models were also built to highlight differences between polyfloral and high mountain polyfloral honeys and between high mountain polyfloral and rho...
61 citations
TL;DR: The elucidation of the role levansucrase in RFO metabolism by lactobacilli allowed the conversion or hydrolysis of RFOs in food fermentations.
61 citations
TL;DR: Slow amorphous-to-crystalline transition rate is known to be important for lyoprotecting excipients when formulating a robust drug product and might make their use advantageous in this respect compared to sucrose and cellobiose.
Abstract: To study how water plasticization affects the molecular mobility and crystallization tendency of freeze-dried trehalose, sucrose, melibiose and cellobiose. Freeze-dried disaccharides were subjected to different relative humidity atmospheres and their physical stabilities were evaluated. Lyophilizate water sorption tendencies and glass transition temperatures were modeled using Brunauer-Emmett-Teller (BET) and Gordon-Taylor (GT) equations, respectively. Sucrose and cellobiose crystallization tendencies were compared by using the concept of reduced crystallization temperature (RCT), and the molecular mobilities of trehalose and melibiose were compared by measuring their T1H relaxation time constants. Based on the BET and GT models, water sorption tendency and the resulting plasticizing effect were different in sucrose when compared to the other disaccharides. Trehalose and melibiose exhibited generally slower crystallization rates when compared to sucrose and cellobiose. Amorphous melibiose was shown to be particularly stable within the studied water content range, which may have partly been caused by its relatively slow molecular mobility. Slow amorphous-to-crystalline transition rate is known to be important for lyoprotecting excipients when formulating a robust drug product. The physical stabilities of amorphous trehalose and melibiose even with relatively high water contents might make their use advantageous in this respect compared to sucrose and cellobiose.
53 citations
TL;DR: It is suggested that Aga1 and Aga2 play essential roles in the metabolism of dietary oligosaccharides and could be used for the design of galacto-oligOSaccharide (GOS) prebiotics, known to selectively modulate the beneficial gut microbiota.
Abstract: Ruminococcus gnavus belongs to the 57 most common species present in 90% of individuals. Previously, we identified an α-galactosidase (Aga1) belonging to glycoside hydrolase (GH) family 36 from R. gnavus E1 (M. Aguilera, H. Rakotoarivonina, A. Brutus, T. Giardina, G. Simon, and M. Fons, Res. Microbiol. 163:14–21, 2012). Here, we identified a novel GH36-encoding gene from the same strain and termed it aga2. Although aga1 showed a very simple genetic organization, aga2 is part of an operon of unique structure, including genes putatively encoding a regulator, a GH13, two phosphotransferase system (PTS) sequences, and a GH32, probably involved in extracellular and intracellular sucrose assimilation. The 727-amino-acid (aa) deduced Aga2 protein shares approximately 45% identity with Aga1. Both Aga1 and Aga2 expressed in Escherichia coli showed strict specificity for α-linked galactose. Both enzymes were active on natural substrates such as melibiose, raffinose, and stachyose. Aga1 and Aga2 occurred as homotetramers in solution, as shown by analytical ultracentrifugation. Modeling of Aga1 and Aga2 identified key amino acids which may be involved in substrate specificity and stabilization of the α-linked galactoside substrates within the active site. Furthermore, Aga1 and Aga2 were both able to perform transglycosylation reactions with α-(1,6) regioselectivity, leading to the formation of product structures up to [Hex]12 and [Hex]8, respectively. We suggest that Aga1 and Aga2 play essential roles in the metabolism of dietary oligosaccharides and could be used for the design of galacto-oligosaccharide (GOS) prebiotics, known to selectively modulate the beneficial gut microbiota.
45 citations
TL;DR: Besides hydrolyzing the pNPGal, Cicer α-galactosidase also hydrolyzed natural substrates such as melibiose, raffinose, and stachyose very effectively; hence, it can be exploited commercially for improving the nutritional value of soy milk.
Abstract: Glycosylated α-galactosidase (melibiase) has been purified from white chickpea ( Cicer arietinum ) to 340-fold with a specific activity of 61 units/mg. Cicer α-galactosidase showed a M(r) of 45 kDa on SDS-PAGE and by MALDI-TOF. The optimum pH and temperature with pNPGal were 4.5 and 50 °C, respectively. The K(m) for hydrolysis of pNPGal was 0.70 mM. Besides hydrolyzing the pNPGal, Cicer α-galactosidase also hydrolyzed natural substrates such as melibiose, raffinose, and stachyose very effectively; hence, it can be exploited commercially for improving the nutritional value of soy milk. Galactose was found to be a competitive inhibitor. The property of this enzyme to cleave the terminal galactose residues can be utilized for converting the group B erythrocytes to group O erythrocytes.
32 citations
TL;DR: In this article, the authors separated reducing carbohydrates in maple syrup and maple sugar by capillary electrophoresis using derivatization with 1-phenyl-3-methyl-5-pyrazolone (PMP) and the characteristics of these samples were studied.
Abstract: Reducing carbohydrates in maple syrup and maple sugar were separated by capillary electrophoresis using derivatization with 1-phenyl-3-methyl-5-pyrazolone (PMP) and the characteristics of these samples were studied. Reducing carbohydrate standards including nine monosaccharides and five disaccharides as PMP derivatives could be easily resolved by using 200 mM borate buffer (pH 10.5) as a background electrolyte. Glucose was the most abundant reducing sugar in both maple samples, and mannose was abundant relative to the other sugars. The other monosaccharides (xylose, arabinose, ribose, galactose and N-acetylglucosamine) were also detected. When maple syrup and maple sugar were treated with invertase, which removed fructose residues from the reducing ends of fructosyl saccharides, melibiose was detected, suggesting that raffinose exists in both samples. The differences of carbohydrate contents between maple syrup and maple sugar were also discussed.
21 citations
TL;DR: Findings are consistent with the notion that Gly117 plays an important role in cation binding and translocation in MelB(St), and indicate that sugar is released prior to release of the coupling cation.
Abstract: The melibiose permease of Salmonella typhimurium (MelBSt) catalyzes symport of melibiose with Na+, Li+, or H+, and bioinformatics analysis indicates that a conserved Gly117 (helix IV) is part of th...
21 citations
TL;DR: The Antarctic Bacillus sp.
Abstract: An Antarctic Bacillus sp. isolate was found to exhibit extracellular α-galactosidase activity. On the basis of the results of 16S rRNA sequencing, the strain was named Bacillus sp. LX-1. In a one-factor-at-a-time experiment, galactose, peptone and Mn 2+ were found to be the medium components that facilitated enzyme production. The new strain showed optimal α-galactosidase activity at pH 7.0 and temperature of 40°C. The enzyme exclusively hydrolyzed α-D-galactosides such as p-nitrophenyl--galactopyranoside, melibiose, raffinose and stachyose, and showed no effect with proteases such as trypsin, pancreatin, and pronase. Enzyme activity was almost completely inhibited by the presence of Ag + , Hg 2+ , Cu 2+ , and sodium dodecylsulfate (SDS) but was unaffected by β-mercaptoethanol and ethylenediaminetetraacetic acid (EDTA). The LX-1 α-galactosidase may be a promising candidate as a biocatalyst for soybean processing in food and feed industries. Key words: Antarctic, Bacillus sp., α-galactosidase, one-factor-at-a-time, biocatalyst.
16 citations
TL;DR: The findings support the previous conclusion that Gly117 plays an important role in cation binding and translocation and block the lethal effect of elevated melibiose transport in the Gly117 mutants.
Abstract: The melibiose permease of Salmonella enterica serovar Typhimurium (MelBSt) catalyzes symport of melibiose with Na+, Li+, or H+. Bioinformatics and mutational analyses indicate that a conserved Gly117 (helix IV) is a component of the Na+-binding site. In this study, Gly117 was mutated to Ser, Asn, or Cys. All three mutations increase the maximum rate (Vmax) for melibiose transport in Escherichia coli DW2 and greatly decrease Na+ affinity, indicating that intracellular release of Na+ is facilitated. Rapid melibiose transport, particularly by the G117N mutant, triggers osmotic lysis in the lag phase of growth. The findings support the previous conclusion that Gly117 plays an important role in cation binding and translocation. Furthermore, a spontaneous second-site mutation (P148L between loop4-5 and helix V) in the G117C mutant prevents cell lysis. This mutation significantly decreases Vmax with little effect on cosubstrate binding in G117C, G117S, and G117N mutants. Thus, the P148L mutation specifically inhibits transport velocity and thereby blocks the lethal effect of elevated melibiose transport in the Gly117 mutants.
16 citations
TL;DR: It is shown that the presence of one anionic charge in the polar head group does not alter the SK3 channel inhibition and provides insights into the future development of a class of migration-targeted anticancer agents.
Abstract: The SK3 channel, a member of the small conductance calcium-dependent potassium channels (SKCa), plays a central role with respect to the motility of highly metastatic cancerous cells (e.g. MDA-MB435s – breast cancer cell). Edelfosine, an ether lipid derivative, is able to partially inhibit this channel activity and thus reduce the SK3-dependent cell motility, but, due to its toxicity, analogues of this compound were highly desired. Ohmline, an edelfosine analogue that possesses a lactose unit in its polar domain, was the first efficient and non-toxic SK3 inhibitor that exhibits an amphiphilic structure. In the present work, we have modified the polar head of Ohmline by placing a disubstituted phosphate group between a disaccharide unit (lactose, maltose, and melibiose) and the glycerol ether-lipid moiety. It was first observed that this modification increases the water solubility of these compounds. All these novel compounds are efficient SK3 channel inhibitors with an activity comparable to Ohmline (patch-clamp measurements). These compounds are also able to reduce the SK3-dependent cell motility with similar efficacies to Ohmline. In a broader perspective it is shown that the presence of one anionic charge (coming from the presence of a phosphate group) in the polar head group does not alter the SK3 channel inhibition and provides insights into the future development of a class of migration-targeted anticancer agents.
13 citations
Journal Article•
TL;DR: Three thermophilic bacterial strains GCTP-1, GCMB-1 and GCDP-1 were isolated from the hot springs of Tatta Pani, Murtazabad & Darkut Pass respectively in the surroundings of Gilgit and showed optimum growth temperature 6570C.
Abstract: The importance of thermostable biomolecules in the field of biotechnology has spurred research into organisms capable of growth at high temperatures. Three thermophilic bacterial strains GCTP-1, GCMB-1 and GCDP-1 were isolated from the hot springs of Tatta Pani, Murtazabad & Darkut Pass respectively in the surroundings of Gilgit. All isolates have entire and slimy colonies while the cells were small rods, gram-negative non-motile and semi aerobic. Strains GCTP-1 showed positive results of ortho nitrophenyl-β-D-galactopyranosidase (ONPG) and gelatin hydrolysis (GEL) tests other isolates gave negative results in all tests such as ortho nitrophenyl-βD-galactopyranosidase, arginine dihydrolases, lysine decarboxlase, ornithine decarboxylases, citrate utilization, H2S production, urease, tryptophan deaminases, indole production, acetoin production, gelatin hydrolysis, Fermentation/oxidation (glucose, mannitol, inositol, sorbitol, rhamnose, sucrose, melibiose, amygdalin, arabinose) and cytochrome oxidase. All isolates were grown well at pH range 7–9, with optimum pH 7.2. However, isolates were highly thermophilic and showed optimum growth temperature 6570C
TL;DR: The presented methodology is applicable in principle to any membrane protein, provided that it can be purified and reconstituted in functional form, and appropriate substrates are available.
Abstract: The determination of protein conformational changes induced by the interaction of substrates with secondary transporters is an important step toward the elucidation of their transport mechanism. Since conformational changes in a protein alter its vibrational patterns, they can be detected with high sensitivity by infrared difference (IR(diff)) spectroscopy without the need for external probes. We describe a general procedure to obtain substrate-induced IR(diff) spectra by alternating perfusion of buffers over an attenuated total reflection (ATR) crystal containing an adhered film of a membrane protein reconstituted in lipids. As an example, we provide specific protocols to obtain melibiose and Na(+)-induced ATR-IR(diff) spectra of reconstituted melibiose permease, a sodium/melibiose co-transporter from E. coli. The presented methodology is applicable in principle to any membrane protein, provided that it can be purified and reconstituted in functional form, and appropriate substrates are available.
TL;DR: In this article, the α-Galactosidase of Aspergillus foetidus ZU-G1 was purified and compared with three major α-galactosaidase forms (α-gal I, α-al II and α-alg III) in terms of biochemical and hydrolytic properties.
Abstract: α-Galactosidase had applied in food and feed industries for hydrolyzing raffinose series oligosaccharides (RO) that are the factors primarily responsible for flatulence upon ingestion of soybean-derived products. The objective of the current work was to purify the α-galactosidase of Aspergillus foetidus ZU-G1 and compared the biochemical and hydrolytic properties of three major α-galactosidase forms (α-gal I, α-gal II and α-gal III). The molecular mass of the purified enzyme as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) was 106.3, 49.7 and 109.9 kDa, respectively. Its optimum reaction temperature was 60 °C and stable below 50 °C. The optimum pH of α-gal I and α-gal III was 5.0 and α-gal II was 4.0. Under 28 °C conditions for 24 h, α-gal I was stable at pH 4.0, α-gal II was stable at pH 6.0, and α-gal III was pH 5.0. α-Galactosidase was completely inhibited by Ag+. CuSO4·5H2O and SDS were powerful inhibitors of α-gal I and α-gal III but had little effect to α-gal II. EDTA did not strongly affect α-gal I and α-gal III, while strongly affect α-gal II. CaCl2·2H2O, MgSO4·7H2O and MnSO4·7H2O were activation for α-gal I, α-gal II and α-gal III. No significant inhibition of enzymes activity was observed in the presence of raffinose, lactose as well as other sugars tested. Synthetic substrate p-nitrophenyl-α-d-galactopyranoside was not preferentially hydrolyzed than natural substrates, such as melibiose, stachyose and raffinose. Under 40 and 50 °C incubation for 1–5 h, the stachyose of soybean milk was degraded by α-gal I, α-gal II and α-gal III and strongly hydrolyzed by α-gal II, and the raffinose of soybean milk was completely hydrolyzed by α-gal II and weakly hydrolyzed by α-gal I and α-gal III. The distinct hydrolytic and biochemical properties of α-gal I, α-gal II and α-gal III further signify the α-galactosidase of A. foetidus ZU-G1 was propitious to soybean milk and related food industry.
Patent•
19 Jun 2012
TL;DR: In this article, a Lactobacillus plantarum CLP-1 strain and a probiotic containing the same are provided to ensure excellent antiviral and antibacterial function.
Abstract: PURPOSE: A novel Lactobacillus plantarum CLP-1 strain and a probiotic containing the same are provided to ensure excellent antiviral and antibacterial function CONSTITUTION: A Lactobacillus plantarum CLP-1 strain(deposit number KACC91591P) has antiviral and antibacterial function The stain has 16S rRNA base sequence of sequence number 1 and has negative availability to galactose, esculin, melibiose, and gentibiose A probiotic contains the strain or culture liquid thereof as an active ingredient A feed additive contains the strain or culture liquid thereof as an active ingredient
TL;DR: Highly purified 1-O-IAGlc-SugAc shows maximum transferase activity with monosaccharides (mannose, glucose, and galactose), lower activity with disacchariding and trisaccharide (raffinose) and minimal enzymatic activity with oligosACcharides from the raffinose family as well.
Abstract: 1-O-(indole-3-acetyl)-β-d-glucose: sugar indoleacetyl transferase (1-O-IAGlc-SugAc) is a novel enzyme catalyzing the transfer of the indoleacetyl (IA) moiety from 1-O-(indole-3-acetyl)-β-d-glucose to several saccharides to form ester-linked IAA conjugates. 1-O-IAGlc-SugAc was purified from liquid endosperm of Zea mays by fractionation with ammonium sulphate, anion-exchange, Blue Sepharose chromatography, affinity chromatography on Concanavalin A-Sepharose, adsorption on hydroxylapatite and preparative PAGE. The obtained enzyme preparation indicates only one band of Rf 0.67 on 8% non-denaturing PAGE consisting of two polypeptides of 42 and 17 kDa in SDS/PAGE. Highly purified 1-O-IAGlc-SugAc shows maximum transferase activity with monosaccharides (mannose, glucose, and galactose), lower activity with disaccharides (melibiose, gentobiose) and trisaccharide (raffinose) and minimal enzymatic activity with oligosaccharides from the raffinose family as well. The novel acyltransferase exhibits, besides its primary indoleacetylation of sugar, minor hydrolytic and disproportionation activities producing free IAA and supposedly 1,2-di-O-(indole-3-acetyl)-β-glucose, respectively. Presumably, 1-O-IAGlc-SugAc, like 1-O-indole-3-acetyl-β-d-glucose-dependent myo-inositol acyltransferase (1-O-IAGlc-InsAc), is another member of the serine carboxypeptidase-like (SCPL) acyltransferase family.
TL;DR: An Antarctic bacterial isolate displaying extracellular α-galactosidic activity was named Paenibacillus sp.
Abstract: An Antarctic bacterial isolate displaying extracellular α-galactosidic activity was named Paenibacillus sp. LX-20 based on 16S rRNA gene sequence analysis. Optimal activity for the LX-20 α-galactosidase occurred at pH 6.0-6.5 and 45°C. The enzyme immobilized on the smart polymer Eudragit L-100 retained 70% of its original activity after incubation for 30 min at 50°C, while the free enzyme retained 58% of activity. The enzyme had relatively high specificity for α-D-galactosides such as p-nitrophenyl-α-galactopyranoside, melibiose, raffinose and stachyose, and was resistant to some proteases such as trypsin, pancreatin and pronase. Enzyme activity was almost completely inhibited by Ag(+), Hg(2+), Cu(2+), and sodium dodecyl sulfate, but activity was not affected by β-mercaptoethanol or EDTA. LX-20 α-galactosidase may be potentially useful as an additive for soybean processing in the feed industry.
TL;DR: The gene mel1, encoding α-galactosid enzyme in Schizosaccharomyces pombe, and the gene bgl2, encoding and α-glucosidase in Trichoderma reesei, were isolated and co-expressed in the industrial ethanolproducing strain of Saccharomyceces cerevisiae and the resulting strains were able to grow on cellobiose and melibiose through simultaneous production of sufficient extracellular β-gl
Abstract: The gene mel1, encoding alpha-galactosidase in Schizosaccharomyces pombe, and the gene bgl2, encoding and beta-glucosidase in Trichoderma reesei, were isolated and co-expressed in the industrial ethanol-producing strain of Saccharomyces cerevisiae. The resulting strains were able to grow on cellobiose and melibiose through simultaneous production of sufficient extracellular alpha-galactosidase and beta-glucosidase activity. Under aerobic conditions, the growth rate of the recombinant strain GC 1 co-expressing 2 genes could achieve 0.29 OD600 h(-1) and a biomass yield up to 7.8 g l(-1) dry cell weight on medium containing 10.0 g l(-1) cellobiose and 10.0 g l(-1) melibiose as sole carbohydrate source. Meanwhile, the new strain of S. cerevisiae CG 1 demonstrated the ability to directly produce ethanol from microcrystalline cellulose during simultaneous saccharification and fermentation process. Approximately 36.5 g l(-1) ethanol was produced from 100 g of cellulose supplied with 5 g l(-1) melibose within 60 h. The yield (g of ethanol produced/g of carbohydrate consumed) was 0.44 g/g, which corresponds to 88.0% of the theoretical yield.
TL;DR: This study has prepared membrane fraction of this bacterium and demonstrated that the enzyme responsible for D -glucose and lactose oxidation was present in this fraction, and it effectively oxidized D-glucoses and D-allose.
Abstract: Previously we reported the production of lactobionic acid by resting cells of the Acetobacter orientalis strain KYG22. In the present study we have prepared membrane fraction of this bacterium and demonstrated that the enzyme responsible for D -glucose and lactose oxidation was present in this fraction, and it effectively oxidized D-glucose and D-allose. The activity against other monosaccharides was relatively low. The enzyme also displayed low activity against disaccharides, with the exception of melibiose.
TL;DR: Knowing plasmid behavior in stressful conditions, like carbon source availability, has allowed an early insight into carbohydrate starvation as a curing agent for bifidobacteria, which could be important not only in genetics and ecology but also in food-grade and pharmaceutical applications for the development of cloning and expression vector systems.
Abstract: Bifidobacteria are indigenous components of human and animal gastrointestinal microbiota, and their health-promoting benefits have long been recognized Of the 36 currently described species of the Bifidobacterium genus, 8 contain plasmids, most of which are cryptic It is possible that plasmid presence is related very closely to environmental change, so in conditions of stress this presence could be specifically controlled For plasmid-positive Bifidobacterium pseudolongum subsp globosum RU809/1, the influence of the type and concentration of the carbohydrate source is evident in the dramatic pVS809 curing effect when growth is conducted in the presence of 015% (w/v) glucose, lactose, maltose, melibiose, raffinose or starch The effect is linked to carbohydrate starvation, not to carbohydrate abundance, and is independent of biomass growth Plasmid curing was achieved after one or two consecutive transfers, also in cells grown on medium containing 015% arabinose, fructose, galactose and sucrose, but not mannose, ribose or xylose Knowing plasmid behavior in stressful conditions, like carbon source availability, has allowed an early insight into carbohydrate starvation as a curing agent for bifidobacteria Furthermore, knowledge of plasmid behavior in stressful conditions could be important not only in genetics and ecology but also in food-grade and pharmaceutical applications for the development of cloning and expression vector systems for bifidobacteria
Journal Article•
TL;DR: TP-1 gave positive results for ortho Nitrophenyl-β-D-Galactopyranosidase (ONPG) and Gelatin hydrolysis (GEL) while other tests such as Arginine dihydrolases, Lysine decarboxlase, OrnithineDecarboxylases, H2S production, Urease, Tryptophan deaminases and Citrate utilization were negative.
Abstract: A thermophilic facultatively anaerobic bacterium (TP-1) was isolated from the Tatta Pani hot spring in Azad Kashmir. The isolate had entire and slimy colonies while the cells were small rods and gram-positive. Phylogenetic analysis based on partial 16S rRNA gene sequence comparisons showed high levels of similarity of the TP-1 (> 95%) with Geobacillus pallidus. Optimum temperature and pH for the growth of the strain TP-1 were found to be 65 o C and 7.0 respectively. TP-1 gave positive results for ortho Nitrophenyl-β-D-Galactopyranosidase (ONPG) and Gelatin hydrolysis (GEL) while other tests such as Arginine dihydrolases, Lysine decarboxlase, Ornithine decarboxylases, H2S production, Urease, Tryptophan deaminases, Indole production, Acetoin production, Fermentation/oxidation (Glucose, Mannitol, Inositol, Sorbitol, Rhamnose, Sucrose, Melibiose, Amygdalin, Arabinose) and Citrate utilization were negative.
01 Jan 2012
TL;DR: Using three-phase partitioning flowed by Sephadex G-100 chromatography, a form of α-galactosidase from Rhizopus sp.A01 grown on bean dregs broth was purified to homogeneity with a 6.7-fold increase in specific activity and 46% recovery.
Abstract: Using three-phase partitioning flowed by Sephadex G-100 chromatography,a form of α-galactosidase from Rhizopus sp.A01 grown on bean dregs broth was purified to homogeneity with a 6.7-fold increase in specific activity and 46% recovery.The enzyme was showed a monomer with apparent molecular mass of 87.6kDa by SDS-polyacrylamide gel electrophoresis and gel filtration.The α-galactosidase had high activity against p-nitrophenyl-α-d-galactopyranoside(pNPGal) but had slight activity for melibiose and raffinose,and the optimal activity was observed at pH 5.0 and 55℃.The kinetic parameters Km and kcat/Km were 2.56mmol/L and 4.74×104L/mol?s with pNPGal,and the rate of hydrolysise for melibiose was 3.4 times as much as that for raffinose.The enzyme activity was inhibited by all tested metal ions at 5.0mmol/L,and almost completely by Ca2+,Cu2+,Fe3+,Hg+ and Mn2+ among them.The α-galactosidase was highly stable over pH range of 4.5-9.0 at 25℃,and its activity retained approximately 48% of the original activity after incubation for 120min at 55℃.
Patent•
27 Apr 2012
TL;DR: In this paper, compositions and uses thereof as a supplementary bee food for increasing the MGO and/or UMF number in honey; said compositions comprise: a) from 0.0001% to 30% by weight of methyl glyoxal-1,1-dimethylacetal, methylglyoxal, dihydroxyacetone or 2,5dihydroxydioxane-2,5-dimethanol; and b) a sugar such as arabinose, 2-desoxy-D-glucose, fructose, fucose and man
Abstract: Disclosed are compositions and uses thereof as a supplementary bee food for increasing the MGO and/or UMF number in honey; said compositions comprise: a) from 0.0001% to 30% by weight of methylglyoxal-1,1-dimethylacetal, methylglyoxal, dihydroxyacetone or 2,5-dihydroxydioxane-2,5-dimethanol; and b) a sugar such as arabinose, 2-desoxy-D-glucose, 2-desoxy-D-ribose, fructose, fucose, galactose, mannose, sorbose, adonit, dulcet, erythit, inosit, mannit and/or sorbit, xylit, galacturonic acid, gluconic acid-lactone, glucuronic acid lactone, cellubiose, lactose, lactulose, maltose, melibiose, raffinose, saccharose, trehalose, amylose, inulin or natural or synthetic mixture of these sugars or other types of honey. Further disclosed is a method of feeding Manuka honey collecting bees which comprises using a composition as defined above close to a beehive of these bees.
Patent•
23 Mar 2012
TL;DR: In this paper, the authors proposed a method for reducing skin pigmentation using non-digestible oligosaccharides, such as melibiose, raffinose, stachyose, lactulose, galacto- oligosAC, fructo-oligosACcharide, oligofructose or inulin.
Abstract: The present invention provides cosmetic and pharmaceutical compositions and therapies capable of reducing skin pigmentation and valuable in treating and managing disorders of skin pigmentation. The invention uses safe and well tolerated non- digestible oligosaccharides as the active agents providing numerous advantages over the harsh chemicals of previously available compositions. The oligosaccharides are preferably selected from melibiose, raffinose, stachyose, lactulose, galacto- oligosaccharide, fructo-oligosaccharide, oligofructose or inulin. A further embodiment provides methods of treating skin inflammation using oligosaccharides.
TL;DR: CK-2165 strain was found to be closely related to G. oxydans based on the result of phylogenetic analysis using 16S rDNA sequence and the culture conditions were optimized for industrial production.
Abstract: Miglitol, a well-known therapeutic intervention agents for diabetes, exhibits competitive inhibitory activityagainst α-glucosidase and it is usually produced through three sequential steps including chemical and bioconversionprocesses. Gluconobactor oxydans ( G. oxydans ) belonging to acetic acid bacteria biologically, converts 1-deoxy-1 -(2-hydroxyethylamino)-D-glucitol (P1) into a key intermidiate, 6-(2-hydroxyetyl) amino-6-deoxy-α-L-sorbofuranose (P2) by incomplete oxidation. In this study, we identified and optimized fermentation conditions of CK-2165, that was selected in soil samples by comparing the bioconversion yield. CK-2165 strain was found to be closely relatedto G. oxydans based on the result of phylogenetic analysis using 16S rDNA sequence. Utilization of API 20 kits revealed that this strain could use glucose, mannose, inositol, sorbitol, rhamnose, sucrose, melibiose, amygdalin andarabinose as carbon sources. The culture conditions were optimized for industrial production and several important factors affecting bioconversion rate were also tested using mycelial cake. Cell harvested at the late-stationary phaseshowed the highest bioconversion yield and MgSO
01 Jan 2012
TL;DR: A phylogenetic tree constructed on the basis of 16S rRNA gene sequence showed that the Streptomyces spp.
Abstract: A new bacterial species is described, for which we propose the name Streptomyces alkaliscabies. This organism causes a scab disease of potatoes (Solanum tuberosum). The alkaline scab symptoms caused by this organism are indistinguishable from the symptoms of common scab caused by Streptomyces scabies. In culture, S. alkaliscabies is distinct from other scab-causing Streptomyces species, having flexuous spore chains and grey mass colour with non-diffusible pigments. S. alkaliscabies grows on agar media at pH 7-11 (versus pH 5.0 for S. scabies) and has high utilization of all tested sugars including mannitol, sucrose, glucose, raffinose, fructose, melibiose, cellulose, maltose and lactose as carbon source. It is intolerant to 1% phenol and salinity (NaCl at 5, 6 and 7%), melanoid pigments are produced from peptone-iron agar and tyrosine, it degrades arbutin and allantoin and is sensitive to thallium acetate at 100 µg/ml, streptomycin (25 µg/ml), oleandomycin (100 µg/ml) and penicillin (10 IU/ml) and tolerates thallium acetate at 10 µg/ml. The 16S-23S ITS region sequence was 466 bp in length and showed relatively low sequence similarity, less than 60%, with other strains. A phylogenetic tree constructed on the basis of 16S rRNA gene sequence showed that the Streptomyces spp. that cause potato scab, including S. scabies, S. acidiscabies, S. turgidiscabies, S. reticuliscabie, S. stelliscabiei, S. chiniscabies and S. europaeiscabies, constitute unique branches. It is evident that strain 8 (S. alkaliscabies) forms a distinct phyletic line from known pathogenic strains.