59-23-4Relevant articles and documents
Hydrolysis of β-galactosyl ester linkage by β-galactosidases
Kiso, Taro,Nakano, Hirofumi,Nakajima, Hirofumi,Terai, Tadamasa,Okamoto, Katsuyuki,Kitahata, Sumio
, p. 1702 - 1706 (2000)
p-Hydroxybenzoyl β-galactose (pHB-Gal) was synthesized chemically to examine the hydrolytic activity of β-galactosyl ester linkage by β-galactosidases. The enzyme from Penicillium multicolor hydrolyzed the substrate as fast as p-nitrophenyl β-galactoside (pNP-Gal), a usual substrate with a β-galactosidic linkage. The enzymes from Escherichia coli and Aspergillus oryzae hydrolyzed pHB-Gal with almost the same rates as pNP-Gal. The enzymes from Bacillus circulans, Saccharomyces fragilis, and bovine liver showed much lower activities. pH-activity profiles, inhibition analysis, and kinetic properties of the enzymic reaction on pHB-Gal suggested that β-galactosidase had only one active site for hydrolysis of both galactosyl ester and galactoside. The Penicillium enzyme hydrolyzed pHB-Gal in the presence of H218O to liberate galactose containing 18O. This result suggests the degradation occurs between the anomeric carbon and an adjacent O atom in the ester linkage of pHB-Gal.
Cooperation of β-galactosidase and β-N-acetylhexosaminidase from bifidobacteria in assimilation of human milk oligosaccharides with type 2 structure
Miwa, Mika,Horimoto, Tomohiro,Kiyohara, Masashi,Katayama, Takane,Kitaoka, Motomitsu,Ashida, Hisashi,Yamamoto, Kenji
, p. 1402 - 1409 (2010)
Bifidobacteria are predominant in the intestines of breast-fed infants and offer health benefits to the host. Human milk oligosaccharides (HMOs) are considered to be one of the most important growth factors for intestinal bifidobacteria. HMOs contain two
SBA-15 supported ionic liquid phase (SILP) with H2PW12O40- for the hydrolytic catalysis of red macroalgal biomass to sugars
Malihan, Lenny B.,Nisola, Grace M.,Mittal, Neha,Lee, Seong-Poong,Seo, Jeong Gil,Kim, Hern,Chung, Wook-Jin
, p. 33901 - 33909 (2016)
A supported ionic liquid phase (SILP) catalyst for biomass hydrolysis was prepared via immobilization of an acidic ionic liquid (IL) with a phosphotungstic counter-anion H2PW12O40- (HPW) on ordered mesoporous silica (SBA-15). Characterization results from XRD, N2 physisorption, FT-IR, TGA and SEM/TEM image analyses confirmed the successful preparation of the SILP catalyst (SBA-IL-HPW). Meanwhile, its catalytic performance was evaluated in terms of sugar production from the hydrolysis of different biomasses in water. Under optimal hydrolysis conditions, SBA-IL-HPW yielded 73% d-galactose from agarose and 58% d-glucose from cellobiose. Moreover, SBA-IL-HPW effectively hydrolyzed the red macroalgae G. amansii as it afforded 55% total reducing sugar and 38% d-galactose yields. SBA-IL-HPW was easily separated from the hydrolysates after reaction and was re-used five times without significant loss of activity. Overall findings reveal the potential of SBA-IL-HPW as a durable, environmentally benign catalyst for sugar production from renewable resources.
Purification and characterization of two novel β-galactosidases from Lactobacillus reuteri
Nguyen, Thu-Ha,Splechtna, Barbara,Steinboeck, Marlene,Kneifel, Wolfgang,Lettner, Hans Peter,Kulbe, Klaus D.,Haltrich, Dietmar
, p. 4989 - 4998 (2006)
The intracellular β-galactosidase (β-gal) enzymes from two strains of Lactobacillus reuteri, L103 and L461, were purified by ammonium sulfate fractionation, hydrophobic interaction, and affinity chromatography. Both enzymes are heterodimers with a molecular mass of 105 kDa, consisting of a 35 kDa subunit and a 72 kDa subunit. Active staining of L. reuteri L103 and L461 β-gal with 4-methylumbelliferyl β-D-galactoside showed that the intact enzymes as well as the larger subunits possess β-galactosidase activity. The isoelectric points of L. reuteri L461 and L103 β-gal were found to be in the range of 3.8-4.0 and 4.6-4.8, respectively. Both enzymes are most active in the pH range of 6-8; however, they are not stable at pH 8. The L. reuteri β-galactosidases are activated by various mono- and divalent cations, including Na+, K+, and Mn2+, and are moderately inhibited by their reaction products D-glucose and D-galactose. Because of their origin from beneficial and potentially probiotic lactobacilli, these enzymes could be of interest for the synthesis of prebiotic galactooligosaccharides.
Adxanthromycins A and B, new inhibitors of ICAM-1/LFA-1 mediated cell adhesion molecule from streptomyces sp. NA-148. II. Physico-chemical properties and structure elucidation
Takahashi, Senji,Nakano, Takayuki,Koiwa, Tsukasa,Noshita, Toshiro,Funayama, Shinji,Koshino, Hiroyuki,Nakagawa, Akira
, p. 163 - 170 (2000)
Adxanthromycins A and B are new inhibitors of ICAM-1/LFA-1 mediated cell adhesion molecule isolated from the fermentation broth of Streptomyces sp. NA-148. The molecular formula of adxanthromycins A and B were determined as C42H40O17 and C48H50O22, respectively by FAB-MS and NMR spectral analyses, and the structures of both compounds were elucidated to be a dimeric anthrone peroxide skeleton containing α-D-galactose by various NMR spectral analyses and chemical degradation.
Depsitinuside: A new depside galactoside from an endophytic fungus isolated from Viburnum tinus
Nazir, Mamona,Sultan, Misbah,Riaz, Naheed,Hafeez, Maria,Hussain, Hidayat,Ahmed, Ishtiaq,Schulz, Barbara,Draeger, Siegfried,Jabbar, Abdul,Krohn, Karsten,Ashraf, Muhammad,Saleem, Muhammad
, p. 1056 - 1060 (2011)
Chromatographic purification of the extract of an endophytic fungal culture yielded depsitinuside (1), a new phenolic ester together with ergosterol (2) and (22E,24S)-24-methyl-5-a-cholesta-7,22-diene-3b,5,6b-triol (3). The structure of 1 was elucidated based on 1D, 2D NMR spectroscopy and high-resolution mass spectrometry, whereas the known compounds (2 and 3) were identified by 1H NMR, mass spectrometry, and in comparison with the literature values. Compound 1 was evaluated for its enzyme inhibitory potential against acetylcholinesterase, butyrylcholinesterase and lipoxygenase, and was found inactive (10%-40% inhibition at a concentration of 2 mg/ml).
An unusual galactofuranose lipopolysaccharide that ensures the intracellular survival of toxin-producing bacteria in their fungal host
Leone, Maria R.,Lackner, Gerald,Silipo, Alba,Lanzetta, Rosa,Molinaro, Antonio,Hertweck, Christian
, p. 7476 - 7480 (2010)
Dress code for living in a fungus: Analysis of the carbohydrate coating of the toxin-producing endobacterium of the phytopathogenic fungus Rhizopus microsporus revealed an unprecedented lipopolysaccharide (LPS) structure, which is important for infection and colonization of the fungal host. A mutant lacking the unusual [→2)-β-D-galactofuranose-(1→]n O antigen (red in the schematic illustration) was incapable of forming a stable symbiosis with the fungus.
Polyphenols from Euphorbia pekinensis Inhibit AGEs Formation in Vitro and Vessel Dilation in Larval Zebrafish in Vivo
Lee, Ik-Soo,Jung, Seung-Hyun,Kim, Jin Sook
, p. 176 - 181 (2018)
To identify active compounds in the roots of Euphorbia pekinensis for treatment of diabetic complications, an active column fraction from a 70% EtOH extract of E. pekinensis root was purified by preparative reversed-phase high-performance liquid chromatography, leading to the isolation of a new ellagic acid derivative, 3,3′-di- O -methylellagic acid 4- O -(6- O -galloyl)- β -D-galactopyranoside (1), along with three known compounds, geraniin (2), 3,3′-di- O -methylellagic acid 4- O - β -D-xylopyranoside (3), and ellagic acid 3,3′-dimethyl ether (4). The structure of the new compound was established by extensive spectroscopic studies and chemical evidence. The inhibitory effects of isolated compounds 1 - 4 on advanced glycation end-products (AGEs) formation were examined. All compounds exhibited considerable inhibition of AGEs formation and IC 50 values of 0.41 - 12.33 μM, compared with those of the positive controls aminoguanidine (IC 50 = 1122.34 μM) and quercetin (IC 50 = 27.80 μM). In addition, the effects of 2 and 4 on the dilation of hyaloid-retinal vessels induced by high glucose (HG) in larval zebrafish were investigated; both compounds significantly reduced the HG-induced dilation of hyaloid-retinal vessels relative to the HG-treated control group.
Cyclotanoside, a New Cycloartane Glycoside from Flowers of Astragalus tanae
Alaniya,Kavtaradze, N. Sh.,Skhirtladze,Aneli
, p. 682 - 686 (2017)
The new cycloartane glycoside cyclotanoside and the triterpene saponin astragaloside VIII were isolated from flowers of Astragalus tanae Sosn. Their structures were established as 9β,19-cyclolanost-12,24E-dien-1α,3β,6α,16β,27-pentaol-27-O-β-D-(6′-O-acetoxy)-galactopyranoside and 3-O-α-L-rhamnopyranosyl-(1→2)-O-β-D-xylopyranosyl-(1→2)-O-β-D-glucuronopyranosyl-soyasapogenol B.
Structural and serological studies on the O-antigen show that Citrobacter youngae PCM 1505 must be classified to a new Citrobacter O-serogroup
Katzenellenbogen, Ewa,Kocharova, Nina A.,Gorska-Fraczek, Sabina,Gamian, Andrzej,Shashkov, Alexander S.,Knirel, Yuriy A.
, p. 52 - 55 (2012)
The O-polysaccharide obtained by mild acid hydrolysis of the lipopolysaccharide of Citrobacter youngae PCM 1505 was studied by sugar and methylation analyses along with 1D and 2D 1H and 13C NMR spectroscopies. The following structure of the tetrasaccharide repeating unit of the polysaccharide was established: Structural and serological data obtained earlier and in this work show that the strain studied is a candidate to a new Citrobacter O-serogroup.
