Showing papers on "Glucoside published in 2015"

Scopoletin and β-sitosterol glucoside from roots of Ipomoea digitata

Abstract: Plants are ancient source of medicine due to presence of bioactive molecules of various compounds in its different parts. Two compounds were isolated from ethanol extract of the roots of Ipomoea digitata. The compounds are Scopoletin (7-hydroxy-6-methoxycoumarin) and I²-sitosterol glucoside. The structures were elucidated by spectroscopic analysis (1H NMR & 13C NMR). Though the compounds are known natural products, scopoletin is the first report of its occurrence from the plant Ipomoea digitata. The compound scopoletin is very much important for its medicinal value.

Isobornyl acrylate: an impurity in alkyl glucosides

Abstract: Context: Alkyl glucosides and alkyl poly-glucosides are widely used as wetting agents, surfactants and emulsifiers in several industrial and cosmetic products. They are known as well-tolerated and are usually added to the primary surfactants in order to reduce the irritating potential of the main foaming agents.Objective: Recently, some authors suggested that allergic contact dermatitis to alkyl glucosides might be more frequent than suspected. On the other hand, the chemical structures of glucosides do not show potentially allergenic chemical groups or strongly polarized structures. The aim of our study is to investigate alkyl glucosides carrying out a detailed chemical analysis on samples of raw materials to identify potentially allergenic impurities or by-products contained in commercial samples of alkyl glucosides.Materials and methods: We chemically analyzed samples of cocoyl glucoside, decyl glucoside and lauryl glucoside by three different analytical methods, in order to identify any undesi...

Anti-Inflammatory Constituents from Bidens frondosa.

Abstract: A new polyacetylene glucoside (3E,5E,11E)-tridecatriene-7,9-diyne-1,2,13-triol-2-O-β-D-glucopyranoside (1), a new phenylpropanoid glucoside 2'-butoxyethylconiferin (2), and a new flavonoid glycoside 8,3',4'-trihydroxyflavone-7-O-(6''-O-p-coumaroyl)-β-D-glucopyranoside (3), have been isolated from Bidens frondosa together with fifty-three known compounds 4-56 The structures of these compounds were established by spectroscopic methods mainly ESIMS, 1D- and 2D-NMR spectroscopic data and comparison with literature data Compounds 1-34, 36, 39, 43, 47, 51, and 52 were tested for inhibition of nuclear factor kappa B (NF-κB) in 293-NF-κB-luciferase report cell line induced by lipopolysaccharide (LPS), and compounds 1, 2, 3, 9, 15, 21, 24 and 51 were tested for the production of TNF-α, IL-1β, IL-6, IL-10 in RAW 2647 macrophages induced by LPS In conclusion, the isolated compounds 1, 2, 3, 9, 15, 21, 24 and 51 exhibited significant activity in anti-inflammatory activity assays

Diversified glucosinolate metabolism: biosynthesis of hydrogen cyanide and of the hydroxynitrile glucoside alliarinoside in relation to sinigrin metabolism in Alliaria petiolata

Abstract: Alliaria petiolata (garlic mustard, Brassicaceae) contains the glucosinolate sinigrin as well as alliarinoside, a γ-hydroxynitrile glucoside structurally related to cyanogenic glucosides. Sinigrin may defend this plant against a broad range of enemies, while alliarinoside confers resistance to specialized (glucosinolate-adapted) herbivores. Hydroxynitrile glucosides and glucosinolates are two classes of specialized metabolites, which generally do not occur in the same plant species. Administration of [UL-(14)C]-methionine to excised leaves of A. petiolata showed that both alliarinoside and sinigrin were biosynthesized from methionine. The biosynthesis of alliarinoside was shown not to bifurcate from sinigrin biosynthesis at the oxime level in contrast to the general scheme for hydroxynitrile glucoside biosynthesis. Instead, the aglucon of alliarinoside was formed from metabolism of sinigrin in experiments with crude extracts, suggesting a possible biosynthetic pathway in intact cells. Hence, the alliarinoside pathway may represent a route to hydroxynitrile glucoside biosynthesis resulting from convergent evolution. Metabolite profiling by LC-MS showed no evidence of the presence of cyanogenic glucosides in A. petiolata. However, we detected hydrogen cyanide (HCN) release from sinigrin and added thiocyanate ion and benzyl thiocyanate in A. petiolata indicating an enzymatic pathway from glucosinolates via allyl thiocyanate and indole glucosinolate derived thiocyanate ion to HCN. Alliarinoside biosynthesis and HCN release from glucosinolate-derived metabolites expand the range of glucosinolate-related defenses and can be viewed as a third line of defense, with glucosinolates and thiocyanate forming protein being the first and second lines, respectively.

Species‐ and gender‐dependent differences in the glucuronidation of a flavonoid glucoside and its aglycone determined using expressed UGT enzymes and microsomes

Abstract: Flavonoids occur naturally as glucosides and aglycones. Their common phenolic hydroxyl groups may trigger extensive UDP-glucuronosyltransferase (UGT)- catalysed metabolism. Unlike aglycones, glucosides contain glucose moieties. However, the influence of these glucose moieties on glucuronidation of glucosides and aglycones remains unclear. In this study, the flavonoid glucoside tilianin and its aglycone acacetin were used as model compounds. The glucuronidation characteristics and enzyme kinetics of tilianin and acacetin were compared using human UGT isoforms, liver microsomes and intestinal microsomes obtained from different animal species. Tilianin and acacetin were metabolized into different glucuronides, with UGT1A8 produced as the main isoform. Assessment of enzyme kinetics in UGT1A8, human liver microsomes and human intestinal microsomes revealed that compared with tilianin, acacetin displayed lower Km (0.6-, 0.7- and 0.6-fold, respectively), higher Vmax (20-, 60- and 230-fold, respectively) and higher clearance (30-, 80- and 300-fold, respectively). Furthermore, glucuronidation of acacetin and tilianin showed significant species- and gender-dependent differences. In conclusion, glucuronidation of flavonoid aglycones is faster than that of glucosides in the intestine and the liver. Understanding the metabolism and species- and gender-dependent differences between glucosides and aglycones is crucial for the development of drugs from flavonoids.

Modification of emodin and aloe-emodin by glycosylation in engineered Escherihia coli

Abstract: Glycosyltransferase from Bacillus licheniformis DSM13 (YjiC) was used for enzymatic modification of emodin and aloe-emodin in vitro and in vivo. In order to increase the availability of UDP-glucose, three genes involved in the production of precursors of NDP-sugar in Escherichia coli BL21 (DE3) viz. d-glucose phosphate isomerase (pgi), d-glucose-6-phosphate dehydrogenase (zwf), and UDP-sugar hydrolase (ushA) were deleted and glucose-1-phosphate urididyltransferase (galU) gene was over expressed. To improve the yield of the products; substrate, time and media parameters were optimized, and the production was scaled up using a 3 L fermentor. The maximum yield of glycosylated products of emodin (emodin-O-β-d-glucoside) and aloe-emodin (aloe-emodin-O-β-d-glucoside) were approximately 144 µM (38 mg/L) and 168 µM (45 mg/L) respectively, representing almost 72 % and 84 % bioconversion of emodin and aloe-emodin when 200 µM of emodin and aloe-emodin were supplemented in the culture. Additionally, the emodin and aloe emodin major glycosylated products exhibited the highest stability at pH 8.0 and the stability of products was up to 70 °C and 60 °C respectively. Furthermore, the biological activities of emodin and its major glucoside (P1) were compared and their anti-cancer activities were assayed in several cancer cell lines. The results demonstrate that YjiC has the capacity to catalyze the glycosylation of these aromatic compounds and that glycosylation of anthraquinones enhances their aqueous solubility while retaining their biological activities.

Minutaside A, new α-amylase inhibitor flavonol glucoside from Tagetes minuta: Antidiabetic, antioxidant, and molecular modeling studies

Abstract: Investigation of the EtOAc fraction of Tagetes minuta L. (Asteraceae) aerial parts has afforded a new flavonol glucoside, minutaside A (quercetagetin 6-O-(6-O-hexanoyl)-β-D-glucopyranoside) (1), together with four known flavonoids: axillarin 7-O-β-D-glucopyranoside (2), quercetagetin 3,7-dimethoxy-6-O-β-D-glucopyranoside (3), quercetagetin 7-methoxy-6-O-β-D-glucopyranoside (4), and quercetagetin 6-O-β-D-glucopyranoside (5). Their structures were established by multiple spectroscopic methods in addition to HRESIMS (high-resolution electrospray ionisation mass spectra) and comparison with literature data. The antioxidant and anti-diabetic activities of the isolated flavonoids were evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and α-amylase inhibition assays. Compounds 1 and 5 showed significant antioxidant activity (84.1 and 83.0% at a 20 μM dose, respectively). Compounds 1, 4, and 5 exhibited strong α-amylase inhibitory activity compared with acarbose (a reference α-amylase inhibitor). However, 2 and 3 showed moderate activity. Molecular modeling studies of 1–5 that included docking, flexible alignment, and surface mapping were performed to evaluate their recognition profile α-amylase receptor. In docking simulations, 5 displayed a binding mode similar to that of acarbose in the active site of α-amylase enzyme.

Leucas aspera: medicinal plant review

Abstract: Plants is being used from more than 1000 years to treat diseases.The healing properties of plants has been transferred within the human communities for over the centuries. Leucas aspera commonly known as “Thumbai”, “Gumma” is found all over India.The Plant is used to treat many diseases such as cough,cold diarrhea,inflammatory diseases.The plants have been reported to have Anti-inflammatory, analgesic, anti-diarrheal, antimicrobial, antioxidant, and insecticidal activities.Bioactive components have been isolated such as Lignin,flavonoids, coumarins, steroids, terpenes, fatty acids, and aliphatic long-chain compounds.There are many other bioactive components identified on further studies mainly triterpenoids, oleanolic acid, ursolic acid and b-sitosterol, nicotine, sterols,glucoside, diterpenes, phenolic compounds (4-(24-hydroxy-1-oxo-5-n-propyltetracosanyl)-phenol).

Crotocascarins I–K: Crotofolane-Type Diterpenoids, Crotocascarin γ, Isocrotofolane Glucoside and Phenolic Glycoside from the Leaves of Croton cascarilloides

Abstract: From the 1-BuOH-soluble fraction of a methanol (MeOH) extract of the leaves of Croton cascarilloides, crotofolanes: crotocascarins I-K, nor-crotofolane: crotocascarin γ, isocrotofolane glucoside and phenolic glycoside were isolated by a combination of various separation techniques. Their structures were elucidated mainly from the NMR spectroscopic evidence. The structure of crotocascarin K was first elucidated by spectroscopic analysis and then was confirmed by X-ray crystallographic analysis. Its absolute structure was finally determined by the modified Mosher's method. Isocrotofolane glucoside was found to possess a new skeleton, however, its absolute structure remains to be determined.

Isolation and identification of bound compounds from corn bran and their antioxidant and angiotensin I-converting enzyme inhibitory activities

Abstract: A large amount of bound compounds, especially phenolics, present in corn bran has been underestimated because of difficulties in extracting them directly by organic solvents under mild conditions. Based on alkaline digestion, the bound compounds in corn bran were released and extracted with ethyl acetate. An investigation of the chemical constituents of the ethyl acetate (EtOAc) extract led to the isolation of ten compounds: trans-ferulic acid (1), trans-ferulic acid methyl ester (2), cis-ferulic acid (3), cis-ferulic acid methyl ester (4), vanillin (5), para-hydroxybenzaldehyde (6), 2-(1-oxo-2-hydroxyethyl) furan (7), graminones B (8), β-sitosterol glucoside (9), and sucrose (10). The chemical structures of these compounds were elucidated mainly by nuclear magnetic resonance and electrospray ionization mass spectrometry analysis. Graminones B was identified for the first time and showed potent angiotensin I-converting enzyme inhibitory activity, and compounds 1, 2, 3, and 4 displayed strong DPPH and ABTS+ radical-scavenging activity. This work represents the first recorded example of the isolation of compounds 3, 4, 8, and 9 from corn bran in the bound form.

Chemical constituents of Phragmanthera austroarabica A. G. Mill and J. A. Nyberg with potent antioxidant activity.

Abstract: Background: Phragmanthera austroarabica A.G. Mill. and J. A. Nyberg is a semi parasitic plant belonging to family Loranthaceae. It was collected from Saudi Arabia. It is widely used in folk medicine among the kingdom in treatment of various diseases including diabetes mellitus. Objective: The total alcoholic extract of P. austroarabica collected from Saudi Arabia was investigated for the chemical structure and prominent biological activity of the main constituents. Materials and Methods: Isolation of the active constituents was performed using different chromatographic techniques including column chromatography packed with silica or sephadex and preparative thin layer chromatography. The structures of the isolated compounds were established based on different spectroscopic data as mass spectrum, one-dimensional and two-dimensional nuclear magnetic resonance (correlation spectroscopy, heteronuclear single quantum coherence, and heteronuclear multiple-bond correlation). Results: Phytochemical investigation of the plant resulted in isolation of 12 compounds. The isolated compounds were identified as chrysophanic acid, emodin, chrysophanic acid-8- O -glucoside, emodin-8- O -glucoside, pectolinarigenin, quercetin, dillenetin-3- O- glucoside, catechin, catechin-4'- O -gallate, methyl gallate, lupeol and ursolic acid. All the isolated phenolic compounds revealed significant free radical scavenging activities when tested using 2,2-diphenyl-1-picrylhydrazyl reagent. Conclusion: The antioxidant activities of the isolated compounds can justify the use of P. austroarabica in traditional medicine for treatment of diabetes and verify its possible application as an antihyperglycemic drug.

Quercetin 7-O-glucoside suppresses nitrite-induced formation of dinitrosocatechins and their quinones in catechin/nitrite systems under stomach simulating conditions

Abstract: Foods of plant origin contain flavonoids. In the adzuki bean, (+)-catechin, quercetin 3-O-rutinoside (rutin), and quercetin 7-O-β-D-glucopyranoside (Q7G) are the major flavonoids. During mastication of foods prepared from the adzuki bean, the flavonoids are mixed with saliva and swallowed into the stomach. Here we investigated the interactions between Q7G and (+)-catechin at pH 2, which may proceed in the stomach after the ingestion of foods prepared from the adzuki bean. Q7G reacted with nitrous acid producing nitric oxide (˙NO) and a glucoside of 2-(3,4-dihydroxybenzoyl)-2,4,6-trihydroxy-3(2H)-benzofuranone. (+)-Catechin reacted with nitrous acid producing ˙NO and 6,8-dinitrosocatechin. The production of the dinitrosocatechin was partly suppressed by Q7G, and the suppression resulted in the enhancement of Q7G oxidation. 6,8-Dinitrosocatechin reacted further with nitrous acid generating the o-quinone, and the quinone formation was effectively suppressed by Q7G. In the flavonoids investigated, the suppressive effect decreased in the order Q7G ≈ quercetin > kaempferol > quercetin 4′-O-glucoside > rutin. Essentially the same results were obtained when (−)-epicatechin was used instead of (+)-catechin. The results indicate that nitrous acid-induced formation of 6,8-dinitrosocatechins and the o-quinones can be suppressed by flavonols in the stomach, and that both a hydroxyl group at C3 and ortho-hydroxyl groups in the B-ring are required for efficient suppression.

Herbicidal activity of constituents isolated from Solanum elaeagnifolium (Solanaceae)

Abstract: s: The bioactivity of chemical extracts from silverleaf nightshade Solanum elaeagnifolium Cav. seeds and leaves were tested for herbicidal activities, through water and ethanol extracts, against Portulaca oleracea L., Corchorus olitorius L., Convolvulus arvensis L. and Echinochloa crus-galli (L.) found in most Zea mays L. fields. Characterization of the isolated constituents from ethanol extract was conducted by various spectroscopic techniques. Purification of chloroform (100%) column fraction carried out by TLC plate using developing system; chloroform: ethanol: acetic acid (92:4:4) and hexane: chloroform: ethyl acetate (16:16:1) resulted chlorogenic acid, kaempferol and mangiferin. The second active column fraction eluted by chloroform: ethyl acetate was purified on TLC by chloroform: methanol: water (13:7:1) and butanol:water:formic acid (4:5:1) resulted in (coumaroyl glucoside, coumaroyl quince acid) and (kaempferol β-D-(6"-O-cis-cinnamoyl glucoside), dicaffeoyl quinic acids) respectively. The most active isolated component from S. elaeagnifolium seeds was chlorogenic acid which decreased P.oleracea total biomass fresh weight by (86.5%) followed by kaempferol β-D-(6"-O-cis-cinnamoyl glucoside) (84.4%), while a moderate effect was achieved from coumaroyl glucoside (79.37%), mangiferin (76.98), kaempferol (72.48%) and coumaroyl quince acid (66.47%); finally the lowest activity (63.6%) was achieved by dicaffeoyl quinic acids compared with the controls. Thus, the herbicidal activity of these constituents suggests their potential for development as natural herbicides.

Process for the enzymatic preparation of a product glucoside and of a co-product from an educt glucoside

Abstract: The invention relates to a process for the preparation of a product glucoside, preferably an oligosaccharide, in particular cellobiose, and of a co-product, preferably a monosaccharide, in particular fructose, from an educt glucoside, preferably from an oligosaccharide, in particular from sucrose, with enzymatic catalysis. The educt glucoside is thereby first cleaved enzymatically to glucose 1-phosphate and the co-product, and the glucose 1- phosphate is subsequently reacted to give the product glucoside. A reactant for the glucose 1-phosphate is preferably added, preferably a further saccharide, in particular glucose. The co-product formed in the cleavage of the educt glucoside, and the product glucoside formed in the reaction of the glucose 1-phosphate, are preferably each isolated.

Quantitative determination and identification of phenolic compounds of three Tunisian legumes: Vicia faba, Lens culinaris and Phaseolus vulgaris

Abstract: The polyphenol content and chromatographic profiles of three legumes extracts of Vicia faba L., Lens culinaris L . and Phaseolus vulgaris were found and compared . In addition, the total phenol content (TPC) in the cited legumes was measured by colorimetric method while the identification was carried out by chromatography LC-ESI-MS technique. The results of TPC, determined by the Folin-Ciocalteu reagent, had the maximum value in the acidified methanol legume extracts of P. vulgaris (3.201± 0.012 mg EAG/g), L. culinaris (2.591 ± 0.02 mg EAG/g) and V. faba (0.991 ± 0.01 mg EAG/g). Fragmentation behavior of polyphenol compounds were investigated using ion trap mass spectrometry in negative electrospray ionization. The MS, MS n of polyphenols allowed structural characterization of these compounds. Based on the obtained chromatograms, six phenolic compounds were identified in L. culinaris extract as catechin glucoside, catechin gallate, isomer 1 kaempferol tetraglycoside, isomer 2 kaempferol tetraglycoside, kaempferol-3-robinoside-7-rhamnoside and Kaempferol-3-glycoside. In P. vulgaris extract five compounds were identified: methyl catechin gallate, Myricetin-3-pentoside, Kaempferol 3-o-glycoside, Apigenin glycoside and Kaempferol hexose malic acid. Finally, V. faba extract contains also five compounds: catechin gallate, quercetin arabinoside, epicatechin glucoside, methyl epicatechin gallate and kaempferol glucoside sulfate.

Direct detection, cloning and characterization of a glucoside hydrolase from forest soil.

Abstract: A glucoside hydrolase gene, egl01, was cloned from the soil DNA of Changbai Mountain forest by homologous PCR amplification. The deduced sequence of 517 amino acids included a catalytic domain of glycoside hydrolase family 5 and was homologous to a putative cellulase from Bacillus licheniformis. The recombinant enzyme, Egl01, was maximally active at pH 5 and 50 °C and it was stable at pH 3–9, 4–50 °C, and also stable in the presence of metal ions, organic solvents, surfactants and salt. Its activity was above 120 % in 2–3 M NaCl/KCl and over 70 % was retained in 1–4 M NaCl/KCl for 6d. Egl01 hydrolyzed carboxymethyl cellulose, beechwood xylan, crop stalk, laminarin, filter paper, and avicel but not pNPG, indicating its broad substrate specificity. These properties make this recombinant enzyme a promising candidate for industrial applications.