Showing papers on "Glucoside published in 2017"

In vitro gastrointestinal digestion promotes the protective effect of blackberry extract against acrylamide-induced oxidative stress

Abstract: Acrylamide (AA)-induced toxicity has been associated with accumulation of excessive reactive oxygen species. The present study was therefore undertaken to investigate the protective effect of blackberry digests produced after (BBD) in vitro gastrointestinal (GI) digestion against AA-induced oxidative damage. The results indicated that the BBD (0.5 mg/mL) pretreatment significantly suppressed AA-induced intracellular ROS generation (56.6 ± 2.9% of AA treatment), mitochondrial membrane potential (MMP) decrease (297 ± 18% of AA treatment) and glutathione (GSH) depletion (307 ± 23% of AA treatment), thereby ameliorating cytotoxicity. Furthermore, LC/MS/MS analysis identified eight phenolic compounds with high contents in BBD, including ellagic acid, ellagic acid pentoside, ellagic acid glucuronoside, methyl-ellagic acid pentoside, methyl-ellagic acid glucuronoside, cyanidin glucoside, gallic acid and galloyl esters, as primary active compounds responsible for antioxidant action. Collectively, our study uncovered that the protective effect of blackberry was reserved after gastrointestinal digestion in combating exogenous pollutant-induced oxidative stress.

Cornusides A-O, Bioactive Iridoid Glucoside Dimers from the Fruit of Cornus officinalis.

Abstract: Fifteen new and rare iridoid glucoside dimers, cornusides A–O (1–15), and 10 known iridoid glucosides (16–25) were isolated from the fruit of Cornus officinalis. These new chemical structures were established through spectroscopic analysis (UV, IR, HRESIMS, 1D and 2D NMR). Compounds 1–25 were tested for their inhibitory activities by measuring IL-6-induced STAT3 promoter activity in HepG2 cells, and 3, 12, 17, 22, and 23 showed inhibitory effects, with IC50 values of 11.9, 12.2, 14.0, 7.0, and 6.9 μM, respectively.

Phenolics from Mikania micrantha and Their Antioxidant Activity

Abstract: A phytochemical study on the aerial parts of Mikania micrantha led to the isolation of two new phenolic compounds, benzyl 5-O-β-d-glucopyranosyl-2,5-dihydroxybenzoate (1) and (7S,8R)-threo-dihydroxydehydrodiconiferyl alcohol 9-acetate (2), together with twelve known compounds, benzyl 2-O-β-d-glucopyranosyl-2,6-dihydroxybenzoate (3), 4-allyl-2,6-dimethoxyphenol glucoside (4), (+)-isolariciresinol (5), icariol A2 (6), 9,10-dihydroxythymol (7), 8,9,10-trihydroxythymol (8), caffeic acid (9), p-coumaric acid (10), ethyl protocatechuate (11), procatechuic aldehyde (12), 4-hydroxybenzoic acid (13), and hydroquinone (14). Their structures were elucidated on the basis of extensive spectroscopic analysis. Except 8 and 9, all the other compounds were isolated from this plant species for the first time. The antioxidant activity of those isolated compounds were evaluated using three different assays. Compounds 1, 2, 3, 9, 10, 13, and 14 demonstrated significant 2,2′-azinobis-(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) free radical cation scavenging activity ranging from SC50 0.31 to 4.86 µM, which were more potent than l-ascorbic acid (SC50 = 10.48 µM). Compounds 5, 9, 11, and 12 exhibited more potent 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity (SC50 = 16.24–21.67 µM) than l-ascorbic acid (39.48 µM). Moreover, the ferric reducing antioxidant power (FRAP) of compounds 2, 5, 9, and 11 were discovered to be also comparable to or even more potent than l-ascorbic acid.

α-Glucosidase inhibitory and antioxidant activities of different Ipomoea aquatica cultivars and LC-MS/MS profiling of the active cultivar.

Abstract: The present study was designed to investigate the effect of Ipomoea aquatica extracted using water and methanol at various concentrations on the total phenolics, antioxidant capacity, and α-glucosidase inhibitory activities. Three I. aquatica cultivars were used in this study including the upland type with narrow leaves (K-11), low-land aquatic types with broader shaped leaves (K-25), and bamboo-shaped leaves (K-88). The results revealed that 70% methanol extract of K-11 showed higher total phenolic content and α-glucosidase inhibitory and antioxidant activities than the other two cultivars. The phytochemical constituents in the active extract K-11 were analyzed by means of liquid chromatography coupled with diode array detection and electrospray tandem mass spectroscopy. Eighteen compounds were detected of which 13 were tentatively identified as quercetin-3-O-sophoroside, quercetin-3-O-glucoside, quercetin-3,7-di-O-glucoside, nomilinic acid glucoside, 4,5-di-O-caffeoylquinic acid, 3,5-di-O-caffeoylquinic acid, luteolin-7-glucoside and 3,4,5-tricaffeolquinic acid, fatty acid together with quercetin, and tricaffeoylquinic acid derivatives. Practical Applications Antioxidants protect the human body against infections and degenerative diseases by inhibiting and scavenging free radicals. The present study showed that all methanol extracts of I. aquatica are rich in polyphenols in which 70% methanol extract showed highest in vitro antioxidant and α-glucosidase inhibitory activities. Knowledge about the antioxidant and α-glucosidase inhibitory activities of I. aquatica will promote its usage as a functional food, and it can be utilized as an antioxidant sources in food industry.

Functional Analysis of an Uridine Diphosphate Glycosyltransferase Involved in the Biosynthesis of Polyphenolic Glucoside in Tea Plants (Camellia sinensis).

Abstract: Polyphenols are one of the largest groups of compounds that confer benefits to the health of plants and humans. Flavonol glycosides are a major ingredient of polyphenols in Camellia sinensis. Flavonol-3-O-glycosides are characteristic astringent taste compounds in tea infusion. A polyphenolic glycosyltransferase (CsUGT72AM1) belonging to cluster IIIb was isolated from the tea plant. The full-length cDNA of CsUGT72AM1 is 1416 bp. It encodes 472 amino acids with a calculated molecular mass of 50.92 kDa and an isoelectric point of 5.21. The recombinant CsUGT72AM1 protein was expressed in Escherichia coli and exhibited catalytic activity toward multiple flavonoids and coniferyl aldehyde. The enzyme assay indicated that rCsUGT72AM1 could perform glycosidation of flavonols or coniferyl aldehyde in vitro to form 3-O-glucoside or 4-O-glucoside, respectively. Interestingly, this enzyme also had activities and performed multisite glycosidation toward flavanones. The consistent products were confirmed to be naringenin-7-O-glucoside and -4'-O-glucoside by the nuclear magnetism assay. In addition, in the enzyme assay with cyanidin as the substrate, the results suggested that the glycosylated activity of CsUGT72AM1 was remarkably inhibited by a high concentration of anthocyanins. The above results indicate that CsUGT72AM1 may be involved in the metabolism of flavonol, flavanone, anthocyanin, and lignin.

Transglycosylation of gallic acid by using Leuconostoc glucansucrase and its characterization as a functional cosmetic agent

Abstract: Gallic acid glycoside was enzymatically synthesized by using dextransucrase and sucrose from gallic acid. After purification by butanol partitioning and preparative HPLC, gallic acid glucoside was detected at m/z 355 (C13, H16, O10, Na)+ by matrix-assisted laser desorption ionization time-of-flight mass spectrometry. The yield of gallic acid glucoside was found to be 35.7% (114 mM) by response surface methodology using a reaction mixture of 319 mM gallic acid, 355 mM sucrose, and 930 mU/mL dextransucrase. The gallic acid glucoside obtained showed 31% higher anti-lipid peroxidation and stronger inhibition (Ki = 1.23 mM) against tyrosinase than that shown by gallic acid (Ki = 1.98 mM). In UVB-irradiated human fibroblast cells, gallic acid glucoside lowered matrix metalloproteinase-1 levels and increased the collagen content, which was indicative of a stronger anti-aging effect than that of gallic acid or arbutin. These results indicated that gallic acid glucoside is likely a superior cosmetic ingredient with skin-whitening and anti-aging functions.

Chemical Constituents of Nelumbo nucifera Seeds

Abstract: The phytochemical study for the extract of Nelumbo nucifera (Nymphaceae) seeds has led to the isolation of ten compounds including five simple phenolic compounds, two indole derivatives, a flavonoid glycoside, two abscisic acid derivatives. The interpretation of 1D and 2D NMR and ESI-Q-TOF-MS spectroscopic data revealed the chemical structures of isolates to be p-hydroxybenzoic acid (1), protocatechuic acid (2), (E)-p-coumaric acid (3), (E)-ferulic acid (4), (E)-sinapate-4-O-β-D-glucopyranoside (5), tryptophan (6), 3-indoleacetic acid (7), isoschaftoside (8), dihydrophaseic acid (9), dihydrophaseic acid 3''-O-β-D-glucopyranoside (10). To the best of our knowledge, 1 - 5 and 7 were identified for the first time from N. nucifera seeds, and the presence of dihydrophaseic acid (9) and its glucoside (10) were demonstrated secondly in this plant.

Bioengineering of the Plant Culture of Capsicum frutescens with Vanillin Synthase Gene for the Production of Vanillin.

Abstract: Production of vanillin by bioengineering has gained popularity due to consumer demand toward vanillin produced by biological systems. Natural vanillin from vanilla beans is very expensive to produce compared to its synthetic counterpart. Current bioengineering works mainly involve microbial biotechnology. Therefore, alternative means to the current approaches are constantly being explored. This work describes the use of vanillin synthase (VpVAN), to bioconvert ferulic acid to vanillin in a plant system. The VpVAN enzyme had been shown to directly convert ferulic acid and its glucoside into vanillin and its glucoside, respectively. As the ferulic acid precursor and vanillin were found to be the intermediates in the phenylpropanoid biosynthetic pathway of Capsicum species, this work serves as a proof-of-concept for vanillin production using Capsicum frutescens (C. frutescens or hot chili pepper). The cells of C. frutescens were genetically transformed with a codon optimized VpVAN gene via biolistics. Transformed explants were selected and regenerated into callus. Successful integration of the gene cassette into the plant genome was confirmed by polymerase chain reaction. High-performance liquid chromatography was used to quantify the phenolic compounds detected in the callus tissues. The vanillin content of transformed calli was 0.057% compared to 0.0003% in untransformed calli.

Optimization of Bioactive Polyphenols Extraction from Picea Mariana Bark

Abstract: Reported for its antioxidant, anti-inflammatory and non-toxicity properties, the hot water extract of Picea mariana bark was demonstrated to contain highly valuable bioactive polyphenols. In order to improve the recovery of these molecules, an optimization of the extraction was performed using water. Several extraction parameters were tested and extracts obtained analyzed both in terms of relative amounts of different phytochemical families and of individual molecules concentrations. As a result, low temperature (80 °C) and low ratio of bark/water (50 mg/mL) were determined to be the best parameters for an efficient polyphenol extraction and that especially for low molecular mass polyphenols. These were identified as stilbene monomers and derivatives, mainly stilbene glucoside isorhapontin (up to 12.0% of the dry extract), astringin (up to 4.6%), resveratrol (up to 0.3%), isorhapontigenin (up to 3.7%) and resveratrol glucoside piceid (up to 3.1%) which is here reported for the first time for Picea mariana. New stilbene derivatives, piceasides O and P were also characterized herein as new isorhapontin dimers. This study provides novel information about the optimal extraction of polyphenols from black spruce bark, especially for highly bioactive stilbenes including the trans-resveratrol.

Synthesis and Functional Characterization of Caffeic Acid Glucoside Using Leuconostoc mesenteroides Dextransucrase

Abstract: Caffeic acid was modified via transglucosylation using sucrose and dextransucrase from Leuconostoc mesenteroides B-512FMCM. Following enzymatic modification, a caffeic acid glucoside was isolated by butanol separation, silica gel chromatography, and preparative HPLC. The synthesized caffeic acid glucoside had a molecular mass-to-charge ratio of 365 m/z, and its structure was identified as caffeic acid-3-O-α-d-glucopyranoside. The production of this caffeic acid-3-O-α-d-glucopyranoside at a concentration of 153 mM was optimized using 325 mM caffeic acid, 355 mM sucrose, and 650 mU mL–1 dextransucrase in the synthesis reaction. In comparison with the caffeic acid, the caffeic acid-3-O-α-d-glucopyranoside displayed 3-fold higher water solubility, 1.66-fold higher antilipid peroxidation effect, 15% stronger inhibition of colon cancer cell growth, and 11.5-fold higher browning resistance. These results indicate that this caffeic acid-3-O-α-d-glucopyranoside may be a suitable functional component of food and ph...

Production of Cinnamyl Alcohol Glucoside from Glucose in Escherichia coli

Abstract: Rosin, a cinnamyl alcohol glucoside, is one of the important ingredients in Rhodiola rosea, which is a valuable medicinal herb used for centuries. Rosin displayed multiple biological activities. The traditional method for producing rosin and derivatives is direct extraction from R. rosea, which suffers from limited availability of natural resources and complicated purification procedure. This work achieved de novo biosynthesis of rosin in Escherichia coli. First, a biosynthetic pathway of aglycon cinnamyl alcohol from phenylalanine was constructed. Subsequently, the UGT genes from Rhodiola sachalinensis (UGT73B6) or Arabidopsis thaliana (UGT73C5) were introduced into the above recombinant E. coli strain to produce rosin. Then the phenylalanine metabolic pathway of E. coli was optimized by genetic manipulation, and the production of rosin by the engineered E. coli reached 258.5 ± 8.8 mg/L. This study lays a significant foundation for microbial production of rosin and its derivatives using glucose as the re...

Synthesis of Cinnamyl and Caffeoyl Derivatives of Cucurbitacin-Eglycoside Isolated from Citrullus colocynthis Fruits and their Structures Antioxidant and Anti-inflammatory Activities Relationship.

Abstract: Background Citrullus colocynthis (L.) Schrad is an important medicinal plant belonging to the family Cucurbitaceae. Cucurbitacin E glucoside (1) was isolated from Citrullus colocynthis fruits. A novel mono-ester of cucurbitacin-E and cinnamyl and caffeoyl-β-D-glucoside (2 and 3) was synthesized by reaction of cucurbitacin E glucoside with cinnamic and/or caffeic acid in the presence of CHCl2 and K2CO3 with constant stirring with an ice-cooling state for 24h. Mass analyses of the isolated and purified compounds were determined. Methods The elemental analysis (C, H, N) suggesting the molecular formulae of the compounds (1-3) to be C38H54O13, C47H60O14, and C47H60O16; respectively. I.R., 1H-NMR, and 13C-NMR analyses were recorded. The median lethal doses (LD50s) of compounds (1-3) in rats were 1262.5, 2500 and 2350 mg/kg b.w., respectively. The anti-inflammatory, total antioxidant, reducing power, anti-reactive oxygen species (ROS) and anti-reactive nitrogen species (RNS) were more pronounced in compound 3 compared to compounds (1-2). This study provides the scientific basis for the anti-inflammatory effects of the isolated cucurbitacin E glucoside (1) and its derivatives (2 and 3) in a t-BHP (tert-butyl hydrogen peroxide)-induced liver damage model. Results Injection of rats with t-BHP (1.8 mmol/kg) showed a significant increase in plasma alanine transaminases (ALT), aspartate transaminases (AST), alkaline phosphatase (ALP), lactate dehydrogenase (LDH) and malondialdehyde (MDA) as well as hepatic tumor Necrosis Factor-α (TNF-α), interleukin- 6 (IL-6) and interleukin-23 (IL-23) when compared with control group. Also, injection of rats with t-BHP showed a significant increase in a liver level of reduced glutathione (GSH), superoxide dismutase (SOD), catalase (CAT) and glutathione-S-transferase (GST) as compared with control group. Oral administration of cucurbitacin E glucoside (1) and its derivatives (2 and 3) at a concentration of 25 and 50 mg/kg b.wt daily for 5 days showed a significant protection against-induced alteration in liver GSH, SOD, CAT and GST as well as plasma ALT, AST, ALP, LDH and MDA levels. Furthermore, Cucurbitacin E glucoside (1) and its derivatives (2 and 3) inhibited the elevation of proinflammatory cytokines (TNF-α, IL-6, and IL-23) in the livers of t-BHP-treated rat models. Conclusion These results suggested that mechanistic-based evidence substantiating the traditional claims of cucurbitacin E glucoside (1) and its derivatives (2 and 3) to be applied for the treatment of inflammation-related disorders, such as oxidative liver damage and inflammation diseases.

Chemical constituents, radical scavenging activity and enzyme inhibitory capacity of fruits from Cotoneaster pannosus Franch.

Abstract: Cotoneaster pannosus (Rosaceae) is a semievergreen shrub, producing globose dark red pomes, native to China and widely used as an ornamental plant all over the world. Despite its extensive cultivation, little information is available on the chemical composition and biological activities of its fruits. In this work, the analysis of the chemical composition of C. pannosus fruits, in terms of phenolic components, carotenoids and ascorbic acid by HPLC/DAD, HPLC/ESI-MS and MS/MS as well as in terms of macro- and micro-nutrients was performed. The fruits proved to be a good source of shikimic acid and caffeoylquinic acids, whereas β-carotene, pelargonidin-3-O glucoside and cyanidin-3,5-rutinoside gave an important contribution to the color of the fruit. Both the polar and apolar fruit extracts showed noteworthy radical scavenger activity and inhibitory effects against monoamine oxidase A (MAO-A), tyrosinase (TYR) and α-glucosidase, making C. pannosus red pomes a promising candidate ingredient in functional foods and dietary supplements.