Acetyl Glucosides Research Articles

Antioxidant and phytoestrogenic activities of puffed black soybeans (Glycine max)

Abstract Black soybeans are generally consumed after steaming, boiling or roasting. They have also been consumed after puffing, which is a thermal processing using high temperature and high pressure. However, limited information is available on bioactive constituents of puffed black soybeans. Therefore, antioxidant and phytoestrogenic activities of puffed black soybeans were investigated. The puffing pressures used were 490, 588, 686, and 784 kPa. Raw and autoclaved samples were designated as “raw” and “control”, respectively. In case of isoflavones, decarboxylation and demalonylation of malonylglucoside isoflavone, deacetylation of acetyl glucoside isoflavone as well as deglycosylation of glucoside isoflavone were occurred by puffing and autoclaving resulting in transformation of malonylglucoside isoflavones to acetylglucoside and glucoside isoflavones. Glycitein was only detected after puffing over 490 kPa, and acetylglycitin and acetyldaidzin were detected after puffing. Antioxidant activities, total reducing capacity, total flavonoid contents, and browning increased with increasing puffing pressure with some exception (decreased TFC and browning at 784 kPa). Anthocyanins were degraded into phenolic acids by puffing. Consequently, puffing is an efficient process for conversion of specific phytoestrogenic compounds, such as glycitein, and novel processing for improvement of antioxidant activity of black soybeans.

Antimicrobial Potential of Silver Nanoparticles Synthesized Using Medicinal Herb Coptidis rhizome.

The phenolic compounds (PC) of soybeans (Glycine max (L.) Merrill) varies mainly based on factors like genetics, the environment, and also the food processing techniques used. The effect of storage time and temperature on the phenolic acids and isoflavones composition of raw soybean flour (RWSF) and roasted soybean flour (RSF) were analyzed using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Based on the analysis results, 56 PC and free amino acids were detected in the RWSF and RSF. The total phenolic content (TPC) was 301.59 µg/g in the control RWSF and 257.47 µg/g in the control RSF. In the analysis, eight types of phenolic acids and one flavonoid group belonging to the isoflavone group were detected. When comparing storage conditions of RWSF, 24 and 48 weeks of storage showed higher concentration of phenolic acids. In RSF, the percentage of total acetyl glucosides was high, but the outcome was reversed after 2 weeks. This study had identified that the composition of PC in RWSF and RSF were affected when the storage temperature increased and the storage time lengthened.

Evaluation of phytochemical content, antioxidant, antimicrobial activity and DNA cleavage effect of endemic Linaria corifolia Desf. (Plantaginaceae)

AbstractThe aim of this study is to isolate Linaria corifolia Desf. (Plantaginaceae) and identify a new apigenine derivatives 6,3’-dimethoxyapigenin-7-O-[(rhamnosyl)-(1-2)-6’’-acetyl glucoside]. Moreover, we analysed biological activity and flavonoids by using HPLC methods from extracts. The Linaria corifolia Desf. samples were collected in Black Sea Region of Turkey. Ethanol (EtOH), ethyl acetate (EtOAc) and dichloromethane (DCM) extracts in aerial and undersolid parts of plant were evaluated for antioxidant, antimicrobial activity and effect of DNA cleavage. Quercetin, gallic acid and catechin as flavonoids were identified in EtOH, EtOAc, DCM extracts.

A Sensitive LC-MS Method for Anthocyanins and Comparison of Byproducts and Equivalent Wine Content

Anthocyanins are a group of phenolic compounds with great importance, not only because they play a crucial role in a wine’s quality, but also due to the fact that they can have beneficial effects on human health. In this work, a method was developed for the detection and identification of these compounds in solid wastes of the wine-making industry (red grape skins and pomace), using liquid-liquid extraction (LLE) prior to the liquid chromatography-mass spectrometry technique (LC-MS). The complete process was investigated and optimized, starting from the extraction conditions (extraction solution selection, dried matter-to-solvent volume ratio, water bath extraction duration, and necessary consecutive extraction rounds) and continuing to the mobile phase selection. The extraction solution chosen was a methanol/phosphoric acid solution (95/5, v/v), while three rounds of consecutive extraction were necessary in order to extract the maximum amount of anthocyanins from the byproducts. During the LC-MS analysis, acetonitrile was selected as the organic solvent since, compared with methanol, not only did it exhibit increased elution strength, but it also produced significantly narrower peaks. To enable accurate identification of the analytes and optimization of the developed method, kuromanin chloride and myrtillin chloride were used as standards. Furthermore, the wine variety (Syrah) from which the specific byproducts were produced was analyzed for its anthocyanin content, leading to interesting conclusions about which anthocyanins are transferred from grapes to wine during the vinification procedure, and to what extent. The results of this study showed that the total concentration of anthocyanins estimated in wine byproducts exceeded almost 12 times the equivalent concentration in Syrah wine, while the four categories of detected anthocyanins, simple glucosides, acetyl glucosides, cinnamoyl glucosides, and pyroanthocyanins, were present in different ratios among the two samples, ranging from 18.20 to 1, to 5.83 to 1. These results not only confirmed the potential value of these byproducts, but also indicated the complexity of the anthocyanins’ transfer mechanism between a wine and its byproducts.

Changes in the Relationship Between Temperature During the Seed‐Filling Period and Soya Bean Seed Isoflavones Under Water‐Deficit Conditions

AbstractIsoflavones have been shown to have health‐promoting activities in humans and are particularly abundant in soya bean. This study was conducted to determine how water deficit during seed fill affects the already known relationship between temperature and, alternately, solar radiation with soya bean seed isoflavone content. Isoflavone profile was analysed from seed samples of commercial cultivars grown in 76 environments in Argentina (29–38°S). Significant explanatory multiple linear regressions were detected for total isoflavones (TI), aglycones (AGL), glucosides (GLC), malonyl glucosides (MAL) and acetyl glucosides (ACE) regarding the following: temperature during seed fill (TmR5R7) and precipitation minus potential evapotranspiration during the reproductive period (pp‐PETR1R7), as well as for the combinations of these climatic variables. Cumulative solar radiation predicted isoflavone content but was less robust than TmR5R7 and pp‐PETR1R7. To our knowledge, this is the first report of changes in the relationship between TI, as well as AGL, GLC, MAL, and ACE and TmR5R7 as a function of drought in the field. When pp‐PETR1R7 was below 70 mm (indicating drought), TI, as well as AGL, GLC, MAL, and ACE decreased linearly with rising temperatures and with increasing water deficit (decreasing values of pp‐PETR1R7), with both climatic variables exhibiting additive effects on isoflavones. Our results also suggest that water deficit (estimated by pp‐PETR1R7) would be important for modelling the relationship between temperature and soya bean seed isoflavones in rainfed crops.

Isoflavone Retention during Processing, Bioaccessibility, and Transport by Caco-2 Cells: Effects of Source and Amount of Fat in a Soy Soft Pretzel

The impact of source and amount of lipid used to prepare a soy soft pretzel on the bioaccessibility and transport of isoflavones was investigated using the coupled in vitro digestion/Caco-2 human cell model. Pretzels were prepared without or with 2.9 or 6.0% exogenous lipid from either shortening, canola oil, ground almond, or ground hazelnut. The isoflavone backbone structure was stable during pretzel production, although there was partial conversion from malonyl and acetyl glucosides to simple glucosides and aglycones. Endogenous β-glucosidase activity in ground almond facilitated partial conversion of simple glucosides to aglycones during proofing, resulting in a slight decrease in bioaccessibility of isoflavones as compared with other sources of lipid. Amount and source of lipid did not affect bioaccessibility or uptake and metabolism of isoflavones by Caco-2 cells, although transport across the monolayer was greater with the lesser amount of shortening. These results suggest that the isoflavone structure, but not source or amount of lipid in a soy pretzel, may affect bioavailability of isoflavones.

Composition and stability of phytochemicals in five varieties of black soybeans ( Glycine max)

Abstract Phytochemical compositions of five varieties of black soybeans (Glycine max) and their stabilities at room temperature, 4 and −80 °C over 14 months were determined by HPLC systems with electrochemical (ECD) and UV detectors. Polyphenol profiling was carried out by a liquid chromatography–electrospray ionisation-mass spectrometry (LC–ESI-MS) with orbitrap as a mass analyser in both positive and negative ion modes, and polyphenols in aglycone forms were quantified by HPLC–ECD. Five different varieties of black soybeans (G. max) contained 249–405 μg/g dry wt of γ-tocopherol and 6.76–14.98 μg/g dry wt of lutein. Major polyphenols in black soybeans (G. max) were daidzein (193–288 μg/g dry wt) and genistein (145–223 μg/g dry wt), mainly present as glucosides and acetyl glucosides. No significant decrease was found in total phenols of black soybeans (G. max) stored at room temperature, 4 or −80 °C for 14 months. On the other hand, lutein and γ-tocopherol degraded significantly within a month of storage at room temperature (p

Stability of Isoflavone Isomers in Steamed Black Soybeans and Black Soybean Koji Stored under Different Conditions

Steamed black soybeans and black soybean koji, a potentially functional food additive, were stored at 4 or 25 degrees C with or without deoxidant and desiccant for 120 days. After storage, steamed black soybeans and koji showed various extents of reduction in isoflavone contents dependent on storage temperature, packaging condition, and the kind of isoflavone isomer. Generally, black soybeans and koji showed the highest residual of isoflavone when they were stored at 4 degrees C with deoxidant and desiccant. Under this storage condition, beta-glucosides (daidzin, glycitin, and genistein), acetyl glucosides (acetyldaidzin, acetylglycitin, and acetylgenistin), manlonyl glucosides (malonyldaidzin, malonglycitin, and malonylgenistin), and aglycones (daidzein, glycitein, and genistin) in steamed black soybeans exhibited residuals of 100.1-100.9, 92.0-99.4, 90.0-94.0, and 77.2-78.8%, respectively, of their original contents after 120 days of storage. Meanwhile, the residuals found in black soybean koji were 77.8-90.0, 13.1-88.9, 66.7-85.5, and 76.4-80.6%, respectively.

Evolution of red wine anthocyanins during malolactic fermentation, postfermentative treatments and ageing with lees

A comparative study was conducted on nine batches of wine, from the same initial wine, subjected to malolactic fermentation and ageing in barrels, under different technological conditions: Malolactic fermentation in barrel or in tank, with or without wine clarification, ageing with or without lees and stirring or no stirring of the lees. Samples were taken of the initial wine, of the wine at the end of malolactic fermentation, of the wines after clarifying treatments, and after 3, 6, 9, 12 and 14 months of ageing in the barrel, making a total of 48 wines. As a result of the anthocyanin analysis of all the wines studied, a total of 21 different anthocyanin compounds were detected, which can be classified into four groups: simple glucosides, acetyl glucosides, cinnamoyl glucosides and pyroanthocyanins. During MLF, it was shown that the effect of the container used seems to be more important than the metabolic activity of the bacteria responsible for the process. From application of the LSD test, significant differences were found in the concentrations of all the anthocyanin compounds identified due to ageing time and significant differences were also revealed for most anthocyanin compounds in relation to the manufacturing method, especially the presence or absence of lees.

HPLC-DAD–MS Analysis of Anthocyanins in Rose Wine Made From cv. Öküzgözü Grapes, and Effect of Maceration Time on Anthocyanin Content

The anthocyanin composition of rose wine made from cv. Okuzgozu, a variety of grape native to Turkey, and the effect of maceration time (3, 6, 12, 18, or 24 h) on the anthocyanin content of the wine have been investigated. High-performance liquid chromatography with diode-array detection (HPLC-DAD) and mass spectrometry (MS) were used for anthocyanin analysis. Thirteen different anthocyanins, including five glucosides, five acetyl glucosides, and three coumaroyl glucosides were identified and quantified. It was found that an important characteristic of Okuzgozu rose wine was the presence of a large amount of malvidin-3-glucoside and its acylated esters. The total anthocyanin content of the wine increased with increasing maceration time. On the basis of sensory analysis, the most preferred wine was that produced with 3-h maceration, because of its better color and general flavor attributes.

Quantitative determination of acetyl glucoside isoflavones and their metabolites in human urine using combined liquid chromatography–mass spectrometry

To investigate whether the bioavailability of isoflavones could be an alternative to fermented soy foods, the conjugated forms of soy nutritional supplement (containing 98% acetyl glucoside isoflavones) were consumed by eight human volunteers (three were Asian people and five were British). Their daily urine samples were collected before and after a 5-week consumption of supplementation period. Conjugated isoflavones of genistein, daidzein and glycitein were hydrolyzed by enzyme, extracted with methyl tert-butyl ether and analysed using liquid chromatography coupled with electrospray tandem mass spectrometry. Daidzein, genistein, glycitein, dihydrogenistein, dihydrodaidzein and O-desmethylangolensin were identified and quantified simultaneously with high recoveries. The levels of free isoflavones and total isoflavones were compared, and isoflavone glucuronides were identified much higher than the corresponding sulfates or aglycone isoflavones. This method provided the measurement of isoflavones with high sensitivity and specificity and simplified the sample pre-treatment procedure. The limitation of detections of dihydrodaidzein, 3'-hydroxydaidzein, glycitein, daidzein, genistein, dihydrogenistein and O-desmethylangolensin were 37, 23.5, 12.2, 15.4, 14.8, 2.20 and 0.31 pmol, respectively. Only 0.5 ml of urine sample was needed.

Evaluation of Soyasaponin, Isoflavone, Protein, Lipid, and Free Sugar Accumulation in Developing Soybean Seeds

A combination of analytical techniques was used to examine and quantify seed compositional components such as protein, lipid, free sugars, isoflavones, and soyasaponins during soybean development and maturation in two Korean soybean cultivars. Protein accumulation was rapid during reproductive stages, while lipid content was only relatively moderately increased. The major carbohydrate saccarides sucrose and stachyose constantly increased during the reproductive stage. Previously published results suggest that the free sugar and lipid content reached their maximal concentrations at a relatively early stage of seed development and remain constant in comparison to other chemical components. The malonylglucosides were the predominant isoflavone form followed by the glucosides, acetyl glucosides, and aglycone forms. As soybean seed matures, total soyasaponin concentration was constantly decreased until the R8 stage. Soyasaponin beta(g) was the major soyasaponin in DDMP-conjugated group B soyasaponins, followed by the non-DDMP counterpart soyasaponin I and soyasaponin A1. The ratio of total isoflavone to total soyasaponin in the developing soybean increased from 0.06 to 1.31. Protein, lipid, and free sugar contents in the developing soybean seeds showed significant positive correlations with conjugated isoflavones and total isoflavone concentration, while the lipid contents showed a negative correlation with the isoflavone aglycone. Protein, lipid, and free sugar contents showed a negative correlation with total group A and B soyasaponins and total soyasaponins; however, only the soyasaponin A content was significantly negatively correlated with free sugar content. Total soyasaponin content was negatively correlated with isoflavone content (r = -0.828 at p < 0.01).

Red Clover Trifolium pratense L. Phytoestrogens: UV-B Radiation Increases Isoflavone Yield, and Postharvest Drying Methods Change the Glucoside Conjugate Profiles

Isoflavone extracts of red clover Trifolium pratense L. (cv. Pawera) with dissimilar glucoside conjugate profiles were obtained by employing different postharvest drying methods. The most prominent isoflavones found were formononetin and biochanin A and their corresponding glucosides and malonyl glucoside esters. Postharvest freeze drying inhibited the conversion of the glycosides to the aglycones, while vacuum drying allowed for maximum conversion of the glycosides to their corresponding aglycones. Air drying produced a low level of the aglycones formononetin and biochanin A, and oven drying promoted decarboxylation of the malonyl glucosides to the acetyl glucosides. Exposure to enhanced UV-B radiation resulted in an increase in total formononetin and biochanin A isoflavone levels, indicating that harvest during a period of high ambient UV-B radiation may be appropriate for maximum yield. The levels of caffeic acid and flavonols also increased by about 40 and 250%, respectively, on exposure to enhanced UV-B radiation.

Stability of isoflavones during extrusion processing of corn/soy mixture.

The influence of extrusion processing in the presence of corn on the quantity and quality of genistein, daidzein, and their respective beta-glucoside, acetyl glucoside, and malonyl glucoside derivatives was evaluated. Products of 100% soy (textured) and a blend of 20% soy protein concentrate (SPC) and 80% corn meal (direct-expanded) were extruded, with evaluations before and after extrusion. In addition, a 3 x (3 x 3) split-plot factorial experiment investigated the influence of barrel temperature (110, 130, 150 degrees C), moisture content (22, 24, 26%), and relative residence time (1, 0.8, 0.6) on extruder response and isoflavone profile. The extrusion barrel temperature had the most influence on isoflavone profile, especially decarboxylation of the malonyl beta-glucoside, followed by the moisture content. The amount of extractable isoflavones decreased after extrusion for both the SPC and SPC/corn meal blend when extracted with 80% aqueous methanol but remained approximately the same when first hydrated with water before extraction. However, initially hydrating with water produced enzymatic glycolysis in the unextruded samples, increasing the aglycons dramatically.

Convenient Synthesis of Monoselenoacetals from Acetals with Phenyl Trimethylsilyl Selenide

Monoselenoacetals can be efficiently prepared from acetals by treatment with phenyl trimethylsilyl selenide in the presence of a catalytic amount of trimethylsilyl trifluoromethanesulfonate. This procedure also effects the transformation of acetyl glucoside into selenoglucoside.

Chemical studies on Viburnum awabuki K. Koch.

From Viburnum awabuki K. KOCH (Caprifoliaceae), four new acetyl glucosides of scopoletin, 2'6'-di-o-acetylscopolin (1), 3', 6'-di-O-acetylscopolin (2), 6'-O-acetylscopolin (3) and 2'-O-acetylscopolin (4), and two lupane-type triterpenes, 6α-hydroxylup-20(29)-en-3-on-28-oic acid (6) and its 6β-epimer (7), were isolated. Their structures were elucidated on the basis of physicochemical evidence, including proton and carbon-13 nuclear magnetic resonance spectrometry.

Isolation of a new isoflavone acetyl glucoside, 6"-O-acetyl genistin, from soybeans.

Isolation of a new isoflavone acetyl glucoside, 6"-O-acetyl genistin, from soybeans.

Studies on terpene glycosides. II. Gas chromatographic optical resolution of dl-menthol and dl-borneol via its acetyl glucoside derivatives.

Studies on terpene glycosides. II. Gas chromatographic optical resolution of dl-menthol and dl-borneol via its acetyl glucoside derivatives.