Types Of Glucosides Research Articles

CONTROL OF THE SELECTIVITY OF THE SEPARATION OF GRAPE ANTHOCYANIDIN 3-GLUCOSIDES AND 3,5-DIGLUCOSIDES: DETERMINATION OF ANTHOCYANINS IN GRAPE FRUIT GROWN IN THE BELGOROD REGION

For the first time, a new version of the separation of 3-glucosides and 3,5-diglucosides of the five main anthocyanidins for grape fruits - delphinidin, cyanidin, petunidin, peonidin and malvidin under reverse-phase HPLC conditions was proposed. It has been shown that the replacement of the traditionally used acetonitrile with environmentally more acceptable ethanol upon acidification with ortho-phosphoric rather than formic acid makes it possible to significantly change the selectivity of the separation of two types of glucosides at their joint presence. The proposed separation option allows differentiating between Vitis vinifera grapes, in the fruit peel of which only 3-glucosides of the above anthocyanidins are synthesized, and grapes of other species or hybrid grape varieties. For a complete review of the anthocyanin composition, it is necessary to use a gradient mode, since the acylation of anthocyanins with acetic and p-coumaric acids significantly changes the lipophilicity of anthocyanins. The type of anthocyanins was analyzed according to the previously proposed system, which takes into account the activity of three types of enzymes: 1) 5-О-glucosyltransferase that leads to 3,5-diglucosides synthesis; 2) 3',5'-hydroxylase responsible for ring B hydroxylation; 3) anthocyanin O-methyltransferase for converting cyanidin into peonidin derivatives as well as delphinidine into petunidin and malvidin glycosides. The method was used to determine anthocyanins in 43 grape varieties grown in Belgorod on farms and private farms. Among the studied grapes, varieties were found with grape fruits with the accumulation of only 3-glucosides, as well as 3-glucosides and 3,5-diglucosides simultaneously, with delphinidin and cyanidin types of anthocyanins, and with different degrees of methylation. The calculated parameters for all grape varieties are presented in two tables and a brief discussion of some varieties is given.

Antifungal Activities of Cassia angustifolia Leaf Ethanolic Extract against Various Candida Spp.

Indian senna (Cassia angustifolia) is a perennial shrub belonging to the family Fabaceae. Indian senna contains flavonoids, pinnitolos (polyols), acidic polysaccharides, and mineral substances. It also contains two types of glucosides known as sennosides A and B and other compounds, including myricyl alcohol, anthraquinone derivatives, galactose, arabinose, rhamnose, galacturonic acid, chrysophanic acid, salicylic acid, resin, and mannitol. The antifungal activity of the extract was assessed against fungal strains, including Candida albicans (ATCC10231), Candida parapsilosis, and Candida auris. The result showed that the leaf extract of Cassia angustofolia exhibits significant antifungal activity against all tested fungal strains. After the result, Indian Senna which could be used to develop new drugs for the treatment of resistant fungal infections. Further research and optimum preservation, and flavonoids extraction methods is needed, particularly in the developing world, where senna leaf and flower harvest processing methods are more traditional.

An automated method to evaluate the enzyme kinetics of β-glucosidases.

Enzyme kinetic measurements are important for the characterization and engineering of biocatalysts, with applications in a wide range of research fields. The measurement of initial reaction velocity is usually slow and laborious, which motivated us to explore the possibilities for automating this process. Our model enzyme is the maize β-glucosidase Zm-p60.1. Zm-p60.1 plays a significant role in plant growth and development by regulating levels of the active plant hormone cytokinin. Zm-p60.1 belongs to a wide group of hydrolytic enzymes. Members of this group hydrolyze several different types of glucosides, releasing glucose as a secondary product. Enzyme kinetic measurements using artificial substrates are well established, but burdensome and time-consuming. Thus, they are a suitable target for process automation. Simple optical methods for enzyme kinetic measurements using natural substrates are often impossible given the optical properties of the enzymatic reaction products. However, we have developed an automated method based on glucose detection, as glucose is released from all substrates of glucosidase reactions. The presented method can obtain 24 data points from up to 15 substrate concentrations to precisely describe the enzyme kinetics. The combination of an automated liquid handling process with assays that have been optimized for measuring the initial hydrolysis velocity of β-glucosidases yields two distinct methods that are faster, cheaper, and more accurate than the established protocols.

Action analgésique de différents extraits non-volatils de Nepeta atlantica Ball et Nepeta tuberosa L. ssp. reticulata (Desf.) Maire

Analgesic Activity of Differents Nonvolatils Extracts of Nepeta atlantica Ball and Nepeta Tuberosa L. ssp. Reticulata (Desf.) MaireDifferent extracts of Nepeta atlantica Ball and Nepeta tuberosa L. ssp. reticulata (Desf.) Maire contain mainly a secondary metabolites with iridoïd lactonic and glucosidic type, also with triterpine lupan type.The aerial part of each species is crushed, then extracted in methanol by cold maceration, called global extracts. The global extracts will be extracted trough various solvents: initially by hexan then by the dichloromethan after that by the ethyl acetate and at the end by the buthanol. Each one of obtained extracts will be used for the following trials: i) Tail flick trial on the rat for the central morphine like analgesic activity; ii) Koster trial on the mouse for the peripheral analgesic activity.The evaluation of the central and peripheral analgesic activities for the pre cited extracts was realized after optimal doses determination of the global extracts activities for both species.The peripheral analgesic activity test on the mouse showed that, for 60 mg/kg intra peritoneum (IP), the hexanic, dichloromethanic, ethyl acetate and butanic extracts have a protection power against abdominal cramp respectively around 89.78%, 81.73%, 70.9% et 69.05% for Nepeta atlantica Ball, and arround 89.16%, 82.98%, 71.52% et 70.27% for Nepeta tuberosa L. ssp. reticulata.Central morphine like analgesic activity on the rat showed that, for both spices under 60 mg/kg IP, the central analgesic activity effect is significatly for two extracts only: dichloromethan and ethyl acetate.

Highly Hydrolytic Reuteransucrase from Probiotic Lactobacillus reuteri Strain ATCC 55730

Lactobacillus reuteri strain ATCC 55730 (LB BIO) was isolated as a pure culture from a Reuteri tablet purchased from the BioGaia company. This probiotic strain produces a soluble glucan (reuteran), in which the majority of the linkages are of the alpha-(1-->4) glucosidic type ( approximately 70%). This reuteran also contains alpha-(1-->6)- linked glucosyl units and 4,6-disubstituted alpha-glucosyl units at the branching points. The LB BIO glucansucrase gene (gtfO) was cloned and expressed in Escherichia coli, and the GTFO enzyme was purified. The recombinant GTFO enzyme and the LB BIO culture supernatants synthesized identical glucan polymers with respect to linkage type and size distribution. GTFO thus is a reuteransucrase, responsible for synthesis of this reuteran polymer in LB BIO. The preference of GTFO for synthesizing alpha-(1-->4) linkages is also evident from the oligosaccharides produced from sucrose with different acceptor substrates, e.g., isopanose from isomaltose. GTFO has a relatively high hydrolysis/transferase activity ratio. Complete conversion of 100 mM sucrose by GTFO nevertheless yielded large amounts of reuteran, although more than 50% of sucrose was converted into glucose. This is only the second example of the isolation and characterization of a reuteransucrase and its reuteran product, both found in different L. reuteri strains. GTFO synthesizes a reuteran with the highest amount of alpha-(1-->4) linkages reported to date.

Molecular characterization of a novel glucosyltransferase from Lactobacillus reuteri strain 121 synthesizing a unique, highly branched glucan with alpha-(1-->4) and alpha-(1-->6) glucosidic bonds.

Lactobacillus reuteri strain 121 produces a unique, highly branched, soluble glucan in which the majority of the linkages are of the alpha-(1-->4) glucosidic type. The glucan also contains alpha-(1-->6)-linked glucosyl units and 4,6-disubstituted alpha-glucosyl units at the branching points. Using degenerate primers, based on the amino acid sequences of conserved regions from known glucosyltransferase (gtf) genes from lactic acid bacteria, the L. reuteri strain 121 glucosyltransferase gene (gtfA) was isolated. The gtfA open reading frame (ORF) was 5,343 bp, and it encodes a protein of 1,781 amino acids with a deduced M(r) of 198,637. The deduced amino acid sequence of GTFA revealed clear similarities with other glucosyltransferases. GTFA has a relatively large variable N-terminal domain (702 amino acids) with five unique repeats and a relatively short C-terminal domain (267 amino acids). The gtfA gene was expressed in Escherichia coli, yielding an active GTFA enzyme. With respect to binding type and size distribution, the recombinant GTFA enzyme and the L. reuteri strain 121 culture supernatants synthesized identical glucan polymers. Furthermore, the deduced amino acid sequence of the gtfA ORF and the N-terminal amino acid sequence of the glucosyltransferase isolated from culture supernatants of L. reuteri strain 121 were the same. GTFA is thus responsible for the synthesis of the unique glucan polymer in L. reuteri strain 121. This is the first report on the molecular characterization of a glucosyltransferase from a Lactobacillus strain.

Studies on monoterpene glucosides and related natural products: XXXI. Gas chromatography and gas chromatography-mass spectrometry of iridoid and secoiridoid glucosides

A total of 33 iridoid and secoiridoid glucosides were detected by gas chromatography on several columns such as OV-1 or OV-17. Representative glucosides were then subjected to gas chromatography-mass spectrometry, giving some characteristic peaks that permitted the discrimination of both types of glucosides from other compounds in most instances. The successful detection of both types of glucosides in several plant extracts showed the applicability of this combination of methods to small amounts of plant materials.

The genus Comus: Non-flavonoid glucosides as taxonomic markers

Previous proposals for subdivision of the genus Cornus are reviewed. Twenty-seven authenticated Cornus species have been studied for their content of non-flavonoid glucosides. Two distinct groups of taxa can be distinguished on this basis: one, containing a hydroxycyclohexadienone glucoside, along with salidroside, its reduced counterpart, and the second, characterized by containing various iridoid glucosides. The two types of glucosides are apparently mutually exclusive.