Determination of carbohydrates in medicinal plants--comparison between TLC, mf-MELDI-MS and GC-MS

Discovery and Biotechnological Exploitation of Glycoside-Phosphorylases

Among carbohydrate active enzymes, glycoside phosphorylases (GPs) are valuable catalysts for white biotechnologies, due to their exquisite capacity to efficiently re-modulate oligo- and poly-saccharides, without the need for costly activated sugars as substrates. The reversibility of the phosphorolysis reaction, indeed, makes them attractive tools for glycodiversification. However, discovery of new GP functions is hindered by the difficulty in identifying them in sequence databases, and, rather, relies on extensive and tedious biochemical characterization studies. Nevertheless, recent advances in automated tools have led to major improvements in GP mining, activity predictions, and functional screening. Implementation of GPs into innovative in vitro and in cellulo bioproduction strategies has also made substantial advances. Herein, we propose to discuss the latest developments in the strategies employed to efficiently discover GPs and make the best use of their exceptional catalytic properties for glycoside bioproduction.

Pharmacological and pharmacognostical valuation of Canna indica leaves extract by quantifying safety profile and neuroprotective potential

The current study primarily focused on the pharmacognostical and phytochemical screening of Canna indica and further analyzing the leaves extract for toxicological profile and neuroprotective potential. The microscopic, dry powder properties of the leaf material and phytochemical, physicochemical analysis was evaluated for pharmacognostical assessment. Dry leaves of C. indica were extracted using methanol and then further studied for both in vitro and in vivo toxicological study. The acute toxicity was measured by estimating the antioxidant defense system and anatomical impairment in the rat's organs. Also, the neuroprotective activity of the plant extract was assessed using anticholinesterase enzymatic inhibitory assay. The extract was found to be hemocompatible and showed absences of induction of behavioural changes. Likewise, no changes were seen on the anatomical structure of the rat's organs. The methanolic extract portrayed a significant upsurge in the reduced glutathione level and showed a comparable acetylcholinesterase inhibition in a dosedependent manner with an IC50 value of 14.53 μg/mL compared to the standard Donepezil with an IC50 value of 13.31 μg/mL. C. indica has compelling pharmacognostical characteristics, good safety reports, and significant antioxidant as well as the neuroprotective potential that shows great potential for its further in-depth research for pharmacological use.

Pharmacognostic and pharmacological evaluation of Eulaliopsis binata plant extracts by measuring in vitro/in vivo safety profile and anti-microbial potential

The present investigation emphasizes the pharmacognostic and phytochemical screening of Eulaliopsis binata and further evaluates the extracts of this plant for toxicological profile and anti-bacterial potential based on in vivo/in vitro assays. Microscopy, powder characteristics of the leaf material, and physicochemical and phytochemical screening were assessed for pharmacognostic evaluation. Dry leaves of Eulaliopsis binata were extracted using different solvents (methanol, ethyl acetate, and hexane), and the extracts obtained were further investigated for in vitro/in vivo toxicological study. Moreover, acute toxicity was assessed by evaluating the anti-oxidant defense system and anatomical damage in vital organs. In addition, anti-bacterial activity of all the extracts was assessed by the Kirby-Bauer method. Physicochemical and microscopic observations showed the unique identification mark for leaf powder and leaf transverse section. Phytochemical investigation evidenced the presence of flavonoids and phenolic contents in the methanolic extract. All extracts were found to be hemocompatible and exhibited no induction of behavioral alteration and no alteration in the anti-oxidant potential and anatomical structure of the vital organs. On the other hand, the methanolic extract showed a significant upsurge in the reduced glutathione level, whereas all extracts showed significant anti-bacterial potential in a dose-dependent manner. Eulaliopsis binata has inimitable pharmacognostical characteristics, good safety profile and significant anti-oxidant and anti-bacterial potential that show immense possibility for its further investigation for pharmacological use.

Analysis of carbohydrates and glycoconjugates by matrix-assisted laser desorption/ionization mass spectrometry: An update for 2011-2012

This review is the seventh update of the original article published in 1999 on the application of MALDI mass spectrometry to the analysis of carbohydrates and glycoconjugates and brings coverage of the literature to the end of 2012. General aspects such as theory of the MALDI process, matrices, derivatization, MALDI imaging, and fragmentation are covered in the first part of the review and applications to various structural types constitute the remainder. The main groups of compound are oligo- and poly-saccharides, glycoproteins, glycolipids, glycosides, and biopharmaceuticals. Much of this material is presented in tabular form. Also discussed are medical and industrial applications of the technique, studies of enzyme reactions, and applications to chemical synthesis. © 2015 Wiley Periodicals, Inc. Mass Spec Rev 36:255-422, 2017.

GC-MS Method for the Quantitation of Carbohydrate Intermediates in Glycation Systems

Glycation is a ubiquitous nonenzymatic reaction of carbonyl compounds with amino groups of peptides and proteins, resulting in the formation of advanced glycation end-products (AGEs) and thereby affecting the properties and quality of thermally processed foods. In this context, mechanisms of the Maillard reaction of proteins need to be understood; that is, glycation products and intermediates (α-dicarbonyls and sugars) need to be characterized. Although the chemical analysis of proteins, peptides, and α-dicarbonyls is well established, sensitive and precise determination of multiple sugars in glycation mixtures is still challenging. This paper presents a gas chromatography-mass spectrometry (GC-MS) method for absolute quantitation of 22 carbohydrates in the model of phosphate-buffered glycation systems. The approach relied on the removal of the phosphate component by polymer-based ion exchange solid phase extraction (SPE) followed by derivatization of carbohydrates and subsequent GC-MS analysis. Thereby, baseline separation for most of the analytes and detection limits of up to 10 fmol were achieved. The method was successfully applied to the analysis of in vitro glycation reactions. Thereby, at least seven sugar-related Maillard reaction intermediates could be identified and quantified. The most abundant reaction product was d-fructose, reaching 2.70 ± 0.12 and 2.38 ± 0.66 mmol/L after 120 min of incubation in the absence and presence of the model peptide, respectively.