Magenta‑α‑Glc

Magenta‑α‑Glc (CAS 878495‑64‑8) is a synthetic α‑D‑glucosidase‑specific chromogenic substrate in which 5‑bromo‑6‑chloro‑3‑indoxyl is linked via an α‑glycosidic bond to D‑glucose. When hydrolyzed by α‑D‑glucosidase (EC 3.2.1.20) or glucosidase‑containing systems, the indoxyl moiety is released and undergoes aerial oxidation to form an insoluble magenta‑colored indigo‑type precipitate, enabling clear visual detection of enzyme activity. This substrate is commonly incorporated into selective agar media to screen and differentiate α‑glucosidase‑producing bacteria and yeasts, as well as in enzyme‑kinetic assays for recombinant or purified α‑D‑glucosidases. The distinct magenta color improves contrast compared with standard blue‑forming indoxyl derivatives, making Magenta‑α‑Glc particularly useful for multiplex assays or mixed‑microbe systems where clear color discrimination is required. It is compatible with standard laboratory buffers and culture‑medium matrices, and is recommended for research‑use‑only applications.

Appearance

• Off‑white to pale yellow crystalline powder or lyophilized solid.
• Free‑flowing, fine‑particle material suitable for precise weighing and dissolution in aqueous or mixed aqueous‑organic solvents.

Source / synthesis

• Synthetically produced by coupling 5‑bromo‑6‑chloro‑3‑indoxyl with α‑D‑glucose under glycosylation conditions to form the α‑D‑glucopyranoside derivative.
• Commercially manufactured by specialty carbohydrate and enzyme‑substrate suppliers as a high‑purity, research‑grade reagent (e.g., Geneseq, Hepattack, and similar vendors).

Molecular weight and structure

• Molecular formula: C14H15BrClNO6\text{C}_{14}\text{H}_{15}\text{BrClNO}_{6}C14​H15​BrClNO6​.
• Molecular weight: 408.63 g/mol.
• Structure: 5‑bromo‑6‑chloro‑1H‑indol‑3‑yl α‑D‑glucopyranoside, with an α‑glycosidic linkage between the indole C3‑O and the D‑glucose ring, typically in the (2R,3R,4S,5S,6R) configuration.

Sugar specificity

• Specifically hydrolyzed by α‑D‑glucosidases (EC 3.2.1.20) and related α‑D‑glucose‑cleaving glycosidases.
• Shows minimal cross‑reactivity with other α‑glycosidases (e.g., α‑galactosidase, α‑fucosidase) and β‑glycosidases when used under optimized assay conditions.

Biological activity

• Acts as a chromogenic reporter for α‑D‑glucosidase‑mediated hydrolysis of α‑D‑glucosyl linkages in glucosides, disaccharides, and oligosaccharides.
• Enzymatic cleavage yields 5‑bromo‑6‑chloro‑3‑indoxyl, which oxidizes and dimerizes into a magenta‑colored, water‑insoluble precipitate, providing a sensitive, low‑background readout for solution and solid‑medium assays.

Purity and microbial contamination

• Typically supplied at ≥98% purity as determined by HPLC or similar analytical methods.
• Certificates of analysis from major suppliers generally confirm low residual solvents, acceptable heavy‑metal content, and absence of significant microbial contamination when stored and handled aseptically.

Identity and quality control

• Identity confirmed by NMR, HPLC, MS, and elemental analysis, with batch‑specific certificates of analysis provided by manufacturers.
• Quality‑control parameters often include checks for appearance, solubility, UV/Vis spectral data, and enzyme‑activity performance in a defined α‑D‑glucosidase assay system.

Shelf life and storage

• Shelf life is usually 12–24 months when stored as a dry powder at –20 °C in a tightly sealed container, protected from moisture and light.
• Aqueous working solutions are recommended to be prepared immediately before use or stored frozen for short periods to minimize degradation and nonspecific oxidation of the indoxyl moiety.

Application

• Screening and phenotypic differentiation of α‑D‑glucosidase‑producing microorganisms (e.g., yeasts, bacteria) on selective agar media.
• Enzyme‑activity assays for recombinant or purified α‑D‑glucosidases in solution or immobilized formats.
• Histochemical or cytochemical localization of α‑D‑glucosidase activity in tissue sections and cell preparations.

Key characteristics

• High sensitivity and low background due to formation of an insoluble magenta‑colored dye upon α‑D‑glucosidase hydrolysis.
• Defined α‑D‑glucopyranoside linkage providing selectivity for α‑D‑glucosidases over other glycosidases.
• Crystalline, stable powder with a known molecular formula and weight, suitable for quantitative enzyme assays and standardized media formulations.

citations

• Geneseq (金赛途) – Magenta‑α‑Glc product page: http://www.geneseqtools.com/en/product03_cid_213_pid_508.html
• Geneseq Chinese entry for Magenta‑α‑Glc (洋红色‑α‑葡萄糖苷): http://www.geneseqtools.com/cn/product03_cid_213_pid_508.html
• PubChem – 5‑Bromo‑6‑chloro‑3‑indolyl α‑D‑glucopyranoside entry (CAS 878495‑64‑8): https://pubchem.ncbi.nlm.nih.gov/compound/5-Bromo-6-chloro-3-indolyl-alpha-D-glucopyranoside
• GuideChem China – 878495‑64‑8 洋红色‑α‑葡萄糖苷 (Magenta‑α‑Glc) data page: https://china.guidechem.com/3219376/detail.html
• Hepattack – Magenta‑α‑Glc entry in product catalog (CAS 878495‑64‑8): https://www.hepattack.com/en/product02_page_3.html
• ZellX – X‑α‑Glc (5‑bromo‑4‑chloro‑3‑indolyl α‑D‑glucopyranoside) product page (for dye‑chemistry and assay‑format reference): https://zellx.de/product/5-bromo-4-chloro-3-indolyl-%CE%B1-d-glucopyranoside-x-%CE%B1-glc/
• ChemImpex – 6‑Chloro‑3‑indoxyl‑α‑D‑glucopyranoside product entry (for α‑glucoside substrate usage pattern): https://www.chemimpex.com/products/21034
• ACS Omega – α‑glucosidase assay paper (enzyme‑substrate concept reference): https://pubs.acs.org/doi/10.1021/acsomega.2c06991
• Taylor & Francis / Enzyme‑model article (α‑glucosidase characterization): https://www.tandfonline.com/doi/full/10.1080/14756366.2025.2468859
• General enzyme‑substrate overview (X‑ and Magenta‑type substrates): https://www.hepattack.com/en/product02_page_3.html (section listing Magenta‑α‑Glc and related dyes)