Search results
Results From The WOW.Com Content Network
Bloom is a test used to measure the strength of a gel, most commonly gelatin.The test was originally developed and patented in 1925 by Oscar T. Bloom. [1] The test determines the weight in grams needed by a specified plunger (normally with a diameter of 0.5 inch) to depress the surface of the gel by 4 mm without breaking it at a specified temperature. [2]
[1] Zymography is an electrophoretic technique for the detection of hydrolytic enzymes, based on the substrate repertoire of the enzyme. Three types of zymography are used; in gel zymography, in situ zymography and in vivo zymography. [2] For instance, gelatin embedded in a polyacrylamide gel will be digested by active gelatinases run
A gallotannin is any of a class of molecules belonging to the hydrolysable tannins. Gallotannins are polymers formed when gallic acid, a polyphenol monomer, esterifies and binds with the hydroxyl group of a polyol carbohydrate such as glucose.
50 mg of sample tannin in 5 ml 2N H 2 SO 4 are put into constricted test tubes and frozen. The tubes are vacuum-sealed and heated for 24 hours at 100 °C. The tubes are cooled, opened and the contents made up to 50 ml with water. Then 1.5 ml of freshly prepared 0.667% w/v rhodanine in methanol and 1 ml of sample are mixed. After exactly 5 min 1 ...
In red musts, this increases color and tannin extraction. [2] After fermentation, the force of gravity may eventually cause the wine to "fall bright" or clarify naturally, as the larger suspended particles gradually settle to the bottom of the storage vessel. The wine can then be siphoned or "racked" off the compact solids into a new container. [3]
Vanillin–HCl staining (10% vanillin and 90% of a mixture of ethanol and HCl, giving an orange color) can be used to visualize the localisation of tannins in cells. The localization of phlorotannins can be investigated by light microscopy after vanillin–HCl staining. [1] The phlorotannins can be seen this way in physodes in brown algae.
The ellagitannins are a diverse class of hydrolyzable tannins, a type of polyphenol formed primarily from the oxidative linkage of galloyl groups in 1,2,3,4,6-pentagalloyl glucose. Ellagitannins differ from gallotannins, in that their galloyl groups are linked through C-C bonds, whereas the galloyl groups in gallotannins are linked by depside ...
The Folin–Ciocâlteu reagent (FCR) or Folin's phenol reagent or Folin–Denis reagent, is a mixture of phosphomolybdate and phosphotungstate used for the colorimetric in vitro assay of phenolic and polyphenolic antioxidants, also called the gallic acid equivalence method (GAE). [1] It is named after Otto Folin, Vintilă Ciocâlteu, and Willey ...