Product description
Anthocyanins are water-soluble natural pigments widely found in plants in nature, but they often exist in the form of glycosides with various monosaccharides, known as anthocyanidins. They are water-soluble pigments in plant cells, present in almost all terrestrial plants' roots, stems, leaves, flowers, and fruits; and they also have strong antioxidant activity, capable of scavenging free radicals. This kit uses the pH differential method, where the color of anthocyanidins changes with pH values, while the characteristic spectra of interfering substances do not change with pH. At pH 1, anthocyanidins exist in the form of red 2-phenylbenzopyrylium. At pH 4.5, anthocyanidins exist in the form of colorless methanol pseudo-base. By determining the two pH values that show the greatest difference in absorbance for anthocyanidins but are stable for anthocyanidins (generally choosing pH values of 1.0 and 4.5), the absorbance difference at the maximum absorption wavelength of 700 nm is proportional to the content of anthocyanidins, and the total anthocyanidin content can be calculated.
Additional Materials and Equipments Required
Spectrophotometer, 1mL glass cuvette (light path 1cm), water bath, pipette, mortar, and distilled water.