Identification and Determination of Betacyanins in Fruit Extracts of Species.

Betacyanin pigments were studied in edible fruits of four species, Pfeiff., (Britton & Rose) Luetzelb, (Hoffm.) Pfeiff., and Pfeiff., by means of chromatographic and mass spectrometric techniques. The main pigment constituent, melocactin, endogenously present in the species, was identified as betanidin 5--β-sophoroside betacyanin, previously known as "bougainvillein-r-I". The highest total concentration of betacyanins was found in fruits of (∼0.08 mg/g). Except for melocactin being the most abundant betacyanin (34.8-38.8%) in the analyzed species, a presence of its malonylated derivative, mammillarinin (15.2-19.9%), as well as more hydrophobic feruloyled and sinapoyled melocactins was confirmed by additional co-chromatographic experiments with authentic reference betacyanins. The acyl migration isomers of the malonylated betacyanins as well as a presence of 5''---sinapoyl-2'--apiosyl-betanin (2.3-3.0%) found frequently in light-stressed cacti was also acknowledged.