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has been cited by the following article:

• TITLE: Extraction and Stability of Anthocyanins Present in the Skin of the Dragon Fruit (Hylocereus undatus)

  AUTHORS: María de Lourdes Vargasy Vargas, Jorge Abraham Tamayo Cortez, Enrique Sauri Duch, Andrés Pech Lizama, Carlos Hernán Herrera Méndez

  KEYWORDS: Anthocyanins; Dragon Fruit; Stability

  JOURNAL NAME: Food and Nutrition Sciences, Vol.4 No.12, November 29, 2013

  ABSTRACT: The extraction of anthocyanins present in the skin of the dragon fruit was performed using trifluoroacetic acid (TFA) plus a mixture of methanol, acetic acid and water; the anthocyanins were then purified with a LC-18 cartridge, using methanol acidified with TFA as eluent, reaching concentrations of 44.3865 ± 1.3125 mg/100g of sample. The extracts were put through stability tests under different storage conditions, modifying the pH of the extracts (pH of 1, 4 and 6), the temperature (4℃, 25℃ and 68℃) and the absence and presence of light for a time period of 4 days; the tests indiated that anthocyanins remain more stable at a temperature of 4℃with a pH of 4 in the absence of light, retaining up to 80% of the pigment. Three anthocyanins were partially identified in the extracts by high performance liquid chromatography (HPLC); they were: cyanidin 3-O-glucoside, cyanidin 3,5 O-glucoside and pelargonidin 3,5 O-glucoside.