%0 Journal Article
%T Comparative Evaluation of a Modified Acetic Method for Extraction of Antioxidant Compounds from Black Beans (<i>Phaseolus vulgaris</i>)
%A Jose F. Islas
%A Alfredo J. D¨¢valos-Balderas
%A Netzahualc¨®yotl Arroyo-Curr¨¢s
%A Beiman G. Cano
%A Paulina Galindo-Jacobo
%A Gustavo Guajardo-Salinas
%A Angel Gaytan-Ramos
%A Jorge E. Moreno-Cuevas
%J Food and Nutrition Sciences
%P 348-353
%@ 2157-9458
%D 2012
%I Scientific Research Publishing
%R 10.4236/fns.2012.33050
%X Extraction of phenolic compounds from bean seed coats by acetic acid was evaluated and compared to conventional extraction with 80% methanol. Total phenols, flavonoids and free radical scavenging capacity were determined by colorimetric methods. Furthermore, qualitative flavonoid characterization was performed via HPLC diode array. The acetic acid extract contained 73.4 ¡À 7 mg/g of sample expressed as gallic acid equivalents (GAE), and 41.3 ¡À 4 mg/g as catechin equivalents (CE). The acetic acid extract (at 1 mg/mL) showed over 89% efficiency to scavenge the 1,1 diphenyl-2-picrylhydrazil (DPPH) radical (EC<sub>50</sub> = 6.13 mg extract/mg standard). Gallic acid, delphinidin-3-glycoside, petunidinglycoside, petunidin, malvidin-3-glycoside, myricetin-glycoside, quercitin-glycoside, saponin (<i>¦Â</i>-g), and 3-hydroxy-5, 7-megastigmadien-9-one were identified in both extracts. Additionally, kaempferol-3-glycoside was found in the acetic acid extract. Sequential acetic acid extractions indicated that the antiradical activity was about 90% in DPPH radical scavenging within the first 8 h of extraction, when compared to a 24 h extraction. In general, acetic acid offered a faster and more efficient approach for the extraction of phenolic
%K Acetic Acid
%K Antioxidants
%K DPPH Scavenging
%K Extraction
%K Black Beans
%U http://www.scirp.org/journal/PaperInformation.aspx?PaperID=17966