Solubilization, Fractionation, and Electrophoretic Characterization of Inca Peanut (Plukenetia volubilis L.) Proteins

Abstract

Effects of different solvents, ionic strength, and pH on Inca peanut seed protein solubility were assessed by quantitatively analyzing solubilized proteins using Lowry and Bradford methods. Soluble proteins were fractionated using Osborne procedure and the polypeptide composition of solubilized proteins was determined by one dimensional 25 % monomer acrylamide linear gradient SDS-PAGE. Osborne protein fractions were analyzed by the 2D gel electrophoresis. Total seed proteins were efficiently solubilized by 2 M NaCl among the tested solvents. The soluble seed proteins registered a minimum solubility at pH ~4.0. Osborne protein fractions, albumins, globulins, prolamins, and glutelins accounted for 43.7, 27.3, 3.0, and 31.9 %, respectively, of the total aqueous soluble proteins. Soluble seed flour proteins are mainly composed of polypeptides in the MW range of 6-70 kDa of which the predominant polypeptides were in the 20-40 kDa range. Prolamin fraction was mainly composed of four polypeptides (MW < 15 kDa). Glycoprotein staining indicated 32-35 and <14 kDa peptides to be positive.

Identification of peanut seed prolamins with an antifungal role by 2D-GE and drought treatment

“…Although the native prolamins are hydrophobic and extractable by high alcohol concentration, polypeptides with acidic pIs to basic pIs were also published for the prolamins of Inca peanut and rice. 32,33) The results revealed six major constitutive polypeptides with sizes of 30.5, 28.5, and 22 kDa at pI 5.45-5.75 restrictedly in seed prolamins of the Spanish-type peanuts (Fig. 3(A-J)).…”

“…31) Therefore, the antifungal activity of the prolamin fractions should not be from 2S albumins. The profiles could not be compared to those of another legume, 32) because of species difference or the extraction method. This study provided the first 2D-GE maps for peanut prolamins which were resolved in the pH range of 4.5-9.8 (Fig.…”

PERFIL DE PROTEÍNAS DE LAS SEMILLAS DE “SACHA INCHI” (PLUKENETIA VOLUBILIS L. Y PLUKENETIA HUAYLLABAMBANA BUSSMANN, TÉLLEZ & GLENN)

“…El fraccionamiento de las proteínas para P. volubilis que nosotros hemos estudiado no coincide con lo hallado por Sathe et al (2012), quienes emplearon la misma especie de "Sacha Inchi" (Departamento San Martín) y el método de Osborne. Sus resultados muestran como fracción mayoritaria a las albúminas (43,7 %), seguidas de las globulinas (27,3%), mientras que en nuestros resultados la fracción mayoritaria son las globulinas (39,79%), seguidas por las albuminas (37,10%), gliadinas o prolaminas (13,93%) 15,4%, glutelinas 1,3%, prolaminas 0%), lupinus (globulinas 45,4% albúminas 15,5%, glutelinas 8,4%, prolaminas 2,4%), semillas de algodón (globulinas 38,1%, albúminas 6,3%, glutelinas 2,4% y prolaminas 0%) y semillas de chía (globulinas 52%, albúminas 17,3%, prolaminas 12,7% y glutelinas 14,5%) (Nikokyris & Kandylis 1997, Vázquez-Ovando et al 2009, Sandoval 2012).…”

Identification of Fatty Acids in Sacha Inchi Oil (Cursive Plukenetia Volubilis L.) From Ecuador

“…This plant belongs to the Euphorbiaceae family and is composed of nineteen species [1]. It is known that sacha inchi seeds have a high content of oil (35-60 %) and proteins (27%) and contain heat-labile substances with a bitter taste [2].…”