Effects of acetylation and succinylation on the physicochemical properties of the canola 12S globulin. Part I

Application Potential of Food Protein Modification

“…Large extents of succinylation have been reported to affect the integrity of secondary and tertiary structure of soy protein hydrolysate as shown by intrinsic tryptophan fluorescence and circular dichroism (Achouri & Zhang, 2001). Similar conformational rearrangements have been reported upon succinylation of whey protein isolate (Gruener & Ismond, 1997), bovine serum albumin (Jonas & Weber, 1970), canola protein (Lakkis & Villota, 1992), Faba bean legumin (Schwenke et al, 1998), rapeseed 12S globulin (Gueguen et al, 1990), and winged bean protein (Narayana & Rao, 1991). As a result of co-incubation of soy protein hydrolysate with succinic anhydride, which is a common compound used to succinylate proteins, heterogeneous reaction mixtures were obtained.…”

Effect of maleylation on physicochemical and functional properties of rapeseed protein isolate

“…1b) and the rate of reaction depends on the rate of nucleophilic attack: the π-electrons on the double bond of MA hinder the nucleophilic attack of the amino group (Lawal and Dawodu 2007). This may be one of the causes for lower level of modification in this study compared to those obtained by succinylation of canola 12S protein (Gruener and Ismond 1997). Even at the highest level of anhydride-to-protein ratio, not all free amino groups were maleylated.…”

“…Trinitrobenzene sulphonic acid (TNBS) method for free amino groups estimation was used for determining modification level (Gruener and Ismond 1997). One millilitre each of 0.05 M Na 2 HPO 4 and 0.1 % TNBS were added to 1 ml of protein solution (1 % w/v in 0.05 M NaCl, pH 9.2), which was then allowed to react at 60°C water-bath for 2 h. To stop the reaction, 1 ml of 10 % SDS was added, followed by 0.5 ml of 1 N HCl.…”

“…For the above-stated reason, efforts have been made to improve the functionalities of oilseed proteins, and probably, the best documented of these efforts involve chemical and enzymatic modifications. Numerous investigations through chemical modification (succinylation, acetylation, phosphorylation and sulfamidation) or enzymatic modification of rapeseed proteins have been undertaken (Gruener and Ismond 1997;Gerbanowski et al 1999;Schwenke et al 2000;Sánchez-Vioque et al 2004); however, proteolysates from the latter method are frequently bitter and lacks satisfactory foam/emulsion stability (Franzen and Kinsella 1976). Moreover, there are indications that all peptides do not contribute equally to the reported biological activities and thus the purification of active peptides is needed (Aachary and Thiyam 2012), making it a cumbersome and expensive technique.…”

“…Succinylation and acetylation have both been used to modify canola proteins with the degree of modification varying upto 62 % acetylation or succinylation (Gruener and Ismond 1997), 84 % succinylation (Paulson and Tung 1989) and 93 % succinylation (Gueguen et al 1990). For canola, low levels of modification led to improved foaming and emulsifying activities due to improved interfacial absorption kinetics (Gueguen et al 1990), but foam stability was adversely affected by acylation and emulsion stability decreased at higher levels of modification (Gruener and Ismond 1997). Heat-induced gel characteristics were also improved with the firmest gels being obtained at intermediate levels of succinylation (Paulson and Tung 1989).…”