Obtention of protein concentrate and polyphenols from Macadamia (Macadamia integrifolia) with aqueous extraction method

Objective: The aim of this study was to obtain protein concentrates from Macadamia using alkaline pH at different pHs of precipitation with water to analyze the protein isolates using the native-polyacrylamide gel electrophoresis (PAGE), sodium dodecyl sulfate-PAGE (SDS-PAGE) electrophoresis, and reversed-phase high-performance liquid chromatography (RP-UHPLC) methods. Methods: Macadamia protein concentrates were obtained using the isoelectric precipitation method at different pHs using water as solvent. Proteins were analyzed using the native-PAGE, SDS-PAGE electrophoresis, and RP-UHPLC methods. Results: A yield of 36.57±0.17^a of protein concentrate of defatted Macadamia flour at pH 6.0 with a 51.564% of protein was obtained using the Dumas method. Polypeptides profile was identified in the 11-63 kDa range. Total polyphenols content was high at pH 5.0 with a value of 367,340 mg gallic acid equivalent equivalents/100 g. Conclusions: Macadamia seed is a good source of proteins. Native-PAGE, SDS-PAGE, and RP-UHPLC are good methods to identify the Macadamia protein isolate in the presence of water.