Estudos de métodos alcalino/precipitação isoéletrica para extração e quantificação de proteína da farinha obtida das folhas da pereskia aculeata Miller (ora-pro-nóbis)

Abstract

The search for alternative sources of proteins and other bioactive compounds has been the focus of numerous studies over the past decade, aiming to meet the demands of different consumer groups, such as flexitarians. In this context, the present work aimed to evaluate non-enzymatic methods for the extraction and quantification of proteins from the leaves of Pereskia aculeata Miller (ora-pro-nóbis), with the goal of paving the way for a better understanding of its biological functions, industrial applications, and the development of new food products, as well as stimulating scientific research on this Non-Conventional Edible Plant (PANC) with high nutritional potential.extraction/isoelectric precipitation methods were tested under conventional conditions and in combination with ultrasound, followed by protein quantification using the Kjeldahl method. The results showed that alkaline extraction with NaOH 2 M and HCl 2 M yielded the highest protein recovery (24.16%), whereas the combination with ultrasound did not enhance extraction efficiency, resulting in lower yields (18.92% and 7.29%). The presence of mucilage in the leaves was identified as a limiting factor, forming protein–polysaccharide complexes that reduced protein recovery, but also representing a potential technological resource due to its thickening and stabilizing properties. These findings reinforce the value of ora-pro-nóbis as an alternative source of plant protein and highlight the need for optimization of extraction protocols to balance yield, structural integrity, and technological applicability.