ABSTRACT
Abstract The Brazilian Cerrado presents a wide variety of natural products, including the Pequi (Caryocar brasiliense). The important factor that determines the dietary and nutritional ideality of protein is degestitibility. This work aims to evaluate the protein digestibility of Pequi seeds and the presence of anti-nutritional factors. The protein Pequi almonds were extracted, toasted and untoasted. Evaluation digestibility was structurally characterized by SDS-PAGE 15%, which can be used to analyze simulated gastric fluid (SFG) and digestion in intestinal fluid (SFI) in the presence of pepsin and trypsin/chymotrypsin. The extract from Pequi almonds showed inhibitory activity and was not detected hemagglutination. The intensity of the bands according to 2S albumins, after heat treatment, did not decrease in comparison to the condition native, significantly. In the crisp crude extract, which was incubated under SGF and SIF, the intensity of the corresponding bands at 8 and 3 kDa was resistant to SGF and indigestible after 4 hours under SIF. The characterization of Pequi almonds demonstrated that the product of the crude extract has anti-nutritional factors, which were confirmed by evaluating digestibility.
ABSTRACT
Ricinus communis L. is of great economic importance due to the oil extracted from its seeds. Castor oil has been used for pharmaceutical and industrial applications, as a lubricant or coating agent, as a component of plastic products, as a fungicide or in the synthesis of biodiesel fuels. After oil extraction, a castor cake with a large amount of protein is obtained. However, this by-product cannot be used as animal feed due to the presence of toxic (ricin) and allergenic (2S albumin) proteins. Here, we propose two processes for detoxification and allergen inactivation of the castor cake. In addition, we establish a biological test to detect ricin and validate these detoxification processes. In this test, Vero cells were treated with ricin, and cell death was assessed by cell counting and measurement of lactate dehydrogenase activity. The limit of detection of the Vero cell assay was 10 ng/mL using a concentration of 1.6 x 10(5) cells/well. Solid-state fermentation (SSF) and treatment with calcium compounds were used as cake detoxification processes. For SSF, Aspergillus niger was grown using a castor cake as a substrate, and this cake was analyzed after 24, 48, 72, and 96 h of SSF. Ricin was eliminated after 24 h of SSF treatment. The cake was treated with 4 or 8% Ca(OH)2 or CaO, and both the toxicity and the allergenic properties were entirely abolished. A by-product free of toxicity and allergens was obtained.