Assessing the Sensitizing and Allergenic Potential of the Albumin and Globulin Fractions from Amaranth (Amaranthus hypochondriacus) Grains before and after an Extrusion Process
Food Science and Technology Post-Grade, Chemistry-Biological Sciences Faculty, University of Sinaloa, Culiacán 80019, Sinaloa, Mexico
Nutrition Sciences Academic Unit, University of Sinaloa, Culiacán 80019, Sinaloa, Mexico
Department of Chemical and Biological Sciences, University of Sonora, Hermosillo 83000, Sonora, Mexico
Division of Sciences and Engineering, Department of Chemical, Biological, and Agricultural Sciences, University of Sonora, Navojoa 85880, Sonora, Mexico
Authors to whom correspondence should be addressed.
Medicina 2019, 55(3), 72; https://doi.org/10.3390/medicina55030072
Received: 22 December 2018 / Revised: 13 March 2019 / Accepted: 14 March 2019 / Published: 20 March 2019
(This article belongs to the Special Issue Food Allergies)
Background: The first cases of food allergy to amaranth grain have recently been published. This pseudocereal is considered hypoallergenic, and there is scarce information about the allergenic potential of amaranth proteins, either before or after food processing. Objective: To evaluate, in a mouse model of food allergy, the sensitizing and allergenic potential of extruded and non-extruded albumin and globulin fractions from amaranth grains. Materials and Methods: Amaranth (Amaranthus hypochondriacus) flour was obtained and the albumin and globulin fractions isolated. These protein fractions were also obtained after flour extrusion. An intraperitoneal 28-day protocol was carried out to evaluate the sensitizing and allergenic potential of the proteins. The common and rarely allergenic proteins ovalbumin and potato acidic phosphatase were utilized as reference. Specific IgE and IgG antibodies were evaluated for all the proteins tested. Mast cell protease-1 (mMCP-1) responses were evaluated in serum samples collected after intragastric challenges with the proteins of interest. All serological evaluations were carried out using ELISA. Results: Mice were sensitized to the non-extruded albumin fraction from amaranth grains and to ovalbumin (p = 0.0045). The extrusion process of amaranth proteins abrogated the IgE responses triggered under non-extruded conditions (p = 0.0147). mMCP-1 responses were significantly detected in the group of mice sensitized to ovalbumin (p = 0.0138), but not in others. Conclusions: The non-extruded albumin fraction from amaranth has the potential to sensitize BALB/c mice, but this sensitizing potential fails to induce detectable serum levels of the mast cell degranulation marker mMCP-1 after intragastric challenges. Furthermore, the extrusion process abolished the sensitization potential of the amaranth albumins.