Safeness of diets based on gluten-free buckwheat bread enriched with seeds and nuts—effect on oxidative and biochemical parameters in rat serum

Abstract

Buckwheat breads enriched with seeds (e.g., poppy, carum, amaranth, sunflower, and pumpkin) and nuts can be excellent sources of selected macro-and microelements and bioactive components, such as phenolics, essential oils, unsaturated fatty acids, fiber, and vitamins; however, no studies described their impacts on body biochemical parameters and antioxidant status. The aim of this study was to a determine the safety (the analyses of blood morphological and biochemical parameters) of short-term diets based on buckwheat breads supplemented with the commonly used functional ingredients. Additionally, we confirmed the usefulness of these fortified breads in a reduction of blood cholesterol and triacylglycerols, as well as an improvement of in vivo antioxidant status of Wistar rats. Enriched breads presented an increased phenolic content; however, it has not been translated into an elevation of antioxidant capacities. During short-term in vivo experiments, the studied breads increased the body mass of the rats, except the control buckwheat bread. Compared to the control, the poppy-milk bread markedly lowered (–23%) and egg yolk–carum bread significantly increased (+17%) the total cholesterol concentration in serum. All the fortified breads decreased triacylglycerols’ levels by about 50%. Bread enriched with the poppy–milk, milk-seed, egg yolk–carum, and a mix of additives decreased superoxide dismutase activity by 68%, 66%, 73%, and 71%, respectively. Catalase activity was significantly decreased in the rats fed with carum bread (–62%) and markedly increased in the groups fed with egg yolk–carum bread (+89%), hazel nuts–amaranth bread (+72%), and milk–seeds bread (+65%). The results confirmed the usefulness and safety of functional additives in buckwheat breads.