Special attention is being paid to the study of amaranth proteins. They are characterized by a high biological value that significantly exceeds those of grain crops. The production of protein concentrate from amaranth flour includes preliminary enzymatic hydrolysis, extraction of the resulting mixture, protein precipitation, microfiltration, and freeze-drying. In our study, the obtained amaranth protein concentrate was limited by valine, with an amino acid score of 74%. The true digestibility of the amaranth protein concentrate determined in vivo was 97.6 ± 0.3%, which was significantly lower than that of casein (99.3 ± 0.2%). The protein digestibility-corrected amino acid score value of the concentrate was 72.2%. The obtained concentrate was a rich source of selenium, copper, magnesium, manganese, and iron. Ferulic acid was the only polyphenolic compound found in the amaranth protein concentrate, but its content was significantly greater compared to the original flour. Saponins were not removed completely during the process of obtaining the amaranth protein concentrate. We identified 15 saponins in the concentrate, mainly of the bidesmoside type, the sapogenins of which are related derivatives of oleanolic acid. Thus, the developed amaranth protein concentrate can be used as an ingredient in functional food products, with a high biological value.

The variety of stressful conditions in daily human activity requires nutritional support with safe, specialized food products containing functional food ingredients (FFIs) enriched with biologically active plant substances with proven adaptogenic properties. In this in vivo study, by evaluating a set of physiological parameters and biochemical markers, we investigated the effectiveness of the developed FFIs from Chenopodium quinoa grains in stress conditions induced by daily episodes of immobilization for 36 days. The results of the evaluation of the anxiety-like functions, locomotor, and search activity of rats in the “open field” and “elevated plus maze” tests demonstrated the ability of FFIs to reduce stressful behavior induced by immobilization. The improvement in the long-term memory of animals treated with FFIs was noted in the passive avoidance test. Together with the hypolipidemic effect and compensation of transaminase levels, FFIs normalized the excretion of catecholamines in the urine and reduced the levels of malondialdehyde to values of the control group. According to the results of the assessment of FFI acute oral toxicity, the LD₅₀ value exceeded 5000 mg/kg of body weight, which categorizes the FFIs under hazard class 5—substances with low hazard. The conducted experiment demonstrated the effectiveness of nutritional support with FFIs on the selected stress model. The positive safety profile of FFIs makes them reasonable to study on other stress models and to conduct clinical testing as part of specialized food products in various categories of people exposed to chronic stress.

Increasing the ability of the human body to adapt in conditions of physical or emotional stress is promising from the standpoint of the use of preventive nutrition containing functional food ingredients (FFI) with proven effectiveness in complex physiological in vivo studies. In this work, we developed FFI from spinach leaves (Spinacia oleracea L.) with a high content of polyphenols and adaptogens—phytoecdysteroids. Using in vivo models of increased physical activity and immobilization-induced emotional stress, we evaluated the nonspecific resistance of rats in response to the addition of the developed FFI to the diet. In the acute toxicity experiment, we found no signs of FFI toxicity up to 5000 mg/kg body weight. As a result of the daily 26-day consumption of FFI, we observed an anxiolytic effect in physiological studies. FFI prevented an increase in the content of biogenic amines in the blood, the main markers of the stress system, and had a positive effect on the lipid metabolism of the rats. The obtained results demonstrate a “smoothing” effect on the body’s reaction in response to induced stress conditions.

Adequate experimental animal models play an important role in an objective assessment of the effectiveness of medicines and functional foods enriched with biologically active substances. The aim of our study was a comparative assessment of the effect of consumption of 1 or 2% cholesterol with and without regular (two times a week), moderate running exercise on the main biomarkers of lipid and cholesterol metabolism, as well as the intestinal microbiota of male Wistar rats. In experimental rats, a response of 39 indicators (body weight, food consumption, serum biomarkers, liver composition, and changes in intestinal microbiota) was revealed. Total serum cholesterol level increased 1.8 times in animals consuming cholesterol with a simultaneous increase in low-density lipoprotein cholesterol (2 times) and decrease in high-density lipoprotein cholesterol (1.3 times) levels compared to the control animals. These animals had 1.3 times increased liver weight, almost 5 times increased triglycerides level, and more than 6 times increased cholesterol content. There was a tendency towards a decrease in triglycerides levels against the background of running exercise. The consumption of cholesterol led to a predominance of the Bacteroides family, due to a decrease in F. prausnitzii (1.2 times) and bifidobacteria (1.3 times), as well as an increase in Escherichia family (1.2 times). The running exercise did not lead to the complete normalization of microbiota.

The aim of our study was a comprehensive comparative assessment of the effect of consumption of 1 and 2% cholesterol as part of a standard diet with and without regular moderate physical activity on the main biomarkers of lipid and cholesterol metabolism, as well as the intestinal microbiota of male Wistar rats. The animals were randomly divided into 5 groups according to body weight and Open Field test results: Control (n=10), 1% Chol (n=10), 2% Chol (n=10), 1% Chol + RUN (n=10) and 2% Chol + RUN. The cholesterol was additionally added in the amount of 1g or 2g/100g, respectively, to the diet of animals. The rats of experimental groups 1% Chol + RUN and 2% Chol + RUN were subjected to regular (2 days a week) physical activity on a Treadmill. In rats of four experimental groups, when compared to the Control, a response of 39 indicators was revealed. The largest number of changes in biomarkers - 29 (statistically significant, p

Due to improper nutrition, high-density lipoproteins (HDLs) can be subjected to structural changes, acquiring a dysfunctional phenotype. Therefore, research efforts are currently focused on improving HDL functionality despite its blood level. The aim of this study was to evaluate the effect of phycocyanin concentrate (as part of a food matrix) on the functional properties of HDL. Male Wistar rats were fed a high-fat diet containing 2% cholesterol for 113 days. Experimental animals were treated with 30 and 300 mg/kg b.w. of phycocyanin concentrate mixed with soy protein isolate. Serum and hepatic cholesterol and triglyceride levels, and the content of protein, triglycerides, choline-containing phospholipids, malondialdehyde, sphingosine-1-phosphate, and paraoxonase-1 in HDL fractions were assessed. The decrease in protein in HDL particles is characteristic for dysfunctional phenotype of these particles. Phycocyanin concentrate diet prevented the depletion of protein in HDL particles, regardless of the dosage. The functionality of HDL is associated with paraoxonase-1 activity, which inhibits lipid peroxidation in lipoproteins. Our results have shown a significant increase in the level of paraoxonase-1 in HDL particles in groups treated with phycocyanin. HDL particles become more enriched with triglycerides with the development of hyperlipidemia. Triglycerides in HDL particles and in serum decreased by two times in animals receiving 30 mg/kg b.w. of phycocyanin. The MDA content in HDL particles decreased in all animals receiving a high-fat diet with the addition of 2% cholesterol. The introduction of 300 mg/kg of phycocyanin returned this indicator to the values of the Control group. Thus, biomarkers of dysfunctional changes in HDL in rodent hyperlipidemia models may be a useful tool for assessing lipid metabolism disorders. Also, the results confirm the potential ability to use phycocyanin concentrate as part of lipid-lowering products.