[The comprehensive studies of Hermetia illucens larvae protein's biological value].

A high protein content in the insect biomass allows to classify this product as a very promising source of protein, comparable in nutritional and biological value with proteins of animal origin. Despite a long history of safe use, in some countries insects are considered a new type of food which safety must be proven before entering the food market. The long-term Russian experience in novel food's research allows to identify the crucial stages, among which, along with toxicological and allergological tests, the protein's biological value determination takes an important place. The conclusion about the biological value of protein is formed on the basis of integrated use of chemical and biological methods, which gist comes down to the study of the nitrogen balance in the growing organism (biological method) and the calculation of the amino acid score (chemical method). The aim of the research was the comprehensive assessment of Black soldier fly (Hermetia illucens) larvae protein's biological value using chemical and biological methods. Material and methods. Biological studies based on measuring of net protein ratio/net protein utilization were performed on 28 growing (between 25-50 days of life) male Wistar rats, with an initial body weight of ~65.5±1.2 g. Rats in the control group (n=14) received a semi-synthetic casein diet with a protein content of ~12% in calories, the test group (n=14) received a diet including an equivalent amount of H. illucens protein. The diet's ingredients were replaced with the consideration of the proteins, fats, and carbohydrates content in the included product following the principle of isocaloricity and isonitrogenicity (by mass fraction of total nitrogen). H. illucens biomass and casein in the test and control groups, respectively, were the main significant sources of nitrogen in the diet. Body weight, feed intake, and fecal and urine nitrogen losses were measured during the experiment. The biological value and digestibility of protein were judged by coefficients of protein efficiency ratio, net protein ratio, true protein digestibility, true protein biological value, true net protein utilization. Chemical studies included studies of the amino acid composition of H. illucens biomass protein and calculation of the digestible indispensable amino acid score (DIAAS). Results. The general condition of animals of the both groups during the whole experiment was satisfactory, the weekly body weight increase corresponded to the level of growth typical for Wistar rats, intergroup differences were not detected. Despite the fact that in a number of indicators the test group animals differed from the control [there were noted a decrease of the net protein ratio (by 5%, p>0.05), true protein digestibility (by 11%, p<0.05), net protein utilization (by 13%, p<0.05), caused by increased excretion of nitrogen with urine (by 8%, p>0.05) and feces (by 186%, p<0.05), with the same amount of nitrogen intake], the test rats' growth rate and the nitrogen's retention degree indicate a relatively high biological value of insect protein. According to the DIAAS, H. illucens protein is characterized by high content of histidine, threonine, valine, isoleucine and leucine (DIAAS=100 and more), and is also a source of sulfur-containing amino acids - methionine and cysteine (DIAAS=86) and lysine (DIAAS=97). Conclusion. The comprehensive studies of Hermetia illucens larvae protein's biological value demonstrated a high protein content, its balanced amino acid composition and high biological value, which allows to consider Hermetia illucens as a potential source of complete dietary protein.

Modification of vitamin-mineral diet composition as a model of adaptive potential reducing in laboratory animals.

This publication presents the results of research that was aimed at elaboration of adaptive potential reducing model, intended for toxicological experiments. Two series of research (with a duration of 70 days each) were conducted on Wistar rats. In the 1st series five groups of animals received diets with 100, 75,50,25 and 0% of vitamins B1, B2, B3, B6 and minerals(Fe3+ and Mg2+); in the 2nd series four groups of animals received diets with 21.37, 9.94, 4.62, 2.15% of this vitamins and minerals. In the 1st series of studies the intervals of maximum, medium and minimum content of essential nutrients in the diet was established; in the 2nd series the range of the lowest possible concentrations of these elements that provided the lowest level of adaptive potential and not causing the pathology development was determined. The certain set of hematological, biochemical, immunological and other indicators were investigated, this article analyzes the results of zoometric studies, mortality of animals, as well as the results of antioxidant status (activity of superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase and malondialdehyde content in red blood cells) studies. Based on the evaluation of the data which were obtained in the 1st series, it follows that a dose reduction of relevant essential nutrients to 25% didn't significantly affect the values of the studied indicators, and the complete elimination of these substances resulted in massive death of animals. In the 2nd series a significant differences between the groups were observed from the range of increased mortality (groups with 2.15 and 4.62% content of essential nutrients) to the range of deviations from central tendency of some parameters (group with 21.37% content). The data allowed to trace the dependence of these differences on the levels of vitamins and minerals in the diet. The results were used to determine threshold values of vitamins and minerals that provided the necessary reduction of the adaptive potential level in male and female rats. Taking into account the risk of pathology development, three dosages of essential substances have been established - optimal, marginal and submarginal, which provide consistent decline of adaptive potential of laboratory animals: 75, 30 and 19% for males and 75, 28 and 18% for females, respectively. The modification of vitamin and mineral composition of the diet can be used as a model of adaptive potential reduce in toxicological research.

Assessment of the impact of genetically modified LibertyLink® maize on reproductive function and progeny development of Wistar rats in three generations.

This publication presents the assessment of the impact of genetically modified (GM) LibertyLink® maize on reproductive function, prenatal and postnatal progeny development of Wistar rats over three generations. The animals were divided into two groups, which were fed with rodent diet with inclusion of GM LibertyLink® ('test' group) and non-GM near-isogenic counterpart ('control' group) maize varieties. The maize was included into the diet at maximum possible level (between 32 and 33%) not causing nutritional imbalance or metabolic disturbance for the experimental animals. Data analysis showed no impact of LibertyLink® maize on the animals' fertility: the observed mating efficiency in both groups was within the normal expected range values under the given experiment conditions. The comparison of progeny prenatal development in the generations F0-F2 has not shown any differences between the groups. Analysis of the physical development of the F0-F2 progeny or pups body weight and length progress did not show any abnormalities. The average number of pups per litter in the control and test groups was within the expected range of variations. Therefore, the results should be considered as direct evidence of the lack of any reproductive toxicity of LibertyLink® maize (a.k.a. T25 maize).

[Hematologic indices in different age wistar rats, receiving a balanced semi-synthetic vivary diet].

This paper presents the results of research of hematologic parameters of male Wistar rats 1, 2, 3, 4 and 6 months age, which received a balanced semisynthetic diet. Studies were carried out at the Hematology analyzer Coulter AC TTM 5 diff OV (Beckman Coulter, USA) with the program, specially developed for the study of rats' blood. According to the results of research, was found a statistically significant increased of the number of red blood cells; the concentration of hemoglobin and hematocrit in animals 2-6 months compared with rats, 1 month age. With age, there is a decrease of the mean corpuscular volume and the mean corpuscular hemoglobin. The number of white blood cells in rats of 2-4 months age are significantly higher than in rats of 1 and 6 months age. The number of neutrophils and eosinophils in rats of to the 2 month are of is lover than once in rats of 1 month age, and increases values in animals of 6 months age. The number of lymphocytes has the highest value in the rat of 2-3 months age and the minimum value is that in animals of 6 months age. With increasing of the age of the animals the reduction of contents of monocytes was noted. The content of platelets and the platelet crit in the blood of rats 6 months age is statistically greater than those in 1-month age animals. The average volume of platelet is the stable index, with age does not change.

[The separate and combined effects of calcium pantothenate deficiency and cadmium intoxication on rat reproductive function].

The publication presents investigation evaluated of separate and combined effects of calcium pantothenate deficiency and cadmium (Cd2+) intoxication on rat reproductive function. The experi-ments were performed on 280 adult and 890 offspring of Wistar rats. Reproductive function was estimated by fertility study, prenatal and postnatal development of offspring. The separate and combined effects of and cadmium intoxication during the mating period and pregnancy had no effect on fertility and fecundity of rats, pre-and postimplantation loss, the survival of offspring, and not caused the abnormal development of skeleton and internal organs. However, in prenatal ontogeny of this effect was manifested by lower body weight and fetal growth, postnatal - underdevelopment of rat pups in all morphological and functional studied parameters and increasing number of stillbirths in the offspring.

[Assessment of the impact of GMO of plant origin on rat progeny development in 3 generations].

The publication presents the results of assessment of impact of genetically modified (GM) maize Liberty Link on prenatal and postnatal development of progeny of 3 generations of Wistar rats. A total of 630 adult animals and 2837 pups were used in the experiment. The animals were divided into 5 groups which got the diets with inclusion of maize: the animals of the experimental group got the diet with the GM-maize, animals of the control group - with near isogenic conventional analogue of the GM-maize, animals of the 1st, 2nd and 3rd reference groups - conventional varieties of maize ROSS 144 MV, ROSS 197 MVW, Dokuchayevskaya 250 MV respectively. The maize was included in the diet at maximum possible level not violating the balance of basic nutrients. Analysis of the data obtained during the study did not reveal any impact of GM-maize on rat progeny development.

[A comparative effect of the experimental diet on growth and development of rats].

There are presented the results of a comparative assessment of the semi-synthetic casein diet, traditionally used by Institute of Nutrition RAMS, and the AIN-93 purified diet, offered by the American Institute of Nutrition, on growth and development of rats. A total of 60 male Wistar rats were used at 90-days experiment, rats were divided into two groups: first group received the semi-synthetic casein diet, the second group--AIN-93 diet. Analysis of integral, hematological and biochemical parameters revealed some differences between groups, but values of all studied parameters were within the physiological norm for Wistar rat. Based on the results of this experiment were suggested a new formulation of a diet for laboratory animals.

[Effect of genetically modified plants on the development of rat progeny].

The paper presents the results of evaluating the effect of genetically modified (GM) maize on the prenatal and postnatal development of rat progeny in three generations. An experiment used 280 adult rats (160 females and 120 males) and 1545 infant rats of the first month of life. The animals were divided into 2 groups: 1) those given a diet including GM maize (an experimental group); 2) those fed on its isogenic control (a control group). The maize was included into the diet in maximally possible amount that did not impair the balance of essential nutrients (31.4% caloric value). Analysis of the data obtained from studies of the prenatal (preimplantation and postimplantation death and fetal somatometric parameters) and postnatal (physical development, survival, changes in somatometric parameters) development of rat offspring revealed no effect of GM maize as compared to the isogenic control. All the parameters were in the normal physiological range typical of the animals of this species and age. Thus, dietary intake of the given amount of GM maize had no impact on rat progeny development.

[Medical and biological safety assessment of genetically modified soybean event MON 89788. Report 1. Toxicologo-hygienic examinations].

The results of toxicologo-hygienic examinations, which were conducted within the framework of integrated medical and biological assessment of genetically modified second generation soybean event MON 89788, are presented. Analysis of morphological, hematological, biochemical parameters and system (sensitive) biomarkers has not confirmed any toxic effect of soybean event MON 89788.

[Effect of carrageenan on indices of protein biological value and assimilability].

Influence of different levels of dietary carrageenan (0.2; 0.6, 2% with 18% casein) after 4 weeks in rats on coefficients of biological value (PER, NPR, NPUtr u BVtr) and digestibility (Dtr) of protein, microflore in cecum and morphometric data in distal part of small intestine were studied. There were found adverse changes of coefficients of biological value (NPUtr, BVtr) and digestibility (Dtr) after 2% dose of carrageenan. Chandes in microflore of cecum and worse of morphometric data in small intestine were observed.

[Methodical approaches to studying effect of seasonal factor on rat reproductive function in experiments on alimentary influence].

The results of studying influence of seasonal factor on rat reproductive system are presented. Function of reproductive system was estimated according sexual hormones in blood of pregnant rats, level of gametogenesis in female gonad, prenatal and postnatal development. The analysis of the data has not revealed correlation with climatic factors. Values of all studied parameters were in accord with the limits physiological norm and did not form obviously traced tendencies.

[The efficacy of enriching wheat meal, bread and gluten with L-lysine evaluated experimentally and theoretically]. / Effektivnost' obogashcheniia pshenichnoi muki, khleba i kleikoviny L-lizinom, opredeliaemaia éksperimental'no i teoreticheski.

The effect of enrichment of wheat meal, bread and gluten with L-lysine was studied by the routine method (basing on the biological value estimated on growing rats), and theoretically (by the changes in the potential extent of the biological value). A higher value of the enrichment effect in the second case has confirmed the existence of the compensation induced by significant lysine deficiency. Enrichment of the studied products with lysine leads to elimination of the compensation that consists in lysine economy through decreasing its oxidizing catabolism. The dependence of the biological value on the level of gluten protein in the ration was also studied. Maximum figures of the biological value were recorded at 15% of gluten protein level and they were decreased at 7 and 30% levels.