Vitamin and antioxidant properties of tocopherols: characteristic of the molecular mechanisms of action
The molecular docking method was used to study the structural characteristics determining the competitive transport in the blood, and also the subsequent binding with enzymes of tocopherols and their metabolites to yield a specific biological activity. The target proteins were α-tocopherol-transport protein (α-TTP), tocopherol-associated protein 1 (TAP1), cyclooxygenase-2 (COX-2), protein phosphatase 2A (PP2A) and 3-hydroxy3-methylglutaryl-Coenzyme A (HMG-CoA) reductase. RRR-tocopherol (α-, β-, γand δ-forms), RRR-13’-carboxychromanol (α-, β-, γ- and δ-forms) and carboxyethyl hydroxychromanol (α-, β-, γ- and δ-forms) were used as ligands in this research. The conducted studies confirmed that among all homologues the α-tocopherol had the greatest affinity for the transport proteins α-TTP and TAP1 (ΔG=-11.40 and ΔG=-10.28 kcal/mol, respectively). It was shown that in all cases carboxyethyl hydroxychromanol metabolites had the greatest free binding energy (ΔG>-8 kcal/mol), that was why it has been concluded that they were not effective ligands for the proteins under study. In contrast, the metabolites of 13’-carboxychromanol, when bound to both α-TTP and TAP1 proteins, preferentially formed more stable complexes than their precursors. It was shown for the first time that γ-13’-carboxychromanol with TAP1 has less free binding energy (ΔG=-10.64 kcal/mol) in comparison to the α-tocopherol complex (ΔG=-10.28 kcal/mol). It has also been shown that 13’-carboxychromanole metabolites were more efficiently bound to COX-2 enzymes (ΔG=-9.56 kcal/mol for α-13’-carboxychromanol complex) and HMG-CoA reductase (ΔG=-9.46 kcal/mol for the complex with δ-13’-carboxychromanol). In relation to the PP2A protein, 13’-carboxychromanol metabolites had similar affinities as their precursors. The results of the work indicate the possibility of 13’-carboxychromanols to competitively bind to α-tocopherol transporters and act as effective ligands of COX-2 and HMG-CoA, that can be used to correct nutritional status in conditions accompanied by deficiency of tocopherols.
The study of the metabolism
of iodotyrosines included
in the iodized milk protein
In the course of evolution in animals and humans, a complex and effective system for providing the body with iodine in the form of various organic and inorganic compounds was developed. The metabolism of inorganic iodine has been studied quite well, in contrast to the mechanism of assimilation of its organic compounds. Among the latter, iodotyrosines, which are part of iodinated milk proteins, are of particular interest. To distinguish the peculiarities of the biotransformation of iodotyrosines in the animals' organism, their concentration and the concentration of tyrosine in blood plasma of rats after single administration of iodinated milk proteins were determined. For comparison, in parallel a group of animals received potassium iodide. The tested preparations were administered intragastrically with a probe in the form of aqueous solutions at a dose equivalent to 30 iodine per 1 kg of body weight. The level of mono - and diiodotyrosine in rat blood plasma was determined by HPLC with a mass spectrometer detector. The tyrosine content was determined on an automatic amino acid analyzer. The registration of the indices was carried out before the administration and 1, 4 and 24 hours after the administration of the substances. In the course of the conducted studies it was found that when iodinated milk proteins are once administered, a significant increase in the concentrations of monoiodotyrosine and diiodotyrosine is observed. The maximum level of iodinated amino acids, exceeding the control values by more than 6 fold, was recorded 4 hours after the ingestion of iodine-containing organic compounds into the body. At the same time interval, an increase in the concentration of tyrosine was observed in one of the experimental groups receiving iodinated milk protein. The simultaneous presence of tyrosine and its iodinated derivatives in blood plasma may indicate that monoiodotyrosine and diiodotyrosine are capable of being absorbed into the systemic bloodstream without metabolic transformations in the liver. Under introduction of potassium iodide, an increase in blood plasma concentration of monoiodotyrosine by 35% compared to the control was observed only after 24 hours, which may be a consequence of the activation of the thyroid gland due to the intake of an increased amount of iodine.
Yessotoxin: risk assessment for public health. Justification of regulations of content in seafood
Yessotoxin and its derivatives (about 90) are isolated from algae belonging to the species Protoceratium reticulatum, Gonyaulax cf. Spinifera, Lingulodinium polyedrum and from invertebrate organisms that feed on these algae. Previously yessotoxin have been associated with the group of diarrheal toxins. Later studies of the possible impact of yessotoxin on the activity of alkaline phosphatase allowed to exclude them from this group. Yessotoxin causes a violation of calcium entry in the cells, which, in turn, effects the calcium-calmodulin system and thus influences into homeostasis of the organism as a whole. It was shown that yessotoxin induces a biphasic change in the concentration of adenosine monophosphate, an initial increase with a subsequent relative decrease, within some minutes after adding the toxin to the lymphocytes cell culture. Yessotoxin has effects on immune system; which is manifested in an increase of cytokines level, by inducing the expression of the genes encoding them. Yessotoxin have impact into processes of cell adhesion via E-cadherin and, thus, could be an important factor in the development of Alzheimer's disease. It has been established that yessotoxin caused the development of apoptosis. In those cases all three mechanisms of cell death took place - apoptosis, paraptosis and autophagy. Yessotoxin's acute toxicity doses according to different data are from 100 to 500-750 μg per 1kg of body weight. Yessotoxin's acute reference dose (ARfD) - 25 μg/kg of body weight per day. The results of the analysis of yessotoxin level in shellfish meat showed that none of the studied samples contained more than 3.75 mg yessotoxin equivalents/kg shellfish meat. This level has been adopted by the European Union as the maximum acceptable level of yessotoxin in shellfish meat (EU Regulation N 786/2013). Presented data on the mechanism of action, toxicity and prevalence of yessotoxins make it necessary to establish regulations of their content in seafood, placed on the markets of the Eurasian Economic Union.
Features of actual nutrition of the adult population in Republic of Buryatia in modern conditions
Evaluation of the actual nutrition of the population of individual regions allows the development of targeted practical measures to improve nutrition, the structure of food consumption and appropriate recommendations to ensure optimal development and health status of a person. In order to study the nutrition of the adult population of the Republic of Buryatia, a retrospective analysis of the feeding structure data was conducted according to the data of the territorial department of the Federal State Statistics Service for the Republic of Buryatia, and the results obtained in the course of the questionnaire survey of 426 people (chosen by selective method with observance of representativeness) were analyzed. The data are presented obtained on the results of comparison with physiological needs in energy and nutrients for men and women in the most employable age of 30-39 years, having the third group of labor intensity. The structure of the food indicates its irrationality, which was confirmed by an increase in the consumption of food products with high content of saturated fats and added sugars, a decrease in the consumption of biologically valuable food products with high food density. In the product mix of the adult population of the republic, both among men and women, there was a lack of consumption of products from aquatic bioresources, vegetables, dairy products and eggs. At the same time, the consumption of bakery, flour-grinding products and potatoes in aggregate amounted to 120% of the recommended level. According to the results of the observation, 91.6% of the interviewed did not take into account the distribution of caloric intake by meals, in 5 0.8% the highest calorie intake was for dinner. Actual nutrition included elements that are risk factors for the development of endocrine pathology, disorders of the hormonal system and other metabolic diseases. There was a high level of energy intake for a number of years, which averaged 2891±43.6 kcal in men, 2407±38.4 in women, due to excess of fat and carbohydrates with a protein content of 82.4-87.3% of the recommended level. As a result, the problem of healthy nutrition, bringing the diet in line with the real physiological needs of a person requires serious systemic decisions in terms of organizing, systematizing and standardizing nutrition.
Actual liquid consumption by highly qualified athletes in the mode of the training
The purpose of the study was to evaluate the actual intake of fluids by athletes of various sports during the day with one and two training sessions before, during and after workout. The dietary intake, including consumption of various types of liquid foods and beverages, was evaluated by the method of 24-hour recall in 280 athletes of high qualification (candidates for masters and masters of sports) of both gender of various sports during the training period. It has been established that the main drink of rehydration was drinking bottled water. Bottled water was consumed on average by 86% of athletes. It was consumed by 95-96% of sportsmen from the group of single combats and power kinds, whereas in other groups the share of water consumers was less - 67- 79%. In secondplace in terms of percentage of consuming was tea. Consumption of sports drinks was observed only during training by athletes from the group of cyclic sports (31%) and single combat (11%). Calculating the per capita fluid intake of athletes who had 2 workouts a day showed that athletes from the martial arts group consumed the largest volumes of fluid in the mode of both training sessions as compared to representatives of other sports. Athletes of other sports consumed on average less liquid in the 2nd training mode compared to the 1st one. The total fluid intake during two training sessions was maximum in the group of martial arts and was minimum in the group of complex coordination sports. It should be specially noted a small proportion of athletes who consumed specialized sports drinks -only 17% of athletes and more than half of them - cyclical sportsmen. Consumption of liquid food outside training has been observed in 76% of athletes. The mean volume of consumed liquid products varied by the user from 382 and 437 ml in complex coordination and game sports up to 504-553 ml in other sports. The daily fluid intake was maximum (2326 ml) in athletes engaged in martial arts, minimum (1009 ml) - in athletes of complex coordination sports.
Using of specialized food for the workers with skin occupational eczema of perlite production
The research was conducted with participation of the perlite production workers with professional eczema (165 people in the main group and 152 from the control group without skin pathology). The effectiveness of the use of a specialized prophylactic food in the diet of workers was assessed on the basis of the study of the dynamics of the indicators of nutritional and clinical status. Inclusion of kissel, containing pectin, vitamin A (300% from RDA), vitamin E and zinc (40% from RDA), biologically active substances of plant origin in the diet of the examined against the background of the course of complex therapy, has resulted in a positive influence on individual laboratory values, demonstrating the optimization of metabolic processes, which characterize the pathogenesis of skin inflammation. Thus, the concentration of ascorbic acid in blood serum statistically significant (p<0.05) increased by 30.0%, tocopherol - by 36.3%, carotenoids -by 27.3%, phosphorus - by 28.9%, calcium level elevated by 16.3% (p<0.10). There was a decrease in the level of MDA in blood serum by 12.3% (p<0.05) and an increase in catalase activity by 12.2% (p>0.05). There was a tendency to reduce itching, infiltration, erythematous and eczematous manifestations of the disease. The data obtained make it possible to consider the use of a specialized food product of dietary preventive nutrition by workers inpearliteproduction as a mean to enhance the body's adaptive reserves and to prevent the occurrence, progression and development of occupational skin diseases (eczema) in the workplace.
Development of a meat-based product for enteral nutrition
Meat is a source of the most full value protein, which contains all essential amino acids, B group vitamins, minerals, including heme iron and zinc. The development of enteral mixtures produced on the basis of meat raw materials will allow leveling the problem of annoyance with the same product taste and extending an assortment of the supplied products for enteral nutrition. As a result of the experiments on the model and natural objects, the technology was developed for beef-based canned food intended for enteral nutrition of people in the post-operative period as well as in the conditions associated with appetite loss, mandibulofacial injuries, burning injury, chewing and swallowing impairments. The multi-component recipe modules balanced by fatty acid and amino acid composition, enriched with the vitamins and minerals were theoretically substantiated and realized. The minimal score was 0.99 unit fractions, coefficient of utility (0.83 unit fractions), coefficient of comparable redundancy 7.20 g/100 g protein. The obtained values of the balance criteria allow making a conclusion about approximation of the values to the physiologically necessary ratio. The correction of the fatty acid composition of the mixture models was carried out in order to increase the unsaturated fatty acid content by combination of meat fat with vegetable oils. The actual ratio of the fatty acid (SFA:MUFA:PUFA) in the product was 16.1:54.7:29.2, the ratio of omega-6 to omega-3 PUFA was 4:1. When designing the vitamin and mineral composition, the intensity of the thermal effect was taken into account. As a result, the doses for addition of vitamins were established with regard to their destruction during the technological process. Based on the performed research, the technology was developed for meat-containing canned food, adapted to the real conditions of the enterprises engaged in production of meat products for child nutrition. The product can be used as a basis or additional source of nutrition during the necessary period of nutritive support of patients.
Infant feeding in the rural
area of Chuvash Republic
and Nizhny Novgorod Region
The nature of feeding in the first year of life affects the health of the child in all subsequent periods of life. Objective - the article is devoted to the study of the state of feeding the children of the first year of life living in rural areas. The study was carried out on the basis of three children's clinics in the Chuvash Republic and the Nizhny Novgorod region by random sampling using an anonymous questionnaire of women who had children aged 1 to 2 years living in the rural areas of the Chuvash Republic and the Nizhny Novgorod Region (140 and 60 women, respectively). According to our data, the absolute majority of women surveyed (96%) wished to feed their babies for at least 1 year. All infants (100%) after birth were attached to the chest, in the first 30 minutes -62%, in later terms - 38%. Feeding the artificial formulas before the first application to the breast was used in nutrition of 26% of newborns. Exclusive breastfeeding for less than 4 months received 23% of babies, 4-6 months - 69%, 7 months - 8% of babies. The main reason for transferring infants to mixed and artificial feeding was hypogalactia. At the age of up to 6 months for mixed feeding 49% of babies were transferred, for artificial feeding - 16%. In most cases (69%), when signs of hypogalactia appeared no weighting was carried out, an independent transfer of the child to another type of feeding was observed in the same majority (65%) of cases. The choice of the mixture was carried out by the parents independently in 65% of cases, in other cases - on the recommendation of the pediatrician. In general, in most cases (66%), adapted mixtures were used in feeding the infants, cow milk (22%), goat milk (6%), and sour milk drinks (6%) were used from unadapted products. Before the age of 3 months 5% of babies completed breastfeeding, in the age of 4-6 months - 11%, 7-9 months - 16%, 10-12 months - 5%, more than 6 months continued to be fed with breast milk 84% of babies, more than a year - 63%. The average duration of breastfeeding was 13.8±4.2 months. Half (48%) of children received vegetable puree as the first supplement, in the remaining children porridge (24%), fruit puree (20%), cottage cheese (8%) served as such. Conclusion: breastfeeding of infants in rural areas needs active support from pediatric staff.
Evaluation of antioxidant
activity of fresh apples
different pomological varieties
after treatment with ionizing
Introduction to action GOST 33302-2015 "Fresh agricultural products. Guidance for irradiation as a phytosanitary treatment" on the territory of the Russian Federation regulating the use of radiation processing to extend shelf life and improve storability of fresh agricultural products requires commodity market understanding - to what extent and under what conditions this technology will allow you to keep the nutritional value of agricultural raw materials and meet the safety requirements in accordance with the Technical regulations of the Customs Union 021/2011 "On food safety". Currently there is no science-based regulation of radiation doses that would allow you to preserve the nutritional value of products, including antioxidant activity. Apples are the most accessible and widely distributed representative of fruit products in the consumer market of the country, characterized by a high content of antioxidants. The experimental material was investigated by a retrospective method. To confirm the fact of irradiation/non-irradiation, control samples of apples of different pomologic varieties ("Pink Lady", "Granny Smith", "Golden Delicess", "Gloster") were identified on the consumer market using electron paramagnetic resonance (EPR). The results of the study confirm that antioxidant content is due to the pomological belonging to a particular class and structure of the fruit (pulp or juice without pulp). The antioxidant activity (AOA) of freshly squeezed (untreated) juices, in contrast to the AOA of apples have lower rates and is lower for pomological variety "Pink lady" by 13.8%, for grade "Granny Smith" - by 22.0%, for the variety "Golden delicious" by 22.6% for class "Gloucester" by 23.0%, respectively. Studies have been conducted on the effect of various doses of ionizing radiation on antioxidant activity of fresh apples by potentiometric method using the K3[Fe(CN6)]/K4[Fe(CN6)] mediator system. Test samples of fresh apples were treated with ionizing radiation using a linear accelerator of electrons in doses from 1 to 12 kGy. AOA of experimental samples of fresh apples of pomological variety "Pink Lady" after irradiation with a dose of 12 kGy decreased by 4.5 fold compared with unirradiated samples, in apple varieties "Granny Smith" - by 2.9 fold, "Golden delishes" and "Gloucester" - by 3.1 fold, respectively. With an increase in irradiation dose of more than 3 kGy, the most intense decrease in antioxidant content occurs. A high correlation coefficient between the dose of irradiation and the content of antioxidants in the experimental samples of fresh apples of different pomologic varieties has been established - from 0.94 to 0.99. The obtained experimental data allow us to propose a limitation of the radiation dose to 3 kGy in order to preserve the antioxidant potential of fresh apples.
Scientific bases of development of frozen dessert
Berries of a honeysuckle are valuable raw materials which contain biologically active substances and can be used for production of foodstuff. A research objective was the development of sorbet with the use of honeysuckle berries in fresh and frozen state. It has been established that for product stabilization it was necessary to add an agar (1.6% to the mass of mix) and starch syrup (55 g per 1 kg of mass of mix). On the basis of results of the conducted researches the compounding has been proved and the technology of the frozen dessert (sorbet) from fresh and frozen honeysuckle berries has been developed. The content of vitamin C and flavonoids has been investigated. The content of vitamin C in sorbet from fresh berries was 62.5 mg/100 g, and from frozen ones - 52 mg/100 g. Content of flavonoids in a dessert received 850 mg per 100 g that allowed to recommend a product for the mass consumer and also people who have excluded milk and dairy products from the ration. Microbiological indicators of the developed sorbet didn't exceed threshold value both after preparation, and throughout the entire period of storage (72 h).
Investigation of lignans and anthocyanins as the main biologically active polyphenols of Schizandra chinensis fruits
For the first time the content and composition of dibenzocyclooctadiene lignans and anthocyanins in 10 samples of Chinese magnolia-vine fruits (Schizandra chinensis) collected in the Moscow Region, Khabarovsk and Primorsky Krai were studied. The determination of the profile of lignans was carried out according to the our original HPLC technique with diode-array spectrophotometric and mass spectrometric detection. The validation of the methodology for linearity, accuracy and precision was carried out. 11 characteristic for Schizandra chinensis lignans were found in all samples. In dried fruits the main lignan was schisandrine, in fresh-frozen fruits - angeloylgomizin O. The total content of lignans in fresh-frozen fruits was 5.50 mg/g, in dried fruits - from 12.50 to 18.95 mg/g. Anthocyanins of Chinese magnolia-vine were mainly represented by cyanidin glycosides, among which cyanidin-3-xylosylrutinoside was predominated. The total content of anthocyanins determined by pH-differential spectrophotometry was from 0.21 mg/g in fresh-frozen fruits to 0.35-0.72 mg/g in dried fruits. The results obtained can be used to identify and standardize the fruits of Chinese magnolia- vine and the products of their processing.