Association of genotypes of cows of the Kholmogory breed by beta-casein with milk productivity

The aim of the study is to identify the frequency of occurrence of various allelic variants and genotypes of beta-casein in cows of the Kholmogory breed and their relationship with dairy productivity. The tasks of the research are genotyping of cattle of the Kholmogory breed by the beta-casein locus and establishing its connection with qualitative and quantitative indicators of dairy productivity. As the objects for the research there were taken 150 cows of the 1st, 2nd and 3rd lactation. An allele-specific variant of the PCR method (AS-PCR) was used to identify A1 and A2 beta-casein. As the result it had been established that in the studied part of the herd, 23 % of animals had the A2A2 genotype, 43 % of animals had the A1A1 genotype and 34 % of animals had the A1A2 genotype. For 100 days of the first lactation, animals with A1A2 genotype showed the highest value in milk yield. Animals with A2A2 genotype for 305 days of lactation had the highest milk yield and the amount of milk protein, however, the difference was not statistically significant compared to the animals with A1A2 genotype. Genotype A1A1 has lower indicators by all the parameters studied, with a significant difference relative to genotypes A1A2 and A2A2. Thus, the study of CSN2 is a promising area of scientific research, and the results of the study of beta-casein genotypes can be used as a marker selection in improving the herds of the Kholmogory breed

Методика измерений массовой доли соевого ингибитора трипсина: особенности разработки и аттестации

   Modern industrialization increases the requirements for the accuracy of identifying allergens, especially those that have a negative impact – soy trypsin inhibitor (STI). Correct determination of the presence of STI in food products containing soybeans is key for product safety control and labeling. The authors set a goal to develop and certify a method for measuring the mass fraction of STI using an enzyme-linked immunosorbent assay – a technique that may increase the specificity of the method and avoid false-negative results.   The object of research was a method for analyzing food allergens – an enzyme-linked immunosorbent assay carried out with a set of reagents produced by XEMA LLC. In the process of developing the measurement method, the main methodological factors influencing the accuracy of the measurement results were optimized: sample weight, time of its extraction, time and speed of sample centrifugation, ratio of supernatant liquid to ELISA buffer, incubation temperature, interaction time of the allergen-antibody complex with the coloring agent, the wavelength for measuring absorbance, and the maximum time for measuring absorbance after introduction of the stop reagent.   The developed method was tested during an interlaboratory experiment with the participation of 5 laboratories. Metrological characteristics were established in accordance with RMG 61–2010. The proposed method was certified in accordance with the requirements of GOST R8.563-2009, No. 102–FZ. The method has a wide range of quantitative determination of the mass fraction of STI from 0.5 to 25.0 μg/kg (ppb) with a detection limit of 0.1 μg/kg (ppb) and a relative error of 40 %. Based on the results of the research, the Federal Information Fund for Ensuring the Uniformity of Measurements (FIF) registered a certified method for identifying and quantifying the content of non-infectious food allergens of plant protein origin in samples of all types of food products and objects related to the requirements for food products, swabs taken from working surfaces during production control using reagent kits for an enzyme-linked immunosorbent assay produced by XEMA LLC No. FR.1.31.2022.43884. The method is intended for use in testing laboratories involved in monitoring the quality and safety of manufactured products; it can be used to confirm product compliance with the mandatory requirements established in the Technical Regulations of the Customs Union TR CU022/2012.   Современная индустриализация повышает требования к точности определения аллергенов, особенно в отношении оказывающих негативное воздействие, среди них – соевый ингибитор трипсина (СИТ). Корректное определение наличия СИТ в пищевых продуктах, содержащих соевые бобы, является ключевым для контроля безопасности и маркировки продукции. Сложилась общепринятая практика определять аллергены сои количественно с помощью аналитических методов анализа. Авторы данной статьи поставили цель разработать и аттестовать методику измерений массовой доли СИТ методом иммуноферментного анализа – методику, способную повысить специфичность метода и избежать ложноотрицательных результатов ее применения.   Объектом исследования стал метод анализа пищевых аллергенов – иммуноферментный анализ, реализованный набором реагентов производства ООО «ХЕМА».   В процессе разработки методики измерений оптимизированы основные методические факторы, влияющие на точность результатов измерений: масса пробы, время ее экстракции, время и скорость центрифугирования пробы, соотношение надосадочной жидкости и ИФА-буфера, температура инкубации, время взаимодействия комплекса антитело-аллерген с окрашивающим агентом, длина волны для измерения оптической плотности и максимальное время для измерения оптической плотности после введения стоп-реагента. Разработанная методика апробирована в ходе межлабораторного эксперимента с участием 5 лабораторий. Метрологические характеристики установлены в соответствии с РМГ 61–2010. Предлагаемый метод был аттестован в соответствии с требованиями ГОСТ Р 8.563-2009, № 102–ФЗ. Метод имеет широкий диапазон количественного определения массовой доли СИТ от 0,5 до 25,0 мкг/кг (ppb) с пределом обнаружения 0,1 мкг/кг (ppb) и относительной погрешностью 40 %. По результатам проведенного исследования в Федеральном информационном фонде по обеспечению единства измерений (ФИФ) зарегистрирована аттестованная методика идентификации и количественного определения содержания неинфекционных пищевых аллергенов белкового растительного происхождения в пробах всех видов пищевых продуктов и объектов, связанных с требованиями к пищевой продукции, смывов, отбираемых с рабочих поверхностей при проведении производственного контроля, с помощью наборов реагентов для иммуноферментного анализа производства ООО «ХЕМА» № ФР.1.31.2022.43884. Методика предназначена для применения в испытательных лабораториях, занимающихся контролем качества и безопасности выпускаемой продукции, может быть использована для подтверждения соответствия продукции обязательным требованиям, установленным в Техническом регламенте Таможенного союза ТР ТС 022/2012

ELECTRONIC AND STRUCTURAL PARAMETERS OF PHOSPHORUS–OXYGEN BONDS IN INORGANIC PHOSPHATE CRYSTALS

Wide set of experimental results on binding energy of photoelectrons emitted from P 2p, P 2s, and O 1s core levels has been observed for inorganic phosphate crystals and the parameters were compared using energy differences Δ(O 1s - P 2p) and Δ (O 1s - P 2s) as most robust characteristics. Linear dependence of the binding energy difference on mean chemical bond length L(P–O) between phosphorus and oxygen atoms has been found. The functions are of the forms: Δ (O 1s - P 2p) (eV) = 375.54 + 0.146 · L(P–O) (pm) and Δ (O 1s - P 2s) (eV) = 320.77 + 0.129 · L(P–O) (pm). The dependencies are general for inorganic phosphates and may be used in quantitative component analysis of X-ray photoemission spectra of complex oxide compounds including functional groups with different coordination of P and O atoms.Phosphate, XPS, crystal structure, chemical bonding

The low thermal gradient Czochralski crystal growth and microstructural properties of a Pb2MoO5(20-1) cleaved surface

Optical quality Pb2MoO5 single crystals were grown by the Low Thermal Gradient Czochralski (LTG Cz) technique. The resulting Pb2MoO5 crystals had diameters of 40–50 mm and lengths of ~100 mm. The phase composition of the grown crystals was identified by X-ray single crystal structure analysis; the space group is C2/m and a = 14.2221(11), b = 5.7852(5), c = 7.3262(6) Å, β = 114.168(2)° and Z = 4 (R1 = 0.0336). Pb2MoO5(20−1) substrates were prepared by cleavage, and the surface properties were evaluated by RHEED and AFM. The superposition of wide Kikuchi lines and crystal reflexes was found by RHEED. The AFM measurements indicate a surface roughness as low as ~0.2 nm. Thus, atomically smooth surfaces of Pb2MoO5 were formed by cleavage

The low thermal gradient Czochralski crystal growth and microstructural properties of a Pb2MoO5(20-1) cleaved surface

Optical quality Pb2MoO5 single crystals were grown by the Low Thermal Gradient Czochralski (LTG Cz) technique. The resulting Pb2MoO5 crystals had diameters of 40–50 mm and lengths of ~100 mm. The phase composition of the grown crystals was identified by X-ray single crystal structure analysis; the space group is C2/m and a = 14.2221(11), b = 5.7852(5), c = 7.3262(6) Å, β = 114.168(2)° and Z = 4 (R1 = 0.0336). Pb2MoO5(20−1) substrates were prepared by cleavage, and the surface properties were evaluated by RHEED and AFM. The superposition of wide Kikuchi lines and crystal reflexes was found by RHEED. The AFM measurements indicate a surface roughness as low as ~0.2 nm. Thus, atomically smooth surfaces of Pb2MoO5 were formed by cleavage