Amino Acid Composition of Food Proteins: Inter- and Intralaboratory Variation

1971 ◽  
Vol 54 (4) ◽  
pp. 777-781
Author(s):  
J E Knipfel ◽  
J R Aitken ◽  
D C Hill ◽  
B E McDonald ◽  
B D Owen

Abstract Inter- and intralaboratory variation in amino acid composition of casein, soy flour, and fish flour was examined for 5 cooperating laboratories, utilizing ion exchange chromatographic analyses for amino acids. Duplicate analyses within laboratories exhibited coefficients of variation of 3.7 to 4.4%. Hydrolysis was observed to affect amino acid recoveries to a significant degree, with some amino acids affected to greater extents than others. Laboratories utilizing Moore-Stein type analytical procedures did not appear to be more precise than those using the Piez-Morris method. Adjustment of data to constant total recovery values reduced interlaboratory variation considerably and suggested that recovery constants may be of value in comparing data from different laboratories. Results indicated that different laboratories employing varying analytical procedures may produce practically identical results from a standard sample, although variation may be observed due to characteristics of a specific system. Most variation in results was likely due to sample manipulations rather than to analysis per se.

2021 ◽  
Vol 4 (1) ◽  
pp. 56-72
Author(s):  
Mykhailo Peresichnyi ◽  
Svitlana Peresichna ◽  
Anna Sobko

The topicality. To date, the structure of the population’s diet has significant deviations from the formula of a balanced diet in terms of protein intake, including sulfur-containing, which causes the formation of risk factors for the development alimentary and alimentary-dependent diseases. For the prevention of diseases caused by protein deficiency, it is promising to increase its content in vegetable dishes due to the integrated use of raw materials and dietary supplements of high biological value. It is advisable to use food combinatorics in the innovative technologies development for vegetable dishes of improved amino acid composition. The purpose of the study is food combinatorics of amino acid composition of potato croquettes with soy flour, wheat germ; natural shrimp powder “Rieber Food Ingredients” and lentil-spirulina filling in terms of content and balance of essential and substitute amino acids and the degree of their assimilation by the human body. Research methods. Physicochemical, mathematical and statistical methods of experimental data processing with the use of information technologies, methods of ion exchange liquid column chromatography and qualimetric methods have been used. Results. Research is aimed at the use of food combinatorics and scientific substantiation of the amino acid composition of potato croquettes with the use of protein vegetable and non-fish water raw materials and dietary supplements. As a result of scientific researches the food combinatorics at development of technology of vegetable dishes has been carried out, the amino acid structure has been proved and experimentally generalized, the amino acid score and balance of sulfur-containing amino acids in the complex use of potato mass with wheat germ, soy flour, natural shrimp powder “Rieber Food Ingredients” and lentil-spirulina filling in culinary products have been analyzed. The social effect of fuller use of vegetable, non-fish water raw materials, expansion of the range of vegetable dishes with improved amino acid composition and consumer properties of potato dishes in restaurants, preservation and protection of public health has been confirmed. Conclusions and discussions. Food combinatorics was carried out during the potato croquet technology development with the use of protein vegetable and non-fish water raw materials, which contributed to the improvement of the amino acid composition of vegetable dishes and, in particular, to the increase of their biological value.


1980 ◽  
Vol 60 (4) ◽  
pp. 1327-1331 ◽  
Author(s):  
F. W. SOSULSKI ◽  
N. W. HOLT

Eleven grain legumes were analyzed for amino acids (AA), AA scores and essential AA indexes (EAAI). Nitrogen-to-protein (N:P) factors were determined from these data. Concentrations of AA per gram of nitrogen were relatively constant among species with the exception of the AA arginine, methionine, tryptophan and cystine which had coefficients of variation of 23–30%. On average, arginine, leucine, lysine, aspartic acid and glutamic acid accounted for 50% of the total of all AA. These grain legumes met adult human requirements for essential AA except for methionine and cystine which were deficient in all species. This resulted in an average AA score and EAAI of 56 and 89, respectively. The N:P factor was 5.6 for the 11 species but this value was 5.0 if corrected for nonprotein nitrogen.


1955 ◽  
Vol 8 (4) ◽  
pp. 537 ◽  
Author(s):  
DH Simmonds

The amino acid composition of 16-hr 6N HCI hydrolysates of three qualities of commercially classified wools has now been determined using the technique of Moore and Stein (1951). In this paper the results obtained on samples of Merino 70's and Corriedale 56's wool are compared with those previously reported for Merino wool of 64's quality. The overall pattern of the amino acid composition of the three wools is similar although small variations between the wools are observed with some of the amino acids.


1973 ◽  
Vol 134 (2) ◽  
pp. 431-436 ◽  
Author(s):  
W. Ferdinand ◽  
W. Bartley ◽  
V. Broomhead

Amino acid analyses of mitochondrial membranes are compared with the amino acid composition of whole mitochondria (Alberti, 1964) and found to be very similar except in the cystine content. The composition of the endogenous amino acids found in freshly prepared mitochondria has been established and shown to differ considerably from the amino acid composition of membranes or whole mitochondria. The amino acids produced during anaerobic incubation of mitochondria at pH7.4, on the other hand, resemble the membrane in composition, supporting the view that neutral proteinase activity is responsible for their appearance. Aerobic incubation produces a similar pattern of amino acids except that amino acids such as proline, serine, asparagine, glutamic acid and glutamine, which can be metabolically utilized under aerobic conditions, are present to a smaller extent. The presence of large relative concentrations of endogenous taurine, cysteic acid and oxidized glutathione and the accumulation of taurine during incubation is found. The selective retention of taurine and cysteic acid within the mitochondria is established. It is proposed that the first step in the degeneration of isolated mitochondria results from lipid hydroperoxide accumulation caused by the lack of glutathione reductase in isolated mitochondria.


1955 ◽  
Vol 102 (4) ◽  
pp. 435-440 ◽  
Author(s):  
Leonard T. Skeggs ◽  
Walton H. Marsh ◽  
Joseph R. Kahn ◽  
Norman P. Shumway

A preparation of hypertensin I was purified by countercurrent distribution and was shown to migrate as a single component in starch blocks at pH 9.3 and 4.2. It had an isoelectric point of 7.7. Quantitative analysis by ion exchange column chromatography showed eight amino acids in approximately unimolar proportion: aspartic, proline, valine, isoleucine, leucine, tyrosine, phenylalanine, and arginine. There were in addition two moles of histidine.


2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Karidia Konate ◽  
Emilie Josse ◽  
Milana Tasic ◽  
Karima Redjatti ◽  
Gudrun Aldrian ◽  
...  

AbstractRecently, we designed novel amphipathic cell-penetrating peptides, called WRAP, able to transfer efficiently siRNA molecules into cells. In order to gain more information about the relationship between amino acid composition, nanoparticle formation and cellular internalization of these peptides composed of only three amino acids (leucine, arginine and tryptophan), we performed a structure–activity relationship (SAR) study. First, we compared our WRAP1 and WRAP5 peptides with the C6M1 peptide also composed of the same three amino acids and showing similar behaviors in siRNA transfection. Afterwards, to further define the main determinants in the WRAP activity, we synthesized 13 new WRAP analogues harboring different modifications like the number and location of leucine and arginine residues, the relative location of tryptophan residues, as well as the role of the α-helix formation upon proline insertions within the native WRAP sequence. After having compared the ability of these peptides to form peptide-based nanoparticles (PBNs) using different biophysical methods and to induce a targeted gene silencing in cells, we established the main sequential requirements of the amino acid composition of the WRAP peptide. In addition, upon measuring the WRAP-based siRNA transfection ability into cells compared to several non-peptide transfection agents available on the markets, we confirmed that WRAP peptides induced an equivalent level of targeted gene silencing but in most of the cases with lower cell toxicity as clearly shown in clonogenic assays.


Author(s):  
С.Е. НИЗКИЙ ◽  
Г.А. КОДИРОВА ◽  
Г.В. КУБАНКОВА

Из 20 аминокислот, входящих в состав растительных белков, 17 лучше всего определяются с помощью высокоэффективной жидкостной хроматографии. Но эта технология затратна по времени, в том числе из-за подготовки проб, что делает ее малопригодной при проведении массовых анализов, например при оценке селекционного материала. В этом случае наиболее приемлемы технологии, основанные на сканировании в ближнем инфракрасном диапазоне излучения. Несмотря на то что ИК-сканеры способны по одному калибровочному уравнению выявлять большое количество компонентов, необходима постоянная коррекция при определении состава аминокислот и приведении его в процентное соотношение. В статье рассматриваются варианты создания калибровочных уравнений для расчета аминокислотного состава белков сои с помощью компьютерных программ (Nir 42, ISI), обеспечивающих работу ИК-сканеров типа NIR-4250 или FOSS NIRSystem 5000. Установлено, что при создании калибровочных уравнений содержание каждой аминокислоты наиболее корректно выражать в абсолютных единицах (г на 100 г белка), а не относительных (%). 17 of the 20 amino acids, included in the composition of plant proteins, are most effectively determined using liquid chromatography. The technology of high-performance liquid chromatography is to a certain extent costly in time, among other things because of sample preparation that makes it unsuitable for mass analysis, for example, when evaluating a breeding material. In this case, the technology based on scanning in the near infrared radiation band are the most acceptable. Despite the fact that IR scanners are able to determine a sufficiently large number of components on the basis of one calibration equation, a constant correction is required when determining the composition of amino acids and reducing it to a percentage ratio. The options for creating calibration equations for determining the amino acid composition of soybean proteins for computer programs (Nir 42, ISI), which provide the operation of IR scanners, such as NIR-4250 or FOSS NIRSystem 5000 are considered in the article. It was found that when creating calibration equations, it is most correct to set for each amino acid its mass content (g per 100 g of protein), and not the relative portion (in %).


Author(s):  
F.I. Vasilevich ◽  
V.M. Bachinskaya ◽  
Yu.V. Petrova

Экспериментальные исследования кормовых добавок Абиотоник и Чиктоник проводили на базе вивария кафедры эпизоотологии и организации ветеринарного дела, а ветеринарносанитарную экспертизу продуктов убоя цыплятбройлеров проводили на кафедре паразитологии и ветеринарносанитарной экспертизы ФГБОУ ВО МГАВМиБ МВА имени К.И. Скрябина и ФГБНУ ФНЦ ВИЭВ РАН, аминокислотный состав мяса перепелов в Государственном бюджетном учреждении Краснодарского края Кропоткинская краевая ветеринарная лаборатория . Из цыплят в суточном возрасте кросса Кобб500 было сформировано три группы по 10 голов в каждой две опытные и контрольная опытным группам выпаивали кормовые добавки из расчета 1 мл/кг живой массы птицы до 50 суток выращивания, убой птицы проводили на 56 сутки. Тушки птицы после 24х часов созревания в холодильной камере при температуре 4 С подвергали исследованиям по общепринятым методикам: ГОСТ Р 519442002. Мясо птицы. Методы органолептических показателей, температуры и массы ГОСТ 314702012. Мясо птицы, субпродукты и полуфабрикаты из мяса птицы. Методы органолептических и физикохимических исследований аминокислотный состав мяса исследовали согласно М 0438 2009. Корма, комбикорма и сырье для их производства. Методика измерений массовой доли аминокислот методом капиллярного электрофореза с использованием системы капиллярного электрофореза Капель. Применение кормовых добавок в дозе 1 мл/кг живой массы способствовало увеличению живой массы птицы при применении Абиотоника на 54,23, а при применении Чиктоника на 37,70 по отношению к контролю. Во всех исследуемых пробах количество ЛЖК находится в пределах нормы и составило: в 1й опытной 1,390,03 мг КОН, во 2й опытной 1,420,04 мг КОН и в контрольной группе 1,810,06 мг КОН, что говорит о свежести и доброкачественности мяса. Значение рН мяса цыплятбройлеров находилось в трех группах в пределах нормы и не превышало 6,0. По результатам проведенных исследований аминокислотного состава красной и белой мышечной ткани цыплятбройлеров было установлено, что применение кормовой добавки Абиотоник способствовало увеличению незаменимых аминокислот на 12,14 и на 22,84 соответственно, а заменимых на 8,11 и на 22,51 по отношению к контрольной группеExperimental studies of feed additives Abiotonik and Chiktonik were conducted on the basis of the vivarium of the Department of Epizootology and Organization of Veterinary, and the veterinarysanitary examination of the products of slaughter broiler chickens was carried out at the Department of Parasitology and VeterinarySanitary Expertise of FSBEI HE MGAVMiB MBA named after KI Scriabin and the FSBI of the Federal Research Center of the VIEW RAS, the amino acid composition of quail meat in the State budget institution of the Krasnodar Territory Kropotkinskaya regional veterinary laboratory. Three groups of 10 animals each were formed from chickens at the daily age of the Cobb500 crosscountry, the experimental groups were fed feed additives at the rate of 1 ml / kg of live weight of poultry for up to 50 days of cultivation, and poultry were slaughtered for 56 days. Poultry carcasses after 24 hours of maturation in a refrigerating chamber at a temperature of 4 C were subjected to research according to generally accepted methods: GOST R 519442002. Poultry meat Methods of organoleptic characteristics, temperature and mass GOST 314702012 Poultry meat, offal and semifinished products from poultry meat. Methods of organoleptic and physicochemical studies) Amino acid composition of meat was carried out according to M 04382009. Feed, feed and raw materials for their production. Methods of measuring the mass fraction of amino acids by capillary electrophoresis using the Cappel capillary electrophoresis system. The use of feed additives in a dose of 1 ml / kg of live weight contributed to an increase in live weight of the bird when using Abiotonics by 54.23, and when using Chictonics by 37.70 relative to the control. In all studied samples, the number of VFAs is within the normal range and amounted to 1.39 0.03 mg KOH in 1 experimental group, 1.42 0.04 mg KOH in 2 experimental groups and 1.81 0.06 in the control group. mg KOH, which speaks of the freshness and goodness of meat. The pH of broiler chicken meat was in three groups within the normal range and did not exceed 6.0. According to the results of studies of the amino acid composition of red and white muscle tissue of broiler chickens, it was found that the use of the feed additive Abiotonik contributed to an increase in essential amino acids by 12.14 and by 22.84, and by replaceable ones by 8.11 and by 22.51 relative to the control group.Экспериментальные исследования кормовых добавок Абиотоник и Чиктоник проводили на базе вивария кафедры эпизоотологии и организации ветеринарного дела, а ветеринарносанитарную экспертизу продуктов убоя цыплятбройлеров проводили на кафедре паразитологии и ветеринарносанитарной экспертизы ФГБОУ ВО МГАВМиБ МВА имени К.И. Скрябина и ФГБНУ ФНЦ ВИЭВ РАН, аминокислотный состав мяса перепелов в Государственном бюджетном учреждении Краснодарского края Кропоткинская краевая ветеринарная лаборатория . Из цыплят в суточном возрасте кросса Кобб500 было сформировано три группы по 10 голов в каждой две опытные и контрольная опытным группам выпаивали кормовые добавки из расчета 1 мл/кг живой массы птицы до 50 суток выращивания, убой птицы проводили на 56 сутки. Тушки птицы после 24х часов созревания в холодильной камере при температуре 4 С подвергали исследованиям по общепринятым методикам: ГОСТ Р 519442002. Мясо птицы. Методы органолептических показателей, температуры и массы ГОСТ 314702012. Мясо птицы, субпродукты и полуфабрикаты из мяса птицы. Методы органолептических и физикохимических исследований аминокислотный состав мяса исследовали согласно М 0438 2009. Корма, комбикорма и сырье для их производства. Методика измерений массовой доли аминокислот методом капиллярного электрофореза с использованием системы капиллярного электрофореза Капель. Применение кормовых добавок в дозе 1 мл/кг живой массы способствовало увеличению живой массы птицы при применении Абиотоника на 54,23, а при применении Чиктоника на 37,70 по отношению к контролю. Во всех исследуемых пробах количество ЛЖК находится в пределах нормы и составило: в 1й опытной 1,390,03 мг КОН, во 2й опытной 1,420,04 мг КОН и в контрольной группе 1,810,06 мг КОН, что говорит о свежести и доброкачественности мяса. Значение рН мяса цыплятбройлеров находилось в трех группах в пределах нормы и не превышало 6,0. По результатам проведенных исследований аминокислотного состава красной и белой мышечной ткани цыплятбройлеров было установлено, что применение кормовой добавки Абиотоник способствовало увеличению незаменимых


InterConf ◽  
2021 ◽  
pp. 363-369
Author(s):  
Nadira Turganbaeva ◽  
Dinara Isakova

The objective of this paper was to study the amino acid composition of donkey milk inhabiting the Kegety gorge of the Chui region. As well as human milk, donkey and mare’s milk is albumin; the amount of casein is 35-45%, while cow’s milk is casein milk with casein content over 75%. The peculiarity of albumin milk is a higher biological and nutritional value, due to better amino acid balance, high sugar content and the ability to form small, delicate flakes when souring. In terms of its properties, albumin milk is closest to human milk and is the best substitute for it. The obtained results showed that the quantitative content of 7 essential amino acids out of 8, such as lysine, phenylalanine, leucine, isoleucine, methionine, valine, threonine is relatively high compared to other amino acids. Despite the absence of tryptophan in donkey milk, the percentage of 8 essential amino acids in donkey milk protein exceeds that in mare and cow’s milk.


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