Accumulation of casein-derived peptides during growth of proteinase-positive strains of Lactococcus lactis in milk: their contribution to subsequent bacterial growth is impaired by their internal transport

2000 ◽  
Vol 67 (2) ◽  
pp. 233-240 ◽  
Author(s):  
CATHERINE FOUCAUD ◽  
VINCENT JUILLARD

To explain the limited nutritional value of milk cultured with proteinase-positive (Prt+) strains of Lactococcus lactis for the subsequent growth of dairy lactococci, we investigated further the time courses of modifications in the free amino acid and peptide contents of cultured milk. When growing in milk for up to 24 h, Prt+ strains of Lc. lactis progressively accumulated amino acids and casein-derived peptides. The growth of proteinase-negative (Prt−) wild-type strains and peptide transport mutants of Lc. lactis in cultured milk showed that casein-derived peptides could sustain growth up to 5×108 cfu/ml, depending on the extent of casein degradation during the preliminary growth of Prt+ strains and the Prt− strains. Of the casein-derived oligopeptides, <25% were transported into the cell and used for Lc. lactis growth. However, they played a prominent role, contributing 90% to growth. In contrast, di- and tripeptides did not contribute to growth, suggesting that either few were released from caseins or they did not supply essential amino acids.

2018 ◽  
Vol 115 (12) ◽  
pp. E2829-E2838 ◽  
Author(s):  
Farhan Abu ◽  
Justin G. Wang ◽  
Yangkyun Oh ◽  
Jingjing Deng ◽  
Thomas A. Neubert ◽  
...  

Sweet-insensitive Drosophila mutants are unable to readily identify sugar. In presence of wild-type (WT) flies, however, these mutant flies demonstrated a marked increase in their preference for nutritive sugar. Real-time recordings of starved WT flies revealed that these flies discharge a drop from their gut end after consuming nutritive sugars, but not nonnutritive sugars. We proposed that the drop may contain a molecule(s) named calorie-induced secreted factor (CIF), which serves as a signal to inform other flies about its nutritional value. Consistent with this, we observed a robust preference of flies for nutritive sugar containing CIF over nutritive sugar without CIF. Feeding appears to be a prerequisite for the release of CIF, given that fed flies did not produce it. Additionally, correlation analyses and pharmacological approaches suggest that the nutritional value, rather than the taste, of the consumed sugar correlates strongly with the amount (or intensity) of the released CIF. We observed that the release of this attractant signal requires the consumption of macronutrients, specifically nutritive sugars and l-enantiomer essential amino acids (l-eAAs), but it is negligibly released when flies are fed nonnutritive sugars, unnatural d-enantiomer essential amino acids (d-eAAs), fatty acids, alcohol, or salts. Finally, CIF (i) is not detected by the olfactory system, (ii) is not influenced by the sex of the fly, and (iii) is not limited to one species of Drosophila.


2016 ◽  
Vol 5 (10) ◽  
pp. 4972
Author(s):  
Lata Birlangi

The date palm (Phoenix dactylifera L.) is one of mankind’s oldest cultivated plants. The fruit of the date palm is an important crop of the hot arid and semi-arid regions of the world. It has always played a genuine economic and social part in the lives of the people of these areas. The present objective in examining the amino acid content of different varieties of date palm fruits from Middle-East region; is to determine whether its protein could effectively supplement the nutritional value and it is also aimed in finding which variety is rich in number of amino acids. The phytochemical screening revealed the presence of eight essential amino acids and five non-essential amino acids in the date fruits. Among all the date fruit varieties taken as samples for the study, Dabbas cultivar of United Arab Emirates found to exhibit eight types of amino acids which includes five as non-essential ones. Total of thirteen amino acids were detected in the seven date cultivars. Determination of amino acid can serve as a guide to the possible nutritional value.


Author(s):  
В.С. КУЦЕНКОВА ◽  
Н.В. НЕПОВИННЫХ ◽  
В.С. ГРИНЁВ ◽  
Е.В. ЛЮБУНЬ ◽  
А.А. ШИРОКОВ ◽  
...  

Исследованы показатели качества и пищевой ценности хлеба с добавкой цельносмолотых семян сафлора (ЦСС). Хлеб вырабатывали согласно ГОСТ 2784288 на основе муки пшеничной, дрожжей, воды, сахара, соли, но вносили ЦСС в сухом виде взамен 10 пшеничной муки. Установлено, что потребление 100 г обогащенных хлебобулочных изделий обеспечит удовлетворение суточной потребности, : в белке на 11 жире, содержащем повышенное количество полиненасыщенных жирных кислот, на 4,5 углеводах на 13 пищевых волокнах на 19 минеральных веществах на 1,59,5 витаминах группы В на 6,810,9 незаменимых аминокислотах на 218. Показано, что использование измельченных семян сафлора в рецептуре хлебобулочных изделий способствует повышению их пищевой ценности за счет внесения незаменимых полиненасыщенных жирных кислот омега3 (1), омега6 (28), омега9 (4,8). Энергетическая ценность готового изделия составляет 246,8 ккал (1031,6 кДж). Разработана рецептура хлеба повышенной пищевой ценности с добавкой ЦСС. Отработаны параметры процесса производства. Показано, что добавка нетрадиционного вида сырья цельносмолотых семян сафлора позволяет улучшить органолептические и физикохимические показатели хлеба, повысить его пищевую ценность. Indicators of quality and nutritional value of bread with the addition of wholeground safflower seeds were investigated. Bread is produced according to GOST 2784288 on the basis of wheat flour, yeast, water, sugar, salt, but with the addition of wholeground safflower seeds in dry form instead of 10 wheat flour. It was found that the consumption of 100 g of enriched bakery products will ensure the satisfaction of daily needs, : in protein for 11 fat containing an increased amount of polyunsaturated fatty acids, for 4,5 carbohydrates for 13 dietary fiber for 19 minerals for 1,59,5 vitamins of group B for 6,810,9 essential amino acids for 218. It is shown that the use of crushed safflower seeds in the formulation of bakery products increases their nutritional value by introducing essential polyunsaturated fatty acids omega3 (1), omega6 (28), omega9 (4,8). The energy value of the finished product is 246,8 kcal (1031,6 kJ). The formulation of high nutritional value bread with the addition of wholeground safflower seeds is developed. Parameters of the production process worked out. It is shown that the use of additives of nontraditional raw materials wholeground safflower seeds can improve the organoleptic and physicalchemical characteristics of bread, increase its nutritional value.


1971 ◽  
Vol 26 (9) ◽  
pp. 887-893 ◽  
Author(s):  
U. Zimmermann ◽  
G. Pilwat

An intracellular concentration of potassium in E. coli B 525 stationary for several hours is only attained by addition of the essential amino acids histidine and leucine, or ammonium chloride, to the incubation medium. The level of the stationary intracellular potassium concentration is dependent upon the concentration of these substances.The two other combinations of the essential amino acids (leucine/methionine and histidine/methionine) and the single amino acids show no stabilization effect upon the internal stationary potassium level.In the case of the wild type B 163, the instability of the stationary internal potassium concentration, and the corresponding effect of the above mentioned substances, is not so significant. Therefore the instability which is observed in the case of B 525 can be deduced from the mutation.


Author(s):  
C. B. Cowey ◽  
J. Adron ◽  
A. Blair

Present knowledge of the nutritional requirements of fish is limited to certain species of salmon and trout (e.g. Halver, DeLong & Mertz, 1957; Shanks, Gahimer & Halver, 1962). In view of the current interest in the cultivation of marine flatfish (Shelbourne, 1964) information on their dietary needs is equally desirable. Experience with salmon (DeLong, Halver & Mertz, 1958) has indicated that protein is the largest and most expensive constituent of fish diets and studies on the nutritional value of different food proteins for fish are necessary if the fish are to be reared economically and successfully. A desirable prerequisite to such studies is a knowledge of those amino acids for which the fish has an absolute dietary requirement, i.e. which it cannot itself synthesize from other substances normally available. With most animals these requirements have been identified by growth trials using partially (or wholly) defined diets. The rearing of fish on defined diets is not easy and it seemed in the first instance that an indirect but valid approach might be utilized. If animals are given a radioactively labelled carbon source, such as uniformly labelled [U-14C]glucose a significant amount of the radioactive carbon will be incorporated only into those compounds which the animal can itself synthesize. By isolating the amino acids from the tissue proteins following such a dose the essential amino acids are identified as those which are not radioactive. The amino acids containing radioactivity correspond with the so-called non-essential amino acids.


2018 ◽  
Vol 8 (1) ◽  
pp. 637-643
Author(s):  
T.L. Holubenko

<p><span lang="EN-US">The aim of the research is to assess the amino acid composition of veal from different genotype bull-calves concerning the usage in baby food production. A comparative analysis of the essential amino acids content in meat of calves of <span>black-and-white motley breed,</span> Aberdeen Angus breed and black and white crossbreeds grown according to the traditional technology of dairy cattle breeding hasn’t showed any significant differences. However, some differences were observed for each separate amino acid. Although the difference in amino acids was 2. 9% in favor of <span>black-and-white motley breed</span>. According to the amino acid composition, the calves meat of Charolais breed is biologically more complete than the Aberdeen Angus calves meat of the first generation in the valine content by 7.4%, isoleucine by 45.3% (P &lt;0.001), leucine by 15.2% (P &lt;0.001), lysine by 7.8%, threonine and phenylalanine + tyrosine by 6.5% (P &lt;0.05) and 7.5% (P &lt;0.01), respectively. Amino acid content was limited by the sum of amino acids phenylalanine + tyrosine (80.2%) in purebreds and methionine + cystine (83.4%) in <span>crossbreeds</span>. The other amino acids content was more than 100%; it indicates a high biological and nutritional value of veal. In the first experiment, the degree of compliance with the norms of a balanced diet is 37.4-38.2%. The human body's need for such essential amino acids as valine, isoleucine, phenylalanine + tyrosine is satisfied for more than 20%; the human body's need for leucine, lysine, and threoni9ne is satisfied for more than 30%. Veal of the Charolaise young is distinguished by higher indicators. The degree of its compliance with the norms of a balanced diet is 43.8% against 37.6% in hybrid calves. It is proved that veal obtained from young animals of different breeds in ecologically clean zones has a high biological and nutritional value, it corresponds to the indices for meat raw materials for baby food in accordance with Sanitary Norms 11-63 RB98.</span></p>


Author(s):  
T.V. Mazhaeva ◽  
S.E. Dubenko

To decrease the toxic effects of xenobiotics on healthy workers in healthful and dietary meals, it’s important to consider not only the proper diet intake of macro- and micronutrients, but protein quality in terms of essential amino acids. A study was conducted to evaluate nutritional value and amino acids content in the industrial workers diets of two metallurgical enterprises by calculation and laboratory methods. We found that set of healthful and dietary meals at the calculation stage do not comply with regulatory requirements for fats and carbohydrates by 34 and 16 percent, respectively. According to laboratory tests, from 57 to 68 percent of sets of healthful and dietary meals do not comply with regulatory requirements for proteins, fats and carbohydrates. The discrepancy in the data on the amount of determined nutrients between the calculated and laboratory methods may be due to calculation errors, shortage and quality of raw materials, as well as a limitation of methods for determining fat and carbohydrates. With a set of healthful and dietary meals workers can satisfy the almost daily requirement for the corresponding energy expenditures for some amino acids, however, the required amount of these amino acids in workers in contact with heavy metals has not been established. It has also been found that in diets of healthful and dietary meals, the ratio of tryptophan / lysine / methionine + cystine is violated towards an excess of tryptophan, whose deamination products are highly toxic. It is necessary to continue further investigation of ready-made diets of healthful and dietary meals for nutritional value and amino acid content in order to identify factors affecting the discrepancy within research results between calculation and laboratory methods, as well as establish adequate norms for amino acids intake in workers exposed to toxic substances.


Author(s):  
Tugay Ayasan ◽  
Mikail Baylan

The increasing costs of conventional feedstuffs like corn, soybean meal and fish meal for poultry diets is pushing the need to find less expensive alternatives. Mulberry grows well in the tropics and subtropics, and is reported to have excellent nutritional value. Mulberry leaves are very rich in protein (15-35%), minerals (2.42-4.71% Ca, 0.23-0.97% P), 1130-2240 kcal/kg metabolic energy (ME). The amino acids composition of mulberry leaf meal indicates it is a good source of essential amino acids especially lysine (1.80%) and leucine (2.58%). In this paper, studies made on the mulberry leaf used in nutrition of poultries have been reviewed.


10.5219/1657 ◽  
2021 ◽  
Vol 15 ◽  
pp. 846-857
Author(s):  
Hartati Kartikaningsih ◽  
Yahya Yahya ◽  
Trihartita Yuniar ◽  
Abdul Aziz Jaziri ◽  
Wahidu Zzaman ◽  
...  

The study aimed to evaluate the addition of banana blossom (12.5, 25, 37.5, and 50% w/w) on nutritional quality, histamine content, bacterial count, and sensory characteristic in the fish floss prepared from little tuna (Euthynnus affinis). The crude protein content, essential amino acids, lipid, and polyunsaturated fatty acids (PUFA) steadily decreased (p <0.05), while the crude fibre, carbohydrate, and ash components of the tuna floss, increased significantly (p <0.05) with increasing levels of banana blossom. The contents of protein, fat, ash, fibre, carbohydrate, and moisture ranged 28.13 – 30.27%, 14.79 – 18.02%, 4.45 – 5.68%, 2.6 – 3.5%, 27.81 – 31.01, and 16.45 – 17.39%, respectively, and most of them met the Indonesian National Standard. For essential and non-essential amino acids, the level varied about 102.82 mg.g-1 to 206.76 mg.g-1 and 79.71 mg.g-1 to 138.76 mg.g-1, respectively in the treated tuna flosses. Moreover, ranging 13.72 – 16.29% of PUFA was found in all treated flosses. The most significant effect was found in the histamine levels of the tuna flosses, especially in the 50% added floss sample. Moreover, bacterial counts and heavy metals content were lower than the maximum limits regulated by the Indonesian National Standard. For sensory evaluation, the banana blossom-added samples significantly increased (p >0.05) the acceptability score for all attributes assessed. Taken together, the tuna floss added with 37.5% of banana blossom may be potentially developed as a low-histamine tuna-based product with high ffibre andEPA+DHA, as well as highly acceptable for consumers.


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