Arginine Content Research Articles

Black Soldier Fly Larvae Meal in the Diet of Gilthead Sea Bream: Effect on Chemical and Microbiological Quality of Filets.

The chemical and microbiological characteristics of filets of Spaurus aurata L. specimens fed with diets containing a Hermetia illucens meal (HIM) at the 25, 35, and 50%, as a partial replacement for fish meal (FM) were evaluated. The diets, formulated to satisfy the nutritional needs of fish, were isoenergetic (22 MJ/kg gross energy), isonitrogenous (43 g/100 g, a.f.), and isolipidic (19 g/100 g, a.f.). Seventy-two specimens were randomly killed after 186 days of growing trials. Then, the filets were analyzed for chemical profile, fatty acids, amino acids, minerals, and microbial flora. Data were subjected to statistical analysis. No significant differences were observed in chemical composition. The sum of polyunsaturated fatty acids (PUFAs) showed a similar content in the filets; eicosapentaenoic acid was similar in the filets of HIM0, HIM35%, and HIM50%, whereas docosahexaenoic acid was higher in filets of the HIM0 group. n3/n6 PUFA ratio and the sum of EPA + DHA showed a high value (p < 0.001) in filets of the group fed with FM. No significant difference was observed in thrombogenic index and hypocholesterolaemic/hypercholesterolaemic ratio in the groups; the atherogenic index showed a higher value (p = 0.001) in the HIM50% group. Indispensable amino acids showed some significant (p < 0.0001) differences in the groups; arginine and phenylalanine content was higher in the filets of fish fed with FM; isoleucine and valine content was higher in the filets of HIM50%; leucine, lysine and methionine content was lower in the filets of HIM35%; histidine content was lower in the filets of HIM25%; tryptophan content was lower in filets of the HIM50% group. EAA/NEAA ratio showed highest value in the filets of the group that received FM. The presence of HIM in the three diets kept chromium, manganese, iron, copper, zinc, and nickel levels lower than those recommended by various authorities. Ca/P ratio showed a higher level (p < 0.0001) in the group fed with FM than those fed with diets containing HIM. The insect meal in the diets did not influence the microbiological profile of fish. Use of HIM as an unconventional feed ingredient in Sparus aurata diet looks promising, although the quality of filets may be affected.

GABA keeps nitric oxide in balance by regulating GSNOR to enhance disease resistance of harvested tomato against Botrytis cinerea

Gamma-aminobutyric acid (GABA), a widely distributed metabolite in prokaryotes and eukaryotes, has many functions for plants in stress responses. In this study, hypotonic treatment with 10 mmol L−1 GABA in cherry tomato induced resistance to Botrytis cinerea with markedly lower disease incidence and lesion diameter, led to endogenous nitric oxide (NO) tansient accumulation before inoculation the pathogen then decrease after inoculation, and enhanced the content of arginine (Arg) and glutamic acid (Glu). The resistance of fruit treated with a NO scavenger, carboxy-2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO), was significantly reduced. Moreover, the enzyme activity and gene expression of S-nitrosoglutathione reductase (GSNOR) were enhanced following endogenous NO increased. The endogenous NO level was excessively high after treatment with a GSNOR scavenger, N6022, making the fruit more susceptible to pathogen. Similarly, after break down of SlGSNOR, fruit had much higher endogenous NO and lower disease resistance. However, overexpression of SlGSNOR exhibited opposite consequences. These results suggest that a suitable level of NO is beneficial for enhancing disease resistance, and GABA can help tomatoes maintain NO equilibrium by regulating GSNOR.

Guanidinium-Functionalized Flexible Azaproline Transporter for Efficient Intracellular Delivery of Proapoptotic Peptide and PDL1 Antisense Morpholino Oligo in Human Carcinoma Cells In Vitro.

Cell-penetrating peptides (CPPs) are structurally diverse sophisticated tools endowed with high arginine content, amphipathicity, and well-adopted suitable secondary structures. Despite its capability of breaching the lipid barriers, CPP has major limitations such as in vivo metabolic instability, poor bioavailability, and reduced endosomal escape tendency, which are yet to be improved. In this context, we first have introduced a new class of cellular transporter having a guanidinium-functionalized δ-azaproline (δ-azp)-containing peptide where the δ-azp structurally resembles the "proline" amino acid having an additional "N" at the δ-position. This non-natural peptidic backbone was found to impart proteolytic stability, as reported earlier by our group. Herein, we report the synthesis of a flexible azaproline-tetraguanidinium transporter named FAT along with a revised scalable methodology for δ-azp compared to our previously reported procedure. FAT shows a random-coil-like structure as determined by CD spectroscopy, and is hence structurally different from the polyproline PPII helix. Direct translocation is predicted to be the possible mode of the cellular entrance of FAT into CHO cells when the "Bodipy" fluorophore is covalently attached as the cargo. Simultaneously, two other macromolecular therapeutics, e.g., proapoptotic domain peptide (PAD, a 14-mer peptide) and programmed death ligand 1 (PDL1) morpholino (a 25-mer antisense oligo), were successfully conjugated with FAT and delivered into human carcinoma cells, and their efficacy was analyzed by MTT assay and western blot technique, respectively. Having obtained promising results in internalizing different types of cargos, FAT could be envisaged as a potential drug delivery agent as an alternative to natural CPPs for future application.

Role of the Transcriptional Regulator ArgR in the Connection between Arginine Metabolism and c-di-GMP Signaling in Pseudomonas putida.

The second messenger cyclic di-GMP (c-di-GMP) is a key molecule that controls different physiological and behavioral processes in many bacteria, including motile-to-sessile lifestyle transitions. Although the external stimuli that modulate cellular c-di-GMP contents are not fully characterized, there is growing evidence that certain amino acids act as environmental cues for c-di-GMP turnover. In the plant-beneficial bacterium Pseudomonas putida KT2440, both arginine biosynthesis and uptake influence second messenger contents and the associated phenotypes. To further understand this connection, we have analyzed the role of ArgR, which in different bacteria is the master transcriptional regulator of arginine metabolism but had not been characterized in P. putida. The results show that ArgR controls arginine biosynthesis and transport, and an argR-null mutant grows poorly with arginine as the sole carbon or nitrogen source and also displays increased biofilm formation and reduced surface motility. Modulation of c-di-GMP levels by exogenous arginine requires ArgR. The expression of certain biofilm matrix components, namely, the adhesin LapF and the exopolysaccharide Pea, as well as the diguanylate cyclase CfcR is influenced by ArgR, likely through the alternative sigma factor RpoS. Our data indicate the existence of a regulatory feedback loop between ArgR and c-di-GMP mediated by FleQ. IMPORTANCE Identifying the molecular mechanisms by which metabolic and environmental signals influence the turnover of the second messenger c-di-GMP is key to understanding the regulation of bacterial lifestyles. The results presented here point at the transcriptional regulator ArgR as a central node linking arginine metabolism and c-di-GMP signaling and indicate the existence of a complex balancing mechanism that connects cellular arginine contents and second messenger levels, ultimately controlling the lifestyles of Pseudomonas putida.

Nitrogen and Boron Dosage Effects on Arginine Accumulation in Scots Pine Needles

Free arginine (Arg) content was observed to multiply when the level of nitrogen (N) nutrition was high, and additional fertilization with boron (B) potentiated this effect. Owing to this feature, conifers can be suggested for use as bioproducers of Arg. Concentrations of Arg in relation to N and B fertilization needed to be better understood. The effect of soil fertilization with N and B on accumulation of these elements and free Arg in one-year-old needles of 16-year-old Scots pine (Pinus sylvestris L.) trees was determined in this study. Plantations were fertilized with doses of N from 0 to 1000 kg ha−1 and B from 0 to 6 kg ha−1. Fertilization with 3 kg ha−1 B at N doses of 200–500 kg ha−1 stimulated the accumulation of N in needles of up to 3.1–3.6% dry weight (DW). The level of Arg in needles increased from 74.7 to 175.9 μmol g−1 DW at these levels of N and B.

Breeding of ‘DND358’: A new soybean cultivar for processing soy protein isolate with a hypocholesterolemic effect similar to that of fenofibrate

• ‘DND358’ is ideal raw soy material for producing hypocholesterolemic SPI powder. • Modify protein subunit compositions is useful strategy for hypocholesterolemic soy breeding. • DND358-SPI: a superior diet-therapy soy beverage to achieve cholesterol homeostasis. • Enrich α′ subunit of 7S can be strategized in hypocholesterolemic soybean breeding. Soy proteins have hypocholesterolemic effects (HCE). Here, we developed a soybean cultivar ‘DND358’, which is superior for processing hypocholesterolemic soy protein isolate beverage powder (DND358-SPI). ‘DND358’ carries four recessive null alleles for the α subunit of 7S globulin and the G1, G2, and G4 subunits of 11S globulin (tetra null), was selected from a population derived from a three-way cross. The tetra null mutation resulted in a compensatory increase in the α′ subunit level and arginine content. The oral administration (300 mg/kg/day) of DND358-SPI processed from ‘DND358’ significantly decreased the fatty liver symptoms and hepatic lipid accumulation; reduced the hepatic total cholesterol (TC), triacylglycerol (TG) levels and atherogenic index (AI) value, in rats fed a high-cholesterol diet. Conversely, DND358-SPI administration markedly elevated high-density lipoprotein cholesterol levels, to values significantly higher to those fed on fenofibrate (FF, 30 mg/kg/day), a hypocholesterolemic drug. The HCE of DND358-SPI were similar to that of FF.

Effects of Dietary Arginine on Growth Performance, Digestion, Absorption Ability, Antioxidant Capability, Gene Expression of Intestinal Protein Synthesis, and Inflammation-Related Genes of Triploid Juvenile Oncorhynchus mykiss Fed a Low-Fishmeal Diet

In this study, the effects of arginine on growth, serum antioxidant levels, intestinal digestion physiology, intestinal protein synthesis, and expression of inflammatory-related genes of triploid juvenile rainbow trout (Oncorhynchus mykiss) were investigated. Five diets containing 0.86%, 1.65%, 2.10%, 2.85%, and 3.50% arginine were fed to satiation to triplicate groups of 30 fish per tank for 8 weeks. The results showed that the weight gain rate, specific growth rate, and protein efficiency ratio significantly increased. The optimal dietary arginine requirement was 2.48% (5.97% of dietary protein) based on quadratic regression analysis between specific growth rate and dietary arginine content. There were no significant differences in crude lipid and ash content. Moisture significantly decreased, and crude protein content significantly increased ( P &lt; 0.05 ). Superoxide dismutase, catalase, and lysozyme levels in serum and the liver first significantly increased and then decreased with the level of arginine compared to the control group ( P &lt; 0.05 ), while the malondialdehyde level significantly decreased. Intestinal lipase and amylase levels significantly increased, but there was no significant difference in trypsin level ( P &gt; 0.05 ). The muscular layer thickness and villus width foregut in the 2.85% group were significantly increased. TOR at 2.86% and IGF-1 and S6K1 at 2.11% reached the maximum level, and IL-1β, IL-6, and IL-8 showed a decreasing trend with their lowest levels in the 3.50% and 2.85% groups. The expression of TNF-α first decreased and then increased with the arginine level. Both TGF-β and IL-10 expression first decreased and then increased with the level of arginine and reached the maximum value in the 2.85% group. NF-κB showed an opposite trend and reached the lowest value in the 3.50% group. In conclusion, dietary arginine has a significant effect on growth, serum antioxidant capability, digestion physiology, immunity, digestion, and absorption of nutrients in triploid O. mykiss, and the optimum requirement is 2.48% fed a low-fishmeal diet.

Correlation between the microbial community and ethyl carbamate generated during Huzhou rice wine fermentation

Ethyl carbamate (EC) is a potential carcinogen that is mainly produced by the spontaneous reaction between urea and ethanol during rice wine brewing. Huzhou rice wine (HZRW) is a traditional Chinese rice wine, but the correlation between its urea content and the microbial communities present during the fermentation process has not yet been evaluated. In this study, high-throughput sequencing technology was used to monitor the microbial community composition of HZRW in the different fermentation stages. The correlations between the microbial community and the physical and chemical properties and EC, urea and arginine contents were evaluated using the redundancy analysis (RDA) method. The metabolic profiles of key genes in the arginine and urea metabolic pathways were obtained via phylogenetic investigation of the communities by reconstruction of unobserved states (PICRUSt). The results showed that the fungal genera Saccharomyces, Issatchenkia, Torulaspora and Rhizopus were dominant during the fermentation of HZRW. Weissella and Acinetobacter were the dominant bacterial genera in the early stage, while Weissella, Staphylococcus, Leuconostoc and Streptophyta were the dominant bacterial genera in the late stage. Urea and arginine were positively correlated with Saccharomyces, Lactobacillus and Staphylococcus. In addition, the dominant genera of both fungi and bacteria were involved in the metabolism of arginine and urea. Finally, the relationships between the dominant microorganisms and key genes of the arginine and urea metabolic pathways were established. The obtained results are helpful in better understanding the mechanisms of metabolism of arginine and urea during rice wine fermentation and therefore improving the safety profile of rice wine.

Rheum officinale Baill. Treats zebrafish embryo thrombosis by regulating NOS3 expression in the arginine biosynthesis pathway

BackgroundRheum officinale Baill. (ROB), as one of the traditional Chinese medicines for promoting blood circulation and removing blood stasis, has a wide range of pharmacological effects, such as cardiovascular protection, and has become a common drug in the clinical care of thrombosis. ObjectiveAlthough there are some pharmacological studies on ROB in the treatment of thrombotic diseases, the mechanism and material basis are still unclear. Based on the arginine biosynthesis signalling pathway, this research explored the target proteins and metabolites related to the intervention of ROB in thrombosis and expounded on the antithrombotic mechanism of ROB from the comprehensive perspectives of target prediction, intermediate metabolites and potential metabolic pathways. MethodsIn this research, ultraperformance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) technology was used to qualitatively detect the chemical compounds of ROB, and the antithrombotic activity of ROB was evaluated by establishing a zebrafish model. The target function was predicted by network pharmacology, and differential metabolites were screened by metabolomics and multivariate statistical analysis methods. Correlation analysis of network pharmacology and metabolomics screening results was conducted to identify the potential pathway of ROB intervention in thrombosis, and the prediction results were further verified. ResultsROB significantly reduced the reactive oxygen species (ROS) staining intensity in zebrafish induced by phenylhydrazine (PHZ) and improved the inhibition rate of thrombosis. By constructing the “herb-disease-component-target” network, it was concluded that the active ingredients of ROB in treating thrombosis involved emodin, aloe-emodin and physcion, and the key targets included nitric oxide synthase 2 (NOS2) and nitric oxide synthase 3 (NOS3). A total of 341 differential metabolites in zebrafish with thrombosis were screened by partial least squares discriminant analysis (PLS-DA). The results of reverse transcription-polymerase chain reaction (RT–PCR) experiments and targeted metabolomics verification showed that ROB was mainly involved in improving thrombosis by upregulating the expression of NOS3 mRNA and regulating the levels of arginine, glutamate and glutamine in the arginine biosynthesis pathway. ConclusionsROB improved thrombosis by regulating the expression of NOS3 mRNA and the contents of arginine, glutamate and glutamine in the arginine biosynthesis signalling pathway.

Phytochemical, nutritional and antioxidant potential of Panax bipinnatifidus and Panax pseudoginseng: A study of two underutilized and neglected species from the Eastern Himalayan region of India

The world we live in today is rapidly inclining towards plant-based therapeutic and curative medicines. among these phytomedicines, the role of Ginseng's (Panax species) significance as a functional food or nutraceutical has piqued interest in recent years, with a growing market value. Keeping in mind, the present study was intended to analyse the phytochemical, nutritional content and antioxidant activity of two Indian species of Panax viz. P. bipinnatifidus and P. pseudoginseng from the East Himalayan region of India. HPLC studies revealed the presense of four predominant ginsenosides viz. Rg1, Re, Rb1 and Rd in both the Panax species. Analysis of phenolic compounds indicated higher values of gallic acid, chlorogenic acid, and vanillic acid in both species. The tuber contains a good amount of protein, dietary fibre and carbohydrates. Dominant content of arginine and glutamic acid were found with cysteine and methionine as limiting amino acids in both the Panax species. High levels of palmitic, oleic and linoleic acid were observed with higher values of poly-unsaturates in P. pseudoginseng. Analysis of minerals and trace elements reflected high content of phosphorus, potassium, magnesium and selenium in Panax species. The antioxidant study further confirmed the effective potential of these Panax species against several free radicals such as DPPH, ABTS, and superoxide anions. The present findings provide biochemical insights into the diverse aspects of east Himalayan Panax species coupled with their antioxidant potential. These findings could be used as a baseline model for enriching the herbal raw materials required for pharmaceutical as well as nutraceutical formulations. Moreover, a commercially oriented cultivation of these species may be developed by adopting effective conservation strategies to conserve these therapeutically important east Himalayan Panax species.

Arginine Increases Tolerance to Nitrogen Deficiency in Malus hupehensis via Alterations in Photosynthetic Capacity and Amino Acids Metabolism.

Arginine plays an important role in the nitrogen (N) cycle because it has the highest ratio of N to carbon among amino acids. In recent years, there has been increased research interest in improving the N use of plants, reducing the use of N fertilizer, and enhancing the tolerance of plants to N deficiency. Here, the function of arginine in the growth of apple (Malus hupehensis) under N deficiency was explored. The application of 100 μmol L–1 arginine was effective for alleviating N-deficiency stress. Exogenous arginine promoted the absorption and use of N, phosphorus (P), and potassium (K) under low N stress. The net photosynthetic rate, maximal photochemical efficiency of photosystem II, and chlorophyll content were higher in treated plants than in control plants. Exogenous arginine affected the content of many metabolites, and the content of many amino acids with important functions was significantly increased, such as glutamate and ornithine, which play an important role in the urea cycle. Half of the metabolites were annotated to specialized metabolic pathways, including the synthesis of phenolic substances, flavonoids, and other substances with antioxidant activity. Our results indicate that arginine promotes the plant photosynthetic capacity and alters amino acid metabolism and some antioxidants including phenolic substances and flavonoids to improve the tolerance of apple to N deficiency, possibly through the improvement of arginine content, and the absorption of mineral.

Impact of dietary protein levels on growth, feed utilization, body composition, and hematological characteristics of juvenile hybrid pufferfish (Takifugu obscurus × T. rubripes)

In the present study, we aimed to evaluate the optimum dietary protein level in hybrid pufferfish (Takifugu obscurus ♀ × T. rubripes ♂). To this end, we formulated five isoenergetic (16 MJ/kg gross energy) diets with casein with different levels of protein–namely, 35%, 45%, 50%, 55% and 65%. Then, fish with the average weight of 5.68 ± 0.05 g (mean ± SD) were randomly distributed into 15 tanks, 20 animals in each tank. The fish received their diet twice a day (09:00 and 17:00) ad libitum. The results showed that, after the 8-weeks feeding trial, the fish that received 45% and 50% protein diets had significantly higher final weight, WG, and SGR that the fish that received 35% protein diet (p < 0.05). However, final weight, WG and SGR did not differ significantly among the fish that received 35%, 55% and 65% protein diets. Next, the fish on 35% protein diet had a significantly higher PER that their counterparts on 50%, 55% and 65% protein diets (p < 0.05). However, no such difference was observed between the two groups of fish that received 35% and 45% protein diets. Furthermore, the fish on 50% and 55% protein diets had a significantly higher whole body protein content as compared to the fish that received 35% and 65% protein diets (p < 0.05). In addition, the fish on 65% protein diet had a significantly higher whole body lipid content as compared to the group that received 35% protein diet (p < 0.05). In addition, the highest arginine, histidine, phenylalanine, threonine, valine, glutamic acid, proline and tyrosine content were observed in the fish that received 50% protein diet. The fish on 35% and 65% protein diets had a significantly higher hemoglobin than the group on 55% protein diet (p < 0.05); however, no differences were observed among the groups on 45%, 50%, and 55% protein diets. Finally, the fish fed 35% has a significantly higher AST activity that the groups that received 45% and 55% protein diets (p < 0.05); yet, no significant differences were found among the groups on 45%, 50%, and 55% protein diets. The results of two-slope straight broken-line and quadratic broken-line analysis of WG revealed that, for the maximum growth of juvenile hybrid pufferfish, the optimal dietary protein should be 46.3% and 51.5%, respectively.

Comparative Estimation of Arginine Content in Peanuts: An Analytical Study

Introduction: Arginine is an amino acid that has several positive effects on human health and peanut seeds are the richest source of it. Peanuts are the store houses loaded with proteins, fatty acids, vitamins, fiber and other phytochemicals. It has been shown that the intake of arginine at the concentration of 3-6 g/day has been found to improve the cardiovascular system, reduce intestinal permeability and activate the immune system that aids in early recovery of tuberculosis patients. Aim: To evaluate the variation of arginine content in raw, boiled, soaked, soaked and boiled type of peeled and unpeeled peanuts. Materials and Methods: The analytical study on various groups of peanuts (raw, boiled, soaked, soaked and boiled peanuts of both peeled and unpeeled varieties) was conducted at Gayatri Vidya Parishad Institute of Health Care and Medical Technology at Visakhapatnam, Andhra Pradesh, India, in December 2019. The arginine content was estimated in peanut seeds using the Sakaguchi method by Spectrophotometry at wavelength of 520 nm. Descriptive statistics were done for all 12 groups and were represented with mean, standard deviation and standard error. Analysis of Variance (ANOVA), Post-hoc Tukey’s were applied to find statistical significance. The p-value &lt;0.05 was considered as statistically significant. Statistical Package for Social Sciences (SPSS) version 25.0 was used for analysis. Results: Concentration of arginine was recorded for each type in triplicate considering the mean. The raw soaked peeled peanuts had the lowest concentration of arginine (31.82 µg/g) and the soaked boiled for 15 minutes, unpeeled peanuts had the highest amount of arginine (1438.18 µg/g). Significant difference was found among the twelve groups by using ANOVA test p&lt;0.001. Soaked and boiled 15 min peeled peanuts, soaked unpeeled, soaked and boiled 15 min unpeeled and soaked and boiled 30 min unpeeled were significantly different when compared to the remaining groups using Post hoc Tukey’s test p&lt;0.05. Conclusion: Soaked, boiled and unpeeled peanuts were the best types with the highest amounts of arginine which could be chosen as adjuvant nutritional therapeutic supplement to aid in the recovery of certain diseases.

Hodnotenie aminokyselín v mäse a pečeni nutrie (Myocastor coypus Molina) v závislosti od veku

The objective of this research was to evaluate the amino acid composition of proteins in the dorsal muscle, femoral muscle, and the liver of female nutrias (Myocastor coypus Molina) in relation to age. In this study a total of 50 animals were used. The animals were split into two groups based on their age, i.e. 7 months old and 24 months old. The amino acids were separated and quantitatively determined using an automated analyser. Using a two-way analysis of variance, significant differences (P˂0.05) were determined between the tested parameters, muscle type and age. In this study, statistically significant differences were found in the dorsal muscle in the content of glycine, which was higher in young animals and in the content of aspartic acid, which was higher in older animals. In the case of the femoral muscle, significantly higher content of serine, glycine and arginine were found in the group of 7-month-old animals. In contrast, the group of 24-month-old nutria in the femoral muscle showed a higher content of alanine, valine and phenylalanine. In the liver, significantly higher contents of some amino acids were found only in the group of young, 7 months old nutrias. Higher content was observed for aspartic acid, threonine, serine, glutamic acid, proline and histidine. Additionally, nutria meat, particularly meat from the dorsal muscle, is a rich source of amino acids, especially essential amino acid, glutamic acid and aspartic acid, making it yet another quality source of protein in a balanced human diet.

Productivity of chicken broilers at different levels and ratios between arginine and lysine in compound feed

The article presents research to determine the optimal levels and ratios of arginine and lysine in complete feed for broiler chickens of different ages. The object of research was broiler chickens "Cobb-500". The experiments were performed by the group method. During the main period of 42 days, taking into account the age of the chickens, there were three subperiods: 1-10; 11–22; 23–42 days. 600 heads of 1-day-old broiler chickens were selected for the experiments, from which 6 groups of 100 heads each were formed on the principle of analogues. The age and live weight of chickens were taken into account when selecting analogues. Chickens were kept in one room on the floor at a planting density of 12 heads per 1 m2. The feeding front was 2.5 cm, the watering front was 1.5 cm. The air temperature and lighting of the premises corresponded to the sanitary norms adopted in poultry farming. The chickens were fed compound feed twice a day. The level of lysine and arginine in poultry diets was regulated by the introduction of synthetic preparations of these amino acids in the feed. According to the scheme of the experiment, broiler chickens were fed complete feed during the experiment, balanced in metabolic energy and all nutrients, in accordance with the standards recommended by Cobb. The set and quantity of the main ingredients in the feed were regulated depending on the period of growing chickens (1-10, 11-22 and 23-42 days) and the required content of lysine and arginine. As a result of the conducted researches it was established that the wide arginine-lysine ratio helped to increase the growth rate by reducing feed costs per 1 kg of growth in all periods of cultivation. A slight narrowing of the arginine-lysine ratio contributed to gains at the control level, or slightly higher. With a more significant increase in the share of lysine, the gains decreased incredibly, but more significantly, also increased feed costs.

Food-Derived High Arginine Peptides Promote Spermatogenesis Recovery in Busulfan Treated Mice.

Food-derived peptides with high arginine content have important applications in medicine and food industries, but their potential application in the treatment of oligoasthenospermia remains elusive. Here, we report that high-arginine peptides, such as Oyster peptides and Perilla purple peptides were able to promote spermatogenesis recovery in busulfan-treated mice. We found that both Opp and Ppp could increase sperm concentration and motility after busulfan-induced testicular damage in mice. Further research revealed that Opp and Ppp might promote spermatogonia proliferation, which improved blood-testis barrier recovery between Sertoli cells. Taken together, these high-arginine peptides might be used as a medication or therapeutic component of a diet prescription to improve the fertility of some oligoasthenospermia patients.

Effect of dietary replacement of fish meal with low-gossypol cottonseed protein concentrate on growth performance and expressions of genes related to protein metabolism for swimming crab (Portunus trituberculatus)

An eight-week feeding trial was conducted to evaluate the effect of dietary replacement of fish meal with low-gossypol cottonseed protein concentrate (CPC) on growth performance, body composition, amino acid profiles in tissues, antioxidant capacity and the expression levels of genes related to protein metabolism and inflammation for juvenile swimming crab (Portunus trituberculatus). Six isonitrogenous and isolipidic diets (450 g kg−1 protein and 80 g kg−1 lipid) were formulated to contain graded levels of CPC, and fish meal was replaced with CPC at 0, 10%, 20%, 30%, 40% and 60% levels (CPC00, CPC10, CPC20, CPC30, CPC40 and CPC60), free gossypol concentrations in experimental diets were analyzed to be 0, 32.62, 66.10, 106.71, 133.13, 192.21 mg kg−1 respectively. Arginine, lysine and methionine were added to ensure consistency of these three essential amino acids in all experimental diets. Each diet was randomly assigned to triplicate groups of 30 juvenile swimming crabs (approximately initial weight 7.59 ± 0.06 g) that were stocked in rectangle plastic baskets. Results of present study indicated that crabs fed the CPC60 diet had the lower final weight (FW), percent weight gain (PWG), specific growth rate (SGR) and feed efficiency (FE) than those fed the CPC20 diet, and crabs fed the CPC20 and CPC30 diets had the highest survival among all treatments, and the lowest survival was occurred at crabs fed the CPC60 diet. The hepatopancreas color was blackened with the replacement levels of fish meal with CPC increasing from 0% to 60%. Free gossypol concentration in hepatopancreas significantly increased with increase of dietary replacement levels of fish meal with CPC. Crabs fed the CPC40 and CPC60 diets had lower lipid content in whole body than those fed the other diets. Arginine, lysine, methionine and isoleucine contents in muscle were significantly influenced by dietary replacement levels of fish meal with CPC. ALT, AST, TP, ALB, HDL and ALP in hemolymph, and T-AOC, ALT, AST, SOD, GSH, GSH-ST in hepatopancreas were significantly affected by dietary replacement of fish meal with CPC. Dietary replacement levels of fish meal with CPC could influence the expressions of genes related into protein metabolism such as tor, akt, s6, s6k1, 4ebp1, eif4e1a, eif4e2, eif4e3, antioxidant and immune such as gpx, cat, cMnsod and lysozyme, as well as growth such as tlr4, irak4, myd88, traf6, and inflammation such as relish. In conclusion, based on two slope broken-line and quadratic broken-line regression analysis of PWG against the dietary replacement of fish meal with CPC, the optimal replacement level of fish meal with CPC was estimated to be 19.07% and 22.73% for juvenile swimming crab, respectively. Results demonstrated that CPC could partially replace fish meal, but had no negative effects on growth performance, antioxidant activity and immunity of swimming crab.

The Role of the pH in the Impregnation of Spherical Mesoporous Silica Particles with L-Arginine Aqueous Solutions.

In the context of the development of carriers for amino acids delivery, Spherical Mesoporous Silica Particles (SMSP), characterized by particles size ranging from 0.15 µm to 0.80 µm and average pore diameter of 2.4 nm, were synthesised and loaded with L-arginine (ARG), a basic amino acid involved in several physiological processes. The loading was performed using water as a solvent through the wet impregnation method (with a final arginine content of 9.1% w/w). The material was characterized before and after impregnation by means of X-Ray Diffraction (XRD), nitrogen sorption analysis, Field Emission Scanning Electron Microscopy (FESEM) and Fourier Transform Infrared (FT-IR) spectroscopy. SMSP are shown to suffer degradation upon impregnation, which dramatically affects their porosity. To elucidate the role of the pH of the ARG impregnating solution (originally set at pH ≈ 11) on SMSP degradation, the loading was performed under different pH conditions (5 and 9) keeping constant the ARG concentration. The impregnation performed with acidic solution did not modify the carrier. All samples displayed ARG in amorphous form: zwitterionic species were present in SMSP impregnated at basic pH whereas positive protonated species in that impregnated at acidic pH.

Effects of almonds on ameliorating salt-induced hypertension in dahl salt-sensitive rats.

Excessive dietary salt intake is related to an increased risk of hypertension. Dietary functional foods probably could help to improve salt-induced hypertension. In this study, Dahl salt-sensitive (DSS) rats were used to investigate their metabolic differences from those of salt-resistant SS.13BN rats and determine whether dietary protein-rich almonds could ameliorate salt-induced elevation of blood pressure in DSS rats. After high-salt intake, the systolic blood pressure and mean arterial pressure of the DSS rats increased dramatically. Metabolomics analysis indicated abnormal amino acid metabolism in their kidneys. Their renal nitric oxide (NO) content and nitric oxide synthase activity decreased significantly after high-salt diet. Oxidative stress also occurred in DSS rats. After the DSS rats received almond supplementation, the levels of various amino acids in their kidney increased, and renal arginine and NO contents were upregulated. Their renal hydrogen peroxide and malonaldehyde levels decreased, whereas renal catalase, superoxide dismutase and glutathione peroxidase activities and glutathione levels increased. The renal abnormal amino acid metabolism of DSS rats contributed to the impaired NO production in response to high-salt intake. Together with salt-induced oxidative stress, high-salt diet intake ultimately led to an increase in the blood pressure of DSS rats. Protein-rich almond supplementation might prevent the development of salt-induced hypertension by restoring arginine and NO regeneration and alleviating salt-induced oxidative stress. © 2021 Society of Chemical Industry.

Effects of dietary arginine on growth, activity of digestive enzymes, GCN2‐ATF4 signalling pathway and nutritional metabolism‐related gene expression of large yellow croaker ( Larimichthys crocea ) larvae

A 30-day feeding experiment was conducted to elucidate the effects of dietary arginine on growth performance, activity of digestive enzymes, GCN2-ATF4 signalling pathway and nutritional metabolism-related gene expression of large yellow croaker larvae (initial weight: 10.56 ± 0.26 mg). Four isonitrogenous and isolipidic diets with different arginine levels (19.5, 31.0, 39.6 and 48.6 g kg−1 of dry matter) were formulated. Results showed that no significant differences in survival, growth and whole-body proximate composition were observed among dietary treatments. The whole-body arginine content of fish larvae was significantly increased with increasing contents of dietary arginine, and the maximum was observed in larvae fed the diet with 48.6 g kg−1 arginine. However, the contents of other amino acids were not significantly affected. Larvae fed the diet with 19.5 g kg−1 arginine showed higher activity of alkaline phosphatase (AKP) in the intestinal segments (IS) and brush border membranes (BBM) than other groups. The expression of GCN2-ATF4 signalling pathway-related genes (atf4, chop and asns) in the visceral mass of larvae was significantly upregulated by dietary 39.6–48.6 g kg−1 arginine supplementation. Dietary 48.6 g kg−1 arginine significantly upregulated the expression of proteolytic genes (murf1 and glud) in the visceral mass of larvae. Furthermore, the highest expression of genes related to fatty acid β-oxidation (cpt1α) and glycolysis (gk and pk) was observed in the 39.6 g kg−1-arginine group. In summary, those results suggested that dietary arginine had no significant influence on the growth performance of large yellow croaker larvae. However, the arginine level significantly affected the arginine content of whole larvae, activity of digestive enzymes, lipid metabolism and glycolysis of larvae. The GCN2-ATF4 signalling pathway was stimulated by high-dose (31.0–48.6 g kg−1) arginine, maybe due to the antagonistic effect of arginine and lysine. These results might indicate that 19.5 g kg−1 dietary arginine (37.6 g kg−1 dietary protein) could meet the growth requirement of large yellow croaker larvae.