Glycine Content Research Articles

Effect of Drying on Nutritional Composition of Atlantic Sea Cucumber (Cucumaria frondosa) Viscera Derived from Newfoundland Fisheries

Cucumaria frondosa is the main sea cucumber species harvested from Newfoundland waters. During processing, the viscera of sea cucumber are usually discarded as waste. As a matter of fact, sea cucumber viscera are abundant in various nutrients and promising for valorization. In the present study, sea cucumber viscera were pretreated by air drying and freeze drying, and the nutritional compositions of the dried products were investigated, including proximate composition, lipid class, fatty acid profile, and amino acid composition. The dried viscera had similar levels of ash, lipids, and proteins compared to fresh viscera. Both air- and freeze-dried viscera had total fatty acid composition similar to fresh viscera, with high levels of omega-3 polyunsaturated fatty acids (PUFAs) (30–31%), especially eicosapentaenoic acid (27–28%), and low levels of omega-6 PUFAs (~1%). The dried samples were abundant in essential amino acids (46–51%). Compared to air-dried viscera, freeze-dried viscera contained a lower content of moisture and free fatty acids, and higher content of glycine and omega-3 PUFAs in phospholipid fraction. The high content of nutritious components in dried viscera of Cucumaria frondosa indicates their great potential for valorization into high-value products.

COMPREHENSIVE EVALUATION OF SOYBEAN AND SUNFLOWER PROCESSING PRODUCTS

The literature review of the article presents the characteristics of the protein value of plant feed materials, in particular, of soybean and sunflower processing products, depending on the production technology. Their amino acid composition ideally meets the needs of young animals and poultry due to the high content of essential amino acids.
 The section «Materials and methods» presents methods for determining: crude protein by the Kjeldahl method, soluble protein in 0.2% potassium hydroxide, Barnstein protein, falsification of protein products with inorganic nitrogen, as well as characteristics of methods for determining the content of essential and non-essential amino acids, incl. sulfur-containing, using the system of capillary electrophoresis «Drops-105M».
 As a result of the research it was found that of the total number of analyzed samples of soybean meal in terms of protein content, 30.8% of products did not meet the declared values of producers and were in the range of 37.4 - 40.8%, in terms of protein solubility were in the range of 75 - 78%, which meets the norms of feeding.In addition, 5.0% of the total number of samples analyzed, were falsified after Bard alcohol, falsification of inorganic nitrogen was not found. The use of low-protein raw materials for the production of sunflower meal and cake was reflected in their protein content and ranged from 26.3 to 33.7%.
 Fermented soybean product and toasted soybean meal are characterized by a higher total content of essential amino acids in the protein, which was 26.3% and 27.2%, respectively, compared with full-fat expanded soybean expanded, where this figure was at 20.25%, and prevailed other analyzed products by methionine, threonine, tyrosine, phenylalanine, proline, alanine etc.
 The analyzed sample of sunflower meal, produced by a special technology is equivalent in total amino acid content in the studied soy products. Its content of methionine was 1.5 and 2.1 times higher, compared with toasted soybean meal and full-fat soybean, respectively. Also, the content of threonine, glycine, cystine, tryptophan, aspartic and glutamic acids in the sample of sunflower meal prevailed the content of the same amino acids in soybean products.
 Thus, the comprehensive assessment of plant protein components makes it possible to control not only the quantitative content of protein and amino acids, but also provides a detailed assessment of feeding.

A comparison of the photosynthesis response to arsenic stress in two Pteris cretica ferns

The present study investigated the effect of arsenic (As) on photosynthesis and other selected physiological parameters in two ferns. The ferns (Pteris cretica 'Albo-lineata' and 'Parkerii') subjected to As doses of 100 and 250 mg kg-1 for three months, showed different As accumulation, which was higher in Albo-lineata. Overall, the obtained results indicated significant differences between studied ferns. The individual effects of As and growing period on all parameters were very variable. However, As doses generally caused a decrease of net photosynthetic rate, stomatal conductance, transpiration rate, maximum quantum yield of PSII, and photosynthetic pigments. The sampling period effect was significant for magnesium content of Parkerii (decrease) and contents of photosynthetic pigments of Albo-lineata (increase) and Parkerii (decrease). Results showed that Parkerii had higher sensitivity to As doses than Albo-lineata, which was also reflected by the higher free glycine content and its increase by As doses.

Pharmacological Evidence on Augmented Antiallodynia Following Systemic Co-Treatment with GlyT-1 and GlyT-2 Inhibitors in Rat Neuropathic Pain Model.

The limited effect of current medications on neuropathic pain (NP) has initiated large efforts to develop effective treatments. Animal studies showed that glycine transporter (GlyT) inhibitors are promising analgesics in NP, though concerns regarding adverse effects were raised. We aimed to study NFPS and Org-25543, GlyT-1 and GlyT-2 inhibitors, respectively and their combination in rat mononeuropathic pain evoked by partial sciatic nerve ligation. Cerebrospinal fluid (CSF) glycine content was also determined by capillary electrophoresis. Subcutaneous (s.c.) 4 mg/kg NFPS or Org-25543 showed analgesia following acute administration (30–60 min). Small doses of each compound failed to produce antiallodynia up to 180 min after the acute administration. However, NFPS (1 mg/kg) produced antiallodynia after four days of treatment. Co-treatment with subanalgesic doses of NFPS (1 mg/kg) and Org-25543 (2 mg/kg) produced analgesia at 60 min and thereafter meanwhile increased significantly the CSF glycine content. This combination alleviated NP without affecting motor function. Test compounds failed to activate G-proteins in spinal cord. To the best of our knowledge for the first time we demonstrated augmented analgesia by combining GlyT-1 and 2 inhibitors. Increased CSF glycine content supports involvement of glycinergic system. Combining selective GlyT inhibitors or developing non-selective GlyT inhibitors might have therapeutic value in NP.

Production of Porous Stainless Steel using the Space Holder Method

Metallic foams and porous materials can be produced by various methods. Among the methods that can produce metallic foams and porous materials, powder metallurgy is a promising method. This study investigates the production of a porous stainless steel by the space holder method in powder metallurgy. A novel space holder i.e. glycine and binder consisting of polymethylmethacrylate and stearic acid are used. Different amounts of glycine are added to the mixture of stainless-steel powder and binder. Subsequently, each mixture is cold-pressed at a pressure of 9-ton m-2. The samples are sintered at 1050 and 1150 °C with holding times of 30, 60, and 90 min. The microstructures and physical and mechanical properties of the sintered samples are investigated. A porous stainless steel with porosity ranging from 30.8 to 51.4% is successfully fabricated. Results show that the glycine content and sintering parameters influence the properties of the porous stainless steel. The sintering temperature significantly affects volumetric shrinkage. Volumetric shrinkage decreases as the volume fraction of glycine increases to 30% whereas sintering temperature 1150 °C and holding time 90 min will increase the volumetric shrinkage. The compressive yield strength and corresponding elastic modulus are in the ranges of 22.9 to 57.6 MPa and 6.3 to 26.8 GPa, respectively. The samples produced have potential biomedical applications because their mechanical properties, yield strength and elastic modulus match those of human bones.

Sr2Ni0.7Mg0.3MoO6-δ: Correlation between synthesis conditions and functional properties as anode material for intermediate-temperature SOFCs

The Sr2Ni0.7Mg0.3MoO6-δ double perovskites synthesis has been performed by a pyrolysis of organic-nitrate compositions with various ratios of ϕ (glycerol- or glycine content) and R (ammonium nitrate content). The solution combustion study revealed that the redox mixture composition for the Sr2Ni0.7Mg0.3MoO6-δ synthesis influenced the pyrolysis temperature, thermochemical charge generation, particles size, phase composition and physicochemical properties of the final oxide material. Investigations of thermodynamic stability, thermal expansion and electrical conductivity demonstrated that the Sr2Ni0.7Mg0.3MoO6-δ sample, obtained via pyrolysis synthesis with glycine triple excess without exothermic additive, may be considered as a prospective anode material for intermediate-temperature solid oxide fuel cells. It was confirmed by the sample stability in oxidative and reducing atmospheres, optimal values of linear coefficient of thermal expansion (14.4·10−6 K−1 in air; 13.1·10−6 K−1 in 50% H2/Ar) and the highest electrical conductivity value (0.53 S cm−1 at 800 °C in air) among glycine-samples.

High performance liquid chromatography determination of L-glutamate, L-glutamine and glycine content in brain, cerebrospinal fluid and blood serum of patients affected by Alzheimer's disease.

Altered glutamatergic neurotransmission is thought to play a crucial role in the progression of Alzheimer's disease (AD). Accordingly, the identification of peculiar biochemical patterns reflecting AD-related synaptopathy in blood and cerebrospinal fluid (CSF) could have relevant diagnostic and prognostic implications. In this study, we measured by High-Performance Liquid Chromatography the amount of glutamate, glutamine and glycine in post-mortem brain samples of AD patients, as well as in CSF and blood serum of drug-free subjects encompassing the whole AD clinical spectrum (pre-clinical AD, n = 18, mild cognitive impairment-AD, n = 29, dementia AD, n = 30). Interestingly, we found that glutamate and glycine levels, as well as total tau protein content, were significantly reduced in the superior frontal gyrus of patients with AD, compared with non-demented controls. No significant change was also found in glutamate, glutamine and glycine CSF concentrations between AD patients and neurological controls. Remarkably, serum glutamate levels were significantly higher in patients affected by early AD phases compared to controls, and were negatively correlated with CSF total tau levels. Conversely, serum glutamine concentration was significantly increased in AD patients, with a negative correlation with MMSE performances. Finally, we reported a significant correlation between serumL-glutamate concentrations and CDR score in female but not in male cohort of AD subjects. Overall, our results suggest that serum glutamate and glutamine levels in AD patients could vary across disease stages, potentially reflecting the progressive alteration of glutamatergic signaling during neurodegenerative processes.

Nutritive evaluation, metabolisable energy and digestible amino acid contents of different indigenous feedstuff for Nile tilapia (Oreochromis niloticus).

Three trials were executed to examine the nutritive profile, metabolisable energy and digestible amino acid (AA) contents of four indigenous feed ingredients including wheat (W), wheat middling (WM), canola meal (CM) and rapeseed meal (RSM) in Nile tilapia. Three samples of each test ingredient were collected from three different locations of Multan (MUL) and Sukkar (SKR), of Pakistan. The collected three samples were pooled thereafter to make a homogenous/ representative sample of each test ingredient from a particular study site. Nutrients composition, AA and energy digestibility of these indigenous ingredients were evaluated by using laboratory analyses and fish studies. Proximate analysis indicated variations in some of the nutrients due to location (p < 0.05). Differences were also observed in some AA including arginine, lysine, serine, cysteine, glutamic and aspartic acids, histidine, valine and glycine contents of these ingredients (p < 0.05). Digestibility of leucine, glycine and glutamic acid was higher (p < 0.05) in RSM from MUL. Among W samples from MUL, AA digestibility for lysine, threonine, and aspartic acid was higher (p < 0.05). Crude protein, arginine, alanine, serine, and aspartic acid had higher digestibility (p < 0.05), whereas digestibility was lower (p < 0.05) for threonine, valine and tyrosine in RSM from MUL. Metaboliseable energy contents did not differ among W, WM, CM and RSM regarding their origin (p > 0.05). The results indicated that nutritional profiles and their digestibility indices vary with the location for Nile tilapia.

Effect of the Addition of Milk Protein Preparations on Selected Quality Parameters and Nutritional Characteristics of Kefir

The aim of this study was to evaluate the effect of the addition of various milk protein powder preparations (MPC-80, WPC-70, sweet whey, non-demineralized or demineralized whey, whey permeate, rennet casein, buttermilk) to selected quality parameters and digestibility of milk proteins in kefir. Kefir samples analyzed in the study were prepared under laboratory conditions with three industrial bacterial starter cultures. They were examined microbiologically (lactobacilli, lactococci, yeast) and for pH, total protein content, hardness, adhesiveness, water-holding capacity (WHC), and protein digestibility (using two in vitro methods along with the determination of the content of available lysine and glycine). The counts of lactococci and lactobacilli were estimated at levels above 7 and 6 log(CFU/mL), respectively. Yeast was not found in the kefir samples. The pH value of the samples was 4.4–5.2. The pH, hardness, adhesiveness, and WHC were dependent on the type of kefir starter culture and the type of milk protein powder added. Each protein preparation added increased the amount of available lysine and glycine. However, when converted for 1 g of kefir protein, the changes in the content of available lysine and glycine were variable and depended on both the milk protein powder and starter culture used.

Preparation of a functional beverage with α-glucosidase inhibitory peptides obtained from ginkgo seeds.

To obtain α-glucosidase inhibitory peptides from ginkgo seeds and use it to develop beverages, papain hydrolysis was used to hydrolyze and extract ginkgo seed peptides. Through ultrafiltration and semi-preparative high performance liquid chromatography, peptide fragments which were molecular weight of < 10KDa with high α-glucosidase inhibition rate were separated and purified to prepare beverages. At the same time, the A1, A2, B1, and B2 peptide fragments purified by semi-preparative high performance liquid chromatography were analyzed for amino acid composition. All four peptide fragments have glutamate. Studies have shown that amino acids such as glutamate can promote postprandial insulin secretion and reduce glucose levels. The result indicates that the amino acid composition may be related to the inhibition rate of α-glucosidase. After orthogonal experiment design, analysis of variance and principal component analysis, when 5% xylitol and 0.3% citric acid were added, and the glycine content was 1.2%, the ginkgo polypeptides beverage had the best flavor.

Collagen isolation and characterization from Sardinella longiceps.

Objective:Collagen is a fibrous protein that is primarily used in the pharmaceutical and biomedical industries. This study isolates and characterizes type-1 collagen from Sardine longiceps (scales, skin, and muscle).Materials and Methods:Collagen was isolated from S. longiceps using two methods: acid-solubilized collagen and pepsin-solubilized collagen. Sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS–PAGE) was used to estimate the molecular weight of isolated collagen. Ultraviolet (UV)-visible spectrophotometry analysis was used to confirm the collagen extracted (type-I collagen). The functional groups of isolated collagens were identified using fourier transform infrared (FTIR) analysis. The X-ray diffraction (XRD) technique was used to investigate the crystallinity of isolated collagen. The high-pressure liquid chromatography (HPLC) technique was used to study the amino acid composition.Results:SDS–PAGE of S. longiceps revealed molecular weights ranging from 116 kDa for α-2 to 97 kDa for α-1. UV-visible spectra showed an absorbance value below 300 nm, and the results confirmed type-I collagen. FTIR showed major functional groups like amide A, B, I, II, and III. XRD determined the crystallinity of isolated collagen. The HPLC results showed the presence of higher glycine content, followed by proline and hydroxyl proline in the extracted collagen.Conclusion:The overall study confirmed that fish waste materials (scales, skin, and muscles) could be used as an alternative source for collagen.

Revisiting amino acid analyses for bioadhesives including a direct comparison of tick attachment cement (Dermacentor marginatus) and barnacle cement (Lepas anatifera)

With respect to potential applications in healthcare, pharmacy, the bonding industry, and cosmetics, biological adhesives produced from various animals are of high interest. A large number of species in the family Ixodidae produce an adhesive substance called attachment cement. This study focuses on the detailed investigation of the amino acid composition of the attachment cement from ticks (Dermacentor marginatus) and comparison with cement samples from barnacles (Lepas anatifera).Strong emphasis was laid on sample preparation of both types of cement and included the complete hydrolysis of proteins under either basic or acidic conditions. Stability of propyl chloroformate derivatives of the amino acids were measured by liquid chromatography electrospray ionisation tandem mass spectrometry (LC-ESI-MS/MS) and gas chromatography electron ionisation tandem mass spectrometry (GC-EI-MS/MS) and were validated in terms of reproducibility and precision of analyses using NIST certified amino acid as well as protein standards. For the majority of the amino acids analytically valid recovery rates between 86 and 111% were achieved using GC-EI-MS/MS analysis after acidic hydrolysis.The method was applied for direct comparison of two biological glue systems, tick and barnacle cement. An outstandingly high content of glycine was present in the tick attachment cement; as were significant concentrations of leucine, serine and proline. In contrast, high levels of leucine, serine, aspartic acid/asparagine, glycine, glutamic acid/glutamine, alanine and valine were determined for barnacle cement. None of the samples showed the presence of 3,4-dihydroxy-phenylalanine (DOPA), yet tick attachment cement exhibited significantly higher concentration levels of tyrosine, the precursor of DOPA. It can clearly be stated that published results for amino acid analysis of barnacle cement show significantly under-/overestimation for some amino acids.Distinct differences in amino acid presence and concentration were observed for the two bio-adhesives. Although both have cement-like properties the data implied that different attachment mechanisms are involved for each of the organisms.

Effects of processing step, filling medium and storage on amino acid profiles and protein quality in canned European eels

This study evaluated the effects of the canning process and different filling media (sunflower oil, olive oil and spiced olive oil) on the amino acid profiles and protein quality of eels. Thawing-salting did not alter the amino acid contents. However, frying increased the content of some amino acids. The changes observed during the sterilization process depended on the filling medium. Inclusion of spices in the packing medium favoured loss of the amino acid lysine. The amino acids underwent greater changes during storage, although the changes varied depending on the amino acid considered. A large decrease in the glycine content was observed after storage of canned eels for 12 months. The changes were also influenced by the filling medium and were particularly evident in the eels packed in spiced olive oil. Essential amino acid scores (EAAs) and essential amino acid indices (IEAA) increased during the 12-month storage period. The amino acid contents indicated that the best quality product was the canned eels packed in sunflower oil.

Evaluation of the efficacy of potential anesthetic agents on cuttlefish (Sepia pharaonis) juveniles

Anesthesia is often used to relieve stress and reduce mortality rates in aquaculture systems. Here, we assessed the efficacy of four anesthetic agents on cuttlefish (Sepia pharaonis) juveniles. Concentration-response trials were performed to evaluate the induction time and recovery period after short-term anesthesia. MS-222 (5−100 mg L−1) was unable to induce anesthesia in cuttlefish juveniles. Treatment of the cuttlefish with 0.2−3 ml L−1clove oil induced death. By contrast, the anesthetization of cuttlefish with magnesium chloride solution (0.0125−0.2 mol L−1) and ethanol (2.5−30 mL L−1) was successful and the cuttlefish recovered well. Analysis of water quality index during simulated transportation revealed that 0.0125 mol L−1magnesium chloride solution was effective for cuttlefish transport for at least 12 h. 1H NMR spectroscopy coupled with multivariate data analysis and univariate data analysis were performed to reveal the metabolites in the cuttlefish central nervous system influenced by MgCl2. A total of 23 metabolites including amino acids, carboxylic acids, choline, betaine, nucleosides and nucleotides were identified. Levels of isoleucine, leucine, valine, tyrosine and glutamate were altered following anesthetization. Magnesium chloride indirectly increased the content of the inhibitory neurotransmitter glycine. It also reduced the content of excitatory neurotransmitter Dopamine by increasing the content of tyrosine thereby achieving anesthetization.

Translocon-Associated Protein Complex (TRAP) is Crucial for Co-Translational Translocation of Pre-Proinsulin

Many unanswered questions remain in understanding the biosynthesis of the peptide hormone insulin. Here we elucidate new aspects in the mechanism of co-translational translocation initiation of pre-proinsulin in the endoplasmic reticulum. We utilize a translational arrest peptide derived from the x-box-binding protein (Xbp1) to induce ribosomal stalling and generate translocation intermediates. We find that the insulin signal sequence is rather weakly gating and requires the assistance of auxiliary translocon components to initiate translocation. Probing the translational intermediates with chemical crosslinking, we identified an early interaction with the translocon-associated protein (TRAP) complex. The TRAPβ subunit interacts with pre-proinsulin before the peptide enters the Sec61 translocon channel in a signal sequence-dependent manner. We describe the substrate sequence determinants that are recognized by TRAP on the cytosolic site of the membrane to facilitate substrate-specific opening of the Sec61 translocon channel. Our findings support the hypothesis that the TRAP-dependence is in part determined by the content of glycine and proline residues mainly within the signal sequence.

Comparative Studies on the Chemical Composition of Inland Saline Reared Litopenaeus vannamei

ABSTRACT A comparative study of chemical composition between the muscles of Litopenaeus vannamei reared in inland saline water (ISRV) and brackish water (BWRV) was taken up. Slightly higher water content, pH, nonprotein nitrogen fractions were observed in ISRV. Some amino acids like glutamic acid, aspartic acid, arginine, lysine and glycine contents were higher in BWRV. On the contrary, ISRV meat had higher hydroxyproline, alanine and leucine content. The polyunsaturated fatty acid content of BWRV and ISRV samples were 41.67% and 46.50%, respectively. Potassium was the dominant mineral in both BWRV and ISRV shrimp meats, i.e., 1011 and 836.3 mg/100 g of meat, respectively. The proportion of composition varied with both the shrimp sample. Though the composition was varied most of the amino acids, fatty acids and minerals were comparable to one another. Therefore, it can be concluded that the overall meat quality of ISRV shrimp is not affected.

Research of water extraction from xenoderm as an active pharmaceutical ingredient in drugs

Today, burns are one of the most common types of injuries in the home and at work around the world. Therefore, the issue of treatment of burns remains relevant today for medicine and pharmacy in particular.&#x0D; In Ukraine, the method of treatment of burns using xenodermoimplants from porcine skin is used, and therefore the crushed substrate of cryolyophilized porcine skin (xenoderm) is a promising active ingredient in the technology of various drug forms.&#x0D; The aim of the work was to study the structural and mechanical properties of water extract from the crushed substrate of the xenoderm and to determine its amino acid composition by using physicochemical analysis, namely using high performance liquid chromatography (HPLC).&#x0D; A glass pycnometer and a Heppler BH 2 MLW drop ball viscometer were used to determine the density and viscosity of the water extract from the xenoderm. The density and viscosity of the water extract were studied at different temperatures.&#x0D; The dependence of the density and viscosity of the water extract from the xenoderm on temperature was studied and it was found that with increasing temperature the dynamic viscosity decreases and the density changes slightly.&#x0D; A glass pycnometer and a viscometer with falling ball were used to determine the density and viscosity of the xenoderm water extract. Chromatographic separation of amino acids was performed on a liquid chromatograph Agilent 1200 with a fluorescent detector.&#x0D; Chromatographic determination of amino acids was performed on a liquid chromatograph Agilent 1200 (USA) with a fluorescent detector G1315A (USA) and an autosampler 1313A.&#x0D; Using the HPLC method, 16 amino acids were identified (essential – 6; conditionally – 2; nonessential – 8). Identified amino acids are almost in a bound state (1.5%), the largest amount is glutamic acid (0.23%), glycine (0.19%), aspartic acid (0.18%), proline (0.17%) and arginine (0.17%). In unbound form, the content of glutamic acid (0.09%) and glycine (0.06%) is the highest.&#x0D; Based on the results of research, you can choose quality indicators, to determine the appropriate criteria that can be proposed for the standardization of water extract from the crushed substrate of the xenoderm.

Comparative analysis of the morphology, karyotypes and biochemical composition of muscle in Siniperca chuatsi, Siniperca scherzeri and the F1 hybrid (S. chuatsi ♀ × S. scherzeri ♂)

Combining morphological comparison with karyotyping can make a more accurate and comprehensive study of mandarin fish (Siniperca spp.) and hybrid progenies.In recent years, the domestication of hybrid mandarin fish has become a hot spot in China, and it is essential to evaluate the nutritional value of the fish after food conversion. In this study, the F1 hybrid (S. chuatsi ♀ × S. scherzeri♂) were fed with artificial feed for five months. Afterwards, we studied the morphology, karyotypes, and biochemical composition of muscle in the F1 hybrid and its parents. The morphological results showed that total length and body height of the F1 hybrid appear to derive more from S. chuatsi than S. scherzeri. The DNA ploidy and karyotype results indicated that the F1 hybrid have a diploid chromosome number (2n = 48) and the same karyotypes (2n = 4sm + 14th+30t, NF = 52) with its parents, suggesting that the chromosome of the mandarin fish has convergence in the process of evolution. The results of biochemical composition of muscle showed that there were no significant difference in other nutritional indicators (P > 0.05), except the Gly (glycine) content of the F1 hybrid was significantly higher than that of S. chuatsi (P < 0.05) under the experimental feeding regime, suggesting that the nutritional value of the F1 hybrid with artificial feeding culture is also higher. The study is expected to provide a reference for further research on the domestication, classification, chromosomes, and nutritional requirements of mandarin fish.

Enhancement of the wear resistance of Ni-diamond composite coatings via glycine modification

Experimental research on the modification of glycine to enhance the wear resistance of nickel-based diamond composite coatings was conducted in this paper. Ni-diamond composite coatings, fabricated from a plating bath, were modified by adding glycine with different contents through co-electrodeposition technology. The surface morphology, diamond content, surface roughness, nickel grain size and microhardness of the composite coatings were investigated by using scanning electron microscopy, energy dispersive spectroscopy, three-dimensional profiler, X-ray diffraction analysis and microhardness tester measurements, respectively. The tribological properties of the composite coatings were evaluated using a reciprocating ball-on-disk tester. The results revealed that the Ni-diamond composite coating with improved diamond content and optimal nickel grain size was modified by a glycine content of 10 g l−1, further increasing its microhardness by 66% to 580 HV. Simultaneously, the surface roughness was also decreased by glycine modification. Owing to the increased diamond content and the reduced surface roughness, the friction coefficient of the composite coating was effectively reduced by 33%. With increasing microhardness and decreasing friction coefficient, the wear rate of the composite coating was reduced by 53%, and the cutting volume was increased by 60%, thus significantly enhancing the wear resistance of the coatings.

UHPLC-QTOFMS-based metabolomic analysis of serum and urine in rats treated with musalais containing varying ethyl carbamate content.

The aim of this work is to investigate the effect of the ethyl carbamate (EC) content in musalais on the metabolism of rats. Electron beam irradiation was performed to decrease the content of EC in musalais, and Sprague Dawley rats were subjected to intragastric administration of musalais with varying EC content (high, medium, and low groups). Control rats were fed normally without any treatment. Serum and urine samples were analyzed using ultra-high-performance liquid chromatography quadrupole time-of-flight mass spectrometry. Principal component analysis and orthogonal projections to latent structures discriminant analysis (OPLS-DA) were performed to detect changes in the metabolite profile in the serum and urine in order to identify the differential metabolites and metabolic pathways. The results demonstrated clear differences in the serum and urine metabolic patterns between control and treatment groups. Ions in treatment groups with variable importance in the projection of >1 (selected from the OPLS-DA loading plots) and Ps < 0.05 (Student t test) compared to control group were identified as candidate metabolites. Analysis of the metabolic pathways relevant to the identified differential metabolites revealed that high EC content in musalais (10mg/kg) mainly affected rats through valine, leucine, and isoleucine biosynthesis and nicotinate and nicotinamide metabolism, which were associated with energy metabolism. In addition, this work suggests that EC can induce oxidative stress via inhibition of glycine content.