Free Essential Amino Acids Research Articles

Morphological and biochemical effects of food deprivation during the early development of Pacific red snapper Lutjanus peru.

We report the effects of food deprivation on the early development of Pacific red snapper Lutjanus peru during the first days of development. The point of no return (PNR) was determined using the feeding incidence after a delay in first feeding. The gradual deterioration of the larvae during food deprivation was recorded using morphometric, histological, enzymatic and biochemical analysis. The time to reach the PNR was 120 h after hatching. Morphologically, the total length, muscle height, head length, tail length and pectoral angle showed the biggest reductions and their growth coefficients changed significantly during food deprivation. Histologically, enterocyte height also was reduced significantly. The protein concentration and activities of the digestive enzymes trypsin, cathepsin-like and lipase showed a significant decrease; meanwhile, amylase activity remained constant during food deprivation. The concentration of total essential free amino acids (EFAAs) decreased significantly while that of the nonessential free amino acids (NEFAAs) remain stable during food deprivation. The most abundant EFAAs were lysine, leucine, isoleucine and valine; the most abundant NEFAAs were alanine, glycine and glutamate, suggesting a more prominent role as energy substrates. At the time of the PNR the concentration of almost all the free amino acids showed a significant decrease. Early food deprivation has a significant impact on the morphology and biochemical characteristics of L. peru. These results suggest that initial feeding of L. peru should begin within 3 days of yolk sac depletion to avoid the PNR. Further studies are necessary to confirm and validate the characters identified in this study as biomarkers of starvation under culture conditions and evaluate their possible utility in ichthyoplankton surveys.

Amino acid availability of processed Brassica carinata meals in hybrid striped bass Morone chrysops ♀ x M. saxatilis ♂

An earlier study showed that hybrid striped bass (Morone chrysops ♀ x M. saxatilis ♂) diets containing 20 % animal meals and up to 30 % aerobically fermented (AF) carinata meal (Brassica carinata, CM) followed by a single wash with water (AFCM) or 30 % CM double-washed with water without AF (WCM), resulted in similar growth. However feed utilization and Fulton’s condition factor of 30 % WCM were better. The current study investigated effects of AFCM and WCM on amino acid digestibilities using naive fish. Effects of AFCM and WCM on trypsin activity, and amino acid availability were determined using hybrid striped bass fed experimental diets for 127 and 148 days, respectively (after a growth trial). High (30 %) AFCM reduced all essential amino acids (EAA) and conditionally EAA (CEAA) except histidine, methionine and threonine. However, all EAA and CEAAs except lysine and cysteine were digested better in 30 %WCM than 30 % AFCM. High (30 %) CMs resulted in generally high serum free methionine and tryptophan, but less leucine for the first 9 h. However, 30 % WCM resulted in generally more serum free arginine and valine than 30 % AFCM. High CMs increased muscle free histidine. Generally, WCM resulted in more muscle lysine and valine than AFCM. Muscle methionine was increased by CMs. Both serum and muscle free total EAAs in hybrid striped bass fed 30 % WCM were elevated continuously over a longer period above the baseline levels. Using EAA:lysine, only muscle histidine were adequate for muscle synthesis over the 36-h period. Overall, amino acids were more available in WCM than AFCM.

Bioactive Compounds Produced by the Accompanying Microflora in Bulgarian Yoghurt

Bulgarian yoghurt is associated with health benefits and longevity of consumers. The specific microflora producing bioactive metabolites is responsible for this effect. The present study examines the biodiversity in four homemade yoghurts from regions containing endemic microflora. Metagenome sequencing indicated Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus were predominant in all samples. In addition, yoghurts contained accompanying lactic acid bacteria (LAB) including Lacticaseibacillus paracasei, Lb. helveticus, Limosilactobacillus fermentum, Lb. rhamnosus, Lactococcus lactis, Pediococcus acidilactici, Leuconostoc mesenteroides, and Leuc. pseudomesenteroides. A negligible amount of pollutant strains was found. Twenty-four LAB strains were isolated from the yoghurts and identified. Lb. delbrueckii subsp. bulgaricus strains were genotyped by randomly amplified polymorphic DNA–PCR (RAPD), multi-locus sequence typing (MLST), and pulse field gel electrophoresis (PFGE), which demonstrated their uniqueness and non-commercial origin. To estimate the bioactive metabolites produced by the accompanying microflora, yoghurts fermented by single LAB strains were analyzed using liquid chromatography and mass spectrometry (LC-MS). The fermented samples contained large amounts of free essential amino acids (arginine, citrulline, tryptophan, lysine, and histidine), the neuroprotector indole-3-propionic acid (IPA), and significant quantities of the cyclic antimicrobial peptides cyclo(phenylalanyl-prolyl) and cyclo(leucyloprolyl). The disclosure of these special qualities draws attention to the accompanying microflora as a source of potential probiotic strains that can fortify the yoghurts’ content with bioactive compounds.

Biogenic amine formation in fish roe in under the effect of drying methods and coating materials

The effects of drying methods (freeze-drying, fluidized bed-drying) and coating materials (gelatin, alginate, pectin) on the formation of biogenic amines (BAs) in fish roe were determined. The relationship between BAs content and free amino acid (FAA) profiles were monitored for 6 months. Lysine (282.5–385.0 mg/kg), leucine (258.5–319.1 mg/kg), phenylalanine (211.9–316.0 mg/kg) and isoleucine (208.8–312.8 mg/kg) were the most abundant free essential amino acids, whereas aspartic acid (498.3–742.6 mg/kg) and glutamic acid (420.9–620.7 mg/kg) constitute a big amount of nonessential FAAs in dried roes. High amino acid content was obtained in gelatin coated samples. The main BAs were putrescine, spermine and spermidine and all increased significantly (p < .01) with the storage time. High positive correlation was observed between free glutamic acid content and putrescine (0.91) and spermine (0.94) formation. Freeze-drying was successful in suppression the formation of BAs. Alginate and gelatin were better coating materials in terms of inhibiting microbiological growth. Practical applications The formation of BAs is a problem in seafood, especially during storage. Fish roe has abundant free amino acids such as lysine, leucine and phenylalanine that enables to form BAs. The main biogenic amines of trout roe were putrescine, spermine and spermidine. The formation of biogenic amines was hindered by freeze-drying method. Moreover, alginate and gelatin coatings were successful in suppression the microbial growth.

Bioconservation of iron and enhancement of antioxidant and antibacterial properties of chicken gizzard protein hydrolysate fermented by Pediococcus acidilactici ATTC 8042.

The poultry industry is one of the fastest growing sectors, and it generates considerable quantities of chicken gizzards (CG) every day. However, due to their hard texture and high microbial load, and due to cultural beliefs, they are not preferred by consumers. Chicken gizzards are a substantial source of proteins, iron, and other nutrients, which can be used effectively to produce nutraceuticals, rich in peptides (antioxidants and antibacterial), bio-iron, essential free amino acids, and fatty acids vital for human health. Lactic acid fermentation of CG by Pediococcus acidilactici ATTC 8042 increased the antioxidant activity of 2,2-diphenyl-1-picrylhydrazyl (DPPH), azino-bis (3-ethylbenzothiaziline-6-sulphonic acid) (ABTS), and ferric reducing antioxidant power (FRAP) by up to 26 times compared with unfermented CG (P < 0.05). The amount of hydrolysis and solvents (ethanol and water) used for extracting protein hydrolysates significantly affected the antioxidant properties. Moreover, fermented CG showed a negligible reduction in bio-iron (2-3%) compared with heat-processed CG (85 °C for 15 min), in which bio-iron was reduced by up to 20.3% (P < 0.05). The presence of unsaturated fatty acids such as C20:4 and C22:4 n-6 indicated a low level of lipid oxidation. Fermented CG, with its reasonably high antioxidant and antibacterial activity, together with a substantial amount of bio-iron and other nutritional components can serve as a functional food or feed additive to reduce oxidative stress and to treat iron deficiency. © 2020 Society of Chemical Industry.

Effect of High Hydrostatic Pressure Processing on the Chemical Characteristics of Different Lamb Cuts.

The non-thermal high-pressure processing (HPP) technique has been used to increase the shelf life of food without compromising their nutritional and sensory qualities. This study aims to explore the potential application of HPP on New Zealand lamb meat. In this study, the effect of HPP, at different pressure treatments (200–600 MPa) on eight different lamb meat cuts in terms of lipid oxidation, fatty acid and free amino acid content were investigated. In general treatments between 400 and 600 MPa resulted in higher oxidation values in eye of loin, flat, heel, and tenderloin cuts. Saturated and monounsaturated fatty acid content were significantly lower with HPP treatment of almost all cuts (except rump and heel cuts) at all pressures. Polyunsaturated fatty acid content was significantly lower in HPP-treated inside, knuckle, and tenderloin cuts at 600 MPa compared to control. Nine essential free amino acids (valine, leucine, isoleucine, methionine, phenylalanine, lysine, histidine, tyrosine and tryptophan), and eight non-essential free amino acids (alanine, glycine, threonine, serine, proline, aspartic acid, glutamic acids and ornithine) were identified in the lamb cuts. HPP increased the total free amino acid composition significantly compared to control at all pressures for almost all cuts except the inside and eye of loin cuts. This study suggests that higher pressure treatments (i.e., 400 and 600 MPa) resulted in higher TBARS oxidation levels. Additionally, significant decreases in saturated and monounsaturated fatty acids and increase free amino acid content were observed in the majority of HPP-treated samples compared to control.

Effects of DL-methionine and a methionine hydroxy analogue (MHA-Ca) on growth, amino acid profiles and the expression of genes related to taurine and protein synthesis in common carp (Cyprinus carpio)

In this trial, nine diets were formulated to investigate the effects of DL-methionine (DL-Met) and a methionine hydroxy analogue (MHA-Ca) on growth, amino acid profiles and the expression of genes related to taurine and protein synthesis in common carp. The basal diet was prepared without methionine supplementation and the other diets were formulated with 0.1%, 0.2%, 0.3% and 0.4% of DL-Met or MHA-Ca, respectively. After the eight-week feeding trial, fish fed with DL-Met or MHA-Ca supplemented diets had higher growth performance and feed utilization when compared with basal diet and two-way ANOVA showed the growth performance and feed utilization were significantly increased in fish fed DL-Met supplemented diets (P < 0.05). The concentrations of free amino acids in serum (Met, Leu, His, Lys, Val, Arg, Ile, Phe and Tau) and muscle (Tau) significantly increased as dietary DL-Met and MHA-Ca increased. Moreover, two-way ANOVA showed that taurine was higher in common carp fed with DL-Met diets compared with MHA-Ca diets. To find out how DL-Met and MHA-Ca affect taurine synthesis, genes involved in methionine degradation and taurine synthesis were further investigated. DL-Met or MHA-Ca supplementation decreased the expression of methionine adenosyltransferase II, alpha (MAT2A) and methionine synthase (MS) and increased the expression of the cysteine dioxygenase (CDO). Moreover, DL-Met supplementation significantly increased the expression of CDO and cysteine sulfinate acid decarboxylase (CSD) when compared with MHA-Ca supplementation. As for protein synthesis, the mRNA expression of mechanistic target of rapamycin (mTOR) in liver was not significantly different among all diet groups. But the expression of eukaryotic translation initiation factor 4E-Binding protein 1 (4EBP1), general control nonderepressible2 (GCN2) and asparagine synthetase (ASNS) in liver were significantly down-regulated as dietary DL-Met or MHA-Ca increased. Compared with MHA-Ca diets, the expression of S6 (ribosomal protein s6) and eIF4E (eukaryotic translation initiation factor 4E binding protein 2) were markedly elevated in DL-Met groups by the analysis of two-way ANOVA. This study indicated that dietary DL-Met or MHA-Ca supplement could increase free essential amino acids in serum, as well as improve taurine synthesis and protein synthesis in common carp. Multi-exponential regression analysis showed that MHA-Ca was less utilized by common carp than DL-Met with bioavailability values of 41% to 50% on weight-for-weight basis.

Antioxidant activity of organic sulfides from fresh Allium macrostemon Bunge and their protective effects against oxidative stress in Caenorhabditis elegans.

Long-stamen chive (Allium macrostemon Bunge; AMB), which is prevalent in the Wuling Mountain area of China, is a characteristic food of the nation. In the study, we evaluated the as-yet-unknown nutritional value and antioxidant activity of fresh AMB. The free amino acid content, volatile components, and free radical-scavenging capacity of isolated organic sulfides were analyzed to evaluate the qualitative and physiological properties of fresh AMB. The plant was found to be rich in free essential amino acids and contain multiple flavor-imparting amino acids. The organic sulfides showed an apparent free radical-scavenging activity in vitro. Furthermore, these sulfides alleviated oxidative stress in Caenorhabditis elegans. Notably, the organic sulfides isolated from AMB enhanced the activities of superoxide dismutase, catalase, and glutathione peroxidase; improved motility; and extended the lifespan in oxidative stress-affected nematodes. In conclusion, our study indicates that AMB is a nutritious vegetable with potential to be developed as a functional food. PRACTICAL APPLICATIONS: Long-stamen chive is a wild edible vegetable belonging to the genus Allium (A. macrostemon Bunge; AMB). However, its quality and physiological properties have not been comprehensively investigated. Herein, we analyzed the free amino acid content, composition of volatile compounds, and potential antioxidative properties of AMB. Our results indicated that AMB is rich in essential amino acids, making it a highly nutritious food. Further analysis indicated that AMB contains a high proportion of organic sulfides, which have been previously been shown to have antioxidative properties. Together, our findings indicate that AMB contains important bioactive components and can be developed as a functional food or health supplement. Furthermore, our findings will enhance public awareness regarding this wild resource and provide new directions for the research and development of natural products derived from it.

Manipulation of Dietary Amino Acids Prevents and Reverses Obesity in Mice Through Multiple Mechanisms That Modulate Energy Homeostasis.

Reduced activation of energy metabolism increases adiposity in humans and other mammals. Thus, exploring dietary and molecular mechanisms able to improve energy metabolism is of paramount medical importance because such mechanisms can be leveraged as a therapy for obesity and related disorders. Here, we show that a designer protein-deprived diet enriched in free essential amino acids can 1) promote the brown fat thermogenic program and fatty acid oxidation, 2) stimulate uncoupling protein 1 (UCP1)-independent respiration in subcutaneous white fat, 3) change the gut microbiota composition, and 4) prevent and reverse obesity and dysregulated glucose homeostasis in multiple mouse models, prolonging the healthy life span. These effects are independent of unbalanced amino acid ratio, energy consumption, and intestinal calorie absorption. A brown fat-specific activation of the mechanistic target of rapamycin complex 1 seems involved in the diet-induced beneficial effects, as also strengthened by in vitro experiments. Hence, our results suggest that brown and white fat may be targets of specific amino acids to control UCP1-dependent and -independent thermogenesis, thereby contributing to the improvement of metabolic health.

Rice OsLHT1 Functions in Leaf-to-Panicle Nitrogen Allocation for Grain Yield and Quality.

Proper allocation of nitrogen (N) from source leaves to grains is essential step for high crop grain yield and N use efficiency. In rice (Oryza sativa) grown in flooding paddy field, amino acids are the major N compounds for N distribution and re-allocation. We have recently identified that Lysine-Histidine-type Transporter 1 (OsLHT1) is the major transporter for root uptake and root-to-shoot allocation of amino acids in rice. In this study, we planted knockout mutant lines of OsLHT1 together wild-type (WT) in paddy field for evaluating OsLHT1 function in N redistribution and grain production. OsLHT1 is expressed in vascular bundles of leaves, rachis, and flowering organs. Oslht1 plants showed lower panicle length and seed setting rate, especially lower grain number per panicle and total grain weight. The concentrations of both total N and free amino acids in the flag leaf were similar at anthesis between Oslht1 lines and WT while significantly higher in the mutants than WT at maturation. The Oslht1 seeds contained higher proteins and most of the essential free amino acids, similar total starch but less amylose with lower paste viscosity than WT seeds. The mutant seeds showed lower germination rate than WT. Knockout of OsLHT1 decreased N uptake efficiency and physiological utilization efficiency (kg-grains/kg-N) by about 55% and 72%, respectively. Taken together, we conclude that OsLHT1 plays critical role in the translocation of amino acids from vegetative to reproductive organs for grain yield and quality of nutrition and functionality.

Effect of proteolytic starter culture isolated from Chinese Dong fermented pork (Nanx Wudl) on microbiological, biochemical and organoleptic attributes in dry fermented sausages

The effect of a proteolytic starter culture isolated from Nanx Wudl, on microbiological, biochemical and organoleptic attributes of dry fermented sausages was investigated during processing. Based on preliminary screening, the combination of Staphylococcus xylosus SX16 and Lactobacillus plantarum CMRC6, showing excellent proteolytic activity in vitro, was selected as the multi-strain starter (starter LS). For comparison, the single-strain starter culture of L. plantarum CMRC6 (starter LB) and non-inoculated control were also tested. During fermentation, lactic acid bacteria and staphylococci dominated the microbiota and suppressed the Enterobacteriaceae growth in LS-inoculated sausages. The addition of LS starter accelerated acidification and proteolysis during ripening, improving the contents of total free amino acids and several essential free amino acids (Phe, Ile and Leu). Volatile compounds analysis revealed that LS-fermented sausage showed the highest abundance of 3-methyl-1-butanol, probably due to the inoculated S. xylosus. The inoculation of LS starter improved the sensory properties of sausages, especially the flavor attribute. Therefore, S. xylosus SX16 and L. plantarum CMRC6 are promising candidates for inclusion as multi-strain starters in the manufacture of gourmet fermented dry sausage.

Compromised Glutamine - Glutamate Metabolism in a Pseudomonas Aeruginosa Induced Hyperdynamic Sepsis-Recovery Pig Model During an Anabolic Nutritional Intervention

Abstract Objectives Optimal feeding in patients recovering from sepsis is critical to preserve muscle mass. In sepsis, glutamine (Gln) is considered a conditional essential amino acid and low plasma level of its precursor glutamate (Glu), is associated with higher mortality. An essential amino acid (EAA) mixture restores protein anabolism in the early recovery phase of acute septicemia in the pig. However, it is unclear whether interorgan Glu-Gln kinetics is also improved. Therefore, we measured the interorgan kinetics of Glu-Gln during a nutritional intervention with a balanced free amino acid (TAA) or EAA mixture in the early recovery phase of acute septicemia in the pig. Methods In catheterized pigs (±25 kg), acute septicemia was present for 6 hours (Pseudomonas aeruginosa: 3e,8 CFU/ml/h IV). At t = 6 h, recovery was started by a single dose gentamycin (5 mg/kg) and intra-gastric continuous feeding of a balanced free TAA or EAA mixture (pig muscle profile, 31 mg N/kg bw/h, 30% daily intake and dextrose 781 mg/kg bw/h) for 6 hours. We studied 3 groups (Healthy: H-TAA n = 12; Sepsis: S-TAA n = 13, S-EAA n = 12) over the last 3 hours of the intervention by measuring arterial and venous plasma concentrations (expressed as mean[low, high 95%CI]) and organ net balances of the portal drained viscera (PDV), liver, kidneys and hindquarter (HQ, muscle). Statistics: Net balances were tested with Wilcoxon Signed Rank Test. Group comparisons with ANOVA. Significance: P &amp;lt; 0.05. Results Plasma concentrations : Gln was increased only in S-EAA (23 [14,32]%) group. In contrast, Glu substantially decreased in S-TAA and S-EAA (32[25,40]; 35[28,43]%) groups. Net PDV balance:Increased Gln uptake in S-EAA (P = 0.0020), but zero balance of Glu. Net HQ balance: Gln release was higher in S-TAA and S-EAA(P = 0.0028;0.0143). However, no changes in Glu uptake. Net liver balance: Gln uptake was higher in S-TAA and S-EAA (P = 0.0155;0.0056). Reduced Glu release in S-TAA (P = 0.0250). Net kidney balance: Zero balance for Gln, Glu uptake decreased in S-TAA (P = 0.0403). Conclusions In the present model of an early recovery of septicemia, interorgan Glu-Gln metabolism and Glu plasma levels are not restored by anabolic intervention, suggesting additional supplementation needs. Funding Sources NIH R01GM084447 and S10RR027047.

Effect of UV-C irradiation on the inactivation kinetics of oxidative enzymes, essential amino acids and sensory properties of coconut water.

The impact of ultraviolet light (UV-C) irradiation on oxidative enzymes [Polyphenol oxidase (PPO) and Peroxidase (POD)], free essential amino acids and sensory profile of coconut water were investigated. PPO and POD activities were lost to 94 and 93%, respectively of its original value at fluence level of 400mJ/cm2. Inactivation kinetics of both enzymes were fitted to nonlinear Weibull model with an increase in UV dosage with a high coefficient of determination (R2 > 0.97) and low root mean square error (RMSE < 0.06). No significant change was observed in all essential amino acids (p > 0.05) after UV-C treatment up to maximum delivered fluence of 400mJ/cm2. Sensory attributes of coconut water up to a treated UV-C fluence level of 200mJ/cm2 were well retained in terms of chosen descriptors (p > 0.05). This study allow to further investigate the development of UV-C light technology for inhibition of spoilage enzymes and prolonged shelf-life of low acid beverages.

Functional Chemical Components in Protaetia brevitarsis Larvae: Impact of Supplementary Feeds.

The goal of this study was to evaluate the influence of various supplementary feeds on the chemical composition and production of bioactive substances in Protaetia brevitarsis larvae. The primary feed—oak-fermented sawdust—was supplemented with a variety of substances, including aloe, apple, banana, sweet persimmon (S. persimmon) and sweet pumpkin (S. pumpkin). Crude protein and fat content were the highest in the control and S. pumpkin group, respectively. Supplementary feeds increased the content of unsaturated fatty acids, except in the group receiving S. pumpkin, in which oleic acid was the most abundant (58.2%–64.5%). Free essential amino acids in larvae receiving supplementary aloe were higher compared with the control group except for Lys and His. Polyphenol and flavonoid contents and the antioxidant activities of ABTS and DPPH were higher in all treated groups compared with the control group. Although supplementary feeds led to a decreased crude protein content in the treated larvae when compared with the control group, these treatments generally improved the levels of unsaturated fatty acids and antioxidative activity. Therefore, we suggest that among the supplementary foods tested, aloe is a better resource for P. brevitarsis based on crude protein content, free amino acids and other bioactive compounds such as unsaturated fatty acids and antioxidants.

The dynamic process of dietary soybean β-conglycinin in digestion, absorption, and metabolism among different intestinal segments in grass carp (Ctenopharyngodon idella).

The present study aimed to investigate the dynamic process of soybean β-conglycinin in digestion, absorption, and metabolism in the intestine of grass carp (Ctenopharyngodon idella). Fish fed with 80g β-conglycinin/kg diet for 7weeks, the intestinal digestive enzyme was extracted to hydrolyze β-conglycinin in vitro, the free amino acid and its metabolism product contents in intestinal segments were analyzed. The present study first found that β-conglycinin cannot be thoroughly digested by fish intestinedigestive enzyme and produces new products (about 60- and 55-kDa polypeptides). The indigestible β-conglycinin further caused the free amino acid imbalance, especially caused free essential amino acid deficiency in the proximal intestine but excess in the distal intestine. Moreover, these results might be partly associated with the effect of β-conglycinin in amino acid transporters and tight junction-regulated paracellular pathway. Finally, dietary β-conglycinin increased the content of amino acid catabolism by-product ammonia while decreased the amino acid anabolism product carnosine content in the proximal intestine and distal intestine. Thus, the current study first and systemically explored the dynamic process of β-conglycinin in digestion, absorption, and metabolism, which further supported our previous study that dietary β-conglycinin suppressed fish growth and caused intestine injure.

Role of light emitting diode (LED) wavelengths on increase of protein productivity and free amino acid profile of Spirulina sp. cultures

LEDs have specific wavelengths that can positively influence the production of microalga biomass and biomolecules of interest. Filling the gaps in the literature, this study evaluated the effect of different LED wavelengths and photoperiods on protein productivities and free amino acid (FAA) profile of Spirulina sp. LEB 18 cultures. The best protein productivity results were obtained in red and green LED cultures using integral and partial photoperiods, respectively. In these experiments, protein productivities increased 2 and 1.6 times, respectively, compared to the control culture using fluorescent light. Green LEDs in partial photoperiod provided also the highest concentrations of essential and non-essential FAA, about 1.8 and 2.3 times higher, respectively, than control cultures. LEDs showed to be a promising sustainable light source for increasing protein productivity and FAA concentration in Spirulina sp. LEB 18 cultures.

Nutritional Attributes and Nonvolatile Taste Components of Medicinally Important Wild False Earthstar Mushroom, Astraeus hygrometricus (Agaricomycetes), from India.

Fruiting bodies of Astraeus hygrometricus mushroom grown wild in the forests of Jharkhand, India were investigated for their proximate nutritional composition and taste imparting nonvolatile components. Fruiting bodies contained good amount of total carbohydrates (55.76%), reducing sugars (15.98%), protein (16.02%), and dietary fiber (39.78%) but were low in fat (3.5%), ash (3.8%), and energy (159.5 kcal). Fatty acids were represented by monounsaturated C18:1n9c oleic acid (4.59%) and saturated C16:0 palmitic acid (2.63%). In vitro digestibility of protein is an indicator of its availability to human body and A. hygrometricus has 33.2% in vitro digestibility. Among the minerals found (mg/100 g), potassium (K, 1930.0) was major mineral followed by calcium (Ca, 443.0), magnesium (Mg, 434.0), sodium (Na, 155.0), iron (Fe, 127.0), manganese (Mn, 16.0), and selenium (Se, 1.60). Pro-vitamin D2 (ergosterol) was also determined to be 1.09 mg/g. Analysis of soluble sugars indicated that mannitol (11.22 mg/g) was the major sugar alcohol conferring sweetness to the fruiting bodies. Among total free amino acids (8.20 mg/g), seven essential amino acids (3.9) and eight nonessential amino acids (4.3) were detected. Leucine (0.92) and tyrosine (0.98) were the major essential and nonessential amino acids, respectively. Aspartic (0.61) and glutamic acid (0.63) were also present in AH and responsible for its MSG like taste. Thus, A. hygrometricus is a good source of free essential amino acids and selenium, which is not synthesized by humans. Meaty flavor of the fruiting body of A. hygrometricus was mainly due to umami 5'-guanosine monophosphate (2.43 mg/g). Sweet taste and meaty flavor of the mushroom were due to nonvolatile taste components including soluble sugars and polyols, MSG like aspartic and glutamic acid, and umami 5'-nucleotide. Overall A. hygrometricus proved its edibility as a tasty and nutritional food.

Analysis of Nutritional Components and Antioxidant Activity in Vitro of Extracts from Ganoderma resinaceum

In order to further explore the nutritional components and antioxidant capacity of G. resinaceum extract,G. lucidum was used as a control in this study. First,distilled water and 55% ethanol were used to extract the corresponding water extracts and alcohol extracts,and then the total sugar and total triterpene content in the four extracts were determined by the phenol-sulfuric acid method and the vanillin-glacial acetic acid method,respectively. Next the content of free amino acids was determined by the L-8900 automatic amino acid analyzer. Finally,the 2,2'-Azinobis-(3-ethylbenzthiazoline-6-sulphonate)(ABTS),1,1-diphenyl-2-picrylhydrazyl(DPPH),and hydroxyl radical scavenging capacity of 4 kinds of extracts were measured. The results showed that the total sugar content in the water extract of G. lucidum and G. resinaceum were significantly higher than the corresponding alcohol extract(P 0.05). The content of total triterpenes in alcohol extracts of G. resinaceum was significantly higher than that of the other three extracts(P<0.05),reaching 25.37 mg/g,but the triterpene content of the water extract was the lowest,only 1.30 mg/g. The highest content of free essential amino acid in G. resinaceum water extract was 45.542 mg/g,while the content of G. lucidum water extract was the lowest(2.381 mg/g). G. resinaceum had the highest scavenging rates of ABTS,DPPH and hydroxyl radicals,which were 54.48%,24.42% and 10.32%,respectively. It indicated that G. resinaceum had strong antioxidant capacity. This study can provide a theoretical basis for the further development and application of G. resinaceum.

Increasing phosphate inhibits cadmium uptake in plants and promotes synthesis of amino acids in grains of rice

Technologies for cleaner production of rice in cadmium (Cd) contaminated field are being explored worldwide. In order to investigate the inhibition mechanism of phosphate on Cd transport in soil-plant system, controlled experiments were performed in this study. Experimental results showed that Cd levels in roots, flag leaves, rachises and grains of rice plants (Oryza sativa L.) were significantly reduced by supplement of 0.5–2.5 g kg−1 calcium magnesium phosphate fertilizer (CMP). Path coefficient analysis revealed that phosphorous had significant negative direct effect on Cd, but positive indirect effect on essential and non-essential amino acids. Applying 2.5 g kg−1 CMP made the Cd concentration decreased by 45.7% while free essential and non-essential amino acids increased by 28.0–28.6% in grains. Levels of the branched-chain amino acids in grains were much higher than other essential amino acids, and increased with the amount of CMP fertilization. After application of CMP, pH of soil solution and thickness of the iron plaque around roots increased significantly. Spectra from X-ray photoelectron spectrometer (XPS) showed that content of N, P and Fe increased apparently, C, O and Ca had no change, while S decreased by 74.2% in roots after application of 2.5 g kg−1 CMP. Meanwhile, Cd concentration in protoplasts of root cells decreased by 39.5–80.1% with the increase of CMP. These results indicate that application of CMP can effectively inhibit Cd accumulation in root protoplasts by promoting iron plaque formation on the root surface, reduce Cd concentration and increase free amino acids in rice grains.

Serra da Estrela cheese's free amino acids profiles by UPLC-DAD-MS/MS and their application for cheese origin assessment.

Serra da Estrela cheese is a high-value Portuguese Protected Designation of Origin cheese, produced with raw ewe milk. Thus, information regarding its composition is of utmost relevance for both consumers and certified producers. In this work, the chromatographic profiles of free amino acids in cheeses (45 days of maturation, 6 producers located in 5 municipalities and produced from November 2017 to March 2018) were established by UPLC-DAD-MS/MS. The proposed method allowed detecting 19 free amino acids and cystine with overall limits of detection and quantification lower than 44 μmol/L (1.4 mg/100 g cheese, wet matter) and than 134 μmol/L (4.2 mg/100 g cheese, wet matter), respectively. In all cheeses, 17 free amino acids were quantified including 8 essential amino acids (histidine, leucine-isoleucine, lysine, methionine, phenylalanine, threonine, tryptophan and valine) and 9 non-essential amino acids (arginine, asparagine, aspartic acid, cysteine, glutamic acid, glutamine, proline, serine and tyrosine). The amounts of the free amino acids, essential free amino acids, branched chain free amino acids (leucine, isoleucine and valine) plus the free amino acids ratios (mg/g protein) were further used to identify the producer of Serra da Estrela cheeses. Linear discriminant analysis coupled with the simulated annealing variable selection algorithm was used allowing the correct classification of 96% and 90 ± 8% of the samples, for leave-one-out and repeated K-fold cross-validation procedures, respectively. The satisfactory predictive performance pointed out the possibility of using cheeses' amino acids profiles as origin biomarkers for authenticity control, warranting the correctness identification of the cheese producer/brand, which is quite relevant for ensuring the consumer confidence and satisfaction when purchasing this high-value dairy food.