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Introduction: Distinguishing and categorizing the origin of garlic are highly significant, considering its widespread use as a flavoring agent. With billions of dollars annually in global trade, garlic is frequently susceptible to fraudulent practices. Methodology: Paper spray ionization mass spectrometry (PS‐MS) was employed to quickly analyze garlic samples from distinct geographic origins: China and Brazil. The so‐generated PS‐MS data were treated with metabolomic multivariate approaches, and the garlic samples from these different geographic regions were easily discriminated. Results: Brazilian garlic was characterized to contain higher levels of amino acids, such as arginine, proline, and valine, and organosulfur compounds, such as allicin, alliin, and l‐γ‐glutamil‐S‐allyl‐l‐cysteine, compared to Chinese garlic. The PS‐MS data were treated employing multivariate approaches, typically used in the metabolomics field, and this protocol was promptly able to discern among both types of samples. Conclusion: Hence, this combined strategy holds promise not only as an effective tool for the authentication of the geographical origin of garlic but also as a powerful means for biomarker discovery. [ABSTRACT FROM AUTHOR]

Luminescent carbon nanoparticles, such as carbon quantum dots (CQDs) and graphene quantum dots (GQDs), are increasingly utilized for sarcosine detection due to their exceptional water permeability, sustained luminescence, and biocompatibility. Sarcosine as a biomarker holds significance for therapeutic purposes and disease identification. Carbon‐based sensors offer eco‐friendliness, recyclability, and affordability, making them sustainable for sensing applications across various domains. Despite the widespread use of standard sensors for sarcosine measurement, they face limitations. This paper presents a focused review of recent developments in biosensors utilizing luminescent carbon quantum dots and graphene quantum dots for sarcosine detection. Key processes are characterized by their selectivity and sensitivity to different forms of sarcosine and interfering substances like metallic ions and amino acids. The significant reaction mechanisms and detection methods for sarcosine are outlined and compared. Additionally, the challenges in developing functionalized CQDs and GQDs for further investigation are explored. In summary, luminescent carbon nanoparticles offer a promising avenue for sarcosine detection, addressing limitations of standard sensors through their cost‐effectiveness, sensitivity, and rapid response, thus holding potential for diverse sensing applications. [ABSTRACT FROM AUTHOR]

Amines, crucial components in various industries, play a pivotal role in the synthesis of pharmaceuticals, agrochemicals, and specialty chemicals. Recognizing the environmental impact of conventional methods for their preparation, our study centers on the utilization of abundantly available natural molecules, specifically amino acids, as precursors for short chain amine synthesis. This paper focuses on the biocatalyst, L‐valine decarboxylase from Streptomyces viridifaciens (VlmD), delving into the substrate scope, catalytic activity, and cost‐effective scalability of an enzymatic process for amine synthesis. Additionally, we investigate the feasibility of immobilizing VlmD, aiming to pave the way for its effective use in industrial applications. Our study exploits the SpinChem system and provides a comprehensive understanding of the potential and limitations of this biocatalyst. Notably, our yields for key amines (8.42 g ⋅ d−1 for isobutylamine, 5.23 g ⋅ d−1 for isoamylamine, 5.16 g ⋅ d−1 for (S)‐2‐methylbutylamine, 3.78 g ⋅ d−1 for 3‐(methylthio)propylamine, and 10.52 g ⋅ d−1 for (R)‐1‐amino‐2‐propanol) demonstrate the process efficiency and potential for industrial scalability. [ABSTRACT FROM AUTHOR]

This paper reports the construction of racemic and enantiopure (D‐ and L‐) fluorene and fluorenone‐based novel unnatural amino acid derivatives. The Pd(II)‐catalyzed bidentate directing group‐aided arylation of prochiral β‐C(sp3)‐H bonds in racemic, enantiopure carboxamides of amino acids with iodofluorenes was reported. The construction of novel examples of fluorene and fluorenone motifs containing amino acids comprising of norvaline, leucine, phenylalanine, norleucine, 2‐aminooctanoic acid derivatives having the anti‐stereochemistry (with good enantiopurity) was accomplished. The construction of bis fluorenyl alanine scaffolds and fluorenyl motif‐containing non‐α‐amino acid (aminoalkanoic acid) derivatives was also reported. Examples of removal of the directing group (8‐aminoquinoline) and phthalimide‐protecting group present in the fluorenyl‐based unnatural amino acid derivatives have been shown. Accordingly, fluorene motif‐based amino acid esters and free amino group‐containing unnatural amino acid derivatives were synthesized. The stereochemistry of the major (anti) diastereomers obtained via the prochiral β‐C(sp3)‐H arylation of norvaline, leucine, phenylalanine, norleucine, 2‐aminooctanoic acid derivatives was ascertained from the X‐ray structure of a representative compound. Fluorene‐ and fluorenone‐based motifs are vital skeletons in materials and medicinal chemistry research. Accordingly, this work is a contribution towards enriching the library of fluorene and fluorenone unnatural amino acid scaffolds. [ABSTRACT FROM AUTHOR]

Societal Impact Statement: The world is increasingly looking to plant‐based sources to meet its protein needs. Multiple factors are driving this progression, ranging from nutritional and ethical considerations to climate change and population growth. As a pulse crop, lentil is ideal to help meet this change in demand. However, plant‐based proteins have limiting amino acids and lower protein digestibility compared to animal‐based proteins. This research identifies genetic markers that can be used to accelerate breeding of protein quality traits in lentil to ultimately help meet the rising demand in high‐quality plant‐based protein and bolster global food and nutritional security. Summary: Lentil (Lens culinaris Medik.) contains ~25% high‐quality protein in addition to high concentrations of prebiotic carbohydrates and micronutrients, such as folate, iron, zinc, and selenium. As animal‐based protein's economic and environmental costs rise, plant‐based protein sources, such as lentil, will become increasingly important to global food systems. Consequently, evaluating and targeting protein quality traits for genomic‐assisted breeding is a valuable objective for lentil breeding programs.A diversity panel of 183 breeding lines was analyzed for protein quality traits, including amino acids and protein digestibility. Genotyping‐by‐sequencing (GBS) data were used to assess population structure and conduct genome‐wide association studies (GWAS). Genes in local linkage disequilibrium (LD) with significant single nucleotide polymorphism (SNP) markers were identified and categorized by homology.Protein quality traits showed a wide range of variation. Repeatability estimates were low to moderate across traits. Twelve traits were strongly correlated with each other (r >.7). Admixture analysis identified six ancestral subpopulations, which also demonstrated clustering in principal component analysis. Ten different traits had significant SNP associations; two loci were shared across multiple traits. Twenty‐seven candidate genes, including glutathione S‐transferase, protease family, and gibberellin 2‐beta‐dioxygenase genes, were identified.This paper identifies SNP markers associated with lentil protein quality traits. Once validated, these SNPs could accelerate lentil protein quality breeding efforts. By targeting lentil's limiting amino acids (methionine and cysteine) and protein digestibility through marker‐assisted selection, the nutritional value of lentil's protein content could be increased without the need to alter total protein content. [ABSTRACT FROM AUTHOR]

Six peptide toxins (Magi 1–6) were isolated from the Hexathelidae spider Macrothele gigas. The amino acid sequences of Magi 1, 2, 5 and 6 have low similarities to the amino acid sequences of known spider toxins. The primary structure of Magi 3 is similar to the structure of the palmitoylated peptide named PlTx-II from the North American spider Plectreurys tristis (Plectreuridae). Moreover, the amino acid sequence of Magi 4, which was revealed by cloning of its cDNA, displays similarities to the Na+ channel modifier δ-atracotoxin from the Australian spider Atrax robustus (Hexathelidae). Competitive binding assays using several 125I-labelled peptide toxins clearly demonstrated the specific binding affinity of Magi 1–5 to site 3 of the insect sodium channel and also that of Magi 5 to site 4 of the rat sodium channel. Only Magi 6 did not compete with the scorpion toxin LqhαIT in binding to site 3 despite high toxicity on lepidoptera larvae of 3.1 nmol/g. The Kis of other toxins were between 50 pM for Magi 4 and 1747 nM for Magi 1. In addition, only Magi 5 binds to both site 3 in insects (Ki=267 nM) and site 4 in rat brain synaptosomes (Ki=1.2 nM), whereas it showed no affinities for either mammal binding site 3 or insect binding site 4. Magi 5 is the first spider toxin with binding affinity to site 4 of a mammalian sodium channel. [Copyright &y& Elsevier]

1. A new diagonal etectrophoretic technique for determining the order of the lysine-containing tryptic peptides of a protein is described. The protein is converted into its trifluoracetyl derivative, digested enzymatically (or chemically), and the resulting peptides separated by paper electrophoresis. The paper is then treated with ammonia vapour, which re-exposes the ε-amino groups of the lysine residues, and submitted to a second electrophoresis at right angles to the first direction. Peptides containing lysine residues, together with the N-terminal peptide of the protein, are found to lie off a diagonal formed by all other peptides, whence they may be readily purified. A study of these peptides enables the order of the lysine-containing tryptic peptides in the protein to be deduced. 2. The technique has been successfully tested with insulin. 3. When the method was applied to porcine pepsin, the four tryptic peptides isolated were easily ordered and the carboxyl-terminal sequence of the protein shown to be Arg-Gln-Tyr-TyrThr-Val-Phe-Asp-Arg-Ala-Asn-Asn-Lys-Val-Gly-Leu-Ala-Pro-Val-Ala. The thee basic ammo acid residues in the molecule are thus found clustering towards the C-terminus of the polypeptide chain. 4. A common ancestral gene for porcine pepsin and bovine (calf) rennin is suggested by the close homology between the C-terminal sequents of the two proteins. [ABSTRACT FROM AUTHOR]

Summary: Maize grain is deficient in lysine. While the opaque2 mutation increases grain lysine, o2 is a transcription factor that regulates a wide network of genes beyond zeins, which leads to pleiotropic and often negative effects. Additionally, the drastic reduction in 19 kDa and 22 kDa alpha‐zeins causes a floury kernel, unsuitable for agricultural use. Quality protein maize (QPM) overcame the undesirable kernel texture through the introgression of modifying alleles. However, QPM still lacks a functional o2 transcription factor, which has a penalty on non‐lysine amino acids due to the o2 mutation. CRISPR/cas9 gives researchers the ability to directly target genes of interest. In this paper, gene editing was used to specifically target the 19 kDa alpha zein gene family. This allows for proteome rebalancing to occur without an o2 mutation and without a total alpha‐zein knockout. The results showed that editing some, but not all, of the 19 kDa zeins resulted in up to 30% more lysine. An edited line displayed an increase of 30% over the wild type. While not quite the 55% lysine increase displayed by QPM, the line had little collateral impact on other amino acid levels compared to QPM. Additionally, the edited line containing a partially reduced 19 kDa showed an advantage in kernel texture that had a complete 19 kDa knockout. These results serve as proof of concept that editing the 19 kDa alpha‐zein family alone can enhance lysine while retaining vitreous endosperm and a functional O2 transcription factor. [ABSTRACT FROM AUTHOR]

In this paper, the amino acid chiral ionic liquid (AACIL) was prepared with L‐phenylalanine and imidazole. It was characterized by CD, FT‐IR, 1H NMR, and 13C NMR spectrum. The chiral recognition sensor was constructed with AACIL and Cu(II), which exhibited different chiral visual responses (solubility or color difference) to the enantiomers of glutamine (Gln) and phenylalanine (Phe). The effects of solvent, pH, time, temperature, metal ions, and other amino acids on visual chiral recognition were optimized. The minimum concentrations of Gln and Phe for visual chiral recognition were 0.20 mg/ml and 0.28 mg/ml, respectively. The mechanism of chiral recognition was investigated by FT‐IR, TEM, SEM, TG, XPS, and CD. The location of the host‐guest inclusion or molecular placement has been conformationally searched based on Gaussian 09 software. [ABSTRACT FROM AUTHOR]

Synthetic therapeutic peptides are a complex and popular class of pharmaceuticals. In recent years, peptides with proven therapeutic activity have gained significant interest in the market. The determination of synthetic peptide enantiomeric purity plays a critical role in the evaluation of the quality of the medicine. Since racemization is one of the most common side reactions occurring in AAs or peptides, enantiomeric impurities such as D‐isomers can form during the peptide synthesis or can be introduced from the starting materials (e.g., AAs). The therapeutic effect of a synthetic or semi‐synthetic bioactive peptide molecule depends on its AA enantiomeric purity and secondary/tertiary structure. Therefore, the enantiomeric purity determination for synthetic peptides is supportive for interpreting unwanted therapeutic effects and determining the quality of synthetic peptide therapeutics. However, enantiomeric purity analysis encounters formidable analytical challenges during chromatographic separation, as D/L isomers have identical physical–chemical properties except stereochemical configuration. To ensure peptides AA stereochemical configuration whether in the free or bound state, sensitive and reproducible quantitative analytical method is mandatory. In this regard, numerous analytical techniques were emerged for the quantification of D‐isomeric impurities in synthetic peptides, but still, very few reports are available in the literature. Thus, the purpose of this paper is to provide an overview of the importance, regulatory requirements, and various analytical methods used for peptide enantiomeric purity determination. In addition, we discussed the available literature in terms of enantiomeric impurity detection, common hydrolysis procedural aspects, and different analytical strategies used for sample preparation. [ABSTRACT FROM AUTHOR]

In the present paper, a biosensor is proposed with a split gate dielectric modulated bottom gate top contact organic thin‐film transistor. A cavity is marked below gate metal for enhancing sensitivity in biomedical applications. The organic thin‐film transistors‐based biosensors have shown applications over advanced biosensing platforms due to their intrinsic ability to transfer and amplify received biological signals into respective electrical signals. Immobilizing the biomolecules inside the cavity generates changes in surface potential. The analysis is carried out via different performance metrics that directly affect device electrical characteristics such as a change in spacer length applied voltages (Vgs and Vds) as well as channel material. After modeling, the device output characteristics are compared corresponding to simulated outcomes that validated our results. The proposed model structure is categorized by dividing it into different sections. Each categorized section's surface potential is further evaluated via 1‐ and 2‐dimensional Poisson's equation. The simulations to recreate biomolecules in terms of dielectric constant and charge density are done in the Silvaco ATLAS tool. The maximum value of sensitivity of proposed biosensor is around 300 in the case of charged biomolecule detection. [ABSTRACT FROM AUTHOR]

The development of water‐soluble hosts for the selective recognition of aromatic amino acids is highly desirable and may serve as a tool to facilitate drug discovery and enable fabrication of sensors for point‐of‐care monitoring in the context of phenylketonuria disease. This paper presents the synthesis and characterization of a water‐soluble molecular cleft which is demonstrated to selectively bind aromatic amino acid guests over other amino acids in aqueous medium, favoring ʟ‐Trp over ʟ‐Phe and ʟ‐Tyr by a factor of approximately five. Host/guest‐interaction forces were studied by 1H‐NMR titrations complemented by fluorescence titrations and isothermal titration calorimetry. The here presented results provide a starting point for future optimizations in our efforts to selectively identify and quantify individual aromatic amino acids in aqueous medium. [ABSTRACT FROM AUTHOR]

Molecular biological studies confirmed that two glutamate dehydrogenase isozymes (hGDH1 and hGDH2) of distinct genetic origin are expressed in human tissues. hGDH1 is heat-stable and expressed widely, whereas hGDH2 is heat-labile and specific for neural and testicular tissues. A selective deficiency of hGDH2 has been reported in patients with spinocerebellar ataxia. We have identified an amino acid residue involved in the different thermal stability of human GDH isozymes. At 45°C (pH 7.0), heat inactivation proceeded faster for hGDH2 (half life=45 min) than for hGDH1 (half-life=310 min) in the absence of allosteric regulators. Both hGDH1 and hGDH2, however, showed much slower heat inactivation processes in the presence of 1 mM ADP or 3 mM L-Leu. Virtually most of the enzyme activity remained up to 100 min at 45°C after treatment with ADP and L-Leu in combination. In contrast to ADP and L-Leu, the thermal stabilities of the hGDH isozymes were not affected by addition of substrates or coenzymes. In human GDH isozymes, the 443 site is Arg in hGDH1 and Ser in hGDH2. Replacement of Ser by Arg at the 443 site by cassette mutagenesis abolished the heat lability of hGDH2 with a similar half-life of hGDH1. The mutagenesis at several other sites (L415M, A456G, and H470R) having differences in amino acid sequence between the two GDH isozymes did not show any change in the thermal stability. These results suggest that the Ser443 residue plays an important role in the different thermal stability of human GDH isozymes. [Copyright &y& Elsevier]

The process of growth, development, and reproduction cannot take place in a live body without the presence of amino acids (AAs) since they are necessary for appropriate functioning. Detection of AAs in pharmaceutical and food samples is required to ensure quality, quantity, and efficacy. The AAs generally do not contain chromophores; hence their chromatographic analysis requires derivatization. The research papers published in the last few years were used to compile this manuscript. This manuscript covers various analytical, bioanalytical, and electrochemical approaches used in the identification of AAs. The analytical techniques like high‐performance liquid chromatography, ultra‐performance liquid chromatography, etc., and the hyphenated analytical techniques like liquid chromatography‐mass spectrometry, ultra‐performance liquid chromatography‐electrospray tandem mass spectrometry, and hydrophilic interaction ultra‐performance liquid chromatography are also discussed. This manuscript also briefly outlines the electrochemical analytical techniques including sensors and biosensors. This review article will be useful to the researcher working in the area of the development of analytical techniques for the detection of AAs. [ABSTRACT FROM AUTHOR]

Leonurus japonicus Houtt (LJH) is a bulk medicinal material commonly used in clinical practice, but its complex constituents have not been completely understood, posing challenges to pharmacology, pharmacokinetic research, and scientific and rational drug use. As a result, it is critical to develop an efficient and accurate method for classifying and identifying the chemical composition of LJH. In this study, ultra‐performance liquid chromatography‐quadrupole electrostatic field‐orbital trap high resolution mass spectrometry (UPLC‐Q‐Orbitrap‐MS) was successfully established, along with two data post‐processing techniques, characteristic fragmentations (CFs) and neutral losses (NLs), to quickly classify and identify the chemical constituents in LJH. As a result, 44 constituents of LJH were identified, including four alkaloids, 20 flavonoids, two phenylpropanoids, 17 organic acids, and one amino acid. The method in this paper enables classification and identification of chemical compositions rapidly, providing a scientific foundation for further research on the effective and toxic substances of LJH. [ABSTRACT FROM AUTHOR]

In this paper, two new amino acid imidazole ionic liquids IL‐3 and IL‐4 were synthesized for the first time, and their separation performance as the stationary phase for capillary gas chromatography (GC) was tested. The statically coated IL‐3 and IL‐4 capillary columns exhibited moderate to high polarity, and achieved the column efficiency of 2242 plates/m and 2487 plates/m respectively determined by n‐octanol at 120 °C. Importantly, the IL‐3 and IL‐4 columns exhibited excellent separation capability for analytes with varying polarity, including n‐alkanes, arenes, esters, alcohols, bromoalkanes, halogenobenzenes, and halogenated anilines. In addition, the IL‐3 and IL‐4 columns presented high selectivity and separation capability for positional, structural and cis‐/trans‐isomers. In particular, they showed high separation performance of the chloroaniline, bromaniline, iodoaniline and xylidine isomers as an important environmental pollutant. The IL‐3 and IL‐4 columns displayed advantageous resolving capability over the commercial HP‐35 column for aromatic amine isomers, and the separation performance of IL‐4 with long carbon chain was better than that of IL‐3. Moreover, it was applied to determine isomer impurities in real samples, and showing huge potential in GC applications. This work demonstrates the potential of the amino acid imidazole ionic liquids as a new type of stationary phase in GC separations. [ABSTRACT FROM AUTHOR]

Cashew (Anacardium occidentale) has received both local and international recognition due to its expanding production capacity, trading, and nut utilization. The cashew apple, which forms about 90% of the total fruit weight, is left on the farmers' fields as agricultural waste owing to limited knowledge of its health benefits, a lack of technical know‐how and processing equipment, and its high perishability and astringent taste. Numerous studies have been conducted exploring the nutrients and contribution of the apple to human nutrition. This paper reviewed recent articles on the nutritional composition and health benefits of cashew apples for easy accessibility and readership. Cashew apple contains good amounts of vitamin C, sugars (fructose and sucrose), fibers, flavonoids, carotenoids, total polyphenols, volatile components, flavanols, amino acids, and minerals, such as potassium, magnesium, sodium, and iron, which are good for maintaining strong immunity, scavenging free radicals, neuropathic functioning, cardiac functioning, and maintenance of body and skin integrity. Cashew apple is associated with weight loss, and is good for diabetic patients due to its high content of flavonoids (myricetin and quercetin). Consumption of cashew apple and its value‐added products confer good health, therapeutic effects in the management of diabetics and cardiovascular diseases, and also ensure food and nutrition security. It is hoped that this review will contribute significantly to the expanding body of knowledge aimed at promoting cashew apple utilization globally. [ABSTRACT FROM AUTHOR]

LINKED CONTENT: This article is linked to Hey et al paper. To view this article, visit https://doi.org/10.1111/apt.17917 [ABSTRACT FROM AUTHOR]

BACKGROUND: The aim of this study was to investigate the effects of different smoking methods on sensory properties, free amino acids (FAAs) and volatile compounds (VCs) of bacon. Descriptive analysis was performed using a highly trained panel (n = 9) to evaluate four bacons in sextuplicate. VCs of bacons were analyzed using solid‐phase microextraction (SPME) coupled with gas chromatography–mass spectrometry (GC–MS). RESULTS: Bacons were significantly different in sensory properties (P < 0.05). Wood smoked bacon (WSB) had a higher smoky and fatty aroma, liquid smoked bacon (LSB) had a higher red color intensity and yellow color intensity, and paper smoked bacon (PSB) had an outstanding texture. Different smoking methods resulted in an increase in total FAAs content, of which paper smoking was significantly higher than the others (P < 0.05). Also, a total of 59 volatile flavor compounds were identified for bacons, aldehydes were the most abundant groups of compounds. Principal component analysis (PCA) can effectively separate the bacons that underwent different smoking methods. CONCLUSION: The aldehydes and hydrocarbons with high content in PSB improved the overall taste intensity. The color in the sensory attributes was more obvious after LSB processing. The phenols and aromatic hydrocarbons in WSB contributed significantly to the pleasant properties (smoky, fatty). © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

In this paper, Garphos with different substituents were employed as chiral extractants to enantioseparate racemic amino acid and mandelic acid. The influences of metal precursors, pH of aqueous solution, Garphos‐metal concentration, extraction temperature, and substituent effect on extraction were investigated. The results indicated that the substituent groups significantly affected the π‐π interaction between extractant and substrate. And the separation factors (α) for Garphos could be remarkably improved by regulating substituent groups. Garphos‐II‐Pd, Garphos‐VI‐Pd, Garphos‐III‐Pd, Garphos‐I‐Cu, Garphos‐VI‐Cu, and Garphos‐V‐Pd were the most efficient extractants for phenylalanine (Phe), homophenylalanine (Hphe), 4‐nitrophenylalanine (Nphe), 3‐chlorophenylglycine (Cpheg), mandelic acid (MA), and 2‐chlormandelic acid (CMA) with α values of 2.40, 2.37, 5.37, 1.59, 5.98, and 3.69, respectively. This work provided an important reference for the design of efficient chiral extractants in future work. [ABSTRACT FROM AUTHOR]

Lawsone is a 2‐substituted‐1,4‐naphthoquinone derivative, which has been proposed as an alternative to the reagents currently used for fingermark detection on porous surfaces. 2‐substituted‐anthraquinones, which contain an additional conjugated benzene ring, have a similar chemical structure to that of lawsone. In this study, a new series of 2‐substituted‐1,4‐naphthoquinones and 2‐substituted‐1,4‐anthraquinones were synthesized and completely characterized by1H NMR,13C NMR, IR, and HPLC‐TOF/MS analyses. All newly synthesized 2‐substituted‐1,4‐quinones were investigated for their ability to develop latent fingermarks on porous surfaces, and this ability was compared with that of lawsone. Each fingermark developed was graded using an established method; thus, quantitative data were attributed to each fingermark. It has been demonstrated that the 1,4‐quinones react with amino acids present in latent fingermarks on selected paper surfaces to produce faint yellow‐orange impressions, which exhibit strong photoluminescence when illuminated with a forensic light source at 440 nm and observed through a red filter. None of the compounds caused background darkening. The results obtained were generally similar to those of lawsone, however, 8‐dibromo‐2‐(propylamino)naphthalene‐1,4‐dione and 5,8‐dibromo‐2‐(propylthio)naphthalene‐1,4‐dione yielded better results for copier paper and colored (blue) copier paper used in this analysis. To the best of our knowledge, this is the first study to examine the role of 1,4‐anthraquinone derivatives as potential fingermark development reagents. The results indicate that 1,4‐quinones have a potential to be used as reagents for enhancement of latent fingermarks. [ABSTRACT FROM AUTHOR]

Dried blood spots (DBS), created by applying and drying a whole blood sample onto filter paper, provide a simple and minimally invasive procedure for collecting, transporting, and storing blood. Because DBS are ideal for use in field and resource‐limited settings, we aimed to develop a simple and accurate DBS‐based approach for assessing mercury (Hg) exposure and dietary carbon sources for landlocked Arctic char, a sentinel fish species in the Arctic. We collected liquid whole blood (from the caudal vein), muscle, liver, and brains of Arctic char (n = 36) from 8 lakes spanning a Hg gradient in the Canadian High Arctic. We measured total Hg concentrations ([THg]) of field‐prepared DBS and Arctic char tissues. Across a considerable range, [THg] of DBS (0.04–3.38 μg/g wet wt) were highly correlated with [THg] of all tissues (r2 range = 0.928–0.996). We also analyzed the compound‐specific carbon isotope ratios (expressed as δ13C values) of essential amino acids (EAAs) isolated from DBS, liquid whole blood, and muscle. The δ13C values of 5 EAAs (δ13CEAAs; isoleucine [Ile], leucine [Leu], phenylalanine [Phe], valine [Val], and threonine [Thr]) from DBS were highly correlated with δ13CEAAs of liquid whole blood (r2 range = 0.693–0.895) and muscle (r2 range = 0.642–0.881). The patterns of δ13CEAAs of landlocked Arctic char were remarkably consistent across sample types and indicate that EAAs are most likely of algal origin. Because a small volume of blood (~50 µL) dried on filter paper can be used to determine Hg exposure levels of various tissues and to fingerprint carbon sources, DBS sampling may decrease the burdens of research and may be developed as a nonlethal sampling technique. Environ Toxicol Chem 2020;39:893–903. © 2020 SETAC [ABSTRACT FROM AUTHOR]

Aim: There is no standardised interventional approach to preventing or treating sarcopenia in older adults in hospital. The aim of this review was to systematically identify and synthesise the effects of nutritional interventions on markers of sarcopenia in hospitalised patients aged 65 years and older. Methods: Four databases were searched using terms for intervention, population and setting. Eligibility screening of title and abstract and then full‐text papers was competed in duplicate, independently. The final included papers were assessed for quality, and outcome data extracted independently and in duplicate. Outcome data were synthesised by meta‐analysis, where possible, or narratively. Results: Seven hundred and thirty‐two articles were screened for eligibility yielding six studies for inclusion. All studies provided oral nutritional support that aimed to increase protein intake ranging from an additional 10 to 40 g/d, each with a unique formulation of amino acids and/or micronutrients; three studies combined nutritional intervention with an enhanced physical activity program. Five studies measured hand grip strength, the mean difference was 1.97 kg (95% CI 0.55‐3.39, P =.006) greater in the intervention group (n = 166) compared with control group (n = 165). Assessment of muscle mass and activities of daily living were heterogeneous and the changes inconsistent between studies. Conclusions: Few studies inform nutritional management of inpatients with sarcopenia or at risk of sarcopenia. High quality, large intervention trials are needed urgently to identify the optimal nutrition and physical activity intervention combinations to manage sarcopenia in older hospitalised adults. These studies need to include outcome measures of physical function and muscle quality. [ABSTRACT FROM AUTHOR]

Cardiovascular diseases (CVD) are a significant and growing burden on global health services, and it is now accepted that impairment of vascular function represents a major preliminary step in the development of CVD. There is considerable interest in identifying both causal factors of impaired vascular function, as well as related nutritional factors that may lower the risk of developing CVD, and food‐derived bioactive peptides and amino acids have emerged as one such area. Dairy foods contain two groups of proteins, whey proteins and caseins, which represent a rich source of bioactive peptides that are released during food processing and/or digestion. These peptides have a number of physiological activities including the potential to reduce blood pressure. Research, including acute and longer‐term randomised controlled trials, animal models and in vitro models has demonstrated the potential impact of dairy proteins on vascular function. The purpose of this paper is to narratively review the evidence, primarily from randomised controlled trials, examining the effects of whey proteins, their peptides and amino acids on vascular function and related issues including blood pressure. In addition, it will explore the potential underlying mechanisms responsible for these effects. It concludes that there is increasing evidence that whey proteins, and notably the bioactive peptides and amino acids released during their digestion, can have beneficial effects on aspects of vascular function and thus contribute to CVD risk reduction. It also highlights a number of beneficial effects of whey proteins including those on blood pressure, arterial stiffness, nitric oxide production and inflammation. [ABSTRACT FROM AUTHOR]

Introduction: The MHC‐peptide interaction has a subtle influence on host resistance to virus. This paper aims to study the relationship between MHC‐peptide interaction and MHC‐related virus‐resistance. Methods: By 3D homology modeling, the structure of chicken BF2 molecule BF2*0201 (PDB code: 4d0d) was studied and compared with the known structures of BF2 molecule BF2*0401 (PDB code: 4e0r) to elucidate the characteristics of BF2*0201‐binding antigenic peptides. Results: The results show that due to the amino acid difference between the two binding groove of 4e0r and 4d0d, the size of the binding groove of the two are 1130 ų and1380 ų respectively, indicating the amino acid species that 4e0r binding peptide has lower selectivity than 4d0d; and because of large side chain conformation of Arg (especially Arg111) of 4e0r replaced by small side chain Tyr111 of 4d0d, the volume of central part of the binding groove of 4d0d is obviously larger than that of 4e0r, indicating that the restrictive of binding antigenic peptides for 4d0d is narrower than that of 4e0r; and on account of the chargeability of the binding groove of the two are different, namely the binding groove chargeability of 4e0r (strong positive polarity) and 4d0d (weak negative polarity). Conclusion: There are generally more peptides presented by the BF2 of B2 haplotype than by that of B4 haplotype, leading to more resistance of B2 than that of B4 to virus. [ABSTRACT FROM AUTHOR]

Summary: Yeast extract (YE) is a kind of umami additives used in fermented condiments, it also has special yeasty flavour (YF), which is not widely accepted by some consumers. In this paper, the technology of mixed microbial transformation was applied to eliminate or cover up YF during mixed fermentation. FG10, which is produced by Hubei Angel Yeast Co. Ltd, is a kind of YE that has the distinctive YF and has been applied to the market. It had good sensory evaluation after 6 h with Saccharomycopsis fibuligera and Lactococcus lactis. At 6 h, compared with single fermentation, the number of bacteria of L. lactis was enhanced by 34.28%, and the number of bacteria of S. fibuligera was reduced by 47.93%. The yeasty flavoured substances propionic acid and butyric acid were completely removed. The result of GC‐MS showed that acetal, phenyl acetaldehyde, 2,4‐dimethylbenzaldehyde, benzaldehyde, isoamyl alcohol, 5‐methyl‐2‐furan methanol, phenylethanol were generated or increased. Furthermore, the amino acids of YE were significantly different after fermentation by different microorganisms (P < 0.05), The flavour compounds and amino acids in YE before and after fermentation had closely correlation (r = 0.94), the consumption of amino acids in mixed fermentation promoted the variety of corresponding flavour compounds, which boosted the formation of free YF YE. In addition, taste substances lactic acid generated 6.27 ± 0.115 g L−1 and nucleotides improved 15.05%, which were beneficial to natural YF free seasoning with YE as raw material. [ABSTRACT FROM AUTHOR]

Recently, we presented a strategy for packaging peptides as side‐chains in high‐density brush polymers. For this globular protein‐like polymer (PLP) formulation, therapeutic peptides were shown to resist proteolytic degradation, enter cells efficiently and maintain biological function. In this paper, we establish the role charge plays in dictating the cellular uptake of these peptide formulations, finding that peptides with a net positive charge will enter cells when polymerized, while those formed from anionic or neutral peptides remain outside of cells. Given these findings, we explored whether cellular uptake could be selectively induced by a stimulus. In our design, a cationic peptide is appended to a sequence of charge‐neutralizing anionic amino acids through stimuli‐responsive cleavable linkers. As a proof‐of‐concept study, we tested this strategy with two different classes of stimuli, exogenous UV light and an enzyme (a matrix metalloproteinase) associated with the inflammatory response. The key finding is that these materials enter cells only when acted upon by the stimulus. This approach makes it possible to achieve delivery of the polymers, therapeutic peptides or an appended cargo into cells in response to an appropriate stimulus. [ABSTRACT FROM AUTHOR]

Monoalkylated derivatives of the unusually polar all‐cis 2,3,4,5,6‐ pentafluorocyclohexyl (Janus face) motif are prepared starting from an aryl hydrogenation of 2,3,4,5,6‐ pentafluorophenylacetate methyl ester 15. The method used Zeng's Rh(CAAC) carbene catalyst 4 in the hydrogenation following the protocol developed by Glorius. The resultant Janus pentafluorocyclohexylacetate methyl ester 16 was converted to the corresponding alcohol 18, aldehyde 13, bromide 29 and azide 14 through functional group manipulations, and some of these building blocks were used in Ugi‐multicomponent and Cu‐catalysed click reactions. NBoc protected pentafluoroarylphenylalanine methyl ester 35 was also subject to an aryl hydrogenation, and then deprotection to generate the Janus face β‐pentafluorocyclohexyl‐alanine amino acid 15, which was incorporated into representative members of an emerging class of candidate antiviral compounds. Log P measurements demonstrate that the all‐cis 2,3,4,5,6‐pentafluorocyclohexyl ring system is more polar than a phenyl ring. In overview the paper introduces new building blocks containing this Janus ring and demonstrates their progression to molecules typically used in bioactives discovery programmes. [ABSTRACT FROM AUTHOR]

The article presents a list of papers to be published in forthcoming issue of the "British Journal of Haematology." Some of them are: "Pancytopenia in Hereditary Haemorrhagic Telangiectasia," "Acute Lymphoblastic Leukaemia Relapsing With Solid Hepatic Tumours After Bone Marrow Transplantation," "Inhibitors in Congenital Coagulation Disorders," "The Role of Granulocyte Transfusions in Neutropenic Patients," "TAFI Polymorphisms at Amino Acids 147 and 325 are not Risk Factors for Cerebral Infarction."

Cysteine (Cys) is an amino acid found in the body that exerts a good antioxidant effect. Sensitive detection of Cys has far‐reaching significance both in the cosmetics industry and biochemical reports. This paper showed that Fe‐MIL‐88NH2. Fe‐MIL‐88NH2 particles were prepared using solvothermal synthesis and their structure was determined using powder X‐ray diffraction, FT‐IR, electron microscopy, as well as N2 adsorption‐desorption measurements. Because of the large channels present in the frame, Fe‐MIL‐88NH2 quickly removed hazardous cationic dyes from water within several minutes. Luminescence tests showed Fe‐MIL‐88NH2 selected Cys featuring great sensitivity in the water, with a detection limit of 5.33 μM. A CCK8 experiment found that Fe‐MIL‐88NH2 had low cytotoxicity. Additionally, the constructed fluorescent platform was used as one signaling tool in monitoring Cys for detecting exo/endogenous Cys in A549 cells. [ABSTRACT FROM AUTHOR]

This article presents information on forthcoming papers to be published in coming issues of the periodical "European Journal of Biochemistry." Some of the papers are: "Localization of Histone HS in the Subunit Organization of Chromatin Using ImmunoeIectron Microscopy"; "Presence of an Amino Acid Oxidase in Photosystem II of Anacystis nidutans"; "Aldoximes: Active-Site Probes of Alcohol Dehydrogenases"; and "Quinone Reductases of Higher Plants."

This paper reports the hyper‐Raman (HR) spectra of the 20 amino acids in aqueous solution in the range of 400–1,800 cm−1 with an excitation wavelength of 532 nm. A remarkable common feature in the nonresonance HR spectra is the large intensity of the HR bands of the COO− group. Whereas the peak position is mostly identical between the HR and Raman spectra, the intensity pattern is not. We discuss the similarities and dissimilarities between the pattern of the two spectra of each amino acid and give possible assignments to each HR band by comparing them with those of the corresponding Raman band. This study offers a reference for the HR spectra of the amino acids as the basic building block of proteins. It helps interpret the HR spectra of proteins and peptides. [ABSTRACT FROM AUTHOR]

The alteration of amino acid register in peptides could affect their folding properties and thus functions. The effect of sequence in metal ion induced folding of peptide/protein is important in the design of new functional protein structures, such as biomimetics. In this paper, a set of hairpin peptides with identical composition but different histidine locations have been designed to exploit the metal ion‐mediated peptide intramolecular folding transformation through the adjustment of histidine and lysine residue locations. The results demonstrated that the histidine positions in peptide sequence could dramatically affect the coordination modes between peptides and Cu(II) ion. The Cu(II) coordination could affect the secondary structure transformation and self‐assembly along with electrostatic interaction and hydrogen bonding synergistically. Three molecules with VHVH sequence at each side of the turn segment (VDPPT) were apt to coordinate with Cu(II) ion with three or four histidines. The closer the VHVH motifs were to the turn segment, the more easier the molecules were to form β sheet structure with the promotion of Cu(II) ions. These results demonstrated that the purposeful location of key amino acids in peptides could achieve the controllable conformation transformation of hairpin peptides, which provides useful strategies for biomimetic design, such as metalloenzymes. [ABSTRACT FROM AUTHOR]

Deep understanding of structure–property relationship between packing of chiral building units and their chiroptical behaviors would significantly facilitate the rational design and fabrication of the emerging chiroptical materials such as circularly polarized luminescence (CPL) emissive materials. In this paper, we unveil the universal existence of supramolecular tilt helical superstructures in self‐assembled π‐conjugated amino acid derivatives. A series of coded amino acid methyl esters were conjugated to anthracene segments at N‐terminus, which afforded 21 and 31 symmetry supramolecular tilt chirality in solid‐states. Helical assemblies enabled diversified Cotton effects and CPL performances, which were in accordance with the tilted chirality between anthracene segments. Such correlation shows fine universality, whereby the chiroptical prediction could be realized. Furthermore, on top of charge‐transfer complexation, manipulation of CPL emission colors and handedness were realized. [ABSTRACT FROM AUTHOR]

Deep understanding of structure–property relationship between packing of chiral building units and their chiroptical behaviors would significantly facilitate the rational design and fabrication of the emerging chiroptical materials such as circularly polarized luminescence (CPL) emissive materials. In this paper, we unveil the universal existence of supramolecular tilt helical superstructures in self‐assembled π‐conjugated amino acid derivatives. A series of coded amino acid methyl esters were conjugated to anthracene segments at N‐terminus, which afforded 21 and 31 symmetry supramolecular tilt chirality in solid‐states. Helical assemblies enabled diversified Cotton effects and CPL performances, which were in accordance with the tilted chirality between anthracene segments. Such correlation shows fine universality, whereby the chiroptical prediction could be realized. Furthermore, on top of charge‐transfer complexation, manipulation of CPL emission colors and handedness were realized. [ABSTRACT FROM AUTHOR]

In interfaces between inorganic and biological materials relevant for technological applications, the general challenge of structure determination is exacerbated by the high flexibility of bioorganic components, chemical bonding, and charge rearrangement at the interface. In this paper, we investigate a chemically complex building block, namely, the arginine (Arg) amino acid interfaced with Cu, Ag, and Au (111) surfaces. We investigate how the environment changes the accessible conformational space of this amino acid by building and analyzing a database of thousands of structures optimized with the Perdew‐Burke‐Ernzerhof (PBE) functional, including screened pairwise van der Waals interactions. When in contact with metallic surfaces, the accessible space for Arg is dramatically reduced, while the one for Arg‐H+ is instead increased if compared to the gas phase. This is explained by the formation of strong bonds between Arg and the surfaces and by their absence and charge screening on Arg‐H+ upon adsorption. We also observe protonation‐dependent stereoselective binding of the amino acid to the metal surfaces: Arg adsorbs with its chiral CαH center pointing H away from the surfaces, while Arg‐H+ adsorbs with H pointing toward the surface. [ABSTRACT FROM AUTHOR]

The article presents the forthcoming papers that will be published in the "European Journal of Biochemistry." Some of these articles to be published are "Purification and Characterization of Thermus Caldophilus GK24 DNA Polymerase," by J.H. Park, J.S. Kim, S.-T. Kwon and D.-S. Lee, "Lactotransferrin Binding to Its Platelet Receptor Inhibits Platelet Aggregation," by B. Leveugle, J. Mazurier, D. Legrand, C. Mazurier, J. Montreuil and G. Spik and "Does Escherichia Coli Possess a Second Critrate Synthase Gene?," by A.J. Patton, D.W. Hough, P. Towner and M.J. Danson.

The article presents information on several research papers related to biochemistry that would be published in coming issues of the European Journal of Biochemistry. Some of the research topics include: differentiation of ovine brown adipocyte precursor cells in a chemically defined serum-free medium; production and purification of recombinant human interleukin-6 secreted by the yeast Saccharomyces cerevisiae; binding of sugar phosphates, inositol phosphates and phosphorylated amino acids to actin; etc.

The article presents information on the forthcoming papers and articles that will be published by the "European Journal of Biochemistry." Some of them are Ionic-strength-dependent substrate inhibition of the lysis of Micrococcus luteus by hen egg-white lysozyme by I. M.A. Verhamme, G. W. K. van Dedem and A. R. Lauwers, A maximum of two tryptophan residues in gene-32 protein from phage T4 undergo stacking interactions with single-stranded polynucleotides, Cell-cycle-related metabolic and enzymatic events in proliferating rat thymocytes.

Rationale: Organic nitrogen (N) greatly exceeds inorganic N in soils, but the complexity and heterogeneity of this important soil N pool make investigations into the fate of N‐containing additions and soil organic N cycling challenging. This paper details a novel approach to investigate the fate of applied N in soils, generating quantitative measures of microbial assimilation and of newly synthesized soil protein. Methods: Laboratory incubation experiments applying 15N‐ammonium, 15N‐nitrate and 15N‐glutamate were carried out and the high sensitivity and selectivity of gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS) exploited for compound‐specific 15N stable isotope probing (15N‐SIP) of extracted incubation soil amino acids (AAs; as N‐acetyl, O‐isopropyl derivatives). We then describe the interpretation of these data to obtain a measure of the assimilation of the applied 15N‐labelled substrate by the soil microbial biomass and an estimate of newly synthesised soil protein. Results: The cycling of agriculturally relevant N additions is undetectable via bulk soil N content and δ15N values and AA concentrations. The assimilation pathways of the three substrates were revealed via patterns in AA δ15N values with time, reflecting known biosynthetic pathways (e.g. ammonium uptake occurs first via glutamate) and these data were used to expose differences in the rates and fluxes of the applied N substrates into the soil protein pool (glutamate > ammonium > nitrate). Conclusions: Our compound‐specific 15N‐SIP approach using GC/C/IRMS offers a number of insights, inaccessible via existing techniques, into the fate of applied 15N in soils and is potentially widely applicable to the study of N cycling in any soil, or indeed, in any complex ecosystem. © 2016 The Authors. Rapid Communications in Mass Spectrometry Published by John Wiley & Sons Ltd. [ABSTRACT FROM AUTHOR]

The use of functional amino acids during pregnancy has been linked to improved reproduction in mammals. In this context, arginine is a precursor in the synthesis of numerous molecules, such as nitric oxide and polyamines, which play an important role during reproduction. However, contradictory studies are found in the literature, particularly regarding the amount of supplementation and the period of pregnancy in which it is used. The objective of this study was to evaluate the effects of dietary arginine supplementation for pregnant sows on foetal development via a systematic review. The search for papers was performed during the month of December 2015, in the databases ISI Web of Science, Science Direct, Scopus, and Sci ELO. From a total of 5675 returned studies, only 13 papers were selected after applying selection criteria. Most (47%) of the studies that evaluated the effects of dietary arginine supplementation on foetal development in pigs used 1% arginine. Supplementation was initiated in the first third of pregnancy in 47% of tests, including in both primiparous and multiparous sows. These studies showed positive results for embryo survival and foetal development, evidenced by the increase in placental weight and the number and weight of piglets born alive. Of all evaluated studies, 53% showed benefits on foetal development. It is concluded that supplementing dietary arginine in gestating sows can benefit embryo survival and foetal development. However, to establish a supplementation plan with this amino acid, aspects related to the period of pregnancy, supplementation levels, and source of arginine must be well defined. [ABSTRACT FROM AUTHOR]

This paper reports the effects of four popular cooking methods viz. grilling, boiling, frying, and microwaving on the proximate and nutritional compositions of freshwater mud eel (FWME) muscle. The moisture content of raw FWME muscle was 74.45%, which was similar in boiled products but lower in grilled, fried, and microwaved products (p ≤.05). The protein content in raw and cooked FWME muscles varied between 14.49% and 21.28%. There were found 20 different fatty acids in FWME muscle of which palmitic acid was the most abundant one with an amount of 26.51%–29.70% in raw and cooked FWME muscles. FWME muscle contained a substantial amount of ω‐3 polyunsaturated fatty acids, ranging from 7.54% to 13.7%. However, the thermal effects during cooking decreased the ω‐3 polyunsaturated fatty acid contents. There were seven essential and eight nonessential amino acids available in FWME muscle; among the essential amino acids, lysine content was the highest. Raw and cooked FWME were very rich in calcium, between 794.52 mg/100 g and 883.24 mg/100 g muscle. Among the studied heavy metals, Pb content was the highest. However, all the heavy metal contents were within acceptable limits determined by health risk assessment, that is, target hazard quotient and target cancer risk. [ABSTRACT FROM AUTHOR]

Presents articles for publication in future issues of the "European Journal of Biochemistry". Chemical structure of the lipopolysaccharide of Haemophilus influenzae strain; Progression of mammalian DNA replication intermediates to mature chromatin; Purification, characterization and induction of phenylalanine ammonia lyase in Phaseolus vulgaris.

Hybrid perovskites demonstrate high potential in optoelectronic applications. Their main drawback is their low stability under humid conditions. In this paper, one of nature's strategies is implemented—the incorporation of amino acids into the crystal lattice—in order to improve the stability of methylammonium lead bromide (MAPbBr3) in water, and to tune its structure, as well as its optical and thermal properties. The amino acid lysine, which possesses two NH3+ groups, is incorporated into the hybrid unit cell, by substituting two methylammonium ions and serves as a "molecular bridge". This incorporation induces a decrease in the lattice parameter of the host, accompanied with an increase in its bandgap and noticeable changes in its morphology. Furthermore, a substantial decrease in the thermal expansion coefficient of MAPbBr3 and a shift of its cubic‐to‐tetragonal phase transformation temperature are observed. Two different modes of incorporation are identified, which depend on the conditions of crystallization. These modes dictate the level of lysine incorporation and the magnitude of MAPbBr3 bandgap changes. Notably, lysine incorporation strongly increases the perovskite stability in water. This study demonstrates a unique and promising approach to tune the properties and improve the stability of hybrid perovskites via this novel bioinspired route. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the physical basis behind the molecular biochirality from the computation of a parity violation energy difference (PVED) in enantiomers of organic molecules (e.g., amino acids, which occur as levogyrous‐type in nature), by considering the influence of fundamental interactions beyond the standard model of elementary particles and interactions. Particularly, we study the role of a 4‐D Chern‑Simons theory at the origin of this PVED, the Carroll‑Field‑Jackiw electrodynamics, which violates both Lorentz and parity symmetries. Then, we consider terrestrial and Jovian scenarios where the influence of a modified (effective) magnetic field generated by the planets on the molecules is taken into account in the calculation of PVED. Besides this quantity, we also calculate the relative quantity excess of an enantiomer over the other in a thermal bath. Finally, we compare the obtained results with those ones from other models based on fundamental interactions. [ABSTRACT FROM AUTHOR]

The effects of processing on the content of amino acids and fatty acids and the release of glucose from quinoa grains were evaluated in this paper. The processes included dehulling, boiling, extrusion, heating under pressure, and baking (infrared heating). The retention rate (AR) of essential amino acids and fatty acids of dehulled and boiled quinoa was 100%. The oil content of the extruded quinoa samples of two varieties was 47.71% and 39.75% lower than the corresponding raw quinoa samples. Baking and heating under pressure had different effects on the essential amino acid content, fatty acid content, and hydrolysis rate of quinoa starch. The results indicated the different cooking methods affect the essential amino acid content, fatty acid composition, release of glucose, and nutritional quality of quinoa, and moderate processing should be adopted to fully utilize the essential amino acids, fatty acids, and starch in quinoa. [ABSTRACT FROM AUTHOR]

L‐2‐[18F]fluoro‐alpha‐methylphenylalanine (2‐[18F]FAMP) is a promising amino acid tracer for positron emission tomography (PET) imaging, yet the low production yield of direct electrophilic radiofluorination with [18F]F2 necessitates further optimization of the radiolabeling process. This paper describes a two‐step preparation method for L‐2‐[18F]fluoro‐alpha‐methylphenylalanine (2‐[18F]FAMP) starting from [18F]fluoride. The (Mesityl)(L‐alpha‐methylphenylalanine)‐2‐iodonium tetrafluoroborate precursors with various protecting groups were prepared. The copper‐mediated 18F‐fluorination of the iodonium salt precursors successfully produced 2‐[18F]FAMP. The highest radio chemical conversion of 57.6% was noted with N‐Piv‐protected (mesityl)(aryl)iodonium salt in the presence of 5 equivalent of Cu (OTf)2. Subsequent deprotection with 57% hydrogen iodide produced 2‐[18F]FAMP within 120 min in 21.4 ± 11.7% overall radiochemical yield with >95% radiochemical purity and an enantiomeric excess >99%. The obtained 2‐[18F]FAMP showed comparable biodistribution profiles in normal mice with that of the carrier‐added 2‐[18F]FAMP. These results indicate that usefulness of copper mediated 18F‐fluorination for the production of 2‐[18F]FAMP, which would facilitate clinical translation of the promising tumor specific amino acid tracer. Individual facilities could adopt either production method based on radioactivity demand and equipment availability. [ABSTRACT FROM AUTHOR]

Biallelic mutations in ECHS1, encoding the mitochondrial enoyl‐CoA hydratase, have been associated with mitochondrial encephalopathies with basal ganglia involvement. Here, we describe a novel clinical presentation consisting of dystonia‐ataxia syndrome with hearing loss and a peculiar torsional nystagmus observed in two adult siblings. The presence of a 0.9‐ppm peak at MR spectroscopy analysis suggested the accumulation of branched‐chain amino acids. Exome sequencing in index probands identified two ECHS1 mutations, one of which was novel (p.V82L). ECHS1 protein levels and residual activities were reduced in patients' fibroblasts. This paper expands the phenotypic spectrum observed in patients with impaired valine catabolism. [ABSTRACT FROM AUTHOR]

Tryptophan is a key amino acid related to metabolomics in gastric cancer. To date, methods were developed only for the assay of l‐tryptophan, the role of d‐tryptophan being not yet established. Therefore, four stochastic sensors based on different graphene materials modified with β‐cyclodextrins, 2,2‐diphenyl‐1‐picrylhydrazyl, and protoporphyrin IX were designed and used for enantioanalysis of tryptophan in whole blood samples. High sensitivities, and reliabilities were recorded when the stochastic sensors were used for the enantioanalysis of tryptophan in whole blood samples. The paper opened a new chapter in early detection of gastric cancer, based on establishing the role of d‐tryptophan in metabolomics, and in early diagnosis of gastric cancer. [ABSTRACT FROM AUTHOR]