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Vibrational spectroscopy of protein structure often utilizes 13C18O-labeling of backbone carbonyls to further increase structural resolution. However, sidechains such as arginine, aspartate, and glutamate absorb within the same spectral region, complicating the analysis of isotope-labeled peaks. In this study, we report that the waiting time between pump and probe pulses in two-dimensional infrared spectroscopy can be used to suppress sidechain modes in favor of backbone amide I′ modes based on differences in vibrational lifetimes. Furthermore, differences in the lifetimes of 13C18O-amide I′ modes can aid in the assignment of secondary structure for labeled residues. Using model disordered and β-sheet peptides, it was determined that while β-sheets exhibit a longer lifetime than disordered structures, amide I′ modes in both secondary structures exhibit longer lifetimes than sidechain modes. Overall, this work demonstrates that collecting 2D IR data at delayed waiting times, based on differences in vibrational lifetime between modes, can be used to effectively suppress interfering sidechain modes and further identify secondary structures. [ABSTRACT FROM AUTHOR]

Hybrid quantum mechanics/molecular mechanics (QM/MM) simulations have become an essential tool in computational chemistry, particularly for analyzing complex biological and condensed phase systems. Building on this foundation, our work presents a novel implementation of the Gaussian Electrostatic Model (GEM), a polarizable density-based force field, within the QM/MM framework. This advancement provides seamless integration, enabling efficient and optimized QM/GEM calculations in a single step using the LICHEM Code. We have successfully applied our implementation to water dimers and hexamers, demonstrating the ability to handle water systems with varying numbers of water molecules. Moreover, we have extended the application to describe the double proton transfer of the aspartic acid dimer in a box of water, which highlights the method's proficiency in investigating heterogeneous systems. Our implementation offers the flexibility to perform on-the-fly density fitting or to utilize pre-fitted coefficients to estimate exchange and Coulomb contributions. This flexibility enhances efficiency and accuracy in modeling molecular interactions, especially in systems where polarization effects are significant. [ABSTRACT FROM AUTHOR]

K-Ras is the most commonly mutated oncogene in human cancer. The recently approved non-small cell lung cancer drugs sotorasib and adagrasib covalently capture an acquired cysteine in K-Ras-G12C mutation and lock it in a signaling-incompetent state. However, covalent inhibition of G12D, the most frequent K-Ras mutation particularly prevalent in pancreatic ductal adenocarcinoma, has remained elusive due to the lack of aspartate-targeting chemistry. Here we present a set of malolactone-based electrophiles that exploit ring strain to crosslink K-Ras-G12D at the mutant aspartate to form stable covalent complexes. Structural insights from X-ray crystallography and exploitation of the stereoelectronic requirements for attack of the electrophile allowed development of a substituted malolactone that resisted attack by aqueous buffer but rapidly crosslinked with the aspartate-12 of K-Ras in both GDP and GTP state. The GTP-state targeting allowed effective suppression of downstream signaling, and selective inhibition of K-Ras-G12D-driven cancer cell proliferation in vitro and xenograft growth in mice.

1H spin-lattice relaxation studies have been performed for binary systems, including glycerol as the first component and alanine, glycine, and aspartic acid (with different levels of deuteration) as the second one. The relaxation studies have been performed in the frequency range from 10 kHz to 10 MHz vs temperature. A theoretical framework, including all relevant 1H–1H and 1H–2H relaxation pathways, has been formulated. The theory has been exploited for a thorough interpretation of a large set of the experimental data. The importance of the 1H–2H relaxation contributions has been discussed, and the possibility of revealing dynamical properties of individual liquid components in binary liquids has been carefully investigated. As far as the dynamical properties of the specific binary liquids, chosen as an example, are considered, it has been shown that in the presence of the second component (alanine, glycine, and aspartic acid), both molecular fractions undergo dynamics similar to that of glycerol in bulk. [ABSTRACT FROM AUTHOR]

Canavan disease is a leukodystrophy caused by ASPA mutations that diminish oligodendroglial aspartoacylase activity, and is characterized by markedly elevated brain concentrations of the aspartoacylase substrate N-acetyl-l-aspartate (NAA) and by astroglial and intramyelinic vacuolation. Astroglia express NaDC3 (encoded by SLC13A3), a sodium-coupled transporter for NAA and other dicarboxylates. Astroglial conditional Slc13a3 deletion in aspartoacylase-deficient Canavan disease model mice ("CD mice") reversed brain NAA elevation and improved motor function. These results demonstrate that astroglial NaDC3 contributes to brain NAA elevation in CD mice, and suggest that suppressing astroglial NaDC3 activity would ameliorate human Canavan disease.

Chemotactic bacteria not only navigate chemical gradients, but also shape their environments by consuming and secreting attractants. Investigating how these processes influence the dynamics of bacterial populations has been challenging because of a lack of experimental methods for measuring spatial profiles of chemoattractants in real time. Here, we use a fluorescent sensor for aspartate to directly measure bacterially generated chemoattractant gradients during collective migration. Our measurements show that the standard Patlak-Keller-Segel model for collective chemotactic bacterial migration breaks down at high cell densities. To address this, we propose modifications to the model that consider the impact of cell density on bacterial chemotaxis and attractant consumption. With these changes, the model explains our experimental data across all cell densities, offering insight into chemotactic dynamics. Our findings highlight the significance of considering cell density effects on bacterial behavior, and the potential for fluorescent metabolite sensors to shed light on the complex emergent dynamics of bacterial communities.

Background: Recurrent pregnancy loss (RPL) affects women's reproductive health seriously, with immune dysfunction playing a key role in its cause, yet the exact mechanisms remain elusive. We aim to investigate potential mechanisms and identify biomarkers linked to RPL. Methods: Immune cytokine testing and metabolomic profiling were conducted on the serum of 34 RPL patients and 30 healthy individuals. The metabolic pathways of the differential metabolites were analyzed, and specific metabolites were validated through targeted profiling. Potential biomarkers were identified, and the relationships between immune cytokines and differential metabolites were explored. Results: In the RPL group, serum interleukin-6 and interleukin-10 levels were significantly higher, while interleukin-2 and interferon-g were significantly lower. A total of 296 differential metabolites were detected by untargeted metabolomic profiling between the RPL and control groups, with most linked to amino acid metabolism. Targeted metabolomic profiling of amino acid metabolism revealed upregulation of indole-3-acetic acid, tyrosine, glycine, isoleucine, tryptophan, lysine, aspartic acid, arginine, leucine, threonine, glutamic acid, cystine, and phenylpyruvic acid (PPA) in the RPL group. Moreover, PPA and 5-hydroxy-Ltryptophan showed great potential in predicting RPL in a diagnostic model. Cystine and tyrosine were associated with immune cytokines in correlation analysis. Conclusion: The study highlights the role of amino acid metabolism in RPL pathogenesis, suggesting that PPA and 5-HTP may be potential predictive indicators, while cystine and tyrosine may potentially regulate immune responses related to RPL. Further investigation into the molecular mechanisms underlying these findings could potentially result in the creation of novel diagnostic and therapeutic approaches for RPL. [ABSTRACT FROM AUTHOR]

Myocardial infarction is a major cause of morbidity and mortality worldwide. Metabolomic investigations may be useful for understanding the pathogenesis of ST-segment elevation myocardial infarction (STEMI). STEMI patients were comprehensively examined via targeted metabolomic profiling, machine learning and weighted correlation network analysis. A total of 195 subjects, including 68 STEMI patients, 84 patients with stable angina pectoris (SAP) and 43 non-CVD patients, were enrolled in the study. Metabolomic profiling involving the quantitative analysis of 87 endogenous metabolites in plasma was conducted. This study is the first to perform targeted metabolomic profiling in patients with STEMI. We identified 36 significantly altered metabolites in STEMI patients. Increased levels of four amino acids, eight acylcarnitines, six metabolites of the NO–urea cycle and neurotransmitters, and three intermediates of tryptophan metabolism were detected. The following metabolites exhibited decreased levels: six amino acids, three acylcarnitines, three components of the NO–urea cycle and neurotransmitters, and three intermediates of tryptophan metabolism. We found that the significant changes in tryptophan metabolism observed in STEMI patients—the increase in anthranilic acid and tryptophol and decrease in xanthurenic acid and 3-OH-kynurenine—may play important roles in STEMI pathogenesis. On the basis of the differences in the constructed weighted correlation networks, new significant metabolite ratios were identified. Among the 22 significantly altered metabolite ratios identified, 13 were between STEMI patients and non-CVD patients, and 17 were between STEMI patients and SAP patients. Seven of these ratios were common to both comparisons (STEMI patients vs. non-CVD patients and STEMI patients vs. SAP patients). Additionally, two ratios were consistently observed among the STEMI, SAP and non-CVD groups (anthranilic acid: aspartic acid and GSG (glutamine: serine + glycine)). These findings provide new insight into the diagnosis and pathogenesis of STEMI. [ABSTRACT FROM AUTHOR]

Summary Class 2 Type V‐A CRISPR‐Cas (Cas12a) nucleases are powerful genome editing tools, particularly effective in A/T‐rich genomic regions, complementing the widely used CRISPR‐Cas9 in plants. To enhance the utility of Cas12a, we investigate three Cas12a orthologs—Mb3Cas12a, PrCas12a, and HkCas12a—in plants. Protospacer adjacent motif (PAM) requirements, editing efficiencies, and editing profiles are compared in rice. Among these orthologs, Mb3Cas12a exhibits high editing efficiency at target sites with a simpler, relaxed TTV PAM which is less restrictive than the canonical TTTV PAM of LbCas12a and AsCas12a. To optimize Mb3Cas12a, we develop an efficient single transcription unit (STU) system by refining the linker between Mb3Cas12a and CRISPR RNA (crRNA), nuclear localization signal (NLS), and direct repeat (DR). This optimized system enables precise genome editing in rice, particularly for fine‐tuning target gene expression by editing promoter regions. Further, we introduced Arginine (R) substitutions at Aspartic acid (D) 172, Asparagine (N) 573, and Lysine (K) 579 of Mb3Cas12a, creating two temperature‐tolerant variants: Mb3Cas12a‐R (D172R) and Mb3Cas12a‐RRR (D172R/N573R/K579R). These variants demonstrate significantly improved editing efficiency at lower temperatures (22 °C and 28 °C) in rice cells, with Mb3Cas12a‐RRR showing the best performance. We extend this approach by developing efficient Mb3Cas12a‐RRR STU systems in maize and tomato, achieving biallelic mutants targeting single or multiple genes in T0 lines cultivated at 28 °C and 25 °C, respectively. This study significantly expands Cas12a's targeting capabilities in plant genome editing, providing valuable tools for future research and practical applications. [ABSTRACT FROM AUTHOR]

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Background: Advances in in vivo MRI techniques enable cerebral barrier transfer rates (Ktrans) measurement in patients with vascular cognitive impairment and dementia (VCID). However, a consensus has not been reached on the dynamic contribution and importance of cerebral barrier abnormalities to the differential diagnosis of dementia subtypes. Our goal was to investigate the dynamics of blood-brain barrier (BBB) and blood-CSF barrier (BCSFB) Ktrans in patients with VCID longitudinally and determine the effect of aging. Methods: We studied subjects at two time points over two years; they were 65.5 years of age (SD = 15.94, M/F = 24/14) at the first visit. We studied 38 patients, 18 of whom had two visits. We calculated the BBB and BCSFB Ktrans with dynamic contrast-enhanced T1 MR, and we used 1H-MR spectroscopy to measure N-acetylaspartate (NAA) levels in the white matter as a marker of injury. In addition, we measured CSF levels of active-matrix metalloproteinase-3 (MMP3) as an inflammatory biomarker to aid in patient clustering. Results: Longitudinal BBB measurements revealed variable dynamic behavior: after two years, the BBB Ktrans increased in 55% of patients and decreased in the remaining 45% unpredictably. We did not find a significant linear model of BBB Ktrans versus age for VCID. For healthy controls, the model was Ktrans = 0.0014 + 0.0002 age, which was significant (p = 0.046). VCID patients showed a reduction in BCSFB Ktrans compared to healthy controls (p = 0.01). Combining NAA, CSF MMP3, and Ktrans in a clustering analysis separated patients into groups. Conclusion: These results suggest that BBB Ktrans in VCID is dynamic and BCSFB Ktrans reduced by age. By combining inflammatory biomarkers with BBB Ktrans data, it is possible to separate VCID patients into distinct groups with different underlying pathologies. [ABSTRACT FROM AUTHOR]

In order to alleviate the influence of greenhouse effect on global climate change, the effective utilization of CO2 to prepare fine chemicals should be paid more attention to, however, which is greatly blocked by the catalyst with low efficiency. Here, alkali metal (Li, Na, or K) are employed as a modification aid to prepare CuO/ZrO2 catalyst for CO2 hydrogenation to methanol. The effects of alkali metal on physicochemical properties and catalytic activities of CuO/ZrO2 catalyst were studied in detail by the XRD, N2‐physisorption, ICP‐OES, SEM/EDS, H2/N2O/CO2/NH3‐chemisorption, and evaluation test. The results verified that the use of complex combustion method enabled the uniform combination of all components in precursor. High‐temperature calcination (700 °C) further enhanced the strong interaction and synergistic effect between Cu and ZrO2. Most importantly, the introduction of alkali metal effectively altered the structure and catalytic activity of CuO/ZrO2 catalysts. However, the selectivity to methanol increased while the CO2 conversion decreased regardless of different kinds of alkali metal being introduced to the CuO/ZrO2 catalysts. For example, CuO/ZrO2 catalyst modified by K exhibited excellent performance for methanol production that 98.9% selectivity of methanol based on 8.8% conversion of CO2 after 48 h online reaction. [ABSTRACT FROM AUTHOR]

Objective: To explore the effect and anxiolytic mechanism of a natural remedy called Fructus gardeniae (FG). Methods: The elevated-plus maze (EPM) test was used to confirm the anxiolytic effect of FG. The potential and anxiolytic components, targets, and route processes of FG were investigated using the network pharmacology method in conjunction with metabolomics and molecular docking technologies. Results: FG could greatly enhance the proportion of time and times of opening arms, according to the EPM data. As to the metabolomics findings, a total of 61 distinct metabolites were found, mainly involved in glycine, serine, and threonine metabolism as well as alanine, aspartate, and glutamate metabolism. The primary active ingredients of FG, nicotiflorin, jasminodiol, and crocetin, demonstrated substantial binding affinities with monoamine oxidase A (MAOA), monoamine oxidase A (ACHE), malate dehydrogenase 2 (MDH2), glutamate decarboxylase 2 (GAD2), glutamate decarboxylase 1 (GAD1), and nitric oxide synthase (NOS1), according to the findings of network pharmacology and molecular docking. Conclusion: FG exerts an anxiolytic action via targeting MAOA, ACHE, MDH2, GAD2, GAD1, and NOS1, and regulating the metabolism of glycine, serine, and threonine as well as alanine, aspartic acid, and glutamic acid. [ABSTRACT FROM AUTHOR]

Ichthyoses comprise a large heterogeneous group of skin disorders, characterized by generalized scaly and hyperkeratotic skin. We investigated a miniature poodle with early onset generalized scaling, dry and irregularly thickened skin, paw pad hyperkeratosis and abnormalities in hair and teeth. The clinical signs of ichthyosis were confirmed by histopathological examination, which revealed mild epidermal hyperplasia and lamellar orthokeratotic hyperkeratosis. A hereditary condition was suspected and a genetic investigation was initiated. We sequenced the whole genome of the affected dog and searched for potentially causative variants in functional candidate genes for the observed phenotype. The analysis revealed a heterozygous in‐frame deletion in DSP, NC_049256.1:g.8804542_8804544del resulting from a de novo mutation event as evidenced by genotyping leukocyte DNA from both parents. The 3 bp deletion is predicted to remove one aspartic acid without disrupting the open reading frame (XM_038584124.1:c.1821_1823del, XP_038440052.1:p.(Asp608del)). The DSP gene encodes desmoplakin, a desmosomal plaque protein, responsible for cell–cell adhesion to provide resistance to mechanical stress in epidermal and cardiac tissues. We hypothesize that the deletion of one amino acid in the N‐terminal globular head domain acts in a dominant negative manner and thus impairs the proper connection with other proteins. Several variants in DSP in humans and cattle have been described to result in different phenotypes associated with hair and skin abnormalities, sometimes in combination with variable cardiac and/or dental manifestations. In conclusion, we characterized a new syndromic ichthyosis phenotype in a dog and identified a de novo 3 bp deletion in the DSP gene as causal variant. [ABSTRACT FROM AUTHOR]

Liver fibrosis plays an important role in the progression of liver disease, but there is a severe shortage of direct and efficacious pharmaceutical clinical interventions. Literature research indicates that aspartic acid exhibits hepatoprotective properties. In this paper, 32 target compounds were designed and synthesized utilizing aspartic acid as the lead compound, of which 22 were new compounds not reported in the literature. These compounds were screened for their inhibitory effects on the COL1A1 promoter to assess in vitro anti-liver fibrosis activity and summarized structure–activity relationships. Four compounds exhibited superior potency with inhibition rates ranging from 66.72% to 97.44%, substantially higher than EGCG (36.46 ± 4.64%) and L-Asp (11.33 ± 0.35%). In an LPS-induced inflammation model of LX-2 cells, both 41 and 8a could inhibit the activation of LX-2 cells, reducing the expression of COL1A1, fibronectin, and α-SMA. Upon further investigation, 41 and 8a ameliorated liver fibrosis by inhibiting the IKKβ-NF-κB signaling pathway to alleviate inflammatory response. Overall, the study evaluated the anti-liver fibrosis effects of aspartic acid derivatives, identified the potency of 41, and conducted a preliminary exploration of mechanisms, laying the foundation for the discovery of novel anti-liver fibrosis agents. [ABSTRACT FROM AUTHOR]

BACKGROUND: The main edible part of the Lou onion is the pseudostem, which is highly valued for its distinctive flavour. However, harvesting decisions for the pseudostem are often based on size and market price, with little consideration given to flavour. By clarifying the growth of flavour in pseudostems, farmers and consumers may benefit from evidence‐based insights that help optimize harvesting time and maximize flavour quality. RESULTS: This study employed amino acid analysis and gas chromatography–ion migration spectroscopy (GC–IMS) to elucidate the compounds of the pseudostem across different growth phases, and 17 amino acids and 61 volatile substances. Subsequently, analysis revealed that 18 compounds, including arginine (Arg), aspartic acid (Asp), glutamic acid (Glu), valine (Val), (E)‐2‐nonenal, decanal, 2,4‐nonadienal, 2‐octenal, (Z)‐4‐decenal, 2,4‐decadienal benzeneacetaldehyde, linalool, eugenol, (Z)‐6‐nonen‐1‐ol, methyl anthranilate, 2‐acetylpyridine, 3‐sec‐butyl‐2‐methoxypyrazine, and 2,6‐dichlorophenol, were the key compounds in determining the flavour characteristics of the pseudostems, as assessed by taste activity value and relative odour activity value calculations. In addition, correlation analysis, focusing on five amino acids and 38 volatile compounds with variable importance for predictive components scores of >1, identified anisaldehyde, eugenol, (Z)‐6‐nonen‐1‐ol, 2,4‐decadienal, 3‐sec‐butyl‐2‐methoxypyrazine, Arg, Asp, and Val as the key differentiators and contributors to the pseudostems flavour profile. CONCLUSION: During the rapid growth of Lou onions just before the emergence of flower stems, the pseudostem exhibited the most prominent flavour, making this stage most suitable for harvesting compared to the regreening growth stage and the rapid growth period of the aerial bulbs. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Introduction: Canavan disease (CD) is a rare autosomal recessive neurodegenerative disorder caused by a deficiency of aspartoacylase A, an enzyme that degrades N-acetylaspartate (NAA). The disease is characterized by progressive white matter degeneration, leading to intellectual disability, seizures, and death. This retrospective study aims to describe the full spectrum of magnetic resonance imaging (MRI) findings in a large case series of CD patients. Materials and methods: MRI findings in 18 patients with confirmed CD were investigated, and the full spectrum of brain abnormalities was compared with the existing literature to provide new insights regarding the brain MRI findings in these patients. All the cases were proven based on genetic study or NAA evaluation in urine or brain. Results: Imaging analysis showed involvement of the deep and subcortical white matter as well as the globus pallidus in all cases, with sparing of the putamen, caudate, and claustrum. The study provides updates on the imaging characteristics of CD and validates some underreported findings such as the involvement of the lateral thalamus with sparing of the pulvinar, involvement of the internal capsules and corpus callosum, and cystic formation during disease progression. Conclusion: To our knowledge, this is one of the largest case series of patients with CD which includes a detailed description of the brain MRI findings. The study confirmed many of the previously reported MRI findings but also identified abnormalities that were previously rarely or not described. We speculate that areas of ongoing myelination are particularly vulnerable to changes in CD. [ABSTRACT FROM AUTHOR]

The emergency of peptide-assembled nanomaterials motivates the efforts towards understanding the composition effects governing the assembly structure of peptides. Herein, we used time-lapse atomic force microscopy (AFM) to characterize the time-dependent structural transformation of phenylalanine (F)-rich self-assembled peptides and elucidated the impacts of composition heterogeneity on modulating peptide aggregation. Four binary peptides (F5Y5, F5A5, F5H5, and F5D5) were synthesized to arrange distinct types of amino acids, including aromatic tyrosine (Y), nonpolar alanine (A), cationic histidine (H), and anionic aspartic acid (D), in the proximity of an F-rich moiety. We compared the time-dependent structural transitions of these peptide assemblies using AFM. F5Y5 and F5A5 were observed to form fibril-like aggregates over time, whereas F5H5 and F5D5 assembled into globular particles during the time course examined. The impacts of neighboring amino acids on affecting F-rich peptide fibrillation are in line with the hydrophobicity scales of amino acid side chains. Specifically, Y and A facilitate the fibril aggregation, whereas H and D hinder the fibril formation of F-rich peptides. Our results manifest the hydrophobicity of amino acids proximal to the F residues is important for the fibril-like aggregation of peptides. [ABSTRACT FROM AUTHOR]

The caseinolytic protease (ClpP)-producing strain CHFM, isolated from Algerian goat milk, was identified as Lactiplantibacillus pentosus through 16 S rRNA sequence analysis. The optimal conditions for ClpP expression by Lpb. pentosus CHFM were determined in a modified MRS medium, where peptone was replaced with casein. The most favourable conditions were a pH of 8.0, a temperature between 25°C and 55°C, and an incubation period of 48 h. PCR screening and subsequent cloning and sequencing of the ClpP-encoding gene from the Lpb. pentosus CHFM genome revealed two conservative substitutions: threonine to serine at position 161, and aspartic acid to glutamic acid at position 182. Bioinformatic analysis indicated an instability index value of 40.51 for ClpP CHFM, suggesting stability, with an alpha-helix being the predominant secondary structure element, followed by a random coil. The aliphatic index was 97.60, indicating thermal stability. The GRAVY index was −0.23, suggesting enhanced interaction with water. The molecular weight was found to be 25.5 kDa with an isoelectric point (pI) of 4.78. The structural and docking analysis demonstrated that ClpP CHFM possesses the ability to hydrolyze αS1-casein. [Display omitted] • The growth of Lpb.pentosus CHFM at high temperatures above 50°C. • New strategy for the production of caseinolytic endopeptidase from Lpb.pentosus CHFM. • Sequencing of the ClpP CHFM-encoding gene revealed two conservative substitutions. • Docking analysis demonstrated that ClpP CHFM are capable of hydrolysing αS1-casein. [ABSTRACT FROM AUTHOR]

Campylobacteriosis stands as one of the most frequent bacterial gastroenteritis worldwide necessitating antibiotic treatment in severe cases and the rise of quinolones-resistant Campylobacter jejuni poses a significant challenge. The predominant mechanism of quinolones-resistance in this bacterium involves point mutations in the gyrA , resulting in amino acid substitution from threonine to isoleucine at 86th position, representing more than 90% of mutant DNA gyrase, and aspartic acid to asparagine at 90th position. WQ-3334, a novel quinolone, has demonstrated strong inhibitory activity against various bacteria. This study aims to investigate the effectiveness of WQ-3334, and its analogues, WQ-4064 and WQ-4065, with a unique modification in R1 against quinolones-resistant C. jejuni. The structure-activity relationship of the examined drugs was investigated by measuring IC 50 and their antimicrobial activities were accessed by MIC against C. jejuni strains. Additionally, in silico docking simulations were carried out using the crystal structure of the Escherichia coli DNA gyrase. WQ-3334 exhibited the lowest IC 50 against WT (0.188 ± 0.039 mg/L), T86I (11.0 ± 0.7 mg/L) and D90 N (1.60 ± 0.28 mg/L). Notably, DNA gyrases with T86I substitutions displayed the highest IC 50 values among the examined WQ compounds. Moreover, WQ-3334 demonstrated the lowest MICs against wild-type and mutant strains. The docking simulations further confirmed the interactions between WQ-3334 and DNA gyrases. WQ-3334 with 6-amino-3,5-difluoropyridine-2-yl at R1 severed as a remarkable candidate for the treatment of foodborne diseases caused by quinolones-resistant C. jejuni as shown by the high inhibitory activity against both wild-type and the predominant quinolones-resistant strains. [ABSTRACT FROM AUTHOR]

Testosterone boosters (TB) are multi-ingredient dietary supplements that have gained popularity among athletes and the general population. However, certain ingredients in TB are associated with adverse events. The aim of the present study was to analyze dietary TB supplements available for sale online on shop.bodybuilding.com and amazon.com in ten distribution area markets. We evaluated the top five best-selling TB and the most frequently used ingredients of 50 selected TB and the evidence for their efficacy and safety, as well as legislation, statements in the European Union (EU) and sports organizations such as International Olympic Committee (IOC), International Society of Sports Nutrition (ISSN), Australian Institute of Sport (AIS) and World Anti- Doping Agency (WADA). Among 50 TB, 361 components and 98 ingredients were identified. The following ingredients were included in the final review: fenugreek, D- aspartic acid (DAA), 3,3′-diindolylmethane (DIM) or indole-3-carbinol (I3C), Eurycoma longifolia, Cordyceps spp., and ecdysteroids. In EU an authorized health claims refer to few ingredients in TB, mainly minerals, vitamins. Some ingredients were recognized by international sports organizations such as the ISSN, AIS, and WADA and some were identified as unauthorized ingredients/novel food in the EU. Selected ingredients can possibly increase the risk of endocrine system dysregulation. [ABSTRACT FROM AUTHOR]

Aims: Hyperglycemia is one of the adverse effects of tacrolimus (TAC), but the underlying mechanism is not fully identified.We usedmulti-omics analysis to evaluate the changes in the gut microbiota and metabolic profile of rats with TAC-induced diabetes. Methods: To establish a diabetic animal model, Sprague Dawley rats were divided randomly into two groups. Those in the TAC group received intraperitoneal injections of TAC (3mg/kg) for 8 weeks, and those in the CON group served as the control. 16S rRNA sequencing was used to analyze fecal microbiota. The metabolites of the two groups were detected and analyzed by nontargeted and targeted metabolomics, including amino acids (AAs), bile acids (BAs), and short-chain fatty acids (SCFAs). Results: The rats treated with TAC exhibited hyperglycemia as well as changes in the gut microbiota and metabolites. Specifically, their gut microbiota had significantly higher abundances of Escherichia-Shigella, Enterococcus, and Allobaculum, and significantly lower abundances of Ruminococcus, Akkermansia, and Roseburia. In addition, they had significantly reduced serum levels of AAs including asparagine, aspartic acid, glutamic acid, and methionine. With respect to BAs, they had significantly higher serum levels of taurocholic acid (TCA), and glycochenodeoxycholic acid (GCDCA), but significantly lower levels of taurodeoxycholic acid (TDCA) and tauroursodeoxycholic acid (TUDCA). There were no differences in the levels of SCFAs between the two groups. Correlations existed among glucose metabolism indexes (fasting blood glucose and fasting insulin), gut microbiota (Ruminococcus and Akkermansia), and metabolites (glutamic acid, hydroxyproline, GCDCA, TDCA, and TUDCA). Conclusions: Both AAs and BAs may play crucial roles as signaling molecules in the regulation of TAC-induced diabetes. [ABSTRACT FROM AUTHOR]

Coral skeletons are composites of aragonite and biomolecules. We report the concentrations of 11 amino acids in massive Porites spp. coral skeletons cultured at two temperatures (25 °C and 28 °C) and 3 seawater pCO2 (180, 400 and 750 µatm). Coral skeletal aspartic acid/asparagine (Asx), glutamic acid/glutamine (Glx), glycine, serine and total amino acid concentrations are significantly higher at 28 °C than at 25 °C. Skeletal Asx, Glx, Gly, Ser, Ala, L-Thr and total amino acid are significantly lower at 180 µatm seawater pCO2 compared to 400 µatm, and Ser is reduced at 180 µatm compared to 750 µatm. Concentrations of all skeletal amino acids are significantly inversely related to coral calcification rate but not to calcification media pH. Raman spectroscopy of these and additional specimens indicates that CO3 disorder in the skeletal aragonite lattice is not affected by seawater pCO2 but decreases at the higher temperature. This is contrary to observations in synthetic aragonite where disorder is positively related to the aragonite precipitation rate mediated by either increasing temperature (this study) or increasing Ω (this study and a previous report) and to the concentration of amino acid in the precipitation media (a previous report). We observe no significant relationship between structural disorder and coral calcification rate or skeletal [amino acid]. Both temperature and seawater pCO2 can significantly affect skeletal amino acid composition, and further work is required to clarify how environmental change mediates disorder. [ABSTRACT FROM AUTHOR]

Root-based uptake of inorganic carbon has been suggested as an additional carbon source. Our study aimed to characterize and understand the root-based uptake and fixation mechanisms and their impact on plant growth. 13C-labeled bicarbonate fed to Arabidopsis roots was assimilated into aspartic acid but mainly into sucrose, indicating that the added inorganic carbon was transported to the leaves. A hydroponic treatment was also established for A. thaliana using 2 mM NaHCO3 at pH 5.6, which enhanced the photosynthetic and growth parameters. According to transcriptome sequencing data, the observed enhancement in growth may be orchestrated by trehalose-6-phosphate signaling and supported by augmented nitrogen and sulfur assimilation. The analysis also revealed regulatory and transporter activities, including several nitrate (NRT2.1), and sulfate transporter (SULTR1;1 and SULTR1;2) candidates that could participate in bicarbonate uptake. Different transporters and carbon fixation mutants were assessed. Arabidopsis homologs of SLOW-TYPE ANION CHANNEL 1 (slah3) CARBONIC ANHYDRASE (bca4), and SULFATE TRANSPORTER (sultr1;2) mutants were shown to be inferior to the bicarbonate-treated wild types in several growth and root ultrastructural parameters. Besides, aquaporin genes PIP1;3 and PIP2;6 could play a negative role in the carbon uptake by venting carbon dioxide out of the plant. The findings support the hypothesis that the inorganic carbon is taken up by the root anion channels, mostly transported up to the shoots by the xylem, and fixed there by RuBisCo after the conversion to CO2 by carbonic anhydrases. The process boosts photosynthesis and growth by providing an extra carbon supply. [ABSTRACT FROM AUTHOR]

A new green water treatment agent, a poly(aspartic acid)-modified polymer (PASP/5–AVA), was synthesized using polysuccinimide and 5-aminovaleric acid (5-AVA) in a hybrid system. The structure was characterized, and the scale and corrosion inhibition performance were carried out with standard static scale inhibition and electrochemical methods, respectively. The mechanism was explored using XRD, XPS, SEM, and quantum chemistry calculations. The results indicated that PASP/5–AVA exhibited better scale and corrosion inhibition performance than PASP and maintained efficacy and thermal stability of the scale inhibition effect for a long time. Mechanistic studies indicated that PASP/5–AVA interferes with the normal generation of CaCO3 and CaSO4 scales through lattice distortion and dispersion, respectively; the combined effect of an alkaline environment and terminal electron-withdrawing -COOH groups can induce the stable C- ionic state formation in -CH2- of the extended side chain, thus enhancing its chelating ability for Ca2+ ions. At the same time, the extension of the side chain length also enhances the adsorption ability of the agent on the metal surface, forming a thick film and delaying the corrosion of the metal surface. This study provides the necessary theoretical reference for the design of green scale and corrosion agents. [ABSTRACT FROM AUTHOR]

Korean landrace red peppers (Capsicum annuum var. Subicho), such as the traditional representative Subicho variety, are integral to Korean foods and are often consumed raw or used as a dried powder for cuisine. However, the known vulnerability of local varieties of landrace to biotic stresses can compromise their quality and yield. We employed nuclear magnetic resonance (NMR) spectroscopy coupled with a multivariate analysis to uncover and compare the metabolomic profiles of healthy and biotic-stressed Subicho peppers. We identified 42 metabolites, with significant differences between the groups. The biotic-stressed Subicho red peppers exhibited lower sucrose levels but heightened concentrations of amino acids, particularly branched-chain amino acids (valine, leucine, and isoleucine), suggesting a robust stress resistance mechanism. The biotic-stressed red peppers had increased levels of TCA cycle intermediates (acetic, citric, and succinic acids), nitrogen metabolism-related compounds (alanine, asparagine, and aspartic acid), aromatic amino acids (tyrosine, phenylalanine, and tryptophan), and γ-aminobutyric acid. These findings reveal the unique metabolic adaptations of the Subicho variety, underscoring its potential resilience to biotic stresses. This novel insight into the stress response of the traditional Subicho pepper can inform strategies for developing targeted breeding programs and enhancing the quality and economic returns in the pepper and food industries. [ABSTRACT FROM AUTHOR]

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Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Respiratory complex I is a central metabolic enzyme coupling NADH oxidation and quinone reduction with proton translocation. Despite the knowledge of the structure of the complex, the coupling of both processes is not entirely understood. Here, we use a combination of site‐directed mutagenesis, biochemical assays, and redox‐induced FTIR spectroscopy to demonstrate that the quinone chemistry includes the protonation and deprotonation of a specific, conserved aspartic acid residue in the quinone binding site (D325 on subunit NuoCD in Escherichia coli). Our experimental data support a proposal derived from theoretical considerations that deprotonation of this residue is involved in triggering proton translocation in respiratory complex I. [ABSTRACT FROM AUTHOR]

Magnesium chelatase (MgCh) plays a pivotal role in photosynthesis, catalyzing the insertion of magnesium into protoporphyrin IX (Proto IX), a key intermediate in chlorophyll (Chl) biosynthesis. MgCh is a heteromeric complex composed of the MgCh D subunit (CHLD), the MgCh H subunit (CHLH), and the MgCh I subunit (CHLI). The bright yellow leaves (byl) mutant was obtained through ethyl methanesulfonate (EMS) mutagenesis of the 'FT' Chinese cabbage (Brassica rapa L. ssp. pekinensis) doubled haploid line, whose Chl content, net photosynthetic rate (Pn), and non-photochemical quenching coefficient (NPQ) were decreased, and whose chloroplast development was incomplete. byl recovered to a light green phenotype under weak light conditions. Genetic analysis revealed that the bright yellow leaves phenotype of byl was caused by a single recessive nuclear gene. Using Mutmap sequencing and Kompetitive allele-specific PCR (KASP) identification, BraA01g010040.3.5C, encoding the CHLI subunit of MgCh, was identified as the candidate gene and named Brchli1. A nonsynonymous G-to-A mutation in the Brchli1 exon resulted in the substitution of aspartic acid with asparagine. Brchli1-silenced Chinese cabbage displayed bright yellow leaves with decreased Brchli1 expression. Transiently overexpressed Brchli1 in the byl mutant restored the green leaf phenotype and significantly increased relative Brchli1 expression levels. Both BrCHLI1 and its mutated variant were localized in chloroplasts. Yeast two-hybrid and luciferase complementation imaging assays demonstrated that BrCHLI1 interacted with both BrCHLD and itself. BrCHLI1 mutations did not affect its interaction with BrCHLD. Together, Brchli1 mutations impaired the function of MgCh, providing insights into the molecular mechanism of leaf coloration. [ABSTRACT FROM AUTHOR]

The Canary Islands inhabitants, a recently admixed population with significant North African genetic influence, has the highest incidence of childhood-onset type 1 diabetes (T1D) in Spain and one of the highest in Europe. HLA accounts for half of the genetic risk of T1D. Aims: To characterize the classical HLA-DRB1 and HLA-DQB1 alleles in children from Gran Canaria with and without T1D. Methods: We analyzed classic HLA-DRB1 and HLA-DQB1 alleles in childhood-onset T1D patients (n = 309) and control children without T1D (n = 222) from the island of Gran Canaria. We also analyzed the presence or absence of aspartic acid at position 57 in the HLA-DQB1 gene and arginine at position 52 in the HLA-DQA1 gene. Genotyping of classical HLA-DQB1 and HLA-DRB1 alleles was performed at two-digit resolution using Luminex technology. The chi-square test (or Fisher's exact test) and odds ratio (OR) were computed to assess differences in allele and genotype frequencies between patients and controls. Logistic regression analysis was also used. Results: Mean age at diagnosis of T1D was 7.4 ± 3.6 years (46% female). Mean age of the controls was 7.6 ± 1.1 years (55% female). DRB1*03 (OR = 4.2; p = 2.13–13), DRB1*04 (OR = 6.6; p ≤ 2.00–16), DRB1* 07 (OR = 0.37; p = 9.73–06), DRB1*11 (OR = 0.17; p = 6.72–09), DRB1*12, DRB1*13 (OR = 0.38; p = 1.21–05), DRB1*14 (OR = 0.0; p = 0.0024), DRB1*15 (OR = 0.13; p = 7.78–07) and DRB1*16 (OR = 0.21; p = 0.003) exhibited significant differences in frequency between groups. Among the DQB1* alleles, DQB1*02 (OR: 2.3; p = 5.13–06), DQB1*03 (OR = 1.7; p = 1.89–03), DQB1*05 (OR = 0.64; p = 0.027) and DQB1*06 (OR = 0.19; p = 6.25–14) exhibited significant differences. A total of 58% of the studied HLA-DQB1 genes in our control population lacked aspartic acid at position 57. Conclusions: In this population, the overall distributions of the HLA-DRB1 and HLA-DQB1 alleles are similar to those in other European populations. However, the frequency of the non-Asp-57 HLA-DQB1 molecules is greater than that in other populations with a lower incidence of T1D. Based on genetic, historical and epidemiological data, we propose that a common genetic background might help explain the elevated pediatric T1D incidence in the Canary Islands, North-Africa and middle eastern countries. [ABSTRACT FROM AUTHOR]

This study characterized the bioactive peptides derived from the pokea clam (Batissa violacea celebensis) protein hydrolysate using enzymatic hydrolysis. Fresh pokea clams were analyzed for their proximate composition, revealing moisture content of 86.01%, protein content of 9.10%, lipid content of 6.90%, and ash content of 0.80%. The degree of hydrolysis (DH) increased from 40 to 44% over hydrolysis times of 5 to 7 hours using 4% papain enzyme at pH 7. Peptide concentration rose from 180 to 207mg/ mL during this period. High-performance liquid chromatography (HPLC) analysis revealed significant levels of glutamic acid (6.52%), aspartic acid (4.21%), glycine (3.73%), and lysine (3.20%). These results suggest that the pokea clam protein hydrolysates are a valuable source of bioactive peptides with potential applications in food and health industries, including antioxidant, antihypertensive, and antimicrobial functionalities. [ABSTRACT FROM AUTHOR]

Salt is a potent abiotic stress that arrests plant growth by impairing their physio-biochemical and molecular processes. However, it is unknown how the ABA signaling system and vacuolar-type Na+/H+ antiporter proteins induce stress tolerance in wheat (Triticum aestivum L.) seedlings. The present study aimed to identify salt-responsive proteins and signaling pathways involved in the resistance of wheat to salt stress. We explored the proteome profile, 20 amino acids, 14 carbohydrates, 8 major phytohormones, ion content, and salt tolerance genes in wheat (Triticum aestivum L., cv.) under 200 mM NaCl with control plants for six days. The results showed that amino acids such as alanine, serine, proline, glutamine, and aspartic acid were highly expressed under salt stress compared with control plants, suggesting that amino acids are the main players in salinity tolerance. The ABA signaling system was activated in response to salinity stress through the modulation of protein phosphatase 2C (PP2C) and ABA-responsive element binding factor (ABF), resulting in an ABA-mediated downstream response. Additionally, the vacuolar-type Na+/H+ antiporter was identified as a key protein in salt stress tolerance via compartmentalizing Na+ in the vacuole. Furthermore, a significant increase in the abundance of the 14-3-3 protein was noticed in salt-fed plants, suggesting that this protein plays an important role in Na+ compartmentalization. Moreover, up-regulation of ascorbate peroxidase (APX), glutathione-S-transferase (GST), and thioredoxin-scavenged reactive oxygen species resulted in improved plant growth under salt stress. These data will help to identify salt-responsive proteins that can be used in future breeding programs to develop salt-tolerant varieties. [ABSTRACT FROM AUTHOR]

Spermidine is a naturally occurring polyamine widely utilized in the prevention and treatment of various diseases. Current spermidine biosynthetic methods have problems such as low efficiency and complex multi-enzyme catalysis. Based on sequence-structure-function relationships, we engineered the widely studied homospermidine synthase from Blastochloris viridis (BvHSS) and obtained mutants that could catalyze the production of spermidine from 1,3-diaminopropane and putrescine. The specific activities of BvHSS and the mutants D361E and E232D + D361E (E232D-D) were 8.72, 46.04 and 48.30 U/mg, respectively. The optimal pH for both mutants was 9.0, and the optimal temperature was 50 ◦C. Molecular docking and dynamics simulations revealed that mutating aspartic acid at position 361 to glutamic acid narrowed the substrate binding pocket, promoting stable spermidine production. Conversely, mutating glutamic acid at position 232 to aspartic acid enlarged the substrate channel entrance, facilitating substrate entry into the active pocket and enhancing spermidine generation. In whole-cell catalysis lasting 6 h, D361E and E232D-D synthesized 725.3 and 933.5 mg/L of spermidine, respectively. This study offers a practical approach for single-enzyme catalyzed spermidine synthesis and sheds light on the crucial residues influencing homospermidine synthase catalytic activity in spermidine production. [ABSTRACT FROM AUTHOR]

Coxsackievirus group B3 (CVB3) belongs to the genus Enteroviruses of the family Picornaviridae and is the main pathogen underlying viral myocarditis (VMC). No specific therapeutic is available for this condition. Argininosuccinate synthase 1 (ASS1) is a key enzyme in the urea cycle that converts citrulline and aspartic acid to argininosuccinate. Here, we found that CVB3 and its capsid protein VP2 inhibit the autophagic degradation of ASS1 and that CVB3 consumes citrulline to upregulate ASS1, triggers urea cycle metabolic reprogramming, and then activates macrophages to develop pro-inflammatory polarization, thereby promoting the occurrence and development of VMC. Conversely, citrulline supplementation to prevent depletion can downregulate ASS1, rescue macrophage polarization, and alleviate the pathogenicity of VMC. These findings provide a new perspective on the occurrence and development of VMC, revealing ASS1 as a potential new target for treating this disease. IMPORTANCE Viral myocarditis (VMC) is a common and potentially life-threatening myocardial inflammatory disease, most commonly caused by CVB3 infection. So far, the pathogenesis of VMC caused by CVB3 is mainly focused on two aspects: one is the direct myocardial injury caused by a large number of viral replication in the early stage of infection, and the other is the local immune cell infiltration and inflammatory damage of the myocardium in the adaptive immune response stage. There are few studies on the early innate immunity of CVB3 infection in myocardial tissue, but the appearance of macrophages in the early stage of CVB3 infection suggests that they can play a regulatory role as early innate immune response cells in myocardial tissue. Here, we discovered a possible new mechanism of VMC caused by CVB3, revealed new drug targets for anti-CVB3, and discovered the therapeutic potential of citrulline for VMC. [ABSTRACT FROM AUTHOR]

Background: Lactobacillus plantarum can produce many secondary metabolites, some of which have antibacterial effects. This study aimed to explore the main antimicrobial metabolites of Lactobacillus plantarum LPZN19. Results: The results of antibacterial activity after fermentation for different durations showed that the metabolites from the LPZN19 cell-free supernatant (LCFS) after 24 h had the strongest antibacterial activity, which was confirmed by the highest contents of organic acids and fatty acids in the LCFS after 24 h. Lactic acid, phenyllactic acid, malic acid, aspartic acid, dodecanoic acid and propionic acid were the main differentially abundant metabolites. LCFS was separated by semi-preparative liquid chromatography to obtain 4 antibacterial parts, mainly organic acids such as lactic acid, glycolic acid, and citric acid, and fatty acids such as stearic acid, palmitic acid, and octanoic acid. In addition, fatty glycerides and amino acids with antimicrobial activity were included. Conclusions: Our findings indicate that the main antimicrobial metabolites of L. plantarum LPZN19 include organic acids, fatty acids, fatty glycerides and some amino acids with antimicrobial activity, which not only clarifies the main antimicrobial metabolites of L. plantarum LPZN19 but also provides an effective method for rapid screening of antimicrobial substances. [ABSTRACT FROM AUTHOR]

Formation water scale blocks pipelines and results in oil/gas production decreasing and energy consumption increasing. Many methods have been developed to inhibit scale formation. However, these previous methods are limited by their complications and low efficiency. A new method is proposed in this paper that uses the scale in formation water as a nanomaterial to improve oil recovery via controlling particle size. A series of ligands were synthesized and characterized. Micrometer-CaCO3 was formed and accumulated to form scale of a large size under uncontrolled conditions. The tetradentate ligands (L4) exhibited an excellent capturing yield of Ca2+ (87%). The particle size was very small, but they accumulated to form large particles (approximately 1300 nm) in the presence of Na2CO3. The size of the CaCO3 could be further controlled by poly(aspartic acid) to form sizes of about 700 nm. The flooding test showed that this material effectively improved oil recovery from 55.2% without nano CaCO3 to 61.5% with nano CaCO3. This paves a new pathway for the utilization of Ca2+ in formation water. [ABSTRACT FROM AUTHOR]

This work includes the preparation of Fe3O4 NPs coated with mesoporous silica nanoparticles (MSNs). The combination between two different materials could improve the removal efficiency of pollutants from wastewater. The surface modification of magnetic nanoparticles could reduce the agglomeration. The Fe3O4-MSNs surface was modified with aspartic acid liked with the adsorbent surface via hydrophobic linker (1,4-phenylene diisothiocyanate, PDITC) to effectively remove the methylene blue (MB) dye from the contaminated water. The particles size was ranged between 110 and 160 nm, as estimated by SEM and TEM. The surface zeta potential of the surface was found to be negatively at pH above 2.5. The nanosorbent efficiency was evaluated at different conditions such as pH, contact time and initial MB concentration. The maximum adsorbed amount of the MB was estimated to be 135 mg/g at 200 mg/L MB concentration and 80 min contact time. The adsorption isotherm fits with the Langmuir model and pseudo-second-order kinetics. [ABSTRACT FROM AUTHOR]

SshEstI, a carboxylesterase from the thermoacidophilic archaeon Saccharolobus shibatae , is a member of the hormone-sensitive lipase family that displays slightly alkaliphilic activity with an optimum activity at pH 8.0. In this study, three distinct strategies were explored to confer acidophilic properties to SshEstI. The first strategy involved engineering the oxyanion hole by replacing Gly81 with serine or aspartic acid. The G81S mutant showed optimum activity at pH 7.0, whereas the aspartic acid mutant (G81D) rendered the enzyme slightly acidophilic with optimum activity observed at pH 6.0; however, k cat and k cat / K m values were reduced by these substitutions. The second strategy involved examining the effects of surfactant additives on the pH-activity profiles of SshEstI. The results showed that cetyltrimethylammonium bromide (CTAB) enhanced wild-type enzyme (WT) activity at acidic pH values. In the presence of 0.1 mM CTAB, G81S and G81D were acidophilic enzymes with optimum activity at pH 6.0 and 4.0, respectively, although their enzyme activities were low. The third strategy involved engineering the active site to resemble that of kumamolisin-As (kuma-As), an acidophilic peptidase of the sedolisin family. The catalytic triad of kuma-As was exchanged into SshEstI using site-directed mutagenesis. X-ray crystallographic analysis of the mutants (H274D and H274E) revealed that the potential hydrogen donor–acceptor distances around the active site of WT were fully maintained in these mutants. However, these mutants were inactive at pH 4–8. [ABSTRACT FROM AUTHOR]

Rhizopus oryzae lipase (ROL) is known to present high selectivity in chemical reactions. However, the poor stability of ROL effectively limits its industrial applications. In this study, several immobilization protocols, such as hydrophobic adsorption, covalent immobilization, multi‐point covalent attachment, ionic adsorption/cross‐linking, and ionic interaction, were applied to improve the stability of ROL. Heterogeneous modification of aspartic and glutamic acid residues on the surface of ROL was carried out by 1‐ethyl‐3‐(3‐dimethylaminopropyl) carbodiimide (EDC) to introduce new amine groups with lower pKb. The highest immobilization yield of 89% was achieved for octyl‐agarose, producing specific activity of 45 U/mg, which is 15 folds higher than the specific activity of the soluble enzyme. Improved stability of ROL was observed, in particular for those derivatives obtained by multi‐point covalent attachment of ROL on glyoxyl‐agarose (Gx‐ROL) and aminated ROL on glyoxyl‐agarose (Gx‐NH2‐ROL) by retaining 28%–36% of their initial activities after 24 h incubation at 60°C. Immobilization also altered the co‐solvent stability profile of the immobilized derivatives producing biocatalysts with varied co‐solvent stabilities. Furthermore, utilization of the immobilized preparations in fish oil hydrolysis revealed the selective release of cis‐5,8,11,14,17‐eicosapentaenoic acid (EPA) and cis‐4,7,10,13,16,19‐docosahexaenoic acid (DHA) in favor of EPA. The highest EPA/DHA selectivity of 33 was observed for the hydrophobically immobilized ROL on octyl‐sepharose. [ABSTRACT FROM AUTHOR]

The Black Soldier Fly (BSF; Hermetia illucens) larvae are recognized for their ability to convert diverse organic materials into protein-rich biomass, depending on the substrate they consume. The composition of these substrates can significantly impact the nutrient profile and enzyme activities of the resulting maggot protein extract (MPE). Therefore, this exploratory research aimed to assess the nutrient content, protease, and cellulase activity of MPE obtained from BSF maggots reared on different substrates, with a specific focus on substrates A (comprising restaurant waste and rejected milk), B (layer manure), and C (kitchen waste). The results showed that maggot meal from layer manure had the highest protein content (45.36%) and the lowest fat content (18.44%). Amino acids in maggot meal contained high levels of glutamic acid, aspartic acid, alanine, valine, leucine, and isoleucine. Lauric acids were found in maggot meal from kitchen waste (33.79%), layer manure (32.18%), and restaurant waste and rejected milk (22.94%). Maggot meal from layer manure had the highest oleic acid content (15.13%). The protein concentration of MPE from various substrates ranged from 0.56 to 0.601 mg/ml (at 60% w/v ammonium sulfate saturation) and 0.555 to 0.609 mg/ml (at 70% ammonium sulfate saturation). The protease activity of MPE from layer manure substrates exhibited optimum activity and stability in neutral to alkaline pH, with activity levels of 0.748 U/mg at pH 7.0 and pH 11.0 (at 60% w/v ammonium sulfate saturation) and 0.774 units/mg at 70% w/v ammonium sulfate saturation. The highest cellulase activity was found in MPE from kitchen waste, which remained stable at pH 5.0-11.0. In general, maggots from different substrate sources exhibited distinct nutrient profiles and enzyme activities. Protein extract from maggots grown in layer manure showed the most suitable nutrient profile for use as an alternative source of protein feed and protease enzymes. [ABSTRACT FROM AUTHOR]

Objective: To analyze the effects of arginine-glycine-aspartic acid (RGD) modification on anti-hepatocarcinoma activity of tumstatin peptide 19 (T-19) and to comparatively analyze the effects of tumor suppressor peptide 19 (T-19) and RGD modified-T-19 (RGD-T-19) on the proliferation, invasion, migration of on liver cancer SK-Hep-1 cells. Methods: T-19 and RGD-T-19 were synthesized by Fmoc solid-phase method and separated and identified using high-performance liquid chromatography and mass spectrometry. SK-Hep-1 cells were routinely cultured and treated with 0, 50, 100, 150, 200, and 250 mg/mL of T-19 and RGD-T-19, respectively. The cells were divided into control group (0 mg/mL), 50 mg/mL group, 100 mg/mL group, 150 mg/mL group, 200 mg/mL group, and 250 mg/mL group. CCK-8 assay and clone formation test were used to detect the effects of T-19 and RGD-T-19 on the viability and proliferation of SK-hep-1 cells. The invasion and migration of SK-Hep-1 cells were observed by scratch and Transwell test. The mRNA expression of cellular matrix metalloproteinases MMP-2 and MMP-9 was detected by qPCR. The protein expression of COX-2, MMP-2, MMP-9, TIMP-1, and TIMP-2 was detected by Western blot. Results: The synthesized T-19 and RGD-T-19 were identified to be of high purity by mass spectroscopy. Both T-19 and RGD-T-19 significantly inhibited the proliferation, migration, and invasion abilities of SK-Hep-1 cells, suppressed the protein expression of COX-2 and both the mRNA and protein expression of MMP-2, and MMP-9, but promoted the protein expression of TIMP-1 and TIMP-2 (P < 0.05, P < 0.01, P < 0.001). Notably, the inhibitory or promoting effects of RGD-T-19 were significantly stronger than those of T-19 (P < 0.05). Conclusion: T-19 and RGD-T-19 synthesized by Fmoc solid-phase method were highly pure and eligible. Both T-19 and RGD-T-19 can inhibit the proliferation, invasion, and migration of SK-Hep-1 cells, with better effects of RGD-T-19 than T-19. [ABSTRACT FROM AUTHOR]

Canadian goldenrod (Solidago canadensis L.) is a rhizomatous plant of the Asteraceae family. In folk medicine, Solidago galenic remedies are used for diseases of the kidneys, urinary tract, liver, etc. Externally, goldenrod is used to treat purulent wounds, furunculosis, and gum abscesses as washes and compresses. The aims of this research were to study the yield and chemical composition of essential oil (EO), the anti-inflammatory activity of S. canadensis dry extracts based on its decoction and tincture. In EO (2.8 mL/kg) of S. canadensis were identified and quantified 34 compounds. The principal compounds of the EO from flowering tops of S. canadensis were α-pinene (20.36%), β-copaene (16.16%), bornyl acetate (10.45%), D-limonene (8.21%), and β-elemene (6.80%). In the S. canadensis dry extracts were identified and quantified 20 phenolics (10 flavonoids, 8 hydroxycinnamic acids and 2 phenolic acids) and 14 amino acids, 7 of which are essential. The dominant hydroxycinnamic acids were neochlorogenic and chlorogenic acids, and 4,5-dicaffeoylquinic, 3,5-dicafeylquinic and 3,4-dicafeylquinic acids. The main flavonoids were rutin and isoquercitrin. The main amino acids (more than 1 mg/g) were proline, histidine, serine, alanine, aspartic acid, lysine and glutamic acid. The extracts of S. canadensis were characterized as practically non-toxic substances (toxicity class V). The extracts act on the exudative phase of inflammation. The antiexudative effect of the dry aqueous-alcohol S. canadensis extract was 23.59%, and for the aqueous one –19.26%. The dry aqueous-alcohol S. canadensis extract showed promising anti-inflammatory activity. [ABSTRACT FROM AUTHOR]

This study investigated the physicochemical properties, functionalities, and antioxidant capacities of protein extracts from wild sea cucumber Australostichopus mollis collected from four distinct locations in New Zealand. Protein was extracted from sea cucumber body walls using trypsin enzymatic extraction, followed by cold acetone precipitation. The amino acid analysis revealed high glycine (189.08 mg/g), glutamic acid (119.45 mg/g), and aspartic acid (91.91 mg/g) concentrations in all samples. The essential amino acid indexes of the protein extracts (62.96, average) were higher than the WHO/FAO standard references, indicating the excellent protein quality of A. mollis. Furthermore, protein extracts from A. mollis demonstrated superior emulsifying activity (202.3–349.5 m2/g average) compared to commercial soy and whey protein isolates under all tested pH conditions, and enhanced foaming capacity (109.9–126.4%) and stability (52.7–72%) in neutral and acidic conditions. The extracts also exhibited good solubility, exceeding 70% across pH 3–11. Antioxidant capacities (ABTS and DPPH free radical scavenging activity and ferric reducing antioxidant power) were identified in A. mollis protein extracts for the first time, with clear variations observed among different locations. These findings elucidate the advantageous functional properties of protein extracts from wild New Zealand A. mollis and highlight their potential application as high-quality antioxidant food ingredients. [ABSTRACT FROM AUTHOR]

Cyanobacteria and heterotrophic bacteria show many similarities in their structure but are different based on their nutritional habits. Autotrophic cyanobacteria and heterotrophic bacteria coexist closely in their natural environments and are capable of a variety of interactions (synergistic, neutral, and antagonistic) due to the secretion of growth‐promoting/retarding (toxin) substances by the bacterial partner. In this study, the cyanobacteria Lyngbya aestuarii and its associated bacteria Alcaligenes aquatilis isolated from the mangrove water of Bhitarkanika showed an antagonistic interaction. The growth of axenic and co‐cultured (1:1; cyanobacteria to bacteria) cyanobacteria was examined under photoautotrophic conditions, to evaluate the interactions between the two groups. The bacteria were found to have cellulase and protease activity and were able to obstruct the growth of cyanobacteria under co‐culture conditions. Besides that, the bacteria secrete many allelochemicals like phenol, tannin, amino acids (alanine and aspartic acid), and hydroxamate siderophore to its surroundings which inhibit the growth and metabolism of the cyanobacteria under co‐cultured conditions. Findings from this study indicate its possible application for wastewater management. [ABSTRACT FROM AUTHOR]

BACKGROUND: Higher alcohol acetates (HAAs) are potent aroma‐active esters that impart desirable fruity and floral aromas. However, the conversion of higher alcohol precursors into HAAs is extremely low in winemaking. To investigate the underlying yeast–yeast interaction on targeted improvement of aromatic HAAs, we evaluated fermentation activity, cell viability, amino acid consumption and HAA production when Pichia kluyveri and Saccharomyces cerevisiae were inoculated concurrently or sequentially. RESULTS: Pichia kluyveri PK‐21 possessed the ability to survive and increased HAA level up to 5.2‐fold in mixed fermentation. Such an increment may benefit from the efficient conversion of higher alcohol precursors into HAAs (>27‐fold higher than S. cerevisiae). During mixed fermentation, the two yeasts exhibited crucial interactions regarding cell growth and amino acid competition. Saccharomyces cerevisiae dominated over the co‐inoculated P. kluyveri by efficient uptake of amino acids and biomass production. However, this dominance decreased in sequential fermentation, where P. kluyveri growth increased due to the consumption of preferred amino acids prior to S. cerevisiae. Pearson correlation analysis indicated that phenylalanine and aspartic acid may act as positive amino acids in boosting P. kluyveri growth and HAA production. Laboratory‐scale winemaking validated the fermentation performance of P. kluyveri in sequential inoculum, resulting in a balanced aroma profile with enhanced floral and tropical fruity characteristics in the final wines. CONCLUSION: This study proposes a microbial, non‐genetically engineered approach for targeted increase of HAA production in winemaking and the findings provide new insights into yeast–yeast interactions. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: Energy‐saving and low‐carbon baking processes, as well as the need to determine the flavor‐forming mechanisms of baked dried tofu, are becoming increasingly necessary. The application of emerging catalytic infrared radiation (CIR) technology in baking of dried tofu is considered of high interest due to the low energy consumption and high baking efficiency compared to traditional baking methods. Hence, this study aimed to investigate the evolution of aroma compounds in baked dried tofu during the CIR baking process and reveal relevant relationships between physical qualities, potential flavor precursors and key volatile compounds. RESULTS: The results showed that the surface color of dried tofu gradually turned an appetizing golden yellow color during the rapid heating process, caused by the uniform infrared radiation from the radiant emitters. Meanwhile, the moisture of dried tofu experienced minimal reduction and the hardness of dried tofu gradually increased with the formation of crust on the surface. In addition, 49 volatile compounds were identified by headspace solid‐phase microextraction–gas chromatography–mass spectrometry and 13 substances – 1‐hexanol, 1‐octen‐3‐ol, 1‐pentanol, heptanal, nonanal, hexanal, (E,E)‐2,4‐decadienal, (E,Z)‐2,4‐decadienal, octanal, (E)‐2‐octenal, (E)‐2‐nonenal, 2‐heptanone and 2‐pentylfuran – were confirmed as key aroma compounds. Moreover, the amino acids aspartic acid, glutamic acid, isoleucine, lysine and arginine, and the fatty acids butyric, caprylic, capric, tridecanoic, stearic, oleic and linolenic were responsible for the unique flavor of CIR‐baked dried tofu. CONCLUSION: Consequently, the findings can provide a scientific basis for manufacturers to achieve precise quality control and large‐scale production of CIR‐baked dried tofu products. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The exposure to modifiable risk factors at young ages have been linked to premature fatal and non-fatal cardiovascular and kidney outcomes. The use of urinary metabolomics has shown strong predictability of kidney function and cardiovascular disease (CVD). We therefore determined the associations between estimated glomerular filtration rate (eGFR) and urinary metabolites in young adults with and without CVD risk factors. Apparently healthy Black and White sexes were included (aged 20–30 years) and categorised by the presence or absence of risk factors, i.e., obesity, physical inactivity, smoking, excessive alcohol intake, masked hypertension, hyperglycemia, dyslipidemia and low socio-economic status, forming the CVD risk group (N = 1036), CVD risk clusters (i.e. presenting with 1 CVD risk factor (N = 344), 2 CVD risk factors (N = 360) and 3 + CVD risk factors (N = 332)) and the control group (N = 166). eGFR was calculated with CKD-EPI equations. A targeted metabolomics approach using liquid chromatography-tandem mass spectrometry was used to measure amino acids and acylcarnitines. Lower cystatin C-based eGFR were indicated in the CVD risk group, 2 and 3 + CVD risk clusters compared to the control group (all P ≤ 0.033). In the CVD risk group, eGFR associated positively with histidine, lysine, asparagine, glycine, serine, glutamine, dimethylglycine, threonine, alanine, creatine, cystine, methionine, tyrosine, pyroglutamic acid, leucine/isoleucine, aspartic acid, tryptophan, glutamic acid, free carnitine, acetylcarnitine, propionylcarnitine, isovalerylcarnitine, octanoylcarnitine and decanoylcarnitine (all P ≤ 0.044), with similar results found in the CVD risk clusters, particularly the 2 CVD risk cluster. eGFR was positively associated with metabolites linked to aromatic amino acid and branched-chain amino acid metabolism, energy metabolism and oxidative stress. These findings may indicate altered reabsorption of these metabolites or altered metabolic regulation to preserve renal health in the setting of CVD risk factors at this young age without established CVD. [ABSTRACT FROM AUTHOR]

The current evaluation was conducted to investigate the chemical composition and functional properties of protein hydrolysates from different Satureja species. The major amino acids (mg/100 g protein) in the protein from different Satureja species were arginine (6.06–14.37), asparagine (1.39–17.06), glutamine (2.42–11.60), glutamic acid (6.34–9.32), beta‐aminoisobutyric acid (3.31–10.29), alanine (4.64–9.59), aspartic acid (5.73–9.54), proline (4.25–8.14), leucine (3.63–5.69), serine (2.64–4.83), lysine (1.89–4.56), glycine (0.96–5.27), valine (2.76–4.83), and phenylalanine (2.86–3.75). Protein hydrolysates from Satureja species exhibited comparable antioxidant activity (IC50 = 0.270–0.328 mg/mL), anti‐linoleic acid oxidation (IC50 = 0.231–0.301 mg/mL), anti‐lecithin oxidation (IC50 = 0.198–0.258 mg/mL), anti‐starch oxidation (IC50 = 0.201–0.277 mg/mL), anti‐amylase activity (IC50 = 0.314–0.337 mg/mL), and anti‐lipase activity (IC50 = 0.309–0.369 mg/mL). The physico‐chemical properties of gelatin dispersion were electrical conductivity (1197 microsiemens/cm), osmolarity (190 milliosmol/kg), surface tension (45 mN/m), particle size (179 nm), zeta potential (−48 mV), and viscosity (4.92 mPa.s). Techno‐functional characteristics of freeze‐dried gelatin particles were as follows: water content (7.68%), water solubility (84.57%), water swelling (151.33%), hygroscopicity (38.20%), hydrophobicity (6.50 μg/g), emulsification activity (68.54%), emulsification stability (57.86%), foam expansion activity (56.08%), foam stability (41.84%), oil‐holding capacity (1.96 g/g), and water‐holding capacity (4.45 g/g). Protein hydrolysate causes minor changes in the physico‐chemical and techno‐functional properties of gelatin. The current investigation introduces Satureja protein hydrolysate as a possible functional and techno‐functional ingredient for bioactive food products for treating diabetes and oxidative stress and as a natural preservative for the food industry. [ABSTRACT FROM AUTHOR]

The aim of the experiment was to study the effects of fermented rice protein (FRP), enzymatic hydrolysis fish protein (EHFP), and fish meal (FM) on the digestible energy (DE), metabolizable energy (ME), and ileal digestibility of amino acids in growing pigs. Experiment one: 24 healthy 'Duroc × Landrace × Yorkshire' castrated male pigs with an average body weight of (15.27±1.12) kg were randomly assigned to the control group (basal diet), FRP group (20% FRP), EHFP group (20% EHFP), and FM group (20% FM), with six replicates per group, each replicate with one pig. The total fecal collection method was used to determine the total tract apparent digestibility of energy, metabolizable energy, and gross energy. Experiment two: Twelve 'Duroc × Landrace × Yorkshire' castrated male pigs with an average body weight of (18.36±1.35) kg, fitted with a T-shaped fistulas, were used in a 4×2 Youden square design. They were randomly assigned to the control group (nitrogen-free diet), FRP group (25% FRP), EHFP group (30% EHFP), and FM group (20% FM), with three replicates per group, each replicate with one pig. The indicator method was used to calculate the apparent ileal digestibility (AID) and the standard ileal digestibility (SID) of amino acids. The DE and ME (feeding basis) of pigs in FPR group were 19.28 and 17.64 MJ/kg, the DE and ME (feeding basis) of pigs in EHFP group were 21.93, 19.92 MJ/kg, and the DE and ME (feeding basis) of pigs in FM group were 15.12, 13.48 MJ/kg, respectively. The SID of amino acids for the FRP and EHFP groups were 73.06% to 88.66% and 87.98% to 94.92%, respectively. Both the DE and ME of the FRP and EHFP groups were significantly higher than those of the FM group (P<0.05). Except for methionine, alanine, aspartic acid, and proline, the SID of other amino acids in the EHFP group was significantly higher than that in the FM group (P<0.05), while the SID of methionine in the FRP group was significantly lower than that in the FM group (P<0.05), and the SID of threonine, proline, and tyrosine was significantly lower than that in the FM group (P<0.05). The study indicates that based on the results of digestible energy and amino acid SID, FPR and EHFP can be used as new types of high-quality protein feed in pig production. [ABSTRACT FROM AUTHOR]