Acid Enrichment Research Articles

Localized Amino Acid Enrichment Analysis as a Tool for Understanding Protein Extremophilicity.

Sequence conservation analyses offer us a powerful glimpse of natural selection at work. Standard tools for measuring sequence conservation report conservation as a function of a specific location in a multiple sequence alignment and have proven indispensable in identifying highly constrained features such as active site residues. The advent of large-scale genomic sequencing efforts allows researchers to expand this paradigm and investigate more nuanced relationships between sequence and function. Here, we present a simple tool (SWiLoDD: Sliding Window Localized Differentiation Detection) that allows researchers to analyze local, rather than site-specific, conservation using a sliding window approach. Our tool accepts multiple sequence alignments partitioned based on a biological differentiator and returns alignment position-based, localized differential enrichment metrics for amino acids of choice. We present two case studies of this analysis in action: local-but-diffuse glycine enrichments in the ATPase subunits of thermophilic and psychrophilic bacterial gyrase homologs, and ligand- and interface-specific amino acid enrichments in halophilic bacterial crotonyl-CoA carboxylases/reductases. Though we have described examples of extremophilic bacterial proteins in this study, our tool may be used to investigate any set of homologous sequences from which sub-groups can be meaningfully partitioned. Our results suggest that investigating differential localized conservation in partitioned MSAs will expand our understanding of how sequence conservation and protein function are connected.

Omega-3 and unsaturated Fatty Acid Enrichment of Shrimp Oil: Preparation, Characterization, and its Application in Salad Dressings

The effect of various lipase hydrolytic conditions on DHA/EPA and unsaturated fatty acids (USFAs) enrichment of shrimp (Litopenaeus vannamei) oil (SO) extracted from hepatopancreas was investigated. DHA/EPA and USFAs levels increased (40.96/22.61 and 27.83%, respectively) under optimized hydrolytic conditions of 20 U lipase, DMSO as a solvent (0.2:0.5), DMSO to water for the substrate mixture (SM), and water to SM (0.4:1) for 2 h at 50 °C. n3FAs and USFAs enriched shrimp oil (n3SO) were added to salad dressing (SD) at various concentrations (0, 5, 10, and 15%) (CON, SD5, SD10, and SD15, respectively) to offset the concentration of soybean oil. The addition of n3SO imparted an attractive orange color, enhancing the organoleptic properties of the SD, as indicated by higher likeness scores for color and appearance attributes than CON and commercial SD (CM). Samples added with n3SO exhibited a more uniform pattern and distribution of oil droplets, suggesting the formation of a stable emulsion system. The result was also supported by its enhanced viscoelastic and flow properties than the CON and CM. Overall, DHA/EPA enriched SO could be potential supplement or functional ingredient in SDs or other emulsion related products with superior health benefits.

Empirical assessment of the enrichment-based metagenomic methods in identifying diverse respiratory pathogens.

Probe-based nucleic acid enrichment represents an effective route to enhance the detection capacity of next-generation sequencing (NGS) in a set of clinically diverse and relevant microbial species. In this study, we assessed the effect of the enrichment-based sequencing on identifying respiratory infections using tiling RNA probes targeting 76 respiratory pathogens and sequenced using both Illumina and Oxford Nanopore platforms. Forty respiratory swab samples pre-tested for a panel of respiratory pathogens by qPCR were used to benchmark the sequencing data. We observed a general improvement in sensitivity after enrichment. The overall detection rate increased from 73 to 85% after probe capture detected by Illumina. Moreover, enrichment with probe sets boosted the frequency of unique pathogen reads by 34.6 and 37.8-fold for Illumina DNA and cDNA sequencing, respectively. This also resulted in significant improvements on genome coverage especially in viruses. Despite these advantages, we found that library pooling may cause reads mis-assignment, probably due to crosstalk issues arise from post-capture PCR and from pooled sequencing, thus increasing the risk of bleed-through signal. Taken together, an overall improvement in the breadth and depth of pathogen coverage is achieved using enrichment-based sequencing method. For future applications, automated library processing and pooling-free sequencing could enhance the precision and timeliness of probe enrichment-based clinical metagenomics.

Fatty acids from nutrition sources for preterm infants and their effect on plasma fatty acid profiles

BackgroundIn preterm infants, IV administration of fat is less well tolerated compared to intake via the enteral route, often resulting in hypertriglyceridemia. It is therefore recommended that parenteral fat intake should not exceed 3.5 to 4.0 g/kg/d whereas human milk can provide up to 8 g/kg/d. It is unknown whether such hypertriglyceridemic conditions are caused by a uniform increase of all fatty acids or it is linked to an elevation of distinct fatty acids due to an unbalanced intake. Obviously, both scenarios could potentially influence the formulation of novel lipid solutions for preterm infants. Objective of this exploratory study was to compare fatty acid profiles between a) different nutritional sources and corresponding plasma samples, b) plasma of infants fed breast milk versus those receiving lipid emulsion, and c) plasma of infants with normal versus elevated triglyceride levels.MethodsForty-seven preterm infants < 36 weeks of gestation were included; fatty acid profiles were measured in serum samples and corresponding nutritional sources (breast milk and lipid emulsion) using gas chromatography/mass spectrometry.ResultsCompared to breast milk levels, plasma contained significantly lower C8:0, C10:0, C12:0, C14:0, C19:1n9, C18:3n3 (p < 0.0001). In contrast, relative abundance of C16:0, C18:0 and C20:4n6 was higher in plasma than in corresponding breast milk samples (p < 0.001) and lipid emulsion (p < 0.01). Compared to the corresponding lipid emulsion, the abundance of C18:2n6 and C18:3n3 was significantly lower in plasma (p < 0.001). Fatty acid profiles in plasma of infants fed breast milk compared to lipid emulsion were not markedly different. Hypertriglyceridemic samples showed elevated levels for C18:1n9 and C16:0 when compared with normotriglyceridemic samples.ConclusionsOur study reveals that lipid levels in plasma show both depletion and enrichment of distinct fatty acids which do not seem to be closely related to dietary intake. A more detailed understanding of fatty acid flux rates is needed, like the understanding of amino acid metabolism and is supported by the finding that hypertriglyceridemia might be a state of selective fatty acid accumulation. This would allow to develop more balanced diets for intensive care and potentially improve clinical outcomes.

Highly selective guanidine-linked covalent organic framework for efficient removal of perfluoroalkyl carboxylic acids from water samples

In this study, guanidine-linked covalent organic framework (TPDGCl) was synthesized via a solvothermal method. The presence of guanidine groups in its structure facilitates electrostatic interactions and provides hydrogen bonding sites, enabling the selective enrichment of perfluoroalkyl carboxylic acids (PFCAs) from environmental water samples. The material exhibits rapid kinetic mass transfer, which facilitates the efficient removal of samples containing PFCAs from aqueous solutions within 5 min. Furthermore, TPDGCl exhibits several advantageous properties, including high selectivity for PFCAs, a high adsorption capacity (2005 mg/g), excellent chemical stability, and remarkable recyclability (five cycles). Additionally, density functional theory (DFT) studies have demonstrated that the adsorption of PFCAs on TPDGCl is enhanced by ion exchange, hydrophobic interactions, hydrogen bonding interactions and ordered channel structures. Finally, TPDGCl was used as an adsorbent for dispersive solid-phase extraction (d-SPE), in combination with ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS), to develop an analytical method for the efficient extraction and sensitive detection of PFCAs. The developed method exhibits highly sensitivity, with detection and quantification limits of 0.64–0.85 ng/L and 2.6–3.4 ng/L, respectively. The recoveries of actual water samples ranged from 75.4% to 113.7%. Moreover, TPDGCl effectively reduces the levels of PFCAs in real water samples to less than 70 ng/L within only 1 h. These results indicate that TPDGCl is an effective adsorbent for removing PFCAs from environmental water samples.

Research on the Mechanism of Root Endophytes of Morus alba L. and Fraxinus mandshurica Rupr., Two Host Plants Growing Inonotus hispidus (Bull.) P. Karst., with Metabarcoding and Metabolomics

Inonotus hispidus (Bull.) P. Karst., is a medicinal fungus, which parasitizes broad-leaved tree such as Morus alba L., Fraxinus mandshurica Rupr., and Ulmus macrocarpa Hance. To elucidate the internal relationship between I. hispidus and its hosts, this study analyzed endophytic bacteria and fungi in the roots of M. alba and F. mandshurica growing I. hispidus using the 16S rDNA and ITS high-throughput sequencing technologies; and conducted widely targeted metabolomics research using UPLC-MS/MS. The results showed that Cyanobacteria and unidentified chloroplasts had the highest relative abundance at the phylum and genus levels, respectively. For endophytic fungi, Ascomycota was dominant at the phylum level, while Pleosporales gen Incertae sedis and Oncopodiella were the dominant genera in the roots of M. alba and F. mandshurica, respectively. Widely targeted metabolomics identified 562 differential metabolites and 46 metabolic pathways. Correlation analysis revealed that Xanthobacteraceae, Pseudorhodoplanes, and Bauldia were potential regulators of phenolic acids and phenylpropanoids biosynthesis. Additionally, the genus Oncopodiella was primarily associated with the enrichment of lipids, amino acids, sugars, phenolic acids, and other compounds. This result provides significant insights into the size of the fruiting body, resource development, and active ingredients of I. hispidus from different tree sources.

Modification of hollow microporous organic network with polyethyleneimine for efficient enrichment of phenolic acids from fruit juice samples

Owning to the hydrophobic characteristics of microporous organic networks (MONs), their utilizations still largely limited in non- and weak-polar analytes. To expend their applications, here we reported the synthesis of a novel hollowed H-MON-PEI1800–2 composite via sacrifice template method and subsequent modification with polyethyleneimine (PEI) for efficient solid phase extraction of polar and ionic phenolic acid (PAs) from fruit juice samples. H-MON-PEI1800–2 exhibits large surface area, rapid extraction kinetics, remarkable chemical and thermal stabilities, and provides synergistic electrostatic, π-π, hydrogen bonding, and hydrophobic interaction sites for PAs. The developed method owns low limit of detection, wide linear range, large enrichment factors, and good reusability. The recoveries of H-MON-PEI1800–2 for PAs are 1–3 orders of magnitude higher than those of commercial adsorbents like activated carbon, C18 and Oasis HLB. This work highlights the prospects of functional H-MONs for enriching polar and ionic targets from complex sample matrices.

Mimicking a Cellular Crowding Environment for Enzyme-Free Paper-Based Nucleic Acid Tests at the Point of Care.

Point of care (PoC) nucleic acid amplification tests (NAATs) are a cornerstone of public health, providing the earliest and most accurate diagnostic method for many communicable diseases in the same location where the patient receives treatment. Communicable diseases, such as human immunodeficiency virus (HIV), disproportionately impact low-resource communities where NAATs are often unobtainable due to the resource-intensive enzymes that drive the tests. Enzyme-free nucleic acid detection methods, such as hybridization chain reaction (HCR), use DNA secondary structures for self-driven amplification schemes, producing large DNA nanostructures, capable of single-molecule detection in cellulo. These thermodynamically driven DNA-based tests have struggled to penetrate the PoC diagnostic field due to their inadequate limits of detection or complex workflows. Here, we present a proof-of-concept NAAT that combines HCR-based amplification of a target nucleic acid sequence with paper-based nucleic acid filtration and enrichment capable of detecting sub-pM levels of synthetic DNA. We reconstruct the favorable hybridization conditions of an in cellulo reaction in vitro by incubating HCR in an evaporating, microvolume environment containing poly(ethylene glycol) as a crowding agent. We demonstrate that the kinetics and thermodynamics of DNA-DNA and DNA-RNA hybridization is enhanced by the dynamic evaporating environment and inclusion of crowding agents, bringing HCR closer to meeting PoC NAAT needs.

Temperature-Dependent Metabolic Interactions Between Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus in Milk Fermentation: Insights from GC-IMS Metabolomics

Streptococcus (S.) thermophilus and Lactobacillus (L.) delbrueckii ssp. bulgaricus are widely used as a combined starter culture for milk fermentation, often at temperatures of 37°C and 42°C. To investigate the metabolic interplay between these 2 species during the fermentation process, this study examined the growth and fermentation characteristics of different S. thermophilus strains cocultured with L. delbrueckii ssp. bulgaricus ND02 at these 2 temperature conditions. Gas chromatography-ion mobility spectrometry (GC-IMS) metabolomics was employed to analyze changes in the milk metabolome during 3 key fermentation stages: initiation (F0, pH 6.50 ± 0.02), curdling (F1, pH 5.20 ± 0.02), and endpoint (F2, pH 4.50 ± 0.02). The results showed that 42°C fermentation promoted rapid bacterial growth, with significantly reduced fermentation time compared with 37°C. Interestingly, 37°C fermentation favored the enrichment of volatile fatty acids like 2-methylpropanoic acid, 3-methylbutanoic acid, and ethyl acetate. In contrast, 42°C fermentation led to increased levels of ketones such as acetone, 2-hexanone, 2-pentanone, and 2-heptanone. Sensory evaluation indicated that the 42°C fermented milk had higher overall scores. Discriminatory flavor metabolites were more abundant during the later fermentation stage (F1 to F2), while the underlying metabolic pathways became increasingly active. These findings provide insights into the dynamic changes in volatile metabolite profiles of fermented milk produced under different temperature and time conditions using varied starter culture combinations. The results are valuable for optimizing dairy fermentation processes and product quality.

Modeling of enzymatic transesterification for omega-3 fatty acids enrichment in fish oil

Mathematical models of transesterification commonly assume that oil is a mixture of triacylglycerols, where each component has only one type of acid attached. This article aims to show how a different assumption on acid distribution affects the results of acylglycerols fraction composition. Experiments of fish oil ethanolysis have been performed at different enzyme loadings and ethanol concentrations, leading to enrichments from 35 % to 52 % of ω3 mass fraction in acylglycerols, by losing 12.1 % of ω3 as ethyl esters. A kinetic model is developed assuming both all acids of the same type on each acylglycerol and all acids randomly distributed on the available positions. The two different assumptions showed strong discrepancies on the acylglycerols fraction compositions predictions, demonstrating how the initial fatty acids distribution is important when an accurate description of the acylglycerols fraction is desired.

Investigating the availability of omega-3 fatty acid from different sources and its effect on table eggs

The impact of three different commercial omega-3 fortifying agents on the growth performance, egg weight, egg production, and omega-3 fatty acid enrichment of white table eggs in layers was investigated. The experiment involved 12,000-layer birds randomly divided into four groups, with each group replicated three times and consisting of 1000 birds per replicate. The three groups, namely LP, AG, and DD, were supplemented with omega-3 fortifying agents LinPro, All-G-Rich, and DHA-gold, respectively, while the fourth group NC served as a negative control without omega-3 fortifying agent supplementation. The experiment commenced after the 25th week of age and lasted for a period of four weeks in a completely randomized design. Egg weight and egg production were recorded weekly, while the omega-3 fatty acid content of the white eggs was determined at the end of the 30-day trial after the 25th week of age. The supplementation of different omega-3 fortifying agents significantly impacted feed intake, with notable differences observed among weekly and overall means. Birds supplemented with LinPro consumed less feed during the 2nd and 4th week of the trial compared to the control, resulting in an overall reduction of 1.1 g/chick in feed intake. However, supplementation did not significantly affect the body weight of layers throughout the trial, nor did it impact egg weight or production. Nevertheless, the omega-3 fortifying agents had a significant effect on the omega-3 fatty acid content of the white table eggs in layers. LinPro supplementation notably increased α-linolenic acid (18:3; ALA) and eicosapentaenoic acid (20:5; EPA) levels, while DHA-Gold resulted in the highest docosahexaenoic acid (22:6; DHA) content. Total fatty acid content was highest in eggs from layers supplemented with LinPro, followed by DHA-Gold and All-G-Rich, with the lowest levels observed in the control group. These findings suggest that dietary supplementation of LinPro in layer diets post the 25th week of age could effectively enhance the omega-3 fatty acid content of white table eggs without compromising feed intake, body weight, egg weight, or egg production.

The effect of dietary omega-6 fatty acid enrichment in rodent models of military-relevant acute traumatic psychological stress and traumatic brain injury

The effect of dietary omega-6 fatty acid enrichment in rodent models of military-relevant acute traumatic psychological stress and traumatic brain injury

Non-Targeted Metabolomics Analysis of γ-Aminobutyric Acid Enrichment in Germinated Maize Induced by Pulsed Light.

Pulsed light is an emerging technique in plant physiology recognized for its ability to enhance germination and accumulate γ-aminobutyric acid in maize. Pulsed light involves exposing plants to brief, high-intensity bursts of light, which can enhance photosynthesis, improve growth, and increase resistance to environmental stresses. Despite its promising potential, the specific metabolic changes leading to γ-aminobutyric acid enrichment in maize induced by pulsed light are not fully understood. This study addresses this gap by quantifying key nutrients and γ-aminobutyric acid-related compounds during maize germination and investigating the underlying mechanisms using non-targeted metabolomics. Our findings indicate that pulsed light significantly promotes maize germination and accelerates the hydrolysis of proteins, sugars, and lipids. This acceleration is likely due to the activation of enzymes involved in these metabolic pathways. Additionally, pulsed light markedly increases the content of glutamic acid and the activity of glutamate decarboxylase, which are crucial for γ-aminobutyric acid synthesis. Moreover, pulsed light significantly reduces the activity of γ-aminobutyric transaminase, thereby inhibiting γ-aminobutyric acid decomposition and resulting in a substantial increase in γ-aminobutyric acid content, with a 27.20% increase observed in germinated maize following pulsed light treatment. Metabolomic analysis further revealed enrichment of metabolic pathways associated with γ-aminobutyric acid, including amino acid metabolism, carbohydrate metabolism, plant hormone signal transduction, energy metabolism, pyrimidine metabolism, and ABC transporters. In conclusion, pulsed light is a robust and efficient method for producing sprouted maize with a high γ-aminobutyric acid content. This technique provides a novel approach for developing sprouted cereal foods with enhanced nutritional profiles, leveraging the physiological benefits of γ-aminobutyric acid, which include stress alleviation and potential health benefits for humans.

In Situ Colorimetric LAMP Based on One-Step Modified Filter Paper to Screen Human Papillomavirus (HPV)16/18 from Clinical Samples.

Cervical cancer is among the most common malignant tumors in women. The development of rapid screening techniques plays an important role in early screening for cancer treatment. We have developed an HPV screening method, which effectively combines the high-efficiency nucleic acid enrichment of chitosan-modified filter paper and the rapid visual detectability of colorimetric LAMP, along with the enhancement of the tolerance ability of the pH-sensitive LAMP reagent to acidic original samples, making the detection of HPV 16/18 easy to carry out and reliable, which is helpful for the epidemiological prevention and control strategies of HPV-induced cancer. This technique can simultaneously exhibit the "in situ amplification" capability of chitosan-modified filter paper and the nontemperature cycle dependence of visual LAMP detection. Therefore, DNA extraction and amplification can be performed efficiently and quickly within a single reaction where all DNA is concentrated in the QF paper disc. By embedding amino-modified filter paper into the plastic chip, a simple and reliable disposable chip was prepared for rapid HPV16 and HPV18 detection from clinical endometrial samples, and the results were 100% consistent with clinical diagnosis. More importantly, even after the sample was diluted 100-fold, HPV16/18-infected cells could be accurately identified, showing the advantages of the system in early cancer screening. Moreover, for endometrial samples containing plenty of cells, the filter paper could be used to enrich cells by filtration, preventing the acidic fluid from impacting pH-induced colorimetric LAMP detection and realizing direct amplification for HPV identification without nucleic acid extraction. This easy-to-operate system that can analyze a wide range of samples will be suitable for routine on-site HPV screening, dramatically extending the applications and utility for rapid, near-patient nucleic acid testing.

Exploring the effect and mechanism of Hippophae rhamnoides L. triterpenoid acids on improving NAFLD based on network pharmacology and experimental validation in vivo and in vitro

Ethnopharmacological relevanceSea buckthorn (Hippophae rhamnoides L.) is a traditional Chinese medicinal and possesses a rich medical history in terms of treating gastric disorders, sputum and cough and liver injuries in oriental medicinal system. By reason of the complicated chemical constituents, the material basis and potential pharmacological mechanism of sea buckthorn acting on Non-alcoholic fatty liver disease (NAFLD) has not been clearly elucidated. Aim of the studyTo explore the pharmacological efficacy and underlying mechanism of sea buckthorn triterpenoid acid enrichment (STE) in the treatment of NAFLD. Materials and methodsThe approaches of Network pharmacology and experiment validation in vitro and in vivo were applied in this study. Firstly, targets of triterpenoid acid compounds and NAFLD were collected from databases. The crucial targets were screened by the construction of protein-protein interaction (PPI) network. Furthermore, the potential signaling pathways and targets affected by STE was predicted by GO together with KEGG enrichment analysis. Finally, the experiment validation was carried out through high-fat feeding NAFLD mice and lipid accumulation HepG2 cell model. Lipids and liver related biochemical indicators were determined, Oil Red O and H&E staining were employed to observe fat accumulation. In addition, the expression levels of proteins of key target and signal pathway anticipated in network pharmacology were detected to elaborated its action mechanism. ResultsA total of 180 intersecting potential targets for enhancing NAFLD with STE were eventually identified. 6 key targets including AKT1, TNF, IL6, INS, JUN, STAT3 and TP53 were further identified and the AMPK-SREBP1 pathway was enriched. Animal experiment result showed that STE treatment could significantly reduce the levels of TG, TC, LDL-C, ALT and AST, increase the levels of HDL-C in serum, and improve lipid accumulation of epididymal fat and liver. The results of the lipid accumulation cell model indicated that STE and key compound oleanolic acid could diminish intracellular lipid levels of TG, TC, LDL-C and number of lipid droplets. Western blot results showed that the above beneficial effects could be achieved by regulating the expression of p-AMPK/AMPK, SREBP1, FAS, ACC, SCD protein. ConclusionThis study confirmed the effect of STE on improving NAFLD and the potential action mechanism was involved in the regulation of the AMPK-SREBP1 pathway.

The co-assembly of spike silica nanoparticles with high affinity to nucleic acid for airborne virus detection

The global pandemic of coronavirus disease 2019 (COVID-19) highlights the shortcomings of the current testing paradigm for viral disease diagnostics. Though the Polymerase Chain Reaction (PCR) technique is currently used for nucleic acid detection in liquid samples, its application in airborne virus has not yet been developed, due to low viral load in the air, lack of efficient capture probe and supporting equipment. Herein, we developed an ultrasensitive biosensing nanoplatform for airborne virus detection. The extraction and concentration of nucleic acid from test samples has been accomplished by novel spike silica nanoparticles (SSNPs)-based nucleic acid capture probe with high spike length to nanoparticle diameter ratio and appropriate surface potential. When integrated with air sampler and Quantitative Real-Time PCR (qPCR) equipment, nucleic acid enrichment can be achieved significantly. Our results demonstrated a successful detection of the virus in the air with the limit of detection (LoD) of 500 copies/L, which greatly surpasses the LoD of 1 × 106 copies/L. This detection method effectively addresses the obstacle posed by the low abundance of pathogens in the environment and could be applied for the detection of pathogens in air or water, aiming to achieve the goal of disease prevention and control prior to its onset.

Valine administration in the hypothalamus alters the brain and plasma metabolome in rainbow trout.

Central administration of valine has been shown to cause hyperphagia in fish. Although mechanistic target of rapamycin (mTOR) is involved in this response, the contributions to feed intake of central and peripheral metabolite changes due to excess valine are unknown. Here, we investigated whether intracerebroventricular injection of valine modulates central and peripheral metabolite profiles and may provide insights into feeding response in fish. Juvenile rainbow trout (Oncorhynchus mykiss) were administered an intracerebroventricular injection of valine (10 µg·µL-1 at 1 μL·100·g-1 body wt), and the metabolite profile in plasma, hypothalamus, and rest of the brain (composing of telencephalon, optic tectum, cerebellum, and medulla oblongata) was carried out by liquid chromatography-mass spectrometry (LC/MS)-based metabolomics. Valine administration led to a spatially distinct metabolite profile at 1 h postinjection in the brain: enrichment of amino acid metabolism and energy production pathways in the rest of the brain but not in hypothalamus. This suggests a role for extrahypothalamic input in the regulation of feed intake. Also, there was enrichment of several amino acids, including tyrosine, proline, valine, phenylalanine, and methionine, in plasma in response to valine. Changes in liver transcript abundance and protein expression reflect an increased metabolic capacity, including energy production from glucose and fatty acids, and a lower protein kinase B (Akt) phosphorylation in the valine group. Altogether, valine intracerebroventricular administration affects central and peripheral metabolism in rainbow trout, and we propose a role for the altered metabolite profile in modulating the feeding response to this branched-chain amino acid.NEW & NOTEWORTHY Valine causes hyperphagia in fish when it is centrally administered; however, the exact mechanisms are far from clear. We tested how intracerebroventricular injection of valine in rainbow trout affected the brain and plasma metabolome. The metabolite changes in response to valine were more evident in the rest of the brain compared with the hypothalamus. Furthermore, we demonstrated for the first time that central valine administration affects peripheral metabolism in rainbow trout.

Optimized extraction, enrichment, identification and hypoglycemic effects of triterpenoid acids from Hippophae rhamnoides L pomace

The Hippophae rhamnoides L. pomace was generated in the production process for juice, wine of food industry. To expand the application of pomace, the extraction process optimization, enrichment and identification of triterpene acids were performed in this study. The extraction yield was 14.87% under optimal ultrasound-assisted extraction techniques performed via response surface methodology. The extract was subsequently purified to obtain the triterpenoid acid enrichment fraction (TPF) with the content of 75.23% ± 1.45%. 13 triterpenoid acids were identified via UPLC-Triple-TOF MS/MS and further semi-quantified through comparison with triterpenoid acid standards. TPF exhibited a strong inhibitory effect on α-glucosidase with IC50 value of 5.027 ± 0.375 μg/mL, as determined via enzyme inhibition experiment and molecular docking. Additionally, the TPF significantly reduced postprandial glucose levels, as revealed via carbohydrate tolerance tests, as well as ameliorate serum lipid profiles. Therefore, pomace may be a promising resource of functional food components with therapeutic and commercial values.

Utilization of Fusarium Solani lipase for enrichment of polyunsaturated Omega-3 fatty acids.

Omega-3 fatty acids, such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), offer numerous health benefits. Enriching these fatty acids in fish oil using cost-effective methods, like lipase application, has been studied extensively. This research aimed to investigate F. solani as a potential lipase producer and compare its efficacy in enhancing polyunsaturated omega-3 fatty acids with commercial lipases. Submerged fermentation with coconut oil yielded Lipase F2, showing remarkable activity (215.68 U/mL). Lipase F2 remained stable at pH 8.0 (activity: 93.84 U/mL) and active between 35 and 70°C, with optimal stability at 35°C. It exhibited resistance to various surfactants and ions, showing no cytotoxic activity in vitro, crucial for its application in the food and pharmaceutical industries. Lipase F2 efficiently enriched EPA and DHA in fish oil, reaching 22.1mol% DHA and 23.8mol% EPA. These results underscore the economic viability and efficacy of Lipase F2, a partially purified enzyme obtained using low-cost techniques, demonstrating remarkable stability and resistance to diverse conditions. Its performance was comparable to highly pure commercially available enzymes in omega-3 production. These findings highlight the potential of F. solani as a promising lipase source, offering opportunities for economically producing omega-3 and advancing biotechnological applications in the food and supplements industry.

Preparation of microelectrode based on molecularly imprinted monolith using ionic liquids as functional monomers for specific separation and enrichment of phenolic acids

Efficient and specific isolation and capture of phenolic acids (PAs) in complex samples is challenging due to its high polarity. In this study, combining the merits of porous monolith, ionic liquids, molecularly imprinted polymer and electroenhanced solid-phase microextraction (EE-SPME), a new sample pretreatment method was developed for the selective isolation and extraction of PAs. Using vanillic acid (VA) as template molecule, mixed ionic liquids including 1-allyl-3-methylimidazoliumbis[(trifluoromethy)sulfonyl]imide and N,N,N-trimethyl-1-(4-vinylphenyl)methanaminium chloride were chosen as dual functional monomers, a molecularly imprinted monolith-based microelectrode (MBM) was in-situ fabricated. Under the EE-SPME format, the extraction behaviors and specific recognition performance of MBM towards VA and its structural analogues were investigated in detail. Results revealed that the exertion of electric field during extraction period increased the imprinted factors from 1.57–1.77 to 1.87–2.23. Under the beneficial parameters, a sensitive and reliable approach for the quantification of PAs contents in water and fruit juice samples by the combination of MBM/EE-SPME with HPLC technique was developed. The achieved limits of detection ranging from 0.012 μg/L to 0.11 μg/L and 0.042 μg/L to 0.15 μg/L for waters and juices, respectively, and the recoveries with different spiked concentrations in actual sample were 83.1–110 %. In comparison with the existing approaches, the established method presented some characteristics in the analysis of PAs, such as simplicity, high cost-effectiveness, good anti-interference performance, satisfactory sensitivity and low consumption of solvent.