-
Antioxidants (Basel, Switzerland) Feb 2024International provenance trials are a hot topic in forestry, and in light of climate change, the search for more resilient beech provenances and their assisted migration...
International provenance trials are a hot topic in forestry, and in light of climate change, the search for more resilient beech provenances and their assisted migration is one of the challenges of climate-smart forestry. The main aim of the study was to determine intraspecific variability in European beech ( L.) among 11 beech provenances according to total antioxidant capacities estimated by various assays, such as DPPH (2,2-diphenyl-1-picrylhydrazyl), ABTS (2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic) acid), FRAP (ferric reducing antioxidant power) assay, and radical scavenging capacity against nitric oxide (RSC-NO assays), as well as osmolyte content, primarily individual polyamines (putrescine, spermidine, and spermine), and free proline content. Polyamine amounts were quantified by using HPLC coupled with fluorescent detection after dansylation pretreatment. The highest values for radical scavenger capacity assays (ABTS, DPPH, and FRAP) were measured in the German provenances DE47 and DE49. Also, the highest NO inhibition capacity was found in the provenance DE49, while the highest content of proline (PRO), total phenolic content (TPC), and total flavonoid content (TFC) was recorded in DE47. The Austrian AT56 and German provenance DE49 were most abundant in total polyamines. This research underlines the importance of the application of common antioxidant assays as well as osmolyte quantification as a criterion for the selection of climate-ready beech provenances for sustainable forest management.
PubMed: 38397825
DOI: 10.3390/antiox13020227 -
Foods (Basel, Switzerland) Feb 2024Ripened sheep sausages are widely consumed in Italy, particularly in Sardinia. Despite their driving role in flavor and color development, coagulase-negative...
Ripened sheep sausages are widely consumed in Italy, particularly in Sardinia. Despite their driving role in flavor and color development, coagulase-negative staphylococci in these products have been rarely investigated. A total of 70 CoNS cultures isolated from Sardinian sheep sausages were characterized by rep-PCR and M13-RAPD typing and identified by 16S rDNA sequencing. and accounted for more than 70% of the total isolates, whilst (8.5%), (2.8%), and (2.8%) were less represented. The genes encoding the synthesis of putrescine, tyramine, cadaverine, and histamine were evaluated by PCR. None of the strains hosted genes for decarboxylases, except one strain that was potentially a tyramine-producer. Antibiotic resistance was evaluated, along with nitrate reductase, lipolytic, and proteolytic activity, in a pool of selected cultures. Resistance to the primary antibiotics was rather widespread. , , and strains were all resistant to amoxicillin and kanamycin. strains were sensitive to all tested antibiotics. strains were all resistant to penicillin B. Conversely, all strains were resistant to both ampicillin and penicillin B, and four out of five strains exhibited tetracycline resistance. The high variability in the production of sheep sausages makes the search for adjunct cultures of crucial relevance. According to this perspective, the characterization of the autochthonous CSN population represents the first step to approach a starter selection.
PubMed: 38397610
DOI: 10.3390/foods13040633 -
Journal of Dairy Science Jul 2024Cheese is a food in which toxic concentrations of biogenic amines (BA) may be reached, mainly as a consequence of the decarboxylation of determined amino acids by...
Cheese is a food in which toxic concentrations of biogenic amines (BA) may be reached, mainly as a consequence of the decarboxylation of determined amino acids by certain lactic acid bacteria (LAB). To maintain the food safety of cheese, environmentally friendly strategies are needed that specifically prevent the growth of BA-producing LAB and the accumulation of BA. The bacteriocins produced by LAB are natural compounds with great potential as food biopreservatives. This work examines the antimicrobial potential of 7 bacteriocin-containing, cell-free supernatants (CFS: coagulin A-CFS, enterocin A-CFS, enterocin P-CFS, lacticin 481-CFS, nisin A-CFS, nisin Z-CFS and plantaricin A-CFS) produced by LAB against 48 strains of the LAB species largely responsible for the accumulation of the most important BA in cheese, that is, histamine, tyramine, and putrescine. Susceptibility to the different CFS was strain-dependent. The histamine-producing species with the broadest sensitivity spectrum were Lentilactobacillus parabuchneri (the species mainly responsible for the accumulation of histamine in cheese) and Pediococcus parvulus. The tyramine-producing species with the broadest sensitivity spectrum was Enterococcus faecium, and Enterococcus faecalis and Enterococcus hirae were among the most sensitive putrescine producers. Nisin A-CFS was active against 31 of the 48 BA-producing strains (the broadest antimicrobial spectrum recorded). Moreover, commercial nisin A prevented biofilm formation by 67% of the BA-producing, biofilm-forming LAB strains. These findings underscore the potential of bacteriocins in the control of BA-producing LAB and support the use of nisin A as a food-grade biopreservative for keeping BA-producing LAB in check and reducing BA accumulation in cheese.
Topics: Cheese; Bacteriocins; Biogenic Amines; Nisin; Biofilms; Lactobacillales; Anti-Infective Agents; Food Microbiology
PubMed: 38395395
DOI: 10.3168/jds.2023-24358 -
Heliyon Feb 2024This study was conducted to mitigate the food safety risks related to biogenic amine (BA) by reducing the BA content in using applicable food additives. In -...
This study was conducted to mitigate the food safety risks related to biogenic amine (BA) by reducing the BA content in using applicable food additives. In - experiments, of the additives tested, tartaric acid (TA), potassium sorbate (PS), and sodium benzoate (SB) considerably inhibited tyramine production of strains of spp. and while less affecting their growth. In addition to these three additives, two additives, glycine (GL) and nicotinic acid (NA), reported to have significant inhibitory effects in previous studies, were applied to the fermentation with prolific tyramine-producing strains of and . The content of tyramine in the samples treated with TA, PS, SB, GL, and NA was significantly reduced by 27.5%, 50.7%, 51.4%, 76.1%, and 100.0%, respectively, compared to the control sample. Additionally, the content of polyamines (putrescine, cadaverine, spermidine, and spermine) in the GL-treated sample was reduced by 42.6%-62.4%. The mode of action could be attributed to inhibiting the bacterial decarboxylase activity and/or growth. Consequently, excluding NA that interfered with fermentation, GL was the most outstanding additive with an inhibitory effect on tyramine formation in food, followed by SB and PS, all of which showed a more than 50% reduction. Therefore, the use of appropriate additives could be one of the promising strategies to avoid the food safety issues implicated in BAs in .
PubMed: 38379996
DOI: 10.1016/j.heliyon.2024.e26135 -
Cell Communication and Signaling : CCS Feb 2024Malaria remains a global health burden, and the emergence and increasing spread of drug resistance to current antimalarials poses a major challenge to malaria control....
BACKGROUND
Malaria remains a global health burden, and the emergence and increasing spread of drug resistance to current antimalarials poses a major challenge to malaria control. There is an urgent need to find new drugs or strategies to alleviate this predicament. Celastrol (Cel) is an extensively studied natural bioactive compound that has shown potentially promising antimalarial activity, but its antimalarial mechanism remains largely elusive.
METHODS
We first established the Plasmodium berghei ANKA-infected C57BL/6 mouse model and systematically evaluated the antimalarial effects of Cel in conjunction with in vitro culture of Plasmodium falciparum. The potential antimalarial targets of Cel were then identified using a Cel activity probe based on the activity-based protein profiling (ABPP) technology. Subsequently, the antimalarial mechanism was analyzed by integrating with proteomics and transcriptomics. The binding of Cel to the identified key target proteins was verified by a series of biochemical experiments and functional assays.
RESULTS
The results of the pharmacodynamic assay showed that Cel has favorable antimalarial activity both in vivo and in vitro. The ABPP-based target profiling showed that Cel can bind to a number of proteins in the parasite. Among the 31 identified potential target proteins of Cel, PfSpdsyn and PfEGF1-α were verified to be two critical target proteins, suggesting the role of Cel in interfering with the de novo synthesis of spermidine and proteins of the parasite, thus exerting its antimalarial effects.
CONCLUSIONS
In conclusion, this study reports for the first time the potential antimalarial targets and mechanism of action of Cel using the ABPP strategy. Our work not only support the expansion of Cel as a potential antimalarial agent or adjuvant, but also establishes the necessary theoretical basis for the development of potential antimalarial drugs with pentacyclic triterpenoid structures, as represented by Cel. Video Abstract.
Topics: Animals; Mice; Antimalarials; Spermidine; Mice, Inbred C57BL; Malaria; Pentacyclic Triterpenes
PubMed: 38378659
DOI: 10.1186/s12964-023-01409-5 -
Poultry Science Apr 2024The objective of this study was to investigate the effects of sex on meat quality and the composition of amino and fatty acids in the breast muscles of White King pigeon...
The objective of this study was to investigate the effects of sex on meat quality and the composition of amino and fatty acids in the breast muscles of White King pigeon squabs. Untargeted metabolomics was also conducted to distinguish the metabolic composition of plasma in different sexes. Compared with male squabs, female squabs had greater intramuscular fat (IMF) deposition and lower myofiber diameter and hydroxyproline content, leading to a lower shear force. Female squabs also had higher monounsaturated fatty acid and lower n-6 and n-3 polyunsaturated fatty acid proportions in the breast muscle, and had greater lipogenesis capacity via upregulation of PPARγ, FAS and LPL gene expression. Moreover, female squabs had lower inosine 5'-monophosphate, essential, free and sweet-tasting amino acid contents. Furthermore, Spearman's correlations between the differential plasma metabolites and key meat parameters were assessed, and putrescine, N-acetylglutamic acid, phophatidylcholine (18:0/P-16:0) and trimethylamine N-oxide were found to contribute to meat quality. In summary, the breast meat of male squabs may have better nutritional value than that of females, but it may inferior in terms of sensory properties, which can be attributed to the lower IMF content and higher shear force value. Our findings enhance our understanding of sex variation in squab meat quality, providing a basis for future research on pigeon breeding.
Topics: Female; Male; Animals; Fatty Acids; Amino Acids; Muscle, Skeletal; Chickens; Meat; Metabolome
PubMed: 38377688
DOI: 10.1016/j.psj.2024.103524 -
Molecular Horticulture Feb 2024Putrescine plays a role in superficial scald development during the cold storage of pear fruit. However, the molecular mechanism behind this phenomenon has not been...
Putrescine plays a role in superficial scald development during the cold storage of pear fruit. However, the molecular mechanism behind this phenomenon has not been un-fully clarified until recently. In this study, a conjoint analysis of metabolites and gene expression profiles in the putrescine-metabolic pathway of P. bretschneideri Rehd. fruit followed by experimental validation revealed that PbrADC1, forming a homodimer in the chloroplast, was involved in putrescine biosynthesis and thus fruit chilling resistance. Additionally, the substrate-binding residue Cys in PbrADC1, whose activity was modified by HO, played a crucial role in arginine decarboxylation into agmatine. Through a combined analysis of the distribution of cis-acting elements in the PbrADC1 promoter as well as the expression profiles of related transcription factors (TFs), several TFs were identified as upstream regulators of PbrADC1 gene. Further investigation revealed that the nuclear PbrWRKY62 could directly bind to the W-box elements in the PbrADC1 promoter, activate its expression, enhance putrescine accumulation, and thus increase fruit chilling tolerance. In conclusion, our results suggest that the PbrWRKY62-PbrADC1 module is involved in the development of superficial scald in P. bretschneideri Rehd. fruit via regulating putrescine biosynthesis. Consequently, these findings could serve as valuable genetic resources for breeding scald-resistant pear fruit.
PubMed: 38373989
DOI: 10.1186/s43897-024-00081-8 -
Advanced Science (Weinheim,... Apr 2024An ideal hydrogel for stem cell therapy would be injectable and efficiently promote stem cell proliferation and differentiation in body. Herein, an injectable,...
An ideal hydrogel for stem cell therapy would be injectable and efficiently promote stem cell proliferation and differentiation in body. Herein, an injectable, single-component hydrogel with hyaluronic acid (HA) modified with phenylboronic acid (PBA) and spermidine (SM) is introduced. The resulting HAps (HA-PBA-SM) hydrogel is based on the reversible crosslinking between the diol and the ionized PBA, which is stabilized by the SM. It has a shear-thinning property, enabling its injection through a syringe to form a stable hydrogel inside the body. In addition, HAps hydrogel undergoes a post-injection "self-curing," which stiffens the hydrogel over time. This property allows the HAps hydrogel to meet the physical requirements for stem cell therapy in rigid tissues, such as bone, while maintaining injectability. The hydrogel enabled favorable proliferation of human mesenchymal stem cells (hMSCs) and promoted their differentiation and mineralization. After the injection of hMSCs-containing HAps into a rat femoral defect model, efficient osteogenic differentiation of hMSCs and bone regeneration is observed. The study demonstrates that simple cationic modification of PBA-based hydrogel enabled efficient gelation with shear-thinning and self-curing properties, and it would be highly useful for stem cell therapy and in vivo bone regeneration.
Topics: Animals; Bone Regeneration; Rats; Hydrogels; Mesenchymal Stem Cells; Humans; Cell Differentiation; Hyaluronic Acid; Rats, Sprague-Dawley; Cell Encapsulation; Cell Proliferation; Osteogenesis; Disease Models, Animal; Spermidine; Boronic Acids
PubMed: 38355304
DOI: 10.1002/advs.202304861 -
Biochemistry Research International 2024Bacterial and mammalian cells are rich in putrescine, spermidine, and spermine. Polyamines are required for optimum fitness, but the biological function of these small...
Bacterial and mammalian cells are rich in putrescine, spermidine, and spermine. Polyamines are required for optimum fitness, but the biological function of these small aliphatic compounds has only been partially revealed. Known functions of polyamines include interaction with nucleic acids that alters gene expression and with proteins that modulate activity. Although polyamines can be incorporated into proteins, very few naturally occurring polyaminated proteins have been identified, which is due in part to the difficulty in detecting these adducts. In the current study, bovine albumin and the recombinant universal stress protein from were used as models for mass spectrometry analysis of polyaminated proteins. The proteins were covalently bound to putrescine, spermidine, or spermine by the action of carbodiimide or microbial transglutaminase. Tryptic peptides, subjected to liquid chromatography tandem mass spectrometry (LC-MS/MS), were identified using Protein Prospector software. We describe the search parameters for identifying polyaminated peptides and show MS/MS spectra for adducts with putrescine, spermidine, and spermine. Manual evaluation led us to recognize signature ions for polyamine adducts on aspartate, glutamate, and glutamine, as well as neutral loss from putrescine, spermidine, and spermine during the fragmentation process. Mechanisms for the formation of signature ions and neutral loss are presented. Manual evaluation identified a false-positive adduct that had formed during trypsinolysis and resulted in peptide sequence rearrangement. Another false positive initially appeared to be a 71 kDa putrescine adduct on a cysteine residue. However, it was an acrylamide adduct on cysteine for a sample extracted from a polyacrylamide gel. The information presented in this report provides guidance and serves as a model for identifying naturally occurring polyaminated proteins.
PubMed: 38347948
DOI: 10.1155/2024/7120208 -
Journal of Agricultural and Food... Feb 2024Biogenic amines (BAs) are biologically active nitrogen-containing compounds formed during the food spoilage process and are often related as key markers of food quality,...
Biogenic amines (BAs) are biologically active nitrogen-containing compounds formed during the food spoilage process and are often related as key markers of food quality, safety, and freshness. Because their presence in foods at high levels can cause significant health problems, researchers have been focused on developing novel strategies and methods for early detection and capture of these analytes. Herein, water-soluble sulfonated calix[]arene macrocycles (SC4, SC6, and SC8) and a pH-sensitive dye (4'-hydroxy-10-methylpyranoflavylium) were investigated as host-guest systems for BA sensing. The hosts were able to bind the flavylium cation of the dye with association constants of 10 to 10 M. The dye complexation also allowed tuning its p from 6.72 (free) toward high values: 7.68 (SC4), 7.79 (SC6), and 8.45 (SC8). These data were crucial to optimize the host-guest complexes as optical sensing systems for putrescine/tyramine (pH 7.2-7.6), yielding a colorimetric redshift from yellow to red. The BA sensing was also demonstrated by fluorescence quenching for the calix[]arene/dye complexes and fluorescence recovery after the addition of BAs. H NMR spectroscopy was used to demonstrate the interaction mode, confirming an encapsulation-driven mechanism. Overall, these host-guest systems demonstrated great potential for the detection of BAs, one of the main key markers of food spoilage.
Topics: Calixarenes; Water; Putrescine; Biogenic Amines
PubMed: 38345747
DOI: 10.1021/acs.jafc.3c08695