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Life (Basel, Switzerland) Jul 2021Knowledge of the composition of the gut microbiota in freshwater fish living in their natural habitat has taxonomic and ecological importance. Few reports have been...
Knowledge of the composition of the gut microbiota in freshwater fish living in their natural habitat has taxonomic and ecological importance. Few reports have been produced on the composition of the gut microbiota and on the presence of LAB in the intestines of freshwater fish that inhabit river environments. In this study, we investigated the LAB community that was present in the gastrointestinal tract (GIT) of Mediterranean trout () that colonized the Biferno and Volturno rivers of the Molise region (Italy). The partial 16S rRNA gene sequences of these strains were determined for the species-level taxonomic placement. The phylogenetic analysis revealed that the isolated LABs belonged to seven genera ( and ). The study of the enzymatic activities showed that these LABs could contribute to the breakdown of polysaccharides, proteins, and lipids. In future studies, a greater understanding of how the LABs act against pathogens and trigger the fish immune response may provide practical means to engineer the indigenous fish microbiome and enhance disease control and fish health.
PubMed: 34357039
DOI: 10.3390/life11070667 -
Microbiology Spectrum Apr 2024Given the burgeoning Nyctereutes procyonoides breeding industry and its growing scale, it is imperative to investigate the impact of high-fat diets on the health of...
Given the burgeoning Nyctereutes procyonoides breeding industry and its growing scale, it is imperative to investigate the impact of high-fat diets on the health of these animals. This study involved 30 male Nyctereutes procyonoides of comparable weights (3 kg ±0.5), randomly assigned to either a control group or a high-fat diet group ( = 15 each). The latter group was fed a mixture of lard and basal diet in a 2:5 ratio, establishing a high-fat diet model in Nyctereutes procyonoides. This diet induced diarrhea and histopathological changes in the Nyctereutes procyonoides. Analysis of the small intestine contents using 16S rRNA sequencing revealed a high-fat diet-induced disruption in the gut microbiota. Specifically, emerged as the biomarker in the high-fat diet group ( = 0.049), while was prevalent in the control group ( = 0.049), indicating a significant increase in harmful bacteria in the high-fat diet group. Furthermore, this disrupted gut flora correlated with inflammation and oxidative stress, as evidenced by marked increases in TNF-α ( < 0.01), IL-1β ( < 0.05), and IL-6 ( < 0.05) levels, measured q-PCR, Western blot, and oxidative stress assays. In addition, q-PCR analysis revealed significant upregulation of apoptosis and necrosis markers, including Bax, Caspase3, Caspase9, Caspase12, RIPK3, and RIPK1 ( < 0.01 to < 0.001), and a concurrent downregulation of the anti-apoptotic gene Bcl-2 ( < 0.01) in the high-fat diet group, consistent with protein expression trends. These findings suggest that a high-fat diet alters the gut microbiome toward a more harmful bacterial composition, escalating inflammatory responses and intestinal tissue permeability, culminating in intestinal cell apoptosis and necrosis.IMPORTANCEThis study examines the impact of high-fat diets on Nyctereutes procyonoides. Our research established a Nyctereutes procyonoides model on a high-fat diet, revealing significant health impacts, such as diarrhea, histological anomalies, and alterations in the gut microbiota. These findings emphasize the importance of preventing health issues and promoting sustainable industry growth. They highlight the significant impact of diet on gut microbiota and overall animal health.
Topics: Animals; Male; Apoptosis; Bacteria; Diarrhea; Diet, High-Fat; Gastrointestinal Microbiome; Inflammation; Intestines; Necrosis; Raccoon Dogs; RNA, Ribosomal, 16S; Tight Junctions
PubMed: 38376358
DOI: 10.1128/spectrum.04182-23 -
PeerJ 2023Sodium hypochlorite is generally used as a disinfectant in washing of freshwater fishes where the safety aspect of health is of concern. Although plant-based essential...
Sodium hypochlorite is generally used as a disinfectant in washing of freshwater fishes where the safety aspect of health is of concern. Although plant-based essential oils and synthetic chemical agents have been applied, they might contain toxic substances, are expensive and can cause undesirable quality. This research aims to fill the knowledge gap necessary to validate juice as a disinfecting agent for preserving striped catfish steaks at -20 °C for 28 days. Fifty (50) ppm sodium hypochlorite was used as a commercial disinfectant (control). The results showed that a negative color characteristic (higher a* and increased b*) was found in the control but not in striped catfish steaks immersed in juice (TM) on days 14 and 28. No significant differences were found in the peroxide value among the treatments on days 14 and 28 ( > 0.05). A lower accumulation of trichloroacetic acid soluble peptides was detected in TM but not in control, while total volatile basic nitrogen of all treatments was up to standard of fish quality during storage. Contrastingly, the total viable count of both treatments increased to >7.0 log CFU/g on day 28 which did not meet the edible limit of standard for freshwater fishes. The spoilage microbial community was observed on days 0 and 28 of storage which showed a decrease in relative abundance of , and as found in TM on day 28, when compared to the control. Thus, these results implied that juice could replace sodium hypochlorite as an alternative disinfecting agent to control the microbiological spoilage and physico-chemical quality of striped catfish steaks.
Topics: Animals; Sodium Hypochlorite; Catfishes; Disinfectants; Plant Oils; Citrus
PubMed: 37065691
DOI: 10.7717/peerj.15168 -
Journal of Chromatography. A Aug 2024Decomposition odor is produced during postmortem mammalian tissue breakdown by bacteria, insects, and intrinsic chemical processes. Past research has not thoroughly...
Decomposition odor is produced during postmortem mammalian tissue breakdown by bacteria, insects, and intrinsic chemical processes. Past research has not thoroughly investigated which volatile organic compounds (VOCs) can be linked directly to individual bacterial species on decomposing remains. The purpose of this study was to profile the VOCs produced over time by individual species of bacteria using comprehensive two-dimensional gas chromatography (GC×GC) to expand our foundational knowledge of what each bacterial species contributes to decomposition odor. Five different species of bacteria (Bacillus subtilis, Ignatzschineria indica, Ignatzschineria ureiclastica, Curtobacterium luteum, and Vagococcus lutrae) were cultured on standard nutrient agar individually and monitored daily using solid phase microextraction arrow (SPME Arrow) and GC×GC in combination with quadrupole mass spectrometry (qMS) and flame ionization detection (FID). The GC×GC-qMS/FID approach was used to generate rich VOC profiles that represented the bacterial species' metabolic VOC production longitudinally. The data obtained from the chromatographic output was used to compare with a prior study using one-dimensional GC-qMS, and also between each of the five species to investigate the extent of overlap between species. No single VOC could be found in all five bacterial species investigated, and there was little overlap in the profile between species. To further visualize these differences, chromatographic peak data was investigated using two different ordination strategies, principal component analysis (PCA) and principal coordinate analysis (PCoA). The two ordination strategies were compared with each other using a Procrustes analysis. This was performed to understand differences in ordination strategies between the separation science community and chemical ecological community. Overall, ordination strategies were found to produce similar results, as evidenced by the correlation of PCA and PCoA in the Procrustes analysis. All analysis strategies yielded distinct VOC profiles for each species. Further study of additional species will support understanding of the holistic view of decomposition odor from a chemical ecology perspective, and further support our understanding of the production of decomposition odor that culminates from such a complex environment.
Topics: Volatile Organic Compounds; Bacteria; Solid Phase Microextraction; Gas Chromatography-Mass Spectrometry; Animals; Odorants; Postmortem Changes; Chromatography, Gas
PubMed: 38797136
DOI: 10.1016/j.chroma.2024.465017 -
Molecules (Basel, Switzerland) Feb 2024The blue crab (BC) is considered an invasive species colonizing Tunisian coasts since 2014. This work aims to explore its associated bacteria potential to produce...
The blue crab (BC) is considered an invasive species colonizing Tunisian coasts since 2014. This work aims to explore its associated bacteria potential to produce anionic exopolysaccharides (EPSs) in order to open up new ways of valorization. In this study, different BC samples were collected from the coastal area of Sfax, Tunisia. First, bacterial DNA was extracted from seven different fractions (flesh, gills, viscera, carapace scraping water, and three wastewaters from the production plant) and then sequenced using the metabarcoding approach targeting the V3-V4 region of the 16S rDNA to describe their microbiota composition. Metabarcoding data showed that the dominant bacterial genera were mainly , , and . In parallel, plate counting assays were performed on different culture media, and about 250 bacterial strains were isolated and identified by sequencing the 16S rDNA. EPS production by this new bacterial diversity was assessed to identify new compounds of biotechnological interest. The identification of the bacterial strains in the collection confirmed the dominance of spp. strains. Among them, 43 were identified as EPS producers, as revealed by Stains-all dye in agarose gel electrophoresis. A strain produced an EPS rich in both neutral sugars including rare sugars such as rhamnose and fucose and uronic acids. This original composition allows us to assume its potential for biotechnological applications and, more particularly, for developing innovative therapeutics. This study highlights bacterial strains associated with BC; they are a new untapped source for discovering innovative bioactive compounds for health and cosmetic applications, such as anionic EPS.
Topics: Animals; Brachyura; Bacteria; Microbiota; Sugars; DNA, Ribosomal; Polysaccharides, Bacterial
PubMed: 38398526
DOI: 10.3390/molecules29040774 -
Journal of Food Science and Technology Dec 2019Dairy foods are complex ecosystems composed of microorganisms from different origins that can affect flavor and safety of final products. The objective of this paper is...
Dairy foods are complex ecosystems composed of microorganisms from different origins that can affect flavor and safety of final products. The objective of this paper is to assess the in-house microbiota of two Brazilian dairies and to discuss the possible implications of the taxa determined for food protection. In total, 27 samples from dairies were cultured in selective (Baird Parker, de Man, Rogosa and Sharpe) and non-selective (Brain Heart Infusion) media, and the isolates were identified by Sanger sequencing. Moreover, metagenomic DNA was directly extracted from samples and the structure of the bacterial community was determined by massive DNA sequencing followed by bioinformatics analyses. The results showed the majority of isolates belonged to the group of lactic acid bacteria, but , , , and were also detected. From the reads obtained in metataxonomics analyses, a heatmap was constructed and the top 20 OTUs (operational taxonomic units) were determined. Besides, 12 most prevalent bacterial taxa were assigned to the core microbiota of the dairies evaluated, which included , , , , , , , , , , and . In conclusion, the results reveal the presence of bacteria that may be related to spoilage and also foodborne diseases, in microbial niches that also present rare taxa, highlighting the importance to consider culture-independent results to evaluate and improve food safety.
PubMed: 31749480
DOI: 10.1007/s13197-019-04003-1 -
PloS One 2024The field of fish microbiome research has rapidly been advancing, primarily focusing on farmed or laboratory fish species rather than natural or marine fish populations....
The field of fish microbiome research has rapidly been advancing, primarily focusing on farmed or laboratory fish species rather than natural or marine fish populations. This study sought to reveal the distinctive gut bacteriome composition and diversity within the anadromous fish species Tenualosa ilisha (hilsa), which holds the status of being the national fish of Bangladesh. We conducted an analysis on 15 gut samples obtained from 15 individual hilsa fishes collected from three primary habitats (e.g., freshwater = 5, brackish water = 5 and marine water = 5) in Bangladesh. The analysis utilized metagenomics based on 16S rRNA gene sequencing targeting the V3-V4 regions. Our comprehensive identification revealed a total of 258 operational taxonomic units (OTUs). The observed OTUs were represented by six phyla, nine classes, 19 orders, 26 families and 40 genera of bacteria. Our analysis unveiled considerable taxonomic differences among the habitats (freshwater, brackish water, and marine water) of hilsa fishes, as denoted by a higher level of shared microbiota (p = 0.007, Kruskal-Wallis test). Among the identified genera in the gut of hilsa fishes, including Vagococcus, Morganella, Enterobacter, Plesiomonas, Shigella, Clostridium, Klebsiella, Serratia, Aeromonas, Macrococcus, Staphylococcus, Proteus, and Hafnia, several are recognized as fish probiotics. Importantly, some bacterial genera such as Sinobaca, Synechococcus, Gemmata, Serinicoccus, Saccharopolyspora, and Paulinella identified in the gut of hilsa identified in this study have not been reported in any aquatic or marine fish species. Significantly, we observed that 67.50% (27/40) of bacterial genera were found to be common among hilsa fishes across all three habitats. Our findings offer compelling evidence for the presence of both exclusive and communal bacteriomes within the gut of hilsa fishes, exhibiting potential probiotic properties. These observations could be crucial for guiding future microbiome investigations in this economically significant fish species.
Topics: Animals; Bangladesh; Gastrointestinal Microbiome; Fishes; RNA, Ribosomal, 16S; Bacteria; Biodiversity; Phylogeny
PubMed: 38691556
DOI: 10.1371/journal.pone.0303047 -
Animals : An Open Access Journal From... Jan 2024This research investigates the potential of lactic acid bacteria (LAB) from freshwater salmonids as prospective probiotics for application in aquaculture. LAB and...
This research investigates the potential of lactic acid bacteria (LAB) from freshwater salmonids as prospective probiotics for application in aquaculture. LAB and pathogenic bacteria were obtained from mucus and tissues of and from fish farms in northeast Spain that had not used antibiotics for the six months preceding the study. Isolates were identified using Gram staining and sequencing of 16S rRNA and ITS-1. To assess the safety of the LAB, antibiotic susceptibility tests (ASTs) against 23 antimicrobials were performed. antagonism assays were conducted to evaluate the inhibitory effects of living LAB using the agar diffusion test method and their metabolites using the agar well diffusion method. The assays targeted six specific pathogens: subsp. , and the marine pathogen Additionally, a toxicity assay was conducted on embryonic eggs of . The ASTs on probiotic LAB candidates revealed varied responses to antimicrobials, but no resistance to oxytetracycline or florfenicol, which are two antibiotics commonly used in aquaculture, was detected. The assays indicate that LAB exhibit antagonistic effects against pathogens, primarily when directly stimulated by their presence. In applications involving embryonic eggs or larvae, certain live strains of LAB were found to have adverse effects, with some isolates resulting in higher mortality rates compared to the control group or other isolates. Furthermore, the potential pathogenicity of certain LAB strains, typically considered safe in salmonids, warrants deeper investigation.
PubMed: 38254369
DOI: 10.3390/ani14020200