-
MSystems Dec 2023This study sheds light on that treatment with but not is entitled to protect against necrotizing enterocolitis (NEC) development potentially. The mechanisms behind the...
This study sheds light on that treatment with but not is entitled to protect against necrotizing enterocolitis (NEC) development potentially. The mechanisms behind the opposite effect on NEC may result in different modulation on the level of , which is deeply associated with intestinal homoeostasis. Briefly, through improving the abundance of to alleviate intestinal inflammation and enhance intestinal barrier integrity, supplement may become a promising therapy for NEC.
Topics: Female; Infant, Newborn; Humans; Probiotics; Clostridium butyricum; Clostridium tyrobutyricum; Enterocolitis, Necrotizing; Intestines; Infant, Newborn, Diseases; Fetal Diseases
PubMed: 37921463
DOI: 10.1128/msystems.00732-23 -
Nutrients Feb 2024Obesity and its complications constitute a main threat to global human health. The purpose of this investigation was to explore the influences of (Ct) on lipid...
Obesity and its complications constitute a main threat to global human health. The purpose of this investigation was to explore the influences of (Ct) on lipid metabolism, intestinal barrier function, and intestinal microbiome in obese mice induced by a high-fat diet (HFD). After establishing the obesity model, 10 CFU/mL and 10 CFU/mL were used to intervene in HFD-fed mice by gavage for six weeks, and indexes related to obesity were measured. In the liver of HFD-fed mice, the results revealed that reduced liver weight and the levels of triglyceride (TG), total cholesterol (TC), and nonesterified fatty acid (NEFA), along with decreasing red lipid droplets and fat vacuoles. After intervention, the mRNA expression of peroxisome proliferator-activated receptor-γ (PPARγ) was downregulated, and AMP-activated protein kinase (AMPK), peroxisome proliferator-activated receptor-α (PPARα), adipose triglyceride lipase (ATGL), and hormone-sensitive lipase (HSL) were upregulated in the liver. Additionally, alleviated intestinal morphology injury caused by HFD, decreased the expression of tumor necrosis factor-α (TNF-α), interleukin 6 (IL-6), and IL-1β in the colon, and upregulated tight junction protein expression. In addition, 16S rRNA sequencing revealed that increases the diversity of intestinal microbiota. Overall, improved HFD-induced lipid metabolism disorders, preserved the intestinal barrier's integrity, and modulated the structure of the intestinal microbiome. These findings provide a novel insight into the role of as a probiotic in regulating lipid metabolism.
Topics: Humans; Animals; Mice; Diet, High-Fat; Lipid Metabolism; Gastrointestinal Microbiome; Mice, Obese; Clostridium tyrobutyricum; Intestinal Barrier Function; RNA, Ribosomal, 16S; Peroxisome Proliferator-Activated Receptors; Liver; Obesity; Mice, Inbred C57BL
PubMed: 38398817
DOI: 10.3390/nu16040493 -
Foods (Basel, Switzerland) Mar 2024Microbial conversion of agri-food waste to valuable compounds offers a sustainable route to develop the bioeconomy and contribute to sustainable biorefinery. displays a...
Microbial conversion of agri-food waste to valuable compounds offers a sustainable route to develop the bioeconomy and contribute to sustainable biorefinery. displays a series of native traits suitable for high productivity conversion of agri-food waste, which make it a promising host for the production of various compounds, such as the short-chain fatty acids and their derivative esters products. In this study, a butanol synthetic pathway was constructed in , and then efficient butyl butyrate production through in situ esterification was achieved by the supplementation of lipase into the fermentation. The butyryl-CoA/acyl-CoA transferase () was overexpressed to balance the ratio between precursors butyrate and butanol. Then, a suitable fermentation medium for butyl butyrate production was obtained with xylose as the sole carbon source and shrimp shell waste as the sole nitrogen source. Ultimately, 5.9 g/L of butyl butyrate with a selectivity of 100%, and a productivity of 0.03 g/L·h was achieved under xylose and shrimp shell waste with batch fermentation in a 5 L bioreactor. Transcriptome analyses exhibited an increase in the expression of genes related to the xylose metabolism, nitrogen metabolism, and amino acid metabolism and transport, which reveal the mechanism for the synergistic utilization of xylose and shrimp shell waste. This study presents a novel approach for utilizing xylose and shrimp shell waste to produce butyl butyrate by using an anaerobic fermentative platform based on . This innovative fermentation medium could save the cost of nitrogen sources (~97%) and open up possibilities for converting agri-food waste into other high-value products.
PubMed: 38611315
DOI: 10.3390/foods13071009 -
Food Microbiology Feb 2024Bacteriophages and their endolysins are potential biocontrol agents for the anaerobic spoilage organism Clostridium tyrobutyricum, which causes cheese late blowing...
Bacteriophages and their endolysins are potential biocontrol agents for the anaerobic spoilage organism Clostridium tyrobutyricum, which causes cheese late blowing defect. This study sequenced and compared the genomes of eight bacteriophages from Spanish dairy farms that were active against C. tyrobutyricum, to identify novel species and phage proteins. Phages vB_CtyS-FA67 and vB_CtyS-FA70 shared >94% intergenomic similarity to each other but neither phage had significant similarity to ΦCTP1, the unique C. tyrobutyricum phage sequenced to date. Taxonomic analysis indicated that both phages belong to the class Caudoviricetes and are related to dsDNA viruses with long non-contractile tails. vB_CtyS-FA67 had no other close relatives and encoded a novel endolysin, LysFA67, predicted to belong to the glycoside hydrolase GH24 family. LysFA67 lysed 93% of C. tyrobutyricum cells after 4 min in turbidity reduction assays, retaining lytic activity at pHs 4.2-8.1 and at 30-45 °C. The endolysin remained stable after 30 d storage at 4, 12 and 25 °C, while its activity decreased at -20 °C. LysFA67 lysed several clostridia species, while common dairy bacteria were not affected. Lactococcus lactis INIA 437, used as a cheese starter, was engineered to deliver LysFA67 and red fluorescent LysFA67-mCherry to dairy products. We demonstrated that these engineered strains were able to maintain lytic activity and fluorescence without affecting their technological properties in milk.
Topics: Clostridium tyrobutyricum; Cheese; Clostridium; Endopeptidases; Bacteriophages
PubMed: 37919009
DOI: 10.1016/j.fm.2023.104401 -
International Microbiology : the... Aug 2023Climate change and environmental issues compel us to find alternatives to the production of molecules of interest from petrochemistry. This study aims at understanding...
Climate change and environmental issues compel us to find alternatives to the production of molecules of interest from petrochemistry. This study aims at understanding the production of butyrate, hydrogen, and CO from the oxidation of lactate with acetate in Clostridium tyrobutyricum and thus proposes an alternative carbon source to glucose. This specie is known to produce more butyrate than the other butyrate-producing clostridia species due to a lack of solvent genesis phase. The recent discoveries on flavin-based electron bifurcation and confurcation mechanism as a mode of energy conservation led us to suggest a new metabolic scheme for the formation of butyrate from lactate-acetate co-metabolism. While searching for genes encoding for EtfAB complexes and neighboring genes in the genome of C. tyrobutyricum, we identified a cluster of genes involved in butyrate formation and another cluster involved in lactate oxidation homologous to Acetobacterium woodii. A phylogenetic approach encompassing other butyrate-producing and/or lactate-oxidizing species based on EtfAB complexes confirmed these results. A metabolic scheme on the production of butyrate, hydrogen, and CO from the lactate-acetate co-metabolism in C. tyrobutyricum was constructed and then confirmed with data of steady-state continuous culture. This in silico metabolic carbon flux analysis model showed the coherence of the scheme from the carbon recovery, the cofactor ratio, and the ATP yield. This study improves our understanding of the lactate oxidation metabolic pathways and the role of acetate and intracellular redox balance, and paves the way for the production of molecules of interest as butyrate and hydrogen with C. tyrobutyricum.
Topics: Fermentation; Clostridium tyrobutyricum; Metabolic Flux Analysis; Carbon Dioxide; Phylogeny; Butyrates; Acetates; Lactates; Hydrogen; Computational Biology; Carbon
PubMed: 36609955
DOI: 10.1007/s10123-022-00316-y -
Frontiers in Microbiology 2024The genus is a large and diverse group of species that can cause food spoilage, including late blowing defect (LBD) in cheese. In this study, we investigated the...
The genus is a large and diverse group of species that can cause food spoilage, including late blowing defect (LBD) in cheese. In this study, we investigated the taxonomic status of strain FAM25158 isolated from Emmental cheese with LBD using a polyphasic taxonomic and comparative genomic approach. A 16S rRNA gene sequence phylogeny suggested affiliation to the cluster, with DSM 2637 being the closest related type strain (99.16% sequence similarity). Average Nucleotide Identity (ANI) analysis revealed that strain FAM25158 is at the species threshold with , with ANI values ranging from 94.70 to 95.26%, while the digital DNA-DNA hybridization values were below the recommended threshold, suggesting that FAM25158 is significantly different from at the genomic level. Moreover, comparative genomic analysis between FAM25158 and its four closest relatives revealed a diversity of metabolic pathways, with FAM25158 differing from other strains by the presence of genes such as , , and , responsible for sucrose utilization, and the absence of many important functional genes associated with cold and osmolality adaptation, which was further supported by phenotypic analyses. Surprisingly, strain FAM25158 exhibited unique physiologic traits, such as an optimal growth temperature of 30°C, in contrast to its closest relatives, species with an optimal growth temperature of 37°C. Additionally, the growth of FAM25158 was inhibited at NaCl concentrations higher than 0.5%, a remarkable observation considering its origin from cheese. While the results of this study provide novel information on the genetic content of strain FAM25158, the relationship between its genetic content and the observed phenotype remains a topic requiring further investigation.
PubMed: 38414773
DOI: 10.3389/fmicb.2024.1353321 -
International Journal of Food... Oct 2023Anaerobic spore-forming bacteria are a continuous threat to the dairy industry due to their ability to withstand processing conditions, such as those during heat...
Anaerobic spore-forming bacteria are a continuous threat to the dairy industry due to their ability to withstand processing conditions, such as those during heat treatment. These ubiquitous microorganisms have ample opportunity for multiple entry points into the milk chain, creating food quality and safety issues. Certain spore-formers, namely bacilli and clostridia, are more problematic due to their ability to spoil dairy products and pathogenicity. In this study, we investigated how milk treatment and milk powder production influenced the composition and survival of anaerobic spore-formers. Samples were obtained on three different days (replicate blocks) during the production of dairy powders and examined in a culture-dependent manner using the most probable number method coupled with 16S rRNA amplicon sequencing and metagenomic analysis of the enriched samples. Results revealed that the milk separation greatly affected the spore-former presence and composition which were detected along the entire production line from raw material to milk powders. Throughout the various points of the production line, the occurrence of species belonging to the Bacillus cereus sensu lato was higher than that of clostridia. Sequence variants (SVs) belonging to the anaerobic spore-forming genus Clostridium were taxonomically assigned to two SVs groups and were detected in all three replicate blocks. A total of 19 metagenome-assembled genomes were recovered from nine enrichments. Four near-complete and two medium-quality genomes were found in raw milk/milk powder samples and further assigned as Clostridium tyrobutyricum and Clostridium diolis, which may constitute a problem in the finished dairy product. In conclusion, our findings highlight spore-formers' importance on dairy quality and may aid in their intervention and control in the dairy production line.
Topics: Animals; Milk; Powders; Hot Temperature; Spores, Bacterial; RNA, Ribosomal, 16S; Anaerobiosis
PubMed: 37356408
DOI: 10.1016/j.ijfoodmicro.2023.110281 -
Applied and Environmental Microbiology Oct 2023In the food industry, especially dairy, biofilms can be formed by heat-resistant spoilage and pathogenic bacteria from the farm. Such biofilms may persist throughout the...
In the food industry, especially dairy, biofilms can be formed by heat-resistant spoilage and pathogenic bacteria from the farm. Such biofilms may persist throughout the processing chain and contaminate milk and dairy products continuously, increasing equipment cleaning, maintenance costs, and product recalls. Most biofilms are multispecies, yet most studies focus on single-species models. A multispecies model of dairy biofilm was developed under static and dynamic conditions using heat-resistant and isolated from dairies. and were weak producers of biofilm, whereas the other four were moderate to strong producers. Based on cross-streaking on agar, was found to inhibit and . In multispecies biofilm formed on stainless steel in a CDC reactor fed microfiltered milk, the strong biofilm producers were dominant while the weak producers were barely detectable. All biofilm matrices were dispersed easily by proteinase K treatment but were less sensitive to DNase or carbohydrases. Further studies are needed to deepen our understanding of multispecies biofilms and interactions within to develop improved preventive strategies to control the proliferation of spoilage and pathogenic bacteria in dairies and other food processing environments. IMPORTANCE A model of multispecies biofilm was created to study biofilm formation by heat-resistant bacteria in the dairy industry. The biofilm formation potential was evaluated under static conditions. A continuous flow version was then developed to study multispecies biofilm formed on stainless steel in microfiltered milk under dynamic conditions encountered in dairy processing equipment. The study of biofilm composition and bacterial interactions therein will lead to more effective means of suppressing bacterial growth on food processing equipment and contamination of products with spoilage and pathogenic bacteria, which represent considerable economic loss.
Topics: Animals; Hot Temperature; Stainless Steel; Biofilms; Bacteria; Milk
PubMed: 37732743
DOI: 10.1128/aem.00713-23 -
Foods (Basel, Switzerland) Apr 2024Enumeration of endospores of butyric acid-forming clostridia in cheese milk is an essential part of milk quality monitoring for cheese producers to avoid late blowing,...
Enumeration of endospores of butyric acid-forming clostridia in cheese milk is an essential part of milk quality monitoring for cheese producers to avoid late blowing, severe spoilage caused by clostridia during ripening. However, due to the lack of an internationally standardized method, different methods are used and it is important to consider how the choice of method affects the results. This is particularly relevant when clostridial spore counts in milk are considered for quality payments. The aim of this study was to evaluate the specificity of the AMP-6000 method for the enumeration of endospores of cheese spoiling clostridia in milk. First, to assess the prevalence of diversity and to determine potential non-target species, we identified isolates from positive reactions of the AMP-6000 method used to quantify clostridial endospores in raw milk and teat skin samples by MALDI-TOF MS. Based on these results, a strain library was designed to evaluate method inclusivity and exclusivity using pure cultures of target and non-target strains according to ISO 16140-2:2016. Most target strains, as well as all tested and strains were inclusive. However, may be underestimated as only some strains gave positive results. All non-target strains of bacilli and lysinibacilli, but not all paenibacilli, were confirmed to be exclusive. This study provides performance data to better understand the results of microbiological enumeration of butyric acid-forming clostridia in milk and serves as a basis for future methodological considerations and improvements.
PubMed: 38672865
DOI: 10.3390/foods13081192 -
EFSA Journal. European Food Safety... Jan 2024The qualified presumption of safety (QPS) process was developed to provide a safety assessment approach for microorganisms intended for use in food or feed chains. The...
Update of the list of qualified presumption of safety (QPS) recommended microbiological agents intentionally added to food or feed as notified to EFSA 19: Suitability of taxonomic units notified to EFSA until September 2023.
The qualified presumption of safety (QPS) process was developed to provide a safety assessment approach for microorganisms intended for use in food or feed chains. The QPS approach is based on an assessment of published data for each taxonomic unit (TU), with respect to its taxonomic identity, the body of relevant knowledge and safety concerns. Safety concerns identified for a TU are, where possible, confirmed at the species/strain or product level and reflected by 'qualifications'. In the period covered by this Statement, no new information was found that would change the status of previously recommended QPS TUs. Of 71 microorganisms notified to EFSA between April and September 2023 (30 as feed additives, 22 as food enzymes or additives, 7 as novel foods and 12 from plant protection products [PPP]), 61 were not evaluated because: 26 were filamentous fungi, 1 was , 5 were , 1 was a bacteriophage (all excluded from the QPS evaluation) and 28 were TUs that already have a QPS status. The other 10 notifications belonged to 9 TUs which were evaluated for a possible QPS status: and did not get the QPS recommendation due to the limited body of knowledge about their occurrence in the food and/or feed chains and also due to its ability to generate biologically active compounds with antimicrobial activity; and due to safety concerns. is excluded from future QPS evaluations. is recommended for QPS status with the qualification 'for production purposes only'; is recommended for QPS status with the qualification 'absence of genetic determinants for toxigenic activity'; has been added as a synonym of . The Panel clarifies the extension of the QPS status for genetically modified strains.
PubMed: 38213415
DOI: 10.2903/j.efsa.2024.8517