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PloS One 2022The purpose of this study was to investigate the abundance and distribution of psychrophilic microorganisms associated with spoilage in beef slaughterhouse environments...
The purpose of this study was to investigate the abundance and distribution of psychrophilic microorganisms associated with spoilage in beef slaughterhouse environments after cleaning. The processing lines and equipment used in slaughtering and boning were swabbed, and the microbial count was determined using a TSA and MRS medium and Chromocult® Coliform agar incubated at 15ºC and 37ºC, respectively. As a result, the brisket saw (handle side) and trolley hook were the most heavily contaminated with microorganisms, with each having a microbial adhesion rate of 66.7%. The microbial adhesion rates of the apron and milling cutter (edge side) were 50%, respectively, and those of the foot cutter (edge and handle side), splitting saw (edge side), and knife (handle side) were 33.3%, respectively. Next, four colonies were randomly isolated from the petri dish used for the bacterial count measurement to identify the predominant microbial species of the microorganisms attached to each equipment. As a result of Sanger sequencing analysis, yeasts such as Candida zeylanoides and Rhodotorula sp. and bacteria including Pseudomonas sp. and Rhodococcus sp. were identified from the equipment used in the slaughtering line, and it was assumed that these microorganisms were of environmental origin. In contrast, only Pseudomonas sp. and Candida zeylanoides were isolated from the boning line. Despite the use of cleaning operations, this study identified some equipment was contaminated with microorganisms. Since this equipment frequently comes into direct contact with the carcass, it is critical to thoroughly remove the microorganisms through accurate cleaning to prevent the spread of microbial contamination on the carcasses.
Topics: Abattoirs; Animals; Cattle; Colony Count, Microbial; Food Handling; Food Microbiology; Japan; Meat; Saccharomycetales; Yeasts
PubMed: 35921278
DOI: 10.1371/journal.pone.0268411 -
Frontiers in Physiology 2021Alcohol-associated liver disease (ALD) is an important cause of morbidity and mortality worldwide. The intestinal microbiota is involved in the development and...
BACKGROUND
Alcohol-associated liver disease (ALD) is an important cause of morbidity and mortality worldwide. The intestinal microbiota is involved in the development and progression of ALD; however, little is known about commensal fungi therein.
METHODS
We studied the dynamic changes of the intestinal fungal microbiome, or mycobiome, in 66 patients with alcohol use disorder (AUD) and after 2 weeks of alcohol abstinence using internal transcribed spacer 2 (ITS2) amplicon sequencing of fecal samples.
RESULTS
Patients with AUD had significantly increased abundance of the genera , , , , and , and of the species and compared with control subjects. Significantly improved liver health markers caspase-cleaved and intact cytokeratin 18 (CK18-M65) levels and controlled attenuation parameter (CAP) in AUD patients after 2 weeks of alcohol abstinence were associated with significantly lower abundance of the genera , , , , , and the species and . This was mirrored by significantly higher specific anti- immunoglobulin G (IgG) and M (IgM) serum levels in AUD patients in relation to control participants, and significantly decreased anti- IgG levels in AUD subjects after 2 weeks of abstinence. The intestinal abundance of the genus was significantly higher in AUD subjects with progressive liver disease compared with non-progressive liver disease.
CONCLUSION
In conclusion, improved liver health in AUD patients after alcohol abstinence was associated with lower intestinal abundances of and , and lower serum anti- IgG levels. Intestinal fungi might serve as a therapeutic target to improve the outcome of patients in ALD.
PubMed: 34349667
DOI: 10.3389/fphys.2021.699253 -
Frontiers in Microbiology 2022Sliced cooked ham packaged in a modified atmosphere is a popular ready-to-eat product, subjected to abundant microbial contamination throughout its shelf life that can...
Sliced cooked ham packaged in a modified atmosphere is a popular ready-to-eat product, subjected to abundant microbial contamination throughout its shelf life that can lead to deterioration of both sensorial properties and safety. In this study, the microbial load and the chemical-physical features of cooked ham of five producers were monitored for a period of 12 days after the opening of the packages (i.e., the secondary shelf life), during which the products were stored in a domestic refrigerator at 5.2 ± 0.6°C. The sensorial properties presented a perceivable decay after 8 days and became unacceptable after 12 days. High-performance liquid chromatography analysis and solid-phase microextraction coupled with gas chromatography profiling of volatile metabolites indicated that lactic acid, ethanol, acetic acid, acetoin, 3-methyl-1-butanol, and 2-3 butanediol were the main metabolites that characterized the evolution of the analyzed cooked ham. The microbiota was monitored by 16S ribosomal RNA gene profiling and culture-dependent techniques. Already at the opening of packages, all the products presented high microbial load, generally dominated by lactic acid bacteria, with evident differences among the products. The increase of lactic acid bacteria somehow protected samples from abundant contamination by other bacteria, concurring with the evolution of more safe products. This role was exerted by numerous , , and species, among which the most frequently detected were , , , and Some products presented more complex communities that encompassed Proteobacteria such as , , , and less frequently , , and . Opportunistic pathogenic bacteria such as and V sp. were found in small quantities. The yeasts and occurred already at 0 days, whereas various species of (, , , and ) were abundant only after 12 days. These results indicated that the microbiological contaminants overgrowing during the secondary shelf life did not derive from environmental cross-contamination at the opening of the tray but were already present when the packages were opened, highlighting the phases of production up to the packaging as those crucial in managing the safety risk associated to this product.
PubMed: 35350621
DOI: 10.3389/fmicb.2022.842390 -
Journal of Applied Microbiology Nov 2021The complex mycobiota that colonizes traditional fermented sausages plays an important role in the organoleptic properties of such products. The aim of the present study...
AIMS
The complex mycobiota that colonizes traditional fermented sausages plays an important role in the organoleptic properties of such products. The aim of the present study was to investigate fungal diversity and mycotoxin production during maturation of PGI Salame Piemonte.
METHODS AND RESULTS
Casing and meat samples were collected at five sampling times from three different batches produced in the same factory and analysed using culture-dependent and independent approaches. Penicillium nalgiovense, which was deliberately inoculated, and Debaryomyces hansenii were the most dominant taxa in casings. Several other fungi mainly belonging to Penicillium crustosum, Penicillium glabrum, Penicillium nordicum, Cladosporium spp., Candida sake, Candida zeylanoides and Yarrowia divulgata were also identified. The casing mycobiota was compared to that of the meat using a metataxonomic approach and a higher fungal diversity was observed in meat as compared to casings. Mycotoxins and penicillin G were monitored using QTOF LC-MS and only trace amounts of roquefortine C were detected in two batches.
CONCLUSIONS
The present study highlighted the diversity of Salame Piemonte mycobiota and the important contribution of autochthonous fungi to its diversity. The absence of mycotoxins and penicillin G confirmed the high hygienic quality of the studied product regarding fungal and mycotoxin contamination.
SIGNIFICANCE AND IMPACT OF THE STUDY
For the first time, this study provides insights about Salame Piemonte mycobiota, which together with the bacterial microbiota and Salame Piemonte process specifications, are responsible for the product organoleptic properties.
Topics: Candida; Fermentation; Food Microbiology; Meat Products; Mycotoxins; Penicillium; Saccharomycetales
PubMed: 33893697
DOI: 10.1111/jam.15114 -
Applied and Environmental Microbiology Oct 2000Yeast isolates from raw and processed poultry products were characterized using PCR amplification of the internally transcribed spacer (ITS) 5.8S ribosomal DNA region...
Yeast isolates from raw and processed poultry products were characterized using PCR amplification of the internally transcribed spacer (ITS) 5.8S ribosomal DNA region (ITS-PCR), restriction analysis of amplified products, randomly amplified polymorphic DNA (RAPD) analysis, and pulsed-field gel electrophoresis (PFGE). ITS-PCR resulted in single fragments of 350 and 650 bp, respectively, from eight strains of Yarrowia lipolytica and seven strains of Candida zeylanoides. Digestion of amplicons with HinfI and HaeIII produced two fragments of 200 and 150 bp from Y. lipolytica and three fragments of 350, 150, and 100 bp from C. zeylanoides, respectively. Although these fragments showed species-specific patterns and confirmed species identification, characterization did not enable intraspecies typing. Contour-clamped heterogeneous electric field PFGE separated chromosomal DNA of Y. lipolytica into three to five bands, most larger than 2 Mbp, whereas six to eight bands in the range of 750 to 2,200 bp were obtained from C. zeylanoides. Karyotypes of both yeasts showed different polymorphic patterns among strains. RAPD analysis, using enterobacterial repetitive intergenic sequences as primers, discriminated between strains within the same species. Cluster analysis of patterns formed groups that correlated with the source of isolation. For ITS-PCR, extraction of DNA by boiling yeast cells was successfully used.
Topics: Animals; Candida; Chickens; DNA, Fungal; Meat; Phylogeny; Polymerase Chain Reaction; Random Amplified Polymorphic DNA Technique; Saccharomycetales; Turkeys; Yeasts
PubMed: 11010879
DOI: 10.1128/AEM.66.10.4340-4344.2000 -
Applied and Environmental Microbiology Aug 2008The effects of acidified-nitrite stress on the growth initiation and intracellular pH (pH(i)) of individual cells of Debaryomyces hansenii and Candida zeylanoides were...
The effects of acidified-nitrite stress on the growth initiation and intracellular pH (pH(i)) of individual cells of Debaryomyces hansenii and Candida zeylanoides were investigated. Our results show that 200 microg/ml of nitrite caused pronounced growth inhibition and intracellular acidification of D. hansenii at an external pH (pH(ex)) value of 4.5 but did not at pH(ex) 5.5. These results indicate that nitrous acid as such plays an important role in the antifungal effect of acidified nitrite. Furthermore, both yeast species experienced severe growth inhibition and a pH(i) decrease at pH(ex) 4.5, suggesting that at least some of the antifungal effects of acidified nitrite may be due to intracellular acidification. For C. zeylanoides, this phenomenon could be explained in part by the uncoupling effect of energy generation from growth. Debaryomyces hansenii was more tolerant to acidified nitrite at pH(ex) 5.5 than C. zeylanoides, as determined by the rate of growth initiation. In combination with the fact that D. hansenii was able to maintain pH(i) homeostasis at pH(ex) 5.5 but C. zeylanoides was not, our results suggest that the ability to maintain pH(i) homeostasis plays a role in the acidified-nitrite tolerance of D. hansenii and C. zeylanoides. Possible mechanisms underlying the different abilities of the two yeast species to maintain their pH(i) homeostasis during acidified-nitrite stress, comprising the intracellular buffer capacity and the plasma membrane ATPase activity, were investigated, but none of these mechanisms could explain the difference.
Topics: Adenosine Triphosphatases; Ascomycota; Candida; Cell Membrane; Cell Wall; Drug Tolerance; Fungal Proteins; Hydrogen-Ion Concentration; Nitrites
PubMed: 18539814
DOI: 10.1128/AEM.00571-08 -
Foods (Basel, Switzerland) Jul 2020Traditional fermented bean pastes are indispensable seasonings in many East Asian countries. They are produced via hypertonic solutions by spontaneous fermentation....
Traditional fermented bean pastes are indispensable seasonings in many East Asian countries. They are produced via hypertonic solutions by spontaneous fermentation. Functional, unknown microbiota carry great risks for food safety and stable quality. Thus, analysis and subsequent utilization of functional microbiota will be a good strategy to resolve these problems. During bean fermentation, the microbial functions were divided into two stages, including first stage-raw material (polypeptide) degradation and second stage-amino acid catabolism. In this study, we aimed to analyze the functional microbiota of first stage. Omics-studies, including high-throughput sequencing, correlation analysis and extracellular proteome, were used to generate candidate functional microbes for polypeptide degradation in this study. Then, we cultured the candidate functional microbes. After the batch fermentation and enzymatic analysis, we found three strains secreted peptidase and resulted amino acid accumulation, involving , and . Thus, , and conducted the functional microbiota for polypeptide degrading during hypertonic moromi fermentation. This study supplies a strategy for functional microbiota analysis. In addition, this is the first report that can secrete proteome and produce amino acids from polypeptide.
PubMed: 32674449
DOI: 10.3390/foods9070930 -
Food Research International (Ottawa,... Apr 2024Meat dry aging consists in storing unpackaged meat in a cold room, and at a specific and controlled relative humidity (RH), for a period of 1 to 5 weeks or more. This...
Meat dry aging consists in storing unpackaged meat in a cold room, and at a specific and controlled relative humidity (RH), for a period of 1 to 5 weeks or more. This practice has become widespread in recent years due to its positive effect on the tenderness of the meat but also on other organoleptic characteristics and therefore its market value. The objective of this work was to study the bacterial and fungal microbiota of dry-aged beef at the commercial stage by both culture-dependent and -independent approaches. Fifty-eight samples of dry-aged meat from different producer types (meat processing plants, artisanal and supermarket butchers) were studied. The dry-aging conditions (temperature, RH) of the meats, as well as the surface pH and a, were measured. The main microbial groups were enumerated by culture on various dedicated media. Concerning fungi, isolates of yeasts and molds (n = 257) were identified after dereplication by FTIR spectroscopy and/or sequencing of taxonomically relevant genes (26S rDNA, ITS, β-tubulin, actin). Metagenetic analyzes targeting the V3-V4 regions of 16S rDNA and ITS2 were also performed. Overall, ripening practices were diversified with temperatures and RH between 0.5 and 2.8 °C (median = 2 °C) and 47 and 88 % (median = 70 %), respectively. The aerobic colony count varied between 1.97 and 10.91 log CFU/g (median = 8.32 log CFU/g) and was similar to that of Pseudomonas spp., indicating that this bacterial group was dominant. Yeast populations varied between <2 and 9.41 log CFU/g, while molds showed abundances between <2 and 7.7 log TFU/g, the highest values being found in meats matured with a high RH. Bacterial and mold counts were positively correlated with the dry-aging RH and, to a lesser extent, temperature. The main yeast species were Candida zeylanoides and Yarrowia alimentaria as well as Itersonilia pannonica (identified only in metagenetics). The dominant mold species were psychrophilic or psychrotrophic species, namely Mucor complex flavus and Helycostylum elegans/pulchrum that have already been shown to be associated with dry-aged beef meat. This study has identified the main microorganisms associated with dry-aged meat in France, which raises the question of their role in the organoleptic quality of these higher value products.
Topics: Animals; Cattle; Microbiota; Mycobiome; France; DNA, Ribosomal; Mucor
PubMed: 38448091
DOI: 10.1016/j.foodres.2024.114118 -
Journal of Clinical Microbiology Aug 1991A patient with a long history of scleroderma and gastrointestinal malabsorption requiring total parenteral nutrition was admitted with Candida zeylanoides fungemia. The...
A patient with a long history of scleroderma and gastrointestinal malabsorption requiring total parenteral nutrition was admitted with Candida zeylanoides fungemia. The yeast responded to therapy, but on two subsequent admissions for episodes of fever the blood cultures yielded the same yeast. The identity of the Candida species was established biochemically by both the API (Analytab) and Vitek system approaches. C. zeylanoides ATCC 20356 and ATCC 7351 served as controls for these analyses and for antifungal susceptibility studies and restriction endonuclease analyses of chromosomal DNA. These investigations indicated that representative isolates of the yeasts from the three episodes were identical and differed in several respects from the ATCC strains, which did not share many of the characteristics bands with the DNA restriction fragment analysis. C. zeylanoides variants capable of tolerating 35 degrees C can complicate the recovery of patients, especially individuals compromised by their underlying disease.
Topics: Amphotericin B; Candida; Catheterization, Central Venous; DNA, Fungal; Drug Resistance, Microbial; Electrophoresis, Polyacrylamide Gel; Female; Fluconazole; Flucytosine; Humans; Ketoconazole; Microbial Sensitivity Tests; Middle Aged; Parenteral Nutrition, Total; Polymorphism, Restriction Fragment Length
PubMed: 1684799
DOI: 10.1128/jcm.29.8.1689-1692.1991 -
The Canadian Journal of Infectious... 2017Peritonitis and exit-site infections are important complications in peritoneal dialysis (PD) patients that are occasionally caused by opportunistic fungi inhabiting...
Peritonitis and exit-site infections are important complications in peritoneal dialysis (PD) patients that are occasionally caused by opportunistic fungi inhabiting distant body sites. In this study, the oral yeast colonization of PD patients and the antifungal susceptibility profile of the isolated yeasts were accessed and correlated with fungal infection episodes in the following 4 years. Saliva yeast colonization was accessed in 21 PD patients and 27 healthy controls by growth in CHROMagar-Candida® and 18S rRNA/ITS sequencing. PD patients presented a lower oral yeast prevalence when compared to controls, namely, . Other species were also isolated, and . The antifungal susceptibility profiles of these isolates revealed resistance to itraconazole, variable susceptibility to caspofungin, and higher MIC values of posaconazole compared to previous reports. The 4-year longitudinal evaluation of these patients revealed and as PD-related exit-site infectious agents, but no correlation was found with oral yeast colonization. This pilot study suggests that oral yeast colonization may represent a limited risk for fungal infection development in PD patients. Oral yeast isolates presented a variable antifungal susceptibility profile, which may suggest resistance to some second-line drugs, highlighting the importance of antifungal susceptibility assessment in the clinical practice.
PubMed: 29430252
DOI: 10.1155/2017/4846363