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Food Science & Nutrition Feb 2023The aim of this study was to investigate the sensory indicators, biogenic amine contents, and bacterial community structure and diversity of chilled chicken stored at... (Review)
Review
The aim of this study was to investigate the sensory indicators, biogenic amine contents, and bacterial community structure and diversity of chilled chicken stored at 4°C under aerobic conditions. Bacterial diversity and dominant bacteria were analyzed using high-throughput sequencing technique (HTS). The relationship between biogenic amine contents and microbial community structure was studied. The results showed that contents of putrescine and cadaverine increased significantly with storage time. Proteobacteria was absolutely dominant flora at the phylum level. The predominant spoilage bacteria found in chicken thighs were , , , , and , and the difference with chicken breasts was related to the presence of and absence of . , , and were reported for the first time as an important contributor to the spoilage-related microflora Bacterial diversity and richness indices showed fluctuating and decreasing trend with storage time. The redundancy analysis showed that the relative abundance of , , and was positively related to the contents of putrescine, cadaverine, and tyramine, while and showed positive relationship with putrescine content. Furthermore, positive relationship of and with the contents of cadaverine and tyramine was proposed for the first time. The key findings of this study can provide experimental data for food safety monitoring during refrigerated storage and preservation for poultry meat products.
PubMed: 36789075
DOI: 10.1002/fsn3.3122 -
Frontiers in Microbiology 2022In this study, we identified and characterized a novel chromosomally-encoded class B metallo-β-lactamase (MBL) gene designated in a carbapenem-resistant isolate P34...
In this study, we identified and characterized a novel chromosomally-encoded class B metallo-β-lactamase (MBL) gene designated in a carbapenem-resistant isolate P34 isolated from sewage discharged from an animal farm. Comparative analysis of the deduced amino acid sequence revealed that WUS-1 shares the highest amino acid similarities with the function-characterized MBLs MUS-1 (AAN63647.1; 70.73%) and TUS-1 (AAN63648.1; 70.32%). The recombinant carrying exhibited increased MICs levels against a number of β-lactam antimicrobials such as carbenicillin, ampicillin and imipenem, and β-lactamase inhibitors (clavulanic acid and tazobactam). The metallo-β-lactamase WUS-1 could also hydrolyze these antimicrobials and the hydrolytic activities could be inhibited by EDTA. Genetic context analysis of revealed that no mobile genetic element was found in its surrounding region. The plasmid pMA84474 of P34 harbored 6 resistance genes ( , , , , and ) within an approximately 17 kb multidrug resistance (MDR) region. These genes, however, were all related to mobile genetic elements.
PubMed: 36532482
DOI: 10.3389/fmicb.2022.1059997 -
Plants (Basel, Switzerland) Nov 2022The aim of our research was to study the endosphere of four halophytic plants: L., (R.Br.), (Pall.) and (L.) Schrad. from arid and saline areas of the Stavropol...
The aim of our research was to study the endosphere of four halophytic plants: L., (R.Br.), (Pall.) and (L.) Schrad. from arid and saline areas of the Stavropol Territory, Russia. In total, 28 endophyte strains were isolated from the roots and stems of these halophytic plants. Most of the isolates (23 out of 28) were identified as sp. while others belonged to the genera and . Three strains of sp. (Se5R, Se1-1R, and Se1-3S), isolated from the were capable of growth at 55 °C and in 10% of NaCl. Strains Se1-4S, Kp20-2S, and Bs11-2S sp. (isolated from the , and respectively) demonstrated strong plant growth promoting activity: 85-265% over control lettuce plants and a high degree of growth suppression (59.1-81.2%) of pathogenic fungi , and . Selected strains can be promising candidates for the development of bioinoculants to facilitate salt soil phytoremediation and be beneficial for mitigating the salt stress to the plants growing in salt-affected habitats.
PubMed: 36365445
DOI: 10.3390/plants11212992 -
Revista Espanola de Quimioterapia :... Dec 2022
Topics: Humans; Flavobacteriaceae; Urinary Tract Infections
PubMed: 36183239
DOI: 10.37201/req/045.2022 -
Foods (Basel, Switzerland) Aug 2022Storage temperature is considered one of the most important factors that affect the microbial spoilage of fresh meat. Chilling and superchilling are the most popular...
Storage temperature is considered one of the most important factors that affect the microbial spoilage of fresh meat. Chilling and superchilling are the most popular storage techniques on the market, but during transportation, the temperature may reach 10 °C and may even reach room temperature during local retail storage. In the present study, we stored fresh pork meat at different temperatures, -2 °C, 4 °C, 10 °C, and 25 °C. The composition and functional potential of fresh or spoiled meat resident microbes were analyzed based on 16S rRNA gene amplicon sequencing. The microbial composition exhibited high similarity between pork meat stored at -2 °C and 4 °C, with and being the dominant taxa. sp., sp., and sp. were markers for spoiled pork meat stored at 25 °C. Both psychrophilic and mesophilic bacteria were observed to grow under a storage temperature of 10 °C, but the overall composition and functional potential based on Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways were found to be similar to that of meat stored at room temperature. Our results broaden the knowledge of possible microbial changes in pork meat during storage, transportation, or retail.
PubMed: 35954075
DOI: 10.3390/foods11152307 -
Microbial Biotechnology Oct 2022Black soldier fly (BSF) larvae are considered a promising biological reactor to convert organic waste and reduce the impact of zoonotic pathogens on the environment. We...
Black soldier fly (BSF) larvae are considered a promising biological reactor to convert organic waste and reduce the impact of zoonotic pathogens on the environment. We analysed the effects of BSF larvae on Staphylococcus aureus and Salmonella spp. populations in pig manure (PM), which showed that BSF larvae can significantly reduce the counts of the associated S. aureus and Salmonella spp. Then, using a sterile BSF larval system, we validated the function of BSF larval intestinal microbiota in vivo to suppress pathogens, and lastly, we isolated eight bacterial strains from the BSF larval gut that inhibit S. aureus. Results indicated that functional microbes are essential for BSF larvae to antagonise S. aureus. Moreover, the analysis results of the relationship between the intestinal microbiota and S. aureus and Salmonella spp. showed that Myroides, Tissierella, Oblitimonas, Paenalcalignes, Terrisporobacter, Clostridium, Fastidiosipila, Pseudomonas, Ignatzschineria, Savagea, Moheibacter and Sphingobacterium were negatively correlated with S. aureus and Salmonella. Overall, these results suggested that the potential ability of BSF larvae to inhibit S. aureus and Salmonella spp. present in PM is accomplished primarily by gut-associated microorganisms.
Topics: Animals; Diptera; Gastrointestinal Microbiome; Larva; Manure; Staphylococcus aureus; Swine
PubMed: 35881487
DOI: 10.1111/1751-7915.14113 -
Case Reports in Infectious Diseases 2022The bacterial genus , like other members of the family, consists of aerobic, non-motile, Gram-negative bacilli. spp. is considered predominantly opportunistic...
The bacterial genus , like other members of the family, consists of aerobic, non-motile, Gram-negative bacilli. spp. is considered predominantly opportunistic pathogens as, historically, most documented infections have been in immunocompromised individuals. Along with advancements in molecular assay testing, there are growing reports of clinically relevant spp. infections in immunocompetent individuals. These organisms display broad antimicrobial resistance, and while research into their mechanisms of resistance is progressing, genetic testing has revealed metallo--lactamases present in their genome. The sporadic identification of spp. and ongoing clarification of resistance patterns make empiric treatment difficult. This report documents two cases of extensively drug-resistant isolated from critically ill but otherwise immunocompetent patients followed by a review of available literature on spp. antibiotic sensitivities. Our findings indicate that minocycline and moxifloxacin have the highest documented activity against spp.
PubMed: 35873406
DOI: 10.1155/2022/6422861 -
Frontiers in Microbiology 2022Bacterial communities in high-temperature Daqu and fermented grains are important for brewing Jiang-flavor Baijiu such as Danquan Baijiu. Daqu is a saccharifying and...
Bacterial communities in high-temperature Daqu and fermented grains are important for brewing Jiang-flavor Baijiu such as Danquan Baijiu. Daqu is a saccharifying and fermenting agent, which has a significant impact on the flavor of Baijiu. However, bacterial communities in three different types of samples from the Danquan distillery (dqjq_ck, dqjqcp, and dqjp3) were still unclear, which limited further development of Danquan Baijiu. "dqjq_ck" and "dqjqcp" indicate high-temperature Daqu at days 45 and 135, respectively. "dqjp3" indicates fermented grains. In this study, the bacterial communities of three samples were analyzed by Illumina Miseq high-throughput sequencing. The bacterial communities of three samples primarily composed of thermophilic bacteria and bacteria with stress resistance. The most abundant species in dqjq_ck, dqjqcp, and dqjp3 were , and , respectively. The main bacteria included , and in three samples (percentage was more than 1% in one of three samples). In our study, the succession of microbiota in three samples representing three important stages of Danquan Baijiu brewing was revealed. This article lays a good foundation for understanding the fermentation mechanism and screening some excellent indigenous bacteria to improve the quality of Danquan Baijiu in future.
PubMed: 35865918
DOI: 10.3389/fmicb.2022.883122 -
Scientific Reports Jul 2022The housefly (Musca domestica) is a wide-ranging insect, often associated with decaying matter from livestock and humans. The septic environments in which houseflies...
The housefly (Musca domestica) is a wide-ranging insect, often associated with decaying matter from livestock and humans. The septic environments in which houseflies live are believed to be a rich source for microbial acquisition. Although the housefly can harbor a wide range of microorganisms, it is not yet well known which microbes are always recurrent, which are dispensable and which environmentally dependent. In the present study, we aim at identifying which microbes are recurrently associated with the housefly gut throughout the species' life cycle and whether their acquisition relies on the fly's living environment. We surveyed three housefly strains-two of them kept under standard laboratory conditions for a long time and one wild-caught. To track any shifts happening throughout the lifecycle of the housefly and to test the consistency of the revealed microbial communities, we sampled houseflies at five developmental stages over the course of four consecutive generations. Both the bacterial and fungal microbiota of five developmental stages were studied for all samples, using amplicon sequencing for the 16S and ITS1 rRNA gene, respectively. Results revealed diverse microbial communities yet consistent for each of the two distinct sampling environments. The wild-caught population showed a more diverse and more distinct gut microbiota than the two laboratory strains, even though the strain was phylogenetically similar and shared geographic origin with one of them. Two bacterial genera, Myroides and Providencia, and two yeasts, Trichosporon and Candida tropicalis, were present in all sampled larvae and pupae, regardless of the strain. Analysis of the provided diet revealed that the flies acquired the yeasts through feeding. Our main findings show that houseflies might lose microbial diversity when reared in controlled environments, however they can maintain a consistent set of bacteria. We conclude that although the environment can facilitate certain microbial transmission routes for the housefly, and despite the fungal microbiota being largely acquired through diet, the larval bacterial gut microbiome remains relatively consistent within the same developmental stage.
Topics: Animals; Bacteria; Gastrointestinal Microbiome; Houseflies; Larva; Microbiota
PubMed: 35778448
DOI: 10.1038/s41598-022-15186-7 -
Frontiers in Microbiology 2022Red swamp crayfish () have become one of the favorite aquatic products in China. The modern farming mode which uses antibiotics to prevent diseases could impact the...
Red swamp crayfish () have become one of the favorite aquatic products in China. The modern farming mode which uses antibiotics to prevent diseases could impact the bacteria in crayfish intestines. Here, we determined the distribution and antimicrobial resistance phenotypes of the selected culturable bacteria in crayfish intestines and characterized an isolate with last-line antibiotic resistance determinant. Totally, 257 strains were isolated from 115 crayfish. These strains were highly diverse, with sp. ( = 94, 36.6%) and sp. ( = 88, 34.2%) being dominant. Other isolates belonged to genera , , , , , , , and . Most strains from crayfish were susceptible to all tested antibiotics. None of the isolates carried last-line antibiotic resistance genes except one isolate with was detected, which is the first report of -positive isolate from red swamp crayfish. Whole-genome sequencing suggested it belonged to ST48 and carried several resistance genes. was located within an Tn-like transposon linked to an external 5 bp sequence (ACTAT) on both sides on a IncHI1B/HI1A/FIA multi-replicon plasmid. This transposon was considered to be acquired by replicative transposition mediated by IS. The emergence of bacteria with last-line antibiotic resistance genes in crayfish poses serious threat to public health since crayfish could act as a reservoir for the transfer of resistance to humans.
PubMed: 35747368
DOI: 10.3389/fmicb.2022.911777