Microbiological Survey Research Articles

Long-term monitoring of the hypogeal Etruscan Tomba degli Scudi, Tarquinia, Italy. Early detection of black spots, investigation of fungal community and evaluation of their biodeterioration potential.

Hypogeal environments with Cultural Heritage interest pose a real challenge for their preservation and conservation. The ancient Etruscan Necropolis of Tarquinia, Italy, consists of 200 tombs decorated with extraordinary mural paintings, of great artistic and historical value. Since the beginning of the restoration campaign in 2016, a regular microbiological survey has been performed in the Tomba degli Scudi. The aim of this study was to investigate the nature of an expansion of black spots on the pictorial layers recently observed. To determine the origin of the black spots in the atrium chamber of the Tomba degli Scudi, the fungal community was sampled using various techniques: cellulose discs, swabs and nylon membranes and investigated by a multi-analytical approach. The obtained results suggest that the identified fungal strains (e.g. Gliomastix murorum and Pseudogymnoascus pannorum) are common to many subterranean environments around the world, such as Lascaux cave. The continuous and long-term monitoring made it possible to detect alterations at an early stage and assess the harmfulness of different fungal strains. This work is a demonstration of the effectiveness of prevention and monitoring actions within these fragile and valuable environments.

Microbial consortia in commercial salmon products: A comparative study using cultivation-dependent and high-throughput sequencing approaches

Despite the widespread consumption of salmon products, an all-round microbiological survey on fresh salmon and smoked salmon products sold on the market directly to consumers remains to be undertaken. The present study conducted a comprehensive microbial investigation employing both conventional cultivation-based techniques and 16S rRNA amplicon sequencing. A total of 120 fresh salmon and 95 smoked salmon products were systematically collected across all four seasons (spring, summer, fall, and winter), accompanied by temperature assessments of each product’s interior. The average aerobic plate counts for fresh salmon and smoked salmon were 3.63 log and 1.36 log CFU/g, respectively, and the highest seasonal concentrations occurred in summer. The average coliform count was higher in fresh salmon (1.50 log CFU/g) than in smoked salmon products (1.12 log CFU/g). Although smoked salmon exhibited CFU counts similar to those of fresh salmon according to culture-based methods, 16S sequencing unveiled a distinct microbial composition. Photobacterium and Pseudomonas, recognized as major spoilage-related microorganisms, were the predominant genera in all products, but especially in fresh salmon. Smoked salmon exhibited diverse variations in bacterial composition compared to fresh salmon. Three types of lactic acid bacteria—Leuconostoc, Lactobacillus, and Lactococcus—were found to be significantly more abundant in smoked salmon than in fresh salmon. The outcomes of this study contribute to an enhanced understanding of retail salmon products, shedding light on crucial areas for investigation and suggesting potential interventions regarding both sales and production of salmon products.

Temporal evolution of bacterial species and their antimicrobial resistance characteristics in wound infections of war-related injuries in Ukraine from 2014 to 2023

This study continues surveillance of antimicrobial resistance associated with combat injuries in Ukraine. To compare species composition, antibiotic resistance profiles, and emergence of new resistance genes between 2014-2020 and 2022-2023. This was a retrospective multi-centre microbiological survey in Ukrainian hospitals. Antibiotic susceptibility, whole-genome sequencing and multi-locus sequence typing were conducted on 154 organisms obtained from 125 casualties between 2022 and 2023. The data revealed a predominance of Gram-negative bacteria, particularly Acinetobacter baumannii (35.7%), Pseudomonas aeruginosa (14.9%) and Klebsiella pneumoniae (20.7%). High levels of carbapenem resistance were observed among A.baumannii {meropenem 72.2% [39/54, 95% confidence interval (CI) 58.4-83.5]; imipenem 66.7% (36/54, 95% CI 52.5-78.9)}, K.pneumoniae [meropenem 90.6% (29/32, 95% CI 75.0-98.0); imipenem 81.2% (26/32, 95% CI 63.6-92.8)] and P.aeruginosa [meropenem 47.8% (11/23, 95% CI 26.8-69.4); imipenem 60.8% (14/23, 95% CI 38.5-80.3)] strains. A.baumannii sequence type (ST)-78 and ST-400 were prevalent from 2014 to 2020, while five strains of ST-1077 were newly identified in 2022-2023. P. aeruginosa strains showed diversity across 16 STs, with ST-773 increasing in frequency and new STs emerging, but lacking carbapenemase genes. K.pneumoniae exhibited increased genetic diversity over time, with three STs from 2014 to 2020 and six new STs, including blaNDM-1, blaOXA-48 and blaKPC2 carriers, in 2022-2023. The prevalence of multi-drug-resistant isolates with STs associated with a high risk of global dissemination is increasing.

A microbiological survey approach to understanding the virulence factors of Pseudomonas species in healthcare sinks

Hospital water is involved in both the prevention and spread of healthcare-associated infections (HCAIs). Handwashing is key to reducing the transmission of pathogens, yet numerous outbreaks have been found to be caused by organisms within sinks, taps and showers. Pseudomonas aeruginosa and increasingly non-aeruginosa Pseudomonas cause waterborne HCAI, however, little is known about the virulence potential of Pseudomonas species found within hospital environments. Swabs were taken from 62 sinks within two newly opened wards at Great Ormond Street Hospital, samples were taken before and after the wards opened to understand the impact of patient occupancy on sink micro-organisms. Culturable bacteria were identified by MALDI-TOF and virulence factors assessed through phenotypic methods. A total of 106 bacterial isolates were recovered including 24 Pseudomonas isolates. Of these 25% were identified as P.oleovorans, 21% P.aeruginosa, 17% P.composti, 13% P.alicalipha, 8% P.monteilii, 4% P.putida, 4% P.stutzeri and 8% could only be identified to genus level by MALDI-TOF. Differences were seen in both the number of Pseudomonas isolates and virulence production between the two wards, overall 25% of the Pseudomonas isolates produced pigment, 58% were capable of haemolysis, 87.5% were able to swim, 83.3% were capable of twitching motility, 33.3% produced alkaline protease and 8.3% produced gelatinase. Results suggest that patients may be back-contaminating sinks with colonizing organisms which has ongoing implications for infection prevention and control. Additionally, this work highlights the ability of non-aeruginosa Pseudomonas to produce virulence factors traditionally associated with P.aeruginosa.

Microbiological survey and genomic analysis of Cronobacter sakazakii strains isolated from US households and retail foods.

Cronobacter sakazakii is an opportunistic pathogen that can cause significant morbidity and mortality in neonates. Its transmission dynamics are poorly understood, though powered infant formula (PIF) is thought to be the major transmission vehicle. How the PIF becomes contaminated remains unknown. Our survey shows that roughly 1/4 of US homes are contaminated with Cronobacter sakazakii, particularly in the kitchen setting. Our analyses suggest that the domestic environment may contribute to contamination of PIF and provides insights into mitigating the risk of transmission.

Phenotypic and genotypic analysis of antimicrobial resistance and population structure of gastroenteritis-related Aeromonas isolates

BackgroundThe population structure and the correlation between antimicrobial resistance (AMR) phenotypes and genotypes in Aeromonas species isolated from patients with gastroenteritis are not well understood. The aims of the study were to: (1) investigate the antimicrobial susceptibility profiles of Aeromonas species isolated from patients with gastroenteritis; (2) explore the relationship between AMR genes and resistance phenotypes; and (3) describe the population structure of these isolates and provide evidence of transmission events among them.MethodsThis microbiological survey was performed at the Microbiology Laboratory of the Emek Medical Center in Afula, Israel. Cultivation of Aeromonas was attempted from stool samples that tested positive by PCR. Antimicrobial susceptibility testing (AST) was performed using the Sensititre GN3F microdilution panel. Whole genome sequencing (WGS) was done using the Illumina NextSeq500/550 system. Phylogenetic studies involved multi-locus sequence typing (MLST) and core genome (cg) MLST. Resistance mechanisms were identified using the Comprehensive Antibiotic Resistance Database and compared with the AST results.ResultsThe study included 67 patient-unique isolates. The species that were identified included A. caviae (n = 58), A. dhakensis (n = 3), A. media (n = 2), A. veronii (n = 2) and A. hydrophila (n = 2). Isolates were almost uniformly susceptible to amikacin, gentamicin, aztreonam, cefepime, ceftazidime, ciprofloxacin and meropenem. All isolates with the exception of 1–2 isolates were resistant to ampicillin, cefazolin and ampicillin-sulbactam which was compatible with the presence of the blaOXA genes. Variable resistance rates were observed to cefuroxime, cefoxitin, ceftriaxone, piperacillin-tazobactam that were not correlated with the presence of other β-lactamase genes. Resistance to tetracycline and trimethoprim-sulfamethoxazole correlated with the presence of tetA and sul1, respectively. The population structure of A. caviae was highly diverse with the minority of the isolates (16/57) clustering into six defined sequence types. A cgMLST-based distance of four genes was found in one pair of isolates, suggesting common source transmission.ConclusionsA. caviae is the dominant species related to gastroenteritis and is characterized by a diverse population structure, with almost no evidence for common-source transmission. Resistance rates to most antimicrobial agents were low and partially matched with the presence of resistance genes.

Microbiological survey and physicochemical analysis of Moroccan durum, soft and red wheat landraces

Morocco possesses a significant genetic diversity of wheat cultivars in the form of landraces conserved by local farmers in several regions. This study aimed to evaluate the microbiological quality of refined flour and bran derived from 75 samples of Moroccan durum, soft, and red wheat landraces and to estimate their microbiological stability for controlling and preventing undesirable microbial proliferation. Various microbial and physicochemical parameters were evaluated according to ISO and AOAC standards, and results were interpreted based on Codex Alimentarius Commission regulation. Compliance of the analyzed refined flour and bran samples with current regulatory limits and satisfactory microbiological quality were observed. The phenotypic characterization revealed the identification of 16 yeast species belonging to the genera Trichosporon, Candida, Cryptococcus, Rhodotorula, and Saccharomyces, which had not been previously explored. Furthermore, the biodiversity of lactic acid bacteria is notably characterized by the predominance of Pediococcus acidilactici and Lactobacillus plantarum species. The analysis of moisture content and water activity exhibited values falling below the maximum limits defined by international standards, demonstrating the effectiveness of the implemented processing and storage practices. The neutral pH recorded confirms the absence of excessive proliferation of the assessed microbial contaminants. The abundant availability of carbohydrates, lipids, proteins, and minerals creates a favorable non-competitive environment essential for maintaining their functional stability in the analyzed samples. These findings hold significant implications for the agricultural and food industries, providing insights into preserving indigenous wheat varieties and producing safe wheat-based products with high nutritional quality.

Residual risk of Pseudomonas aeruginosa waterborne contamination in an intensive care unit despite the presence of filters at all water points-of-use

To assess the residual risk of waterborne contamination by Pseudomonas aeruginosa from a water network colonized by a single genotype [sequence type (ST) 299] despite the presence of antimicrobial filters in a medical intensive care unit (ICU). During the first 19-month period since the ICU opened, contamination of the water network was assessed monthly by collecting water upstream of the filters. Downstream water was also sampled to assess the efficiency of the filters. P.aeruginosa isolates from patients were collected and compared with the waterborne ST299 P.aeruginosa by multiplex-rep polymerase chain reaction (PCR), pulsed-field gel electrophoresis (PFGE) and whole-genome sequencing. Cross-transmission events by other genotypes of P.aeruginosa were also assessed. Overall, 1.3% of 449 samples of filtered water were positive for P.aeruginosa in inoculum, varying between 1 and 104colony-forming units/100mL according to the tap. All P.aeruginosa hydric isolates belonged to ST299 and displayed fewer than two single nucleotide polymorphisms (SNPs). Among 278 clinical isolates from 122 patients, 10 isolates in five patients showed identical profiles to the hydric ST299 clone on both multiplex-rep PCR and PFGE, and differed by an average of fewer than five SNPs, confirming the water network reservoir as the source of contamination by P.aeruginosa for 4.09% of patients. Cross-transmission events by other genotypes of P.aeruginosa were responsible for the contamination of 1.75% of patients. Antimicrobial filters are not sufficient to protect patients from waterborne pathogens when the water network is highly contaminated. A microbiological survey of filtered water may be needed in units hosting patients at risk of P.aeruginosa infections, even when all water points-of-use are fitted with filters.

87 Functional rumen microbiological survey of triplet-bearing Polypay ewes from parturition to weaning

Abstract Ewes transitioning from late gestation to early lactation face a number of challenges including physiological stress, dietary changes, and metabolic adaptations, particularly when bearing and rearing multiple offspring. Furthermore, rumen microbial composition and function has been correlated with milk production and nutrient density in transitioning dairy cows. However, limited research has evaluated the rumen microbial community of ewes during early lactation. The objective of this study was to conduct a functional microbiological survey of the ewe rumen from parturition to weaning. We hypothesized that ewes would experience fermentative disturbances post-parturition and that the rumen microbiota, and consequently, circulating metabolites, would recover over time. Nine multiparous Polypay ewes bearing triplets were fed a lactation diet consisting of alfalfa hay and concentrate mix to meet protein and energy requirements. One lamb of each triplet set was randomly selected and placed on milk replacer 24 h after birth. The two lambs remaining on the ewe were weaned at 56 d of age. Blood and rumen samples from ewes were collected via jugular venipuncture and oral intubation, respectively, at 2, 7, and 15 d of lactation in addition to at the time of weaning. Rumen bacterial functional guilds were enumerated via serial dilution. Ruminal short-chain fatty acids (SCFA) were quantified via HPLC and serum metabolites by LC-MS. All data were analyzed using PROC Mixed with repeated measures in SAS (v. 9.4, SAS Inst. Inc., Cary, NC). Total starch-utilizing bacteria remained steady during early lactation but increased 100-fold by weaning (P = 0.03). In contrast, the starch-utilizing guild sub-population lactobacilli increased 10-fold by d 15 of lactation (P < 0.01) and remained constant through weaning (P > 0.05). No differences were found in the viable number of rumen cellulolytic bacteria (P = 0.37) throughout the study. Ruminal propionate concentrations increased 35% (P = 0.04) from d 2 to weaning and serum propionate (36.8 ± 4.42 µM; P = 0.08) and glucose (59.8 ± 2.97 mg dL-1; P < 0.01) peaked on d 15 of lactation. While ruminal acetate did not fluctuate in early lactation, it increased 58% by weaning (P < 0.01) leading to an 88% increase in serum acetate (P < 0.01). Ruminal butyrate increased 49% by d 15 (P = 0.01) and this was reflected in a 7-fold increase in serum butyrate (P = 0.02). However, serum β-hydroxybutyrate did not differ from parturition through weaning (P = 0.51). Results of this experiment demonstrate that rumen bacterial functional guilds, as well as rumen and serum metabolites, were lowest two days post-parturition and increased over the course of lactation. This may suggest that ruminal fermentation is suppressed post-parturition, which could have implications for early lactation management strategies of triplet-bearing ewes.

Microbiological Survey and Evaluation of Antimicrobial Susceptibility Patterns of Microorganisms Obtained from Suspect Cases of Canine Otitis Externa in Gran Canaria, Spain.

A retrospective study of microbiological laboratory results from 2020 to 2022, obtained from a veterinary diagnostic laboratory of the island of Gran Canaria, Spain, focused on canine otitis cases, was performed. The objective of this study was to analyze the pathogen distribution, antimicrobial susceptibility, prevalence of multidrug resistant phenotypes and the role of coinfections in otitis cases in order to provide up-to-date evidence that could support effective control strategies for this prevalent pathology. A total of 604 submissions were processed for the diagnosis of canine external otitis. Of the samples analyzed, 472 were positive for bacterial or fungal growth (78.1%; 95% CI: 74.8-81.4%). A total of 558 microbiological diagnoses were obtained, divided in 421 bacterial (75.4%; 95% CI: 71.8-79.0%) and 137 fungal (24.6%; 95% CI: 20.9-28.1%) identifications. Staphylococcus pseudintermedius, Malassezia pachydermatis and Pseudomonas aeruginosa were the most prevalent microorganisms detected in clinical cases of otitis. High level antimicrobial resistance was found for Pseudomonas aeruginosa (30.7%), Proteus mirabilis (29.4%), Staphylococcus pseudintermedius (25.1%) and Escherichia coli (19%). Multidrug-resistant phenotypes were observed in 47% of the bacteria isolated. In addition, a 26.4% prevalence of methicillin-resistant Staphylococcus pseudintermedius was detected. The high prevalence of antimicrobial resistant phenotypes in these bacteria highlights the current necessity for constant up-to-date prevalence and antimicrobial susceptibility data that can support evidence-based strategies to effectively tackle this animal and public health concern.

Microbiome analysis reveals the differences in gut fungal community between Dutch Warmblood and Mongolian horses

Similar to gut bacterial community, gut fungal community are also an important part of the gut microbiota and play crucial roles in host immune regulation and metabolism. However, most studies have focused on the gut bacterial community, and research on the gut fungal community has been limited. Dutch Warmblood (DWH) and Mongolian horses (MGH) are important equine breeds, but little research has been done on their gut fungal community. Here, we assessed differences in gut fungal community between two horse species. Results showed that a total of 2159 OTUs were found in the Dutch Warmblood and Mongolian horses, of which 308 were common. Between-group analyzes of microbial diversity showed no differences in the alpha and beta diversity of gut fungal community between the two horse species. Microbiological taxonomic surveys showed that the dominant fungal phyla (Neocallimastigomycota and Ascomycota) and genera (unclassified_Neocallimastigaceae and Anaeromyces) were the same without being affected by species. Although the types of dominant fungal phyla did not change, the abundances of some fungal genera changed significantly. Results of Metastats analysis showed that there were a total of 206 fungal genera that were significantly different between the two horses, among which 78 genera showed an increase and 127 genera significantly decreased in Dutch Warmblood horses compared with Mongolian horses. In conclusion, this study investigated the composition and structure of the gut fungal community of Dutch Warmblood and Mongolian horses and found significant differences in gut fungal community between both breeds. Notably, this is the first exploration of the differences in the gut fungal community of both breeds, which may help to understand the distribution characteristics of the gut fungal community of different breeds of horses and reveal the differences in the traits of different horses.

Microbiological Survey of Animate and Inanimate Surfaces in a Correctional Center, South-South, Nigeria

Correctional centers (formerly referred to as prisons, in Nigeria) are facilities where offenders of the law are kept after been convicted of a crime. Many factors have in recent time contributed to an increasing rate of morbidity and mortality in these facilities, including overcrowding, poor sanitary conditions, inadequate ventilation, extreme temperatures, inadequate means for maintaining personal hygiene, lack of access to clean drinking water, and nutritionally deficient food. This study therefore centered on the microbiological survey of animate and inanimate surfaces in a correctional center, South-South Nigeria. For this research, a total of 150 samples (100 from skin (upper arm) and 50 from wall surfaces) were collected from the inmate skins and inanimate surfaces, using sterile swab sticks and were immediately transported to the Department of Microbiology Laboratory, Rivers State University for analyses using standard microbiological procedures. Data obtained from the study showed the inmates within the age bracket 21-30 were the highest (44%) while the age bracket 71-80 represented the lowest (1%) number of inmates. The study showed that male inmates represented 75% of the prisoners studied while the female represented 25%. The result showed that 37% of the studied inmates had spent 2-4 years in the correctional center while the least period of exposure or stay in the facility was recorded for 13 years in the correctional center, which represented 1% of the inmates. The age bracket 21-30 recorded the highest number of microorganisms (39) and 71-80 showed the least (1). Different microbial species were recovered from the skin of the inmates and included Staphylococcus spp, Escherichia coli, Streptococcus spp, Klebsiella spp, Bacillus spp, and Aspergillus spp., with Staphylococcus spp showing the highest occurrence of 48%, while Klebsiella spp had the least occurrence (1%).The study indicated that the correctional center could pose serious environmental health concerns, requiring public health interventions. Adequate personal hygiene should be encouraged among the inmates. Regular sanitation as well as adequate healthcare and routine checkup should therefore be made available to the inmates.

Recalls of tattoo and permanent makeup inks in the United States and a follow-up microbiological survey of inks with a previous recall history.

In this study, we collected voluntary recall records of tattoo and permanent makeup ink from the U.S. Food and Drug Administration (US FDA) Enforcement Report Database. The recall records contain information, such as recall date, manufacturer, ink color, reason for recall, and the microorganisms detected from the ink samples. Between 2003 and 2021, a total of 15 voluntary tattoo ink recalls occurred in the U.S. market, involving over 200 tattoo inks marketed by 13 manufacturers and one distributor. Fourteen recalls were due to microbial contamination, and one recall was due to allergic reaction. As follow-up, a microbiological survey of 28 tattoo inks of new batches from seven manufacturers having products that were previously recalled was conducted. Aerobic plate count (APC) and enrichment culture methods based on the FDA's Bacteriological Analytical Manual (BAM) were used to detect microbial contamination. The results revealed that six out of 28 tattoo inks were contaminated with bacteria and were produced by two manufacturers. The level of microbial contamination was less than 250 CFU/g in three of the tattoo inks and between 1 × 103 and 1 × 105 CFU/g in the other three inks. Eleven bacterial isolates were identified, including spore-forming Bacillus-related species and potentially pathogenic species. Overall, this study shows that some tattoo ink products produced by manufacturers with a recall history continue to be contaminated with microorganisms. This highlights the need for ongoing monitoring and quality control of such products.

Implication of Sodium Hypochlorite as a Sanitizer in Ready-to-Eat Salad Processing and Advantages of the Use of Alternative Rapid Bacterial Detection Methods.

The use of disinfection agents in the washing processing of ready-to-eat (RTE) vegetables, especially sodium hypochlorite, is a common industrial practice performed to enhance microbiological quality. However, some studies have reported a restart of bacterial growth and a substantial increase in bacterial load during early storage associated with the use of disinfection agents, which might represent a risk for consumers. We evaluated the effect of sodium hypochlorite on bacterial growth trends during the shelf-life in Lactuca sativa, simulating the industrial procedures for RTE vegetable packaging. Immediately after sodium hypochlorite treatment, an effective abatement of the bacterial load was observed, followed by a restart of growth throughout storage. After 5 days, the bacterial load was close to that reached by the control samples, indicating that the net increase in bacterial load was significantly higher in the treated samples. This might be ascribed to the reduction in competitive microflora and/or to the induction of adaptive responses by resting bacteria, which might select disinfectant-resistant bacteria. These findings elicit some concerns about the actual duration of the shelf-life; products might decrease their microbiological quality earlier during storage, pointing out the need to better clarify the impact of sodium hypochlorite as a sanitizer to closer consider its use in RTE vegetable processing. Furthermore, due to the importance of the rapid estimation of bacterial load and the early detection of foodborne pathogens throughout the food chain, the accuracy of the rapid bacteria detection method, the Micro Biological Survey (MBS), and its effectiveness for microbiological analyses of RTE vegetables were evaluated.

Microbiological Survey and Antimicrobial Resistance of Foodborne Bacteria in Select Meat Products and Ethnic Food Products Procured from Food Desert Retail Outlets in Central Virginia, USA.

In food desert areas, low-income households without convenient transportation often shop at small, independently owned corner markets and convenience stores (SIOMs). Studies indicate a higher potential for reduced product quality and safety of foods sold at SIOMs, with more critical and non-critical code violations in the region. This study aimed to assess the difference in market scale on the microbiological quality in select food products procured from food deserts in Central Virginia. A total of 326 samples consisting of meat products (i.e., ground beef, chicken, and sausage), ethnic food products (i.e., ox tail, stock fish bite, egusi ground, and saffron powder), and food packaging surfaces procured from ten registered SIOMs and nine large chain supermarkets (LCSMs) between August 2018 and March 2020 were evaluated. Higher levels of aerobic mesophile and coliform counts were found in SIOMs-acquired samples than in LCSMs-acquired samples, as demonstrated by the lower food safety compliance rate of SIOMs. Regardless of SIOMs or LCSMs, Campylobacter, E. coli, Listeria, and Salmonella were detected in 3.6%, 20.9%, 5.5%, and 2.7% of samples, respectively. The majorities of Campylobacter (75%, 6/8) and Salmonella (83.3%, 5/6) detected were from SIOMs-acquired samples including ethnic food products. Among the tested antimicrobials, AMP (100%) and TOB (100%) showed the highest frequency of resistance among Campylobacter, TCY (69.9%) among E. coli, NAL (100%) among Listeria, and TCY (50%) among Salmonella, respectively. The prevalence of multi-drug resistance (MDR) and non-susceptibility in Campylobacter and non-susceptibility in Listeria isolated from SIOMs-acquired food products were lower than those isolated from LCSMs-acquired samples. A higher price of the same brand name commodity sold at SIOMs than those sold at LCSMs was also observed, indicating an increased financial burden to economically challenged residents in food desert areas, in addition to food safety concerns. Elaborated and in-depth research on a larger-scale sample size with a greater diversity of products is needed to determine and intervene in the cause(s) of the observed differences in the prevalence of the pathogens and AMR profiles.

Tracking microbial quality, safety and environmental contamination sources in artisanal goat cheesemaking factories

A harmonised microbiological survey was performed in two artisanal factories of raw goat milk cheeses (A and B) located in the Andalusian region (Spain). A total of 165 different control points or samples (raw materials, final products, food-contact surfaces [FCS], and air) were examined as microbial and pathogen sources of contamination of artisanal goat raw milk cheeses. For raw milk samples analysed from both producers, the concentrations of aerobic-mesophilic bacteria (AMB), total coliforms, coagulase-positive Staphylococcus spp. (CPS), lactic-acid bacteria (LAB) and moulds and yeasts ranged between 3.48 and 8.59, 2.45–5.48, 3.42–4.81, 4.99–8.59 and 3.35–6.85 log cfu/mL respectively. For the same microbial groups, the analysis of raw milk cheeses revealed concentrations ranging from 7.82 to 8.88, 2.00–6.82, 2.00–5.28, 8.11–9.57 and 2.00–5.76 log cfu/g, respectively. Although the raw material analysed from producer A presented higher microbial loads and between-batch variability, it was B the producer with the most loaded final products. Regarding the microbial air quality, the fermentation area, storage room, milk reception and packaging room were the most AMB loaded places, while the ripening chamber was the area with higher fungal loads in bioareosol from both producers. Conveyor belts, cutting machine, storage boxes and brine tank were highlighted as the most contaminated FCS evaluated. Staphylococcus aureus was the only pathogen detected within the set of 51 isolates from samples as revealed by MALDI-TOF and molecular PCR, with a prevalence of 12.5% for samples from the producer B. The public health risk attributed to the consumption of artisanal goat cheese should not be neglected, and may consider the whole cheesemaking processing chain, from microbiological quality of raw milk to the ready-to-eat final product, especially concerning the presence of S. aureus.

Microbial communities in the deep-sea sediments of the South São Paulo Plateau, Southwestern Atlantic Ocean.

Microbial communities play a key role in the ocean, acting as primary producers, nutrient recyclers, and energy providers. The São Paulo Plateau is a region located on the southeastern coast of Brazil within economic importance, due to its oil and gas reservoirs. With this focus, this study examined the diversity and composition of microbial communities in marine sediments located at three oceanographic stations in the southern region of São Paulo Plateau using the HOV Shinkai 6500 in 2013. The 16S rRNA gene was sequenced using the universal primers (515F and 926R) by the Illumina Miseq platform. The taxonomic compositions of samples recovered from SP3 station were markedly distinct from those obtained from SP1 and SP2. Although all three stations exhibited a high abundance of Gammaproteobacteria (> 15%), this taxon dominated more than 90% of composition of the A and C sediment layers at SP3. The highest abundance of the archaeal class Nitrososphaeria was presented at SP1, mainly at layer C (~ 21%), being absent at SP3 station. The prediction of chemoheterotrophy and fermentation as important microbial functions was supported by the data. Additionally, other metabolic pathways related to the cycles of nitrogen, carbon and sulfur were also predicted. The core microbiome analysis comprised only two ASVs. Our study contributes to a better understanding of microbial communities in an economically important little-explored region. This is the third microbiological survey in plateau sediments and the first focused on the southern region.

Microbiological safety and quality survey of some dairy confectioneries with cream filling and topping.

Dairy confectionaries are recently categorized as an important part of different consumers' diets with increasing demand for cream-based cakes "Tourta" and gateau which are used as celebrating food for almost all occasions and celebrations. The study was designed for evaluating general quality and safety of such products. 100 cream-based (for topping and filing) samples; 50 cakes "Tourta" and 50 gateau, were purchased separately from several pastry shops covering international, national, and local brands in Great Cairo, Egypt, and subjected to microbiological analysis. Results showed that international brands were the best for gateau samples while national brands were the best quality for cake samples. Regardless of the brand, the general hygienic quality of the cake product "Tourta" was lower on an average total colony, coliforms, yeast, and mold counts as compared with the gateau product. Although coliforms were found in 100% of the examined samples with the highest mean value of 33 × 102 ± 7.0 × 102 CFU/g in local gateau samples, Escherichia coli and Salmonella spp. could not be detected in these samples. Staphylococcus aureus was isolated from 8% of the total examined samples with the highest incidence of (22.2%) and a mean count of 38 × 10 ± 6.0 × 10 CFU/g in local brand gateau samples. Bacillus cereus was extensively isolated with the highest incidence in cake samples (32%) and mean counts higher than 103 in all of the examined samples. Bacillus cereus strains have harbored more than one toxigenic gene. In this aspect, nhe gene was the most predominant one as it was detected in 100% of the examined isolates, followed by cytK gene in 80%, whilehbl and ces genes could not be found. According to the Egyptian Standard specifications for cake (ES: 4037/2020), a higher acceptability degree was reported for the international brand gateau and cake "Tourta" samples. The incidence of using any preservative as an inhibitory substance was also analyzed generally using the Bacillus subtilis disk assay technique, but all samples were negative using this technique indicating the need for a more advanced technique for its detection such as using high-performance liquid chromatography. Finally, it was concluded that; more attention is needed to cream-based cakes' quality and safety, with essential modification required in the standards of cakes in Egypt.

The MBS microbial rapid detection system for rapid detection of major pathogenic bacteria in feed: comparison with plate counting method

The current methods for detecting pathogenic bacteria in feed require high technique and take a long time. The Micro Biological Survey (MBS) rapid detection system is a simple, economical and rapid microbial detection method. The purpose of this experiment was to compare the detection of Escherichia coli (E. coli), Salmonella, Staphylococcus aureus (S. aureus), Listeria monocytogenes (LM), coliform (COLI) and total viable count (TVC) in feed by the MBS rapid microbial detection system and plate counting method (PCM). The results showed that the limit of quantitation, recovery rate and coefficient of variation of the MBS microbial rapid detection system are better than the plate counting method. When detecting the pathogenic bacteria content in artificially contaminated feed, the MBS rapid microbial detection system was positively correlated with the PCM. When the MBS microbial rapid detection system and PCM were used to detect the collected real feed samples, there was no significant difference in the detection results of the two methods in most of the feed samples. In summary, the MBS microbial rapid detection system is the most convenient and rapid detection method and is suitable for promotion and application in production lines.

Carbonatogenic bacteria on the ‘Motya Charioteer’ sculpture

The ‘Motya Charioteer’ marble statue, a masterpiece of ancient Greek sculpting, was discovered in 1979 on the island of Motya, Sicily. A general assessment of the statue's conditions in 2008 revealed that the marble has lost its luster and started to show some microcracks. In 2019 and in 2020, microbiological surveys were conducted to assess the marble's biodeterioration through the identification of bacteria capable of metabolizing calcium carbonate and damaging the statue. Bacterial strains with calcium carbonate dissolution properties were isolated exclusively from the damaged areas of the statue; among 31 strains showing calcium carbonate metabolism (precipitation and/or dissolution), 23 were bacilli. While causation cannot be confirmed, these bacterial strains are certainly capable of dissolving marble leading to statue degradation. In two damaged areas of the statue, Staphylococcus haemolyticus, a common component of human skin flora was identified. This strain demonstrated a fast calcium carbonate dissolution property, which has not previously reported for this species. Finally, two strains (Lysinibacillus fusiformis and Metabacillus litoralis), showed carbonatogenic features perfectly suitable for a bioconsolidation intervention on the sculpture.