Recent Records on Bacterial Opportunistic Infections via the Dietary Route

This narrative review was aimed at identifying the opportunistic bacterial pathogens that can be transmitted by contaminated food and represent a current threat for patients particularly susceptible to infections because of underlying conditions or predisposing factors. The analysis was focused on recent case or outbreak reports and systematic reviews published in the years 2019 to 2023 and resulted in sorting 24 bacterial groups comprising the genera or species able to cause a variety of systemic or invasive infections if ingested with food or drinking water. These included both bacteria known to cause mild infections in immunocompetent persons and bacteria considered to be innocuous, which are used in food fermentation or as probiotics. No recent cases of infections transmitted through dietary routes were reported for the critical nosocomial pathogens widely found in food products, primarily Acinetobacter baumannii and Klebsiella pneumoniae. However, the very first sources of their introduction into the clinical environment still need to be established. In many instances, risky dietary habits, such as eating raw fish, seafood, raw meat, unpasteurized milk, and their derived products or the lack of control in fermentation processes, has led to the reported illnesses, pointing out the necessity to improve the hygiene of production and consumer awareness of the risks.

Impact of Fibrous Microplastic Pollution on Commercial Seafood and Consumer Health: A Review

The omnipresence of microfibers in marine environments has raised concerns about their availability to aquatic biota, including commercial fish species. Due to their tiny size and wide distribution, microfibers may be ingested by wild-captured pelagic or benthic fish and farmed species. Humans are exposed via seafood consumption. Despite the fact that research on the impact of microfibers on marine biota is increasing, knowledge on their role in food security and safety is limited. The present review aims to examine the current knowledge about microfiber contamination in commercially relevant fish species, their impact on the marine food chain, and their probable threat to consumer health. The available information suggests that among the marine biota, edible species are also contaminated, but there is an urgent need to standardize data collection methods to assess the extent of microfiber occurrence in seafood. In this context, natural microfibers should also be investigated. A multidisciplinary approach to the microfiber issue that recognizes the interrelationship and connection of environmental health with that of animals and humans should be used, leading to the application of strategies to reduce microfiber pollution through the control of the sources and the development of remediation technologies.

Autochthonous Cultures to Improve Safety and Standardize Quality of Traditional Dry Fermented Meats

Traditional dry fermented meat products are obtained artisanally in many countries, where they represent a gastronomic heritage well distinguished from industrial counterparts. This food category is most often obtained from red meat, a food commodity that is under attack because of evidence of increased risk of cancer and degenerative diseases with high consumption. However, traditional fermented meat products are intended for moderate consumption and gastronomic experience, and, as such, their production must be continued, which would also help safeguard the culture and economy of the geographical areas of origin. In this review, the main risks attributed to these products are considered, and how these risks are reduced by the application of autochthonous microbial cultures is highlighted by reviewing studies reporting the effects of autochthonous lactic acid bacteria (LAB), coagulase negative staphylococci (CNS), Debaryomyces hansenii and Penicillium nalgiovense on microbiological and chemical safety and on sensory attributes. The role of dry fermented sausages as a source of microorganisms that can be beneficial to the host is also considered. From the results of the studies reviewed here it appears that the development of autochthonous cultures for these foods can ensure safety and stabilize sensory characteristics and has the capacity to be extended to a larger variety of traditional products.

Research and characterization of fibrous microplastics and natural microfibers in pelagic and benthic fish species of commercial interest

The ingestion of synthetic microfibers, the most prevalent type of microplastics in marine environments, and natural fibers was assessed in Engraulis engrasicolus and Mullus barbatus, two commercially important fish species in the Mediterranean Sea. Microfibers were isolated from the fish gastrointestinal tract using a 10% potassium hydroxide solution. For the microfiber characterization, the evaluation of specific morphological features using a light microscope, coupled with the Fourier-transform infrared (FTIR) analysis of a subsample of isolated particles, was applied. The preliminary results showed the occurrence of microfibers in 53 and 60% of European anchovy and Red mullet, respectively. A mean of 6.9 microfibers/individual was detected in anchovies, while on average Red mullet samples contained 9.2 microfibers/individual. The most common colors of fibers in both species were black, blue, and transparent. Visual characterization of fibers allowed the classification of 40% of the items as synthetic microfibers. FTIR spectroscopy confirmed the visual classification by fiber morphology. Microfibers were made of different typologies of polymers, represented by cellulose, cotton, and polyester. These findings confirm as the wide distribution of fibrous microplastics, and natural microfibers may impact both pelagic and deep-sea trophic webs. Despite the presence of microfibers in fish species poses a potential risk to human health, the literature is scarce regarding studies on the uptake by commercial marine fish mostly due to methodological issues. The visual characterization, corroborated by spectroscopic techniques, may be useful to differentiate synthetic and natural fibers, representing a fast and easy method to assess fibrous microplastic pollution in commercially important fish species.

Microplastics in Fish and Fishery Products and Risks for Human Health: A Review

In recent years, plastic waste has become a universally significant environmental problem. Ingestion of food and water contaminated with microplastics is the main route of human exposure. Fishery products are an important source of microplastics in the human diet. Once ingested, microplastics reach the gastrointestinal tract and can be absorbed causing oxidative stress, cytotoxicity, and translocation to other tissues. Furthermore, microplastics can release chemical substances (organic and inorganic) present in their matrix or previously absorbed from the environment and act as carriers of microorganisms. Additives present in microplastics such as polybrominated diphenyl ethers (PBDE), bisphenol A (BPA), nonylphenol (NP), octylphenol (OP), and potentially toxic elements can be harmful for humans. However, to date, the data we have are not sufficient to perform a reliable assessment of the risks to human health. Further studies on the toxicokinetics and toxicity of microplastics in humans are needed.

Diversity and Safety Aspects of Coagulase-Negative Staphylococci in Ventricina del Vastese Italian Dry Fermented Sausage

Ventricina del Vastese is a traditional dry fermented sausage from Central Italy not yet characterized for the occurrence, identity and safety of coagulase-negative staphylococci (CNS), a bacterial group technologically important for this kind of product. Therefore, in this study, 98 CNS isolates from four manufacturers were differentiated using repetitive element palindromic PCR (Rep-PCR) and identified using 16S rRNA gene sequencing. These were examined for genes encoding biogenic amine (BA) production, resistance to aminoglycosides, β-lactams, tetracyclines and staphylococcal enterotoxins (SEs). Staphylococcus succinus (55%) predominated, followed by S. xylosus (30%), S. epidermidis (7.4%), S. equorum (3.1%), S. saprophyticus (3.1%) and S. warneri (1%). One S. succinus subsp. casei isolate was slightly β-hemolytic. SEs and the histidine decarboxylase gene hdcA were not detected, whereas the tyrosine decarboxylase gene tdcA was detected in four S. xylosus isolates. The blaZ beta-lactamase gene in an S. equorum isolate, tetracycline resistance genes tetK in six S. succinus isolates and tetA in one S. succinus isolate also bearing tetK were found. The product examined is characterized by a peculiar CNS species ratio and a low occurrence and diversity of AR transferable genes than found in other studies, as a probable consequence of production only with meat from animals raised in small farms with extensive rearing systems in which antibiotic usage is infrequent.

Lactobacilli Infection Case Reports in the Last Three Years and Safety Implications

Lactobacilli constitute the dominant microbiota in many fermented foods and comprise widely used probiotics. However, these bacteria cause rare infections mostly in diabetic and immunocompromised subjects in presence of risk factors such as prosthetic hearth valves and dental procedures or caries. The scope of this survey was re-assessing the pathogenic potential of lactobacilli based on the infection case reports published in the last three years. In 2019, 2020, and 2021, total of 17, 15, and 16 cases, respectively, including endocarditis, bacteremia, and other infections, were reported. These annual numbers are higher than those observed previously. Lacticaseibacillus rhamnosus (13 cases), comprising strain GG (ATCC 53103) with established applications in healthcare, L. paracasei (7 cases), Lactobacillus acidophilus (5 cases), L. jensenii (5 cases), Lactiplantibacillus plantarum (3 cases), L. paraplantarum, L. delbrueckii subsp. delbrueckii, L. gasseri, L. paragasseri, Limosilactobacillus fermentum, and L. reuteri (1 case each) were involved. Virulence characterization of two strains that caused infections, a derivative of L. rhamnosus GG and L. paracasei LP10266, indicated that increased biofilm-forming capacity favors pathogenicity and it is determined by variable genetic traits. This survey highlights that the strains of lactobacilli that cause infections are little characterized genetically. Instead, to avoid that these bacteria become a hazard, genetic stability should be periodically re-evaluated by whole genome sequencing (WGS) to ensure that only non-pathogenic variants are administered to vulnerable individuals.

Development of a high-performance liquid chromatography method to assess bisphenol F levels in milk

Bisphenol F (BPF) is a bisphenol A (BPA) analogue. As an endocrine disruptor, BPF shows a similar BPA hormonal activity and greater endocrine effects. To assess BPF levels in milk a selective method based on solvent extraction with acetonitrile, solid-phase extraction (SPE), high-performance liquid chromatography with fluorescence detection (HPLC-FD) system, was developed. The method showed high recovery values (from 97.60 to 107.16%), and good detection and quantification limits (LOD=0.03 μg/L; LOQ=0.1 μg/L). To validate the analytical method, quantitative analyses of n.20 milk samples of whole milk were preliminarily carried out applying a monitoring system based on the control of different stages of pasteurized whole milk processing at a dairy company. The proposed method is simple, sensitive, and might be suitable to detect BPF residues in milk processing. At the dairy company, the occurrence of BPF levels ranging from Collapse

Key Words

• Bisphenol F
• High-performance liquid chromatography method
• Milk

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MESH Headings Collapse

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Affiliation(s)

Serena Santonicola Department of Medicine and Health Sciences, University of Molise, Campobasso
Maria Carmela Ferrante Department of Veterinary Medicine and Animal Production, University of Naples, Italy
Giampaolo Colavita Department of Medicine and Health Sciences, University of Molise, Campobasso
Raffaelina Mercogliano Department of Veterinary Medicine and Animal Production, University of Naples, Italy

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Occurrence of potential plastic microfibers in mussels and anchovies sold for human consumption: Preliminary results

There is a global concern over the impact of microplastics on marine species and trophic webs. Microfibers commonly represent the greater portion of microplastics in the aquatic environment, but little is known about fiber uptake and accumulation by marine biota. The aim of the study was to investigate the potential plastic microfiber contamination in mussels (Mytilus galloprovincialis) and anchovies (Engraulis encrasicolus) from the Tyrrhenian Sea sold for human consumption. Anthropogenic debris was extracted from the digestive tracts of fish and the whole shellfish using a 10% KOH solution and quantified under a light microscope. The preliminary results showed the occurrence of potential plastic and natural microfibers in 73% of the samples. On average mussels contained 1.33 microfibers/g w.w. and 7.66 items/individual, while anchovies contained 9.06 microfibers/individual. Considering that mussels are consumed as a whole, and small pelagic fish, as anchovy, may be eaten without removing the gastrointestinal tract, microfiber contamination may lead to human exposure. More research is required to adequately assess the risk that microplastics, including microfibers, may pose for food safety and human health.

Extraction and identification of microplastics from mussels: Method development and preliminary results

Microplastics (MPs) are an emerging threat to marine ecosystems. One of the primary environmental risks is their bioavailability for aquatic organisms. Some fish and bivalves are of particular interest because their feeding strategies expose them to particles present in the water column. The aim of the study was to assess an extraction method in order to isolate and quantify MPs from fish gastrointestinal tract (n.8) and muscle (n.4), and bivalves (n.8) samples. The accuracy of the method was assessed through the calculation of the recovery percentage in samples spiked with a known number of MPs using microscopic observation. Successively, the extraction was preliminarily applied on n.20 mussels collected from mariculture plants of the Tyrrhenian and the Adriatic Sea. The results of the digestion protocol showed an average extraction yield of 80% in fish gastrointestinal tracts, 90% in fish muscle samples, and 95% in mussels. Preliminary analysis carried out on farmed mussels showed an average abundance of 3.8 items/individual, and 0.5 items/g of tissue, among those black, was the most represented color.

Occurrence of Microplastics in Commercial Seafood under the Perspective of the Human Food Chain. A Review

The occurrence of microplastics in the marine ecosystem and aquatic organisms, their trophic transfer along the food web, and the identification of seafood species as suitable indicators have become a research priority. Despite the high quantity of research in this field, a comparison between the available data and an appropriate risk assessment remains difficult. In this perspective, as an innovative approach, the association of the feeding strategies of commercial seafood and the microplastic level was considered. Further research to assess the occurrence of microplastics in the marine food web, the long-term effects on animals and humans, and the health implications is needed.

Members of the Lactobacillus Genus Complex (LGC) as Opportunistic Pathogens: A Review

Microorganisms belonging to the Lactobacillus genus complex (LGC) are naturally associated or deliberately added to fermented food products and are widely used as probiotic food supplements. Moreover, these bacteria normally colonize the mouth, gastrointestinal (GI) tract, and female genitourinary tract of humans. They exert multiple beneficial effects and are regarded as safe microorganisms. However, infections caused by lactobacilli, mainly endocarditis, bacteremia, and pleuropneumonia, occasionally occur. The relevance of Lactobacillus spp. and other members of the LGC as opportunistic pathogens in humans and related risk factors and predisposing conditions are illustrated in this review article with more emphasis on the species L. rhamnosus that has been more often involved in infection cases. The methods used to identify this species in clinical samples, to distinguish strains and to evaluate traits that can be associated to pathogenicity, as well as future perspectives for improving the identification of potentially pathogenic strains, are outlined.

Introduction of the nudging method in penitentiary facilities in Italy in view of food waste reduction: Preliminary data

The aim of this study was to analyze different aspects of food waste in the specific context of prisons by introducing the nudging method, thanks to the collaboration of District House and Prison of Larino (Italy) involving staff and guests of the penitentiary structure, providing them with the knowledge of the topic and encouraging them to propose creative and effective solutions to prevent and reduce food waste. The study involved n. 50 participants out of total of about 200 prisoners. Data were collected using n.3 questionnaires related to the knowledge of food waste food, the second related to the origin of consumed and food waste and the third collected the participants’ proposals how to reduce food waste. The results show that effects of nudging has awakened the prisoners’ conscience about the social, ethical and economic importance of reducing food waste and a proactive attitude in providing proposals for the reduction of food waste. The most wasted food is bread (35%), pasta (27%) and fresh fruit (20%), provided by the administration because they are considered of inferior quality or prepared and cooked badly. The overwhelming majority (96%) of the participants showed sensitivity about the ethical and economic reasons behind the fight against food waste, making themselves available to contribute to its reduction and suggesting some initiatives. The data collected from the questionnaires related to the causes of waste indicate the need to implement actions aimed at the correct conservation of food and the promotion of good hygiene practices.

Hygienic characteristics and microbiological hazard identification in horse and donkey raw milk

Today the interest toward horse (Equus caballus) and donkey (Equus asinus) milk for human consumption is receiving a renewed attention because of its particular composition, hypoallergenicity, and nutraceutical properties. The realistic perspective of global use of this aliment in balanced diets, especially for infancy and geriatrics, poses the need for a more in depth knowledge on milk hygiene and on the health status of dairy animals, as a prerequisite of consumers' safety. The aim of this paper was to review the available literature on the health and hygiene parameters as well as on the potential microbiological hazards in horse and donkey milk and the risks related to their consumption. Both microbial contamination and somatic cell count are reasonably low in equine milk and also the presence of pathogens, like Escherichia coli O157, Salmonella spp., Campylobacter spp., Yersinia enterocolitica, Brucella spp., Mycobacterium spp., Bacillus cereus, Cronobacter sakazakii, Streptococcus equi subsp. zooepidemicus, Rhodococcus equi, Streptococcus dysgalactiae subsp. equisimilis, Clostridium difficile and Burkholderia mallei is low. However, in those regions of the world where the prevalence of Brucella spp. and Rhodococcus equi is high, the alimentary risks could increase. Similarly, in areas with higher incidence of immunocompromised people, the increased risks should be warned not only for pathogens but also for opportunistic microbiota.

Risk Assessment in the Recovery of Food for Social Solidarity Purposes: Preliminary Data

The most recent study, conducted by Politecnico of Milan, on food surplus management in Italy shows that in the Italian food supply chain the food surplus is around 5.5 million tons/year, and the amount of food wasted is around 5.1 million tons/year. During 2015, the charitable organizations (COs) belonging to the Italian Food Bank Network, active in recovering and distributing food for social solidarity's purposes, reused 381,345 tons of food from 2292 donors. The main supplying sources of the Banco Alimentare Network are: food industries, organized large-scale retail trade and collective catering service. The aim of this study was to analyze several aspects of the food surplus recovery thanks to the collaboration with the Banco Alimentare Foundation Onlus and Caritas Italiana. In particular, two main features were analyzed in the food recovery chain: the microbiological profiles of specific food categories recovered from catering service with the aim to evaluate their conformity in relation to food safety and process criteria. For this purpose 11 samples were analyzed in four different moments: T0, same day of the collection; T1, after four hours of storage at 4°C; T2, 24 hours from the collection (storage at 4°C); T3, after four days at frozen storage (-18°C). For all samples several microbiological parameters were investigated: enumeration of mesophilic aerobic bacteria (AFNOR 3M 01/1-09/89), enumeration of Enterobacteriaceae (AFNOR 3M 01/06-09/97), enumeration of E. coli (AFNOR 3M 01/08-06/01), enumeration of coagulase-positive Staphylococci AFNOR 3M 01/9-04/03 A), enumeration of Bacillus cereus (UNI EN ISO 7932:2005), research of Salmonella spp. [UNI EN ISO 6579 (2008b)], and research of Listeria monocytogenes [AFNOR BRD 07/4-09/98 (AFNOR, 2010a)]. Furthermore, the volunteer's knowledge on the correct hygienic procedures during the recovery was evaluated by the 71 questionnaires with the aim to prevent foodborne diseases. The results show that the recovery of surplus from catering service and their reuse at COs should be planned with correct procedures, and the volunteer's knowledge on the hygienic aspects appears to be a critical point. The recovery and the charitable activities require an appropriate assessment and careful risk analysis, in order to manage the complexity of no profit organization.

Features of Lactobacillus Sakei Isolated from Italian Sausages: Focus on Strains from Ventricina del Vastese

In this study bacterial isolates from Ventricina del Vastese sausage, previously identified as Lactobacillus (L.) sakei, were characterised genotypically, physiologically and on the basis of some technologically relevant traits. A total of 70 L. sakei isolates from sausages manufactured with spontaneous fermentation in the same producing plant were taken into account. Six genotypic groups were distinguished on the basis of Rep-polymerase chain reaction with the GTG₅ primer, some of which were found only in the sausages ripened at temperatures lower than 10°C for the first two months and lower than 16°C for the remaining three months, according to the traditional ripening process. Six strains were selected as representative of the genotypic profiles and further characterised. A high diversity in their fermentation profiles was observed, and different groups were separated on the basis of growth and acidifying capacity in meat extract. None of the strains produced histamine or tyramine in vitro. One strain was able to slightly inhibit Listeria (L.) monocytogenes and L. innocua and all six strains were able to slightly inhibit Enterobacteriaceae isolated from Ventricina del Vastese sausages in vitro. Results showed that most L. sakei strains can have a role in improving the safety of low acidity fermented sausages, even though a limited acidifying capacity was observed in a meat-like substrate, and that L. sakei strains able to produce biogenic amines are unlikely to occur in spontaneously fermented meat products.

Levels of Nitrates and Nitrites in Chili Pepper and Ventricina Salami

Ventricina is a traditional sausage made from pork meat produced in the Abruzzi and Molise regions. The aim of this study was to detect the content of nitrates and nitrites in local cultivars of chilli pepper, and their concentration in ventricina samples spiced with the same chilli pepper. Furthermore, it was examined whether, in the samples of ventricina with nitrate addition, the spicing with chilli pepper could exceed the maximum added dose. The concentration of nitrates and nitrites in the organic chilli pepper was 531.0±94.6 mg/kg and less than 5.0 mg, respectively, in the traditional chilli pepper it was 394.0±39.6 and less than 5.0 mg, while in the commercial it was 325.0±115.0 and less than 5.0 mg. The determination of nitrites and nitrates was carried out by high performance ion chromatography. In ventricina samples produced without added sodium nitrate, nitrates and nitrites were below 5.0 mg/kg at the case-filling time (t₀) and after 50 days of aging (t₅₀). In the samples of ventricina with added sodium nitrate, nitrate concentration values were 134.0±20.9 mg/kg at t₀ and 129.0±15.4 mg/kg at t₅₀, while the nitrites were below 5.0 mg/kg at t₀ and 28.8±15.8 mg/kg at t₅₀. Although in ventricina the amount of chilli pepper is quite relevant, it did not lead to a detectable concentration of nitrates. The maximum allowed amount was never exceeded.

[Leptospirosis: occupational risk in the chain of food of animal origin]

Leptospirosis is a worldwide zoonotic infection. The source of infection in humans is usually either direct or indirect contact with the urine of infected animals. Occupation is a significant risk factor for humans. Direct contact with infected animals accounts for most infections in farmers, veterinarians, abattoir workers, meat inspectors. The highest risk is associated with swine farming, slaughterhouse and meat industry workers. Most cases are diagnosed by serology. Leptospirosis may be prevented trought appropriate hygiene, sanitization, animal husbandry. It is essential to educate people working with animals or animal tissues about measures for reducing the risk of exposure to Leptospira. Protective clothing provided included an apron, gloves and rubber boots. When the risk is high, serologic testing are useful also.