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Staphylococcus aureus is one of the primary pathogenic agents found in cheeses produced with raw milk. Some strains of S. aureus are enterotoxigenic, possessing the ability to produce toxins responsible for staphylococcal food poisoning when present in contaminated foods. This study aimed to genotypically characterize, assess the antimicrobial resistance profile, and examine the enterotoxigenic potential of strains of S. aureus isolated from artisanal colonial cheese. Additionally, a bacterial diversity assessment in the cheeses was conducted by sequencing the 16S rRNA gene. The metataxomic profile revealed the presence of 68 distinct species in the cheese samples. Fifty-seven isolates of S. aureus were identified, with highlighted resistance to penicillin in 33% of the isolates, followed by clindamycin (28%), erythromycin (26%), and tetracycline (23%). The evaluated strains also exhibited inducible resistance to clindamycin, with nine isolates considered multidrug-resistant (MDR). The agr type I was the most prevalent (62%) among the isolates, followed by agr type II (24%). Additionally, ten spa types were identified. Although no enterotoxins and their associated genes were detected in the samples and isolates, respectively, the Panton-Valentine leukocidin gene (lukS-lukF) was found in 39% of the isolates. The presence of MDR pathogens in the artisanal raw milk cheese production chain underscores the need for quality management to prevent the contamination and dissemination of S. aureus strains.

Research into microbial interactions during coffee processing is essential for developing new methods that adapt to climate change and improve flavor, thus enhancing the resilience and quality of global coffee production. This study aimed to investigate how microbial communities interact and contribute to flavor development in coffee processing within humid subtropical climates. Employing Illumina sequencing for microbial dynamics analysis, and high-performance liquid chromatography (HPLC) integrated with gas chromatography–mass spectrometry (GC-MS) for metabolite assessment, the study revealed intricate microbial diversity and associated metabolic activities. Throughout the fermentation process, dominant microbial species included Enterobacter, Erwinia, Kluyvera, and Pantoea from the prokaryotic group, and Fusarium, Cladosporium, Kurtzmaniella, Leptosphaerulina, Neonectria, and Penicillium from the eukaryotic group. The key metabolites identified were ethanol, and lactic, acetic, and citric acids. Notably, the bacterial community plays a crucial role in flavor development by utilizing metabolic versatility to produce esters and alcohols, while plant-derived metabolites such as caffeine and linalool remain stable throughout the fermentation process. The undirected network analysis revealed 321 interactions among microbial species and key substances during the fermentation process, with Enterobacter, Kluyvera, and Serratia showing strong connections with sugar and various volatile compounds, such as hexanal, benzaldehyde, 3-methylbenzaldehyde, 2-butenal, and 4-heptenal. These interactions, including inhibitory effects by Fusarium and Cladosporium, suggest microbial adaptability to subtropical conditions, potentially influencing fermentation and coffee quality. The sensory analysis showed that the final beverage obtained a score of 80.83 ± 0.39, being classified as a specialty coffee by the Specialty Coffee Association (SCA) metrics. Nonetheless, further enhancements in acidity, body, and aftertaste could lead to a more balanced flavor profile. The findings of this research hold substantial implications for the coffee industry in humid subtropical regions, offering potential strategies to enhance flavor quality and consistency through controlled fermentation practices. Furthermore, this study contributes to the broader understanding of how microbial ecology interplays with environmental factors to influence food and beverage fermentation, a topic of growing interest in the context of climate change and sustainable agriculture.

This study evaluated the results recorded at the Central Public Health Laboratory of Santa Catarina state (Brazil) concerning the investigation of Rotavirus (RVA) and Norovirus (NoVs) – genogroups GI and GII. Samples were taken from seawater, river water, estuary water, lagoon water, and treated water samples, from 2018 to 2021. The aim was to correlate them with each other and evaluate their association with the type of water, presence of shellfish farming, population density, and sewage treatment. The most prevalent enteric virus was RVA, followed by NoV GI and NoV GII. There was a strong correlation between the presence/absence of RVA and the presence/absence of at least one NoV genogroup, mainly in samples collected in rivers. No correlation was observed between the presence of any virus and the presence of shellfish farming. When evaluating the binomial sewage treatment vs. population density, the correlation coefficients between population density and the presence of the virus in a sample were higher than the coefficients between the percentage of treated sewage and the presence of the virus. Sources of human-origin pollution impair the quality of treated and surface waters, and therefore the results of this work can help develop viral-monitoring programs in these places. HIGHLIGHTS Rotavirus (RVA) and Norovirus GI and GII (NoVs) were present in 42 and 44% of the analyzed samples, respectively.; The most prevalent virus was RVA (42.3%), followed by NoV GI (22.90%) and NoV GII (22.3%).; No association was observed between the presence of RVA and NoVs and the presence of shellfish farming.; An association between population density, treated sewage, and the presence of RVA and NoVs was observed.;

ABSTRACT: More than 30 types of artisanal cheeses are known in Brazil; however, microorganisms, such as Staphylococcus spp., can contaminate raw milk cheeses through different sources, from milking to processing. Staphylococcal food poisoning results from the consumption of food in which coagulase-positive staphylococci, mostly Staphylococcus aureus, have developed and produced enterotoxins. In addition, an emerging public health concern is the increasing antimicrobial resistance of some Staphylococcus strains. Furthermore, the ability of Staphylococcus spp. in sharing antibiotic resistance-related genes with other bacteria increases this problem. In light of these observations, this review aims to discuss the presence of, enterotoxins of, and antibiotic-resistant of Staphylococcus spp. in Brazilian artisanal cheese produced with raw milk.

This study evaluated the effect of fermentation with Lactobacillus acidophilus on the biochemical and nutritional compositions of a plant-based diet and its effects on the productive performance and intestinal health of juvenile Nile tilapia (Oreochromis niloticus) reared in a biofloc technology (BFT) system. The in vitro kinetics of feed fermentation were studied to determine the L. acidophilus growth and acidification curve through counting the colony-forming units (CFUs) mL−1 and measuring the pH. Physicochemical and bromatological analyses of the feed were also performed. Based on the microbial growth kinetics results, vegetable-based Nile tilapia feeds fermented for 6 (FPB6) and 18 (FPB18) h were evaluated for 60 days. Fermented diets were compared with a positive control diet containing fishmeal (CFM) and a negative control diet without animal protein (CPB). Fermentation with L. acidophilus increased lactic acid bacteria (LAB) count and the soluble protein concentration of the plant-based feed, as well as decreasing the pH (p < 0.05). FPB treatments improved fish survival compared with CPB (p < 0.05). Fermentation increased feed intake but worsened feed efficiency (p < 0.05). The use of fermented feeds increased the LAB count and reduced pathogenic bacteria both in the BFT system’s water and in the animals’ intestines (p < 0.05). Fermented plant-based feeds showed greater villi (FPB6; FPB18) and higher goblet cell (FPB6) counts relative to the non-fermented plant-based feed, which may indicate improved intestinal health. The results obtained in this study are promising and show the sustainable potential of using fermented plant-based feeds in fish feeding rather than animal protein and, in particular, fishmeal.

Irritable bowel syndrome (IBS) is a chronic condition that affects 11.2% of the world’s population. The management of gut microbiota using probiotic and synbiotic agents might be a valid alternative to assist in the treatment of IBS. The focus of this study was to evaluate the effects of prebiotic and synbiotic compounds carried by different foods on major symptoms of IBS through a systematic literature review. MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and LILACS were accessed during July 2021. The studies included in this review were the ones that tested volunteers older than 16 years of age and were conducted using a randomized, controlled clinical trial. The risk of bias was assessed by using the Cochrane risk-of-bias tool for randomized trials (RoB2). Furthermore, the data found were qualitatively evaluated due to the studies’ differences. Two papers were able to fit the criteria, with a total sample size of 280 participants. No datum was found regarding the use of prebiotics in the treatment of IBS. Synbiotic agents, however, had a positive effect on gastrointestinal symptoms and the participants’ overall bowel satisfaction; however, it was not possible to reach a consensus on which effects. Further studies regarding the use of synbiotics and prebiotics must be carried out to determine which effects are the most significant in the treatment of IBS.

In recent years, the development of non-dairy probiotic beverages has been stimulated due to the increase in the number of people with milk protein allergies, lactose intolerance, and those that are vegetarian and vegan eating. These functional foods have a number of health benefits, combining properties of plant matrices and probiotic effects. However, a major challenge in formulating these beverages is the limited number of adapted microbial strains with probiotic phenotype that promote desirable sensory characteristics, besides remaining viable in the final product for long periods. Therefore, this review aimed to provide an overview of the production of traditional non-dairy fermented beverages produced in the world and to show the biotechnological potential of these foods as a source of strains presenting a probiotic phenotype. In addition, the latest developments on the role of lactic acid bacteria, Bifidobacterium, and yeast species in the development of new probiotic beverages from the fermentation of fruit and cereal are discussed. Finally, some aspects related to food safety issues are shown.

ABSTRACT Conjugated linoleic acid (CLA) has been the subject of numerous studies in recent decades because of its associated health benefits. CLA is an intermediate product of the biohydrogenation pathway of linoleic acid (LA) in bacteria. Several bacterial species capable of efficiently converting LA into CLA have been widely reported in the literature, among them Lactobacillus delbrueckii subsp. bulgaricus LBP UFSC 2230. Over the last few years, a multicomponent enzymatic system consisting of three enzymes involved in the biohydrogenation process of LA has been proposed. Sequencing the genome of L. delbrueckii subsp. bulgaricus LBP UFSC 2230 revealed only one gene capable of encoding an oleate hydratase (OleH), unlike the presence of multiple genes typically found in similar strains. This study investigated the biological effect of the OleH enzyme of L. delbrueckii subsp. bulgaricus LBP UFSC 2230 on the hydration of LA and dehydration of ricinoleic acid (RA) and its possible role in the production of CLA. The OleH was cloned, expressed, purified, and characterized. Fatty acid measurements were made by an internal standard method using a gas chromatography-coupled flame ionization detector (GC-FID) system. It was found that the enzyme is a hydratase/dehydratase, leading to a reversible transformation between LA and RA. In addition, the results showed that L. delbrueckii subsp. bulgaricus LBP UFSC 2230 OleH protein plays a role in stress tolerance in Escherichia coli. In conclusion, the OleH of L. delbrueckii subsp. bulgaricus LBP UFSC 2230 catalyzes the initial stage of saturation metabolism of LA, although it has not converted the substrates directly into CLA. IMPORTANCE This study provides insight into the enzymatic mechanism of CLA synthesis in L. delbrueckii subsp. bulgaricus and broadens our understanding of the bioconversion of LA and RA by OleH. The impact of OleH on the production of the c9, t11 CLA isomer and stress tolerance by E. coli has been assisted. The results provide an understanding of the factors which influence OleH activity. L. delbrueckii subsp. bulgaricus LBP UFSC 2230 OleH presented two putative fatty acid-binding sites. Recombinant OleH catalyzed both LA hydration and RA dehydration. OleH was shown to play a role in bacterial growth performance in the presence of LA.

The use of yeasts as starter cultures was boosted with the emergence of large-scale fermentations in the 20th century. Since then, Saccharomyces cerevisiae has been the most common and widely used microorganism in the food industry. However, Candida species have also been used as an adjuvant in cheese production or as starters for coffee, cocoa, vegetable, meat, beer, and wine fermentations. A thorough screening of candidate Candida is sometimes performed to obtain the best performing strains to enhance specific features. Some commonly selected species include C. pulcherrima (teleomorph Metschnikowia pulcherrima) (wine), C. parapsilosis (teleomorph Monilia parapsilosis) (coffee), C. famata (teleomorph Debaryomyces hansenii) (cheese), and C. zeylanoides (teleomorph Kurtzmaniella zeylanoides) and C. norvegensis (teleomorph Pichia norvegensis) (cocoa). These species are associated with the production of key metabolites (food aroma formation) and different enzymes. However, safety-associated selection criteria are often neglected. It is widely known that some Candida species are opportunistic human pathogens, with important clinical relevance. Here, the physiology and metabolism of Candida species are addressed, initially emphasizing their clinical aspects and potential pathogenicity. Then, Candida species used in food fermentations and their functional roles are reported. We recommended that Candida not be used as food cultures if safety assessments are not performed. Some safety features are highlighted to help researchers choose methods and selection criteria.

Food fermentation has been used for thousands of years for food preservation [...]

The effect of high-pressure carbon dioxide processing on inactivation of aerobic mesophilic bacteria and Escherichia coli ATCC 25922 inoculated in human milk was investigated. The effect of the ratio between sample mass and CO2 (1:0.2; 1:0.6 and 1:1 m/m); depressurization rate (1, 5.5 and 10 MPa/min); and pressure cycling (1, 3 and 5) were the process variables studied. The best reductions in aerobic mesophilic bacteria as well as in E. coli (>6.0 and >5.0 log, respectively) were obtained with a ratio of 1:1, a depressurization rate of 10 MPa/min, and one cycle of pressurization/depressurization. The depressurization rate was found to be an important variable in the inactivation process. The results suggest that high-pressure carbon dioxide processing can be applied to human milk as a safe alternative to the pasteurization employed in human milk banks.

Microbial fermentation plays an important role in the manufacturing of artisanal sausages and can have major effects on product quality and safety. We used metagenomics and culture-dependent methods to study the presence of Hepatitis E virus (HEV) and Rotavirus-A (RV-A), and fungal and bacterial communities, in artisanal Colonial salami-type dry-fermented sausages in Santa Catarina state, Brazil. Lactic acid bacteria (LAB) and yeast dominated the microbiome. Latilactobacillus sakei and Debaryomyces hansenii were ubiquitous and the most abundant species. The DNA of some foodborne pathogens was found in very low concentrations although viable cells of most of these species were undetectable by cultivation methods. The characteristics of the raw material and hygiene of the artisanal sausage manufacturing process resulted in high loads of beneficial microorganisms and the absence of HEV and RV-A viruses as determined by RT-qPCR assays. In conclusion, high LAB load in sausages was more relevant to preventing pathogen growth than the ripening time and/or physicochemical characteristics. However, the presence of Clostridium spp. and other pathogens in some samples must be taken into account for the development of future preservation methods; appropriate LAB starter cultures and health surveillance are required in the production process to prevent foodborne outbreaks.

Hepatitis E virus (HEV) is an important enteric agent that can circulate in swine; it is excreted in manure, and of zoonotic interest. The present study investigated, by RT-qPCR, the circulation of HEV in swine manure from different types of pig farms (maternity, nursery, and grow-finish farms) in Santa Catarina State, the major pig production area of Brazil, and also evaluated the HEV removal efficiency of psychrophilic anaerobic biodigesters (PABs). While HEV was consistently detected in manure from grow-finish pig farms (>4 log HEV genome copies (GC) L−1), the virus was not detected in manure from maternity and nursery farms. These findings suggest a potential high biosafety status during primary-swine production, with a subsequent contamination in grow-finish production. The anaerobic biodigestion process reduced more than 2 log10 HEV GC in the processed swine manure. However, the virus concentration in final effluent remained high, with an average value of 3.85 log10 HEV GC L−1. Consequently, our results demonstrate that PABs can be a robust tool for effective inactivation of HEV, while reinforcing the need for sanitary surveillance and legislation of swine manure-derived biofertilizers, to avoid the spread of zoonotic enteric pathogens such as HEV.

Background: Fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAPs) are an heterogeneous group of compounds that can be poorly digested and may have a range of effects on gastrointestinal processes. FODMAPs are found in a wide variety of foods, including bread. FODMAPs’ intake is associated with the onset of symptoms of irritable bowel syndrome (IBS). On the other hand, some FODMAPs contribute to the healthy maintenance of intestinal microbiota. Volume increase of bread dough commonly relies on the use of two biological leavening agents, sourdough and baker’s yeast and, in some cases, a combination of both.Scope and Approach: The main objective of this review is to discuss the association between FODMAPs and IBS, beneficial effects of FODMAPs on healthy subjects and potential impact of biological leavening agents on FODMAPs content of bread.Key Findings and Conclusion: Given that yeasts and lactic acid bacteria, the dominant microorganisms in sourdough, may degrade FODMAPs, it would be possible to modulate the FODMAPs concentration in bread, thus positively affecting consumers’ health.

Coconut water is a liquid obtained from coconuts (Cocos nucifera L.) with natural hydrating qualities, functional health properties and nutritional benefits. The aim of this work was to develop an innovative, non-dairy, fermented functional beverage using coconut water as the main ingredient for providing the intrinsic health properties. Among seven autochthonous lactic acid bacteria strains isolated from natural fermentation of coconut water, Lactobacillus plantarum was selected due to its inhibitory activity against some pathogens and its characteristics that favor survival under some technological and gastrointestinal conditions. The fermentation was carried out for 8 h at 37 °C in the presence of yeast extract, soy protein hydrolysate and sucrose. Coconut water is a non-dairy substrate that can be introduced as a new vehicle for the consumption of functional cultured beverage, especially by vegans and/or vegetarians and lactose intolerant consumers.

Functional foods are defined as those that provide additional benefits to consumers. The market for foods with functional properties is expanding, supported by scientific evidences, which leads the developing of different special foods. This market segment is related to the innovations, as well as the traditional functional dairy and non dairy products, gain traction in the marketplace for innovative products like based whey sports beverage. Besides the functionality of muscle protein synthesis, these beverages are entering into areas such as clinical nutrition and satiety. Thus, it can be supposed that the composition and technological versatility of the whey support the use as innovative ingredient for foods and beverages. This review aim to supply an overview about functional foods, mainly the segment of whey based beverages. The success of this new nutritional approach is close related to the requirement to identify, to characterize and to develop methodologies to measure and to validate more precisely the relevant functional markers, making them open for a public domain.Alimentos funcionais são definidos como aqueles que fornecem benefícios adicionais aos da alimentação. O mercado de alimentos com propriedades funcionais está em crescente expansão, apoiado por evidências científicas, que creditam o desenvolvimento de alimentos diferenciados. Esse segmento está relacionado às inovações, pois além dos tradicionais produtos funcionais lácteos e não lácteos, ganham espaço no mercado produtos inovadores como bebidas especiais para esportistas a base de soro de leite. Além da funcionalidade sobre a síntese protéica muscular, estas bebidas protéicas estão se inserindo em áreas como a da saciedade e da nutrição clínica. Assim, é possível afirmar que o soro de leite se diferencia como ingrediente de inovação em alimentos e bebidas, porque demonstra uma grande versatilidade tecnológica. Esta revisão objetiva fornecer uma visão geral sobre alimentos funcionais, enfatizando o segmento de bebidas a base de soro de leite. O sucesso desta nova abordagem nutricional está intimamente ligado à necessidade de identificar, caracterizar e desenvolver metodologias para medir e validar com maior precisão os relevantes marcadores funcionais, tornando-os de domínio público, além, é claro, da aceitação por parte do consumidor.

Colostrum is the first milk produced by the mammary gland during the early postpartum period. In addition to nutrients, antimicrobial and growth factors, bovine colostrum contains valuable microflora, including members of the genera Lactobacillus and Bifidobacterium, which have been used widely in probiotic food. The aim of this work is to identify and quantify the microflora of colostrum samples from two Holstein dairy cows on the first three postpartum days through culture-dependent 16S rRNA gene sequencing and length heterogeneity polymerase chain reaction (LH-PCR) techniques, using an adapted method to extract the total DNA. Twenty-nine strains isolated in synthetic media were identified by their 16S rRNA gene sequences, revealing two potential probiotic strains (Lactobacillus casei and Bifidobacterium pseudolongum). Colostrum samples were subjected to LH-PCR analysis to obtain fingerprint profiles of the microflora. Lactobacillus casei was the main species present in the samples. The probiotic potential of these bacteria for use in fermented and functional foods remains to be evaluated.

Probiotics, live cells with different beneficiary characteristics, have been extensivelly studied and explored commercially in many different products in the world. Their benefits to human and animal health have been proven in hundreds of scientific research. Lactobacillus and Bifidobacterium are the main probiotic groups; however, there are reports on the probiotic potential of Pediococcus, Lactococcus, Bacillus and yeasts. Some of the identified probiotic strains exhibit powerful anti-inflammatory, antiallergic and other important properties. Apart from that, the consumption of dairy and non-dairy products stimulates the immunity in different ways. Various food matrices have been used with probiotics, which are briefly documented. In this review, the history of probiotics, their application in the health and food areas and new trends in probiotic products and processes are presented.

Conjugated linoleic acid (CLA) isomers have attracted significant attention due to their important physiological properties, which have been observed in humans. Many lactic acid bacteria (LAB) demonstrate the ability to produce CLA isomers (C18:2 cis-9, trans-11 and C18:2 trans-10, cis-12) from the linoleic acid (LA) present in milk or in synthetic media. CLA isomers can be synthesized in vitro by LAB using vegetable oils rich in LA. The aim of this review is to present an update on the studies that have been conducted on the production of CLA isomers from LA mainly by LAB and of the factors that influence this conversion (source and concentration of LA and fermentation conditions). In addition, this review presents the relationship between the consumption of CLA isomers and their health benefits in humans such as anti-atherosclerosis and anti-carcinogenic effects. There is considerable variation between the studies concerning the beneficial effects of CLA in animal models, which have not been reflected in human studies. This can be attributed to the differences in the doses of CLA isomers used and to the different sources of CLA. Furthermore, the regulatory and scientific information classifying the physiological properties of CLA, which serve as support for the claims of its potential as a functional ingredient, are presented. More research is needed to determine whether CLA production by LAB can be enhanced and to determine the optimal requirements for these microbial cultures. Furthermore, safety and efficacy of CLA consumption have to be investigated in the future.