Lacto-fermented garlic handcrafted in the Lower Silesia Region (Poland): Microbial diversity, morpho-textural traits, and volatile compounds.

The aim of the present study was to provide a first characterization of lacto-fermented garlic manufactured by local small-scale artisanal producers in the Lower Silesia Region (Poland). The lacto-fermented garlic samples showed high nutritional features in terms of antioxidant activity. A total of 86 compounds, belonging to various chemical classes, were identified by headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC/MS). Most of these compounds belonged to six main classes, being sulfur compounds, esters and acetates, oxygenated monoterpenes, monoterpene hydrocarbons, and alcohols. Aldehydes, acids, ketones, furans, and phenols were also identified. In the analyzed samples, counts up to 8 log cfu g-1 were observed for lactic acid bacteria. Metataxonomic analysis revealed the presence of Levilactobacillus, Lactiplantibacillus, Latilactobacillus, Secundilactobacillus, Weissella, Leuconostoc, Lactococcus, Pediococcus, and Lacticaseibacillus among the major taxa. These results were confirmed by the isolation and characterization of viable lactic acid bacteria. Indeed, the presence of the closest relatives to Lacticaseibacillus casei group, Pediococcus parvulus, Levilactobacillus brevis, Levilactobacillus parabrevis, and Lactiplantibacillus plantarum group was observed. A good acidification performance in salty garlic-based medium was observed for all the isolates that, between 8 and 15 days of fermentation, reached pH values comprised between 4 and 3.5, depending on the tested species. Of note, 15 out of the 37 lactic acid bacteria isolates (Levilactobacillus parabrevis, Pediococcus parvulus, Lactiplantibacillus plantarum group, and Lacticaseibacillus casei group) showed the presence of the hdcA gene of Gram-positive bacteria encoding for histidine decarboxylase. Furthermore, for 8 out of the 37 isolates the in-vitro exopolysaccharides production was observed. No isolate showed inhibitory activity against the three Listeria innocua strains used as surrogate for Listeria monocytogenes.

Insect live larvae as a new nutritional model in duck: effects on gut health.

BACKGROUND: This study aimed to evaluate the effects of Hermetia illucens (Black soldier fly-BSF) and Tenebrio molitor (Yellow mealworm-YMW) live larvae as a new nutritional model on duck's gut health, considering gut histomorphometry, mucin composition, cytokines transcription levels, and microbiota. A total of 126, 3-days-old, females Muscovy ducks were randomly allotted to three dietary treatments (6 replicates/treatment, 7 birds/pen): (i) C: basal diet; (ii) BSF: C + BSF live larvae; (iii) YMW: C + YMW live larvae. BSF and YMW live larvae were administered on top of the basal diet, based on the 5% of the expected daily feed intake. The live weight, average daily gain, average daily feed intake and feed conversion ratio were evaluated for the whole experimental period. On day 52, 12 ducks/treatment (2 birds/replicate) were slaughtered and samples of duodenum, jejunum, ileum, spleen, liver, thymus and bursa of Fabricius were collected for histomorphometry. Mucin composition was evaluated in the small intestine through histochemical staining while jejunal MUC-2 and cytokines transcription levels were evaluated by rt-qPCR. Cecal microbiota was also analyzed by means of 16 S rRNA gene sequencing. RESULTS: Birds' growth performance and histomorphometry were not influenced by diet, with a proximo-distal decreasing gradient from duodenum to ileum (p < 0.001), respecting the physiological gut development. Mucin staining intensity and MUC-2 gene expression did not vary among dietary treatments, even though mucin intensity increased from duodenum to ileum, according to normal gut mucus physiology (p < 0.001). Regarding local immune response, IL-6 was higher in YMW group when compared to the other groups (p = 0.009). Insect live larvae did not affect cecal microbiota diversity, but BSF and YMW groups showed a higher presence of Helicobacter, Elusimicrobium, and Succinatimonas and a lower abundance of Coriobacteriaceae and Phascolarctobacterium compared to C birds (p < 0.05). CONCLUSIONS: The use of BSF and YMW live larvae as new nutritional model did not impair gut development and mucin composition of Muscovy ducks, but slightly improved the intestinal immune status and the microbiota composition by enhancing regulatory cytokine IL-6 and by increasing minor Operational Taxonomic Units (OTUs) involved in short-chain fatty acids production.

Microbiota characterization throughout the digestive tract of horses fed a high-fiber vs. a high-starch diet.

Introduction: Diet is one of the main factors influencing the intestinal microbiota in horses, yet a systematic characterization of the microbiota along the length of the digestive tract in clinically healthy horses, homogenous for age and breed and receiving a specific diet is lacking. Methods: The study used 16S rRNA amplicon sequencing to characterize the microbiota of the intestinal tracts of 19 healthy Bardigiano horses of 14.3 ± 0.7 months of age fed one of two diets. Nine horses received a high-starch diet (HS), and ten horses received a high-fiber diet (HF). After 129 days, the horses were slaughtered, and samples were collected from the different intestinal tract compartments. Results and discussion: The microbiota alpha diversity indices were lower in the caecum, pelvic flexure and right dorsal colon of the horses fed the HS diet (False Discovery Rate, FDR < 0.05). The values of beta diversity indicated significant compositional differences between the studied intestinal tract compartments according to the diet received (FDR < 0.05). At the lower taxonomic level (genus or family), the HS diet was associated with a higher relative frequency of Enterobacteriaceae within the small intestine (jejunum and duodenum) (FDR < 0.05). Within the hindgut (caecum and sternal flexure), the HS diet was associated with lower relative frequencies (i.e., a smaller core community) of bacteria belonging to Fibrobacteraceae and Prevotellaceae (FDR < 0.05). Moreover, horses fed the HS diet displayed a higher relative abundance of Streptococcus in the caecum (FDR < 0.05) and Fusobacterium in the sternal flexure (FDR < 0.05), both of which are pathogenic bacteria responsible for inflammation diseases. Samples collected from the pelvic flexure and rectum of horses fed the HS diet showed significantly higher relative frequencies of Succinivibrionaceae (FDR < 0.05) - amylolytic bacteria associated with acidosis. The relative frequencies of the Lachnospiraceae and Ruminococcaceae were lower in the feces collected from the rectum of horses receiving the HS diet vs. HF diet, indicating smaller core communities of these bacteria (FDR < 0.05). Fibrous diets should be promoted to prevent dysbiosis of the microbiota associated with high-starch diet.

Microbial contamination pathways in a poultry abattoir provided clues on the distribution and persistence of Arcobacter spp.

The consumption of contaminated poultry meat is a significant threat for public health, as it implicates in foodborne pathogen infections, such as those caused by Arcobacter. The mitigation of clinical cases requires the understanding of contamination pathways in each food process and the characterization of resident microbiota in the productive environments, so that targeted sanitizing procedures can be effectively implemented. Nowadays these investigations can benefit from the complementary and thoughtful use of culture- and omics-based analyses, although their application in situ is still limited. Therefore, the 16S-rRNA gene-based sequencing of total DNA and the targeted isolation of Arcobacter spp. through enrichment were performed to reconstruct the environmental contamination pathways within a poultry abattoir, as well as the dynamics and distribution of this emerging pathogen. To that scope, broiler's neck skin and caeca have been sampled during processing, while environmental swabs were collected from surfaces after cleaning and sanitizing. Metataxonomic survey highlighted a negligible impact of fecal contamination and a major role of broiler's skin in determining the composition of the resident abattoir microbiota. The introduction of Arcobacter spp. in the environment was mainly conveyed by this source rather than the intestinal content. Arcobacter butzleri represented one of the most abundant species and was extensively detected in the abattoir by both metataxonomic and enrichment methods, showing higher prevalence than other more thermophilic Campylobacterota. In particular, Arcobacter spp. was recovered viable in the plucking sector with high frequency, despite the adequacy of the sanitizing procedure.IMPORTANCEOur findings have emphasized the persistence of Arcobacter spp. in a modern poultry abattoir and its establishment as part of the resident microbiota in specific environmental niches. Although the responses provided here are not conclusive for the identification of the primary source of contamination, this biogeographic assessment underscores the importance of monitoring Arcobacter spp. from the early stages of the production chain with the integrative support of metataxonomic analysis. Through such combined detection approaches, the presence of this pathogen could be soon regarded as hallmark indicator of food safety and quality in poultry slaughtering.

Monitoring the yeasts ecology and volatiles profile throughout the spontaneous fermentation of Taggiasca cv. table olives through culture-dependent and independent methods.

Taggiasca table olives are typical of Liguria, a Northwestern Italian region, produced with a spontaneous fermentation carried out by placing the raw drupes directly into brine with a salt concentration of 8-12 % w/v. Such concentrations limit the development of unwanted microbes and favor the growth of yeasts. This process usually lasts up to 8 months. Yeasts are found throughout the entire fermentation process and they are mainly involved in the production of volatile organic compounds, which strongly impact the quality of the final product. The aim of this study was to evaluate the dynamics of autochthonous yeasts in brines and olives in a spontaneous process with no lye pre-treatment or addition of acids in the fermenting brine with 10 % NaCl (w/v) in two batches during 2021 harvest. Three hundred seventy-three yeast colonies were isolated, characterized by rep-PCR and identified by the D1/D2 region of the 26S rRNA gene sequencing. Mycobiota was also studied by 26S rRNA gene metataxonomics, while metabolome was assessed through GC-MS analysis. Traditional culture-dependent methods showed the dominance of Candida diddensiae, Wickerhamomyces anomalus, Pichia membranifaciens and Aureobasidium pullulans, with differences in species distribution between batches, sampling time and type of sample (olives/brines). Amplicon-based sequencing confirmed the dominance of W. anomalus in batch 1 throughout the entire fermentation, while Cyteromyces nyonsensis and Aureobasidium spp. were most abundant in the fermentation in batch 2. Volatilome results were analyzed and correlated to the mycobiota data, confirming differences between fermentation stages. Given the high appreciation for this traditional food, this study helps elucidate the mycobiota associated to Taggiasca cv. table olives and its relationship with the quality of the final product.

Spontaneous fermentation of Marastina wines: The correlation between autochthonous mycobiota and phenolic compounds.

Understanding fungal community dynamics during fermentation is important for assessing their influence on wine's phenolic content. The present study represents the first effort to explore the correlation between the autochthonous mycobiota of Marastina grapes collected from Dalmatian winegrowing sub-regions in Croatia and the phenolic composition, as well as the physicochemical parameters of wines produced through spontaneous fermentation. The metataxonomic approach revealed Metschnikowia pulcherrima, Metschnikowia fructicola and Hanseniaspora uvarum as the core mycobiota detected at the initial phase of fermentation. By contrast, Saccharomyces cerevisiae took over the dominance starting from the middle stage of fermentation. The wine's phenolic compounds were revealed by high-performance liquid chromatography, with tyrosol being the most abundant. Rhodotorula babjevae and Botrytis cinerea showed a positive correlation with p-hydroxybenzoic acid, gentisic acid, caffeic acid and cinnamic acid, while demonstrating a negative correlation with protocatechuic acid and chlorogenic acid. Heterophoma novae-verbascicola exhibited the opposite behaviour regarding the same phenolic compounds. The concentration of lactic acid was positively correlated with B. cinerea and negatively correlated with Het. novae-verbascicola. These findings serve as a foundation for in-depth investigations into the role of autochthonous grape mycobiota in phenolic transformation during spontaneous fermentation, potentially leading to the production of high-quality wines with unique terroir characteristics. Future studies should aim to explore the specific role played by individual yeast isolates in the formation of phenolic compounds.

Tasting of traditional Polish fermented cucumbers: Microbiology, morpho-textural features, and volatilome.

In the present study, naturally fermented and unpasteurized cucumbers (Cucumis sativus L.) collected from 4 producers located in different regions of Poland were studied. The fermented cucumbers were characterized by significant nutritional features in terms of polyphenols content and antioxidant activity. Microbiological analyses revealed active bacterial populations of lactococci, thermophilic cocci, lactobacilli, and coagulase-negative cocci. The microbiological characterization of cucumber and brine samples through metataxonomic analysis allowed the dominant species to be detected, being Lactococcus and Streptococcus in cucumbers, and Lactiplantibacillus, Leuconostoc, Pediococcus, Secundilactobacillus, and Lentilactobacillus in brine. The isolation activity offered a clear picture of the main active lactic acid bacteria at the end of fermentation, being Pediococcus parvulus and Lactiplantibacillus plantarum group. All the studied isolates showed a good attitude in fermenting a cucumber-based broth, thus suggesting their potential application as starter or adjunct cultures for guided cucumber fermentation. Moreover, for the same isolates, strong aminopeptidase activity (due to leucine arylamidase and valine arylamidase) was observed, with potential effect on the definition of the final sensory traits of the product. Only a few isolates showed the ability to produce exopolysaccharides in synthetic medium. Of note, the presence of the hdcA gene in some Pediococcus ethanolidurans isolates also confirmed the need for a thorough characterization of starter candidates to avoid undesired adverse effects on consumer's health. No isolate showed the production of bacteriocins against Listeria innocua used as surrogate for Listeria monocytogenes. Based on the results of Headspace Solid-Phase Microextraction-Gas Chromatography/Mass Spectrometry analysis, a rich and complex volatilome, composed by more than 80 VOCs, was recognized and characterized. In more detail, the detected compounds belonged to 9 main classes, being oxygenated terpenes, alcohols, terpenes, ketones, acids, aldehydes, esters, sulfur, and sesquiterpenes.

Spotlight on autochthonous microbiota, morpho-textural characteristics, and volatilome of a traditional Polish cold-smoked raw sausage.

The aim of the present study was to obtain information on the bacterial diversity of traditional Polish cold-smoked raw sausages (Kielbasa polska wedzona) manufactured by two artisanal producers using different selective growth media and a metataxonomic analysis. Physico-chemical and morpho-textural characteristics were also carried out, together with Microextraction-Gas Chromatography/Mass Spectrometry (HS-SPMEGC/MS) to study the volatile organic compounds (VOCs). The results overall obtained allowed a picture of the microbiota, the morpho-textural characteristics, and the volatilome of traditional Polish cold-smoked raw sausages (Kielbasa polska wedzona) to be drawn for the first time. In more detail, viable counting revealed active populations of presumptive lactobacilli, enterococci, coagulase-negative cocci, and a few spoilage microorganisms typically occurring in raw meat products. The metataxonomic analysis revealed the dominance of Latilactobacillus sakei occurring with a relative frequency between 77% and 89%. Pediococcus pentosaceus, Weissella hellenica, and Leuconostoc carnosum were detected among the minority taxa. In the sausages herein studied, no histamine levels of concern were detected. The Principal Component Analysis (PCA) performed on the Amplicon Sequence Variants (ASVs) did not show significant differences in the microbiota composition among producers. The HS-SPMEGC/MS analysis allowed the detection and identification of more than 90 volatile components belonging to ten main classes, namely: aldehydes, ketones, esters and acetates, acids, alcohols, phenols, furans, sulphur compounds, terpenoids, and benzene derivatives. The detected VOCs originated from spices, smoke, and microbial metabolism. The PCA of volatile compounds allowed differences between the sausage samples of the two producers to be identified.

Chemical, microbiological, textural, and sensory characteristics of pilot-scale Caciofiore cheese curdled with commercial Cynara cardunculus rennet and crude extracts from spontaneous and cultivated Onopordum tauricum.

The aim of this study was the chemical, microbiological, textural, and sensory characterization of pilot-scale prototypes of an Italian ewe's raw milk cheese (Caciofiore) curdled with commercial Cynara cardunculus rennet, used as a control, and crude extracts obtained from flowers of either spontaneous or cultivated Onopordum tauricum. Hence, the control and experimental cheese prototypes produced in two rounds of cheesemaking trials were assayed, at the end of their 60-day maturation, for the following features: pH, titratable acidity, dry matter, fat, total and soluble nitrogen (TN and SN, respectively), ash, salt, protein, lactose, viable plate counts and composition of the bacterial and fungal populations, color, texture, volatile organic compounds (VOCs), and olfactory attributes by sensory analysis (the latter for the sole prototypes curdled with the commercial rennet and the extract obtained from cultivated O. tauricum). The data overall collected showed a very low impact of the type of thistle rennet on the analyzed cheese traits, with significant differences being exclusively found for SN/TN%, titratable acidity, color, and adhesiveness. By contrast, a higher impact of the cheesemaking round was seen, with significant differences being observed for salt content, load of presumptive lactobacilli, thermophilic cocci, and Escherichia coli, and levels of the following VOCs: 2,3-butanedione, 2-pentanone, 1-butanol, 2-heptanone, 3-methyl-1-butanol, 2-heptanol, 2-nonanone, dimethyl trisulfide, 2-methyl propanoic acid, butanoic acid, and 3-methyl butanoic acid. Sensory analysis revealed a strong ewe's cheese odor, accompanied by other olfactory notes, such as pungent, sour curd, sweet, and Parmesan cheese-like notes, in all the analysed cheese prototypes. Moreover, key odor active compounds, including butanoic acid, ethyl butanoate, 2,3-butanedione, 1-octen-3-one, and dimethyl trisulfide, were identified by GC-olfactometry analysis. Regarding the odor attributes as determined by sensory analysis, again the type of rennet had an almost negligible impact, with significant differences being only perceived for 1 or 2 out of 20 odor attributes, depending on the analytical conditions applied. Although some aspects deserve further investigation, the results herein collected confirm that O. tauricum can be regarded as an alternative source of thistle rennet for the manufacture of Caciofiore cheese, and more in general, Mediterranean ewe's milk cheeses.

Impact of Different Drying Methods on the Microbiota, Volatilome, Color, and Sensory Traits of Sea Fennel (Crithmum maritimum L.) Leaves.

Sea fennel (Crithmum maritimum L.) is a strongly aromatic herb of the Apiaceae family, whose full exploitation by the modern food industry is of growing interest. This study aimed at investigating the microbiological quality, volatile profile, and sensory traits of sea fennel spices produced using room-temperature drying, oven drying, microwave drying, and freeze drying. All the assayed methods were able to remove moisture up until water activity values below 0.6 were reached; however, except for microwave drying, none of the assayed methods were effective in reducing the loads of contaminating microorganisms. The metataxonomic analysis highlighted the presence of phytopathogens and even human pathogens, including members of the genera Bacillus, Pseudomonas, Alternaria, and Cryptococcus. When compared to fresh leaves, dried leaves showed increased L* (lightness) and c* (chroma, saturation) values and reduced hue angle. Dried leaves were also characterized by decreased levels of terpene hydrocarbons and increased levels of aldehydes, alcohols, and esters. For the sensory test, the microwave-dried samples obtained the highest appreciation by the trained panel. Overall, the collected data indicated microwave drying as the best option for producing sea fennel spices with low microbial loads, brilliant green color, and high-quality sensory traits.

Lactiplantibacillus plantarum, lactiplantibacillus pentosus and inulin meal inclusion boost the metagenomic function of broiler chickens.

BACKGROUND: The inclusion of alternative ingredients in poultry feed is foreseen to impact poultry gut microbiota. New feeding strategies (probiotics/prebiotics) must be adopted to allow sustainable productions. Therefore, the current study aimed to use metagenomics approaches to determine how dietary inclusion of prebiotic (inulin) plus a multi-strain probiotic mixture of Lactiplantibacillus plantarum and Lactiplantibacillus pentosus affected microbiota composition and functions of the gastro-intestinal tract of the broilers during production. Fecal samples were collected at the beginning of the trial and after 5, 11 and 32 days for metataxonomic analysis. At the end of the trial, broilers were submitted to anatomo-pathological investigations and caecal content was subjected to volatilome analysis and DNAseq. RESULTS: Probiotic plus prebiotic inclusion did not significantly influence bird performance and did not produce histopathological alterations or changes in blood measurements, which indicates that the probiotic did not impair the overall health status of the birds. The multi-strain probiotic plus inulin inclusion in broilers increased the abundance of Blautia, Faecalibacterium and Lachnospiraceae and as a consequence an increased level of butyric acid was observed. In addition, the administration of probiotics plus inulin modified the gut microbiota composition also at strain level since probiotics alone or in combination with inulin select specific Faecalibacterium prausnitzi strain populations. The metagenomic analysis showed in probiotic plus prebiotic fed broilers a higher number of genes required for branched-chain amino acid biosynthesis belonging to selected F. prausnitzi strains, which are crucial in increasing immune function resistance to pathogens. In the presence of the probiotic/prebiotic a reduction in the occurrence of antibiotic resistance genes belonging to aminoglycoside, beta-lactamase and lincosamide family was observed. CONCLUSIONS: The positive microbiome modulation observed is particularly relevant, since the use of these alternative ingredients could promote a healthier status of the broiler's gut.

Evaluation of the biofilm-forming ability and molecular characterization of dairy Bacillus spp. isolates.

Food processing lines represents a suitable environment for bacterial biofilm formation. One of the most common biofilm-forming genera in dairy processing plants is Bacillus, which includes species that may have a negative impact on safety and/or quality of dairy products. In the current study, we evaluated the biofilm forming ability and molecular characteristics of dairy Bacillus spp. isolates (B. cereus and B. subtilis). Reference strains (B. cereus ATCC 14579 and B. subtilis NCTC 3610) were also included in the experiment. All isolates were screened by micro-titer plate (96 wells) to assess their ability to form biofilm. Then, they were tested on two common food contact surfaces (polystyrene and stainless steel) by using 6-well plates and AISI 316 stainless steel coupons. Biofilm formation, expressed as biofilm production index (BPI), was higher on polystyrene than stainless steel (except for B. cereus ATCC 14579). These observations were further confirmed by scanning electron microscopy, which allowed the microscopy observation of biofilm structure. Moreover, a possible correlation among total viable cell counts (CFU) and BPI was examined, as well as a connection among biofilm formation and bacterial cell hydrophobicity. Finally, whole genome sequencing was performed highlighting a genetic similarity among the strains belonging to the same species. The presence of selected genes involved in biofilm formation was also examined showing that strains with a greater presence of these genes were able to produce more biofilm in the tested materials. Additionally, for B. cereus strains enterotoxin genes were detected.

Knot formation and spread along the shoot stem in 13 olive cultivars inoculated with an indigenous pathobiome of 7 species of Pseudomonas including Pseudomonas savastanoi.

Olive knot is a widely spread disease among olive (Olea europaea L.) trees. Pseudomonas savastanoi pv. savastanoi is recognized as the primary causative agent of the disease however, recent evidence indicated that consortia of bacteria (pathobiome), may favor its development. Several factors are involved in the host-plant relationship and affect the intensity of the symptoms. Among these the presence of wounds, or damages to the plants' tissues may affect the intensity and propagation of the disease. It remains unknown whether or not bacteria move from an infected wound to another not infected one via shoot tissues. The present investigation focused on the susceptibility to olive knot of several cultivars after inoculating artificial wounds with selected Pseudomonas species, while spreading the disease from these to wounds on the same stem, that had not been purposefully inoculated. The pathobiome for the inoculum was prepared with 7 species of Pseudomonas (including Pseudomonas savastanoi pv. savastanoi), isolated from knot samples collected from two different, heavily infected olive orchards. The inoculation was done after the manual execution of 10 horizontal wounds on the stem of potted plants of 13 olive cultivars grown in the greenhouse. Only the lowest 5 wounds were inoculated. The inoculated wounds showed a maximum percentage of knots after 187 days. All 13 cultivars showed knots yet, the cultivar with the most severe disease level to Pseudomonas savastanoi pv. savastanoi was 'Rosciola colli Esini'. The metataxonomic analysis performed on the olive knots removed after 225 days confirmed the dominance of the inoculated species Pseudomonas savastanoi in all the assayed cultivars. The not inoculated wounds did not show the knot disease likely because the bacterium's inability to transmigrate from the inoculated wounds to the non-inoculated ones.

Effect of an Enteroprotective Complementary Feed on Faecal Markers of Inflammation and Intestinal Microbiota Composition in Weaning Puppies.

Weaning entails numerous modifications of the intestinal structure and microbiota composition, making puppies at high risk of sickness during this delicate life stage. The aim of this study was to investigate the effects of a four-week administration of a supplement composed of ultramicronised Palmitoylethanolamide, bovine colostrum and Bacillus subtilis (Normalia® Extra, Innovet Italia Srl, Saccolongo, Italy) on markers of gut health and microbiome of weaning puppies. Twenty-nine four-week-old Golden Retriever puppies were randomly assigned to control (CG, n = 13) and treated (TG, n = 16) groups. During the whole experimental time, there were no differences between the groups with regard to average daily gain and faecal score. In TG, faecal calprotectin and zonulin values were statistically significantly decreased compared to CG, especially at week 8 (zonulin: 42.8 ± 1.54 ng/mL and 55.3 ± 42.8 ng/mL, and calprotectin: 2.91 ± 0.38 µg/g and 5.71 ± 0.43 µg/g, in TG and CG, respectively; p < 0.0001 for both comparisons). Bacteria belonging to phylum Campylobacterota decreased (p = 0.04), while those referring to genera Coprococcus and Pseudomonas increased (p = 0.01 and p = 0.04, respectively). The supplementation of the tested complementary feed can promote the intestinal health of puppies and therefore facilitate weaning by lowering gut inflammation.

Microbiome Interconnectedness throughout Environments with Major Consequences for Healthy People and a Healthy Planet.

Microbiomes have highly important roles for ecosystem functioning and carry out key functions that support planetary health, including nutrient cycling, climate regulation, and water filtration. Microbiomes are also intimately associated with complex multicellular organisms such as humans, other animals, plants, and insects and perform crucial roles for the health of their hosts. Although we are starting to understand that microbiomes in different systems are interconnected, there is still a poor understanding of microbiome transfer and connectivity. In this review we show how microbiomes are connected within and transferred between different habitats and discuss the functional consequences of these connections. Microbiome transfer occurs between and within abiotic (e.g., air, soil, and water) and biotic environments, and can either be mediated through different vectors (e.g., insects or food) or direct interactions. Such transfer processes may also include the transmission of pathogens or antibiotic resistance genes. However, here, we highlight the fact that microbiome transmission can have positive effects on planetary and human health, where transmitted microorganisms potentially providing novel functions may be important for the adaptation of ecosystems.

Exploring yeast diversity of dry-salted naturally black olives from Greek retail outlets with culture dependent and independent molecular methods.

In the present study, the physicochemical (pH, water activity, moisture content, salt concentration) classical plate counts (total viable counts, yeasts, lactic acid bacteria, Staphylococcus aureus, Pseudomonas spp., Enterobacteriaceae) and amplicon sequencing of naturally black dry-salted olives obtained from different retail outlets of the Greek market were investigated. According to the results, the values of the physicochemical characteristics presented great variability among the samples. Specifically, pH and water activity (aw) values ranged between 4.0 and 5.0, as well as between 0.58 and 0.91, respectively. Moisture content varied between 17.3 and 56.7 % (g Η2Ο/100 g of olive pulp), whereas salt concentration ranged from 5.26 to 9.15 % (g NaCl/100 g of olive pulp). No lactic acid bacteria, S. aureus, Pseudomonas spp. and Enterobacteriaceae were detected. The mycobiota consisted of yeasts that were further characterized and identified by culture-dependent (rep-PCR, ITS-PCR, and RFLP) and amplicon target sequencing (ATS). Pichia membranifaciens, Candida sorbosivorans, Citeromyces nyonsensis, Candida etchelsii, Wickerhamomyces subpelliculosus, Candida apicola, Wickerhamomyces anomalus, Torulaspora delbrueckii and Candida versatilis were the dominant species according to ITS sequencing (culture-dependent), while ATS revealed the dominance of C. etchelsii, Pichia triangularis, P. membranifaciens, and C. versatilis among samples. The results of this study demonstrated considerable variability in quality attributes among the different commercial samples of dry-salted olives, reflecting a lack of standardization in the processing of this commercial style. However, the majority of the samples were characterized by satisfactory microbiological and hygienic quality and complied with the requirements of the trade standard for table olives of the International Olive Council (IOC) for this processing style in terms of salt concentration. In addition, the diversity of yeast species was elucidated for the first time in commercially available products, increasing our knowledge on the microbial ecology of this traditional food. Further investigation into the technological and multifunctional traits of the dominant yeast species may result in better control during dry-salting and enhance the quality and shelf-life of the final product.

Selection of food cultures with protective properties for cooked ham.

Sliced cooked ham stored in modified atmosphere packaging (MAP) can be spoiled by lactic acid bacteria (LAB) which are dominating under psychrotrophic conditions. Depending on the strains, the colonization can result in a premature spoilage characterized by off-flavors, gas and slime production, discoloration, and acidification. The purpose of this study was the isolation, identification and characterization of potential food culture with protective properties, able to prevent or delay spoilage in cooked-ham. The first step was to identify by means of microbiological analysis, the microbial consortia both in unspoiled and in spoiled lots of sliced cooked ham by the use of media for the detection lactic acid bacteria and total viable count. Counts ranged from values lower than 1 Log CFU/g to 9 Log CFU/g in spoiled and unflawed samples. The interaction between consortia was then studied in order to screen for strains able to inhibit spoilage consortia. Strains showing antimicrobial activity were identified and characterized by molecular methods and tested for their physiological features. Among a total of 140 strains isolated, nine were selected for their ability to inhibit a large number of spoilage consortia, to grow and ferment at 4 °C and to produce bacteriocins. The effectiveness of the fermentation made by food culture was evaluated, through challenge tests in situ, analysing the microbial profiles of artificially inoculated cooked-ham slices during storage by high throughput 16 S rRNA gene sequencing. The native population in situ resulted competitive against the inoculated strains and only one strain was able to significantly reduce the native populations reaching about 46.7% of the relative abundance. The results obtained in this study provide information about the selection of autochthonous LAB on the base of their action against spoilage consortia, in order to select protective potential cultures able to improve the microbial quality of sliced cooked ham.

Effects of a prothioconazole- and tebuconazole-based fungicide on the yield, silage characteristics, and fungal mycobiota of corn harvested and conserved as whole-crop and high-moisture ear silages.

AIMS: To analyze the effect of a prothioconazole- and tebuconazole-based fungicide on the yield and silage characteristics of whole-crop corn (WCC) and high-moisture ear corn (HMC) silages and on the fungal community dynamics from the harvest to aerobic exposure. METHODS AND RESULTS: Corn were untreated (NT) or treated (T) with a prothioconazole- and tebuconazole-based fungicide and harvested as WCC and HMC. Silages were conserved for 60 and 160 d and subjected to an aerobic stability test. The fungicide increased the yield per hectare however, it did not affect the main nutritional characteristics of WCC or HMC. The main chemical, fermentative and microbial characteristics, dry matter (DM) losses and aerobic stability were mainly affected by the conservation time, regardless of the treatment. Fusarium, Alternaria, Aspergillus, and Penicillium genera were identified as dominant before ensiling, but Aspergillus and Penicillium became dominant after silo opening and aerobic exposure. Yeast population during ensiling and aerobic deterioration resulted in a simplification, with Pichia and Kazachstania genera being dominant. CONCLUSIONS: The application of fungicide improved the DM, starch, and net energy for lactation (NEL) yield per hectare but had no consistent effect on the microbial and fermentative silage quality and aerobic stability.

Microbial Dynamics of a Specialty Italian Raw Ewe's Milk Cheese Curdled with Extracts from Spontaneous and Cultivated Onopordum tauricum Willd.

Milk coagulants prepared by maceration of flowers harvested from both spontaneous and cultivated Onopordum tauricum Willd. and a commercially available coagulant obtained from Cynara cardunculus L. (control) were assayed for small-scale manufacturing of Caciofiore, an Italian specialty raw ewe's milk cheese produced in a family run dairy farm located in the Marche region (Central Italy). The microbiota of the three thistle-based milk coagulants and their effect on the microbial dynamics of raw milk cheeses during fermentation and maturation (from day 0 up until day 60) were investigated through a combined approach based on viable counting and Illumina DNA sequencing. In both the control and experimental cheeses, despite the slight differences emerged depending on the coagulant used, Lactococcus lactis and Debaryomyces hansenii were the prevalent species among bacteria and fungi, respectively. Moreover, raw ewe's milk was the main factor affecting the evolution of both the bacterial and fungal microbiota in all cheeses. The overall similarities between control and experimental cheeses herein analyzed supports the exploitation of Onopordum tauricum Willd. as an alternative milk coagulating agent for production of Caciofiore and, more in general, raw ewe's milk cheeses.