Cultivable Microbiota Research Articles

The evolving world of the urinary microbiome.

The existence of urinary microbiome in healthy individuals is now widely accepted as the longstanding belief in urinary tract sterility was disproved over a decade ago. The urinary microbiome has since been implicated in multiple urologic conditions including urinary tract infection (UTI), urinary incontinence, and bladder cancer. This review relays new findings of urinary microbiome compositional changes associated with aging and UTI susceptibility. Recent advancements have established how the urinary microbiome changes over the lifespan. Studies finding distinct urinary microbiomes in prepubescent, reproductive age, and postmenopausal females have identified sex hormones as potential modulators of urinary microbiome composition and have identified prevalent species that may be markers of dysbiosis. Research in male children finds a cultivable urinary microbiota that varies with age or urologic history but not delivery mode. Emerging research also addresses the function of the urinary microbiota, including genetic factors associated with urinary tract colonization and interactions with uropathogens. The urinary microbiome is a promising therapeutic target for urologic disease. However, a more functional understanding is necessary for the development of microbiome-based therapies. Future research should develop accurate animal models and explore functional relationships between the urinary microbiome and the host environment.

Biodiversity and biotechnological potential of cultivable Halophilic bacteria from Slana voda (Oravska Polhora, Slovakia) natural salt spring

AbstractHalophilic microorganisms are of immense importance in various fields of biotechnology. There is a multitude of actual or potential applications in the research of environmentally friendly applications in biodegradation, decolorization, food biotechnology, and biopolymers production. Thirty-eight strains of halophilic bacteria were isolated from the Slana voda (Slovakia, Central Europe) natural salt spring, with a tolerance of up to 20% of NaCl. The Halomonas genus accounted for more than 35% of the cultivable microbiota, followed by Shewanella and Pseudoaltermonas genera. More than 55% of bacterial isolates were able to produce at least one of the tested hydrolases (cellulase, lipase, amylase, protease) and three of them were positive for all four enzyme activities. Bacterial isolates showed a relatively high ability to degrade synthetic dyes, namely congo red, crystal violet, malachite green, methylene blue, methyl red, and safranin (5.26, 42.11, 44.74, 63.16, 92.18, and 18.42% of isolates respectively). Interestingly only a small overlap was observed between the isolates producing extremozymes and the isolates demonstrating decolorizing activity.

Clinical and Microbial Determinants of Upper Respiratory Colonization with Streptococcus pneumoniae and Native Microbiota in People with HIV-1 and Control Adults.

The substantial risk for respiratory and invasive infections with Streptococcus pneumoniae (Spn) among people with HIV-1 (PWH) begins with asymptomatic colonization. The frequency of Spn colonization among U.S. adults with and without HIV-1 infection is not well-characterized in the conjugate vaccine era. We determined Spn colonization frequency by culture and specific lytA gene QPCR and microbiota profile by 16S rRNA gene sequencing in nasopharyngeal (NP) and oropharyngeal (OP) DNA from 138 PWH and 93 control adults and associated clinical characteristics. The frequencies of Spn colonization among PWH and controls did not differ (11.6% vs 8.6%, respectively; p=0.46) using combined results of culture and PCR, independent of vaccination or behavioral risks. PWH showed altered microbiota composition (i.e., beta-diversity. NP: p=0.0028, OP: p=0.0098), decreased alpha-diversity (NP: p=0.024, OP: p=0.0045), and differences in the relative abundance of multiple bacterial taxa. Spn colonization was associated with altered beta-diversity in the NP (p=0.011), but not OP (p=0.21). Despite widespread conjugate vaccine and antiretroviral use, frequencies of Spn colonization among PWH and controls are currently consistent with those reported in the pre-conjugate era. The persistently increased risk of pneumococcal disease despite ART may relate to behavioral and immunologic variables other than colonization.

Cultivable epiphytic bacteria of the Chlorophyta Ulva sp.: diversity, antibacterial, and biofilm-modulating activities.

Macroalgae harbor a rich epiphytic microbiota that plays a crucial role in algal morphogenesis and defense mechanisms. This study aims to isolate epiphytic cultivable microbiota from Ulva sp. surfaces. Various culture media were employed to evaluate a wide range of cultivable microbiota. Our objective was to assess the antibacterial and biofilm-modulating activities of supernatants from isolated bacteria. Sixty-nine bacterial isolates from Ulva sp. were identified based on 16S rRNA gene sequencing. Their antibacterial activity and biofilm modulation potential were screened against three target marine bacteria: 45%, mostly affiliated with Gammaproteobacteria and mainly grown on diluted R2A medium (R2Ad), showed strong antibacterial activity, while 18% had a significant impact on biofilm modulation. Molecular network analysis was carried out on four bioactive bacterial supernatants, revealing new molecules potentially responsible for their activities. R2Ad offered the greatest diversity and proportion of active isolates. The molecular network approach holds promise for both identifying bacterial isolates based on their molecular production and characterizing antibacterial and biofilm-modulating activities.

Development of functional consortia for the pretreatment of compostable lignocellulosic waste: A simple and effective solution to a large-scale problem

Microorganisms drive the degradation of organic matter thanks to their enzymatic versatility. However, the structure of lignocellulose poses a great challenge for the microbiota inhabiting a compost pile. Our purpose was to increase the biodegradability of vegetable waste in the early stages of the composting process by applying a microbial consortium with lignocelllulolytic capacity. For this, a previous screening was performed among the culturable microbiota from different composting processes to find inoculants with ligninocellulolytic activity. Selected strains were applied as a pure culture and as a microbial consortium. The starting material was composed of tomato plant and pruning remains mixed in a ratio (50:50 v/v), whose humidity was adjusted to around 65%. To determine the ability of both treatments to activate the biodegradation of the mixtures, moisture, organic matter, ash, C/N ratio, 4-day cumulative respirometric index (AT4) and degradation rates of cellulose, hemicellulose and lignin were evaluated. Subsequently, a real composting process was developed in which the performance of the microbial consortium was compared with the composting process without inoculum (control). According to our tests, three microbial strains (Bacillus safensis, Bacillus licheniformis and Fusarium oxysporum) were selected. The results showed that the application of the bacteria strains at low doses (104 CFU g−1 on the complete residual material of the pile) resulted in higher rates of lignocelullose degradation after 10 days of treatment compared to that observed after application of the fungus in pure culture or untreated controls. The implementation of the strategy described in this work resulted in obtaining compost with better agronomic quality than the uninoculated controls. Therefore, the application of this consortium could be considered as an interesting tool for bioactivation of lignocellulosic waste prior to the composting process.

Exploring the health benefits of traditionally fermented wax gourd: flavor substances, probiotics, and impact on gut microbiota

BackgroundThe fermented wax gourd, often referred to as “smelly wax gourd,” is a traditional food that undergoes natural fermentation. It’s a staple in eastern China and is recognized as Ningbo’s “city-fermented food.” Characterized by its distinct putrid flavor and soft texture, its safety, nutritional aspects, and sensory attributes have not been extensively studied.MethodsIn this research, the microbial community and flavor components of fermented wax gourd during its traditional fermentation were analyzed. The safety and impact on the gut microbiota were also assessed by administering it to healthy and pseudo-germ-free mice.ResultsThe findings revealed that organic acids primarily contribute to the gourd’s flavor during fermentation. The aroma reminiscent of fruits is due to 2-methyl-butyric acid, while butyric, pentanoic, caproic, and octanoic acids are responsible for their characteristic smelly taste. In the fermentation of traditional foods, the abundance of substances and open fermentation contribute to the diversity of microorganisms in the system, and the reproduction and metabolism of microorganisms drive the fermentation of foods. From the results of this study, the flavor peaks on the 10th day of fermentation. Predominant microbes include Lactobacillus fermentum, Streptococcus equinus, Fusobacterium perfoetens, Weissella confusa, and Lactobacillus plantarum. Notably, Lactobacillus was the most abundant probiotic in the early fermentation stages. The “smelly” taste of smelly wax gourd was mainly derived from butyric acid, valeric acid, caproic acid, caprylic acid, p-methylphenol and other compounds, and the abundance of Caldicoprobacter algeriensis, Mariniphaga anaerophila, Streptococcus equi and Lactobacillus were significantly correlated with 4 of the above 5 acids. These four bacteria may contribute more to the “smelly” taste of smelly wax gourd. In the study, compared with the control group (CONT), the abundance of Helicobacter ganmani, H. Chanicola, Lactobacillus animalis, Lactobacillus gadi and Lactobacillus reuteri decreased in mice groups treated with anti-biological pretreatment followed by gavage of smelly wax gourd (A.SWG) and the smelly wax gourd (SWG) groups. Conversely, Muribaculum intestinale, Prevotellamassilia timonensis, Alistipes putredinis, Kineothrix alysoides and Clostridium indolis’ abundance of increases. Mice that underwent fecal microbiota transplantation (FMT) exhibited a higher abundance of probiotics like Bifidobacterium animalis, Bifidobacterium pseudolongum, Lactobacillus johnsonii, and others compared to the fecal culture microbiota transplantation (CMT) group. However, the CMT group had a higher presence of fermented and Royce lactobacilli.ImplicationConsuming fermented wax gourd can enhance the presence of beneficial probiotics and reduce pathogenic Helicobacter sp. in the mouse gut. Both Lactobacillus sp. and Bifidobacterium sp. showed increased abundance post fecal microbiota and fecal culture microbiota transplantation.

The Common and Unique Microbiota in Sabah’s Traditional Rice Wine Starter Cultures (SASAD)

Rice wine is an alcoholic beverage produced through the fermentation of cereal grains, mainly rice, with microbial starters consisting of fungi and bacteria. However, the microbes in the rice wine starter cultures have never been documented comprehensively except for a few studies that looked into culturable microbes. Hence, their exact core microbiota contents especially those unculturable microbes remained unknown. Therefore, this research aimed to identify the fungal and bacterial communities in sasad through ribosomal amplicon-based next-generation sequencing and analysis that captured both the culturable and unculturable microbiota. The results showed that two fungal phyla (Mucoromycota and Ascomycota) with five genera (Mucor, Rhizopus, Saccharomycopsis, Wickerhamomyces, and Kodamaea) and two bacterial phyla (Proteobacteria and Firmicutes) with 10 genera (Kosakonia, Weissella, Enterobacter, Lactococcus, Pseudomonas, Bacillus, Chromobacterium, Paludibacterium, Enterococcus, and Gluconobacter) were identified as the core microbiota (relative abundance > 1.00%) in the sasad samples. Some of these microbes have been reported in other starter cultures, but some are unique to the sasad (Chromobacterium and Paludibacterium). Hence, this research provides the first comprehensive report on the microbes in sasad and provides important insights into the potential roles of core microbiota. These data may be used to facilitate the development of starter cultures with defined microbial compositions for the consistent production of safe and high-quality rice wines in the future.

Analysis of the culturable gut yeast microbiota of dogs with digestive disorders

Despite the increasing interest in studying the gut mycobiota of dogs, the association between fungal colonization and the development of digestive disorders in this species remains largely understudied. On the other hand, the high prevalence of antifungal-resistant yeasts detected in previous studies in samples from animals represents a major threat to public health. We analyzed the presence of culturable yeasts in 112 rectal swab samples obtained from dogs with digestive disorders attended in a veterinary teaching hospital. Our results revealed that Malassezia pachydermatis was frequently isolated from the studied dog population (33.9% of samples), and that the isolation of this yeast was significantly associated to the age of animals, but not to their sex, disease group, or the presence of vomits and/or diarrhea. In contrast, other yeast species were less prevalent (17.9% of samples in total), and their isolation was not significantly associated to any variable included in the analysis. Additionally, we observed that 97.5% of the studied M. pachydermatis isolates (n = 158, 1–6 per positive episode) displayed a minimum inhibitory concentration (MIC) value >4 μg/ml to nystatin, 31.6% had a MIC ≥32 μg/ml to fluconazole, and 27.2% had a MIC >4 μg/ml to amphotericin B. The antifungal susceptibility profiles of non-Malassezia (n = 43, 1–7 per episode) were more variable and included elevated MIC values for some antifungal-species combinations. These results confirm that the intestine of dogs is a reservoir of opportunistic pathogenic yeasts and suggest that the prevalence of M. pachydermatis colonization depends more on the age of animals than on any specific digestive disorder.

Two human milk-like synthetic bacterial communities displayed contrasted impacts on barrier and immune responses in an intestinal quadricellular model.

The human milk (HM) microbiota, a highly diverse microbial ecosystem, is thought to contribute to the health benefits associated with breast-feeding, notably through its impact on infant gut microbiota. Our objective was to further explore the role of HM bacteria on gut homeostasis through a "disassembly/reassembly" strategy. HM strains covering the diversity of HM cultivable microbiota were first characterized individually and then assembled in synthetic bacterial communities (SynComs) using two human cellular models, peripheral blood mononuclear cells and a quadricellular model mimicking intestinal epithelium. Selected HM bacteria displayed a large range of immunomodulatory properties and had variable effects on epithelial barrier, allowing their classification in functional groups. This multispecies characterization of HM bacteria showed no clear association between taxonomy and HM bacteria impacts on epithelial immune and barrier functions, revealing the entirety and complexity of HM bacteria potential. More importantly, the assembly of HM strains into two SynComs of similar taxonomic composition but with strains exhibiting distinct individual properties, resulted in contrasting impacts on the epithelium. These impacts of SynComs partially diverged from the predicted ones based on individual bacteria. Overall, our results indicate that the functional properties of the HM bacterial community rather than the taxonomic composition itself could play a crucial role in intestinal homeostasis of infants.

Evaluation of cultivable aerobic vaginal microbiota of repeat breeder and healthy pregnant dairy cows

Evaluation of cultivable aerobic vaginal microbiota of repeat breeder and healthy pregnant dairy cows

Pioneer access of the foam nest bacterial community of Leptodactylidae frogs and its biotechnological potential.

Many anuran amphibians deposit their eggs in foam nests, biostructures that help protect the eggs and tadpoles from predators. Currently, there are no other identification and description studies of the cultivable microbiota role in the nests of the Leptodactylid frogs such as Physalaemus cuvieri, Leptodactylus vastus and Adenomera hylaedactyla. This study aimed to isolate and identify the culturable bacteria from these three anuran species' nests, as well as to prospect enzymes produced by this microbiota. Foam nests samples and environmental samples were diluted and viable cell count was determined. Bacterial morphotypes from foam nest samples were isolated through spread plate technique. Isolates' DNAs were extracted followed by rRNA 16S gene amplification and Sanger sequencing. To evaluate their enzymatic potential, the isolates were cultured in ATGE medium supplemented with starch (0.1% w/v), gelatin (3% w/v) and skimmed milk (1% w/v), to verify amylase and protease activity. A total of 183 bacterial morphotypes were isolated, comprising 33 bacterial genera. Proteobacteria phylum was the most abundant in all the three nests (79%). The genera Pseudomonas and Aeromonas were the most abundant taxon in P. cuvieri and L. vastus. In A. Hylaedactyla, were Enterobacter and Bacillus. Regarding enzymatic activities, 130 isolates displayed protease activity and 45 isolates were positive for amylase activity. Our results provide unprecedented information concerning culturable bacterial microbiota of the foam nests of the Leptodactylid frogs, as well as their potential for biomolecules of biotechnological interest.

First report of Kurthia gibsonii in the digestive system of Apis mellifera in an indigenous community in the south of Mexico

The insect digestive system is an outstanding niche for recognizing and understanding features and interactions with unique microbiota. Apis melliferaplay an important role in honey production and pollination, but their populations have decreased over time, so their study and comprehension are vital. Specimens were collected to study the culturable microbiota of the digestive system in an indigenous community in southern Mexico. Digestive samples of bees from four apiaries were randomly analyzed and cultured, and Gram-positive bacilli were identified through conventional biochemical tests and with molecular markers. Kurthia gibsoniiwas identified in 7.5% (6/80) of the cases, and the sequences obtained were reported in GenBank. This is the first report of K. gibsoniiin the digestive system of bees in apiaries in southern Mexico.

Microbiota Diversity in Non-Small Cell Lung Cancer Gut and Mouth Cavity Microbiota Diversity in Non-Small Cell Lung Cancer Patients.

Lung malignancies have a substantial impact on cancer incidence and mortality worldwide. Even though many factors involved in the development of the disease are known, many questions remain unanswered. Previous studies suggest that the intestinal microbiota may have a role in developing malignant diseases. According to some findings, the microbiota has proven to be a key modulator of carcinogenic processes and the immune response against cancer cells, potentially influencing the effectiveness of immunotherapy. In our study, we characterized culturable microorganisms associated with non-small cell lung cancer (NSCLC) that can be recovered from rectal swabs and mouthwash. In addition, we also explored differences in the culturable microbiota with two main types of NSCLC - adenocarcinoma (ADC) and squamous cell carcinoma (SCC). With 141 patients included in the study (86 ADC and 55 SCC cases), a significant difference was observed between the two types in seven bacterial species (Collinsella, Corynebacterium, Klebsiella, Lactobacillus, Neisseria, Rothia, and Streptococcus), including the site of origin. The relationship between microbial dysbiosis and lung cancer is poorly understood; future research could shed light on the links between gut microbiota and lung cancer development.

Cultivable Gut Microbiota in Synanthropic Bats: Shifts of Its Composition and Diversity Associated with Hibernation

The role of bats in the global microbial ecology no doubt is significant due to their unique immune responses, ability to fly, and long lifespan, all contributing to pathogen spread. Some of these animals hibernate during winter, which results in the altering of their physiology. However, gut microbiota shifts during hibernation is little studied. In this research, we studied cultivable gut microbiota composition and diversity of Nyctalus noctula before, during, and after hibernation in a bat rehabilitation center. Gut microorganisms were isolated on a broad spectrum of culture media, counted, and identified with mass spectrometry. Linear modeling was used to investigate associations between microorganism abundance and N. noctula physiological status, and alpha- and beta-diversity indexes were used to explore diversity changes. As a result, most notable changes were observed in Serratia liquefaciens, Hafnia alvei, Staphylococcus sciuri, and Staphylococcus xylosus, which were significantly more highly abundant in hibernating bats, while Citrobacter freundii, Klebsiella oxytoca, Providencia rettgeri, Citrobacter braakii, and Pedicoccus pentosaceus were more abundant in active bats before hibernation. The alpha-diversity was the lowest in hibernating bats, while the beta-diversity differed significantly among all studied periods. Overall, this study shows that hibernation contributes to changes in bat cultivable gut microbiota composition and diversity.

Bacterial microbiota associated with the leaf‐cutting ant Atta cephalotes (Hymenoptera: Myrmicinae): Dynamics during development and potential role in defence

AbstractThe biological complexity of leaf‐cutting ants is determined in part by both positive and negative associations with microorganisms. These ants constantly face microorganisms that can compromise workers’ survival and the integrity of their symbiont fungus. The ability to produce antimicrobial compounds within the colony, both by the workers and by associated microorganisms, is an adaptive response that protects against these natural enemies. Atta cephalotes (Linnaeus, 1758) is an ecologically successful species with a great capacity to overcome pathogenic microorganisms. In contrast to the Acromyrmex genus, the evidence suggests that it does not maintain an association with antibiotic‐producing actinobacteria raising the question of whether this species maintains associations with bacterial communities that can potentially protect the colony against prejudicial microorganisms. In this direction, the diversity and composition of the culturable bacterial microbiota associated with A. cephalotes developmental stages were evaluated, as well as their potential to inhibit the growth of the entomopathogenic fungus Metarhizium anisopliae and the mycoparasite Trichoderma sp. Six nests were collected, of which a total of 900 larvae, 900 pupae and 900 adult workers were analysed. Culture‐dependent and molecular methods were used to identify the strains to genus level. To determine differences in bacterial composition in the development stages, analysis of the contribution to dissimilarity (SIMPER) were performed. Seventy‐seven strains corresponding to 18 genera were documented. Acinetobacter was the dominant one. On the other hand, Acinetobacter, Bacillus, Enterobacter, Serratia and Microbacterium were maintained from the larval to the adult stage. Furthermore, except for Acinetobacter, different strains of these bacterial groups significantly inhibited pathogenic fungi growth. The results suggest the existence of a persistent association of A. cephalotes with strains of these bacterial genera and a potential role in defence at the collective level.

Research Note: Preliminary results, first detection of Enterococcus cecorum from environmental samples by streaking on X-Gluc containing selective media

The isolation of cultivable E. cecorum from the environment of poultry houses remains a challenge. Environmental samples (dust wipes, equipment swabs, pooled feces) and samples from culled bird vertebras were collected from an infected broiler flock on d 37 posthatching. To isolate the bacterium from the cultivable microbiota, suspensions from the environmental samples were streaked onto a blood agar base medium supplemented with 5-bromo-4-chloro-3-indolyl-beta-D-glucuronic acid cyclohexylammonium salt (X-Gluc), colistin sulfate, and nalidixin. The chromogenic reaction facilitated the isolation of E. cecorum from contaminated surfaces and pooled feces. Isolates from both the environment and vertebras were confirmed using MALDI-TOF and PCR analysis. Colony appearance and antimicrobial susceptibility tests revealed no phenotypic differences among the isolates. It remained unclear whether the isolates originated from the same clone. However, the principle of isolating the pathogen by streaking on a chromogenic agar may motivate researchers to investigate the transmission routes of infectious isolates, potentially leading to the optimization of biosecurity measures.

Isolation and Characterization of Culturable Osmotolerant Microbiota in Hypersaline and Hypergypsic Soils as New Treatment for Osmotic Stress in Plants

Saline and gypsic soils impede or condition the establishment of farms in many regions worldwide. Stress caused by the accumulation of sodium or calcium ions in the soil drastically limits plant growth and is a limiting factor in the production of many crops. For this reason, saline and gypsic soils were preferentially exploited for mineral extraction. However, nowadays, they can be a source of new biotechnological tools to help in the osmotic stress to which some crops are exposed. In these environments, despite being traditionally characterized by their low biodiversity, we can find well-adapted microbiota that may be able to interact with plants to deal with different environmental stresses. These mechanisms may consist of a very important contribution to the development of new osmotic stress-dealing bioinoculants. The present study sought to elucidate the diversity of the cultivable population of such environments and use them as regulators of soil nutrients and stress-relieving symbionts in plants under osmotic stress. Among the candidate strains selected to cover more scenarios, we found that the strains Stutzerimonas stutzeri A38 and Bacillus pumilus A49 were able to increase root size under osmotic stress in Medicago sativa and Medicago polymorpha plants. Moreover, Peribacillus frigoritolerans A70 and Bacillus licheniformis A46 also enhanced the performance in M. polymorpha, showing interesting potential for a future use in wasteland use for production to livestock feeding or other relevant industries.

Characterization of the Cultivable Microbiota Components of Marine Bioaerosols in the North Tropical Atlantic

Microorganisms are key to balancing marine ecosystems and have complex interactions at the ocean–atmosphere interface, affecting global climate and human health. This research investigated the diversity of cultivable bacteria and fungi in marine bioaerosols in the North Tropical Atlantic Ocean. Using the technique of spontaneous sedimentation in selective culture media, samples were collected during oceanographic expeditions. After isolation and purification, microbial strains were identified by phenotypic and genetic analyses. Fungi isolated included Acrophialophora, Aspergillus, Chrysosporium, Cladosporium, Fonsecaea, Mucor, Rhodotorula, Schizophyllum, Stemphylium, Candida, Curvularia, Cystobasidium, Exophiala, Neotestudina, Penicillium, Pestalotiopsis, and Preussia. The bacterial isolates belonged to the Bacillota, Pseudomonadota, Enterobacteriaceae family, Bacillus genus, and Serratia liquefaciens groups. About 40% of bacteria and 42% of fungi were identified as potential human pathogens, suggesting a relationship between human actions and the microbiota present in bioaerosols on the high seas. Sea surface temperature (SST) and wind speed influenced microorganisms. More studies and analyses in different scenarios should be conducted considering environmental and climate variables in order to deepen knowledge and generate information on the subject, so that standards can be established, and quality parameters determined.

CHARACTERIZATION OF THE CULTURABLE GUT MICROBIOTA OF TWO COLOMBIAN MAIN MALARIA VECTORS

Bacteria inhabiting the gut of malaria vectors can strongly influence their biology and competence to transmit Plasmodium parasites and other pathogens. This study aimed to isolate and characterize the culturable gut bacterial microbiota in two main Colombian malaria vectors. Anopheles (Diptera: Culicidae) darlingi Root, 1926 and Anopheles (Diptera: Culicidae) nuneztovari Gabaldón, 1940, specimens were collected in two malaria-endemic regions and under two feedings status. The bacterial composition was compared according to mosquito species, geography, and feeding status. Bacterial isolates from homogenized mosquito guts were morphologically and biochemically characterized, and their taxonomy was determined by 16S rRNA sequencing. Results showed that Gram-negative bacilli, particularly of the Proteobacteria phylum, are predominant in the gut of the two-vector species regardless of geography and feeding status. At the genus level, Enterobacter, Acinetobacter, and Bacillus were common among the two-vector species and geographic sites; and some genera were locality or vector-specific. In addition, the presence of blood in the mosquito gut negatively impacted bacterial richness at the genus level. These results advanced the knowledge of mosquito-microbe interactions for these malaria vectors. In addition, the generation of a bacterial culture repertoire may allow us to investigate the potential role of some bacteria as biocontrol agents.

Safety and Effects of Intravaginal Administration of Lacticaseibacillus rhamnosus CRL1332 Immobilized on Nanofibers in a Murine Experimental Model

The design of probiotic hygiene products for daily use is considered an adequate alternative for the restoration of the vaginal microbiome, maintaining health, and/or preventing infections of the female urogenital tract. Most of these probiotic products are available on the world market, but their efficacy and safety are not sufficiently documented. One of the requirements to transfer novel probiotic formulas/products to the productive sector is to demonstrate their innocuity and the absence of adverse or collateral effects on the host, mainly assayed in experimental models. The inclusion of beneficial lactobacilli in nanofibers by electrospinning technique has shown promising application possibilities, and the immobilization of Lacticaseibacillus rhamnosus CRL1332 in nanofibers with and without bioprotective substances and their characterization were previously performed by our research group. In this work, the safety of the intravaginal (i.va.) administration of these functional nanofibers in a murine experimental model was evaluated. L. rhamnosus CRL1332 immobilized in different nanofibers was intravaginally inoculated into mice (seven daily doses). Vaginal washes were taken for microbiological (cultivable lactobacilli) and cytological techniques, and the vagina was used for histological and morphological-ultrastructural evaluation. Our results demonstrated that the intravaginal administration of L. rhamnosus CRL1332 immobilized in nanofibers is safe in murine models, given the absence of an inflammatory response at the cytological and histological levels, with minor modifications at the ultrastructural level, and also related to the normal cultivable vaginal microbiota. On the other hand, the number of cultivable lactobacilli increased in the vagina of mice receiving L. rhamnosus CRL1332 nanofibers. The results indicate the safety of lactobacilli-functional nanofibers and support their inclusion in the design of vaginal probiotic products to prevent/treat urogenital infections and reconstitute the women’s vaginal microbiota.