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Background The discovery of new molecules with antimicrobial properties has been a promising approach, mainly when related to substances produced by bacteria. The use of substances produced by bees has evidenced the antimicrobial action in different types of organisms. Thus, the use of bacteria isolated from larval food of stingless bees opens the way for the identification of the new molecules. The effect of supernatants produced by these bacteria was evaluated for their ability to inhibit the growth of bacteria of clinical interest. Furthermore, their effects were evaluated when used in synergy with antibiotics available in the pharmaceutical industry. Results A few supernatants showed an inhibitory effect against susceptible and multiresistant strains in the PIC assay and the modulation assay. Emphasizing the inhibitory effect on multidrug-resistant strains, 7 showed an effect on multidrug-resistant Escherichia coli (APEC), Klebsiella pneumoniae carbapenemase (KPC), multidrug-resistant Pseudomonas aeruginosa , and multidrug-resistant Staphylococcus aureus (MRSA) in the PIC assay. Of the supernatants analyzed, some presented synergism for more than one species of multidrug-resistant bacteria. Nine had a synergistic effect with ampicillin on E. coli (APEC) or S. aureus (MRSA), 5 with penicillin G on E. coli (APEC) or KPC, and 3 with vancomycin on KPC. Conclusion In summary, the results indicate that supernatants produced from microorganisms can synthesize different classes of molecules with potent antibiotic activity against multiresistant bacteria. Thus, suggesting the use of these microorganisms for use clinical tests to isolate the molecules produced and their potential for use.

Background Amyotrophic Lateral Sclerosis (ALS) is a rapid progressive neurodegenerative disease, characterized by a selective loss of motor neurons, brain stem and spinal cord which leads to deterioration of motor abilities. Devices that promote interaction with tasks on computers can enhance performance and lead to greater independence and utilization of technology. Objective To evaluate performance on a computer task in individuals with ALS using three different commonly used non-immersive devices. Method Thirty individuals with ALS (18 men and 12 women, mean age 59 years, range 44–74 years) with a mean score of 26, (minimum score of 14 and maximum 41) on the Revised Amyotrophic Lateral Sclerosis Functional Rating Scale (ALSFRS-R) and 30 healthy controls matched for age and gender, participated. All participants were randomly divided into three groups, each using a different device system (motion tracking, finger motion control or touchscreen) to perform three task phases (acquisition, retention and transfer). Results Both the ALS and control group (CG) showed better performance on the computer task when using the touchscreen device, but there was limited transfer of performance onto the task performed on the Finger Motion control or motion tracking. However, we found that using the motion tracking device led to transfer of performance to the touchscreen. Conclusion This study presents novel and important findings when selecting interaction devices for individuals with ALS to access technology by demonstrating immediate performance benefits of using a touchscreen device, such as improvement of motor skills. There were possible transferable skills obtained when using virtual systems which may allow flexibility and enable individuals to maintain performance overtime. Trial registration Registration name: Virtual Task in Amyotrophic Lateral Sclerosis; Registration number: NCT03113630 ; retrospectively registered on 04/13/2017. Date of enrolment of the first participant to the trial: 02/02/2016.

Nanotechnology offers promising new avenues for combating drug-resistant pathogens. Given its antioxidant capacity, the water-soluble fraction of Brazilian kefir was hypothesized to serve as an effective reducing agent for the green synthesis of silver nanoparticles (AgNPs). It was further hypothesized that both the entire fraction (WSF) and the < 10 kDa fraction AgNPs would augment the therapeutic effects of kefir, particularly its antimicrobial activity. The successful synthesis was confirmed through the use of UV-Visible spectroscopy and Fourier-transform infrared analyses. WSF-AgNPs demonstrated potent antimicrobial activity, with minimum inhibitory concentrations of 25 µg/mL against A. baumannii ( p  < 0.0001) and 50 µg/mL against K. pneumoniae ( p  < 0.0001). Although no toxicity was observed in long-term tests on adult Drosophila melanogaster , AgNPs intake impaired larvae development. Oxidative stress analysis showed mild oxidative imbalance on advanced oxidation protein products (AOPP), sulfhydryl, and reduced glutathione (GSH) contents, with no alterations observed in reactive oxygen species (ROS) quantities, ferric reducing antioxidant power (FRAP), and catalase (CAT) activity. These findings suggest that kefir-derived AgNPs may have potential for combating drug-resistant infections. Future studies should focus on enhancing specificity through compound conjugation and investigating broader applications, including disinfectants, wound healing, and antibiotic development.

Stingless bees are a diverse group with a relevant role in pollinating native species. Its diet is rich in carbohydrates and proteins, by collecting pollen and nectar supplies the development of its offspring. Fermentation of these products is associated with microorganisms in the colony. However, the composition of microorganisms that comprise this microbiome and its fundamental role in colony development is still unclear. To characterize the colonizing microorganisms of larval food in the brood cells of stingless bees Frieseomelitta varia , Melipona quadrifasciata , Melipona scutellaris , and Tetragonisca angustula , we have utilized molecular and culture-based techniques. Bacteria of the phyla Firmicutes, Proteobacteria, Actinobacteria, and fungi of the phyla Ascomycota, Basidiomycota, Mucoromycota, and Mortierellomycota were found. Diversity analysis showed that F. varia had a greater diversity of bacteria in its microbiota, and T. angustula had a greater diversity of fungi. The isolation technique allowed the identification of 189 bacteria and 75 fungi. In summary, this research showed bacteria and fungi associated with the species F. varia , M. quadrifasciata , M. scutellaris , and T. angustula , which may play an essential role in the survival of these organisms. Besides that, a biobank with bacteria and fungus isolates from LF of Brazilian stingless bees was created, which can be used for different studies and the prospection of biotechnology compounds.

Characterizing the complex web of ecological interactions is a central challenge in molecular ecology. Shotgun metagenomics of environmental samples offers a powerful, high‐resolution approach, yet its potential for simultaneously generating multiple genomic resources from different trophic levels remains underexplored. This study serves as a proof‐of‐concept, using deep sequencing of a single, complex sample—the larval food of the stingless bee Tetragonisca angustula—to demonstrate the method's capacity to recover genomic information across varying template abundances. We successfully assembled three genomes of different completeness levels: a near‐complete bacterial genome (Acetilactobacillus jinshanensis, 2,097,977 bp with 0.002% ambiguous bases), a draft mitochondrial genome (T. angustula, 15,498–15,549 bp), and a fragmented chloroplast genome (Lactuca sativa, 130,532 bp with 23.47% ambiguous bases). The assembly quality gradient, observed from complete to fragmented, directly reflects the relative abundance of each DNA template in the environmental sample, demonstrating the method's sensitivity and ecological informativeness. Beyond these genomic resources, the data provided a comprehensive biodiversity profile, revealing DNA from seven major taxonomic groups, including 209 bacterial genera, 123 plant families, and 55 insect taxa. Additionally, genomic comparisons using Average Nucleotide Identity (ANI) and digital DNA–DNA Hybridization (dDDH) analyses suggest that the dominant bacterial strain represents a putative novel species within the genus Acetilactobacillus. This approach simultaneously provided insights into host genetics, food sources, and microbial communities, illustrating the potential of single metagenomic datasets to generate multiple valuable genomic resources for molecular ecology research. This study serves as a proof‐of‐concept, demonstrating that deep shotgun sequencing of a single complex sample—stingless bee larval food—can simultaneously generate multiple genomic resources. From this dataset, we assembled three genomes (a near‐complete bacterium, a draft host mitochondrion, and a fragmented plant chloroplast) with varying completeness. This assembly quality gradient directly reflects the relative abundance of each DNA template, showcasing the method's sensitivity and its utility for providing ecological insights from genomic data.

Alzheimer’s disease (AD) is a progressive neurodegenerative condition and the primary form of dementia among elderly people. The amyloidogenic hypothesis is the main theory that explains this phenomenon and describes the extracellular accumulation of amyloid beta (Aβ) peptides. Model organisms such as Drosophila melanogaster have been utilized to improve the understanding of this disease and its treatment. This study evaluated the effects of peptide and metabolic fractions of Brazilian kefir on a strain of D. melanogaster that expresses human Aβ peptide 1–42 in the eye. The parameters assessed included ommatidial organization, vacuole area, retinal thickness, and Aβ peptide quantification. The present study revealed that the fractions, particularly the peptidic fraction, significantly reduced the vacuole area and increased the retina thickness in treated flies, indicating an improvement in neurodegeneration phenotype. The peptidic fraction was also found to alter Aβ aggregation dynamics, inhibiting Aβ fibril formation, as revealed by dynamic light scattering. This study demonstrated that kefir fractions, particularly the peptidic fraction < 10 kDa, have the potential to regulate Aβ aggregation and alleviate neurodegeneration in a Drosophila melanogaster AD-like model. These findings suggest that kefir fractions could be viable for the bioprospection of novel drug prototypes for AD treatment, providing valuable insights into strategies targeting Aβ aggregation and neurodegeneration in AD.

This study explores the green synthesis of silver nanoparticles (AgNPs) using a methanolic extract of fermented pollen from Tetragonisca angustula, a species of stingless bees. The AgNPs exhibit spherical morphology, low charge values, and suspension stability, with their unique composition attributed to elements from the pollen extract. Antioxidant assays show comparable activity between the pollen extract and AgNPs, emphasizing the retention of antioxidant effects. The synthesized AgNPs demonstrate antimicrobial activity against multidrug-resistant bacteria, highlighting their potential in combating bacterial resistance. The AgNPs exhibit no toxic effects on Drosophila melanogaster and even enhance the hatching rate of eggs. The study underscores the innovative use of stingless bee pollen extract in green synthesis, offering insights into the varied applications of AgNPs in biomedicine.

Key messageAdult plants are more vulnerable to nematode galls, while juvenile stages are more susceptible to chewing insect herbivores and fungal pathogen.Plants are characterized for having a great temporal variation in different traits along the stages of their development, affecting indirectly the susceptibility to herbivore and pathogen damage. We evaluated the effects of plant ontogeny on the damage of chewing insect herbivores, nematode galls and parasitic fungi in the shrub Miconia albicans (Sw.) Triana (Melastomataceae) in Brazilian Cerrado. Herbivore and pathogen damage were different between ontogenic stages. Adult plants were more vulnerable to leaf damage by nematode galls, while juvenile stages were more susceptible to chewing insect herbivores and fungal pathogen. Chlorophyll content was significantly higher in adults than in juvenile stages. However, in the juvenile stages, the chlorophyll content was correlated with the damage index per plant. Our results highlight the complexity of plant–herbivore–pathogen interactions throughout plant ontogeny due to the complexity of chemical/physiological mechanisms involved that can affect this interaction.

Folic acid content was evaluated in food preparations containing wheat and corn flour submitted to baking, deep-frying, and steaming. Commercially fortified flours showed the absence of folic acid. Flours with laboratory folic acid fortification showed 487 and 474 μg of folic acid in 100 g of wheat and corn flours, respectively. In the corn flour preparations, the cake had the highest retention (99%) when compared to couscous (97%). Besides, the cake showed higher retention when compared to the wheat flour preparations due to the interactions of the folic acid with the hydrophobic amino acids of the Zein, a protein found in corn. In wheat flour preparations, vitamin retention was 87%, 80% and 57% in bread, cake, and White sauce respectively. These findings relate to the change of the physicochemical properties of food components that occurs during mixing and cooking of the ingredients.

Kefir is a probiotic-rich fermented milk beverage composed of a symbiotic consortium of bacteria and yeasts. Emerging evidence has shown its neuroprotective potential, including that of its derived metabolites and fractions, in mitigating β-amyloid (Aβ42)-induced neurotoxicity in cultured neuronal cells and neurodegeneration in Drosophila melanogaster models for Alzheimer's disease (AD). Building on these findings, we explored the in vitro effects of kefir-derived fractions and synthetic peptides on Aβ42 aggregation and disaggregation. Two kefir fractions, Ethyl Acetate (EtOAc) and <10kDa, and two kefir-derived peptides (KDPs) identified in our prior research were tested. For the preventive assay, Aβ42 (10 µM) was co-incubated with kefir fractions (0.25 mg/mL) or KDPs (1, 10 and 100 µM) for 24 hours, with fluorescence readings (Thioflavin T) taken hourly. For the treatment assay, Aβ42 was incubated alone for 48 hours to induce aggregation, followed by treatment with fractions or KDPs, with fluorescence readings taken after an additional 48-hour incubation. All experiments were performed in 96-well plates, with samples in quintuplicate. Statistical analysis was conducted using one-way ANOVA. Fluorescence intensity measurements revealed that, in the preventive assay, all treatments significantly reduced Aβ42 aggregation compared to the untreated control (p<0.0001). In the treatment assay, significant disruption of Aβ42 aggregation was observed with KDP-1 (p=0.0055) and KDP-2 (p<0.0001). This study highlights the potential ability of kefir fractions and synthetic peptides to prevent and disrupt Aβ42 aggregation in vitro, supporting their therapeutic promise in neurodegenerative disorders. Further studies should explore their mechanisms of action and efficacy in vivo.