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The use of recreational waters is a widespread activity worldwide, and one of the risks associated with this practice is the exposure of bathers to microorganisms that may arise due to pollution caused by inadequate infrastructure and sanitation. In the present work, we isolated Candida spp. (n = 24) from five recreational beaches in Rio de Janeiro, Brazil, in order to evaluate their susceptibility to antifungals, the production of virulence attributes and the in vivo virulence using Tenebrio molitor larvae as a model. The ITS1-5.8S-ITS2 gene sequencing identified thirteen isolates (54.1 %) as C. tropicalis, seven (29.1 %) as C. krusei (Pichia kudriavzevii), one (4.2 %) as C. rugosa (Diutina rugosa), one (4.2 %) as C. mesorugosa (Diutina mesorugosa), one (4.2 %) as C. utilis (Cyberlindnera jadinii) and one (4.2 %) as C. parapsilosis. C. tropicalis isolates showed resistance to azoles and susceptibility to amphotericin B, flucytosine and caspofungin. C. krusei isolates were resistant to fluconazole, caspofungin and itraconazole, with 42.8 % resistance to flucytosine, besides susceptibility to voriconazole and amphotericin B. The remaining species were susceptible to all tested antifungals. All Candida isolates adhered to abiotic surfaces and formed biofilm on polystyrene, albeit to varying degrees, and produced aspartic protease and hemolytic activity, which are considered fungal virulence attributes. C. tropicalis, C. krusei and C. utilis isolates produced phytase, while the only esterase producer was C. tropicalis. Regarding resistance to osmotic stress, all isolates of C. tropicalis, C. parapsilosis and C. mesorugosa grew up to 7.5 % NaCl; the remaining isolates grew up to 1.87-3.75 % NaCl. The mortality caused by fungal challenges in T. molitor larvae was variable, with C. tropicalis, C. utilis and C. parapsilosis being more virulent than C. krusei and C. rugosa complex. Collectively, the presence of these yeasts, particularly the virulent and resistant isolates, in recreational waters can pose a significant health risk to bathers.

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Medicinal plants, such as Talisia esculenta, are rich in antioxidant biomolecules, which are used in the treatment and prevention of many diseases. The antioxidant potential of T. esculenta extracts obtained from leaves and fruit peels was investigated using biochemical and 3T3 cell line assays as well as in vivo assays using an organism model Tenebrio molitor. Four extracts were tested: hydroethanolic extracts from leaves (HF) and from fruit peels (HC), and infusion extracts from leaves (IF) and from fruit peels (IC). The biochemical assays demonstrated an antioxidant capacity verified by TAC, reducing power, DPPH, and copper chelating assays. None of the extracts exhibited cytotoxicity against 3T3 cells, instead offering a protection against CuSO4-induced oxidative stress. The antioxidant activity observed in the extracts, including their role as free radical scavengers, copper chelators, and stress protectors, was further confirmed by T. molitor assays. The CLAE-DAD analysis detected phenolic compounds, including gallic acid, rutin, and quercitrin, as the main constituents of the samples. This study highlights that leaf and fruit peels extracts of T. esculenta could be effective protectors against ROS and copper-induced stress in cellular and invertebrate models, and they should be considered as coadjutants in the treatment and prevention of diseases related to oxidative stress and for the development of natural nutraceutical products.

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Invertebrates can provide a valuable alternative to traditional vertebrate animal models for studying bacterial and fungal infections. This study aimed to establish the larvae of the coleoptera Tenebrio molitor (mealworm) as an in vivo model for evaluating virulence and horizontal gene transfer between Staphylococcus spp. After identifying the best conditions for rearing T. molitor, larvae were infected with different Staphylococcus species, resulting in dose-dependent killing curves. All species tested killed the insects at higher doses, with S. nepalensis and S. aureus being the most and least virulent, respectively. However, only S. nepalensis was able to kill more than 50% of larvae 72 h post-infection at a low amount of 105 CFU. Staphylococcus infection also stimulated an increase in the concentration of hemocytes present in the hemolymph, which was proportional to the virulence. To investigate T. molitor's suitability as an in vivo model for plasmid transfer studies, we used S. aureus strains as donor and recipient of a plasmid containing the gentamicin resistance gene aac(6')-aph(2″). By inoculating larvae with non-lethal doses of each, we observed conjugation, and obtained transconjugant colonies with a frequency of 1.6 × 10-5 per donor cell. This study demonstrates the potential of T. molitor larvae as a reliable and cost-effective model for analyzing the virulence of Staphylococcus and, for the first time, an optimal environment for the plasmid transfer between S. aureus carrying antimicrobial resistance genes.

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Methanolic stem bark extracts from ten Mexican Bursera Jacq. ex L. species were evaluated in vitro with regard to their inhibitory activity against two Tenebrio molitor-derived enzymes. Seven extracts (B. bicolor, B. copallifera, B. fagaroides, B. grandifolia, B. lancifolia, B. linanoe, and B. longipes) reduced α-amylase activity by 55.37% to 96.25%, with three samples proving to be particularly potent α-amylase inhibitors (B. grandifolia, B. lancifolia, and B. linanoe; IC50 = 162, 132, and 186 µg/mL, respectively). In contrast, no extract inhibited acetylcholinesterase activity by more than 39.94%. Quantitative HPLC analysis did not reveal any clear correlation between the species-specific flavonoid or phenolic acid profiles and the respective extracts' enzyme inhibitory activity. The findings reported herein do not only contribute to improving the current state of knowledge regarding the enzyme inhibitory potential of the Bursera genus, but could also lead to the development of new sustainable bioinsecticides.

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Sludge residue from pumping water treatment obtained by electrocoagulation process (LEC) in fishmeal factories, was used as a feeding ingredient for Tenebrio molitor larvae. LEC was conditioned by three bioprocesses: fermentation with Lactobacillus casei, fermentation with Sacharomyces, and hydrolysis with pancreatin enzymatic mixture. Soybean isolate was used as a control. Larvae consuming LEC-containing diets presented a higher weight gain rate than the controls. The proximal larvae dry basis composition values of fat, ash, and protein (37.2% ± 2%, 3.9% ± 0.4%, and 50.2% ± 4.9%, respectively) did not present significant intergroup differences. LEC contained 4.2% aluminum and its conditioning through fermentation with lactic bacteria reduced its bioavailability in the larvae, with values similar to those of controls (3.9 ± 0.7 µg Al/g). The iron content in LEC-fed larvae was higher than that in the control group, while their fatty acid profile was only slightly different. These initial results with LEC, which organic material is difficult to hydrate and assimilate, suggest its suitability as a protein source and attractant for a faster growth of T. molitor larvae.

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The objective of the present work was to optimize the microencapsulation conditions of neem (Azadirachta indica A. Juss) leaf extracts for the biocontrol of Tenebrio molitor. The complex coacervation method was used for the encapsulation of the extracts. The independent factors considered were the pH (3, 6, and 9), pectin (4, 6, and 8% w/v), and whey protein isolate (WPI) (0.50, 0.75, and 1.00% w/v). The Taguchi L9 (33) orthogonal array was used as the experimental matrix. The response variable was the mortality of T. molitor after 48 h. The nine treatments were applied by immersion of the insects for 10 s. The statistical analysis revealed that the most influential factor on the microencapsulation was the pH (73% of influence), followed by the pectin and WPI (15% and 7% influence, respectively). The software predicted that the optimal microencapsulation conditions were pH 3, pectin 6% w/v, and WPI 1% w/v. The signal-to-noise (S/N) ratio was predicted as 21.57. The experimental validation of the optimal conditions allowed us to obtain an S/N ratio of 18.54, equivalent to a T. molitor mortality of 85 ± 10.49%. The microcapsules had a diameter ranging from 1-5 µm. The microencapsulation by complex coacervation of neem leaf extract is an alternative for the preservation of insecticidal compounds extracted from neem leaves.

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The pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been responsible for approximately 6.8 million deaths worldwide, threatening more than 753 million individuals. People with severe coronavirus disease-2019 (COVID-19) infection often exhibit an immunosuppression condition, resulting in greater chances of developing co-infections with bacteria and fungi, including opportunistic yeasts belonging to the Saccharomyces and Candida genera. In the present work, we have reported the case of a 75-year-old woman admitted at a Brazilian university hospital with an arterial ulcer in the left foot, which was being prepared for surgical amputation. The patient presented other underlying diseases and presented positive tests for COVID-19 prior to hospitalization. She received antimicrobial treatment, but her general condition worsened quickly, leading to death by septic shock after 4 days of hospitalization. Blood samples collected on the day she died were positive for yeast-like organisms, which were later identified as Saccharomyces cerevisiae by both biochemical and molecular methods. The fungal strain exhibited low minimal inhibitory concentration values for the antifungal agents tested (amphotericin B, 5-flucytosine, caspofungin, fluconazole and voriconazole), and it was able to produce important virulence factors, such as extracellular bioactive molecules (e.g., aspartic peptidase, phospholipase, esterase, phytase, catalase, hemolysin and siderophore) and biofilm. Despite the activity against planktonic cells, the antifungals were not able to impact the mature biofilm parameters (biomass and viability). Additionally, the S. cerevisiae strain caused the death of Tenebrio molitor larvae, depending on the fungal inoculum, and larvae immunosuppression with corticosteroids increased the larvae mortality rate. In conclusion, the present study highlighted the emergence of S. cerevisiae as an opportunistic fungal pathogen in immunosuppressed patients presenting several severe comorbidities, including COVID-19 infection.

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The aim of this study was to evaluate the haematological and biochemical parameters of dogs submitted to different levels of inclusion of mealworm meal (0, 2.5, 5 and 7.5%) in their diet. Four adult females aged 5 years, castrated, with an average weight of 15.8 kg were used. A Latin square design was used, with 4 treatments and 4 replications. The base diets were calculated based on the NRC and provided in the proportion of 80% dry food and 20% wet food. The animals were dewormed, clinically evaluated and adapted to the base diet for 10 days prior to the insertion of me. After fitting, blood was collected for evaluation of haematological and biochemical parameters. The experimental period of each treatment was 14 days, with a new blood collection on the 15th day, with the animals in the fasted state. The blood parameters evaluated were blood count and biochemical tests, composed of urea, creatinine, alanine aminotransferase, alkaline phosphatase, cholesterol, total proteins and their fractions, glucose, triglycerides, C-reactive protein, fibrinogen and immunoglobulin E. The data obtained were subjected to multiple analysis of variance at the 5% significance level. The results showed that none of the mealworm protein inclusion levels showed blood alterations. Therefore, it can be concluded that the use of mealworm meal did not harm the health of the animals tested in experiment, showing that it can be an alternative protein source and can be safely included up to a level of 7.5% in dog foods

O estudo objetivou-se avaliar os parâmetros hematológicos e bioquímicos de cães submetidos à diferentes níveis de inclusão da farinha da larva de Tenebrio molitor (0%, 2,5%, 5% e 7,5%) à sua dieta. Foram utilizadas 4 fêmeas adultas com 5 anos, castradas, peso médio de 15,8kg. Utilizou-se o delineamento em quadrado latino, com 4 tratamentos e 4 repetições. As dietas bases foram calculadas com base no NRC e fornecidas na proporção de 80% de alimento seco e 20% de alimento úmido. Os animais foram desverminados, avaliados clinicamente e adaptados à dieta base por 10 dias que antecederam a inserção da farinha dde Tenebrio. Após a adaptação coletou-se sangue para a avaliação dos parâmetros hematológicos e bioquímicos. O período experimental de cada tratamento foi de 14 dias, havendo nova coleta sanguínea no décimo quinto dia, com os animais em jejum. Os parâmetros sanguíneos avaliados foram hemograma, e exames bioquímicos, compostos por ureia, creatinina, alanina aminotransferase, fosfatase alcalina, colesterol, proteínas totais e suas frações, glicose, triglicérides, proteína C reativa, fibrinogênio e imunoglobulina E. Os dados obtidos foram submetidos à análise de variância múltipla a 5% de significância. Os resultados demonstraram que, em nenhum dos níveis de inclusão da proteína de tenébrio houveram alterações sanguíneas. Portanto, concluir-se que o uso da farinha de Tenebrio molitor não apresentou prejuizos a saude dos animais testados neste experimento, evidenciando que pode ser uma fonte proteica alternativa e ser seguramente incluída até o nível de 7,5% em alimentos para cães

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This study aimed to evaluate the effects of dietary supplementation pelleted Tenebrio molitor (TM) powder with chokeberry by-product (CBP) meal on duck production and meat quality traits. A total of 180 0-day-old Pekin ducks were allocated randomly between three dietary groups viz., control, Treatment 1, and Treatment 2, with three pens per group and twenty birds per pen, characterized by increasing levels of pelleted TM powder with CBP meal in concentration of 0%, 1.5%, and 3%, respectively, and reared until 42 days of age in a completely randomized design. On day 42, the ducks were sacrificed, and breast and thigh muscles were used for meat quality evaluations. Feeding pelleted TM powder with CBP meal resulted in a significant difference in final body weight, weight gain and feed conversion ratio (p<0.05). Additionally, a significant difference was observed in the pH of the breast meat samples (p<0.05). As the only significant difference between the breast and thigh meat, 1,1-diphenyl-2-picryhydrazyl radical scavenging was influenced significantly by the dietary inclusion of pelleted TM powder with CBP meal (p<0.05). However, the values of thiobarbituric acid reactive substances and meat color in both breast and thigh meat were insignificant (p>0.05) different among all groups. To conclude, the inclusion of up to 3 % of pelleted TM powder with CBP meal in the diets of ducks did improve the growth production and antioxidant characteristics effects, which could decrease TBARS and reflected by changes in 1,1-diphenyl-2- picrylhydrazyl free DPPH radical scavenging values.(AU)

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Candida albicans is a human pathogen that is part of the healthy microbiome. However, it is often associated with opportunistic fungal infections. The treatment of these infections is challenging because prolonged exposure to antifungal drugs can culminate in fungal resistance during therapy, and there is a limited number of available drugs. Therefore, this study investigated the antifungal activity of ononin by in silico and in vitro assays, and in Tenebrio molitor as an alternative in vivo model of infection caused by C. albicans. Ononin is an isoflavone glycoside derived from formononetin that has various biological activities. According in silico evaluation, ononin showed the best electron affinity in molecular docking with CaCYP51, with a binding free energy of -10.89 kcal/mol, superior to that of the antifungal drugs fluconazole and posaconazole. The ononin + CaCYP51 complex formed hydrogen bonds with Tyr132, Ser378, Phe380, and Met508, as well as hydrophobic connections with Tyr118, Leu121, Phe126, Leu131, Ile304, and Leu309, and interactions with the heme group. Ononin exerted anti-Candida albicans activity, with MIC between 3.9 and 7.8 µg/mL, and inhibited young and mature biofilms, with a reduction in cell density and metabolic activity of 50 to 80%. The compound was not cytotoxic to sheep red blood cells at concentrations up to 1000 µg/mL. Larvae of the mealworm T. molitor were used as an alternative in vivo model of C. albicans infection. Ononin was able to prolong larval survival at concentrations of 0.5, 1, and 5 mg/kg, and was not toxic up to a concentration of 20 mg/kg. Moreover, ononin reduced the fungal charge in treated animals. In conclusion, our results suggest that ononin has anti-Candida albicans activity and is a potential candidate for the development of new therapeutic alternatives.