Abstract The species Waltheria viscosissima A.St.–Hil, Malvaceae, which is known as ‘malva-branca', is traditionally used in the Brazilian northeast for the treatment of coughs. This research looks towards reporting the isolation of phytoconstituents of W. viscosissima, as well as the quantification of its phenolics, total flavonoid content, and free radical scavenging potential, along with an evaluation of its larvicidal activity against Aedes aegypti larvae. Chromatographic techniques were used to isolate the compounds and a structural elucidation was performed by 1D and 2D NMR. The quantification of total phenolics and flavonoids and the DPPH˙ radical scavenging activity was determined through spectrophotometric methods. Consequently, the phytochemical investigation led to the identification of fourteen compounds from the aerial parts of the W. viscosissima: steroids, triterpenes, alkaloids, and eight flavonoids previously reported in the literature. The quantification of compounds showed that the aerial parts extract possessed high concentration of flavonoids, while the roots extract were rich in other phenolic compounds. At the DPPH˙ free radical scavenging assay, the roots extract presented EC50 = 77.32 ± 4.37 µg/ml and the aerial parts extracts showed EC50 = 118.10 ± 1.21 µg/ml. W. viscosissima roots extract showed the most potent larvicidal activity against Ae. aegypti (LC50 = 4.78 mg/ml), with the potential of being used in effective and economically viable preparations that can be catered for domestic use towards controlling the vector insect of severe diseases, such as dengue and Zika.

Durante o processo de resfriamento dos ovos embrionados, há um fluxo natural de ar da superfície para o interior dos ovos carreando contaminantes como bactérias e fungos, por meio dos poros da casca, infectando o embrião e resultando na inabilidade para eclodir e pintinhos de má qualidade. O formaldeído que é um produto tóxico ainda é o desinfetante mais utilizado para a desinfecção de ovos embrionados pela indústria avícola. Para avaliar a atividade antimicrobiana do extrato etanólico da própolis verde, como alternativa ao formaldeído, foram coletados 140 ovos de ninhos de matrizes de frango de corte submetidos à desinfecção com cinco tratamentos: T1 - sem desinfecção; T2 - ovos fumigados com formaldeído; T3, T4 e T5 desinfetados por imersão com solução de própolis nas concentrações de 2.400 µg, 240 µg e 24 µg, respectivamente. Os níveis de contaminação da casca dos ovos por mesófilos totais e fungos (Aspergillus e outros bolores), após a desinfecção com própolis, foram menores quando comparados ao controle. Na comparação ao tratamento com formaldeído as concentrações de própolis com 240 µg e 24 µg não diferiram para atividade antibacteriana, já para atividade antifúngica, 2,4 mg e 240 µg foram superiores. Com relação à eclodibilidade dos ovos, após 21 dias de incubação, os tratamentos de própolis (2,4 mg e 240 µg) apresentaram as maiores taxas com 94,11% superando o tratamento com formaldeído. Portanto, o extrato etanólico de própolis verde apresenta atividade antibacteriana e antifúngica em ovos embrionados podendo ser um novo produto natural desinfetante em substituição ao formaldeído.

During the cooling process of embryonated eggs, there is a natural air flux from the surface to the inner part of the eggs, carrying contaminants such as bacteria and fungi through the shell's pores, infecting embryos and resulting in the inability to hatch or poor chick quality. Formaldehyde, a toxic product, is still the most used disinfectant for embryonated eggs in the aviculture industry. In order to evaluate the antimicrobial activity of the green propolis ethanolic extract as an alternative to formaldehyde, 140 hatching eggs from laying hens were collected and submitted to disinfection with five different treatments: T1 - without disinfection; T2 - formaldehyde fumigated eggs; T3, T4 and T5 disinfection by immersion in propolis solution in the concentrations of 2,400 µg, 240 µg and 24 µg, respectively. The contamination levels by total mesophiles and fungi of the egg shells (Aspergillus sp. and other moulds) after disinfection with propolis were lower than when compared to the control without disinfection. In comparison with formaldehyde, the 240 µg and 24 µg propolis concentrations did not differ regarding antibacterial activity, but for antifungal activity the 2,400 µg and 240 µg concentrations were more efficient. The 2,400 µg and 240 µg propolis treatments presented a hatching rate of 94.1%, compared to only 84.6% for the formaldehyde treatment. The green propolis ethanolic extract presented antibacterial and antifungal activities in embryonated eggs showing that it can be a new natural disinfectant product substituting formaldehyde.