Dayane Lilian Gallani Silva

Resumo A resistência antimicrobiana em cepas de Escherichia coli tem contribuído para a busca por produtos alternativos ao seu uso, como os extratos vegetais. O objetivo deste estudo foi avaliar o perfil dos genes de resistência a cefalosporinas em isolados de E. coli com fenótipo de produção de beta-lactamase de espectro estendido (ESBL), a composição fenólica e a atividade antibacteriana do extrato etanólico de Pereskia aculeata contra cepas isoladas de frangos de um dia de vida e em crescimento. Para determinar a Concentração Inibitória Mínima (CIM) e a Concentração Bactericida Mínima (CBM) do extrato etanólico de P. aculeata, foram selecionados isolados de E. coli que apresentaram perfil ESBL em uma das origens (pintos de um dia ou frangos em crescimento). Os genes de resistência blaCTX-M-1, blaCTX-M-2, blaCTX-M-8 e blaSHV foram detectados com maior percentual em isolados de frangos em crescimento. O extrato de P. aculeata apresentou diversos compostos fenólicos, sendo o ácido málico e a rutina os predominantes. A determinação da CIM foi possível em apenas dois isolados de E. coli, um do Aviário A (frangos em crescimento) e outro do Aviário B (pintos de um dia). Em ambos os casos, a CIM foi de 20 mg/mL. Na cepa ATCC 25922 de E. coli, utilizada como cepa padrão para a avaliação do teste, a CIM foi de 20 mg/mL. Conclui-se que isolados de E. coli provenientes de pintos de um dia e frangos em crescimento carregam genes de resistência a cefalosporinas, e que não há diferença na CIM do extrato etanólico de P. aculeata Mill. quando comparadas cepas com perfil fenotípico ESBL àquelas que não apresentam esse perfil, demonstrando a necessidade de estudos adicionais com plantas com potencial antimicrobiano.

Antimicrobial resistance in Escherichia coli strains has contributed to the search for alternative antimicrobial products, such as plant extracts. The objective of this study was to evaluate the profile of cephalosporin-resistance genes in E. coli isolates with an extended-spectrum ß-lactamase (ESBL) production phenotype, and the phenolic composition and antibacterial activity of the ethanolic extract of Pereskia aculeata against strains isolated from 1-day-old and growing chickens. To determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the ethanolic extract of P. aculeata, E. coli isolates that exhibited an ESBL profile when isolated from either 1-day-old chicks or growing chickens were selected. The resistance genes blaCTX-M-1, blaCTX-M-2, blaCTX-M-8, and blaSHV were detected in a higher percentage of isolates from growing chickens. The P. aculeata extract was found to contain several phenolic compounds, with malic acid and rutin being predominant. Determination of MIC was only possible for two E. coli isolates (one from Broiler house A (growing chickens) and the other from Broiler house B (1-day-old chicks) - and for the standard strain E. coli ATCC 25922; in all cases, the MIC was 20 mg/mL. These findings indicate that E. coli isolates from both age groups carried cephalosporin-resistance genes and exhibit similar susceptibility to the P. aculeata extract, regardless of ESBL phenotype. These results highlight the need for further research into plant-based antimicrobials.

The aim of this study was to develop and characterize reduced-fat ice cream formulations with the addition of dehydrated cassava bagasse (CB) and lychee pulp (LP). The ice cream formulations were prepared with different proportions of palm fat (0 to 5%), CB (0 to 5%) and LP (1 to 8%) and were evaluated in terms of chemical and microbiological composition, and in relation to the technological, antioxidant and sensory properties. The use of higher levels of CB (5%) and LP (8%) allowed obtaining a higher fiber content and lower fat content, and all formulations were safe for consumption, and it was noted adequate values for overrun, melting rate and color. The ice creams showed adequate sensory acceptance, with emphasis on the formulations containing different amounts of CB addition (2 to 5%) and 2% LP. The higher LP content the higher total phenolic content and the antioxidant capacity were found in ice cream formulations. These results showed the viability of applying CB and LP in ice cream formulations, promoting the sustainability by using a natural source of antioxidants and a fiber-rich agro-industrial by-product.

O Brasil é o maior produtor mundial de cana-de-açúcar, sendo assim o objetivo deste trabalho foi apresentar os impactos econômicos, sociais e ambientais do seu cultivo além de mostrar algumas aplicações dos subprodutos gerados no processo de produção com enfoque na sustentabilidade do setor. Para tanto, a metodologia utilizada foi a revisão da literatura disponível em quatro bases de dados: Scielo, CAPES, Science Direct e Google Scholar sobre o tema. Percebe-se que a indústria sucroalcooleira produz um impacto tanto no setor econômico, social e ambiental. Os subprodutos oriundos do processamento quando bem utilizados podem promover lucros, diminuição dos problemas ambientais e geração de emprego e renda. Porém, é necessário grande investimento tanto do setor público e privado em tecnologias e pesquisas acadêmicas, pois, a utilização dos subprodutos é altamente promissora para o desenvolvimento sustentável permitindo a correta destinação dos resíduos gerados, conduzindo ao caminho promissor do desenvolvimento sustentável.

Fungal cocultures can promote complex interactions that result in physiological and biochemical alterations that favor the synergic and more efficient action of extracellular enzymes such as laccase. Thus, coculture can be used as a strategy to increase enzymatic activity, dye degradation, and bioremediation of textile effluents. This study aimed to evaluate the coculture effect of Lentinus crinitus, Pleurotus ostreatus, Pycnoporus sanguineus, and Trametes polyzona on laccase activity, mycelial biomass production, and in vitro decolorization of azo, anthraquinone, and triphenylmethane dyes. The species were cultivated in liquid medium in monoculture and coculture in paired combinations for 15 days to determine the laccase activity and produced mycelial biomass. The enzymatic extracts of fungal cultivations were used in decolorization tests of reactive blue 220 (RB220), malachite green (MG), and remazol brilliant blue R (RBBR). Pleurotus-Trametes, Lentinus-Pleurotus, and Lentinus-Trametes cocultures increase laccase activity compared to respective monocultures. Lentinus-Pycnoporus, Lentinus-Trametes, Lentinus-Pleurotus, and Pleurotus-Trametes cocultures stimulate mycelial biomass production in relation to their respective monocultures. The enzymatic extracts of monocultures and cocultures promoted the decolorization of all dyes. RB220 dye presented fast decolorization. In 24 h, all extracts reached maximum decolorization and the greatest color reduction percentage was 90% for Pleurotus-Trametes coculture extract. Pleurotus-Trametes extract also increased the decolorization of MG and RBBR dyes when compared to their respective monocultures in 48 h and 72 h, respectively. However, RBBR dye presented the greatest resistance to decolorization.