Combining high intensity ultrasound and experimental design to improve carotenoid extraction efficiency from Buriti (Mauritia flexuosa).

Buriti (Mauritia flexuosa L.) is a significant source of carotenoids, but these compounds have been extracted using laborious and low-effective methods. The present work evaluated the high-intensity ultrasound combined with a chemometric approach to developing an optimal extraction method of carotenoids from buriti pulp. The multivariate optimization was carried out through two steps. First, a simplex-lattice mixture design was used to optimize the extractor solution finding higher extraction yield (903 ± 21 µg g-1) with the acetone:ethanol (75/25) mixture. After, sample mass (80 mg) and sonication time (30 min) were optimized applying central composite design (CCD) which provided a 14% improvement in the extraction method yield. So, the total carotenoid content (TCC) with optimal extraction conditions was 1026 ± 13 µg g-1which is almost twice the yield of methods known in the literature for buriti. The RP-HPLC-DAD analysis revealed that the carotenoids are gently extracted and ß-carotene is the major compound in the extracts. To confirm the accuracy, buriti samples spiked with ß-carotene standard and the developed method showed recovery >84% and precision <6.5%. Furthermore, the optimized ultrasound-assisted extraction (UAE) method was applied to other samples (tomato, guava, carrot, mango, acerola, papaya, and pumpkin) and presented a yield to 5.5-fold higher when compared to the reported methods indicating high robustness. Based on results, the UAE method developed has demonstrated feasibility and reliability for the study of carotenoids in buriti pulp as well as in other plant matrices with high biological relevance.

Multivariate optimization and comparison between conventional extraction (CE) and ultrasonic-assisted extraction (UAE) of carotenoid extraction from cashew apple.

Carotenoids are an essential component of cashew and can be used in pharmaceuticals, cosmetics, natural pigment, food additives, among other applications. The present work focuses on optimizing and comparing conventional and ultrasound-assisted extraction methods. Every optimization step took place with a 1:1 (w:w) mixture of yellow and red cashew apples lyophilized and ground in a cryogenic mill. A Simplex-centroid design was applied for both methods, and the solvents acetone, methanol, ethanol, and petroleum ether were evaluated. After choosing the extractor solvent, a central composite design was applied to optimize the sample mass (59-201 mg) and extraction time (6-34 min). The optimum conditions for the extractor solvent were 38% acetone, 30% ethanol, and 32% petroleum ether for CE and a mixture of 44% acetone and 56% methanol for UAE. The best experimental conditions for UAE were a sonication time of 19 min and a sample mass of 153 mg, while the CE was 23 min and 136 mg. Comparing red and yellow cashews, red cashews showed a higher carotenoid content in both methodologies. The UAE methodology was ca. 21% faster, presented a more straightforward composition of extracting solution, showed an average yield of superior carotenoid content in all samples compared to CE. Therefore, UAE has demonstrated a simple, efficient, fast, low-cost adjustment methodology and a reliable alternative for other applications involving these bioactive compounds in the studied or similar matrix.

Avaliação dos parâmetros de dureza, condutividade e sólidos totais das águas de abastecimento de escolas públicas do município de Teresina-PI / Evaluation of the parameters of hardness, conductivity and total solids of the waters of the public schools of the Teresina-PI municipality

A avaliação de parâmetros físico-químicos fornece uma ideia da qualidade da água das escolas de um determinado local. Desta forma, objetivou-se com este trabalho caracterizar as amostras de águas de abastecimento de escolas públicas no município de Teresina-PI, por meio das análises de dureza, condutividade e sólidos totais dissolvidos. As coletas de água foram realizadas em cinco escolas (Zonas Sul, Sudeste, Leste, Norte e Centro) e coletadas 42 amostras de águas no total. Os referidos parâmetros foram avaliados conforme o prescrito pela APHA. Os resultados revelaram que a água fornecida pelas escolas aos alunos apresenta-se em conformidade com os padrões, exceto um ponto de coleta (zona centro) apresentou valores de condutividade e dureza alterados.

Avaliação dos parâmetros de pH, turbidez e alcalinidade das águas de abastecimento de escolas públicas do município de Teresina-PI / Evaluation of the pH, turbidity and alkalinity parameters of the waters of public schools of integral times of the Teresina-PI municipality

O monitoramento da qualidade da água destinada ao consumo humano é imprescindível. Desta forma, objetivou-se com este trabalho caracterizar as amostras de águas de abastecimento de escolas públicas de tempo integral no município de Teresina-PI, por meio das análises de pH, turbidez e alcalinidade. As coletas de água foram realizadas em cinco escolas (zonas Sul, Sudeste, Leste, Norte e Centro) da cidade de Teresina - PI. Foram coletadas durante três meses, perfazendo 42 amostras de águas no total. As análises foram efetuadas conforme os métodos prescritos pela APHA. Os parâmetros pH, alcalinidade e turbidez das amostras coletadas em escolas de diferentes zonas da cidade de Teresina – PI, encontram-se conforme o estabelecido pelos padrões de potabilidade da Portaria nº 2.914/2011.

Avaliação dos parâmetros microbiológicos das águas de bebedouros de escolas públicas de diferentes zonas do município de Teresina-PI / Evaluation of the microbiological parameters of the waters of public schools before different areas of the Teresina-PI municipality

A água potável não deve conter microorganismos patogênicos e deve estar livre de bactérias indicadoras de contaminação fecal. Desta forma, objetivou-se avaliar o perfil microbiológico das águas de bebedouros de escolas públicas de diferentes zonas do município de Teresina-PI. Foram coletadas 42 amostras durante um período de 3 meses em águas de bebedouros de escolas das zonas Sul, Sudeste, Leste, Norte e Centro da cidade de Teresina - PI. A determinação de coliformes totais e Escherichia coli foi realizada seguindo os métodos prescritos pela APHA. Diante dos resultados obtidos, observou-se que a totalidade de 42 amostras coletadas em escolas de diferentes zonas da cidade de Teresina - PI, apresentaram ausência para coliformes totais e Escherichia coli.