ABSTRACT: The white mulberry leaves are typically available on the market in dried or encapsulated form. It was assumed in the study that appropriate drying of leaves of the white mulberry is significant for obtaining intermediate products with high content of compounds having anti-oxidative activity. The purpose of the study was to determine the influence of the temperature of mulberry leaves air drying on the content of phenolic acids and flavonols. It has been determined that the content of these compounds in the leaves depended on the drying temperature. Drying at 60 °C favored release of phenolic acids and flavonols from complexes and/or formation of new compounds. Their total content was 22% higher than in leaves dried at 30 °C. Drying at 90 °C reduced the phenolic acid and flavonol content by 24%. The most favorable drying temperature was 60 °C.
RESUMO: As folhas da amoreira branca estão normalmente disponíveis no mercado em forma seca ou encapsulada. Assumiu-se no estudo que a secagem adequada das folhas da amora branca é importante para a obtenção de produtos intermediários com alto teor de compostos com atividade antioxidante. O objetivo do estudo foi determinar a influência da temperatura de secagem de ar de folhas de amoreira sobre o teor de ácidos fenólicos e flavonóis. Foi determinado que o conteúdo destes compostos nas folhas dependia da temperatura de secagem. Secagem a 60 °C favoreceu a liberação de ácidos fenólicos e flavonóis a partir de complexos e / ou formação de novos compostos. Seu teor total foi 22% superior ao das folhas secas a 30 °C. A secagem a 90 °C reduziu o teor de ácido fenólico e flavonol em 24%. A temperatura de secagem mais favorável foi de 60 °C.
Presence of fungi in food and feed products is a major problem. Fungi synthesize a large number of secondary metabolites including particularly harmful mycotoxins. They can be produced in plant tissues and are commonly found all over the world in many products including cereals. A total of 44 samples were taken for identification of ergosterol - the potential marker of fungal presence. Fourteen of these samples were chosen for further studies that included the evaluation of the relationship between ergosterol content and three major mycotoxins produced by Fusariumspp.: fumonisin B1, zearalenone and deoxynivalenol. Fungal strains were also isolated and identified by molecular means in those samples. The results of the studies give a further and more detailed insight into the relationship between contents of ergosterol and mycotoxins in different cereal products. It was found that there was no correlation between content of ergosterol and mycotoxins in the tested food products. Also, the presence of mycotoxins was not correlated with occurrence of species able to produce these toxins.