Analysis of triazines, triazoles, and benzimidazoles used as pesticides in different environmental compartments of the Formoso River and their influence on biodiversity in Tocantins.

Considering the increase in agricultural production in Tocantins and in the use of pesticides for such production, this work investigates the levels of pesticide residues in different environmental compartments (soil, sediment, and water samples) of the Formoso River in the state of Tocantins, Brazil. The presence of pesticides of the triazine, triazole, and benzimidazole classes was analyzed by UHPLC-MS/MS from April 2018 to February 2019. There were four quarterly collections in the dry and rainy periods. The active principles were not found in sediment samples. In soil samples, only the active ingredients tebuconazole and propiconazole were found in the third collection campaign. The active ingredients amethryn, atrazine, carbendazim, epoxiconazole, metconazole, propiconazole, simazine, tebuconazole, and tetraconazole were found in water samples from Formoso River at concentrations of up to 0.286 µg L-1 (atrazine). Although the substances are in low concentrations, we cannot assume that this toxicity is low considering that the risk of a certain pesticide depends on levels and exposure time. Therefore, the action of substances external to the natural environment always threatens biodiversity.

ß-Fructofuranosidase and ß -D-Fructosyltransferase from New Aspergillus carbonarius PC-4 Strain Isolated from Canned Peach Syrup: Effect of Carbon and Nitrogen Sources on Enzyme Production.

ß-fructofuranosidase (invertase) and ß-D-fructosyltransferase (FTase) are enzymes used in industrial processes to hydrolyze sucrose aiming to produce inverted sugar syrup or fructooligosaccharides. In this work, a black Aspergillus sp. PC-4 was selected among six filamentous fungi isolated from canned peach syrup which were initially screened for invertase production. Cultivations with pure carbon sources showed that invertase and FTase were produced from glucose and sucrose, but high levels were also obtained from raffinose and inulin. Pineapple crown was the best complex carbon source for invertase (6.71 U/mL after 3 days of cultivation) and FTase production (14.60 U/mL after 5 days of cultivation). Yeast extract and ammonium chloride nitrogen sources provided higher production of invertase (6.80 U/mL and 6.30 U/mL, respectively), whereas ammonium nitrate and soybean protein were the best nitrogen sources for FTase production (24.00 U/mL and 24.90 U/mL, respectively). Fermentation parameters for invertase using yeast extract were Y P/S = 536.85 U/g and P P = 1.49 U/g/h. FTase production showed values of Y P/S = 2,627.93 U/g and P P = 4.4 U/h using soybean protein. The screening for best culture conditions showed an increase of invertase production values by 5.10-fold after 96 h cultivation compared to initial experiments (fungi bioprospection), while FTase production increased by 14.60-fold (44.40 U/mL) after 168 h cultivation. A. carbonarius PC-4 is a new promising strain for invertase and FTase production from low cost carbon sources, whose synthesized enzymes are suitable for the production of inverted sugar, fructose syrups, and fructooligosaccharides.