Scorpionicidal activity of secondary metabolites from Paecilomyces sp. CMAA1686 against Tityus serrulatus.

Introduction: Urban pests pose enormous risks to human health. Control initiatives are carried out in regions of high infestation and incidence of accidents caused by scorpions OBJECTIVE: In this study, we aimed to analyze the anti-scorpionic activity of fungal isolates obtained from a cemetery in Brazil.

Materials And Methods: A total of thirteen fungi were subjected to a bioassay test against Tityus serrulatus, and the two isolates with the highest scorpionicidal activity were selected for molecular identification through sequencing of the ITS DNA hypervariable region and large-scale cultivation on liquid medium for secondary metabolite extraction.

YTOX: a rapid toxicity test based on the dehydrogenase activity of Saccharomyces cerevisiae for detection of contaminants in water samples.

A simple generic toxicity method (test) is proposed using baker's yeast to mediate the reduction of the colourless triphenyltetrazolium chloride (TTC) to red, 1,3,5-triphenyl formazan, which can be extracted by dimethyl sulfoxide (DMSO), enabling the identification of reducible toxic compounds (e.g. cadmium, fipronil) in water for consumption.

Sulphate production by Paracoccus pantotrophus ATCC 35512 from different sulphur substrates: sodium thiosulphate, sulphite and sulphide.

One of the problems in waste water treatment plants (WWTPs) is the increase in emissions of hydrogen sulphide (H2S), which can cause damage to the health of human populations and ecosystems. To control emissions of this gas, sulphur-oxidizing bacteria can be used to convert H2S to sulphate. In this work, sulphate detection was performed by spectrophotometry, ion chromatography and atomic absorption spectrometry, using Paracoccus pantotrophus ATCC 35512 as a reference strain growing in an inorganic broth supplemented with sodium thiosulphate (Na2S2O3·5H2O), sodium sulphide (Na2S) or sodium sulphite (Na2SO3), separately.