The larvicidal effect of the supernatant of Lactobacillus acidophilus ATCC 4356 on Toxocara canis.

Human toxocariasis is a parasitic anthropozoonosis that is difficult to treat and control. A previous study carried out with Lactobacillus acidophilus ATCC 4356 revealed that the cell free supernatant (CFS) of this probiotic killed 100% of Toxocara canis larvae in vitro. The present study aimed to investigate the characteristics of the CFS of L. acidophilus ATCC 4356, which may be involved in its larvicidal effects on T. canis. L. acidophilus ATCC 4356 was cultured, and lactic and acetic acids present in the CFS were quantified by high performance liquid chromatography (HPLC). The levels of pH and H2O2 were also analyzed. To assess the larvicidal effect of the CFS, this was tested pure and diluted (1:2 to 1:128) on T. canis larvae. High concentrations of lactic and acetic acids were detected in the CFS. The acidity of the pure CFS was observed at pH 3.8, remaining acidic at dilutions of 1:2 to 1:16. Regarding the in vitro larvicidal effect, 100% death of T. canis larvae was observed using the pure CFS and 1:2 dilution. Based on these results, it can be inferred that the presence of higher concentrations of organic acids and low pH of the medium contributed to the larvicidal activity of the CFS of L. acidophilus ATCC 4356. In addition, the maintenance of the larvicidal effect, even after dilution, suggests a greater chance of the larvicidal effect of this CFS against T. canis in vivo.

Polycyclic Aromatic Hydrocarbons (PAHs) in honey from stingless bees (Meliponinae) in southern Brazil.

This study evaluated sixteen Polycyclic Aromatic Hydrocarbons (PAHs) considered priority pollutants by the United States Environmental Protection Agency (USEPA) in 13 honey samples from seven Meliponinae species, collected in native forests and industrial areas in southern Brazil. All samples contained at least one PAH. ∑PAHs ranged from 1.4 to 23.3 µg kg-1, where 23 % of samples were above the maximum allowed levels in dietary food for special medical purposes. Furthermore, the Excess Cancer Risk (ECR) ranged from 1.67 × 10-5 to 6.17 × 10-3, and 2.97 × 10-6 to 1.10 × 10-3, according to the Brazilian Institute of Geography and Statistics (IBGE) and Food and Agriculture Organization (FAO) daily intakes, respectively, being 61.54 % and 15.38 % of the samples above the threshold classified into sever by the USEPA. Results highlighted that honey has been affected by PAH contamination and that it has the potential to be used as an indicator of environmental pollution.

Meliponinae and Apis mellifera honey in southern Brazil: Physicochemical characterization and determination of pesticides.

This study evaluated the physicochemical parameters and the occurrence of pesticides in multi-flower honey produced by six species of Meliponinae and Apis mellifera and collected in different seasons, floral species and sites in southern Brazil. Meliponinae honey were found to exhibit higher moisture, free acidity and sucrose concentration and lower concentration of reducing sugars than the standard of Apis mellifera honey in Brazil. Regarding Apis mellifera honey, reducing sugars and sucrose did not comply with the legislation. The Principal Component Analysis (PCA) showed that most of the composition variability was defined by free acidity, moisture, soluble solids, fructose, glucose, and reducing sugars. Determination of pesticides was carried out by the citrate QuEChERS method and gas chromatography tandem mass spectrometry (GC-MS/MS). However, no pesticide residues at concentrations above the limit of quantification were found in the twenty honey samples. Results show that this region has the potential to produce honey.

Fast and simple method of simultaneous preservative determination in different processed foods by QuEChERS and HPLC-UV: Method development, survey and estimate of daily intake.

A fast and simple method, which employs QuEChERS and HPLC-UV, was developed to determine preservatives in processed foods from different classes. The method showed correlation coefficients above 0.99, LOQs between 0.13 and 0.33 mg kg-1 and recoveries between 91 and 107%, with RSD ≤ 5.3%. Levels of preservatives were up to 2040 mg kg-1 for benzoates, up to 3185 mg kg-1 for sorbates and up to 452 mg kg-1 for methylparaben. Only four out of 82 samples under analysis were above the maximum level allowed by the legislation. Additionally, daily intakes of preservatives were estimated. Regarding benzoates, relatively high intakes were estimated (25% of the acceptable daily intake - ADI) in comparison with sorbates (5% of ADI) and parabens (<1% of ADI), when mean consumption is considered. This method is a good alternative to determining preservatives in different food samples.

Antifouling booster biocides in coastal waters of Panama: First appraisal in one of the busiest shipping zones.

A baseline study for antifouling booster biocides in coastal waters of Panama is presented. Solid Phase Extraction (SPE) was used for extraction and Liquid Chromatography tandem Mass Spectrometry (LC-MS/MS) was applied for the quantification of irgarol 1051, diuron, (2-thiocyanomethylthio)benzothiazole (TCMTB), 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one (DCOIT) and dichlofluanid. TCMTB, DCOIT and dichlofluanid were not detected in any seawater sample, while irgarol 1051 and diuron were found in four out of thirteen areas (<0.3 to 5.0ngL-1 and <2.7 to 70ngL-1, respectively). Although the hotspots were identified in areas influenced by marinas and in one of the ports, diuron and irgarol 1051 levels were all lower than the threshold levels set by the Environmental Quality Standard of United Kingdom. However, this is only a snapshot of the status of costal water contamination by antifouling booster biocides and a more comprehensive assessment is needed to assess risks associated to long term exposure.

New environmentally friendly MSPD solid support based on golden mussel shell: characterization and application for extraction of organic contaminants from mussel tissue.

The use of golden mussel shells as a solid support in vortex-assisted matrix solid-phase dispersion (MSPD) was evaluated for the first time for extraction of residues of 11 pesticides and nine pharmaceutical and personal care products from mussel tissue samples. After they had been washed, dried, and milled, the mussel shells were characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy, infrared spectroscopy, and Brunauer-Emmett-Teller analysis. The MSPD procedure with analysis by liquid chromatography-tandem mass spectrometry allowed the determination of target analytes at trace concentrations (nanograms per gram), with mean recoveries ranging from 61 to 107 % and relative standard deviations lower than 18 %. The optimized method consisted of dispersion of 0.5 g of mussel tissue, 0.5 g of NaSO4, and 0.5 g of golden mussel shell for 5 min, and subsequent extraction with 5 mL of ethyl acetate. The matrix effect was evaluated, and a low effect was found for all compounds. The results showed that mussel shell is an effective material and a less expensive material than materials that have traditionally been used, i.e., it may be used in the MSPD dispersion step during the extraction of pesticides and pharmaceutical and personal care products from golden mussel tissues. Graphical Abstract Vortex-assited matrix solid-phase dispersion for extraction of 11 pesticides and 9 PPCPs care products from mussel tissue samples.