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With COVID-19, there has been an increase in the use of gelling agents for hand sanitizer production, and as a result, the release of this product into wastewater could induce impacts and adverse reactions in living organisms. Thus, ecotoxicological and cytotoxicological assessments of gelling agents with test organisms from different trophic levels are necessary to assess their environmental safety. For this, seven cellulose-based gelling agents and a polyacrylic acid derivative (C940) were selected for tests with Artemia salina. The most toxic agent was tested on Allium cepa to assess cytotoxicity. The volatile compounds of the gelling agents were analyzed. Cellulose-based gelling agents were not considered toxic according to their LC 50 , but C940 presented moderate toxicity to A. salina and cytotoxicity to Allium cepa, but without mutagenicity. In addition, C940 contained cyclohexane as a volatile compound. Thus, cellulose-based gelling agents are better environmental options than carbomer for 70% alcohol gel sanitizer., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

The present study reports the development of a bioassay using Artemia spp. to analyse the preliminary ecotoxicity of atmospheric aerosols (PM), which can affect the environment and human health. Herein, PM samples were collected in the city of Goiânia (Brazil) in 2016, extracted with ultrapure water and subsequently filtered through membranes with different pore sizes (100, 0.8, and 0.22 μm), and the extracts employed in the bioassays. The mortality rates (endpoint analysed) declined to membranes with smaller pore sizes (15 ± 4%, 47 ± 10% and 43 ± 9% for pore sizes of 100 μm, 0.8 μm and 0.22 μm, respectively). In general, the toxicity of the extract depended on its concentration, except for the sample with a higher negative particle surface charge, which presents a lower affinity for the negatively charged surfaces of cellular membranes. Moreover, although the PM concentration was higher for the sample collected during the dry season (September), the mortality rate was not significantly different to that determined for a sample with similar physical and chemical characteristics collected in the rainy season (December). This result demonstrates the importance of monitoring PM toxicities and their chemical and physical characteristics, in addition to their concentrations. Therefore, the new protocol to provide a preliminary analysis of the toxicity of the extracts of aerosol emerges as a useful, accessible, and fast tool for monitoring possible environmental hazards, and can simplify fieldwork., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Biofuels are expected to play a major role in reducing carbon emissions in the aviation sector globally. Farnesane ("2,6,10-trimethyldodecane") is a biofuel derived from the synthesized iso-paraffin route wich can be blended with jet fuel; however, the microbial behavior in farnesane/jet fuel blends remains unknown. The chemical and biological stability of blends should be investigated to ensure they meet the quality requirements for aviation fuels. This work aimed at evaluating the behavior of two fungi Hormoconis resinae (F089) and Exophiala phaeomuriformis (UFRGS Q4.2) in jet fuel, farnesane, and in 10% farnesane blend during simulated storage. Microcosms (150-mL flasks) were assembled with and without fungi containing Bushnell & Haas mineral medium for 28 days at a temperature of 20±2°C. The fungal growth (biomass), pH, surface tension, and changes in the fuel's hydrocarbon chains were evaluated. This study revealed thatthe treatment containing H. resinae showed a biomass of 19 mg, 12 mg, and 2 mg for jet fuel, blend, and farnesane respectively. The pH was reduced from 7.2 to 4.3 observed in jet fuel treatment The degradation results showed that compounds with carbon chains between C 9 and C 11 , in jet fuel, and blend treatments were preferably degraded. The highest biomass (70.9 mg) produced by E. phaeomuriformis was in 10% farnesane blend, after 21 days. However, no significant decrease was observed on pH and surface tension measurements across the treatments as well as on the hydrocarbons when compared to the controls. This study revealed that farnesane neither inhibited nor promoted greater growth on both microorganisms., (© 2023. The Author(s) under exclusive licence to Sociedade Brasileira de Microbiologia.)

In the search for microalgae species with potential for biodiesel production, Choricystis minor var. minor has been seen as a promising source of biomass due to its high lipid content and the satisfactory characteristics of its fatty acid methyl esters (FAMEs). For this reason, the objective of this study was to investigate the synergistic effect of growth conditions and organic carbon sources on cultivation of this microalga. To do so, experimental cultivations were conducted in photoautotrophic, heterotrophic and mixotrophic metabolisms using glucose, fructose, glycerol or sucrose - in growth conditions that use organic carbon. Thus, growth parameters of the cultures were evaluated and at the end of the cultivations, FAMEs yield and profile were determined by gas chromatography, the efficiency of carbon conversion into biomass was evaluated and a microbial analysis was conducted. Regarding growth conditions, the findings have confirmed that, regardless of the organic carbon source used, the heterotrophic and mixotrophic metabolisms can present advantages over the photoautotrophic one. In addition, biomass production was higher with the use of glucose than with other organic carbon sources, regardless of growth condition (heterotrophic or mixotrophic). Moreover, cultivations with the addition of CO 2 have converted carbon into biomass less efficiently. On the other hand, photoautotrophic cultures presented the lowest bacterial load. In comparison to photoautotrophic and mixotrophic, heterotrophic cultures have led to lower FAMEs content and higher yields of unsaturated fatty acids. The most satisfactory FAMEs profile for biodiesel production was obtained with mixotrophic growth using fructose., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

An innovative volatolomic approach employs the detection of biomarkers present in cerumen (earwax) to identify cattle intoxication by Stryphnodendron rotundifolium Mart., Fabaceae (popularly known as barbatimão). S. rotundifolium is a poisonous plant with the toxic compound undefined and widely distributed throughout the Brazilian territory. Cerumen samples from cattle of two local Brazilian breeds ('Curraleiro Pé-Duro' and 'Pantaneiro') were collected during an experimental intoxication protocol and analyzed using headspace (HS)/GC-MS followed by multivariate analysis (genetic algorithm for a partial least squares, cluster analysis, and classification and regression trees). A total of 106 volatile organic metabolites were identified in the cerumen samples of bovines. The intoxication by S. rotundifolium influenced the cerumen volatolomic profile of the bovines throughout the intoxication protocol. In this way, it was possible to detect biomarkers for cattle intoxication. Among the biomarkers, 2-octyldecanol and 9-tetradecen-1-ol were able to discriminate all samples between intoxicated and nonintoxicated bovines. The cattle intoxication diagnosis by S. rotundifolium was accomplished by applying the cerumen analysis using HS/GC-MS, in an easy, accurate, and noninvasive way. Thus, the proposed bioanalytical chromatography protocol is a useful tool in veterinary applications to determine this kind of intoxication., (© 2020 John Wiley & Sons, Ltd.)

Global energy demand is increasing every day and most is still derived from non-renewable sources. Therefore, sustainable alternatives are sought to produce biofuels, such as biodiesel. Several studies have demonstrated the potential of microalgae and cyanobacteria to produce biodiesel and pigments. These pigments, such as lutein and astaxanthin, have a high commercial value and can economically support the production of biodiesel. However, few studies have explored the potential of cyanobacteria collected in thermal water. In these microorganisms, both biomass and metabolites production can be altered by the culture form. Thus, a cosmopolitan filamentous cyanobacterium (Geitlerinema amphibium) from thermal water was collected and isolated to evaluate its potential to produce fatty acids, biodiesel, and pigments in two culture media. G. amphibium was cultured in WC (Wright's Cryptophyte) and BBM (Bold's Basal Medium) media. Thermal stress (40 °C for 48 h) was applied to the medium, which generated higher productivity of the biomass in BBM. The cyanobacterium contained higher biodiesel content in the WC medium and higher pigment content in the BBM medium. Thermal stress increased the biodiesel content by 350%, but decreased pigment content. Two pigments with high commercial value (astaxanthin and lutein) were identified. G. amphibium produced up to 2.74 mg g -1 of astaxanthin and 5.49 mg g -1 of lutein, which is seven times more lutein than Marigold, currently the main raw material used commercially. Therefore, G. amphibium has the potential to produce biodiesel, astaxanthin, and lutein concomitantly.