A veterinary cerumenomic assay for bovine laminitis identification

Bovine laminitis disorder results in animal welfare and economic concerns in dairy and beef farms worldwide. However, the affected metabolic pathways, pathophysiologic characteristics, and inflammatory mechanisms remain unclear, hampering the development of new diagnostics. Using cerumen (earwax) as a source of volatile metabolites (cerumenomic) that carry valuable biological information has interesting implications for veterinary medicine. Nonetheless, up to now, no applications of veterinary cerumenomic assays have been made to identify bovine laminitis. This work aims to develop a veterinary cerumenomic assay for bovine laminitis identification that is non-invasive, robust, accurate, and sensitive to detecting the metabolic disturbances in bovine volatile metabolome. Twenty earwax samples (10 from healthy/control calves and 10 from laminitis calves) were collected from Nellore cattle, followed by Headspace/Gas Chromatography-Mass Spectrometry (HS/GC-MS) analysis and biomarker selection in two multivariate approaches: semiquantitative (intensity data) and semiqualitative (binary data). Following the analysis, cerumen volatile metabolites were indicated as candidate biomarkers for identifying bovine laminitis by monitoring their intensity or occurrence. In the semiquantitative strategy, the p-cresol presented the highest diagnostic figures of merit (area under the curve: 0.845, sensitivity: 0.700, and specificity: 0.900). Regarding the binary approach, a panel combining eight variables/volatiles, with formamide being the most prominent one, showed an area under the curve, sensitivity, and specificity of 0.97, 0.81, and 0.90, respectively. In summary, this work describes the first veterinary cerumenomic assay for bovine laminitis that indicates new metabolites altered during the inflammatory condition, paving the way for developing laminitis early diagnosis by monitoring the cerumen metabolites.

Preliminary assessment of toxicity of aerosol samples from central-west Brazil using Artemia spp. bioassays

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.

A cerumenolomic approach to bovine trypanosomosis diagnosis

INTRODUCTION

Trypanosomiasis caused by Trypanosoma vivax (T. vivax, subgenus Duttonella) is a burden disease in bovines that induces losses of billions of dollars in livestock activity worldwide. To control the disease, the first step is identifying the infected animals at early stages. However, convention tools for animal infection detection by T. vivax present some challenges, facilitating the spread of the pathogenesis.

OBJECTIVES

This work aims to develop a new procedure to identify infected bovines by T. vivax using cerumen (earwax) in a volatilomic approach, here named cerumenolomic, which is performed in an easy, quick, accurate, and non-invasive manner.

METHODS

Seventy-eight earwax samples from Brazilian Curraleiro Pé-Duro calves were collected in a longitudinal study protocol during health and inoculated stages. The samples were analyzed using Headspace/Gas Chromatography-Mass Spectrometry followed by multivariate analysis approaches.

RESULTS

The cerumen analyses lead to the identification of a broad spectrum of volatile organic metabolites (VOMs), of which 20 VOMs can discriminate between healthy and infected calves (AUC = 0.991, sensitivity = 0.967, specificity = 1.000). Furthermore, 13 VOMs can indicate a pattern of discrimination between the acute and chronic phases of the T. vivax infection in the animals (AUC = 0.989, sensitivity = 0.944, specificity = 1.000).

CONCLUSION

The cerumen volatile metabolites present alterations in their occurrence during the T.vivax infection, which may lead to identifying the infection in the first weeks of inoculation and discriminating between the acute and chronic phases of the illness. These results may be a breakthrough to avoid the T. vivax outbreak and provide a faster clinical approach to the animal.

Vinegar from Anacardium othonianum Rizzini using submerged fermentation

BACKGROUND

Anacardium othonianum Rizzini is a native Cerrado fruit, recently described in the literature. Its use is restricted to its native region and there is a lack of studies regarding production of vinegar from the pulp. This work aims to investigate the production of A. othonianum Rizzini vinegar using submerged fermentation.

RESULTS

The density, alcohol content, proximal composition, pH, color coordinates, and chromatographic profile of the volatile compounds were analyzed in the slurry, fermented juice, and vinegar produced from the corpulent parts of A. othonianum Rizz. Sensory acceptance and willingness to pay were also assessed with vinegar at 4% and 6% of total acidity. The results indicated compliance with European legislation and the presence of volatile compounds such as carbon dioxide, acetic acid, ethanol, and acetaldehyde in the analyzed vinegars. Our results indicate the potential of vinegar production from A. othonianum, with 74% and 86% willingness to pay.

CONCLUSIONS

The process of transformation of the fruit pulp into new products can contribute to fruit valorization and consequent preservation of the plant in the Cerrado biome. To the best of our knowledge, this is the first report of volatile compounds and minerals in A. othonianum Rizz. slurry. Our observations can be used as a basis for future studies regarding the preparation of vinegars from this species and for investigating their application in cooking and guiding consumer perception. © 2020 Society of Chemical Industry.

Synergistic effect of growth conditions and organic carbon sources for improving biomass production and biodiesel quality by the microalga Choricystis minor var. minor

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 CO₂ 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.

A volatolomic approach using cerumen as biofluid to diagnose bovine intoxication by Stryphnodendron rotundifolium

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.

Direct Dielectric Barrier Discharge Ionization Promotes Rapid and Simple Lubricant Oil Fingerprinting

Petroleomics, which is the characterization, separation, and quantification of the components of petroleum and crude oil, is an emerging area of study. However, the repertoire of analytical methods available to understand commercial automotive lubricant oils (ALOs) is very limited. Ambient mass spectrometry is one of the most sensitive analytical methods for real-time and in situ chemical analysis. With this technique, the chemical fingerprinting of ALOs can be performed quickly and simply using dielectric barrier discharge ionization time-of-flight mass spectrometry. In this study, the mass spectra of 35 samples were obtained without any sample preparation in positive-ion mode, and no carryover was observed. To elucidate the similarities and differences between the ALO samples, the data generated from these spectra were analyzed using four chemometric techniques: principal component analysis, multivariate curve resolution, hierarchical cluster analysis, and pattern recognition entropy. The ALO samples were readily differentiated according to their American Petroleum Institute classification and base oil types: mineral, semisynthetic, and synthetic. The development of this new methodology will aid in the semiquantitative control analysis of ALOs and offers an improved ability to identify the components therein.

Development of Methods to Quantify Free and Conjugated Steroids in Fatty Matrices by HPLC-MS/MS

Steroids are called the "fingerprint" of oils, fats, and their derivatives. Different classes of steroids may be present in these matrices. Most of the methods developed to analyze these constituents involve the determination of free steroid content, although their conjugated forms are extremely important in determining the total composition. Thus, this article demonstrates that the coupling of sequential mass spectrometry and high-performance liquid chromatography obtained high sensitivity and high specificity of mass resolution to identify and quantify the main classes of steroids. Four methods were developed to quantify steroids free, esterified, glucosides, and acylated glucosides by internal standardization using betulin. The main validation parameters were tested and demonstrated good correlation results for the methods. The content of free steroids was the majority in all samples, whereas the content of glucoside steroids was the least abundant. The contents of free steroids quantified in the degummed soybean oil were significantly reduced in relation to the refined oil. A small amount of esterified steroids was superior in refined soybean oil than in degummed oil. Comparing the steroid content between degummed oil and biodiesel, we found that the concentration of free and esterified steroids decreases in the conversion to biodiesel, whereas the concentration of glucoside steroids increases slightly.

Removal of BTEX from aqueous solution using Moringa oleifera seed cake

In this study, the removal of BTEX (benzene, toluene, ethylbenzene, p-xylene and o-xylene) from aqueous solution using Moringa oleifera seed cake (MOSC) was investigated. The effect of parameters such as contact time, pH and initial BTEX concentration were studied to optimize the conditions for maximum removal. Maximum removal values of 75 +/- 1%, 85 +/- 2%, 86 +/- 2%, 88 +/- 2% and 87 +/- 1% were obtained for benzene, toluene, ethylbenzene, p-xylene and o-xylene, respectively, at pH 7.0, with a 20 min contact time for an adsorbent dose of 10 g L(-1) of 1 mg L(-1) BTEX concentration. The adsorption data fitted the Langmuir and Freundlich adsorption isotherms. The capacity of MOSC to adsorb BTEX was compared with that for a commercial activated carbon. The results from the two methods were not significantly different (judged by t-test at 95% confident interval). A low cost, easy purchase and the satisfactory experimental results indicated that MOSC is a promising natural material for the removal of BTEX from aqueous solution.