Comparison of generational effect on proteins and metabolites in non-transgenic and transgenic soybean seeds through the insertion of the cp4-EPSPS gene assessed by omics-based platforms.

This work evaluates different generations of transgenic (cp4-EPSPS gene) and non-transgenic soybean plants through proteomics and metabolomics. For proteomics purpose, 24 differentially abundant protein spots were found through 2-D DIGE, being 4 belonging to transgenic plants. From this total, 19 were successfully identified, storage proteins as predominant class. Some identified proteins are involved in growing and cell division, and stress response, such as LEA and dehydrin. For metabolomics, 17 compounds were putatively annotated, mainly belonging to the secondary metabolism, such as flavonoids. From these analyzes, all generations and varieties of the soybean are prone to be differentiate by PLS-DA. According to our results, transgenic plants appear to be more stable than non-transgenic ones. In addition, the omics-based approaches allowed access some relations between those differential spot proteins and metabolites, mainly those storage proteins and flavonoid.

Pigments in an iridescent bacterium, Cellulophaga fucicola, isolated from Antarctica.

An iridescent yellow pigmented bacterium isolated from the Antarctic continent, named Cellulophaga fucicola strain 416, was found to be able to tolerate UV-B radiation. Its crude pigment extract was tested for antioxidant capacity, UV light stability and phototoxicity profile against murine fibroblast lines. The pigments were further isolated and chemically identified by ultra-high-performance liquid chromatography with photodiode array and mass spectrometry detectors. The results showed that the pigment extract presented weak stability under exposure to UV light, a phototoxic profile in the 3t3 Neutral Red Uptake test and a very high antioxidant activity, suggesting that it could be used as food and feed colourants. Zeaxanthin and two isomers of zeaxanthin, ß-cryptoxanthin and ß-carotene, were identified using a C18 column. These five carotenoids were the major pigments isolated from C. fucicola 416. In conclusion, the identification of pigments produced by the bacterial strain under study may help us understand how bacteria thrive in high UV and cold environments, and opens avenues for further biotechnological application towards a more sustainable and environmentally friendly way of pigment exploitation.

Lipid and protein fingerprinting for Fusarium oxysporum f. sp. cubense strain-level classification.

Banana is one of the most popular fruits in the world but has been substantially impaired by Panama disease in the last years. Fusarium oxysporum f. sp. cubense (Foc) is the causal agent and colonizes banana cultivars from many subgroups with different aggressiveness levels, often leading to plant death while compromising new crops in infested areas. This study has evaluated the ability of MALDI-MS protein and lipid fingerprinting to provide intraspecies classification of Foc isolates and to screen biomolecules related to host-pathogen relationship. The MS data, when inspected via partial least square discriminant analysis (PLS-DA), distinguished the isolates by aggressiveness as well as by specific location and host. Although both lipids and proteins show discriminating tendencies, these differences were more clearly perceived via the protein profiles. Considering that Cavendish cultivar is the more resistant option to endure Foc presence in the field, the lipids and proteins related to this subgroup might have an important role in pathogen adaptation. This study reports a new application of MALDI-MS for the analysis of a banana pathogen with intraspecies classification ability. Graphical abstract MALDI-MS classified Foc isolates by aggressiveness level on banana revealing the additional influence of location and host cultivar on the expression of lipids and proteins.

The occurrence of pristine and functionalized fullerenes as constituents of airborne aerosols.

We investigated if pristine and functionalized fullerenes could be actual constituents of fine atmospheric aerosols. Comprehensive profiles of fullerenes from 1 µL extracts were made through matrix laser desorption ionization Time-of-Flight Mass Spectrometry (MALDI-MS) within a few minutes. The ion with m/z 720, corresponding to [C60]-•, was identified as fullerene after 1 µL of α-cyano-4-hydroxycinnamic acid matrix solution was spotted over the dried extracts. The ions with the m/z corresponding to C70, C76, C84, C100, C118, C128, and C130 were also attributed to other fullerene species detected within the samples. The ion m/z 878 was found to be the fullerene derivative diethyl methano[60]fullerene dicarboxylate. Since ions of fragmented fullerene molecules were not detected even at high laser energies, we considered the fullerenes' occurring as original constituents of real atmospheric particle matrices instead of being formed as artifacts of the laser action on samples. Therefore, this protocol would be helpful in the understanding of the distribution of either pristine or functionalized fullerenes in the environment and their participation in atmospheric chemistry under typical conditions, as well as its application in vitro and in vivo (eco)toxicity studies.

Multi-residue analysis of pesticide residues in mangoes using solid-phase microextraction coupled to liquid chromatography and UV-Vis detection.

A sensitive and efficient solid-phase microextraction method, based on liquid chromatography and UV-Vis detection, was developed and validated as an alternative method for sample screening prior to LC-MS analysis. It enables the simultaneous determination of ten pesticides in mango fruits. The fiber used was polydimethylsiloxane while optimum SPME conditions employed have been developed and optimized in a previous work. The desorption process was performed in static mode, using acetonitrile as a solvent. The results indicate that the DI-SPME/HPLC/UV-Vis procedure resulted in good linear range, accuracy, precision and sensibility and is adequate for analyzing pesticide residues in mango fruits. The limits of detection (0.6-3.3 µg/kg) and quantification (2.0-10.0 µg/kg) were achieved with values lower than the maximum residue levels (MRLs) established by Brazilian legislation for all pesticides in this study. The average recovery rates obtained for each pesticide ranged from 71.6 to 104.3% at three fortification levels, with the relative standard deviation ranging from 4.3 to 18.6%. The proposed method was applied for the determination of the aforementioned compounds in commercial mango samples and residues of azoxystrobin, fenthion, permethrin, abamectin and bifenthrin were detected in the mango samples, although below the MRLs established by Brazilian legislation.

Comprehensive characterization of lipids from Amazonian vegetable oils by mass spectrometry techniques.

An integrative approach in mass spectrometry (MS) comprising gas chromatography coupled to MS (GC-MS), ultra-efficiency liquid chromatography coupled to MS (UPLC-MS) and easy ambient sonic-spray ionization MS (EASI-MS) is proposed for the comprehensive characterization of Amazonian oils. Coconut, andiroba and castor seed oils, which are vastly sold in markets of the Amazonian region of Brazil, were selected as a representative test set. These oils were found to contain several lipids such as triacylglycerides (TAGs), fatty acids (FAs), phytosterols and limonoids. In the analyzed samples 30 different TAGs, 11 FAs, 6 phytosterols and 7 limonoids were identified. The antioxidant capacity (AOC) of the oils, as measured by their oxygen radical absorbance capacity (ORAC), was also used to evaluate their potential biological properties as well as their possible consumption as food. Edible virgin coconut oil was the most active (0.720±0.001 Trolox eq./mmol), whereas considerable lower activity was observed for andiroba and castor seed oils. The antimicrobial activities of the oils were also recorded against a panel of pathogenic bacteria and fungi in which andiroba oil was the only one that was active, solely against Enterococcus aeruginosa.