Classification and Identification of Petroleum Microorganisms by MALDI-TOF Mass Spectrometry

<div><p>Indigenous bacteria isolated from a crude oil sample from a deep water reservoir in the Pampo Sul Oilfield (Campos Basin-RJ, Brazil) were previously classified as strains of B. pumilus. However, their enzymatic activities with fluorogenic probes and rates of petroleum biodegradation were completely different. Some of the bacteria depleted n-alkanes, whereas others did not. Aromatic compounds reported to be recalcitrant were also biodegraded by some of these Bacillus strains, revealing their outstanding ability to deplete petroleum. Further classification using matrixassisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF MS) followed by statistical analysis revealed that these strains could be clustered into three different groups, consistent with their enzymatic activity evaluation. A more accurate phylogenetic analysis using gyrB gene sequences confirmed the MALDI-TOF MS classification of three groups of strains and identified them as Bacillus safensis, B. cereus and B. thuringiensis.</p></div

A Prompt, Tough and Eco-Friendly (PTOCO) System for Mini-Scale Extraction of Samples for Antioxidant Capacity Assays

<div><p>The compound extraction is an important step before analyzing composition of samples with antioxidant capacity. Several extraction conditions can be employed (temperature, polarity of solvent and extraction time, for example), and the chosen variables exert great influence upon final results. Thus, in order to execute an efficient extraction, it is needed to manage them with rigor. In this work, a new device was designed and tested. The Prompt, TOugh and eCO-friendly (PTOCO) system is the first equipment in mini-scale that allows a good control of antioxidants extraction conditions. It is a simple and cheap device that only needs small amounts of sample and solvent to obtain sufficient volumes of extract for application in routine analytical methods. Twenty experiments from an experimental design were executed using only 0.5 g of oregano and 60 mL of water. The total antioxidant capacity assays, as well as the mass spectra, confirmed the extraction efficiency.</p></div

Stilbenes, phenanthrenes and antiproliferative activity of <i>Cattleya intermedia</i>

The phytochemical study of Cattleya intermedia (Orchidaceae) led to the isolation of two new stilbenoids and one new 9,10-dihydrophenanthrene, 4′,5-dihydroxy-2′,3-dimethoxy-dihydrostilbene (1), 3,6′-dihydroxy-4′-methoxy-dihydrostilbene (2) and 1,2,6-trihydroxy-3,8-dimethoxy-9,10-dihydrophenanthrene (3), named cattleymediol, cattleyol and phenanmediol, respectively, in addition to other five known compounds (4–8). The structural elucidations of the isolated compounds were carried out through the analyses of the one-dimensional 1H,1³C and NOE NMR spectra, and the 2D HSQC, HMBC, COSY and NOESY spectra, besides high-resolution mass spectrometry. In addition to this, the crude extract and its main fractions were analysed by ultra-high performance liquid chromatography coupled to high resolution mass spectrometry (UHPLC-QTOF-MS/MS), leading to the putative identification of several other compounds, including flavonoids and organic acids derivatives. Finally, the main fractions of the crude extract, and the pure compounds cattleymediol (1) and lusiantridine (7), had their antiproliferative activities evaluated against human cancerous HeLa and non-cancerous VERO cells.</p

CHEMICAL COMPOSITIONS AND ANTIOXIDANT AND ANTIMICROBIAL ACTIVITIES OF PROPOLIS PRODUCED BY Frieseomelitta longipes AND Apis mellifera BEES

<div><p>In this study, we investigated the chemical compositions and antioxidant and antimicrobial activities of propolis produced by the stingless bee Frieseomelitta longipes and the honeybee Apis mellifera collected from colonies in North Brazil. In terms of volatile composition, both mono- and sesquiterpenes were detected in the propolis of F. longipes while only sesquiterpenes were detected in that of A. mellifera. Out of 50 volatiles identified in all samples, 26 were found exclusively in F. longipes propolis and 8 were found exclusively in A. mellifera propolis. The chemical profiles of the propolis extracts were determined by atmospheric pressure chemical ionization-mass spectrometry and liquid chromatography-electrospray ionization-tandem mass spectrometry allowed to identify several prenylated benzophenones. A. mellifera extracts exhibited major antioxidant activity as assessed by the 2,2-diphenyl-1-picrylhydrazyl method and all extracts exhibited antioxidant activity as assessed by the β-carotene/linoleic acid method. The ethanolic extracts of the propolis showed promisor activity against all tested microorganisms.</p></div