Direct sulfur-containing compound speciation in crude oils and high-boiling fractions by APCI (+) FT-ICR mass spectrometry.

In this study, we focus on advancing the methodology for detecting sulfur-containing compounds (SCCs) in crude oils and their derivatives. These compounds are critical for geochemical analysis, crude oil evaluation, and overcoming production and refining challenges. Although various analytical techniques exist, the precision and resolution power of Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FT-ICR MS) stand out. However, the current methods for characterizing SCCs in petroleum products often lack standardization and tend to be complex and time-consuming. Our research introduces the use of Atmospheric Pressure Chemical Ionization (APCI) as an efficient alternative. We employed a mixture of toluene and methanol (1 : 1 ratio) for APCI, which demonstrated superior performance in sulfur speciation compared to mixtures of toluene and acetonitrile. Our specified method showed high repeatability, with coefficients of variation reported between 5% and 14%. This method effectively covers a wide range of double bond equivalents (DBEs) from 1 to 25 and various carbon numbers, demonstrating notable repeatability and reproducibility. Compared to results from ESI post-S-methylation and Atmospheric Pressure Photoionization (APPI), APCI offers a more comprehensive analysis of sulfur compounds, presenting a broad spectrum of molecular formulae and extending across a vast range of carbon numbers and DBEs. Here, we demonstrate that APCI is a robust and efficient method for direct and extensive sulfur speciation in crude oil and its high-boiling fractions, marking a significant advancement over existing techniques. This methodological improvement opens new pathways for more accurate and efficient sulfur compound analysis in petroleum products.

Weathering impacts on petroleum biomarker, aromatic, and polar compounds in the spilled oil at the northeast coast of Brazil over time.

After the wide oil spill reached the northeast of Brazil, the resurgence of oil was recorded and to evaluate this oil in detail, two samples collected in the state of Pernambuco in 2019 and 2021 were submitted to multiple analytical techniques. For both, we have found similar saturated biomarkers and triaromatic steroid ratios, implying that they are from the same spilled source. The n-alkanes, isoprenoids, and cycloalkanes were almost completely degraded due to evaporation, photooxidation, and/or biodegradation processes. The preferential loss of less alkylated PAHs than the more alkylated ones suggests that biodegradation was the most active process. This hypothesis is reinforced by the formation of mono and dicarboxylic acids assessed by GC × GC-TOFMS and ESI(-) FT-ICR MS high-resolution techniques. Furthermore, based on the ESI(-) FT-ICR MS results, three new ratios were proposed to evaluate the progress of the biodegradation process over time: Ox>2/O, SOx/SO, and SOx/N.

Vernonia polyanthes Less. (Asteraceae Bercht. & Presl), a Natural Source of Bioactive Compounds with Antibiotic Effect against Multidrug-Resistant Staphylococcus aureus.

Vernonia polyanthes is a medicinal plant used to treat many disorders, including infectious diseases. This study investigated the chemical constituents and the antibacterial activity of V. polyanthes leaf rinse extract (Vp-LRE). The chemical characterization of Vp-LRE was established using ultra-high performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry (UHPLC/Q-TOF-MS), and glaucolide A was identified through 1H and 13C nuclear magnetic resonance (NMR) and mass fragmentation. The cytotoxicity was evaluated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT). The antibacterial activity was assessed by minimal inhibitory concentration and minimal bactericidal concentration. Interactions between ligands and beta-lactamase were evaluated via molecular docking. UHPLC/Q-TOF-MS detected acacetin, apigenin, chrysoeriol, isorhamnetin, isorhamnetin isomer, kaempferide, 3',4'-dimethoxyluteolin, 3,7-dimethoxy-5,3',4'-trihydroxyflavone, piptocarphin A and glaucolide A. Vp-LRE (30 µg/mL) and glaucolide A (10 and 20 µg/mL) were cytotoxic against RAW 264.7 cells. Glaucolide A was not active, but Vp-LRE inhibited the Staphylococcus aureus, methicillin-resistant S. aureus (MRSA), Escherichia coli, Salmonella Choleraesuis and Typhimurium, with a bacteriostatic effect. The compounds (glaucolide A, 3',4'-dimethoxyluteolin, acacetin and apigenin) were able to interact with beta-lactamase, mainly through hydrogen bonding, with free energy between -6.2 to -7.5 kcal/mol. These results indicate that V. polyanthes is a potential natural source of phytochemicals with a significant antibiotic effect against MRSA strains.

Anti-Candida albicans Activity of Ononin and Other Secondary Metabolites from Platonia Insignis MART.

Candida albicans is a human pathogen that is part of the healthy microbiome. However, it is often associated with opportunistic fungal infections. The treatment of these infections is challenging because prolonged exposure to antifungal drugs can culminate in fungal resistance during therapy, and there is a limited number of available drugs. Therefore, this study investigated the antifungal activity of ononin by in silico and in vitro assays, and in Tenebrio molitor as an alternative in vivo model of infection caused by C. albicans. Ononin is an isoflavone glycoside derived from formononetin that has various biological activities. According in silico evaluation, ononin showed the best electron affinity in molecular docking with CaCYP51, with a binding free energy of -10.89 kcal/mol, superior to that of the antifungal drugs fluconazole and posaconazole. The ononin + CaCYP51 complex formed hydrogen bonds with Tyr132, Ser378, Phe380, and Met508, as well as hydrophobic connections with Tyr118, Leu121, Phe126, Leu131, Ile304, and Leu309, and interactions with the heme group. Ononin exerted anti-Candida albicans activity, with MIC between 3.9 and 7.8 µg/mL, and inhibited young and mature biofilms, with a reduction in cell density and metabolic activity of 50 to 80%. The compound was not cytotoxic to sheep red blood cells at concentrations up to 1000 µg/mL. Larvae of the mealworm T. molitor were used as an alternative in vivo model of C. albicans infection. Ononin was able to prolong larval survival at concentrations of 0.5, 1, and 5 mg/kg, and was not toxic up to a concentration of 20 mg/kg. Moreover, ononin reduced the fungal charge in treated animals. In conclusion, our results suggest that ononin has anti-Candida albicans activity and is a potential candidate for the development of new therapeutic alternatives.

Implications of microbial enhanced oil recovery and waterflooding for geochemical interpretation of recovered oils.

Biosurfactants and waterflooding have been widely reported thus far for enhancing oil production. Nevertheless, there is a lack of literature to explore enhanced oil recovered methods effects on its chemical composition. The aim of this work is to investigate the effects of a biosurfactant produced by Bacillus safensis and brine injection on the recovered petroleum composition, and their implications for geochemical interpretation. Original and oils recovered from displacement tests were analyzed by gas chromatography and ultra-high-resolution mass spectrometry, emphasizing saturated and aromatic biomarkers and basic and acidic polar compounds. Geochemical parameters based on some saturated compounds were subtly affected by the recovery methods, showing their reliable applicability in geochemical studies. Contrarily, parameters based on some aromatic compounds were more affected by biosurfactant flooding, mostly the low molecular weight compounds. Thus, these aromatic parameters should be applied with caution after such methods. The distribution of basic and acidic polar compounds can also be modified affecting the geochemical interpretation. In the case of the basic ones, the biosurfactant greatly influenced the N class species with favorable loss of lower aromaticity compounds. In addition to water solubilization, the compositional changes described in this study can be related to fractionation due to adsorption on reservoir rocks.

HIGH PREVALENCE OF NON-ADHERENCE TO ULCERATIVE COLITIS THERAPY IN REMISSION: KNOWING THE PROBLEM TO PREVENT LOSS.

BACKGROUND: Ulcerative colitis (UC) is a chronic inflammatory disease whose manifestations can drastically affect the individual's quality of life, and therefore adherence to treatment is important in order to keep it in remission. OBJECTIVE: To verify the prevalence of non-adherence and the influence of sociodemographic, clinical and pharmacotherapeutic characteristics associated with non-adherence to treatment of UC in remission. METHODS: Cross-sectional study conducted with 90 individuals diagnosed with UC in remission. The information was collected through interviews during medical consultations at Medical Clinic of Gastroenterology of Hospital Universitário da Universidade Federal de Juiz de Fora. To verify the association of the variables under study with the outcome of interest and its measure of association, Student's t-test or Pearson's chi-square non-parametric test (P<0.05) was used and prevalence ratio and confidence interval were calculated. RESULTS: A high prevalence of non-adherence (77.8%) was found among patients with UC in remission. The individuals most likely to not adhere to the treatment were those aged less than 50 years, who were not engaged in paid work, with high scores for anxiety and who used more than one medication as part of the treatment of UC. CONCLUSION: These findings reinforce that acknowledging the factors that influence the non-adherence behavior is of paramount importance for the development of strategies by health care professionals, assuring that those will be really effective to prolong, as much as possible, one of the most successful ways to maintain the UC remission period: the use of medications.

Elevada prevalência de não adesão ao tratamento da colite ulcerativa em remissão: conhecer o problema para prevenir o prejuízo / High prevalence of non-adherence to ulcerative colitis therapy in remission: knowing the problem to prevent loss

ABSTRACT Background Ulcerative colitis (UC) is a chronic inflammatory disease whose manifestations can drastically affect the individual's quality of life, and therefore adherence to treatment is important in order to keep it in remission. Objective To verify the prevalence of non-adherence and the influence of sociodemographic, clinical and pharmacotherapeutic characteristics associated with non-adherence to treatment of UC in remission. Methods Cross-sectional study conducted with 90 individuals diagnosed with UC in remission. The information was collected through interviews during medical consultations at Medical Clinic of Gastroenterology of Hospital Universitário da Universidade Federal de Juiz de Fora. To verify the association of the variables under study with the outcome of interest and its measure of association, Student's t-test or Pearson's chi-square non-parametric test (P<0.05) was used and prevalence ratio and confidence interval were calculated. Results A high prevalence of non-adherence (77.8%) was found among patients with UC in remission. The individuals most likely to not adhere to the treatment were those aged less than 50 years, who were not engaged in paid work, with high scores for anxiety and who used more than one medication as part of the treatment of UC. Conclusion These findings reinforce that acknowledging the factors that influence the non-adherence behavior is of paramount importance for the development of strategies by health care professionals, assuring that those will be really effective to prolong, as much as possible, one of the most successful ways to maintain the UC remission period: the use of medications.

RESUMO Contexto Colite ulcerativa é uma doença inflamatória crônica que pode apresentar manifestações graves que afetam drasticamente a qualidade de vida do indivíduo e, dessa maneira, a adesão ao tratamento é importante a fim de manter a doença em remissão. Objetivo Verificar a prevalência de não adesão e a influência de características sociodemográficas, clínicas e farmacoterapêuticas associadas a não adesão ao tratamento da colite ulcerativa em remissão. Métodos Estudo transversal envolvendo 90 indivíduos diagnosticados com colite ulcerativa em remissão. As entrevistas foram conduzidas durante as consultas médicas realizadas na Clínica Médica de Gastroenterologia do Hospital Universitário da Universidade Federal de Juiz de Fora. Para verificar a associação entre as variáveis com o desfecho de interesse, foi aplicado teste-t de Student ou teste não-paramétrico qui-quadrado de Pearson (P<0,05) e também razão de prevelência e intervalos de confiança foram calculados. Resultados Uma elevada prevalência de não adesão (77,8%) foi encontrada dentre os pacientes com colite ulcerativa em remissão. Os indivíduos mais propensos ao comportamento em questão foram aqueles com menos de 50 anos, sem trabalho remumerado, com escores mais elevados no teste de ansiedade e que utilizavam mais de um medicamento para o tratamento da colite ulcerativa. Conclusão Estes achados reforçam que o conhecimento de fatores que influenciam o comportamento de não adesão é de grande importância para o desenvolvimento de estratégias para a equipe de saúde, garantindo que estas sejam realmente eficazes para prolongar, tanto quanto possível, uma das formas mais bem-sucedidas de manter o período de remissão da colite ulcerativa: o uso de medicamentos.

Potential use of distinct biomarkers (trace metals, micronuclei, and nuclear abnormalities) in a heterogeneous sample of birds in southern Brazil.

The analysis of metal concentrations in bird feathers and genotoxicity tests are tools used to evaluate anthropogenic impacts on ecosystems. We investigated the response of birds, used as bioindicators, to disturbances observed in three areas with distinctive environmental characteristics (natural, agricultural, and urban) in southern Brazil. For this purpose, we quantified metals (Mn, Cu, Cr, and Zn) in feathers and determined the number of micronuclei (MN) and other nuclear abnormalities (NA) in 108 birds from 25 species and 17 families captured in the study area. No significant differences was found in the metal concentrations and the number of MN and NA between the sampling areas. Zn and Cu concentrations were significantly higher in insectivorous than those in omnivorous birds. The Zn concentration was significantly different between some species, and the Cu concentration was significantly higher in juveniles than that in adults. The best generalized linear models showed that omnivorous birds had more MN and NA and that juveniles and birds with better body condition index had increased NA numbers. This study demonstrates that the analyzed variables contribute in different ways to the result of each biomarker, mainly due to particular ecological and physiological characteristics of each species. We conclude that wild birds have the potential to be used as environmental bioindicators in the study area, but future studies should focus on one or a few species whose ecological and physiological habits are well known.

In vitro and in vivo anti-inflammatory properties of imine resveratrol analogues.

Resveratrol is a natural polyphenol found mainly on red grapes and in red wine, pointed as an important anti-inflammatory/immunomodulatory molecule. However, its bioavailability problems have limited its use encouraging the search for new alternatives agents. Thus, in this study, we synthetize 12 resveratrol analogues (6 imines, 1 thioimine and 5 hydrazones) and investigated its cytotoxicity, antioxidant activity and in vitro anti-inflammatory/immunomodulatory properties. The most promising compounds were also evaluated in vivo. The results showed that imines presented less cytotoxicity, were more effective than resveratrol on DPPH scavenger and exhibited an anti-inflammatory profile. Among them, the imines with a radical in the para position, on the ring B, not engaged in an intramolecular hydrogen-interaction, showed more prominent anti-inflammatory activity modulating, in vivo, the edema formation, the inflammatory infiltration and cytokine levels. An immunomodulatory activity also was observed in these molecules. Thus, our results suggest that imines with these characteristics presents potential to control inflammatory disorders.

Chemical composition and antifungal activity of essential oil from Eucalyptus smithii against dermatophytes.

INTRODUCTION: In this study, we evaluated the chemical composition of a commercial sample of essential oil from Eucalyptus smithii R.T. Baker and its antifungal activity against Microsporum canis ATCC 32903, Microsporum gypseum ATCC 14683, Trichophyton mentagrophytes ATCC 9533, T. mentagrophytes ATCC 11480, T. mentagrophytes ATCC 11481, and Trichophyton rubrum CCT 5507. METHODS: Morphological changes in these fungi after treatment with the oil were determined by scanning electron microscopy (SEM). The antifungal activity of the oil was determined on the basis of minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) values. RESULTS: The compound 1,8-cineole was found to be the predominant component (72.2%) of the essential oil. The MIC values of the oil ranged from 62.5µg·mL-1 to >1,000µg·mL-1, and the MFC values of the oil ranged from 125µg·mL-1 to >1,000µg·mL-1. SEM analysis showed physical damage and morphological alterations in the fungi exposed to this oil. CONCLUSIONS: We demonstrated the potential of Eucalyptus smithii essential oil as a natural therapeutic agent for the treatment of dermatophytosis.

Chemical composition and antifungal activity of essential oil from Eucalyptus smithii against dermatophytes

ABSTRACT INTRODUCTION: In this study, we evaluated the chemical composition of a commercial sample of essential oil from Eucalyptus smithii R.T. Baker and its antifungal activity against Microsporum canis ATCC 32903, Microsporum gypseum ATCC 14683, Trichophyton mentagrophytes ATCC 9533, T. mentagrophytes ATCC 11480, T. mentagrophytes ATCC 11481, and Trichophyton rubrum CCT 5507. METHODS: Morphological changes in these fungi after treatment with the oil were determined by scanning electron microscopy (SEM). The antifungal activity of the oil was determined on the basis of minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) values. RESULTS: The compound 1,8-cineole was found to be the predominant component (72.2%) of the essential oil. The MIC values of the oil ranged from 62.5μg·mL−1 to >1,000μg·mL−1, and the MFC values of the oil ranged from 125μg·mL−1 to >1,000μg·mL−1. SEM analysis showed physical damage and morphological alterations in the fungi exposed to this oil. CONCLUSIONS: We demonstrated the potential of Eucalyptus smithii essential oil as a natural therapeutic agent for the treatment of dermatophytosis.

Antifungal activity of Copaifera langsdorffii Desf oleoresin against dermatophytes.

Dermatophytoses are mycoses that affect keratinized tissues in both humans and animals. The aim of this study was to investigate the antifungal activity of the oleoresin extracted from Copaifera langsdorffii Desf. against the strains Microsporum canis ATCC 32903, Microsporum gypseum ATCC 14683, Trichophyton mentagrophytes ATCC 11481 and Trichophyton rubrum CCT 5507. The antimicrobial activity was determined by minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) values. Ketoconazole and terbinafine were used as reference drugs. The copaiba oleoresin showed moderate fungicidal activity against T. mentagrophytes ATCC 11481 (MIC and MFC = 170 µg mL-1) and weak fungicidal activity against T. rubrum CCT 5507 (MIC = 1,360 µg mL-1 and MFC = 2,720 µg mL-1). There was no activity against M. canis ATCC 32903 and M. gypseum ATCC 14683. SEM analysis revealed physical damage and morphological alterations such as compression and hyphae clustering in the structure of the fungi exposed to the action of the oleoresin. The results stimulate the achievement of in vivo assays to confirm the benefits of the application of oleoresin extracted from copaiba in the treatment of dermatophytosis, both in humans and in animals.

Inhibitory effects of resveratrol analogs on mushroom tyrosinase activity.

Skin pigmentation disorders typically involve an overproduction or uneven distribution of melanin, which results in skin spots. Resveratrol can inhibit tyrosinase, the active enzyme in the synthesis of melanin, but it does not inhibit the synthesis of melanin to an extent that enables its use alone as a skin whitening agent in pharmaceutical formulations, so its use as a coadjuvant in treatment of hyperpigmentation is suggested. Six resveratrol analogs were tested for tyrosinase inhibitory activity in vitro. Among the analogs tested, compound D was the most powerful tyrosinase inhibitor (IC(50) = 28.66 µg/mL), two times more active than resveratrol (IC(50) = 57.05 µg/mL), followed by the analogs A, E, B, F and C, respectively. This demonstrated that the hydroxylation at C4' on the phenolic ring was the molecular modification with most importance for the observed activity.

Antiproliferative activity of Luehea candicans Mart. et Zucc. (Tiliaceae).

Luehea candicans Mart. et Zucc. (Tiliaceae) is known as 'açoita-cavalo' and is one of the most important medicinal plants found in the Brazilian cerrado. The crude methanolic extracts of the branches and leaves and their fractions were evaluated using the following cancer cell lines: MCF-7 (breast), NCI-ADR (breast expressing the multidrug resistance phenotype), NCI-460 (lung), UACC-62 (melanoma), 786-0 (kidney), OVCAR (ovarian), PCO-3 (prostate), HT-29 (colon) and K-562 (leukaemia). The crude methanolic extracts from the branches (B) and leaves (L) were able to inhibit the growth of the K-562 and 786-0 cell lines in a dose-dependent manner, with GI(50) values of 8.1 and 5.4 µg mL(-1), respectively. The hexane (L1), chloroform (L2) and methanol (L4) fractions derived from extract L showed a high selectivity and pronounced cytostatic activity against 786-0 (GI(50) ~ 40 µg mL(-1)). A significant amount of lupeol was isolated from fraction L2. The chloroform (B2) and methanol (B3) fractions derived from extract (B) exhibited less selectivity, showing the highest cytostatic activity against K-562, NCI-ADR, OVCAR, MCF-7 and NCI-460 cells, with GI(50) values between 27 and 40 µg mL(-1). Lupeol, betulin, a mixture of steroids, (-)-epicatechin, vitexin and liriodendrin were isolated from these active fractions.