Development and validation of a LC-PDA method for methylphenidate analysis in sewage.

Methylphenidate (MPH) is an important emerging pollutant found in effluents and wastewater. Thus, we aimed to develop and validate a method for detection and quantitation of MPH residues in sewage through high performance liquid chromatography coupled with photodiode array detector (LC-PDA). Here we describe a selective, accurate, precise, and valid method for determination of MPH in sewage with a total running time of 10 min, with limits of detection and quantification of 0.27 and 0.92 µg/mL, respectively. MPH retention peak was observed at 5 min. The method was applied to MPH analysis in a sewage sample pretreated with solid phase extraction, obtaining a result of 2.8 µg/L of MPH. Thus, the developed method can be considered feasible to be applied to MPH residual contamination analysis in sewage using a widely available apparatus.

Cytotoxicity of different concentrations of glycolic acid and its effects on root dentin microhardness - An in vitro study.

The aim of the study was to evaluate the cytotoxicity of different glycolic acid concentrations (GA) and its effects on dentinal microhardness. Cytotoxicity was evaluated after inoculation of test irrigants in the lymphocyte primary culture for 3 min. The tested substances were distilled water(DW); 17% EDTA; QMix; 10% GA; 17% GA; and 25% GA. Counting of total, live and dead cells was performed, obtaining the average percentage of dead cells of each group. For microhardness evaluation, 60 root dentin samples were divided into the same tested groups (n = 10) and immersed in test irrigants for 3 min. Dentin microhardness was evaluated by Vicker test. Specific statistical analysis was made in both tests. Results showed significant lower cytotoxicity for QMix and 10% GA (P < 0.05). Moreover, all test irrigants presented similar values of microhardness than the control group (P > 0.05). In conclusion, lower GA concentration can be an alternative for final irrigation on endodontics.

Influence of Culturing Conditions on Bioprospecting and the Antimicrobial Potential of Endophytic Fungi from Schinus terebinthifolius.

In this study, we analyzed the antimicrobial activity of extracts harvested from 17 endophytic fungi isolated from the medicinal plant Schinus terebinthifolius. Morphological and molecular analyses indicated that these fungal species belonged to the genera Alternaria, Bjerkandera, Colletotrichum, Diaporthe, Penicillium, and Xylaria. Of the endophytes analyzed, 64.7 % produced antimicrobial compounds under at least one of the fermentation conditions tested. Nine isolates produced compounds that inhibited growth of Staphylococcus aureus, four produced compounds that inhibited Candida albicans, and two that inhibited Pseudomonas aeruginosa. The fermentation conditions of the following endophytes were optimized: Alternaria sp. Sect. Alternata-LGMF626, Xylaria sp.-LGMF673, and Bjerkandera sp.-LGMF713. Specifically, the carbon and nitrogen sources, initial pH, temperature, and length of incubation were varied. In general, production of antimicrobial compounds was greatest when galactose was used as a carbon source, and acidification of the growth medium enhanced the production of compounds that inhibited C. albicans. Upon large-scale fermentation, Alternaria sp. Sect. Alternata-LGMF626 produced an extract containing two fractions that were active against methicillin-resistant S. aureus. One of the extracts exhibited high activity (minimum inhibitory concentration of 18.52 µg/mL), and the other exhibited moderate activity (minimum inhibitory concentration of 55.55 µg/mL). The compounds E-2-hexyl-cinnamaldehyde and two compounds of the pyrrolopyrazine alkaloids class were identified in the active fractions by gas chromatography-mass spectrometry.

Phytochemical profile and antimicrobial properties of Lotus spp. (Fabaceae).

The phytochemical profile and antimicrobial activity of cultivar (cv.) extracts of Lotus uliginosus (cvs. Trojan and Serrano), L. tenuis (cv. Larrañaga) and L. corniculatus (cv. São Gabriel) were investigated. The phytochemical analysis revealed tannins, coumarins and flavonoids in all extracts, with variations among cultivars, showing genotypic variability. By High Performance Liquid Chromatographic method, the cvs. Larrañaga and São Gabriel showed the highest percentage of catechin and epicatechin, respectively, and presented rutin, which was not detected in the other ones. These genotypes showed antifungal activity but not antibacterial one. The cv. Larrañaga inhibited the mycelia growth of Alternaria sp. and Fusarium graminearum while the cv. São Gabriel was active only against Alternaria sp. The cultivars showed the greatest amounts of secondary metabolites and demonstrated significant activity against filamentous fungi. The results provide a direction for further research about pharmacological use of Lotus spp.

Avaliação da qualidade microbiológica de cápsulas e chás de plantas utilizadas na assistência ao tratamento da obesidade / Microbiological quality evaluation of herbal capsules and teas to assist the treatment of obesity

O uso de plantas diuréticas e laxativas é uma alternativa medicamentosa para muitas pessoas que objetivam o emagrecimento com menores efeitos adversos. A avaliação microbiológica é um requisito essencial para a garantia de qualidade dos produtos. A finalidade deste trabalho foi avaliar a qualidade microbiológica de cápsulas e chás de alcachofra (Cynara scolymus L.), centella asiática (Hydrocotile asiatica L.), fucus (Fucus vesiculosus L.), e sene (Cassia acutifolia Delile), através da contagem de micro-organismos viáveis totais e pesquisa de patógenos. Na contagem de micro-organismos viáveis, os chás analisados foram aprovados, pois apesar de apresentarem uma carga microbiana elevada, esta se encontrava dentro das especificações, entretanto, 16,66% e 66,66% das cápsulas analisadas foram reprovadas por apresentaram quantidades superiores de bactérias e fungos, respectivamente. Na pesquisa de patógenos, 76% das amostras (88% dos chás e 58% das cápsulas) apresentaram um ou mais de um tipo de micro-organismo. Salmonella sp. esteve presente em 33% das amostras evidenciando a qualidade microbiológica insatisfatória dos produtos encontrados no mercado. Estes resultados demonstram a necessidade da realização do controle de qualidade tanto das matérias-primas vegetais, quanto dos produtos acabados, através do controle e fiscalização rigorosa, com adoção de medidas regulamentadoras e educativas.

The use of laxative and diuretic herbal drugs is an alternative therapy for many people looking for loosing weight with fewer side effects. The microbiological evaluation is an essential requirement for the quality assurance of products. This study aimed to evaluate the microbial quality of artichoke (Cynara scolymus L.), centella (Hydrocotile asiatica L.), fucus (Fucus vesiculosus L.), and Senna (Cassia acutifolia Delile) capsules and teas, by counting the total viable aerobic microorganisms and through tests for specified microorganisms. On the total viable aerobic microorganisms count, the teas analyzed were approved, because although they had a high microbial load, this was in accordance with the specifications, however 16.66% and 66.66% of the capsules analyzed were rejected because they presented higher amounts of bacteria and fungi, respectively. In relation to the tests for specified microorganisms, 76% of the samples (88% of the teas and 58% of the capsules) presented one or more than one type of microorganisms. Salmonella sp. was present in 33% of the samples, showing the unsatisfactory microbial quality of the products in the market. These results demonstrate the necessity of performing quality control both on herbal raw material and finished products, through a rigorous control and inspection, adopting regulatory and educational measures.