Composição de fenólicos, flavonoides, antocianinas, determinação da atividade antioxidante e comparação de métodos extrativos da folha e da casca de Caryocar brasiliense / Composition of Phenolic, Flavonoids, Anthocyanins, Determination of Antioxidant Activity and Comparison of Extractive Methods of Leaf and Bark of Caryocar brasiliense

Introdução: Caryocar brasiliense é conhecida popularmente como Pequi ou Pequizeiro, sendo uma planta com propriedades medicinais para tratamento de doenças respiratórias, úlceras gástricas e dores musculares. Objetivo: comparar a extração de biocompostos por meio de dois métodos extrativos, agitação magnética e banho ultrassônico. Além disso, avaliar a atividade antioxidante, o teor de compostos fenólicos, flavonoides e antocianinas em extratos das folhas e da casca de Pequi (C. brasiliense), com vistas a agregar valor quanto às suas propriedades funcionais. Metodologia: o conteúdo de compostos fenólicos foi determinado pelo método de Folin-Ciocalteu, flavonoides e antocianinas pelo método de Lima e Melo. A atividade antioxidante foi medida pelo método 2,2-difenil-1-picrilhidrazil (DPPH). Resultados: o extrato das folhas de Pequi exibiu maior teor de fenólicos em relação à casca, independente do método de extração. O extrato das folhas obtido em banho ultrassônico apresentou forte atividade antioxidante com valor de 72,2%. Conclusão: os extratos de Pequi demonstraram um perfil fitoquímico promissor que deve ser investigado no futuro para aplicação farmacológica como adjuvante ou precursor na síntese de novos cosméticos ou medicamentos com propriedades antioxidante.

Introduction: Caryocar brasiliense is a medicinal plant used in the treatment of respiratory diseases, gastric ulcers and muscle pain. Objective: to compare the extraction of natural compounds using two extractive methods, magnetic stirring and ultrasonic bath. In addition, to evaluate the antioxidant activity, the content of phenolic compounds, flavonoids and anthocyanins in the leaves and bark of Pequi (C. brasiliense), with a view to adding value through its functional properties. Methodology: the phenolic content was determined by the Folin-Ciocalteu method, flavonoids and anthocyanins by the Lima and Melo method. Antioxidant activity was measured using the 2.2-diphenyl-1-picrilhhydrazyl (DPPH) method. Results: the extract of the Pequi leaves exhibited a higher phenolic content in relation to the bark for both extraction methods. The Pequi leaf in an ultrasonic bath showed strong antioxidant activity with a value of 72.2%. Conclusion: Pequi extracts demonstrated a promising phytochemical profile that should be investigated in the future for pharmacological application as an adjuvant or precursor in the synthesis of a new cosmetic or medicine with antioxidant function.

Computational prediction and characterisation of miRNAs and their pathway genes in human schistosomiasis caused by Schistosoma haematobium

BACKGROUND Key genes control the infectivity of the Schistosoma haematobium causing schistosomiasis. A method for understanding the regulation of these genes might help in developing new disease strategies to control schistosomiasis, such as the silencing mediated by microRNAs (miRNAs). The miRNAs have been studied in schistosome species and they play important roles in the post-transcriptional regulation of genes, and in parasite-host interactions. However, genome-wide identification and characterisation of novel miRNAs and their pathway genes and their gene expression have not been explored deeply in the genome and transcriptome of S. haematobium. OBJECTIVES Identify and characterise mature and precursor miRNAs and their pathway genes in the S. haematobium genome. METHODS Computational prediction and characterisation of miRNAs and genes involved in miRNA pathway from S. haematobium genome on SchistoDB. Conserved domain analysis was performed using PFAM and CDD databases. A robust algorithm was applied to identify mature miRNAs and their precursors. The characterisation of the precursor miRNAs was performed using RNAfold, RNAalifold and Perl scripts. FINDINGS We identified and characterised 14 putative proteins involved in miRNA pathway including ARGONAUTE and DICER in S. haematobium. Besides that, 149 mature miRNAs and 131 precursor miRNAs were identified in the genome including novel miRNAs. MAIN CONCLUSIONS miRNA pathway occurs in the S. haematobium, including endogenous miRNAs and miRNA pathway components, suggesting a role of this type of non-coding RNAs in gene regulation in the parasite. The results found in this work will open up a new avenue for studying miRNAs in the S. haematobium biology in helping to understand the mechanism of gene silencing in the human parasite Schistosome.

Genome-wide identification, characterisation and expression profiling of the ubiquitin-proteasome genes in Biomphalaria glabrata

BACKGROUND Biomphalaria glabrata is the major species used for the study of schistosomiasis-related parasite-host relationships, and understanding its gene regulation may aid in this endeavor. The ubiquitin-proteasome system (UPS) performs post-translational regulation in order to maintain cellular protein homeostasis and is related to several mechanisms, including immune responses. OBJECTIVE The aims of this work were to identify and characterise the putative genes and proteins involved in UPS using bioinformatic tools and also their expression on different tissues of B. glabrata. METHODS The putative genes and proteins of UPS in B. glabrata were predicted using BLASTp and as queries reference proteins from model organism. We characterised these putative proteins using PFAM and CDD software describing the conserved domains and active sites. The phylogenetic analysis was performed using ClustalX2 and MEGA5.2. Expression evaluation was performed from 12 snail tissues using RPKM. FINDINGS 119 sequences involved in the UPS in B. glabrata were identified, which 86 have been related to the ubiquitination pathway and 33 to proteasome. In addition, the conserved domains found were associated with the ubiquitin family, UQ_con, HECT, U-box and proteasome. The main active sites were lysine and cysteine residues. Lysines are responsible and the starting point for the formation of polyubiquitin chains, while the cysteine residues of the enzymes are responsible for binding to ubiquitin. The phylogenetic analysis showed an organised distribution between the organisms and the clades of the sequences, corresponding to the tree of life of the animals, for all groups of sequences analysed. The ubiquitin sequence was the only one with a high expression profile found in all libraries, inferring its wide range of performance. MAIN CONCLUSIONS Our results show the presence, conservation and expression profile of the UPS in this mollusk, providing a basis and new knowledge for other studies involving this system. Due to the importance of the UPS and B. glabrata, this work may influence the search for new methodologies for the control of schistosomiasis.