Prospecção da rota de biossíntese de micrornas e avaliação antioxidante em diferentes variedades de lúpulo (Humulus lupulus l.)

Abstract

The present work was carried out with the objective of identifying the antioxidant potential of 3 bittering varieties (Galena, Sorachi Ace and Columbus Zeus) of hops (Humulus lupulus) and of 3 aroma varieties (East Kent Golding, Sladek and Cascade) by means of aqueous extracts made with the vegetable in a pelleted state, simulating the industrial process of adding hops during boiling, submitted to different evaluation methodologies. It was also aimed to identify and characterize, through in silico analysis, proteins of the MicroRNAs biosynthesis pathway, in addition to promoting the characterization of their primary and secondary structures. The extracts were obtained by boiling a system formed by 0.2g of pelleted plant material in 100mL of water. Boiling times were 60 minutes for bitter varieties and 5 minutes for aroma varieties. Statistical analyzes were performed using the Scott-Knott test at 5% probability in a completely randomized design. The DPPH (2,2-diphenyl-1-picrylhydrazyl) and ABTS (2,2-Azino-Bis(3-Ethylbenzothiazoline-6-Sulphonic Acid) Diamonic Acid) assays revealed a greater antioxidant potential of the East Kent, Galena and Cascade varieties. Columbus and Sladek did not receive top positions in most tests. The mass equivalence values in relation to the standard BHT (Butylhydroxytoluene) ranked the antioxidant potential of the varieties in the order East Kent, Galena, Cascade, Sorachi, Columbus and Sladek. The results suggested that the antioxidant activity is not dependent on the variety classification. It was possible to identify and characterize proteins of the hop microRNAs and microRNAs synthesis pathway by means of in silico analysis via Blast+, ClustalX2, MEGA and RNAalifold. 82 proteins were found, 17 belonging to Argonauts, 12 Dicers, 13 DRBs (Double-stranded RNA binding proteins) and 1 HEN1 (HUA ENHANCER 1 methyl-transferase enzyme). We identified 140 precursors of microRNAs and 192 mature ones that are part of 73 families. A high level of conservation of active sites in the proteins and in the primary and secondary structures of the predicted microRNAs compared to microRNA molecules and proteins from orthologous species was evidenced.