Effects of Achyrocline satureioides Inflorescence Extracts against Pathogenic Intestinal Bacteria: Chemical Characterization, In Vitro Tests, and In Vivo Evaluation.

Karla Suzana Moresco,Alexandre Kleber Silveira,José Cláudio Fonseca Moreira,Fares Zeidán-Chuliá,Ana Paula Folmer Correa,Daniel Pens Gelain,Adriano Brandelli,Rafael R Oliveria,Valquiria Linck Bassani,Lucas Grun,Adriana Giongo Borges,Maria Goretti Rodrigues Vale,Florencia Barbé-Tuana,Ariane Zmozinski

doi:10.1155/2017/4874865

Abstract

Three Achyrocline satureioides (AS) inflorescences extracts were characterized: (i) a freeze-dried extract prepared from the aqueous extractive solution and (ii) a freeze-dried and (iii) a spray-dried extract prepared from hydroethanol extractive solution (80% ethanol). The chemical profile, antioxidant potential, and antimicrobial activity against intestinal pathogenic bacteria of AS extracts were evaluated. In vitro antioxidant activity was determined by the total reactive antioxidant potential (TRAP) assay. In vivo analysis and characterization of intestinal microbiota were performed in male Wistar rats (saline versus treated animals with AS dried extracts) by high-throughput sequencing analysis: metabarcoding. Antimicrobial activity was tested in vitro by the disc diffusion tests. Moisture content of the extracts ranged from 10 to 15% and 5.7 to 17 mg kg−1 of fluorine. AS exhibited antioxidant activity, especially in its freeze-dried form which also exhibited a wide spectrum of antimicrobial activity against intestinal pathogenic bacteria greater than those observed by the antibiotic, amoxicillin, when tested against Bacillus cereus and Staphylococcus aureus. Antioxidant and antimicrobial activities of AS extracts seemed to be positively correlated with the present amount of flavonoids. These findings suggest a potential use of AS as a coadjuvant agent for treating bacterial-induced intestinal diseases with high rates of antibiotic resistance.

Highlights

Many bacterial pathogens associated with epidemics of gastrointestinal tract disorders in humans, such as Escherichia coli, Salmonella spp., and Staphylococcus aureus, have evolved multidrug-resistant forms subsequent to antibiotic use [1]
Analyses of heavy metals and fluorine content in the extracts and original plant material revealed that the aqueous extract contained higher levels of lead, cadmium, and fluorine than the plant material and the two extracts prepared from the hydroethanol extractive solution
These results demonstrate that 80% ethanol (v/v) is more efficient for extracting the three flavonoid aglycones and chalcone from the inflorescences than water alone

Summary

Introduction

Many bacterial pathogens associated with epidemics of gastrointestinal tract disorders in humans, such as Escherichia coli, Salmonella spp., and Staphylococcus aureus, have evolved multidrug-resistant forms subsequent to antibiotic use [1]. The extensive use of antibiotics over the last decade has led to the emergence of bacterial resistance and the dissemination of resistant genes among pathogenic microorganisms [2]. Several associations between common chronic human disorders and an altered composition and function of the gut microbiome have been reported [3,4,5,6]. Diseases of the gastrointestinal tract are induced by oxidative stress and overproduction of reactive oxygen species (ROS), which accumulate under abnormal conditions and contribute to the rapid development of inflammation [8]. Many of the chemical constituents of plants, such as flavonoids, have been described as scavengers of the superoxide anion, hydroxyl radicals, and peroxyl radicals, as well as being inhibitors of key enzymes of mitochondrial respiration [9,10,11]

Objectives

Methods

Results

Conclusion