Susceptibility of virulent and resistant Escherichia coli strains to non-polar and polar compounds identified in Microplumeria anomala

Abstract

Background and Aim: Escherichia coli is one of the main pathogens responsible for veterinary and human infections, and it is associated with significant economic losses in the livestock, as it causes severe diseases to humans, particularly in children. For that reason, there is a need for introducing new drugs to treat E. coli diseases. The Brazilian species richness is a source of potential new antibacterial natural products. The study aimed at the biological and chemical investigation of the organic extract obtained from the stem of Microplumeria anomala (Apocynaceae), EB127, as it was identified as a potential source of new antibacterial compounds to be used in Veterinary. Materials and Methods: The antibacterial activity was evaluated by disk diffusion and microdilution assays; chromatography, nuclear magnetic resonance spectrometry, and mass spectrometry were used in the isolation and identification of compounds. Results: EB127 showed activity against E. coli ATCC25922, and against three E. coli strains that were isolated from frigarte's cloaca, named 31/1A, 35A, and 51A. Lupeol, 3-acetyl-11-oxo-β-amyrin, 3-acetyl-11-oxo-α-amyrin, sitosterol, stigmasterol, 3β,7α-dihydroxy-cholest-5-ene, 3β-hydroxy-cholest-5-en-7-one, and 3β-hydroxy-cholest-5,22-dien-7-one were identified in fraction Hex/CHCl3, while loganin, loganic acid, methylanomaline, and anomaline were all identified in EB127 and protocatechuic acid hexoside, ferulic acid, secoxyloganin, feruloylquinic acid, vanillic acid hexoside, protocatechuic acid-4-O-β-hexoside, and rosmarinic acid were tentatively identified in fraction 10%ACN/H2O. E. coli 51A (virulent/non-resistant) showed sensitivity to the antibacterial action of fraction Hex/CHCl3 which contains alkaloids, triterpenes, and steroids, while E. coli 35A (resistant/non-virulent) were more susceptible to 10%ACN/H2O, which contains iridoids as loganin and loganic acid, and glycosylated and non-glycosylated caffeic acids. Conclusion: Fraction 10%ACN/H2O is of interest in pursuing new drugs to treat resistant E. coli, in veterinary. All compounds were isolated from the plant for the first time and have shown potential as new antibacterial natural products from Amazon plants to be used in veterinary and human diseases.

Screening Amazon rainforest plant extracts for antimicrobial activity: a 15-year commitment to the Brazilian biodiversity

“…In recent decades, our researchers have been systematically developing projects aiming to identify antimicrobial active extracts from the Amazon and Atlantic Brazilian rainforests. We have studied more than 2,000 plant extracts and essential oils as antimicrobials against Staphylococcus aureus (Pinto, 2020), Staphylococcus epidermidis (Belo, 2022), Enterococcus faecalis (Castilho, 2009), Streptococcus mutans (Bento, 2020), Streptococcus sanguinis (Silva, 2009), Escherichia coli (Camargo, 2016), Pseudomonas aeruginosa, Candida albicans (Rudiger, 2021), Malassezia pachydermatis (Silva, 2018), Malassezia furfur ( Silva, 2018 ), and Listeria monocytogenes (Ceruso et al, 2020), which are shown in the present article as a result of a 15-year study in antimicrobial-active natural product identification (Suffredini et al, 2002;Suffredini et al, 2004;Suffredini et al, 2006a;Suffredini et al, 2006b;Younes et al, 2007;Castilho et al, 2013;Camargo and Suffredini, 2014;Castilho et al, 2014;da Silva et al, 2014;Costa et al, 2016;Suffredini et al, 2016;Martins et al, 2019a;Martins et al, 2019b;Camargo et al, 2020;Silva et al, 2020).. The present article reports a step-by-step methodology for identifying antimicrobial products in nature that comprises plant collection, the different tests used to analyze the in vitro antimicrobial activity, a test to determine toxicity, and a statistical-based algorithm to classify the extracts according to their potential.…”

“…To optimize the costs of the random-chemotaxonomic plant collection strategy, small amounts of plant material are collected in the field, resulting in small amounts of plant extracts, so it is vital to adjust the in vitro assay scales to the use of micrograms of plant extracts A proposed ranking of 111 plant extracts according to their antimicrobial activity efficacy and low toxicity. Suffredini et al 10.3389/frabi.2023.1122400 Frontiers in Antibiotics frontiersin.org (Suffredini et al, 2002;Suffredini et al, 2004;Suffredini et al, 2006a;Suffredini et al, 2006b;Younes et al, 2007;Castilho et al, 2013;Camargo and Suffredini, 2014;Castilho et al, 2014;da Silva et al, 2014;Costa et al, 2016;Suffredini et al, 2016;Martins et al, 2019a;Martins et al, 2019b;Camargo et al, 2020;Silva et al, 2020).…”

Secondary Metabolites of Osmanthus fragrans: Metabolism and Medicinal Value

“…It normally exists as a solid and needs to be stored at low temperatures. Secoxyloganin has anti-inflammatory, vasoconstriction, antiviral, antitumour and antibacterial activities ( Camargo, et al, 2020 ). While identifying the sensitizing components in reducing injection by ultrafiltration and high-performance liquid chromatography.…”