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julio 6, 2021

Phytochemical, antiplasmodial, cytotoxic and antimicrobial evaluation of a Southeast Brazilian Brown Propolis produced by Apis mellifera bees

Seven phenolic compounds (ferulic acid, caffeic acid, 4-methoxycinnamic acid, 3,4-dimethoxycinnamic acid, 3-hydroxy-4-methoxybenzaldehyde, 3-methoxy-4-hydroxypropiophenone and 1- O ,2- O -digalloyl-6- O -trans- p -coumaroyl-β-D-glucopyranoside), a flavanonol (7- O -methyl aromadendrin), two lignans (pinoresinol and matairesinol) and six diterpenic acids/alcohol (19-acetoxy-13-hydroxylabda-8(17),14-diene, totarol, 7-oxodehydroabietic acid, dehydroabietic acid, communic acid and isopimaric acid)…

PEGylated Oligothioetheramide Prodrugs Activated by Host Serum Proteases

Due to the increasing prominence of antibiotic resistance, novel drug discovery and delivery approaches targeting bacteria are essential. In this work we evaluate a prodrug design to improve the cytotoxic profile of polycationic oligothioetheramides (oligoTEAs), which are promising antimicrobials. Herein we chemically modify the oligoTEA, PDT-4G, with a polyethylene glycol (PEG) and show that 1, 2, and 5 kDa PEGs mitigate cytotoxicity. As PEGylation reduces antibacterial activity, we evaluate…

Strategic approach of multifaceted antibacterial mechanism of limonene traced in Escherichia coli

Antibacterial potential of Limonene against Multi Drug Resistant (MDR) pathogens was studied and mechanism explored. Microscopic techniques viz. Fluorescent Microscopy (FM), Scanning Electron Microscopy (SEM), and Transmission Electron Microscopy (TEM) indicated membrane disruption, cellular leakage and cell death of Escherichia coli (E. coli) cells when treated with limonene. Leakage of intracellular proteins, lipids and nucleic acid confirmed membrane damage and disruption of cell permeability…

Open Label Randomized Controlled Comparison of Three Alternative Regimes of Ciprofloxacin, Azithromycin and Cefixime for Treatment of Uncomplicated Typhoid Fever in Bangladesh

Multi-drug resistant Typhoid fever (resistant to previously used chloramphenicol, ampicillin, amoxicillin, and trimethoprim-sulfamethoxazole) has been commonly described in the South East Asia region and a recent report suggests that the salmonella typhi have reduced response to fluoroquinolones (nalidixic acid-resistant). The optimum treatment protocol for this type of serovar has not been established. This study compared different antimicrobial regimens for the treatment of uncomplicated…

Drug-Lead Anti-tuberculosis Phytochemicals: A Systematic Review

Today, the occurrence and recurrence of multidrug-resistant tuberculosis (MDR-TB) strains and TB-comorbidity incidence are the main reasons for long-term morbidity and mortality from tuberculosis (TB) caused by the nasty acid-fast pathogen, Mycobacterium tuberculosis, globally. Therefore, discovering and developing well-tolerated and non-toxic anti-TB regimens are directly needed to defend the gruesome MDR-TB strains and support WHO’s ‘END-TB’ campaign. Alternatively, phytochemicals from various…

A scaffolded approach to unearth potential antibacterial components from epicarp of Malaysian Nephelium lappaceum L

The emergence and spread of antimicrobial resistance have been of serious concern to human health and the management of bacterial infectious diseases. Effective treatment of these diseases requires the development of novel therapeutics, preferably free of side effects. In this regard, natural products are frequently conceived to be potential alternative sources for novel antibacterial compounds. Herein, we have evaluated the antibacterial activity of the epicarp extracts of the Malaysian…

Comparative study of the difference in behavior of the accessory gene regulator (Agr) in USA300 and USA400 Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA)

Community-associated Methicillin-Resistant Staphylococcus aureus (CA-MRSA) is notorious as a leading cause of soft tissue infections. Despite several studies on the Agr regulator, the mechanisms of action of Agr on the virulence factors in different strains are still unknown. To reveal the role of Agr in different CA-MRSA, we investigated the LACΔagr mutant and the MW2Δagr mutant by comparing LAC (USA300), MW2 (USA400), and Δagr mutants. The changes of Δagr mutants in sensitivity to oxacillin…