Antibacterial activity and mechanism of piperazine polymer

Abstract

Piperazine polymers poly(ethylenediaminetetraacetic dianhydride‐co‐piperazine) (PE) and MGF‐Ct24E‐modified poly(ethylenediaminetetraacetic dianhydride‐co‐piperazine) (PEM) showed good antibacterial activity. Considering their different applications, the effects of time, pH, and inoculation concentration of these antibacterials against Escherichia coli (E. coli) in unique environments were evaluated in this study. The results indicated that the MIC and MBC values of the polymers increased after the introduction of MGF‐Ct24E into PE, but the two types of polymers still exhibited good antibacterial activity in a short time period under acidic conditions. In addition, we investigated the effect of the piperazine polymers on bacterial cell structure. It was clear that PE and PEM could destroy the bacterial cell wall, cell membrane and DNA, and their specific mechanism may be different. For PE, its carboxyl group could react with peptidoglycans on the E.coli cell wall to form holes on the bacterial surface, allowing PE to penetrate into the bacterial cell to damage DNA. For PEM, the alkaline MGF‐Ct24E could adsorb E.coli and make it shrink, meanwhile, the PE component created small holes on the bacterial walls and membranes, and inserted into the bacteria to result in bactericidal effect. These findings reveal the potential usefulness of PE and PEM in biomedical applications.

Discovery of diversified cassane diterpenoids as potent antibacterial agents from Caesaplinia pulcherrima and their mechanisms

“…β ‐Galactosidase is widely found in various bacterial cells. When the inner membrane of a bacterium is destroyed, β ‐galactosidase will seep out into the culture medium, catalyzing a specific substrate, ONPG, to produce o‐nitrophenol (ONP), which exhibits strong absorption at 420 nm 23 . The effect of capulchemin A on the cell membrane permeability of Psa and B. cereus was therefore investigated by determining the content of extracellular β ‐ d ‐galactosidase (Fig.…”

“…Referring to the reported method by Zhang et al 23 the integrity of the bacterial membrane can be evaluated by measuring the changes in corresponding substances in the culture medium over time. Psa and B. cereus were fostered the mid-log phase in LB medium at 180 rpm and 37 °C.…”

Building Up a Piperazine Ring from a Primary Amino Group via Catalytic Reductive Cyclization of Dioximes

“…Moreover, the piperazine ring is the key structural motif in several blockbuster drugs, including Gleevec (Imatinib) and Viagra (Sildenafil). Apart from medical use, piperazines are commonly applied as pesticides [4], ligands in catalysts [5], CO 2 -capturing materials [6], as building blocks in crystal design [7,8], and in polymer production [9,10].…”

Antifouling and Antibacterial Surfaces Grafted with Sulfur-Containing Copolymers

“…In addition to antifouling materials, the development of antibacterial materials capable of inhibiting attachment or killing approaching microorganisms is a topic of constant interest. − Although antibiotics are still the most common strategy to combat bacterial infection, the development of drug resistance causes significant loss in the effectiveness of antibiotics after long-term usage and has aroused a wide public concern. − As such, alternative antibacterial agents, especially polymeric antibacterial materials that can inhibit the growth of bacteria via various mechanisms, have received increasing attention. − Among these, synthetic cationic polymers demonstrate remarkable bacterial inhibitory efficacy by disrupting negatively charged bacterial cell walls through electrostatic interactions, representing an important class of non-antibiotic polymeric antibacterial agents not susceptible to development of drug resistance. − These polymers with varied chemical structures, low toxicity, and high antibacterial efficacy are promising to enable various antibacterial applications. ,− The majority of these cationic polymers carry quaternary ammonium groups as the functional moieties to exert antibacterial action. − In contrast to quaternary ammonium groups, sulfonium groups, a class of sulfur-based cationic species, have also been reported to demonstrate antibacterial properties. − However, limited research has been devoted to investigate the antibacterial activity of polymeric sulfonium groups.…”