Anti-Candida and mode of action of two newly synthesized polymers: a modified poly (methylmethacrylate-co-vinylbenzoylchloride) and a modified linear poly (chloroethylvinylether-co-vinylbenzoylchloride) with special reference to Candida albicans and Candida tropicalis

Abstract

Polymeric antimicrobial agents represent a new and important direction that is developing in the field of antimicrobial agents. Antimicrobial activity of two newly synthesized polymers: a modified poly (methylmethacrylate-co-vinylbenzoylchloride) and a modified linear poly (chloroethylvinylether-co-vinylbenzoylchloride) have been investigated and found to be active. Both polymers have showed a broad antimicrobial activity against C. albicans and C. tropicalis. Minimal inhibitory concentrations (MIC's) for poly (methylmethacrylate-co-vinylbenzoyl chloride) were 100, 75 and 100 microg/ml in case of C. albicans (ATCC 2091), C. albicans (SC5314) and C. tropicalis, respectively. However, polycholoroethylvinylether-covinylbenzoylchloride inhibited C. albicans (ATCC 2091), C. albicans (SC5314) and C. tropicalis with minimum inhibitory concentration values (MIC's) of 150 microg/ml against the three tested Candida strains. Mode of action studies of both polymers on the medically important yeasts, C. albicans and C. tropicalis revealed that poly (methylmethacrylate-co-vinylbenzoylchloride) induced cytotoxicity, DNA damage, and altered cell permeability and morphology, which was manifested as aggregated and swollen yeast cells (C. albicans ATCC 2091) by fluorescent microscopy examination. Poly (chloroethylvinylether-co-vinylbenzoylchloride) increased cell permeability, and respiration for C. albicans and C. tropicalis. The tested polymers at 50 microg/ml had pronounced effects on C. albicans and C. tropicalis cell wall phosphopeptidomannane, proteins, sugars and phosphorus. Generally, the two polymers proved effective against the tested microorganisms, but growth inhibitory effect varied according to the composition of the polymer active group. Many investigators consider polymeric antimicrobial agents as a potential new approach for enhancing the efficiency of some existing antimicrobial agents, including prolonged activity, reduce their toxicity, as well as reduce the environmental issues associated with product use.

Antimicrobial activities and mode of action of the selected novel thienopyrimidines derivatives 2-[2-(diphenylmethylene) hydrazino]-5-isopropyl-3-methylthieno [2, 3-d] pyrimidin-4-one

“…They found that thienopyrimidine derivatives inhibits dihydrofolate reductase (DHFR) which plays an essential role in carbon metabolism, which is critical to the biosynthesis of DNA, RNA, and the essential amino acid methionine. However, the effect of the compound no.20 on protein banding pattern in C. albicans coincide with that obtained with Mahmoud and Aly (20). They found that the effect of synthesized polymers modified poly (methylmethacrylate-co-vinylbenzoylchloride) and a modified linear poly (chloroethylvinylether-co-vinylbenzoylchloride) on C. albicans indicated no clear effects in the phosphopeptidomannan molecular weight with main bands at 45, 25 and 15 kDa.…”

“…Poly (chlorethyvinylether-co-vinylbenzoylchloride) increased respiration for C. albicans and C. tropicials (20) as that observed with the effect of the compound no.20 on C. albicans respiration. This effect may be indicates that many chemical compounds interfering directly with electron transfer or uncoupled oxidative phosphorylation from electron transport.…”

“…The compound no. 20 showing reasonable inhibition zones (≥ 20mm) were subjected to determine their minimal MIC value using the twofold serial dilution method recommended by the Clinical and Laboratory Standards Institute (14). The test organisms were grown in their suitable nutrient broth medium for bacteria and sabouraud's medium for fungi at 30 °C for 24 h for bacteria and 48 h at 28 °C for fungi.…”

“…So, the aerobic synthesis of ATP is inhibited and the oxygen uptake is not inhibited (17). Also, it may be indicates a slight effect on the plasma membrane and increasing cells respiration for exhausting the energy compound present inside the cell before its death (20).…”

“…Saloman and Farias (36) found that microcin 25; a peptide antibiotic caused E. coli cell filamentation. Moreover, poly (methyl methacrylate co-vinylbenzoylchloride) altered cell morphology which was manifested as aggregated and swollen yeast cells (C. albicans ATTCC 2091) (20). Simõesc et al (18) found that interference on bacterial cell cycle occurs at high ortho-phtalaldehyde concentrations and cell division is compromised as the cellular septation seems not to occur.…”