Search results for "enzyme inhibition"

Convergent synthesis and preliminary biological evaluations of the stilbenolignan (±)-aiphanol and various congeners

2003

Treatment of an equimolar mixture of stilbene 7 and cinnamyl alcohol 8 with silver carbonate in acetone–benzene afforded a ca. 2 : 1 : 2 : 1 mixture of the stilbenolignan (±)-aiphanol (1) and congeners 2–4 each of which show significant anti-angiogenic and COX-2 inhibitory properties.

INHIBITION OF POLYPHENOL OXIDASE FROM EGGPLANT.

2005

Laurel extracts inhibit quorum sensing, virulence factors and biofilm of foodborne pathogens

2020

Antimicrobial, antibiofilm, anti-Quorum sensing (QS) and virulence factors inhibitory capacity of different polarity Laurus nobilis extracts against several pathogenic microorganisms were studied. Some extracts exhibited antibiotic effect against Staphylococcus aureus multidrug-resistant strains. However, all extracts (100 µg/mL) inhibited to some extent the biofilm of most bacteria tested (until 40% for Gram-negative and 76% for Gram-positive). Hexane (HE) and chloroform extract (CE) were potent inhibitors of S. aureus biofilm and the microscopies further confirmed an important reduction in adherent cells. Polystyrene surfaces coated with these extracts showed a decrease in bacterial adhes…

Selected cytotoxic gold compounds cause significant inhibition of 20S proteasome catalytic activities

2014

Abstract Six structurally diverse cytotoxic gold compounds are reported to cause profound and differential inhibition of the three main catalytic activities of purified 20S proteasome whilst auranofin , an established gold(I) drug in clinical use, is nearly ineffective. In particular, the gold(I) complex [( pbiH ) Au ( PPh 3 )] PF 6 , turns out to be the most potent inhibitor of all three enzyme activities with sub-micromolar IC 50 values. The present results further support the view that proteasome inhibition may play a major – yet not exclusive – role in the cytotoxic actions of gold based anticancer agents.

Synthesis of tritiated derivatives of the diphenylether herbicides acifluorfen and acifluorfen methyl

1992

Acifluorfen 1 and acifluorfen methyl 2, two herbicides of the diphenylether family, are inhibitors of protoporphyrinogen oxidases. Two tritiated derivatives of these compounds, namely 3-[3H]-5-[2-chloro-4-(trifluoromethyl)phenoxy]-2-nitrobenzoic acid [3H]-1, and methyl 3-[3H]-5-[2-chloro-4-(trifluoromethyl)phenoxy]-2-nitrobenzoic acid [3H]-2, have been synthesised from 3-[3H]-5-hydroxybenzoic acid, in order to probe their interactions with the target enzymes.

A multivariate insight into ionic liquids toxicities

2014

A multivariate insight into Ionic Liquids' (ILs) toxicity, a broad term highly dependent on the biological systems adopted as “sensors”, addressed four main groups of toxicities: aquatic toxicity, toxicity towards fungi and bacteria, cytotoxicity towards IPC-81 rat cell lines and acetylcholinesterase enzyme inhibition. This approach, summarizing toxicity information available from a huge amount of scattered literature data, allowed derivation of aquatic toxicity scores for 104 ILs and bacteria and fungi toxicity scores for 87 ILs as well as identification of a correlation between aquatic ecotoxicity and the response of IPC-81 rat cell lines. Further evidence on the effects of cation structu…

Halloysite nanotubes for efficient loading, stabilization and controlled release of insulin

2018

Hypothesis: Oral insulin administration is not actually effective due to insulin rapid degradation, inactivation and digestion by proteolytic enzymes which results in low bioavailability. Moreover insulin is poorly permeable and lack of lipophilicity. These limits can be overcome by the loading of protein in some nanostructured carrier such as halloysite nanotubes (HNTs). Experiments: Herein we propose an easy strategy to obtain HNT hybrid materials for the delivery of insulin. We report a detailed description on the thermal behavior and stability of insulin loaded and released from the HNTs hybrid by the combination of several techniques. Findings: Release experiments of insulin from the H…

Thymidylate synthases from Hymenolepis diminuta and regenerating rat liver: purification, properties, and inhibition by substrate and cofactor analog…

1995

Comparative studies of thymidylate synthases, isolated from the tapeworm, Hymenolepis diminuta, and regenerating liver of its host, rat, aimed at a possibility of specific inhibition of the helminthic enzyme, are presented. While similar in structure (dimers with monomer molecular masses of 33.7 kDa and 34.9 kDa, respectively) and parameters describing interactions with substrates and products, the tapeworm and rat enzymes differed in the dependences of reaction velocity on temperature (Arrhenius plots biphasic and linear, respectively). The tapeworm, compared with the host, enzyme was less sensitive to the competitive slow-binding inhibition by 5-fluoro-dUMP and its 2-thio congener, but eq…

Enzyme Inhibition Microassays on Blu-Ray Disks for Drug Discovery

2019

[EN] An enzyme inhibition-based assay for drug discovery developed by microarraing on Blu-ray disks is presented. As a proof-of-concept, the system screens a selected molecule library of potential chemical inhibitors against the glycoenzyme peroxidase, identifying the promising lead compounds with high selectivity using standard Blu-ray disks and drives. In order to face the first drug discovery stages, we establish the bases for a high-throughput screening assay and a methodology based on hypersurfaces suitable to manage a high number of data as well.