Investigation of the anti-amyloidogenic and antioxidant effects of silver nanoparticles synthesised with leaf extract of Thymus kotschyanus Boiss

The extract of Thymus kotschyanus Boiss, in addition to its antioxidant properties, also has a marvellous anti-amyloidogenic effectthat can be used for the treatment of amyloidosis. The aim of this study was to prepare silver nanoparticles from the aqueous extract of mountain thyme (Thymus kotschyanus Boiss), to investigate its antioxidant and inhibitory effect on the production of amyloid nanofibrils (bovine serum album (BSA) as a model protein).

This study was conducted experimentally in the laboratory of Payam Noor University in Qom Province in 2022. First, nanoparticles were prepared from aqueous thyme extract and added to AgNo3 silver nitrate solution (one millimolar). ThenFTIR, EDX, DLSand SEM methods were used to study the properties and size of the nanoparticles. The removing of free radicals 2,2-diphenyl-1-picrylhydrazyl (DPPH) method was used to study the antioxidant effects of the extract and the Concorde absorption method was used to study the production of amyloid nanofibrils. The chemical composition of the extract was analysed using the gas chromatography method. For statistical analysis, descriptive statistics and ANOVA tests were used with SPSS software version 23.

The phytochemical analysis of the extract revealed seven compounds. Most compounds were associated with 5,4-alpha-epoxy-3-methoxy (43.53%), 2-ethyl-piperidine-1-methyl (31.02%) and thymol (23.65%). The UV-Vis spectrum showed the highest absorbance at 460 nm. The SEM results confirmed the production of spherical nanoparticles with a size of 70-93 nm. The concentrations of 0.8 and 1 mg/ml of the extract were able to inhibit DPPH by more than 50%. The highest antioxidant activity in the sample containing 2 ml of the nanoparticle solution (sample 5) was 56.82%. The highest inhibition of amyloid nanofibril production was observed at a concentration of 2 mg/ml with 95%.

Thus, the synthesized nanoparticles have potent antioxidant and anti-amyloidogenic properties and can be used as antioxidants.