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This study aims to investigate the effect of different pore diameter and pore length on corrosion properties of anodic aluminum oxide (AAO) film.

AAO layer was produced by two-step anodization aluminum in oxalic acid. The surface morphology was investigated using field emission scanning electron microscopy. The pore diameters were ranging from 25 ± 5 to 65 ± 5 nm and the pore length ranging from 5 to 17 µm. The corrosion properties of the AAO films was analyzed by potentiodynamic polarization and electrochemical impedance spectroscopy tests. Corrosion properties and morphology of the anodic films depending on anodization times and pore expansion times were evaluated.

All highlights of this work can be summarized with the following specified below: more treatment with the protective barrier layer of the solution as the pore diameter increases depends on the morphology of the nanotube structured AAO layer. The excellent corrosion resistance renders AAO films without pore expansion very promising. The oxide layer thickness does not affect the corrosion resistance. The better corrosion resistance of AAO films at low pore length can be ascribed to the barrier layer thickness and the more homogeneous structure. The presence of defects for the higher pore length decreases its corrosion resistance.

The AAO films were fabricated by a two-step anodization method in oxalic acid. The anodization times and pore expansion times affect the corrosion performance. The AAO film without pore expansion has good corrosion resistance. The corrosion resistance decreases as the pore length increases.

Mushrooms have always been treasured and appreciated, thanks to their nutritional as well as medicinal properties. The purpose of this paper is to reveal these properties such as antioxidant activities and enzyme inhibition potentials of three mushroom species from Ordu, Turkey. Furthermore, phenolic profiles which are believed to be source of these properties are investigated.

The assays followed to determine total phenolic, flavonoid and antioxidant contents, antioxidative and enzyme inhibition activities are spectrophotometric methods. Phenolic profiles of mushroom samples were investigated by using the HPLC system.

The highest phenolic content was found for Lactarius deliciosus. Pyrogallol was the major phenolics in all three samples. Total phenolic content values supported that finding. But, total flavonoid content was the maximum for Cantharellus cibarius. The magnitude of the antioxidant activities revealed by the different tests varied between species. Furthermore, inhibition potential degrees on acetylcholinesterase, butrylcholinesterase, tyrosinase and urease activities were worth mentioning. Lactarius pyrogalus had anti-tyrosinase activity with a 26.229 percent inhibition rate. IC₅₀ values for urease inhibition effect of mushroom samples were in the range of 0.37–0.90 mg/mL.

Enzyme inhibitory potentials for L. pyrogalus was revealed first time. On the other hand, studies on anti-tyrosinase activity of mushrooms are very rare, while almost no studies have been conducted on anti-urease activity. So, the results of present study are very valuable. Thus, the obtained data not only increase the ecological importance of the region but also provide significant contributions to the literature in terms of new sources rich in antioxidants.