Authors:A.I. Korkmaz, H. Akgul, M. Sevindik and Z. Selamoglu
Lichens are symbiotic associations that are formed by fungi and algae or cyanobacteria. The number of lichen species investigated pharmaceutically is still very low at present. The present study aims to determine the antioxidant activities, antibacterial activities, DNA protective activities, and oxidative stress status of Bryoria fuscescens (Gyeln.) Brodo & D. Hawksw., Parmelina tiliacea (Hoffm.) Hale, and Umbilicaria decussata (Vill.) Zahlbr. Lichens were extracted with ethanol in the Soxhlet device. The DPPH method was used to determine antioxidant activities. DNA protective activity was determined using pBR322 supercoil DNA. Antibacterial activity was determined with dilution test on 5 different species of bacteria (Enterocossus faecalis, Klebsiella pneumoniae, Pseudomonas aeruginosa, Escherichia coli, and Staphylococcus aureus). Total antioxidant status (TAS), total oxidant status (TOS), and oxidative stress index (OSI) were defined with Rel Assay Diagnostics kits. It was observed that DPPH free radical scavenging activities in lichen ethanol extracts increased with increasing concentration. The highest antioxidant activity was observed in B. fuscescens and the lowest activity was determined in U. decussata. It was also determined that the ethanol extracts of all lichen samples had DNA-protective activity. The highest antibacterial activity was detected in B. fuscescens, while the lowest activity was detected in U. decussata. It was determined that B. fuscescens had the highest oxidative stress index and U. decussata had the lowest value. It appears that the ethanol extracts of the lichen samples utilized in the study could be used as an alternative and complementary resource in medical treatment.
Authors:H.M. Manav, O. Gurbuz, D. Cumbul, I.E. Tokat, E. Korkmaz and A.F. Dagdelen
Overall and melamine migration have been determined for 60 samples of melamine resin bowls, which were purchased in various local markets in the area of Bursa, Turkey. The samples were exposed to food simulants 3% acetic acid, 10% ethanol aqueous solutions, and rectified (refined) olive oil at 100 °C for 30 min, and 50% ethanol aqueous solutions at 60 °C for 30 min. The LOQ value was calculated as 3.3 mg dm−2 for overall migration and 0.126 mg kg−1 for melamine migration. Research findings did not exceed the limit of overall migration level (10 mg dm−2). Also, melamine levels of all tested items found in the third assays were below the specific migration limit (SML) of 2.5 mg kg−1 set out in the EU 10/2011 (EU, 2011) and Turkish Food Codex 2013/34 (TFC, 2013a). Some expensive as well as cheap products showed close migration levels. The increased cost of the item did not indicate a higher quality regarding health in this study.