Evaluation of Chemical and Mineralogical Structure of Davutoğlan Bird Sanctuary Clay for It’s Antimicrobial Efficiency

Abstract

In this study we examined possible antimicrobial properties of clay specimen taken from Davutoğlan Bird Sanctuary which is located in Kıztepe skirts as a remote ecological environment to industrial areas. Antimicrobial effects of Gram (-) (Escherichia coli, Pseudomonas aeruginosa) and Gram (+) (Bacillus subtilis, Enterococcus faecalis, Staphylococcus aureus) pathogenic bacteria species on clay samples collected from the region were investigated. Between 0.5-1.5 g/mL concentration range clay has been shown to affect bacterial growth with the bacterial inoculations of 105 cfu/mL. X-ray diffraction (XRD), X-ray fluorescence (XRF) and thermogravimetric (TG) studies of clay minerals and chemical structure have been determined in parallel with the study of antimicrobial activity in order to support these results and to explain the findings. In addition, scanning electron microscopy (SEM) and Brunauer–Emmett–Teller (BET) methods were used to determine the pore structure and surface area of the clay. The obtained results were correlated with antimicrobial activity. According to XRD, XRF and TG analysis results, illite, dolomite and calcite were found to be major clay minerals from the samples taken from the area. It was found that they have a large surface area of 57,002 m2/g according to BET results. It is also concluded that since the large surface area gives strong absorbent properties and supplies a suitable interface for oxidation, suppression of the bacterial growth is observed.