Studiul adsorbției bacteriei Bacillus subtilis și a fungului Candida albicans pe enterosorbenți de origine vegetală

Abstract

The paper presents the results of the adsorption of Bacillus subtilis bacteria and Candida albicans fungus on enterosorbents of different vegetal origin. The bacterial specia was grown on nutrient agar and the fungus on the Sabouraud agar for the accumulation of the microbial biomass. As adsorbents in the experiments were used different fractions of: initial activated carbon from apple wood (630-800 μm), reactivated carbon from apple wood (630-800 μm), activated carbon from apricot husks (630-800 μm), charcoal from walnut shells(800 μm - 2000 μm). Calibration curves were established for each microbial species studied. The prepared solutions were then contacted with pre-weighed activated carbon, approximately 100 mg each. The optical densities of the studied samples were measured at a wavelength of 315 nm, subsequently calculated the equilibrium concentrations and the adsorption values. Adsorption isotherms of bacteria were measured after stirring the bacterial solutions of different initial concentrations with carbon adsorbents for 2 hours at a mechanical stirrer. The highest adsorption properties were attested for the activated carbons from apple wood, the values being in the range of 1,25-1,5 McF*108/g that can be explained due to the fact that this carbon adsorbent has a larger amount of macropores.