Investigation of Physicochemical Characteristics of Aspergillus niger Biomass and Examination of Its Ability to Separate Butyl Acetate Isomers

Abstract

Aspergillus niger is a species of fungus that is widely found in natural ecosystems and has an important role in various industrial fields and is readily available. To study the adhesion of microbial cells to solid substrates and to improve their properties, physicochemical characterization of microorganisms is extremely important. For this purpose, in this study, the surface properties of A. niger biomass were determined at low cost and with high accuracy by inverse gas chromatography (IGC), a physicochemical characterization technique. IGC experiments were conducted between 303.2 and 328.2 K at infinite dilution. Among these temperatures, various organic solvent vapors were passed over the A. niger biomass considered as stationary phase and their retention behavior was studied. Using the raw data, net retention volumes were calculated and retention diagrams were drawn. From the linear retention diagrams, the dispersive surface energy was calculated according to Dorris-Gray (48.73-46.09 mJ/m(2)), Donnet-Park (47.12-44.50 mJ/m(2)), Schultz (46.88-42.45 mJ/m(2)), and Hamieh (76.42-64.06 mJ/m(2)) methods. With the IGC method, the acidity-basicity parameters of A. niger biomass were determined and it was found that the surface was basic (K-D/K-A=4.871). In the second part of this study, the butyl acetate isomer series, which are difficult to be separated by conventional methods, were effectively separated by the IGC method using A. niger stationary phase.