title: Phase partition of gaseous hexane and surface hydrophobicity of Fusarium solani when grown in liquid and solid media with hexanol and hexane.
abstract: The filamentous fungus, Fusarium solani, was grown in liquid and solid culture with glucose, glycerol, 1-hexanol and n-hexane. The partition coefficient with gaseous hexane (HPC) in the biomass was lower when grown in liquid medium with 1-hexanol (0.4) than with glycerol (0.8) or glucose (1) The HPC for surface growth were 0.2 for 1-hexanol, 0.5 for glycerol, 0.6 for glucose, and 0.2 for F. solani biomass obtained from a biofilter fed with gaseous n-hexane. These values show a 200-fold increase in n-hexane solubility when compared to water (HPC = 42). Lower HPC values can be partially explained by increased lipid accumulation with 1-hexanol, 10.5% (w/w) than with glycerol (8.5% w/w) or glucose (7.1% w/w). The diameter of the hyphae diminished from 3 microm to 2 microm when F. solani was grown on solid media with gaseous n-hexane thereby doubling the surface area for gaseous substrate exchange. The surface hydrophobicity of the mycelia increased consistently with more hydrophobic substrates and the contact angle of a drop of water on the mycelial mat was 113 degrees when grown on n-hexane as compared to 75 degrees with glucose. The fungus thus adapts to hydrophobic conditions and these changes may explain the higher uptake of gaseous hydrophobic substances by fungi in biofilters.
authors.affiliation: Departamento de Procesos y Tecnología, Universidad Autónoma Metropolitana-Cuajimalpa, c/o IPH, UAM-Iztapalapa, Av. San Rafael Atlixco No. 186, 09340, México, DF, México. srevah@xanum.uam.mx
authors.forename: Alberto
authors.initials: A
authors.lastname: Vergara-Fernández
authors.forename: Brice
authors.initials: B
authors.lastname: Van Haaren
authors.forename: Sergio
authors.initials: S
authors.lastname: Revah
mesh_terms: D049109:Cell Proliferation / Q000187:drug effects; D003470:Culture Media / Q000737:chemistry / Q000494:pharmacology*; D046508:Culture Techniques; D005670:Fusarium / Q000737:chemistry / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D005740:Gases / Q000737:chemistry; D006586:Hexanes / Q000737:chemistry* / Q000493:pharmacokinetics*; D000441:Hexanols / Q000494:pharmacology*; D057927:Hydrophobic and Hydrophilic Interactions; D007218:Industrial Microbiology / Q000379:methods; D044367:Phase Transition; D013499:Surface Properties / Q000187:drug effects
chemical_list: D003470:Culture Media; D005740:Gases; D006586:Hexanes; D000441:Hexanols; C026385:n-hexane