Morphological evolution of various fungal species in the presence and absence of aluminum oxide microparticles: Comparative and quantitative insights into microparticle‐enhanced cultivation (MPEC)

• Published in: MicrobiologyOpen (Weinheim) Vol. 7; no. 5; pp. e00603 - n/a
• Main Authors: Kowalska, Anna, Boruta, Tomasz, Bizukojć, Marcin
• Format: Journal Article
• Language: English
• Published: England John Wiley & Sons, Inc 01.10.2018; John Wiley and Sons Inc
• Subjects: Agglomerates; Agglomeration; Aluminum; Aluminum oxide; Aluminum Oxide - metabolism; Aspergillus - drug effects; Aspergillus - growth & development; Biological evolution; Cell Adhesion; Chaetomium - drug effects; Chaetomium - growth & development; Chaetomium globosum; Cultivation; Digital imaging; Elongation; Enzymes; Experiments; filamentous fungi; Fungi; image analysis; Metabolites; Microparticles; microparticle‐enhanced cultivation; Microscopy; Morphology; morphology engineering; Mucor - drug effects; Mucor - growth & development; Mycelia; Mycelium - drug effects; Mycelium - growth & development; Original; Original Research; Pellets; Penicillium - drug effects; Penicillium - growth & development; Species; Viscosity; microparticle-enhanced cultivation; morphology engineering; filamentous fungi; image analysis
• ISSN: 2045-8827; 2045-8827
• DOI: 10.1002/mbo3.603

The application of microparticle‐enhanced cultivation (MPEC) is an attractive method to control mycelial morphology, and thus enhance the production of metabolites and enzymes in the submerged cultivations of filamentous fungi. Unfortunately, most literature data deals with the spore‐agglomerating species like aspergilli. Therefore, the detailed quantitative study of the morphological evolution of four different fungal species (Aspergillus terreus, Penicillium rubens, Chaetomium globosum, and Mucor racemosus) based on the digital analysis of microscopic images was presented in this paper. In accordance with the current knowledge, these species exhibit different mechanisms of agglomerates formation. The standard submerged shake flask cultivations (as a reference) and MPEC involving 10 μm aluminum oxide microparticles (6 g·L−1) were performed. The morphological parameters, including mean projected area, elongation, roughness, and morphology number were determined for the mycelial objects within the first 24 hr of growth. It occurred that heretofore observed and widely discussed effect of microparticles on fungi, namely the decrease in pellet size, was not observed for the species whose pellet formation mechanism is different from spore agglomeration. In the MPEC, C. globosum developed core‐shell pellets, and M. racemosus, a nonagglomerative species, formed the relatively larger, compared to standard cultures, pellets with distinct cores. A novel study aimed at the quantification of early development of four different fungal species in the submerged shake flask culture was presented. The action of mineral microparticles in the microparticle‐enhanced cultivation to control fungal morphology was studied.