Morphological quantification of filamentous fungal development using membrane immobilization and automatic image...

Area of Science:

• Microbiology
• Biotechnology
• Industrial Fermentation

Background:

• Mycelial morphology is crucial for productivity in industrial fermentations of filamentous microorganisms.
• Accurate quantification of complex fungal morphologies remains a significant challenge.
• Understanding morphology-phenotype-productivity relationships is key to optimizing fermentation processes.

Purpose of the Study:

• To develop and validate a high-resolution image analysis system for characterizing filamentous fungal growth on solid substrates.
• To quantify the microscopic development of Aspergillus oryzae, linking morphology to growth kinetics.
• To assess the robustness of the developed image analysis system.

Main Methods:

• Utilized membrane immobilization and automated plug-ins for Java-based ImageJ software.
• Quantified spore projected area, circularity, hyphal element length, tip number, and hyphal growth unit.
• Analyzed growth stages from spore swelling to branched hyphae over 24 hours.

Main Results:

• Spore swelling increased linearly with time; widespread germination observed by 8 hours.
• Hyphal tip number increased exponentially from approximately 12 hours.
• Calculated specific growth rate of 0.24-0.27 h⁻¹, noting significant population variation.

Conclusions:

• The developed image analysis system provides high-resolution characterization of fungal morphology.
• The system accurately quantifies key growth parameters, enabling better understanding of morphology-productivity relationships.
• This tool facilitates optimization of industrial fermentation processes by providing detailed insights into microbial development.