Use of confocal scanning laser microscopy to measure the concentrations of aerial and penetrative hyphae during growth of Rhizopus oligosporus on a solid surface

Abstract

In order to develop a method for use in investigations of spatial biomass distribution in solid-state fermentation systems, confocal scanning laser microscopy was used to determine the concentrations of aerial and penetrative biomass against height and depth above and below the substrate surface, during growth of Rhizopus oligosporus on potato dextrose agar. Penetrative hyphae had penetrated to a depth of 0.445 cm by 64 h and showed rhizoid morphology, in which the maximum biomass concentration, of 4.45 mg dry wt cm(-3), occurred at a depth of 0.075 cm. For aerial biomass the maximum density of 39.54 mg dry wt (-3) occurred at the substrate surface. For both aerial and penetrative biomass, there were two distinct regions in which the biomass concentration decayed exponentially with distance from the surface. For aerial biomass, the first exponential decay region was up to 0.1 cm height. The second region above the height of 0.1 cm corresponded to that in which sporangiophores dominated. This work lays the foundation for deeper studies into what controls the growth of fungal hyphae above and below the surfaces of solid substrates.

Oxygen profiles and biomass distribution in biopellets of Aspergillus niger

“…In biofilm research, confocal laser scanning microscopy (CLSM) has been applied to quantify volumetric shares of bacteria and extracellular polymeric substances (Boessmann et al, 2003(Boessmann et al, , 2004Staudt et al, 2003Staudt et al, , 2004. Concerning fungal morphology, hyphal distributions of Rhizopus oligosporus were analyzed in solid-state cultivations and quantified by CLSM and image analysis (Nopharatana et al, 2003). To our knowledge, there has not been any investigation, where this tool was applied for the quantification of fungal pellet structures.…”

Biomass measurement by flow cytometry during solid‐state fermentation of basidiomycetes

“…As a result, direct biomass determination is deemed impossible and indirect methods must be used. Indirect biomass measurements can be obtained using a range of physical techniques such as scanning electron microscopy (7,8), epifluorescence microscopy (9), and measurements of temperature changes, effluent gas composition, or light reflectance (2,10). Alternatively, they can be acquired using biochemical methods.…”

Gradientes, permeabilidad y balance de materia en cultivos superficiales de Aspergillus niger

“…Más bien, se extiende hacia arriba de la superficie sólida con una densidad que decrece como una función exponencial de la coordenada vertical (z). Nopharatana et al (2003), Oostra et al (2001) 2001; Camacho-Díaz et al, 2010) pero es el mismo del modelo de Nopharatana et al, (1998). Esta discrepancia pudiera deberse al tipo de respiración de cada organismo.…”

“…Esto permite ligar los dos procesos: una reducción del rendimiento, YX/S, y el aumento del metabolismo anaerobio (Diano et al, 2006). Cabe mencionarse que, si bien el espesor de la biocapa ya ha sido medida (Oostra et al, 2001;Nopharatana et al, 2003)…”

“…La tendencia de esos valores siguió una relación hiperbólica bien definida (R 2 = 0.9613).  se le llama supremo porque es el máximo de A para todos los experimentos y se obtiene cuando 0 es muy grande y el sustrato ha V, aproximadamente uniforme hasta alcanzar un espesor máximo h, que es una función de saturación de 0 y que alcanza un valor supremo hsup.Los datos aquí presentados indican que A. niger tiene un modelo de crecimiento con densidad de micelio uniforme que es distinto al de Rhizopus oligosporus que estudiado ampliamente por otros autores(Nopharatana et al, 2003;Oostra et al,…”