Biodiversity Evaluation of Geotrichum candidum Link. Is Arthrosporic Nucleus Number in Geotrichum candidum related to the Fungus Biodiversity?

Abstract

Geotrichum candidum species exhibits properties of both moulds and yeasts and its affiliation to one of the groups has been intensively discussed. It is because this filamentous microscopic fungus is displaying substantial morphological variability and wide phenotypic diversity. The present study assesses the variability of arthrosporic nucleus number of twelve isolates of G. candidum originating from artisanal manufacturing and ripened traditional Slovak cheeses. Results showed that arthrospores of the studied isolates contained on average 1.5 ± 0.7 (on the Gorodkova medium) and 1.5 ± 0.6 (on the McClary medium) Hoechst 33258-stained nuclei (range 1–4 nuclei on both agars) after a 7-day cultivation at 25°C. Majority of arthrospores comprised one nucleus, irrespective to the used nutrient-limited medium. Generally, a higher relative nucleus number per arthrospore was exhibited in yeast-like isolates with microscopic structure composed predominantly of spores, while it was lower in vegetative hyphae. These isolates originated from ewe’s lump cheese. Our study reveals that the arthrosporic nucleus number of the G. candidum strains is closely related to morphotype and origin of this yeast.

Modelling the Radial Growth of Geotrichum candidum: Effects of Temperature and Water Activity

“…Geotrichum candidum can contaminate processed foods and adversely affect their nutritional quality through physical, chemical, and sensorial changes. Having mouldy and yeasty properties, G. candidum significantly affects the flavour, aroma, colour and texture of fresh cheeses, butter, fermented milk, cream, poultry meat, fruit juices and vegetables [ 4 , 5 , 6 , 7 , 8 ].…”

“…In Camembert-type cheese, it undergoes mycelial growth, thus supporting Penicillium camemberti , protects food surfaces against contamination and produces enzymes, all of which contribute to proper ripening [ 9 , 10 ]. G. candidum is frequently used during the maturation and flavouring of mould-ripened cheeses (Camembert, Brie, St. Marcellin), blue-veined cheeses (Danablu, Roquefort, Stilton, Gorgonzola) and smear-ripened cheeses (Limburger, Münster, Livarot, Tilsit, Reblochon, Pont-l’Évêque cheese) [ 6 , 11 , 12 , 13 , 14 , 15 ]. In the Scandinavian drink Viili, it is one of the components of the starter culture used for the fermentation of this dairy product [ 16 ].…”