Vegetable oils as carbon and energy source for Aureobasidium melanogenum in batch cultivation

Abstract

Dark homogenous fungal‐based layers called biofinishes and vegetable oils are key ingredients of an innovative wood protecting system. The aim of this study was to determine which of the vegetable oils that have been used to generate biofinishes on wood will provide carbon and energy for the biofinish‐inhabiting fungus Aureobasidium melanogenum , and to determine the effect of the oil type and the amount of oil on the cell yield. Aureobasidium melanogenum was cultivated in shake flasks with different types and amounts of carbon‐based nutrients. Oil‐related total cell and colony‐forming unit growth were demonstrated in suspensions with initially 1% raw linseed, stand linseed, and olive oil. Oil‐related cell growth was also demonstrated with raw linseed oil, using an initial amount of 0.02% and an oil addition during cultivation. Nile red staining showed the accumulation of fatty acids inside cells grown in the presence of oil. In conclusion, each tested vegetable oil was used as carbon and energy source by A. melanogenum . The results indicated that stand linseed oil provides less carbon and energy than olive and raw linseed oil. This research is a fundamental step in unraveling the effects of vegetable oils on biofinish formation.

Production of filamentous fungal biomass with increased oil content using olive oil as a carbon source

“…Spore germination was not observed in the treatments with missing nitrogen sources, trace metals, salts, minerals and vitamins (treatments 1–3, Table 2), irrespective of the fungal strains (Table 1) when olive oil was used as sole carbon source in the medium. Fungi require different growth‐supporting components such as carbon and nitrogen sources, trace metals, salts, minerals and vitamins 1 …”

“…Glucose is the major source of carbon and energy for fungi; however, for optimal growth, other nutrients such as vitamins and minerals need to be provided along with carbon. Olive oil is a potential carbon source for fungi since it is composed of 60% carbon 1 . The effect of different oil concentrations has been tested on the growth of A. oryzae .…”

“…Fungi require different growth-supporting components such as carbon and nitrogen sources, trace metals, salts, minerals and vitamins. 1 Spore germination into visible hyphae was observed in treatment 4 (Table 2) when the full medium was used (olive oil, nitrogen source, salts, vitamins and minerals); however, in such condition and with an imbalanced nutrient mixture, the fungi failed to build a macroscopic and dense mycelial network. Although olive oil does have a high quantity of phenolic compounds that have been reported to inhibit bacterial and fungal growth, 27 yet other factors may have hampered the growth of filamentous fungi in the above medium treatment.…”

“…Olive oil is a potential carbon source for fungi since it is composed of 60% carbon. 1 The effect of different oil concentrations has been tested on the growth of A. oryzae. The concentration of olive oil was varied (0-100 g L −1 ).…”

Bioinspired Living Coating System in Service: Evaluation of the Wood Protected with Biofinish during One-Year Natural Weathering

“…Timber products are currently treated at an industrial scale and the do-it-yourself (DIY) coating formulation is available on the market [43]. A combined effect of wood species, oil types, and material climate conditions on the formation of a uniform biofilm were studied previously [42,44,45]. Nevertheless, several aspects regarding protection mechanisms and the durability of biofinish are still poorly understood.…”