Lipid accumulation in Trichoderma species

Abstract

Two filamentous fungi, Trichoderma harzianum and Trichoderma viride, were compared for their ability to synthesize lipids on different carbon and nitrogen sources. Three culture media were selected for each strain after preliminary screening. All the test media were nitrogen‐deficient (C/N = 60) so as to stimulate lipid accumulation. For both microorganisms the glucose‐ammonium sulphate medium was the most conducive to lipid production: a lipid accumulation of 17% (w/w) of biomass dry weight was obtained for T. harzianum and of 32% (w/w) of biomass dry weight for T. viride. In sucrose‐sodium nitrate medium T. harzianum was able to accumulate almost 25% (w/w) of its biomass in lipid form. However the small quantity of biomass produced (2 g dry weight/l) limited the quantity of lipid obtained. Neutral lipids, free fatty acids and phospholipids were monitored during 8 days of cultivation of the two fungi.

Lipid content and fatty acid composition of a marine-derived Trichoderma longibrachiatum strain cultured by agar surface and submerged fermentations

“…These values are in agreement with previous studies concerning lipid synthesis by T. viride [8] and T. reesei [24]. Nevertheless, lipid accumulation in Trichoderma terrestrial strains were shown very dependent of different parameters as the culture media composition [10], the pH and the temperature Data are the mean of three replicates AE S.D. a As explained in Section 2, expressed per litre of culture.…”

“…In both culture ways, linoleic acid was the highest FA in TL as well as in PL. Similar amounts of linoleic acid has been reported in other Trichoderma species cultivated in liquid medium as T. reseii (47%) [11] and T. harzianum (48%) [10]. In both fermentations stearic acid was present in smaller levels in PL, showing that it likely does not play any structural role in the cell membrane.…”

“…In our best knowledge, only few studies describe lipid class separation from Trichoderma species so far. Thus, lipid classes produced by T. harzianum and T. viride in glucoseammonium-sulphate medium after a cultivation period of 8 days [10] showed the predominance of neutral lipids (72.9% and 63.2%, respectively) as for T. longibrachiatum in ASF but not in SmF. However, in an early study on lipid synthesis by T. viride, Ballance and Crombie [8] showed that PL were less accumulated when spores were cultivated in glucose-agar slopes (21%) than mycelium cultivated in non-aerated glucose solutions (55%, respectively).…”

“…Spore suspension was prepared with sterile seawater and after filtration, 160 Â 10 6 spores/mL were counted using Malassez cells. About 1 mL of sterile suspension was inoculated in 500 mL flasks (final concentration of 0.5 Â 10 6 spores/mL) and incubated for 10 days according to a previous study of lipid accumulation by Trichoderma species cultivated in liquid cultures [10]. In the latter case, the maximum of the lipid content was observed globally between the 9th and 11th days.…”

“…Primitive fungi such as oomycetes and zygomycetes have been widely investigated and recognized as fungal sources of interesting PUFA such as arachidonic acid (ARA) or eicosapentaenoic acid (EPA) [3][4][5][6][7]. Various terrestrial species from the genus Trichoderma have been already studied for their lipid production [8][9][10][11]. Their major FA were 16:0, 9, 12-18:2, 9-18:1 and 18:0 in concordance with those known to be accumulated in fungi [9].…”