The production of myco-diesel hydrocarbons and their derivatives by the endophytic fungus Gliocladium roseum (NRRL 50072)

Abstract

An endophytic fungus, Gliocladium roseum (NRRL 50072), produced a series of volatile hydrocarbons and hydrocarbon derivatives on an oatmeal-based agar under microaerophilic conditions as analysed by solid-phase micro-extraction (SPME)-GC/MS. As an example, this organism produced an extensive series of the acetic acid esters of straight-chained alkanes including those of pentyl, hexyl, heptyl, octyl, sec-octyl and decyl alcohols. Other hydrocarbons were also produced by this organism, including undecane, 2,6-dimethyl; decane, 3,3,5-trimethyl; cyclohexene, 4-methyl; decane, 3,3,6-trimethyl; and undecane, 4,4-dimethyl. Volatile hydrocarbons were also produced on a cellulose-based medium, including heptane, octane, benzene, and some branched hydrocarbons. An extract of the host plant, Eucryphia cordifolia (ulmo), supported the growth and hydrocarbon production of this fungus. Quantification of volatile organic compounds, as measured by proton transfer mass spectrometry (PTR-MS), indicated a level of organic substances in the order of 80 p.p.m.v. (parts per million by volume) in the air space above the oatmeal agar medium in an 18 day old culture. Scaling the PTR-MS profile the acetic acid heptyl ester was quantified (at 500 p.p.b.v.) and subsequently the amount of each compound in the GC/MS profile could be estimated; all yielded a total value of about 4.0 p.p.m.v. The hydrocarbon profile of G. roseum contains a number of compounds normally associated with diesel fuel and so the volatiles of this fungus have been dubbed 'myco-diesel'. Extraction of liquid cultures of the fungus revealed the presence of numerous fatty acids and other lipids. All of these findings have implications in energy production and utilization.

Evaluation of Cellulose as a Substrate for Hydrocarbon Fuel Production by <i>Ascocoryne sarcoides</i> (NRRL 50072)

“…An empty cell indicates the compound was not detected. * VHC compounds detected previously from A. sarcoides; (iso) = isomer detected [5]- [7] [18]. 1.…”

“…The total number of acids changed negligibly with age, and the same acids were produced in both time periods with only a few exceptions. Butanoic acid, 3-methyl-, C 5 , was only detected from days 5-17. Hexanoic acid (C 6 ) and the longest carbon chain acid at C 12 , 5-decen-1-ol, acetate, were only observed from days 17-32.…”

“…Ascocoryne sarcoides (NRRL 50072) is a cellulolytic fungal endophyte capable of direct conversion of cellulosic materials to fuel-related hydrocarbon compounds such as alkanes, alcohols and aromatics [5] [6]. A. sarcoides was one of the first discovered endophytic fungi with fuel-related compound production in the C 5 -C 10 carbon chain length range.…”

Tailoring next-generation biofuels and their combustion in next-generation engines

“…These organisms naturally live in symbiosis with woody plants, consuming some of the biomass of the host plant and producing volatile organic compounds, many of which are potentially useful fuels. [6][7][8][9] Moreover, because the endophytes produce these useful compounds "directly" from woody biomass, harnessing their metabolic pathways brings the potential for consolidation of the lignocellulose deconstruction and the sugar conversion into one process, promising substantial cost savings. The natural products of endophytic fungal metabolism include ketones, cyclic ethers and other complex oxygenates, whose combustion performance…”

“…In recent years, novel endophytic fungi isolated from rainforests have been shown to produce metabolites touted to be compatible with existing fuels. 6,7,9,[14][15][16] Several of these fungal isolates produce short-to mid-chain aliphatic hydrocarbons, alcohols, and isoprenoids, which could be potential replacements for diesel or fuel additives. 17 In addition, because of their ecologically unique lifestyle (e.g., efficient plant colonization), endophytes possess the necessary chemi-enzymatic machinery to breakdown and utilize lignocellulosic biomass.…”