Hormoconis resinae

Varshney, R., Mishra, A.N., Bhadauria, S., and Gaur, M.S. 2009. A novel microbial route to synthesize silver nanopartilces using fungus Hormoconis resinae. Digest Journal of Nanomaterials and Biostructures, 4 349-55. 

Fig. (23). Structure of3p-hydroxy-l,l l-dioxo-ergosta-8,24(28)-diene-4a-carboxylicacid isolated from Hormoconis resinae...

We have become dependent on the use of petroleum fuels to provide heat, power equipment and provide transportation. This has led to a concern that there could be an interruption in a secure, adequate supply of crude oil needed to manufacture these fuels. Continued reports of microbial contamination in petroleum fuels have also caused concern. Scientists have been evaluating the use of alternate sources to petroleum to prepare fuel (synthetic fuels) such as oil shale, tar sands and coal. Studies of the microbial susceptibility of Jet JP-5 and diesel fuels prepared from these alternate sources demonstrated that the synthetic fuels would not support more microbial contamination than their petroleum-derived fuel counterparts and that fuel derived from pyrolyzed coal may even have fewer problems (May and Neihof, 1982). Coal JP-5 jet fuel inhibited growth of Hormoconis resinae and Candida spp. (caused by constituents in the coal-derived fuel that have not been identified) (Neihof and May, 1984). 

In reality, the fuel storage tank is a two-phase system - a fuel phase and a water bottom phase. Some bacterial cells and fungal spores can survive dormant in dry fuel for months to several years Hormoconis resinae) (Gardner, 1971). However, cells can only grow and reproduce in the water phase, primarily at the fuel/water... 

In the last twenty years, there was been a shift in the prevalent population of microorganisms found in contaminated fuel systems from the mold Hormoconis resinae to bacteria such as Pseudomonas species, Alcaligenes species... 

Figure 5 Hormoconis resinae (formerly Cladosporium resinae), growing at the interface between the darker diesel fuel phase at the top and the lighter water phase on the bottom, produces a thick grey to black microbial biomass.

FuelSTAT resinae was developed by Conidia Bioscience, Ltd. for the rapid (10 min) identification of Hormoconis resinae in aviation fuel. This is a semi-quantitative immunoassay test that will determine if the level of H. resinae contamination is below the level of significant contamination, per the lATA Microbial Contamination Task Force recommendations. This test has the sensitivity to determine the presence of 1,000 pg of H. resinae biomass in 1 liter of fuel or 1 ml of water. Test results of negative, low positive or high positive correlate to < 1000, 1,000 to 10,000 or > 10,000 pg of the fungus in either 1 liter of fuel or 1 ml of water respectively. The manufacturer of this test kit suggests that an aviation fuel system be monitored at least once a year. However, if the aircraft travels in warm, tropical areas it is advisable to monitor once a month. If the test indicates a low positive contamination, some action may be needed and monitoring should be done more often. With a high positive test result, immediate remedial action is required (Conidia Bioscience Ltd, 2002). 

Scanning electron microscopy can identify microorganisms by shape and size. Fungi, such as Hormoconis resinae, will appear as interwoven, filamentous structures with branching approximately 2 pm in diameter (Westbrook et al, 1988). Yeast will be oval-shaped, some with budding, 1-2 pm in diameter. Bacterial rods, such as Pseudomonas sp., will be 0.5-1 pm wide and 2-3 pm long. Some bacteria form long chains of cells or filaments. 

This is a rapid (detection within four hours) and sensitive method to identify microbial contaminants. However, you must have the appropriate equipment and trained personnel to run the test and interpret the test results. Immunofluorescence was evaluated by Gaylarde et al. (1998) as a method for identifying Hormoconis resinae in aviation kerosene fuel. There was little cross-reaction with other fuel fungi. The hyphae and spores of Hormoconis resinae were detected in a biofilm. 

Cladosporium resinae (sny. Hormoconis resinae, tel., Amorphotheca resinae)... 

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