Microbiological analysis of Argonne premium coal samples

The microbial content of different lots of three Argonne Premium Coals (North Dakota Beulah Zap lignite Wyodak subbituminous, and Illinois No. 6 bituminous) was analyzed using 28 kinds of growth medium incubated under aerobic, microaerobic, and anaerobic conditions. This work was initiated for the purpose of isolating microorganisms that naturally occur in coal, with the presumption that they would be valuable for coal bioconversion technology. The type of microorganisms that were targeted for cultivation included aerobes, microaerophiles, facultative and strict anaerobes, fungi, sulphate-reducing bacteria,methanogenic bacteria, and chemoheterotrophs. Media included nutrient agar and broth, yeast/ mold agar and broth, lactate medium, Bacto anaerobic agar, triple sugar iron agar, selenite broth, Eugon broth, brewer modified thioglycollate medium, thioglycollate medium without dextrose, and 11 different methanogen enrichment media containing various primary carbon sources. After a lengthy incubation period,growth was determined by turbidity and/or production of methane. Results indicated that no viable microorganisms were derived from the coal samples.