Bagassois III. Isolation of Thermophilic and Mesophilic Actinomycetes and Fungi from Moldy Bagasse ∗

Summary and Conclusion

Industrial workers who grind raw sugar cane fiber from which the sucrose content has been extracted and which has been stored in bales under high environmental temperature develop a characteristic respiratory illness called bagassosis. Precipitins against unknown antigens in crude bagasse have been detected in the sera of many patients with this disorder, and thermophilic microorganisms are suspected as likely sources of bagasse antigen. This report describes the most common thermophilic actinomycetes and fungi isolated from the “bagasse” fiber. These include M. vulgaris, S. thermoviolaceus, S. griseoflavus, S. fradiae, S. thermovulgaris, S. olivaceus, and H. lanuginosa. The sera of many patients with bagassosis contained precipitins against cellular extracts of M. vulgaris. Since bagassosis results almost exclusively from inhalation of dried stored sugar cane fiber and M. vulgaris has been the most common isolate from this type of bagasse, it is postulated that M. vulgaris is the main source of “moldy bagasse” antigens.