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Indian Journal of Medical Microbiology, Vol. 23, No. 2, April-June, 2005, pp. 144-145 Letter To Editor Prevalence of Non-Keratinophilic Fungi in the Soil Kumari G.R., Mahrora S., Rao P.S. Department of Microbiology, KMC, Manipal Correspondence Address:Department of Microbiology, KMC, Manipal - 576 219, Karnataka, psraos82@yahoo.co.in Code Number: mb05042 Dear Editor, Majority of the fungi producing diseases in man and animals exist freely in nature as soil saprophytes or plant pathogens and gain entrance into the body through abrasion, implantation or inhalation. Adametz isolated fungi for the first time from the soil in the year 1886, since then there has been very few reports.[1]-[3] Manipal and surrounding places being coastal areas, experience heavy rainfall with high atmospheric humidity which is most suitable for fungal growth. Soil with natural bamboo habitat in nearby Western ghats with rat burrows predisposes the fungal growth in the area. Soil samples collected in sterile paper envelops from 40 different areas surrounding Manipal in the month of October (post monsoon) were investigated for the presence of fungi as per the standard protocol described earlier.[2] Soil samples were obtained from sites of rat burrows at the bottom of bamboo trees, which is natural habitat around the place and commonly seen surrounding Manipal. About 10 grams of each sample of soil was transferred to a sterile tube containing 15-20 mL of sterile saline. The suspension was shaken vigorously and allowed to stand for 30 minutes. One mL of the clean supernatant fluid was inoculated into two tubes of Sabouraud broth and for the isolation of Nocardia spp. by paraffin bait technique.[2] Another 5 mL of the supernatant fluid was transferred to a sterile tube containing 5 mL of sterile saline with antibiotics (500 units of penicillin and 30 mg of streptomycin/mL), shaken well and allowed to stand for two hours in order to reduce the bacterial flora. A portion of the suspension was inoculated on Sabouraud dextrose agar with and without chloramphenicol (0.05 mg/mL) and cycloheximide (0.5 mg/mL) and incubated at 26°C and 37°C respectively. The cultures were examined twice weekly for a period of six weeks. The different types of colonies were subcultured on Sabouraud dextrose agar slants and pure cultures of the isolates were identified on the basis of microscopic morphology and cultural characteristics. Out of 40 soil samples analysed for the presence of fungi, 46 strains of fungi were isolated. Among the 46 strains of fungi isolated, 18 strains were Cunninghamella followed by Fusarium (13), Aspergillus (7), Rhizopus (4), Penicillium (2) and Paecilomyces (2) spp. Of the various fungi isolated from the different soil samples the prevalence of Cunninghamella spp. was shown to be more in the present study. The next common genus in our study were Fusarium and Aspergillus spp. Aspergillus spp. was the commonest fungus isolated by other workers. Studies elsewhere reported Geotrichum and Fusarium spp. as common in the soil sample.[3] Yet another study reported. Penicillium as the second dominant spp. Other workers have reported Acremonium and Pseudallescheria boydii also in their studies from soil samples from Tamilnadu,[4] Delhi, UP, Nepal, Andaman and Nicobar islands which we have not isolated.[3] The causative agents of Mycetoma[4] and Systemic mycoses, as reported by others workers, were not encountered in our study. References
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