Fungal infestation of termite mounds in Kopong, Botswana and their effects in mice red blood cells

Abstract

This paper aims to determine the fungal infestation, pH and moisture contents of termite mound soil from five locations in Kopong, Botswana and in vitro, effect of fungal extracts of species recovered from termite mound on hemolysis in rats’ red blood cells. The moisture contents of the five termite mounds ranged from 20.5 to 37.9% whereas pH ranged from 7.8 to 8.07. The CFU/g of termite mound soil varied from 3.0 x 10³ to 1.9 x 10⁴. No correlation could be established among moisture contents, pH and the fungal count. The termite mounds contained species belonging to three genera, Aspergillus, Penicillium and Fusarium. Aspergillus species were found to be the most frequent and recovered from almost all soil samples. The fungal species recovered from soil samples of five termite mounds include; Aspergillus niger, A. fumigatus, A. candidus, A. ochraceus, A. niveus, A. flavus, A. parasiticus, A. terreus, Penicillium sclerotiorum, P. thomii, P. digitatum and Fusarium culmorum. Out of twelve species, fungal extracts of seven species were assayed for hemolysis of mice red blood cells, and all of them caused red blood cell hemolysis (92.7% to 96.5% hemolysis with 2 ml of fungal extract). The highest percentage hemolysis was obtained for P. digitatum (97.5%). There was no significant difference in percentage hemolysis between fungal isolates at p>0.05 but differed significantly with different volumes of fungal filtrate. The percentage hemolysis increased with the increase in fungal titrate volume for all fungal isolates except for A. ochraceus and P. sclerotiorum. Thus, geophagy of termite mounds may result in hemolysis by fungal toxins contained in them.