Isolation and Characterization of Fungi from Termite Mounds in Taita Taveta County, Kenya

Abstract

Mounds of the fungus-cultivating termites from Taita Taveta Countyare multi-cultural ecosystem that host diverse microorganisms including fungi.The county is a tropical savannahregion which is known to harbordestructivefungus-cultivating termites. Fungi of the genus Termitomyces are the only fungal species that have been reported to colonize termite mounds. However, there are also other filamentous fungi that inactively colonize termite mounds and only sporulate when favorable conditions are provided.Theaimof the current study was to isolate and characterizefungalspecies from termite mounds in Taita Taveta County. Twenty two fungalcultureswere isolated from 20 termite mounds.Identified fungal nodules were inoculatedonto culture medium (PDA) and incubated at 27oC.Sporulating cultures were monitored and sub-cultured till axenic. The functions and viability of the cultures were confirmed on Malt Extract Agar (MEA). Thirteen fungalspecies were characterised using universal fungal primers that amplified the internal transcribed spacers (ITS) of the fungal ribosomal DNA. The ITS sequence data were congruent to 11 morphological features.Physiological and morphological features of the pure cultures were equally significant and congruent.Qualitative enzymatic assays of isolates (6, 10, 11), exhibited enzymatic activities on carbon substrates. Based on the principle of the best hits of ITS sequences,three isolates (6, 10, 11) were Termitomyces species, two isolates (1 and 16) wereAspergillus species, isolates 3, 13, 14, 15, 19, 22 were Arthrinium, Fusarium, Pestalotiopsis, Solanum, Penicillium, and Aueobasidiumspecies respectively.Termite mounds are rich in fungal species in addition to the known Termitomyces. Isolates 2 and 3 were isolated from the same mound, but had different features. Isolates 21 and 22 were also isolated from the same mound and they had totally different features. Phylogenetic analysis classified isolate 21 as an independent cluster while isolate 22 as a relative to genus Aureobasidium. The occurrence of the fungal isolates was not specific to a given geographical condition and the mound. Each of the mounds had different fungal isolates. Though, morphological characteristics were shared among the 22 isolates, their diversity was confirmed by the genetic differences based on the sequencedITS data. There is need to explore such microorganisms for biotechnologicalapplications such as enzymatic assaysand antibiotic production.