Abstract
Black tea is consumed worldwide and is believed to play a role in cancer prevention. Xerophilic aflatoxigenic fungi are highly hazardous contaminants of tea since they are associated with tea quality impairment and human health risk. The present study reports isolation of such xerophilic and aflatoxigenic fungi associated with marketed tea. Twenty different tea samples collected from the local markets of Tamilnadu, India were investigated for fungal contamination. The results indicated contamination by 0.38%
Aspergillus flavus
. Other common contaminant fungi including
Penicillium
spp. (0.30%),
Pacelomyces
spp. (0.14%), and
Mucor
spp. (0.19%) were also isolated. Amongst the fungi isolated
Aspergillus niger
ML01 and
A. flavus
ML02 were found to be xerophilic aflatoxigenic mycoflora. Phylogenetic analysis based on 28S rRNA revealed their close ancestry. The chloroform and acetone extracts of spices
Elettaria cardamomum
and
Syzygium aromaticum
exhibited antifungal inhibitory activity on growth and toxin elaboration of both these xerophilic tea contaminants
A. niger
ML01 and
A. flavus
ML02. The results advocate the use of these spices plant or their extracts as novel antimicrobials which may add preservation and flavour in marketed tea.