Purpose: To determine the effect of the secondary metabolites from
Penicillium
sp. H9318 on
cytotoxicity and cell cycle progression.
Methods: A yeast PP1 inhibitory screening system was carried out to confirm the presence of anti-
PP1c activity in crude acetone extracts of strain H9318. The extracts were fractionated and identified as
Fraction S1 and Citrinin 9318 (CTN9318). Various cancer cell lines were used to test for the toxicity of
the crude acetone extracts, Fraction S1 and Citrinin 9318, using MTT viability assay.
Results: It was found that a colorectal cancer cell line, HT-29, was susceptible to Fraction S1 and
Citrinin 9318. A propidium iodide (PI)-incorporated DNA assay was used to show that there was G2/M
arrest in HT-29 by Citrinin 9318.
Conclusion: Citrinin 9318 inhibits the viability of HT-29 via mitotic block. The results suggest that
Citrinin 9318 is capable of exerting cytotoxicity and mitotic arrest in a colon cancer cell line, HT29
