TABLE 3.

Effects of exposing functionally stained human lung epithelial carcinoma A549 cells to T. harzianum strain ES39 and different concentrations of alamethicin

Substance tested and concn	Observed effect
	Δψm detected with JC-1b	% Uptake of propidium iodide by calcein-AM- stained cellsc
Alamethicin
5 μg ml−1	100% Dissipated	<10
50 μg ml−1	100% Dissipated	100
T. harzianum strain ES39,a ∼20 μg ml−1	100% Dissipated	<10
Methanol (negative control), 3.3%	100% Preserved	<10

^aHPLC-purified fraction 3 (containing peptaibol components IV and V) from T. harzianum strain ES39 was used.

^bStaining with JC-1 (5,5′,6,6′-tetrachloro-1,1′,3,3′-tetraethylbenzimidazolo carbocyanine iodide) visualizes the membrane potential of mitochondria (Δψ_m). Preserved Δψ_m is visible as orange fluorescence, and the dissipation of mitochondrial membrane potential changes the fluorescence to green.

^cDual staining with calcein-AM and propidium iodide stains the cells green unless the membrane damage allows the uptake of propidium iodide. Green fluorescence indicates no damage, and red fluorescence is due to uptake of propidium iodide.