Figure 5From: Measurement of microbial activity in soil by colorimetric observation of in situ dye reduction: an approach to detection of extraterrestrial lifeReduction of XTT by the heat-treated control soil and the life-positive Lake Boney Basin, Antarctica soil Data points represent: (▼), Live Boney Basin Soil; (■), Killed Boney Basin Soil; (●), Negative Control (no soil); Lake Boney Basin soil only very slowly reduced DCIP (data not shown). Data points are means of three replicates, +/- one standard deviation. Dye-only controls showed no reduction over the time course of the experiment. AU = Absorbance UnitsBack to article page