Does source of tryptone in growth medium affect oxidative stress resistance in Escherichia coli?
Depending on the source of tryptone, bacteria may experience different levels of oxidative stress in tryptone-containing nonselective growth media. Although these levels of oxidative stress are subinhibitory, they may trigger a stress response that makes the bacteria more resistant to a subsequent exposure to a lethal or inhibitory level of oxidative stress.
In contrast to other investigations, there was no significant short-term effect of calcium supplementation on biochemical markers of either bone resorption or formation.