TABLE 2.

Viability of dormant and superdormant spores on various media with and without heat activation^a

Bacillus species and plating medium	Spore viability (%)b
	No heat activation		Heat activation
	D	SD	D	SD
B. cereus and LB	40	1	100	3
B. cereus and LB + alanine/inosine	88	110	102	98
B. megaterium and LB	87	4	100	5
B. megaterium and LB + glucose/proline	107	100	100	108
B. subtilis and LB	87	1.5	100	10
B. subtilis and LB + AGFK/valine	105	95	100	96

^aDormant (D) and superdormant (SD) spores at an OD₆₀₀ of 1 were heat activated at the temperature optima for dormant spores, cooled, and applied to LB medium plates without or with the mixture of the original and alternate germinants; the plates were incubated at 30°C (B. megaterium) or 37°C (B. cereus and B. subtilis) for 24 to 36 h; and colonies were counted.

^bSpore viability is expressed relative to that of heat-activated dormant spores of the same species on LB medium plates, and this latter value was set at 100%.