mettle.
uh not this? So you mean like micro nutrients?
mettle
[ˈmedl]
NOUN
a person's ability to cope well with difficulties or to face a demanding situation in a spirited and resilient way.
"the team showed their true mettle in the second half"
synonyms:
spirit · fortitude · tenacity · strength of character · moral fiber · steel · determination · resolve · resolution · steadfastness · indomitability · backbone · hardihood · pluck · nerve · gameness · courage · courageousness · bravery · gallantry · valor · intrepidity · [more]