As nouns the difference between nutrient and chemosymbiosis

is that nutrient is a source of nourishment, such as food, that can be metabolized by an organism to give energy and build tissue while chemosymbiosis is (biology) a form of symbiosis in which a bacterium provides chemically-derived energy and nutrients, often via the oxidation of hydrogen sulfide, to a higher organism.

As an adjective nutrient

is providing nourishment.