During the siege of Leningrad, a group of Russian botanists from the Institute of Plant Industry locked themselves into a secret vault and starved to death rather than consume the large collection of seeds which they were guarding in case of an apocalypse. – WTF Fun Facts
Source: https://www.rbth.com/blogs/2014/05/12/the_men_who_starved_to_death_to_save_the_worlds_seeds_35135