Tighten is the opposite of Loose. Loose is a synonym of Separate. 
you are likely to find Sugar in/at/on Jar. Sugar is related to Agent. Agent is related to Seed. 
Tighten <--Antonym--> Loose <--Synonym--> Separate 
Jar <--AtLocation-- Sugar <--RelatedTo--> Agent <--RelatedTo--> Seed 