Difucol is a phlorotannin found in the brown algae ''

Analipus japonicus ''Analipus japonicus'', or sea fir, is a brown alga species in the genus ''Analipus''. This species contains the phlorotannins difucol, trifucol, tetrafucol A and B, two pentafucols, four hexafucols, a heptafucol mixture and halogenated co ...

'' and ''

Cystophora retroflexa ''Cystophora retroflexa'' is a brown alga species in the genus '' Cystophora.'' It found is found off the coasts of New Zealand and Australia. It is the type species of the genus. Prefers more sheltered environments compared to other ''Cystophor ...

''.

References

Phlorotannin dimers {{aromatic-stub