fetch publication-keywords via API/OAI/FTP from open Access journals

Question

[asmi]

Hi all,

Is there a known API or any method to fetch the "author listed keywords" for all publications in DOAJ.org or PMC open access subset?

I tried the ftp of PMC open access subset but the XML files only have IDs, abstract, title, author and affiliations as the metadata to any article. I am looking to mass fetch the keywords too listed with each publication.

Also, I saw few threads around the same but still haven't found the answer I was looking for. So have made a new post.

Any help is much much appreciated.

Thanks,
Asmi