May be,

You can use the DPPH method to evaluate the possible antioxidant activity.

Dear Nwonuma,

It is an interesting subject. Answer of your question is in generally positive.

There are published papers and reports about antioxidant activity in shell of animal origin.

Antioxidant in shell of abalona:

http://www.ncbi.nlm.nih.gov/pubmed/25062421

Antioxidant in shrimp shell:

http://www.ncbi.nlm.nih.gov/pubmed/24950313

Antioxidant in sea urchin shell:

http://www.idosi.org/aejsr/6(3)11/10.pdf

Even antioxidant in shrimp shell waste:

http://pubs.acs.org/doi/abs/10.1021/jf950597f

Methodologically, total antioxidant capacity ( TAC) determination is simple and many companies produce reliable  TAC kits. 

best

mehdi

I think antioxidant activity is ubiquitous in nature in all living beings as a protection mechanism. The total activity however may differ in different organisms. There are several methods to determine the activity, DPPH being the most popular.

There are several threads on the subject of antioxidant activity in RG with very informative and interesting posts. You may follow them for more information.

many compounds have antioxidant potential which can be explored using several protocols.u can hv a look at me papers for the same. Luk