17476
Water and ethanolic extracts of 16 species of seaweeds collected along the Danish coasts were screened for antioxidant activities using four in vitro antioxidant assays ( 2 , 2 - diphenyl - 1 - picrylhydrazyl radical scavenging activity , reducing power , ferrous ion - chelating and liposome model system ) .
 Chemical: 2 , 2 - diphenyl - 1 - picrylhydrazyl; Chemical: ferrous
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
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Answer:
 Chemical: 2 , 2 - diphenyl - 1 - picrylhydrazyl; Chemical: ferrous