The present invention relates extracts from physiologically stressed Arthrospira having anti-inflammatory activity and/or the ability to stimulate growth of new cells, compositions comprising the extracts having anti-inflammatory activity and/or the ability to stimulate growth of new cells, and use of such compositions in the treatment of diseases or conditions having an inflammatory basis and/or in the treatment of diseases or conditions of skin, wherein the diseases or conditions of skin are not the result of a microbial infection or infestation.