Low-molecular weight keratins with anti-skin aging activity produced by anaerobic digestion of poultry feathers with Fervidobacterium islandicum AW-1.

Bioactive peptides contribute to various cellular processes including improved skin physiology. Hence, bioactive keratins have attracted considerable attention as active cosmetic ingredients for skin health. Here, we obtained low molecular weight (LMW) keratins from native chicken feathers by anaerobic digestion with an extremely thermophilic bacterium Fervidobacterium islandicum AW-1, followed by stepwise fractionation through ultrafiltration. To assess the effects of the feather keratins on skin health, we performed in vitro and ex vivo assays to investigate their inhibitory effects on matrix metalloproteinases (MMPs). As results, LMW feather keratins marginally inhibited collagenase, elastase, and radical scavenging activities. On the other hand, LMW feather keratins significantly suppressed the expression of ultraviolet B (UVB)-induced MMP-1 and MMP-13 in human dermal fibroblasts. Furthermore, phospho-kinase antibody array revealed that LMW feather keratins suppressed UVB-induced phosphorylation of Akts, c-Jun N-terminal kinases 1, p38 beta, and RSK2, but not ERKs in human dermal fibroblast. Overall, these results suggest that LMW feather keratins are potential candidates as cosmeceutical peptides for anti-skin aging.