Silkworm silk consists of two main proteins which are silk fibroin and silk sericin. Silk fibroin, the
fiber protein structure, is widely used in biomaterial applications particularly as sutures for decades
because it has appropriate mechanical properties and slow degradability [1]. Silk sericin, the gluelike
proteins which covering silk fibroin fibers to form silk cocoons, is commonly used as
ingredient in various products such as cosmetics, nutrition supplements and wound healing products
due to its ability to enhance cell attachment and proliferation [2]. It was reported that sericin
promoted collagen production in wound healing process [3]. However, there are many works
reported on the adverse effects of silk sericin such as immunologic stimulation and toxicity [4,5].
Therefore, in this study, it was interesting to clarify the cytoxicity of silk sericin in terms of
attachment and proliferation of L929 mouse fibroblast cells. This study was divided into 2 parts.
Part 1 was the investigation on the effect of sericin concentration on cell viability in the system of
silk fibroin/sericin films using 2 types of silk fibroin, Bombyx mori Nangnoi Srisaket 1 and Bombyx
mori Jul 1/1. The effect of extraction method including heat, acid, alkali and urea treatments on