“…Cathepsin D plays an important role during meat processing, which may finally influence meat tenderness and quality traits (Cafe et al, 2010;Godiksen et al, 2009). A number of myofibrillar proteins, such as titin and connectin, were found to be susceptible to hydrolysis by cathepsin D.It is essential for proteolysis of proteins to help in regulating cell growth and tissue homeostasis, which is expressed in most cells and over-expressed in breast cancer cells (Masson et al, 2011;Srivastava et al, 2006;Tandon et al, 1990), even involved in tumor metastasis (Ollinger, 2000;Lah et al, 1996;Rochefort et al, 1996). Nowadays, protease inhibitors have been traditionally developed from natural product screening for lead molecules with subsequent optimization (Chaturvedi et al, 2013), thus, chitosan-based cathepsin D inhibitor is a potential.…”