The proteolytic activity of ginger rhizome was studied with bovine serum albumin (BSA), collagen and actomyosin as substrates. A semipurified, powdered enzyme preparation was prepared by buffer extraction of an acetone powder of ginger rhizome and subsequent acetone precipitation of the proteolytic principle from the buffer extract. With 3 BSA as substrate, a relatively high proteolytic activity occurred over a pH range of 4.5–6.0, with an optimum pH of 5.0. The optimum temperature for proteolysis of BSA was 60°C during a 10 min reaction time, with rapid denaturation of the enzyme occurring at 70° C. NaCl in cone up to 10 produced about a 20 and 50 reduction in proteolysis of collagen and BSA, respectively. The ginger protease was protected by dithiothreitol during extraction and reaction, indicating the involvement of −SH groups at the active site. The analyses of soluble peptide amino acids or terminal amino acids suggest that the proteolysis of collagen is many fold greater than that of actomyosin. The combined proteolysis of these two muscle protein fractions by the ginger protease resulted in significantly more tender meat. According to conventional nomenclature, “Zingibain” is the proper name for this proteolytically active principle inZingiber officinale roscoeor ginger rhizome which is commonly referred to as gingerroot. For meat applications, a possible advantage of zingibain over papain and ficin is the greater proteolysis of collagen in comparison to actomyosin. When compared to reported values for bromelain, zingibain has a higher optimum activity temperature, which is desirable in some ap
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