Characteristics of protein from red crab (Chionoecetes japonicus) shell by commercial proteases

This study was performed to examine the characteristics of protein of red crab (Chionoecetes japonicus) shell powder hydrolyzed by commercial proteases. Red crab shell was digested by commercial proteases, such as Protamex (P), Neutrase (N), Flavourzyme (F), Alcalase (A), Protease M (PM) and Protease A (PA). Protein yield analyzed by Biuret assay, absorbance at 280 nm and brix revealed that PA was the enzyme having the highest proteolytic activity. SDS PAGE showed that molecular weight of proteins produced by protease treatments was various and below 150 kDa. Combinational treatment of proteases (PA + P, PA + PM, PA + F, PA + A) was tried whether these increase protein hydrolysis from red crab shell powder compared to a PA single treatment. Soluble protein content was similar, but amino acid concentration by combinational treatments was higher than PA single treatment [PA + P 247.4 mg/g > PA + F (206.4 mg/g) > PA + A (133.4 mg/g) > PA + PM (59.1 mg/g) > PA (54.9 mg/g)]. Amino acid composition by combinational treatments was slightly different. Most abundant essential amino acids were phenylalanine, glycine, alanine, and leucine, whereas tyrosine and cystine were not detected.

Hypolipidemic effect of Salicornia herbacea in animal model of type 2 diabetes mellitus

To control blood glucose level as close to normal is a major goal of treatment of diabetes mellitus. Hyperglycemia and hyperlipidemia are the major risk factors for cardiovascular complications, the major cause of immature death among the patients with type 2 diabetes. The purpose of this study is to determine the hypoglycemic and hypolipidemic effects of Salicornia herbacea in animal model of type 2 diabetes and to investigate the possible mechanisms for the beneficial effects of S. herbacea. S. herbacea was extracted with 70% ethanol and desalted with 100% ethanol. Three week-old db/db mice (C57BL/KsJ, n=16) were fed AIN-93G semipurified diet or diet containing 1% desalted ethanol extract of S. herbacea for 6 weeks after 1 week of adaptation. Fasting plasma glucose, triglyceride, and total cholesterol were measured by enzymatic methods and blood glycated hemoglobin (HbA1C) by the chromatographic method. Body weight and food intake of S. herbacea group were not significantly different from those of the control group. Fasting plasma glucose and blood glycated hemoglobin levels tended to be lowered by S. herbacea treatment. Consumption of S. herbacea extract significantly decreased plasma triglyceride and cholesterol levels (p<0.05). The inhibition of S. herbacea extract against yeast alpha-glucosidase was 31.9% of that of acarbose at the concentration of 0.5 mg/mL in vitro. The inhibitory activity of ethanol extract of S. herbacea against porcine pancreatic lipase was 59.0% of that of orlistat at the concentration of 0.25 mg/mL in vitro. Thus, these results suggest that S. herbacea could be effective in controlling hyperlipidemia by inhibition of pancreatic lipase in animal model of type 2 diabetes.