[Pharmacological studies on small peptide fraction derived from soybean. The effects of small peptide fraction derived from soybean on fatigue, obesity and glycemia in mice].

The present research was an attempt to determine the pharmacological actions as for anti-fatigue, anti-obesity and hypoglycemia of small peptide isolated from soybean in mice. Small peptide administration prevented the decrease in sporting movement induced by concussion stress for 3 h in mice. In addition, it should be noted that the recovery rate of fatigue in 60 min after small peptide administration was over one hundred percentage in comparison with that after pretreatment, while the equivalent dose administration of amino acid mixture with the same small peptide amino acid composition did not prevent the decrease in sporting movement. In gold-thioglucose (500 mg/kg (i.p.))-induced obese mouse body weight gain, liver weight and body lipid level around uterine were significantly reduced by the chronic oral administration of small peptide (200, 1000 mg/kg). Administration in 1000 mg per kg of small peptide significantly lowered hyperglycemia in 30 and 120 min after glucose (3 g/kg (p.o.)) administration, whereas the equivalent amino acid mixture showed no effect. In conclusion, it suggested that small peptide isolated from soybean might have some pharmacological effects of anti-fatigue, anti-obesity, and hypoglycemia.