Abstract:

The antioxidant activity and immune activity of small peptides (tripeptides and tetrapeptides) from fermented
sesame meal were investigated in vivo. Totally 56 healthy Kunming mice (4 weeks old) were randomly divided into 7
groups. The mice in normal control group were administered with saline, and those in test groups were administered
with sesame tripeptides or tetrapeptides at doses of 2, 4, and 8 mg/d, respectively. After continuous intragastric admi
nistration for 28 days, the mice were sacrificed to harvest serum and liver. The organ coefficients of liver, spleen and
thymus, malondialdehyde (MDA) content in serum and liver, and the activities of superoxide dismutase (SOD) and
glutathione peroxidase (GSH-Px) in liver were determined. T-lymphocytes such as CD3＋, CD4＋ and CD8＋ in spleen
were tested by flow cytometer. The results showed that, in mice fed the sesame peptides, the organ coefficients were not
changed significantly (P ＞ 0.05), but MDA contents in serum and liver were reduced significantly (P ＜ 0.05). SOD and
GSH-Px activities in liver exhibited a significant increase. CD4＋/CD8＋ ratio was also significantly increased (P ＜ 0.05) in
the tetrapeptide high-dose group. Therefore, both tripeptides and tetrapeptides from fermented sesame meal have obvious
antioxidant capacity in vivo, and the tetrapeptides can enhance the body’s immune activity when administered at high dose.

Key words: fermented sesame meal, peptide, antioxidant activity, immune activity, animal experiments