Table 2

Effect of administration of aqueous extract of burdock roots for 15 days on serum testosterone concentrations

Parameter

Mean frequency ± S.E.M

Control

Burdock extract 300 mg/kg

Burdock extract 600 mg/kg

Burdock extract 1,200 mg/kg

Viagra (60 mg/kg)

Testosterone

2.3 ± 0.4

3.2 ± 0.5

4.3 ± 0.5*

5.2 ± 0.5**

2.9 ± 0.6

S.E.M.: mean standard error. n = 6 (number of animals in each group), significant difference from control, significance level: *p < 0.05, **p < 0.01

JianFeng et al. BMC Complementary and Alternative Medicine 2012 12:8   doi:10.1186/1472-6882-12-8