Spermicidal and antioxidant potency of Solanum macrocarpon L. (African eggplant) leaf ethanol extract in albino rats

Oxidative processes give rise to reactive oxygen species/oxidants which are detrimental to living cells and underlie many pathologic conditions. On the other hand, many plant species possess antioxidant properties and phytochemicals which are closely linked to their therapeutic potentials. Solanum macrocarpon is a tropical plant which is traditionally claimed to possess therapeutic properties. Although, antioxidant potentials have been reported for different Solanum species and antioxidants have been reported to improve sperm morphology and motility; this has not been fully elucidated in S. macrocarpon. Following a comparative phytochemical and in vitro antioxidant screening of S. macrocarpon fruit, leaf and root ethanol extracts, this study evaluated the effect of S. macrocarpon leaf ethanol extract (SMLE) on sperm parameters in vitro and antioxidant enzymes in vivo. The effect of SMLE on sperm motility and vitality was examined in vitro at concentrations of 2.5, 5 and 10 mg/ml at 1, 5 and 10 min’ intervals. Furthermore, thirty male albino rats (10–12 weeks old), separated at random into six groups (A–F, n = 5), and administered SMLE for 42 days, were used to investigate the antioxidant potency (AP) of SMLE in vivo. The phytochemical screening of different parts of S. macrocarpon revealed that SMLE had the highest (p < 0.05) composition (mg/100 g) of tannins, flavonoids, steroids, terpenoids and saponin compared to fruit and root extracts. Furthermore, SMLE had the highest (p < 0.05) DPPH-scavenging antioxidant potency, which was similar to that of the control (ascorbic acid) at 200 µg/ml concentration, compared to the fruit and root extracts. SMLE significantly (p < 0.05) exhibited spermicidal potency in vitro in terms of reduced sperm motility and vitality but showed no significant effect on lipid peroxidation/antioxidant enzymes in vivo. The findings suggest that the SMLE possesses in vitro spermicidal potential despite its potent antioxidant activity.