Effect of carob (Ceratonia Siliqua) kibble extract on the kinematic parameters of human frozen-thawed sperm: A preliminary study

Semen quality and related parameters correlate directly with fertilization, consequently assisting reproductive technology outcomes. Traditional studies on carob (Ceratonia siliqua) have demonstrated its effect on male fertility potential via the reductive effect on reactive oxygen species. This study aimed to investigate the effect of carob kibble extract on sperm motility.

The extract was made using acetone as a solvent, followed by vacuum evaporation and filtration. Following thawing, each of the forty human semen samples was divided into four groups and exposed to concentrations of 0.0 (control), 0.05, 0.2, and 0.8 mg/ml of the extract. Percentages of progressive motile, non-progressive motile, and immotile sperms, as well as other kinematic parameters, were assessed by computer-aided sperm analysis immediately after exposure to the concentrations (T0) and one hour later (T1). Data were analyzed by repeated measure analysis of variance and paired sample t-student tests using SPSS software. The level of p< 0.05 was considered statistically significant.

No significant difference was found between groups at T0 or T1 values. However, a comparison of matched doses at T0 and T1 indicated that lower doses 0.05 and 0.2 mg/ml could significantly (p<0.05) inhibit natural decline in motility.

Adding lower doses of carob kibble extract on a thawing medium could have a supportive effect on sperm motility. However, adding the extract to a vitrification solution before a freezing process, as well as oral intake of the extract seems to have more efficiency than would be a subject for further studies.