Mammalian fertilization is a complex cascade process consisting of sperm migration through the female reproductive tract, physiological changes to sperm such as sperm capacitation and acrosome reaction, and sperm-egg interaction in the oviduct in vivo. On the other hand, in vitro fertilization (IVF) is a process by which egg cells are fertilized by sperm outside the body: in vitro. IVF has been used for a variety of purposes in reproductive biotechnology for human and animals. The discovery of sperm capacitation in 1951 promoted the development of IVF technology. In the initial stage of IVF, sperm capacitation in preincubation medium was shown to be essential to fuse with eggs. Besides, sperms should detour some of the in vivo regulations for IVF. This review introduces a general mammalian fertilization process, including sperm capacitation, removal of cumulus matrix, acrosome reaction, and sperm-egg fusion and focuses on the roles of key biochemical molecules, signal mechanisms, and genes involved during IVF and novel results of sperm-oocyte interaction elucidated in various gene-knockout mice models.

The potential antioxidant activities of different fractions from Prunella vulgaris var. lilacina were assayed in vitro. Among several fractions, n-BuOH fraction showed the highest 1,1-di[henyl-2-picrylhydrazyl (DPPH) free radical scavenging (IC50=0.50μg/mL). The results of 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical scavenging activity and ferric reducing antioxidant power (FRAP) assay showed the concentration dependency and n-BuOH fraction appeared a better result than the other fractions at the same concentrati on in this study. Moreover the total phenol and flavonoid contents of n-BuOH fraction contained the highest level. Additionally, correlation analysis indicated a high correlation between the antiradical activity and the total phenolic and flavonoid contents (p 〈 0.001). It suggests that n-BuOH fraction obtained from the 70% EtOH crude extract of Prunella vulgaris var. lilacina has wide potential for use as a source of antioxidant material.