The Potential of Jatropha variegata Fruits as a Natural Contraceptive: Antifertility Activity and Phytochemical Analysis

Abstract

Background: Jatropha variegata (family, Euphorbiaceae) is native to Yemen, where it is commonly known as the Ebki shrub. The fruits of the plant are traditionally ingested by local women as a natural method of contraception. This study was undertaken to investigate the phytochemical content of the methanol extract of J. variegata fruits and to evaluate its antifertility potential.

Methods: Isolation of the chemical constituents was performed by chromatographic techniques, and the chemical structures of these compounds were identified by spectroscopy. The antifertility activity of the methanol extract was assessed in two experimental rat models to explore both the anti-implantation and the estrogenic/antiestrogenic activities in females. In these models, the number of successful implants, the size of litter, and body/ovary weights were all recorded. The development of ovarian follicles was also monitored via histological staining.

Results: Phytochemical work on the fruit extract of J. variegata led to the isolation of two oils (JF1 and JF2) and methyl elaidate. GC-MS analysis of the JF1 oil revealed that the major chemical constituents were fatty acid esters (43.77%), hydrocarbon alkanes (20.65%), and terpenoids (4.65%), while terpenoids (28.8%), fatty acids and their esters, (29.47%), and phytosterol (10.49%) were the major components found in the JF2 oil. The methanol extract of J. variegata fruit exhibited 50% and 93% abortifacient activity at 150 and 300 mg/kg doses, respectively. The extract also showed significant estrogenic activity as evidenced by the increase in rat ovary weight at a dose of 300 mg/kg compared to the control group. Histological analyses further confirmed this estrogenic activity.

Conclusions: J. variegata fruits possess an antifertility activity that appeared to result from its antiembryo implantation potential and from its estrogenic activity. The bioactive constituents involved in these activities may need to be further explored and exploited in the pursuit of newer contraceptives.

Figure 1

Chemical structure of methyl elaidate.

Figure 2

Histopathological studies on rat ovaries. (a) Ovary from negative control group: primary follicle (PF), antral follicles (AnF), Graafian follicle (GF), oocyte (O), corona radiata (red arrow), zona granulose (ZG), basement membrane (green arrow), theca externa (yellow arrow), theca interna (blue arrow), cumulus oophorous (CO), and interstitial tissue (IT). (b) Ovary from rats treated with estradiol valerate: vacuolated oocytes (arrow), atretic follicles (AF), and corpus luteum (CL). (c) Ovary from rats treated with plant extract (300 mg/kg): shrinkage and shift of ooplasm to one side (green arrow), absence of nucleus and zona pellucida (red arrow), cavities surrounding the ovum (black arrows), vacant areas in the ovary stroma (blue arrows), only one follicle showed nucleus (∗), OES: optical empty spaces, OFD: ovarian follicle denudation, and E: edema. (d) Ovary from rats treated with plant extract plus estradiol: degenerative different ovarian follicles (arrows) and disruption of the area that surrounded the ovum (∗) and vacuolated the antrum (V) (H&E, ×100).