The white-flowered sour vine fruit, also known as "yang gong ban zi", "niu pi rui", "niu wei teng", and "wu ya tang", is a plant belonging to the Asclepiadaceae family. It is mainly distributed in southern China, including Hainan, and the medicinal part is the root of the white-flowered sour vine fruit. It has the effects of clearing heat and dampness, stopping bleeding, and reducing inflammation.
【Morphology of the Plant】
It is a climbing shrub, growing 3-6m tall, with slender branches and the whole plant covered with hair on the inflorescence. The bark is gray-brown, and there are obvious lenticels on the old branches. The leaves are tough and papery, inversely ovate or elliptic-oval in shape, 5-8cm long and 1.5-3.6cm wide, with blunt tapering tips and wedge-shaped or nearly circular bases. They are slightly wrinkled, with entire margins, and the back is usually slightly powdery. The petioles are 5-8mm long. The large cone-shaped inflorescence is terminal, 5-20mm long, rarely reaching 30cm. The flower stalks initially slant outwards and then radiate outwards, perpendicular to the overall flower stalk, covered with fine soft hairs. The flowers are small and numerous, 1.5-3mm long, with 5 small triangular sepals on the back covered with fine soft hairs and opaque glandular dots. The corolla is pale green or white, 5-lobed, with overlapping scales arranged like tiles, 1.5-2mm long, and densely covered with papillary projections on the edges and inner surface. The fruits are spherical or ovoid, 3-4mm in diameter, purple-black, with obvious fruit stalks. The flowering period is from April to May, and the fruiting period is from June to July. It mostly grows in sunny places.
【Distribution】
It is found in Lingshui, Ding'an, Lingao, and Baoting in Hainan. It is also distributed in southern China. It can also be found in Sri Lanka, India, Indonesia, and other countries.
【Medicinal Uses】
Its taste is sour, sweet, and neutral. It enters the liver and spleen meridians. The root is used as medicine and has the effects of clearing heat and dampness, stopping bleeding, and reducing inflammation. It is mainly used to treat acute gastroenteritis, dysentery, and bleeding from knife wounds, etc. The fruit is edible, and the bark and leaves have astringent properties.
【Pharmacological Research】
(1) Effects on the reproductive system
It has been reported that xintongzi quinone has contraceptive activity in both male and female mammals. Xintongzi quinone can increase the weight of the ovaries in female animals and inhibit implantation, decrease plasma progesterone concentration and semen volume, and reduce sperm activity in male animals.
Research has found that subcutaneous injection of xintongzi quinone suspension at a dose of 20mg/kg per day in adult male rats for 15 days resulted in a significant decrease in epididymal sperm viability and motility. The daily production of sperm also significantly decreased. The epididymal epithelium showed hypertrophy and dilation, and the structure of the convoluted seminiferous tubules was disrupted. The mitochondria of sperm showed significant vacuolar changes, and the transformation of round sperm into elongated sperm was hindered. Some interstitial cells showed mitochondrial condensation and matrix swelling. There were no apparent toxic side effects in animals during the administration period, and they quickly recovered after discontinuation for 20 days. In India, white-flowered sour vine fruit is used as a contraceptive and can inhibit alkaline phosphatase activity in the endometrium.
(2) Insecticidal and antibacterial effects
Studies have shown that the ethanolic extract of white-flowered sour vine fruit has a 93% insecticidal effect. The aqueous and methanol extracts of white-flowered sour vine fruit also have a moderate antibacterial activity.
