Kadsura coccinea (Lem.) A. C. Smith is a perennial evergreen vine of the family Schisandraceae. It is cultivated mainly in southern China, Vietnam, and Thailand. The roots and stems of K. coccinea are used as traditional Chinese medicine to treat gastroenteric disorders, rheumatism, trauma, and pain (State Administration of Traditional Chinese Medicine, 1999). The chemical composition and biological activities of the roots and stems have been widely studied and reviewed (Yang et al., 2020). At present, more than 200 types of compounds have been identified in the roots and stems of K. coccinea; they show various bioactivities, including anti-inflammatory, antitumor, antiviral, and anti-hepatitis (Jia et al., 2021; Yang et al., 2020, 2022).

The fruit of K. coccinea, also known in China as “Xuetengguo”, is an edible aggregate fruit with a good taste and fragrance. The fruit is also a Dong ethnomedicine used by the people of Dong Nationality to treat abnormal menstruation, menopausal syndrome, and female infertility (Hunan Food and Drug Administration, 2009). However, the active compounds and underlying mechanisms are still unclear. To date, only some polyphenols (protocatechuic acid, rutin, etc.), lignans (heilaohuguosus A-S, etc.), and polysaccharides have been identified in this fruit (Jia et al., 2021; Liu and Li, 1995; Long et al., 2022; Sritalahareuthai et al., 2020; Sun et al., 2009), and no studies have been performed to evaluate its estrogenic effects.

Menopause occurs naturally in most women between the ages 45–52 as a result of ovarian senescence. More than 85% of these women experience problematic symptoms, including hot flashes, night sweats, sleep disturbances, sexual dysfunction, mood disorders, weight gain, and cognitive declines (Sussman et al., 2015). Hormone therapy is the primary treatment for menopausal symptoms (“The Hormone Therapy Position Statement of The North American Menopause Society” Advisory Panel, 2022). However, many women are unwilling to use hormone therapy because of adverse reactions and switch to complementary and alternative medicines (Johnson et al., 2019).

Phytoestrogens are plant-derived compounds that are similar to estradiol in their chemical structure and function. They are the most popular alternative approaches for menopausal symptoms (Johnson et al., 2019; Petrine and Del Bianco-Borges, 2021). Many phytoestrogens such as soy isoflavones (Baranska et al., 2022; Sathyapalan et al., 2018), black cohosh (Cimicifuga racemose) extract (Mohapatra et al., 2022), Salvia officinalis extract (Wilfried et al., 2021; Zeidabadi et al., 2020) and evening primrose (Oenothera biennis) oil (Farzaneh et al., 2013; Mahboubi, 2019) have been extensively used with demonstrated effects in relieving menopausal symptoms with fewer side effects (Rowe and Baber, 2021).

In this study, volatile oil was prepared from three parts (peel, pulp, and seed) of K. coccinea fruits and analyzed using gas chromatography-mass spectrometry (GC-MS). Estrogenic activity was evaluated in vitro using cell assay and in vivo using immature rats.