Cape Jasmine Fruit (Zhi Zi)

Cape Jasmine Fruit (zhi zi, 栀子), also known as Fructus gardeniae, is the ripe fruit of Gardenia Jasminoides, an evergreen shrub of the family Rubiaceae. A popular ornamental shrub found worldwide, Gardenia has glossy, deep green leaves and white or cream flowers that turn yellow as they age. They have orange-coloured berry-like fruits that contain sticky pulp and a distinct, pleasant odour.

During the Qin and Han dynasties, Cape Jasmine Fruit was the most widely used yellow dye. Archaeology has confirmed that the yellow colour of the dyed fabrics unearthed at Ma Wang Dui, (馬王堆) was dyed with Zhi Zi. Aside from being an ornamental plant and a source of yellow dye, Zhi Zi is also used in herbal preparations. It first appeared in Shen Nong Ben Cao Jing, (神农本草经)  in the late Western Han Dynasty (around 100 BC) as a form of Chinese medicine.

From September to November each year, people gather Zhi Zi that is reddish-yellow and ripe and have its impurities removed for medicinal usage. You can use the herb directly, stir-fry it or carbonize it.

In Traditional Chinese Medicine (TCM), Zhi Zi falls under the category of ‘Herbs that clear Heat and purge Fire’. Such herbs are used to clear inflammatory and infectious conditions that are referred to as Internal Heat in TCM. Cold in nature, Zhi Zi can help individuals with too much Heat in their body, such as those experiencing a Yang Excess or a Yin Deficiency, to restore a harmonious yin-yang balance.

Bitter in taste, Zhi Zi can cleanse the body by clearing Heat, drying Dampness and promoting elimination via urination or bowel movements. In particular, the herb targets the gallbladder, the Heart, the Lungs and the San Jiao (Triple Burner).

Traditional Chinese Medicine (TCM) shows that Zhi Zi has the following health benefits.

Zhi Zi can clear Heat and purge Fire. It is indicated for lingering high fever caused by exuberant Heat in the qi system. As the herb is also great at removing toxicity to dispel irritability in the San Jiao, Zhi Zi is also commonly indicated for stuffiness in the chest, irritability, depression, restlessness, insomnia and delirious speech. If the symptoms are serious, you can combine Zhi Zi with other fire-purging and toxicity-relieving herbs to enhance its efficiency.

Zhi Zi is especially useful when it comes to clearing Heat in the Heart, Liver and stomach. Hence, the herb can help to relieve relevant symptoms such as restlessness and delirium due to the accumulation of Heat in the Heart, blood-shot and swollen eyes, mood swings, infantile convulsion due to Liver-Heat, epigastric pain due to stomach-Heat, mouth ulcers, sore throat and swollen gum due to the up-flaming of stomach fire. The herb may even help to manage type 2 diabetes caused by middle wasting.

Other than the above Fructus gardeniae benefits, Zhi Zi is also indicated for carious hemorrhage syndromes caused by Blood-Heat, such as hematemesis, hemoptysis, non-traumatic hemorrhage and urine bleeding. The herb’s ability to clear Heat and remove toxicity also makes it a good form of treatment for various Heat-toxin syndromes. For example, Zhi Zi can be used for pelvic inflammatory disease and red swollen abscesses caused by Heat-toxins.

In addition, Zhi Zi can dispel Dampness in the Liver and gallbladder. The herb is indicated for jaundice with scanty and dark urine caused by Damp-Heat in the Liver and gallbladder. Zhi Zi is also effective in stopping traumatic pain and relieving swelling. When raw Zhi Zi is grinded into powder and mixed with flour, egg white or smashed Chinese Chive, and applied on the affected area, it can treat the injuries from knocks and falls.

The recommended daily dosage of Zhi Zi is 5 – 15g. The unprocessed form of Zhi Zi is generally used to clear Heat and purge Fire, while the stir-baked form of Zhi Zi is mainly used to stop bleeding. Zhi Zi may also be applied directly to the skin.

Zhi Zi is available as powder, cream or decoction. Zhi Zi may also be ground into a poultice to be applied to the skin.

Zhi Zi should not be used by individuals who are experiencing excess Cold, Spleen Deficiency or stomach Deficiency. If you are experiencing reduced appetite or loose stools, it is best to avoid this herb for the time being as well.

Do note that Zhi Zi has a sedative effect and may increase drug-induced sleep time when used concurrently with other sedatives such as antihistamines, narcotic analgesics, barbiturates and benzodiazepines. Also, as Zhi Zi may lower blood pressure, it can increase the effect of anesthetics and negate the effects of hypertension medications.

Some side effects associated with Zhi Zi include dizziness, palpitations, abdominal pain, nausea, vomiting, heavy urination, general weakness, cold sweats and coma in severe cases.

Here is a summary for Cape Jasmine Fruit (Zhi Zi):

• Herb name (Chinese): 栀子
• Herb name (Pin Yin): zhī zǐ
• Herb name (English): Cape Jasmine Fruit
• Herb name (Botanical): Fructus Gardeniae
• Origin of species: Gardenia jasminoides Ellis
• Part(s) of herb used: Fruit
• Geo-specific habitat(s): Along the southern flow of Yangtze River
• Taste(s) & Properties: Bitter; Cold; Administrates the Heart, Lung and Triple Burner Meridians
• Actions: Relieves heat and eases symptoms of restlessness from heat-related illnesses; Relieves symptoms of jaundice; Eases bleeding symptoms due to heat; Reduce swelling and aid in detoxification in sores; Eases painful urination and eye discomforts

Li, C., Lan, M., Lv, J., Zhang, Y., Gao, X., Gao, X., … & Sun, J. (2019). Screening of the hepatotoxic components in Fructus Gardeniae and their effects on rat liver BRL-3A cells. Molecules, 24(21), 3920.[Accessed on 6th January 2023]

Liu, H., Chen, Y. F., Li, F., & Zhang, H. Y. (2013). Fructus Gardenia (Gardenia jasminoides J. Ellis) phytochemistry, pharmacology of cardiovascular, and safety with the perspective of new drugs development. Journal of Asian Natural Products Research, 15(1), 94-110.[Accessed on 6th January 2023]

Tian, J., Qin, S., Han, J., Meng, J., & Liang, A. (2022). A review of the ethnopharmacology, phytochemistry, pharmacology and toxicology of Fructus Gardeniae (Zhi-zi). Journal of Ethnopharmacology, 289, 114984. [Accessed on 6th January 2023]