Actually they refer to the seeds of ginkgo tree, also known as Ginkgo biloba in Latin and Yin Xing in Chinese. This is one of rare Deciduous Trees with orange-yellow drupe fruit, which blossoms in May and matures in October. As the oldest existing plant seeds of the relict plant, it is the only one survivor in this genus. Ginko biloba grows slower but life is way much longer, even up to thousands of years. Currently the oldest ginko tree is found in Di Lin Temple, which locates in Fu Lai Mountain, Ri Zhao, Shangdong province. It is said that it dates back to Shang dynasty, more than 3,500 years ago.

The earliest evidence about Gingko biloba was found in Carboniferous nearly 3.5 billion years go. They were ever widely distributed in Europe, Asia, and America in the northern hemisphere during Jurassic Period of Mesozoic but later declined gradually in Cretaceous Period. About half million years ago, Quaternary glaciation began and the cold killed most of the ginkgopsida. Somehow only some species in China survived this disaster. Also called as living fossil and panda plant, wild Gingko biloba communities are found in just a few places in China. Due to small population and dioecious nature in the wild, to protect this rare species now most of maidenhair trees are cultivated. No doubt, all of them worldwide are all originated from China, directly or indirectly.

Ginkgo nuts are oval or subglobose, 2.5 to 3.5 long, and about 2cm in diameter. Its outer fleshy seed coat is with white powder, faint yellow or orange-yellow when ripe; middle sclerotin seed coat is white, with 2 to 3 ridges; internal membranous seed coat is with rich endosperm.

Ginkgo nuts

WHAT ARE GINKGO NUTS USED FOR? 
From the perspective of Traditional Chinese Medicine (TCM), it is sweet, bitter, puckery, neutral and with mild toxicity in nature. And it goes to meridians of lung and kidney. Main uses and indications are Asthma, cough with abundance of phlegm, vaginal discharge, cloudy urine, Spermatorrhea, frequency of urination, swelling due to unknown toxin, acne rosacea, and Psoriasis. And regular dosage is 6 to 10 grams, or 5 to 10 pieces.

RELATED CHINESE HERBAL FORMULAS
As mentioned previously, TCM practitioners use it to descend the Lung-Qi and stop wheezing. Ding Chuan Tang, from She Sheng Zhong Miao Fang (Well- Known Formulas for Preserving Health), is dedicated for asthma. Other main herbs include Ma Huang (Ephedra sinica), Su Zi (Purple Perilla Fruit), Gan Cao (Licorice Root), Kuan Dong Hua (Coltsfoot Flower), Xing Ren (Apricot Seed), Sang Bai Pi (Mulberry Root Bark), Huang Qin (Baical Skullcap Root, Scutellaria), and Ban Xia (Pinellia Rhizome).

HEALTH BENEFITS 
It is also an excellent herbal supplement and antioxidant, which contains rich ingredients like crude protein, crude fat, reducing sugar, nucleoprotein, minerals, crude fibre, and multivitamins etc. According to reliable analysis, every 100g of fresh nuts contains 13.2g protein, 72.6g carbohydrate, 1.3g fat, vitamin C, riboflavin, carotenoids, various microelements like Ca, P, Fe, Se, K, Mg, and 8 amino acids. In addition, ginkgo leaf and kernel have flavonoid glycosides and ginkgolide, which improve circulation to the coronary artery and the brain, fight against aging, sharpen memory, and help treat Alzheimer’s disease and CCCI.