What Is Chen Pi
Chen Pi commonly known as Citri Reticulatae Pericarpium or Tangerine Peel is the dried mature pericarp of Citrus reticulata Blanco and its cultivars, which is a small tree belonging to the family Rutaceae. It is a relatively practical and common Chinese herbal medicine, which first appeared in <Shennong Ben Cao Jing> in the late Western Han Dynasty (around 100 BCE).
Citrus reticulata Blanco also known as Mandarin orange is a common evergreen fruit tree. They have been cultivated for more than 3,000 years. They prefer a warm and humid climate and are suitable for planting in loose, fertile, well-drained, slightly acidic to neutral soil. They are mainly distributed in the Guangdong, Guangxi, Sichuan, Fujian, and Zhejiang Provinces of China.
The cultivars of C. reticulata Blanco mainly include C. reticulata “Chachi”, C. reticulata “Dahongpao”, C. reticulata “Unshiu”, and C. reticulata “Tangerina”. Among them, C. reticulata “Chachi” is mainly distributed in the Xinhui of Jiangmen and Sihui of Zhaoqing in Guangdong province. Its ripe peel is also known as Guang Chen Pi or Xin Hui Chen Pi. Traditionally, Xin Hui Chen Pi is considered to be a Daodi medicinal material.
In late autumn and early winter, people gather the ripe fruits of Citrus reticulata Blanco and its cultivars, peel their peels, dry them in the sun or dry them at low temperatures, and make them into Chinese herbal medicines.
Chen Pi contains α-thujene, α-pinene, β-pinene, α-phellandrene, α-terpineol, β-phellandrene, β-myrcene, limonene, 3-carene, 4-carene, linalool, citronellal, furfural, α-terpinene, copaene, β-caryophyllene, α-caryophyllene, germacrene d, α-farnesene, δ-cadinene, γ-elemene, sabinene, terpinolene, nonanal, citronellol, carvone, perillaldehyde, thymol, dodecanal, palmitic acid, cymene, 4-terpineol, methyl 2-(methylamino) benzoate, α-sinensal, 3,7-dimethyl-7-octenealdehyde, 2-methyl-5-(1-methyl ethyl)-phenol, z-β-ocimene, β-eucalyptol, dodecanoic acid, eriocitrin, narirutin, hesperidin, neohesperidin, poncirin, melitidin, luteolin-7-o-rutinoside, naringin, diosmin, naringenin, hesperetin, sinensetin, pentamethoxyflavone, nobiletin, synephrine, N-methyl tyramine, organic acids, inositol, vitamin B, vitamin C, carotenoids, pectin, polysaccharides, thymol, β-sitosterol, and some trace elements.
Generally, the bright Chen Pi with a strong fragrance is preferred. The Chinese medical theory is that the longer the storage time, the better the quality of Chen Pi.
According to the Chinese Pharmacopoeia, the medicinal nature of Chen Pi is relatively warm, with a bitter and pungent taste. It has a certain therapeutic effect on the pathological changes of the spleen and lung meridians.
In traditional Chinese medicine, it is often used to regulate qi and invigorate the spleen, eliminate dampness and phlegm, and treat abdominal fullness and distention, nausea, vomiting, indigestion, anepithymia, diarrhea, cough, expectoration, anabole, vomiting of watery fluid, hiccup, coronary heart disease angina pectoris, cor pulmonale, arrhythmia, palpitations, chest discomfort, oppression in the chest, stomach pain, chronic atrophic gastritis, ulcerative colitis, acute mastitis, chronic bronchitis, asthma, postoperative delayed gastric emptying and prevent postoperative abdominal distension after abdominal surgery.
There are thousands of traditional Chinese medicine prescriptions containing it, such as Ping Wei San, Bao He Wan, and Jian Pi Wan.
- Anti-inflammation, reducing LPS-induced NO release and IL-6 generation and inhibiting protein expression of iNOS and COX-2 in RAW 264.7 cells .
- Anti-oxidation, scavenging hydroxyl free radicals and DPPH radicals, reducing ferric ion (Fe3+) to the ferrous ion (Fe2+) .
- Reducing CCL4-induced acute liver injury in mice and protecting the liver .
- Regulating qi and invigorating the spleen, treating abdominal fullness and distention, poor appetite, vomiting, and diarrhea caused by stagnation of gastrosplenic qi, and stagnation of cold-dampness in middle-jiao.
- Regulating the flow of vital energy, and treating vomiting and hiccup caused by heat, cold, or a mixture of deficiency and excess syndrome.
- Regulating the flow of qi and relieving depression in the chest, treating damp phlegm and cold phlegm syndrome.
- Promoting the circulation of qi and relieving the obstruction, treating chest discomfort, oppression in the chest, and shortness of breath caused by phlegm and qi obstructing each other.
- Hesperidin inhibited collagen-, arachidonic acid (AA)-, ADP-, and thrombin-induced rat platelet aggregation in vitro and ex vivo .
- Hesperidin has an inhibitory effect against the development of neurodegenerative diseases such as Parkinson’s, Alzheimer’s, Huntington’s diseases, and multiple sclerosis .
- Its extract reduced blood pressure levels in HFD/STZ-induced diabetic rats .
- Its extract decreased plasma levels of total cholesterol, triglycerides, LDL, AST, and ALT and increases plasma HDL levels in diabetic rats .
- Its supercritical fluid extract possessed in vitro antiviral activity against the respiratory syncytial virus (RSV) .
- Its flavonoids have inhibitory effects on cancers such as breast, lung, prostate, liver, stomach, colon, esophagus, cervical, bladder, and human chondrosarcoma .
- Studies have found that its alkaloid fraction and synephrine protected Guinea pigs against histamine-induced experimental asthma in a dose-dependent manner .
- Studies have found that chronic administration of tangerine peel extract confers protection against vascular inflammation and endothelial dysfunction in arteries from diabetic rats, possibly via AMPK activation .
- It can be used in combination with Mu Xiang (Radix Aucklandiae), Zhi Shi (Fructus Aurantii Immaturus), etc., to treat abdominal fullness and distention, poor appetite, vomiting, and diarrhea caused by stagnation of gastrosplenic qi.
- It can be used in combination with Cang Zhu (Rhizoma Atractylodis), Hou Po (Magnolia Bark), etc., to treat abdominal fullness and distention, poor appetite, vomiting, and diarrhea caused by stagnation of cold-dampness in the spleen and stomach.
- It can be used in combination with Shan Zha (Hawthorn Fruit), Shen Qu (Medicated Leaven), etc., to treat abdominal distension and pain caused by retention of food leading to stagnation of qi.
- It can be used in combination with Ren Shen (Radix et Rhizoma Ginseng), Bai Zhu (Rhizoma Atractylodis Macrocephalae), Fu Ling (Poria), etc. to treat anorexia and abdominal distension after eating caused by qi stagnation due to spleen-asthenia.
- It can be used in combination with Zhu Ru (Bamboo Shavings), Zhi Zi (Fructus Gardeniae), etc. to treat vomiting and hiccup caused by heat.
- It can be used in combination with Ban Xia (Pinellia Rhizome), Fu Ling (Poria), etc. to treat cough caused by damp-phlegm syndrome.
- It can be used in combination with He Ye (Folium Nelumbinis) and Sha Ren (Fructus Amomi) to treat ulcerative colitis.
- It can be used in combination with Zhi Shi (Fructus Aurantii Immaturus), Sheng Jiang (Rhizoma Zingiberis Recens), etc. to treat chest discomfort, oppression in the chest, shortness of breath caused by phlegm and qi obstructing each other.
- At present, there is no literature report that Chen Pi has toxic effects, and no data is showing that taking it at the prescribed dose can cause serious adverse reactions.
Precautions and Warnings
- The dosage of Chen Pi should be controlled between 3-10g.
- It can be made into decoctions, pills, powders, or teas.
- It should not be eaten with raw and cold foods.
- People who are allergic to Chen Pi should not take it.
- It should not be taken by people who have an internal sthenic fever and a reddish tongue with scanty fluid.
- Patients with hemoptysis or hematemesis should not take it.
- Pregnant and breastfeeding women should take it under medical supervision.
- Children, the elderly, and the infirm should take it under medical supervision.