Orange Peel

Chinese name: Chen pi
Medical Name:
Latin Name: Citrus aurantium
Property: Warm
Taste: Bitter, pungent

Quotes from Chinese historical sources

Western Research

Biofactors. 2007;31(1):17-24.
Antidiabetic potential of Citrus sinensis and Punica granatum peel extracts in alloxan treated male mice.
Parmar HS, Kar A.
School of Life Sciences, Devi Ahilya University, Takshashila Campus, Khandwa Road Complex, Indore, M.P., India. hamendrasingh999@yahoo.co.in
An investigation on the effects of four different concentrations of peel extract from Citrus sinensis (CS) or Punica granatum (PG) in male mice revealed the maximum glucose lowering and antiperoxidative activities at 25 mg/kg of CS and 200 mg/kg of PG. In a separate experiment their potential was evaluated with respect to the regulation of alloxan induced diabetes mellitus. While a single dose of alloxan (120 mg/kg) increased the serum levels of glucose and alpha-amylase activity, rate of water consumption and lipid peroxidation (LPO) in hepatic, cardiac and renal tissues with a parallel decrease in serum insulin level, administration of 25 mg/kg of CS or 200 mg/kg of PG was found to normalize all the adverse changes induced by alloxan, revealing the antidiabetic and anti peroxidative potential of test fruit peel extracts. Subsequent phytochemical analysis indicated that the high content of total polyphenols in the test peels might be related to the antidiabetic and antiperoxidative effects of the test peels.

J Nutr Sci Vitaminol (Tokyo). 2008 Oct;54(5):409-15.
Inhibitory effect of pectin from the segment membrane of citrus fruits on lipase activity
Edashige Y, Murakami N, Tsujita T.
Faculty of Agriculture, Ehime University, Matsuyama, Japan. yedash@agr.ehime-u.ac.jp
Segment membranes from 4 citrus species selected from 4 sections were treated with water to obtain polysaccharides containing pectin. The extracts, which inhibited pancreatic lipase activity in a concentration-dependent manner, were divided into high molecular weight fractions [molecular weight (M.W.) >300,000], which inhibited the activity strongly, and low molecular weight fractions (M.W. <300,000), which did not show such strong inhibition. The high molecular weight fractions were composed mainly of a characteristic sugar of pectin, namely, galacturonic acid. A galacturonic acid-rich fraction purified by anion exchange chromatography from a water extract also strongly inhibited the activity. The inhibitory activity of the high molecular weight fraction was much stronger than that of commercial citrus pectin. The results suggest that pectin from segment membranes of citrus fruits might be useful as a functional food, especially as a fat-reducing material.

Nutr Cancer. 2008;60 Suppl 1:70-80
Citrus compounds inhibit inflammation- and obesity-related colon carcinogenesis in mice
Tanaka T, Yasui Y, Ishigamori-Suzuki R, Oyama T.
Kanazawa Medical University, Daigaku, Uchinada, Ishikawa, Japan. takutt@kanazawa-med.ac.jp
Dietary polyphenols are important potential chemopreventive natural agents. Other agents, such as citrus compounds, are also candidates for cancer chemopreventives. They act on multiple key elements in signal transduction pathways related to cellular proliferation, differentiation, apoptosis, inflammation, and obesity. This short review article provides our findings of preclinical studies on potential chemopreventive activities of dietary citrus compounds, auraptene, collinin, and citrus unshiu segment membrane (CUSM), using clitis- and obesity-related colon tumorigenesis models. Dietary feeding with auraptene and collinin at dose levels of 0.01% and 0.05% significantly lowered the incidence (50-60% reduction) and multiplicity (67-80% reduction) of colonic adenocarcinomas induced by azoxymetahene [AOM, single intraperitoneal injection of 10 mg/kg body weight (bw)] and dextran sodium sulfate (1% in drinking water). Anti-inflammatory potency of aurapene and collinin may contribute to the effects. Administration with CUSM at 3 doses in diet significantly inhibited development of aberrant crypts foci induced by 5 weekly subcutaneous injections of AOM (15 mg/kg bw) in male db/db mice: 53% inhibition by 0.02% CUSM, 54% inhibition by 0.1% CUSM, and 59% inhibition by 0.5% CUSM. CUSM treatment also decreased serum level of triglycerides. Our findings suggest that certain citrus materials are capable of inhibiting clitis- and obesity-related colon carcinogenesis.

Nat Prod Res. 2008;22(17):1544-51.
Protective effects of a standardised red orange extract on air pollution-induced oxidative damage in traffic police officers.
Bonina FP, Puglia C, Frasca G, Cimino F, Trombetta D, Tringali G, Roccazzello A, Insiriello E, Rapisarda P, Saija A.
Departmento Scienze Farmaceutiche, University of Catania, Catania, Italy.
Several pathological conditions have all been associated with a higher release of atmospheric pollutants. There is growing evidence that oxidative stress may represent one of the agents involved in the initiation and/or progression of many of these pathologies. The aim of the present study was to evaluate the effects of short-term dietary supplementation with a standardised red orange extract (ROC) on a group of traffic police officers exposed to traffic exhaust pollution and cigarette smoking, by measuring some noninvasive biomarkers of oxidative stress. At the beginning of the study, all the groups showed similar serum lipid hydroperoxide levels, but traffic officers showed lower serum concentrations of thiol (SH) groups; furthermore, the frequency of spontaneous sister chromatide exchanges (SCEs) in peripheral lymphocytes was increased by smoking (but not by pollution exposure alone) at a higher degree in subjects exposed to traffic pollution. After 1 month of ROC administration, serum lipid hydroperoxide levels decreased only in all non-smoking subjects; furthermore, SH group levels measured in traffic officers appeared restored to normal values observed in the respective controls. Finally, the increase in SCE frequency induced by smoking was reduced by treatment with ROC especially in traffic officers. Our study suggests that ROC supplementation could be useful to minimise the detrimental effects caused by exposure to air pollution and smoking.

Planta Med. 2009 Jan;75(1):62-4. Epub 2008 Nov 24
Antioxidant activity of citrus cultivars and chemical composition of Citrus karna essential oil.
Malhotra S, Suri S, Tuli R.
National Botanical Research Institute, Lucknow, India. malhotra54@rediffmail.com
The genus Citrus has a number of species and hybrids that are well established for their pharmaceutical and economic importance. The essential oil from Citrus karna Raf (Rutaceae) was analyzed for D-limonene (92.31%), the major chemical constituent, along with other minor constituents such as alpha-pinene (1.23%) and beta-pinene (1.80%). It showed significant inhibition for the oxidation of linoleic acid in the beta-carotene-linoleic acid system. Essential oils A and B obtained from C. sinensis, with 35.08% and 76.68% d-limonene, respectively, were used to evaluate the effect of the d-limonene concentration on antioxidant potential. Studies showed that d-limonene and C. karna essential oil have a similar antioxidant potential (39.6 and 38.3%, respectively). C. sinensis oils A and B showed only 10.5% and 30% antioxidant potential, respectively, indicating the possible role of d-limonene in antioxidant activity.

Carbohydr Res. 2008 Sep 26.
Modified citrus pectin anti-metastatic properties: one bullet, multiple targets.
Glinsky VV, Raz A.
Harry S. Truman Memorial Veterans' Hospital, Columbia, MO 65201, USA; Department of Pathology and Anatomical Sciences, University of Missouri, Columbia, MO 65212, USA.
In this minireview, we examine the ability of modified citrus pectin (MCP), a complex water soluble indigestible polysaccharide obtained from the peel and pulp of citrus fruits and modified by means of high pH and temperature treatment, to affect numerous rate-limiting steps in cancer metastasis. The anti-adhesive properties of MCP as well as its potential for increasing apoptotic responses of tumor cells to chemotherapy by inhibiting galectin-3 anti-apoptotic function are discussed in the light of a potential use of this carbohydrate-based substance in the treatment of multiple human malignancies.

Bioorg Med Chem. 2009 Jan 1;17(1):25-8.
Identification and physiological evaluation of the components from citrus fruits as potential drugs for anti-corpulence and anticancer.
Hirata T, Fujii M, Akita K, Yanaka N, Ogawa K, Kuroyanagi M, Hongo D.
Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8526, Japan. hirata-001@hiroshima-u.ac.jp
On the basis of monitoring the prevention of accumulation of lipid droplets in mouse 3T3-L1 preadipocyte cells and inhibition of the proliferation of human colon cancer HT-29 cells, effective anti-corpulence and anticancer compounds were isolated from the peel of Citrus fruits. These bioactive components were identified as polymethoxyflavones and coumarin derivatives by spectroscopic analyses. 5-Hydroxy-6,7,8,3',4'-pentamethoxyflavone had the greatest anti-corpulence effects and 3,5,6,7,8,3',5'-heptamethoxyflavone had the greatest anticancer effects. Furthermore, distributions of those bioactive components in the peel of 10 species of Citrus fruits were demonstrated by HPLC analyses.