Hindawi Publishing Corporation Evidence-Based Complementary and Alternative Medicine Volume 2014, Article ID 642942, 12 pages http://dx.doi.org/10.1155/2014/642942 Review Article Cinnamon: A Multifaceted Medicinal Plant Pasupuleti Visweswara Rao1,2 and Siew Hua Gan2 1 FacultyofAgroBasedIndustry,UniversitiMalaysiaKelantan,JeliCampus,LockedBagNo.100,17600Jeli,Kelantan,Malaysia 2 Human Genome Centre, School of Medical Sciences, Universiti Sains Malaysia, 16150 Kubang Kerian, Kelantan, Malaysia Correspondence should be addressed to Pasupuleti Visweswara Rao; [email protected] Received 1 January 2014; Accepted 12 March 2014; Published 10 April 2014 Academic Editor: Mohammad Amjad Kamal Copyright © 2014 P. V. Rao and S. H. Gan. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Cinnamon (Cinnamomum zeylanicum, and Cinnamon cassia), the eternal tree of tropical medicine, belongs to the Lauraceae family. Cinnamon is one of the most important spices used daily by people all over the world. Cinnamon primarily contains vital oils and other derivatives, such as cinnamaldehyde, cinnamic acid, and cinnamate. In addition to being an antioxidant, anti-inflammatory, antidiabetic, antimicrobial, anticancer, lipid-lowering, and cardiovascular-disease-lowering compound, cinnamon has also been reported to have activities against neurological disorders, such as Parkinson’s and Alzheimer’s diseases. This review illustrates the pharmacological prospective of cinnamon and its use in daily life. 1. Introduction extracted from cinnamon and berries also possess antioxi- dant activities [10, 12]. The bark of various cinnamon species is one of the most important and popular spices used worldwide not only for cooking but also in traditional and modern medicines. Over- 2. Methodology all, approximately 250 species have been identified among the cinnamon genus, with trees being scattered all over the world The current review was conducted using a complete and [1, 2]. organizedsearchoftheavailableliteratureonthemedicinal Cinnamon is mainly used in the aroma and essence plantcinnamonfrom1982to2013.Thesearcheswere industries due to its fragrance, which can be incorporated performed using various databases, including PubMed into different varieties of foodstuffs, perfumes, and medicinal (http://www.ncbi.nlm.nih.gov/pubmed), Science Direct products [3]. The most important constituents of cinnamon (http://www.sciencedirect.com/), Scopus (http://www.scopus are cinnamaldehyde and trans-cinnamaldehyde (Cin), which .com/), Scirus (http://www.scirus.com/), and Google Scholar are present in the essential oil, thus contributing to the (http://www.scholar.google.com/). fragrance and to the various biological activities observed with cinnamon [4]. A study on Cinnamomum osmophloeum 3. Traditional Uses (C. osmophloeum) indicated that the essential oil from cin- namon leaves contains a high level of Cin. Consequently, In addition to being used as a spice and flavoring agent, C. osmophloeum is also used as an alternative spice for C. cinnamon is also added to flavor chewing gums due to its cassia [5]. One of the major constituents of essential oil mouthrefreshingeffectsandabilitytoremovebadbreath[13]. extracted from C. zeylanicum named (E)-cinnamaldehyde Cinnamon can also improve the health of the colon, thereby has an antityrosinase activity [6], while cinnamaldehyde is reducing the risk of colon cancer [14]. the principal compound responsible for this activity [7]. Cinnamon is a coagulant and prevents bleeding [15]. Cinnamon bark contains procyanidins and catechins [8]. Cinnamon also increases the blood circulation in the uterus The components of procyanidins include both procyani- and advances tissue regeneration [16]. This plant plays a vital din A-type and B-type linkages [9–11]. These procyanidins role as a spice, but its essential oils and other constituents also 2 Evidence-Based Complementary and Alternative Medicine O O O H OH O (a) Cinnamaldehyde (b) Cinnamic acid (c) Cinnamyl acetate Figure 1: Cinnamyl group-containing compounds. H HO (a) -Thujene (b) - (c) -Cubebene Terpineol Figure 2: Endocyclic double bond-containing compounds. have important activities, including antimicrobial [17–20], Table 1: Chemical constituents of different parts of cinnamon136 [ ] antifungal [21], antioxidant [22–26], and antidiabetic [27–33]. (Vangalapati et al., 2012 [2]). Cinnamonhasbeenusedasanti-inflammatory[34–36], antitermitic [36], nematicidal [37, 38], mosquito larvicidal Part of the plant Compound Cinnamaldehyde: 1.00 to 5.00% [39], insecticidal [40], antimycotic, [40–43] and anticancer Leaves agent [44–47]. Cinnamon has also been traditionally used as Eugenol: 70.00 to 95.00% tooth powder and to treat toothaches, dental problems, oral Cinnamaldehyde: 65.00 to 80.00% Bark microbiota, and bad breath [48, 49]. Eugenol: 5.00 to 10.00% Root bark Camphor: 60.00% 4. Chemical Constituents trans-Cinnamyl acetate (42.00 to 54.00%) Fruit and caryophyllene (9.00 to 14.00%) Cinnamon consists of a variety of resinous compounds, Terpene hydrocarbons: 78.00% including cinnamaldehyde, cinnamate, cinnamic acid, and numerous essential oils [50](Table 1). Singh et al. [51] C. zeylanicum buds alpha-Bergamotene: 27.38% reported that the spicy taste and fragrance are due to the alpha-Copaene: 23.05% presence of cinnamaldehyde and occur due to the absorption Oxygenated terpenoids: 9.00% of oxygen. As cinnamon ages, it darkens in color, improving (E)-Cinnamyl acetate: 41.98% the resinous compounds [51]. Sangal reported various phys- C. zeylanicum flowers trans-alpha-Bergamotene: 7.97% iochemical properties of cinnamon (Table 2). The presence of Caryophyllene oxide: 7.20% awiderangeofessentialoils,suchastrans-cinnamaldehyde, cinnamyl acetate, eugenol, L-borneol, caryophyllene oxide, b-caryophyllene, L-bornyl acetate, E-nerolidol, -cubebene, -terpineol, terpinolene, and -thujene, has been reported [35, 36]. antioxidants have been used to delay or prevent food spoilage. The chemical structures of some important constituents Spices and medicinal plants have received rapid consideration of cinnamon are shown in Figures 1, 2, 3, 4,and5. as sources of beneficial antioxidants against various diseases [52]. Antioxidants have been considered the most important 5. Antioxidant Activity drivers in the progress and existence of humans, as they respond to free radicals and damage in metabolic diseases and Antioxidant compounds present in foodstuffs play a vital age-related syndromes of humans and other animals [53, 54]. role in human life, acting as health-protecting agents. In Mancini-Filho et al. reported various extracts of cin- addition to this role, antioxidants are one of the key additives namon, such as ether, aqueous, and methanolic extracts used in fats and oils. Even in the food processing industry, that have shown considerable antioxidant activities [22]. Evidence-Based Complementary and Alternative Medicine 3 OH OCH3 (a) Eugenol (b) -Caryophyllene (c) Ter- pinolene Figure 3: Unconjugated exocyclic double bond-containing compounds. HO H O H OH (a) E-Nerolidol (b) L-Borneol (c) Borneol Figure 4: Hydroxy-substituted aliphatic compounds. A study on rats reported that the administration of the bark essential oils were more effective than the other two com- powderof C. verum (10%) for 90 days produced antioxidant pounds [61]. In a comparative study among 26 spices, cinna- activities as indicated by cardiac and hepatic antioxidant mon showed the highest antioxidant activity, indicating that enzymes, lipid conjugate dienes, and glutathione (GSH) [55]. it can be applied as an antioxidant used in foods [62]. Another A research group reported that cinnamon oil potentially study investigated the effectiveness of a mixture of spices on exhibits superoxide-dismutase- (SOD-) like activity as indi- oxidative stress markers as well as the antioxidant activity in cated by the inhibition of the inhibiting capacity of pyrogallol high fructose-fed insulin-resistant rats. The mixture, which autoxidation [56]. consisted of 1 g/100 g cinnamon bark, showed a significant The aqueous and alcoholic extract (1 : 1) of cinnamon antioxidant activity compared to the fructose alone group potentially significantly inhibits fatty acid oxidation and [63]. Volatile oils from C. zeylanicum showed significant lipid peroxidation in vitro [23]. Different flavonoids isolated biological activities [64]. from cinnamon have free-radical-scavenging activities and Forty-one different volatile compounds in the bark oil antioxidant properties [57]. A study of the inhibitory effects of of cinnamon have been identified and were found to vary cinnamaldehyde and other compounds of cinnamon on nitric significantly in percentage composition depending on the oxide production revealed that cinnamaldehyde possesses growth stages and segments of the C. cassia tree [65]. potentialactivityagainsttheproductionofnitricoxideas To extract essential oil for industrial use, the yields and well as the expression of inducible nitric oxide. The highest compositions of bark oil during Cinnamomum cassia growth inhibitory activities were reported as 81.5%, 71.7%, and 41.2% (1–3 years old for the branch bark and 5–12 years old for the at 1.0, 0.5, and 0.1 g/L, respectively [58]. Lin et al. reported stem bark) were determined. These researchers also found the in vivo antioxidant activity of two different