The Potency of Cinnamomum Zeylanicum to Prevent Diseases: a Review

Plants are an important source of traditional medicines that can be used to improve health. Cinnamon (Cinnamomum zeylanicum) has long been recognized to have many benefits. Cinnamon was used traditionally as a remedy for arthritis, diarrhea, allergies and ulcers. This literature review aimed to identify the bioactive compounds and bioactivity of cinnamon. Literature searches used PubMed and Google Scholar. A total of 55 full text articles met the inclusion criteria of the review. The extract or essential oil of cinnamon contains many bioactive compounds, such as eugenol, cinnamic acid, linalool, β-caryophyllene, coumarin, trans cinnamyl acetate, and 1.8 cineole. These compounds have several bioactivities including anti-cancer, anti-arrhythmia, antiinflammatory, anti-diabetic, anti-atherosclerosis, anti-cholinesterase, and anti-lipid oxidation. Cinnamon extract has an excellent potential as an antioxidant and antidiabetic agent. Its potential and unique taste has contributed to its wide use in herbal remedies.


Introduction
The use of cinnamon as a traditional herbal therapy or alternative complementary medicine has spread all over the world. Cinnamon was used traditionally as a remedy for arthritis, diarrhea, allergies and ulcers.

Eureka Herba Indonesia
Journal Homepage: https://eurekabiomedical.com/index.php/EHI PubMed and Google Scholar were used as the searching engine in this study. The searching was conducted up to May 21, 2020 using the keywords "Cinnamomum zeylanicum" and "antioxidant" or "Cinnamomum zeylanicum" and "α-glucosidase".
Articles selected were all published within the past ten As many as 55 full text articles were included in the review.

Results and discussion
Based on the results from the reviewed studies, we found that cinnamon extract (Cinnamomum zeylanicum) has several powerful bioactive compounds (Table 1).  13 A study also found that cinnamaldehyde increases the activity of glucose transporter 4 (GLUT 4) which transports blood glucose into cells to diminish the blood glucose levels. 14 Cinnamaldehyde also has antioxidant activity. 15

Eugenol
Eugenol (C10H12O2) is a widely known and volatile component in clove extracts, but it is also found in cinnamon, especially in the leaves. 16,17 The study conducted by Rao et al. compared the bioactive compounds in the essential oil of cinnamon leaves and reported that eugenol compounds were found mostly on the top and larger leaves. Apart from the leaves, eugenol is also found in the bark of cinnamon. 17 Eugenol was also found in the essential oil of cinnamon bark between 4.6 % -7.45 %. 6,18 . The eugenol of essential oil of cinnamon leaves is as much as 58.10 %. 19 The methanolic extract of cinnamon bark contains as much as 10.97 % of eugenol. The eugenol has strong antioxidant activity, but also has cytotoxic effects when used in high doses. Further research is needed to confirm eugenol's use as a safe pharmacological agent. 12 Eugenol is not found in the ethanolic extract.

Cinnamic acid
Cinnamic acid (C9H8O2) is a compound found in cinnamon bark, derived from phenylalanine deamination. 20 Cinnamic acid has low toxicity and a broad spectrum of biological activity. 21 Generally, it is used as an antimicrobial agent. 22 Cinnamic acid is found in the cinnamon water extracts as much as 1.0 mg/g. 23 The methanolic and ethanolic extracts contain 0.68 ± 0.01 mg/g and 8.99 ± 0.5 mg/g, respectively. 10-12 Cinnamic acid derivates have phenolic hydroxyl groups, so they are often associated with antioxidants. Cinnamic acid has been reported as an antioxidant, antibacterial, antiviral, and anti-fungal agent. 12

Linalool
Linalool (C10H18O) is the main bioactive compound in cinnamon essential oil. 18,24 The concentration of linalool in the essential oil of the leaves is around 85.7%. 19,25,26 Linalool in the essential oil of the bark is 7%. 6 The presence of a higher linalool content will give the essential oil more flavor and aroma. 27

Coumarin
Coumarin is found in aqueous and methanolic extracts of cinnamon. The methanolic extract contains 4.4 ± 0.10 mg/g of coumarin and the water extract contains as much as 4.8 mg/g of coumarin. 11,23

Trans-cinnamyl acetate
Cinnamyl acetate (C11H12O2) is an acetate ester produced by the condensation of cinnamyl alcohol and acetic acid. This compound is found in cinnamon leaf oil. This compound has the potential as a fragrance, metabolite, and insecticide. 30 The cinnamon essential oil of leaves and bark contain cinnamyl acetate as much as 23.7% and 4.98%, respectively.

Anti-inflammatory
Cinnamon has strong antioxidant and antiinflammatory activities. 23 Its antioxidants contribute to the anti-inflammatory activity. 41 Cinnamon inhibits the synthesis of COX-2 and prostaglandins. 41,42 Cinnamaldehyde and linalool play an important role as

Anti-diabetic
Antioxidant compounds of the cinnamon extract improve oxidative stress and reduces blood glucose levels in diabetic-induced mice. 44 Figure 3 shows