Pharmacognosy and Health Benefits of Cinnamon

Introduction of Cinnamon

Cinnamon is a commonly used spice in many cuisines all over the world. The medicinal properties of cinnamon have been widely recognized with particular carminative activity arising from its volatile oils. The other health benefits include anti-ulcer, anti-inflammatory, anti-bacterial, antioxidant etc. The main active constituents of cinnamon are cinnamic aldehyde and eugenol. The pungent taste is attributed to cinnamic aldehyde which is a yellow in color on fresh distillation but on storage by absorption of oxygen turns dark red. The sweetness in cinnamon arises from mannitol. Cinnamon is also known as dalchini or ceylon cinnamon.

Cinnamon

Biological Source Dried bark of the shoots (stem and branches) of Cinnamomum zeylanicum
Family Laureacea
Geographical Source Cinnamon plant is indigenous to south eastern India, Sri Lanka, South America, Jamaica, Indonesia, Madagascar and West Indies.
Morphology/Macroscopical Characters
  • Cinnamon plant is a 15-20 m evergreen plant.
  • Leaves on cinnamon plants are oval lanceolate, rough textured and short. The greenish flowers on the plant have a characteristic odor whereas the fruit is one-seeded berry of 1 cm size.
  • Cinnamon is obtained in the form of quills (single or double) with longitudinal striations. Externally cinnamon bark is yellowish brown while the inner surface is more darker.
  • The length of cinnamon quills is variable whereas the diameter of quills is around 6-10 mm. Good quality cinnamon is usually not more than 0.5 mm in thickness.
  • The aromatic odor is warm, sweet and fragrant.
  • Microscopic Characters
  • Since cinnamon is a bark, there should be no microscopic epidermis and cork in the transverse section. However, residual patches of cork cells may be observed.
  • The outer layer of the bark is made up of pericycle fibres 1000-2500 μm long with lignified walls having pit canals.
  • Presence of starch grains (both compound and simple) is visible under the microscope, sized around 10μm and can be found in the phloem. It is difficult to distinguish the primary phloem, however, the secondary phloem contains phloem parenchyma with the oil and mucilage cells which produce the volatile oil constituents of the plant.
  • There are also phloem fibres and medullary rays.
  • Acicular (radiating needle like) calcium oxalate crystals can be found about 5-8μm in size.
  • The phloem parenchyma contains tannins. Presence of medullary rays in the secondary phloem is prominent which are uni- or biseriate near the cambium but become broader towards the periphery.
  • There is also presence of sclereid layers of cells along the pericycle fibres.
  • Chemistry Cinnamon mainly consists of volatile oils of which 60-80% is cinnamaldehyde (cinnamic aldehdye: C6H5CH=CHCHO). The other constituents are phenols (mainly eugenol around 5-10%) and terpenes.

    Cinnamic aldehyde

    Cinnamic aldehyde

    Eugenol

    Eugenol

    These consists of hydroxycinnamalaldehyde, trans-cinnamic acid, cinnamyl alcohol and acetate, o-methoxycinnamaldehyde, caryophylline etc. Presence of mucilage, calcium oxalate and starch is also seen. Cinnamon also contains antioxidants such as procyanidins and trace amounts of coumarins.

    Chemical Tests Test for differentiating Cinnamon from Adulterants: When extract (volatile oil) from Cinnamon oil is treated with a drop of Ferric Chloride solution it yields a pale green color. This pale green color is achieved as cinnamic aldehyde on reacting with ferric chloride gives brown color and eugenol on reacting with ferric chloride solution produces blue color. A pale green color is the result of combination of these brown and blue colors.
    The same above test when done with Oil of Cassia (also called as Chinese cassia obtained from Cinnamomum cassia) yields only brown color due to absence of eugenol and with cinnamon leaf oil yields only blue color having eugenol as the main constituent.
    Adulterants/Allied drugs/ Substitutes Adulterants:

    Cinnamon leaf oil (contains 70-95% of eugenol) and oil of cassia or Chinese cassia(contains cinnamaldehyde around 80-95% as the main constituent with no eugenol) are potential adulterants.

    Allied drugs:

    • Cayenne cinnamon obtained from the bark of cultivated Cinnamomum zeylanicum plants. these are grown in Brazil, French Guiana and some parts of West Indies. This drug is mainly obtained from the older branches and hence has lower content and therefore inferior to the original drug.
    • Cayenne loureirii or Saigon cinnamon growing on the hills of Annam is commercially important in Vietnam.
    • Java Cinnamon obtained from Cinnamomum burmanii is present as double quills and has tubular calcium oxalate crystals compared to the acicular calcium oxalate crystals in the original drug.
    Uses
  • Cinnamon is useful in number of ways but mainly as a flavouring agent.
  • Cinnamon oil has been traditionally also used as a carminative and in alleviating gastric disorders and dysmenorrhea.
  • It protects from the damaging effects of free radicals due to its anti-oxidant properties.
  • It also acts as an anti-ulcer agent, having activity against H.pylori
  • It has been proposed that it also helps in reducing LDL levels and increasing HDL levels and thereby reducing cholesterol levels.
  • It has been believed that cinnamon has anti-inflammatory properties.
  • Cinnamon also possesses anti-diabetic properties, thus keeping blood sugar level in check.
  • It is also anti-microbial in nature, inhibiting the growth of yeast, bacteria, fungi etc. Being an insect repellent is also an attribute of Cinnamon.
  • Other Notes (life cycle, extraction etc.) -
    Adverse reactions Intake of large quantities of the drug has showed increase in heart rate, breathing, perspiration and intestinal movement. This stimulated state is followed by sedative phase of sleepiness or depression. Skin irritation can also happen after prolonged and repeated contact with cinnamon. In large doses it can be harmful to the liver too.

    References:

    1. Trease and Evans’ Pharmacognosy, 16e (Evans, Trease and Evans Pharmacognosy)
      Elsevier: New York, 2009.
    2. Ara DerMarderosian, et. al. The Review of Natural Products 4th Edition.
    3. Kokate, C. K.; Gokhale, S. B.; Purohit, A. P. A textbook of Pharmacognosy, 29th ed.; Nirali Prakashan: Pune, 2009.

    About Sweety Mehta

    Studied B. Pharm. at Mumbai Educational Trust Institute of Pharmacy (Mumbai). Worked at Cipla, Mumbai as Marketing executive for 2 years and 9 months. Earned a diploma in marketing from Welingkar's Institute of Management Development and Research.