yflavan-3,4-diol units;^1 large amounts of ca-
techins and proanthocyanidins (condensed
tannins)^2 and procyanidins; resins; mucilage;
gum; sugars; calcium oxalate; two insecticidal
compounds (cinnzelanin and cinnzelanol);^3
coumarin (lowest concentration in Ceylon
cinnamon); and others (LIST AND HO ̈RHAMMER;
RAVINDRAN).1,3–5
C. verumcinnamon bark oil contains as its
major component cinnamic aldehyde (usually
60–80%); other major constituents include
sesquiterpenoids (4–5%) (e.g.,a-humulene
andb-caryophyllene that make up 3–4% of
the total, limonene, and others), eugenol, eu-
genol acetate, cinnamyl acetate, cinnamyl
alcohol, methyl eugenol, benzaldehyde, cu-
minaldehyde, benzyl benzoate, monoterpenes
(e.g., linalool, pinene, phellandrene, and cym-
ene), carophyllene, safrole, and others (LIST
AND HO ̈RHAMMER;MASADA;RAVINDRAN).6–10
C. verumleaf oil contains high concentra-
tions of eugenol (Ceylon type 80–88%;
Seychelles type 87–96%); it also contains
many of the major constituents present in
cinnamon bark oil (e.g., benzyl benzoate
(6%), cinnamaldehyde, cinnamyl acetate,
eugenolacetate,benzaldehyde,linalool,a-ter-
pinene, and others), as well as other minor
compounds, includinga-humulene,b-caryo-
phyllene,a-ylangene, methyl cinnamate, and
cinnamyl acetate (MASADA;RAVINDRAN).5,6,10
The bark ofC. burmaniiyields 1.32% oil
containing 1,8-cineole (51.4%),a-terpineol
(12.5%), camphor (9.0%), terpinen-4-ol
(8.5%), borneol (1.8%), a-pinene (1.6%),
b-caryophyllene (1.6%), p-cymene (1.0%),
and lesser amounts of myristicin,a-humu-
lene,b-eudesmol, and others. The leaf oil
contains mostly 1,8-cineole (28.5%) and bor-
neol (16.5%) with lesser amounts ofa-terpin-
eol (6.4%), p-cymene (6.1%), spathulenol
(5.8%), terpinen-4-ol (4.1%), b-caryophyl-
lene (2.9%), and others. Eugenol is absent in
both the bark and leaf oils (RAVINDRAN).
Cassia bark (C. cassia) contains 1–2% of
volatile oil and other constituents, including
glycosides (cassioside, cinnamoside),^11 diter-
penes (cinnacassiol B and D 1 ),12,13 20 -hydox-
ycinnamaldehyde,^14 cinnamic acid, vanillic
acid, syringic acid, choline, protocatechuic
acid, condensed tannins (proanthocyanidins),
procyanidins, resins, sugars, calcium oxalate,
coumarin, mucilage, and minerals, notably
manganese (LIST AND HO ̈RHAMMER;NANJING;
RAVINDRAN).^15
Cassia bark oil grown in Australia contains
mainly cinnamic aldehyde (87%), whereas the
bark oil from trees grown in China contains
mostly (E)-cinnamic aldehyde (65.5%). Other
major constituents present in Australian bark
oil are benzaldehyde (4.7%), 2-phenylethanol
(2.5%), and 3-phenylpropanol (2.0%); others
found in lesser amounts include cuminalde-
hyde, coumarin, eugenol, linalool, ethyl
cinnamate, chavicol, and others. In Chinese
cassia bark oil, the other major constituents are
coumarin (8.7%), cinnamyl acetate (3.6%),
and 2-methoxycinnamaldehyde (2.7%); others
found in lesser amounts include benzyl benzo-
ate, cinnamyl alcohol, 2-phenylethyl acetate,
eugenyl acetate, (Z)-cinnamic aldehyde, and
others. Eugenol occurs in trace amounts (JIANG-
SU;LIST AND HO ̈RHAMMER;NANJING;RAVINDRAN).^9
The leaf oil ofC. cassiagrown in Australia
contains mostly cinnamic aldehyde (77.2%),
coumarin (15.3%), cinnamyl acetate (3.6%),
benzaldehyde (1.2%), and in lesser amounts,
4-ethylguaiacol, ethyl cinnamate, 2-pheny-
lethyl acetate,a-terpineol, terpinen-4-ol, and
others. The leaf oil of China-grown trees
contains mostly cinnamic aldehyde (74.1%),
2-methoxycinnamaldehyde (10.3%), cinna-
myl acetate (6.6%), coumarin (1.2%), and
lesser amounts of benzaldehyde (1.1%), sal-
icyaldehyde, cinnamyl alcohol, 2-phenylethyl
acetate,a-pinene, and others (RAVINDRAN).PHARMACOLOGY AND BIOLOGICAL
ACTIVITIESExtracts of the dried bark ofC. verumhave
shown in vitro inhibitory activity against
Candida albicans.^16 The essential oil of the
bark inhibits the growth of human pathogenic
fungi (Aspergillus niger,Candida albicans,
Rhizopus oligosporus) and various bacteria
(Escherichia coli, Enterobacter cloacae,Cinnamon (and cassia) 197