Table 1 Characteristic triterpenoids in frankincense harvested from various Boswellia species

Pentacyclic triterpenes

U

1

β-Boswellic acid (β-BA)

3α-hydroxy-urs-12-en-24-oic acid

B .carterii, B. sacra, B. serrata

[18, 29, 30]

2

3-acetyl-β-BA (Aβ-BA)

3α-O-acetyl-urs-12-en-24-oic acid

B. serrate, B .carterii

[5, 29]

3

11-keto-β-BA (Kβ-BA)

3α-hydroxy-11-oxo-urs-12-en-24-oic acid

B. carterii, B. serrata

[29, 31]

4

3-acetyl-11-keto-β-BA (AKβ-BA)

3α-O-acetyl-11-oxo-urs-12-en-24-oic acid

B. carterii, B. serrata

[31, 32]

5

12-ursene-2-diketone

urs-12-en-3,11- diketone

B. serrata

[33]

6

3-acetyl-11α-methoxy-β –BA

3α-O-acetyl-11α-methoxy-urs-12-en-24-oic acid

B. carterii

[34]

7

\

2α,3α-dihydroxy-urs-12-en-24-oic acid

B. serrata.

[35]

8

urs-12-en-3α,24-diol

3α, 24-dihydroxyurs-12-ene

B. serrata.

[35, 36]

9

α-amyrenone

urs-12-en-3-one

B. carterii, B. serrata

[27, 37]

10

3-epi-α-amyrin

3α-urs −12-en-3-ol

B. carterii, B. serrata

[27]

11

α-amyrin

3β-urs-12-en-3-ol

B. carterii, B. serrata

[27, 38]

12

3-acetyl-11-hydroxy-BA

3α-O-acetyl-11-hydroxy-urs-12-en-24-oic acid

B. serrata

[39]

13

3-acetyl-9,11-dehydro-β-BA

3α-O-acetyl-9,11-dehydro-urs-12-en-24-oic acid

B. carterii

[31]

14

9,11-dehydro-β-BA

3α-hydroxy-9,11-dehydro-urs-12-en-24-oic acid

B. carterii

[31]

15

18Hα,3β,20β-ursanediol

3, 20β-dihydroxy-urs-3-ol

B. carterii

[40]

*48

11-keto-diol

3α,24-dihydroxy-11-oxo-urs-12-ene

*

[41]

*49

11-keto-β-BA methyl ester

3α-11-oxo-urs-12-en-24-oic acid methyl ester

*

[41]

*50

acetyl-11-keto-amyrin

3β-acetyl-11-oxo-urs-12-ene

*

[41]

*51

hexanoyloxy-11-keto-β-BA (HKBA)

3α-O-n-hexanoyl-11-oxo-urs-12-en-24-oic acid

*

[42]

*52

butyryloxy-11-keto-β-BA (BKBA)

3α-O-n-butyryl-11-oxo-urs-12-en-24-oic acid

*

[42, 43]

O

16

α-Boswellic acid (α-BA)

3α-hydroxy-olean-12-en-24-oic acid

B. carterii, B. serrata

[18]

17

3-acetyl α-BA(Aα-BA)

3α-O-acetyl-olean-12-en-24-oic acid

B. serrate, B. carterii

[29, 44]

18

β-amyrenone

olean-12-en-3-one

B. carterii, B. serrata

[18]

19

3-epi-β-amyrin

3α-olean-12-en-3-ol

B. carterii, B. serrata

[18]

20

β-amyrin

3β-olean-12-en-3-ol

B. carterii, B. serrata

[18, 45]

21

\

3α,24-dihydroxy-olean-12-ene

B. serrata

[10, 36]

22

olibanumol E

3α-hydroxy-11-methoxyl-olean-12-ene

B. carterii

[46]

23

9,11-dehydro-α-BA

3α-hydroxy-9,11-dehydro-olean-12-en-24-oic acid

B. serrata

[47]

24

3-acetyl-9,11-dehydro-α-BA

3α-O-acetyl-9,11-dehydro-olean-12-en-24-oic acid

B. serrata

[44]

*53

3-acetyl-11-keto-α-BA

3α-O-acetyl-11-oxo-olean-12-en-24-oic acid

*

[48]

L

25

lupeolic acid

3α-hydroxy-lup-20(29)-en-24-oic acid

B. carterii

[21]

26

acetyl-lupeolic acid

3α-O-acetyl-lup-20(29)-en-24-oic acid

B. carterii

[21]

27

lupenone

lup-20(29)-en-3-one

B. frereana

[18]

28

epi- lupeol

3α-lup-20(29)-en-3-ol

B. frereana

[18]

29

lupeol

3β-lup-20(29)-en-3-ol

B. frereana, B. carterii

[18, 29]

30

3-acetyl-28-hydroxy-lupeolic acid

3α-O-acetyl-28-hydroxy-lup-20(29)-en-24-oic acid

B. carterii

[49]

31

3-acetyl-27-hydroxy-lupeolic acid

3α-O-acetyl-27-hydroxy-lup-20(29)-en-24-oic acid

B. papyrifera

[7]

32

methyl-3α-O-acetyl-27-hydroxy-lupeolic acid

3α-O-acetyl-27-hydroxy-lup-20(29)-en-24-oate

B. papyrifera

[7]

33

olibanumol F

3α-lup-20(29)-en-3- acid ester

B. carterii

[46]

34

olibanumol G

3α,5α-dihydroxy-lup-20(29)-en-24-oic acid

B. carterii

[46]

Tetracyclic triterpenes

T

35

α-elemolic acid

3α-hydroxy-tir-8,24-dien-21-oic acid

B. carterii, B. serrata

[25, 50]

36

elemonic acid (3-oxo-tirucallic acid)

3-oxo-tir-8,24-dien-21-oic acid

B. carterii, B. serrata

[9, 25, 29]

37

β-elemolic acid

3β-hydroxy-tir-8,24-dien-21-oic acid

B. carterii, B. serrata

[25, 29, 50]

38

3β-acetoxy-tireucallic acid

3β-O-acetyl-tir-8,24-dien-21-oic acid

B. carterii

[9]

39

3α-acetoxy-tirucallic acid(B)

3α-O-acetyl-tir-8,24-dien-21-oic acid

B. serrata

[25, 51]

40

\

3α-hydroxy-tir-7,24-dien-21-oic acid

B. carterii

[50]

41

3α-acetoxy-tirucallic acid(A)

3α-O-acetyl-tir-7,24-dien-21-oic acid

B. carterii

[9, 50]

42

\

3-oxo-tir-7,9(11),24-trien-21-oic acid

B. carterii

[40]

D

43

\

3β-O-acetyl-16(S),20(R)-dihydroxy-dammar-24-ene

B. frereana

[28, 52]

44

\

3β,20(S)-dihydroxy-dammar-24-ene

B. frereana

[28]

45

\

3β-O-acetyl-20(S)-hydroxy-dammar-24-ene

B. frereana

[28]

46

20(S)-protopanaxadiol

3β-hydroxy-12β,20(S)-dihydroxy-dammar-24-ene

B. frereana

[28]

E

47

\

20,22-epoxyeupha-24-ene-3-one

B. serrata

[26]