Heptadecanols from the leaves of Persea americana var. americana

Article abstract of DOI:10.1016/j.foodchem.2011.11.067

From the leaves of Persea americana var. americana, eleven heptadecanol derivatives were identified. Their structures were elucidated on the basis of spectroscopic analyses. The absolute configurations were determined by chemical reaction, NOESY experiment and further comparison of the optical rotation value with the literature value. Additionally, the ratios of the contents of six heptadecanol derivatives in leaves, immature fruits, mature fruits and seeds of P. americana were estimated by LC-MS in multiple reaction monitoring (MRM) mode.

Full text of DOI:10.1016/j.foodchem.2011.11.067

Food Chemistry 132 (2012) 921–924
Contents lists available at SciVerse ScienceDirect
Food Chemistry
journal homepage: www.elsevier.com/locate/foodchem
Heptadecanols from the leaves of Persea americana var. americana
Tzong-Huei Lee , Yow-Fu Tsai , Tzu-Tien Huang , Pi-Yu Chen , Wen-Li Liang , Ching-Kuo Lee c,
a
b
a
c
c,
⇑
⇑
a
Graduate Institute of Pharmacognosy, Taipei Medical University, Taipei 110, Taiwan
Department of Chemistry, Chung Yuan Christian University, Chung-Li 320, Taiwan
School of Pharmacy, Taipei Medical University, Taipei 110, Taiwan
b
c
a r t i c l e i n f o
a b s t r a c t
Article history:
Received 26 March 2011
Received in revised form 18 October 2011
Accepted 14 November 2011
Available online 20 November 2011
From the leaves of Persea americana var. americana, eleven heptadecanol derivatives were identified.
Their structures were elucidated on the basis of spectroscopic analyses. The absolute configurations were
determined by chemical reaction, NOESY experiment and further comparison of the optical rotation value
with the literature value. Additionally, the ratios of the contents of six heptadecanol derivatives in leaves,
immature fruits, mature fruits and seeds of P. americana were estimated by LC–MS in multiple reaction
monitoring (MRM) mode.
Keywords:
Crown Copyright Ó 2011 Published by Elsevier Ltd. All rights reserved.
Persea americana
Heptadecanols
Interconversion
Leaves
1
. Introduction
The avocado (Persea americana var. americana), a fruit tree, is
the isolation and structural elucidation of the previously unre-
ported compounds.
native to tropical America, and is widely cultivated in central
and southern Taiwan. Its fruits have long been used as a healthy
food for cholesterol-lowering, blood vessel-strengthening, hor-
mone-regulating, anti-aging and constipation-preventing (Chiu &
Chang, 1998), while its leaves were reported to exhibit anti-fungal
2. Materials and methods
2.1. General procedures
Optical rotations were measured in a JASCO P-1020 polarimeter.
H and C NMR were acquired with a Bruker DRX-500 SB spec-
1
13
(Prusky, Keen, Sims, & Midland, 1982; Prusky et al., 1991), anti-
inflammatory (Adeyemi, Okpo, & Ogunti, 2002) and anti-oxidant
activities (Kim et al., 2000). Although several chemical entities
have been identified from the fruits of the genus Persea (Adikaram,
Ewing, Karunaratne, & Wijeratne, 1992; Chenga et al., 2002;
Domergue, Helms, Prusky, & Browse, 2000; Gross, Gabai, Lifshitz,
trometer. Low resolution and high resolution mass spectra were
obtained, using a Finnigan TSQ-46C EI/MS and JEOL SX-102A
HRFAB/MS, respectively. IR spectra were recorded on a Thermo
Mattson IR-300 spectrometer.
2.2. Chemicals and reagents
&
Sklarz, 1974; Hashimura, Ueda, Kawabata, & Kasai, 2001; Jac-
ques & Haslsm, 1974; Karikome, Mimaki, & Sashida, 1991; Kawag-
ishi et al., 2001; Komae & Hayashi, 1972; Oberlies, Rogers, Martin,
HPLC-grade solvents, n-hexane, ethyl acetate, acetone, and two
reagents, 2,2-dimethoxypropane and p-toluenesulfonic acid mono-
hydrate, were purchased from Merck. Open column chromatogra-
phy was performed on silica gel (70–230 mesh, Merck). TLC was
carried out on silica gel 60 F254 plates (Merck), using mixtures of
n-hexane–ethyl acetate for development and spots were detected
by spraying with vanillin-sulfuric acid, followed by heating.
&
Mclaughlin, 1998; Tomita, Lu, & Lan, 1965), the constituents of
the other parts of these plants have been rarely studied, so far.
In our preliminary pharmacological evaluation, the acetone ex-
tracts of the leaves of P. americana exhibited significant vasodilat-
ing activities at concentrations higher than 150
lg/ml (Huang,
2
004). Based on this finding, we set out to investigate the chemical
constituents of the leaves of P. americana; this has led to the isola-
tion and identification of four novel chemical entities 1–4 together
with seven known analogues 5–11 (Fig. 1). This paper deals with
2
.3. Plant materials
Fresh leaves of P. americana were collected at Madou Township,
Tainan County in September 14, 2002, and were identified by one
of us (CKL). Voucher specimens (No. 20020914) have been depos-
ited at the Graduate Institute of Pharmacognosy, Taipei Medical
University, Taipei, Taiwan.
⇑
Corresponding authors. Tel.: +886 2 27361661x6150; fax: +886 2 23772265.
E-mail address: cklee@tmu.edu.tw (C.-K. Lee).
0
308-8146/$ - see front matter Crown Copyright Ó 2011 Published by Elsevier Ltd. All rights reserved.
doi:10.1016/j.foodchem.2011.11.067

9
22
T.-H. Lee et al. / Food Chemistry 132 (2012) 921–924
1
16
millilitre was collected for each fraction and each was analysed
by TLC. Then, each fraction was concentrated and re-dissolved in
2
4
R1
(CH )
17
2 8
a minimum volume of n-hexane–ethyl acetate mixture and used
#
R2
R3
in the subsequent HPLC system. Fr. 8 eluted by n-hexane–ethyl
acetate (1:1), was purified by a semi-preparative HPLC (Phenome-
nex Luna silica 5
4:1) as eluent at a flow rate of 3 ml/min to afford 1 (98 mg,
= 8.1 min), 2 (375 mg, t = 9.3 min), 3 (69 mg, t = 10.6 min), 4
74 mg, t = 11.9 min), 5 (64 mg, t = 15.1 min) and 6 (126 mg,
= 12.8 min). The same fraction was purified by the same column
using n-hexane–ethyl acetate–acetone (7:2:1) as eluent at a flow
rate of 3 ml/min to obtain 7 (154 mg, t = 16.2 min), 8 (94 mg,
= 20.1 min) and 9 (56 mg, t = 34.7 min). Fr. 21, eluted by ace-
l
m, 10 ꢀ 250 mm), using n-hexane–ethyl acetate
R1
OAc
OH
OAc
OAc
OH
R2
OAc
OAc
OH
OH
OH
R3
OH
OAc
OAc
OH
OAc
OH
(
1
t
R
R
R
2
5
7
8
9
(
R
R
t
R
R
OH
OH
#
t
R
R
tone, was purified by the same column, using n-hexane–acetone
(5:1) as eluent at a flow rate of 3 ml/min to yield 10 (134 mg,
1
2
4
16
t
R
R
= 10.4 min) and 11 (153 mg, t = 13.5 min).
R1
(CH )
2 7
1
oil; ½
,2R-Diacetoxy-4R-hydroxy-n-heptadeca-16-ene (1): colourless
17
2
2
R2
R3
a
ꢁ
D
3
+1.1 (c 1.0, CHCl ); IR (neat) mmax 3399, 1738; positive FAB-
+
+
MS m/z 371 [M+H] ; HRFABMS m/z 371.2798 [M+H] (calcd for
1
13
C
21
H
39
O
5
, 371.2798); for H and C NMR data see Tables 1 and 2.
R1
R2
OAc
OAc
OH
OH
OH
R3
OH
OAc
OAc
OH
2
R,4R-Diacetoxy-1-hydroxy-n-heptadeca-16-ene (2): colourless
3
4
6
1
1
OAc
OH
OAc
OAc
OH
2
2
oil; ½
aꢁ
ꢂ0.81 (c 1.0, CHCl
3
); IR (neat)
mmax 3392, 1731; FABMS m/z
D
+
+
3
3
71 [M+H] ; HRFABMS m/z 371.2794 [M+H] (calcd for C21H O ,
39 5
1
13
71.2798); for H and C NMR data see Tables 1 and 2.
,2R-Diacetoxy-4R-hydroxy-n-heptadeca-16-yne (3): colourless
0
1
1
oil; ½
OH
2
2
aꢁ
D
3
+5.7 (c 1.5, CHCl ); IR (neat) mmax 3396, 2100, 1735; FABMS
+
+
Fig. 1. Structures of compounds 1–11 isolated from the leaves of Persea americana.
m/z 369 [M+H] ; HRFABMS m/z 369.2638 [M+H] (calcd for
1
13
C
21
H
37
O
5
, 369.2641); for H and C NMR data see Tables 1 and 2.
2
oil; ½
R,4R-Diacetoxy-1-hydroxy-n-heptadeca-16-yne (4): colourless
2
2
2
.4. Extraction and isolation
aꢁ
D
3
+4.0 (c 1.0, CHCl ); IR (neat) mmax 3466, 2116, 1736; FABMS
+
+
m/z 369 [M+H] ; HRFABMS m/z 369.2639 [M+H] (calcd for
1
13
Fresh leaves (20.4 kg) of P. americana were extracted three
21 37 5
C H O , 369.2641); for H and C NMR data see Tables 1 and 2.
times with 100 l of acetone, which was filtered and evaporated
to give a black residue (1096 g). This residue was then suspended
2
.5. Acetonide derivative of 1
in H
and the n-hexane layer was evaporated to dryness under vacuum
345 g). Subsequently, the dried n-hexane layer was mixed with
96 g of silica gel, and was loaded onto a conditioned open column
2
O (3.0 l) and partitioned with equal volume of n-hexane,
3
To a solution of compound 1 (6.0 mg), in anhydrous CH CN, was
added CH ONa (12 mg) in one portion at room temperature. After
3
completion of the deacetylation, the resulting triol compound 9
and 2,2-dimethoxypropane were then dissolved in anhydrous
(
3
packed with 2458 g of silica gel and eluted, in a step-wise gradient,
by mixtures of n-hexane, ethyl acetate and acetone. Five hundred
2 2
CH Cl and treated with an amount of p-toluenesulfonic acid
monohydrate, as catalyst, as described in the literature Kashman,
Néeman, and Lifshitz (1970). After starting material was con-
sumed, monitored by TLC, the reaction mixture was neutralised
with Et N and then the solvent was removed to afford a 2,4-O-iso-
3
propylidene derivative 12 (3.6 mg).
Table 1
1
3C NMR (125 MHz) spectroscopic data for compounds 1–4 (in CDCl
3
, d in ppm).
No.
1a
2a
3a
4a
1
2
3
4
5
6
7
8
9
1
1
1
1
1
1
1
1
65.0 t
70.1 d
38.1 t
69.1 d
37.8 t
25.4 t
29.7 t
29.6 t
29.6 t
29.5 t
29.5 t
29.4 t
29.1 t
28.9 t
33.8 t
139.3 d
114.1 t
170.6 s
21.2 q
170.8 s
20.8 q
64.2 t
71.1 d
34.8 t
72.4 d
34.3 t
25.1 t
31.6 t
29.7 t
29.6 t
29.5 t
29.4 t
29.3 t
29.1 t
28.9 t
33.8 t
139.3 d
114.1 t
64.9 t
70.1 d
38.0 t
68.9 d
34.3 t
25.2 t
29.6 t
29.5 t
29.5 t
29.4 t
29.4 t
29.0 t
28.7 t
28.4 t
18.3 t
68.0 s
84.8 d
171.0 s
21.3 q
171.1 s
20.8 q
64.0 t
71.2 d
34.8 t
72.0 d
34.2 t
25.1 t
29.4 t
29.3 t
29.2 t
29.2 t
28.9 t
28.7 t
28.6 t
28.3 t
18.4 t
67.9 s
84.8 d
2.6. Chemical quantification by a MRM mode of LC–MS–MS
Fresh leaves, immature fruits, mature fruits and seeds (each
2
5 g) were extracted ultrasonically with acetone (3 ꢀ 250 ml). The
extracts were pooled and filtered through a 0.22 m nylon mem-
brane before injection for LC–MS–MS analyses. LC was performed
m particle,
l
with an HPLC (Agilent 1100), using a 4.6 ꢀ 250 mm, 5
l
0
1
2
3
4
5
6
7
Biosil Aqu-ODS-W column (Biotic Chemical Co., Ltd., Taiwan) at a
flow rate of 0.8 ml/min. The mobile phase was started at 100%
H
2
O, then changed to 100% MeOH in 30 min, and maintained at
100% MeOH for 20 min. Mass spectrometry was performed with a
000Q TRAP (Applied Biosystem) equipped with an ESI probe and
4
a tandem quadrupole analyser. Quantification was performed in
MRM mode, and the ion transitions are listed in Table 3.
CH
CH
CH
CH
CH
3
COO-1
COO-1
3
3
COO-2
179.8 s
22.6 q
170.9 s
21.2 q
170.8 s
21.1 q
170.9 s
21.2 q
3. Results and discussion
3
COO-2
3
COO-4
An acetone extract of the leaves of P. americana was partitioned in
a preliminary manner to give an n-hexane-soluble layer. Gravity col-
umn separation of this layer, over silica gel, followed by HPLC
CH
3
COO-4
a
Multiplicities were obtained from DEPT experiments.

T.-H. Lee et al. / Food Chemistry 132 (2012) 921–924
923
Table 2
1
H NMR (500 MHz) spectroscopic data for compounds 1–4 (in CDCl
3
, d in ppm, J in Hz).
No.
1
1
2
3
4
4.09 (dd, 12.0, 6.4)
4
5.21 (m)
1.72 (t, 6.5)
3.67 (m)
1.42 (m)
1.23 (m)
1.23 (m)
1.23 (m)
1.23 (m)
1.23 (m)
1.23 (m)
1.23 (m)
1.23 (m)
1.34 (m)
2.01 (m)
5.78 (ddt, 17.0, 10.1, 6.6)
4.96 (dd, 17.0, 1.2)
3.64 (dd, 12.1, 5.5)
4.08 (dd, 12.1, 6.5)
4.26 (dd, 12.1, 3.1)
5.21 (m)
1.71 (t, 6.6)
3.67 (m)
1.41 (m)
1.23 (m)
1.23 (m)
1.23 (m)
1.23 (m)
1.23 (m)
1.23 (m)
1.23 (m)
1.35 (m)
1.48 (m)
2.14 (td, 7.1, 2.7)
3.64 (dd, 12.1, 5.7)
3.73 (dd, 12.1, 3.4)
4.92 (m)
1.87 (t, 6.4)
4.94 (m)
1.52 (m)
1.23 (m)
1.23 (m)
1.23 (m)
1.23 (m)
1.23 (m)
1.23 (m)
1.23 (m)
1.36 (m)
1.51 (m)
2.16 (td, 6.9, 2.5)
.26 (dd, 12.0, 3.1)
3.72 (dd, 12.1, 3.5)
4.92 (m)
1.87 (t, 6.4)
4.94 (m)
1.53 (m)
1.24 (m)
1.24 (m)
1.24 (m)
1.24 (m)
1.24 (m)
1.24 (m)
1.24 (m)
1.24 (m)
1.35 (m)
2.01 (m)
5.79 (m)
4.91 (m)
4.97 (m)
2
3
4
5
6
7
8
9
1
1
1
1
1
1
1
1
0
1
2
3
4
5
6
7
1.90 (t, 2.7)
1.91 (t, 2.5)
4
.89 (dd, 10.1, 1.2)
CH
3
CH
3
CH
3
COO-1
COO-2
COO-4
2.03 (s)
2.03 (s)
2.03 (s)
2.03 (s)
2.03 (s)
2.06 (s)
2.03 (s)
2.06 (s)
Table 3
70-7 and 1174388-00-1, respectively, were shown in the SciFinder
database (Chemical Abstracts Service, USA).
The ratios of the contents of 1–3 and 4–6 in leaves, immature fruits, mature fruits and
seeds of P. americana.
Compound 1 was obtained as a colourless oil and its IR
Parts of P. americana
1–3a,c
4–6b,c
absorptions at 3399 and 1738 cm indicated the presence of a
ꢂ1
Leaves
65.6
93.8
50.0
46.9
6.3
8.8
1.0
4.1
hydroxy and an acetoxy carbonyl functionality, respectively.
Twenty-one carbon resonances, attributed to two quaternary car-
bons (CH COO-1 and CH COO-2), one oxymethylene (C-1), two
3 3
carbinoyl methines (C-2 and C-4), one olefinic methine (C-16),
one exomethylene (C-17) and twelve methylenes (C-3, C-5 and
Immature fruits
Mature fruits
Seeds
a
The ratios were estimated from the peak height at R
chromatogram. The ion transitions for 1–3 are 371?311 (de-acetyl) and 371?251
de-diacetyl).
The ratios were estimated from the peak height at R
chromatogram. The ion transitions for 4–6 are 369?309 (de-acetyl) and 369?247
de-diacetyl).
t
29.6 min in the LC–MS
C-6–C-15), and two methyls (CH
3
COO-1 and CH
served in the C NMR spectrum coupled with the DEPT spectrum
of 1 (Table 1). On account of the molecular formula, C21 , as
3
COO-2) were ob-
(
13
b
t
28.2 min in the LC–MS
38 5
H O
(
assigned by HREIMS, the double bond equivalence (DBE) of 1 was
determined to be three, consistent with two acetoxy carbonyl
groups and one olefinic functionality, which were further sup-
c
All the ratios of the contents were calculated from the peak height of com-
pounds in each material over the peak height of 4–6 in mature fruits.
ported by two carbonyl signals at d
C
170.6 (CH
3
COO-1) and
139.3
1
70.8 (CH COO-2) and one pair of olefinic carbons at d
3
C
1
3
purification, afforded four previously unreported heptadecanols
(C-16)/114.1 (C-17) in the C NMR spectrum of 1. The above
assignments were characteristic for a linear aliphatic skeleton
bearing one hydroxy, two acetoxys and one double bond. The
(
1–4), along with seven known compounds. The known compounds
were identified as 1-acetoxy-2R,4R-dihydroxy-n-heptadec-16-ene
7) (Domergue et al., 2000), 4-acetoxy-1R,2R-dihydroxy-n-hepta-
1
(
connectivity of 1 was further deduced by its H NMR (Table 2)
dec-16-ene (8) (Domergue et al., 2000), 1,2R,4R-trihydroxy-n-hep-
tadec-16-ene (9) (Oberlies et al., 1998), 1-acetoxy-2R,
and selected COSY [d
(H-2)/d 1.72 (H -3); d
16)/d 4.96, 4.89 (H -17)] and key HMBC (H
H-2/CH COO-2) correlations (Fig. 2). The relative configurations
of carbinoyl H-2 and H-4 of 1 were deduced to be both axial-ori-
H
4.09, 4.26 (H
2
-1)/d
3.67 (H-4); d
-1/CH COO-1 and
H
5.21 (H-2); d
H
5.21
H
2
H
1.72 (H -3)/d
2
H
H
5.78 (H-
4
R-dihydroxy-n-heptadec-16-yne (10) (Domergue et al., 2000),
and 1,2R,4R-trihydroxy-n-heptadec-16-yne (11) (Oberlies et al.,
998). Although 1,4R-diacetoxy-2R-hydroxy-n-heptadeca-16-ene
5) and 1,4R-diacetoxy-2R-hydroxy-n-heptadec-16-yne (6) were
H
2
2
3
3
1
(
⁄
⁄
ented (both R or S ) by the JH-2/H-3ax (12.0 Hz), JH-4/H-3ax (12.0 Hz)
and NOESY assignments (Fig. 3) of its acetonide derivative, 12.
well-known compounds, only registered CAS numbers 1083200-
O
1
1
7
2
4
O
16
O
OH
O
Selected COSY
Selected HMBC
Fig. 2. Selected COSY and HMBC of 1.

9
24
T.-H. Lee et al. / Food Chemistry 132 (2012) 921–924
this study, all the pure isolates 1–11 were evaluated for their bio-
logical activities, including vasodilating, DPPH-scavenging, anti-
xanthine oxidase and anti-tyrosinase. However, they exhibited no
significant activity, even at concentrations higher than 100 lM.
Acknowledgments
We are grateful to Ms. Shwu-Huey Wang, Ms. Shou-Ling Huang
and Ms. Shu-Yun Sun of the Instrumentation Center of Taipei Med-
ical University and the Instrumentation Center of the College of
Science, National Taiwan University, respectively, for the NMR
and MS data acquisition. We also wish to thank the National Sci-
ence Council and Center of Excellence for Clinical Trial and Re-
search in Neuroscience, WanFang Hospital for their financial
support.
Fig. 3. Selected NOESY of 12.
The absolute configurations of C-2 and C-4 were further con-
firmed to be both R based on comparison of the optical rotation
2
D
2
value ½
mers ([
tadecanol) in the literature Sugriyama, Sato, and Yamashita
1982). Accordingly, 1 was characterised as shown, and was
a
a
ꢁ
ꢂ8.3 (c 1.0, CHCl
3
) of 9 with the configurational iso-
]
D
ꢂ6.4 for 2R,4R-heptadecanol; [ +6.0 for 2S,4S-hep-
a]
D
References
(
Adeyemi, O. O., Okpo, S. O., & Ogunti, O. O. (2002). Analgesic and anti-inflammatory
effects of the aqueous extract of leaves of Persea americana Mill (Lauraceae).
Fitoterapia, 73, 375–380.
Adikaram, N. K. B., Ewing, D. F., Karunaratne, A. M., & Wijeratne, E. M. K. (1992).
Antifungal compounds from immature avocado fruit peel. Phytochemistry, 31,
named as 1,2R-diacetoxy-4R-hydroxy-n-heptadeca-16-ene.
All the physical data of 2 closely resemble those of 1, indicating
that 2 was the isomer of 1. The major differences involved were
only the locations of the acetoxy functionalities, as evidenced from
the HMBC spectrum of 2. Cross peaks of H-2/CH
CH COO-4 in the HMBC spectrum of 2, corroborating the acetoxy
moieties, were located at C-2 and C-4 of 2. Thus, the structure of
was determined to be as shown, and was named as 2R,4R-diacet-
93–96.
3
COO-2 and H-4/
Chiu, N. Y., & Chang, K. H. (Eds.). (1998). The illustrated medicinal plants of Taiwan
(Vol. 2, pp. 79). Taipei: SMC Publishing Inc.
Chenga, M. J., Jayaprakasama, B., Ishikawab, T., Sekic, H., Tsaia, L., Wang, J. J., et al.
3
(
2002). Chemical and cytotoxic constituents from the stem of Machius
2
zuihoensis. Helvetica Chimica Acta, 85, 1909–1914.
oxy-1-hydroxy-n-heptadeca-16-ene.
Domergue, F., Helms, G. L., Prusky, D., & Browse, J. (2000). Antifungal compounds
from idioblast cells isolated from avocado fruits. Phytochemistry, 54, 183–189.
Gross, J., Gabai, M., Lifshitz, A., & Sklarz, B. (1974). Structures of some carotenoids
from the pulp of Persea americana. Phytochemistry, 13, 1917–1921.
Hashimura, H., Ueda, C., Kawabata, J., & Kasai, T. (2001). Acetyl-CoA carboxylase
inhibitors from avocado (Persea americana Mill) fruits. Bioscience Biotechnology
Biochemistry, 65, 183–189.
Huang, T. T. (2004). Studies on the constituents of the leaves of Persea americana var.
americana. Master thesis of Graduate Institute of Pharmacognosy, Taipei
Medical University, Taipei, Taiwan.
Compounds 3 and 4 also possessed skeletons identical to those
of 1 and 2, respectively, except that their H-16 was absent and H-
1
7 up-field shifted to around d
H
1.90 in the 1H NMR spectra of 3
16
and 4. This difference unambiguously indicated that a
and 2, was replaced by an acetylenic moiety in 3 and 4, which
was also reflected in their IR absorptions of 2100 and 2116 cm
D
, in both
1
ꢂ1
,
respectively. Conclusively, 3 and 4 were identified as shown, and
were named as 1,2R-diacetoxy-4R-hydroxy-n-heptadeca-16-yne
and 2R,4R-diacetoxy-1-hydroxy-n-heptadeca-16-yne, respectively.
Aliphatic alcohols with odd carbons are rarely found in higher
plants. To our knowledge, heptadecane with 1,2,4-trihydroxy
groups, such as 1–11 have been found only in Persea spp. so far. It
was found that the pure isolates 1–3 and 4–6 were prone to inter-
convert into respective mixtures of 1–3 and 4–6 when they were dis-
solved in CHCl with slight acidity. The interconversion to their
3
respective mixtures was speculated to be caused by the migration
of the acetyl moieties.
The ratios of the contents of heptadecanols with a terminal dou-
ble bond, including 1–3, and heptadecanols with a terminal triple
bond, including 4–6 in leaves, immature fruits, mature fruits and
seeds of P. americana were estimated by a LC system coupled with
tandem MS in multiple reaction monitoring (MRM) mode (Table 3).
It was found that the contents of 1–3 were at least tenfold those of
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A2 and its derivatives. Journal of Chemical Society Perkin Transactions, 1,
2663–2671.
Karikome, H., Mimaki, Y., & Sashida, Y. (1991). A butanolide and phenolics from
Machilus thunbergii. Phytochemistry, 30, 315–319.
Kashman, Y., Néeman, I., & Lifshitz, A. (1970). New compounds from avocado pear II.
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Kawagishi, H., Fukumoto, Y., Hatakeyama, M., He, P., Arimoto, H., Matsuzawa, T.,
et al. (2001). Liver injury suppressing compounds from avocado (Persea
americana). Journal of Agricultural and Food Chemistry, 49, 2215–2221.
Kim, O. K., Murakami, A., Nakamura, Y., Takeda, N., Yoshizumi, H., & Ohigashi, H.
(2000). Novel nitric oxide and superoxide generation inhibitors, persenone A
and B, from avocado fruit. Journal of Agricultural and Food Chemistry, 48,
1557–1563.
Komae, H., & Hayashi, N. (1972). Terpenes from actinodaphne, Machilus thunbergii.
Phytochemistry, 11, 1181–1182.
Oberlies, N. H., Rogers, L. L., Martin, J. M., & Mclaughlin, J. L. (1998). Cytotoxic and
insecticidal constituents of the unripe fruit of Persea Americana. Journal of
Natural Products, 61, 781–785.
Prusky, D., Keen, N. T., Sims, J. J., & Midland, S. L. (1982). Possible involvement of an
antifungal diene in the latency of Colletotricum gloeosporioides on unripe
avocado fruits. Phytopathology, 72, 1578–1582.
Prusky, D., Kobiler, I., Fishman, Y., Sims, J., Midland, S. L., & Keen, N. T. (1991).
Identification of an antifungal compound in unripe avocado fruits and its
possible involvement in the quiescent infections of Colletotrichum
gloeosporioides. Journal of Phytopathology, 132, 319–327.
Sugriyama, T., Sato, A., & Yamashita, K. (1982). Synthesis of all four stereoisomers of
antibacterial component of avocado. Agricultural and Biological Chemistry, 46,
481–485.
Tomita, M., Lu, S. T., & Lan, P. K. (1965). Alkaloids of the several Machilus genus
plants. Chemical Abstracts, 63, 12005.
4
–6 in four parts of P. americana. The total contents of 1–6 in
immature fruits were estimated to be higher than those in the
other three parts of P. americana.
Heptadecanols isolated from avocado have never been reported
to exhibit cytotoxic (Oberlies et al., 1998), insecticidal (Oberlies
et al., 1998), anti-fungal (Adikaram et al., 1992; Domergue et al.,
2
000), liver injury-suppressing (Kawagishi et al., 2001) or acetyl-
CoA carboxylase inhibitory (Hashimura et al., 2001) activities. In