ArticlePDF Available

East Indian Sandalwood and α-Santalol Odor Increase Physiological and Self-Rated Arousal in Humans

Authors:
  • Self-employed

Abstract and Figures

In Ayurvedic medicine, East Indian Sandalwood is an important remedy for the treatment of both somatic and mental disorders. In this investigation, the effects of inhalation of East Indian Sandalwood essential oil and its main compound, alpha-santalol, on human physiological parameters (blood oxygen saturation, respiration rate, eye-blink rate, pulse rate, skin conductance, skin temperature, surface electromyogram, and blood pressure) and self-ratings of arousal (alertness, attentiveness, calmness, mood, relaxation and vigor) were studied in healthy volunteers. Compared to either an odorless placebo or alpha-santalol, Sandalwood oil elevated pulse rate, skin conductance level, and systolic blood pressure. alpha-Santalol, however, elicited higher ratings of attentiveness and mood than did Sandalwood oil or the placebo. Correlation analyses revealed that these effects are mainly due to perceived odor quality. The results suggest a relation between differences in perceived odor quality and differences in arousal level.
Content may be subject to copyright.
Introduction
The essential oil of East Indian Sandalwood (Santalum album L.,
Santalaceae) contains more than 90% of sesquiterpenic alcohols,
the santalols. The major component, with approximately 50±
60 %, among these alcohols is the tricyclic
a
-santalol.
b
-Santalol
makes up for about 20±25 % [1]. In traditional Oriental medicine
it is utilized for the treatment of various somatic disorders and
psychic syndromes. Recently, Sandalwood oil and
a
-santalol have
been associated with chemopreventive activity in animal models
of carcinogenesis [2], [3], [4]. In addition, antiviral [5], [6] and an-
ticandidal effects of Sandalwood oil [7] have been demonstrated.
It has long been observed that inhalation of essential oils may
cause physiological and behavioral changes in humans [8]. Clini-
cal evidence in aromatherapy suggests that beneficial effects are
also exerted by application of fragrances to the skin. It is assumed
that the effects of fragrances are elicited by psychological and
pharmacological mechanisms, i. e., via the sense of smell and
due to the uptake of fragrance molecules into the organism [9].
In aromatherapy, Sandalwood oil is deemed aphrodisiac, antide-
pressant, relaxing, and sedative. Buchbauer et al. [10] reported
that exposure to Sandalwood vapor reduced the motility of
mice. Recent investigations [11], [12] have shown that inhalation
of as well as massage with Sandalwood oil have an excellent
East Indian Sandalwood and
aa
-Santalol Odor Increase
Physiological and Self-Rated Arousal in Humans
Eva Heuberger
1, 2
Tapanee Hongratanaworakit
3
Gerhard Buchbauer
1
Affiliation
1
Department of Clinical Pharmacy and Diagnostics, Faculty of Life Sciences, University of Vienna, Vienna,
Austria
2
Smell and Taste Center, Department of Otorhinolaryngology ± Head and Neck Surgery, School of Medicine,
University of Pennsylvania, Philadelphia, USA
3
Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Srinakharinwirot University, Nakorn-nayok,
Thailand
Correspondence
Dr. Eva Heuberger ´ Department of Clinical Pharmacy and Diagnostics ´ University of Vienna ´ Althanstr. 14 ´
1090 Vienna ´ Austria ´ Phone: +43-1-4277-55560 ´ Fax: +43-1-4277-9555 ´
E-mail: eva.heuberger@univie.ac.at
Received January 20, 2006 ´ Accepted April 25, 2006
Bibliography
Planta Med 2006; 72: 792±800 Georg Thieme Verlag KG Stuttgart ´ New York
DOI 10.1055/s-2006-941544 ´ Published online June 19, 2006
ISSN 0032-0943
Abstract
In Ayurvedic medicine, East Indian Sandalwood is an important
remedy for the treatment of both somatic and mental disorders.
In this investigation, the effects of inhalation of East Indian San-
dalwood essential oil and its main compound,
a
-santalol, on hu-
man physiological parameters (blood oxygen saturation, respira-
tion rate, eye-blink rate, pulse rate, skin conductance, skin tem-
perature, surface electromyogram, and blood pressure) and self-
ratings of arousal (alertness, attentiveness, calmness, mood,
relaxation and vigor) were studied in healthy volunteers. Com-
pared to either an odorless placebo or
a
-santalol, Sandalwood
oil elevated pulse rate, skin conductance level, and systolic blood
pressure.
a
-Santalol, however, elicited higher ratings of atten-
tiveness and mood than did Sandalwood oil or the placebo. Cor-
relation analyses revealed that these effects are mainly due to
perceived odor quality. The results suggest a relation between
differences in perceived odor quality and differences in arousal
level.
Key words
Arousal ´ East Indian Sandalwood oil ´
a
-santalol ´ inhalation ´
physiological monitoring ´ odor quality
Original Paper
792
Downloaded by: Saarländische Universitäts- u. Landesbibliothek. Copyrighted material.
sleep-inducing effect on rats and mice which might be triggered
by
a
- and
b
-santalol since these alcohols have proven to be neu-
roleptic agents with a similar pharmacological activity as chlor-
promazine [13]. After percutaneous absorption, deactivating ef-
fects of East Indian Sandalwood oil and
a
-santalol were demon-
strated on human physiological and behavioral measures [14].
However, it remains to be shown whether these effects are also
elicited in humans when these fragrances are inhaled.
Therefore, in the present study the effects of inhalation of East
Indian Sandalwood oil and
a
-santalol on parameters of the peri-
pheral nervous system as well as on subjective feelings of arousal
were investigated. We aimed at assessing the impact of these
odors on the level of physiological arousal and on subjective
behavioral activation of healthy human subjects and at elucidat-
ing the mechanisms underlying these effects.
Materials and Methods
East Indian Sandalwood essential oil (SEO) and
a
-santalol were
used as fragrances in this study.
a
-Santalol was preferred over
b
-santalol since, from a pharmacodynamic viewpoint, we ex-
pected it to be the most effective constituent among the santa-
lols. SEO was obtained from Dragoco GmbH, Vienna, Austria
(product No. 16589). A voucher specimen (No. 4/942130) is
stored at 48C at the Department of Clinical Pharmacy and Diag-
nostics.
a
-Santalol was separated and isolated as described in [14].
SEO (containing 41.1 %
a
-santalol, [15]),
a
-santalol (GC-MS pur-
ity), and a placebo substance, i. e., odorless water, were adminis-
tered via a fragrance delivery system developed by our group.
The apparatus consists of an air tank, a drug nebulization device
(Inhalette
; Dräger; Vienna, Austria) and a breathing mask (B+P
Beatmungsprodukte GmbH; Neunkirchen, Germany). The nebu-
lizer was filled with 250 mg of fragrance or water and attached to
the system so that air (12 L/min) streamed over the surface of the
substance in the nebulizer. The so generated vapors were direct-
ed to the breathing mask and inhaled by the subject. All sub-
stances were administered to the subjects throughout 20 min-
utes. The amount of SEO and
a
-santalol, respectively, which had
evaporated during this period (ªconsumptionº), was calculated
by subtracting the mass of the nebulizer after inhalation from
the mass before inhalation.
Thirty-six young, healthy human subjects (18 males and 18 fe-
males; mean age 23.77  2.73 years) who were recruited by ad-
vertisement at the University of Vienna and paid for their parti-
cipation were randomly assigned to a control group or one of 2
experimental groups, i.e., the SEO group or the
a
-santalol group.
Finally, each group consisted of 12 subjects (6 males and 6 fe-
males). At 48 hours prior to testing subjects had to abstain from
food, beverages and toiletries containing SEO or santalols, as well
as from tea, coffee, and alcohol. Subjects gave written informed
consent to all aspects of the study (Viennese ethic commission's
permissions No. 324/96, 419/98) and were free to withdraw at
any time.
Subjects were tested in individual sessions. One session consist-
ed of two trials of 20 minutes. At the beginning as well as at the
end of each trial, subjective feelings of arousal, i. e., relaxation,
vigor, calmness, attentiveness, mood, and alertness, were asses-
sed by means of visual analogue scales (VAS). Subjective ratings
of the odor of the substance presented, i.e., pleasantness, inten-
sity, and effect, were measured on a VAS at the end of each trial.
Seven physiological parameters, i. e., blood oxygen saturation
(BOS), eye-blinks (EB), pulse rate (PR), respiration rate (RR), skin
conductance (SC), skin temperature (ST), and surface electro-
myogram (EMG), were recorded continuously during each trial
using MP100WSW hardware (Biopac Systems, Inc.; Santa Bar-
bara, CA, USA) and AcqKnowledge
software (V3.2.6, 1992±
1997; Biopac Systems, Inc.; Santa Barbara, CA, USA). In addition,
systolic (SBP) and diastolic blood pressure (DBP) were measured
at the beginning as well as at the end of each trial. Details on the
recording equipment, electrode positioning, and VAS are given
elsewhere [16], [17]. In the first trial, which served as an individ-
ual baseline, odorless water was administered to all subjects. In
the second trial, subjects in the control group again received the
placebo, whereas the appropriate fragrance was administered in
the experimental groups.
Procedure
The experiments were carried out in a bright and quiet room.
Ambient temperature was 21 ± 24 8C. Subjects were seated in a
semi-reclined position. They were told that a fragrance would
be presented, but were unaware of the kind of fragrance and the
exact time of administration.
All subjects were interviewed about their name, age, weight and
height, and about their dominant hand by means of the Edin-
burgh Handedness Inventory [18]. After the proceedings had
been explained to them, subjects rated their feelings of arousal
on the VAS. Subsequently, SBP and DBP were measured. Electro-
des were attached at suitable positions. The breathing mask was
fixed to the subject's face, comfortably covering nose and mouth
and allowing unhindered respiration. Subsequently, recording of
the physiological parameters was started. After completion of
the first trial subjects were allowed to remove the breathing
mask and VAS for subjective arousal and odor ratings were pres-
ented. SBP and DBP were measured at the end of the first trial. In
the second trial, which followed consecutively after the first trial,
this procedure was repeated.
Data reduction
The physiological recordings of each subject were computed
using AcqKnowledge
software. Mean values of ST, level of SC
(SCL), PR, and BOS within each trial were obtained for each sub-
ject. Mean values of RR and eye-blink rate (EBR) were deter-
mined by counting the number of inspirations and EB per min-
ute, respectively, and calculating the arithmetic mean for each
trial. The raw EMG signals were converted to the root-mean-
square (rms) values, and mean rms values were obtained. For
every subject and every parameter the mean value in the second
trial was subtracted from the mean value in the first trial. Differ-
ences between blood pressure measurements 2 and 4, and 3 and
4, respectively, were calculated for each subject.
Feelings of arousal as well as fragrance ratings were processed by
measuring the distance of the mark from the left-hand side in
mm on each scale. Individual differences between the second
Heuberger E et al. East Indian Sandalwood ¼ Planta Med 2006; 72: 792 ± 800
Original Paper
793
Downloaded by: Saarländische Universitäts- u. Landesbibliothek. Copyrighted material.
rating and the fourth rating as well as between the third rating
and the fourth rating were calculated for each item. For the fra-
grance ratings, individual differences between the first and the
second rating were computed.
Statistical analysis
Systat 9.0 (SPSS Inc., 1999) was used for statistical analyses. The
effects of SEO and
a
-santalol on the physiological parameters
and feelings of arousal were determined by comparing the differ-
ences between the control group and the experimental groups by
means of Mann-Whitney-U-Test and Kruskal-Wallis one-way
analysis of variance. Furthermore, the differences of the SEO
group were compared to those of the
a
-santalol group in order
to detect differences in the effectiveness of the fragrances.
To test for the overall influence of the fragrances on the physiol-
ogical arousal level, the 11 two-sided probabilities P resulting
from the univariate between-group comparisons were combined
by means of the transformation given below [19, pp. 46 ± 55], and
the resulting
c
2
-value was tested for significance:
The same analysis was performed on the 12 univariate between-
group comparisons of the parameters of subjective arousal to de-
termine the effectiveness of SEO and
a
-santalol at the behavioral
arousal level.
Spearman rank order correlation analyses were performed
within each group on the inter-trial differences of the physiol-
ogical parameters, the differences of SBP and DBP between the
second and the fourth measurement, the differences between
the second and the fourth rating of subjective arousal, and the
differences between the first and the second odor rating. With a
sample size of N = 12, Spearman's
|0.591| is considered sta-
tistically significant at the 0.05 level [19, p. 749]. Correlations be-
tween the consumption of fragrance and physiological para-
meter differences in the experimental groups were tested with
the Bravais-Pearson product moment correlation. Significant
correlations were inspected visually for outliers which might ac-
count for statistical significance.
Results
In Table 1, medians and mean inter-quartile ranges (MIQR) of the
physiological parameters in the first and the second trial as well
as of the self-ratings of arousal on the second, the third and the
forth rating are presented for all groups. Medians and MIQR of
the inter-trial differences of EBR and PR are depicted in Fig. 1.
Univariate comparisons of the physiological parameters showed
a trend toward an increase of EBR in the SEO group compared
with the control group (U = 72.0, P = 0.064). Comparison of the
inter-trial differences of PR revealed a significant increase of PR in
the SEO group compared to both the control group (U = 114.0,
P =0.000)andthe
a
-santalol group (U = 15.0, P =0.003).
Medians and MIQR of the inter-trial differences of ST and SCL are
shown in Fig. 2. Comparison of the inter-trial differences of ST re-
vealed a trend toward a decrease of ST in the second trial in the
SEO group compared with the control group (U = 40.0,
P = 0.065). A significant decrease of ST in the
a
-santalol group
compared to the control group (U = 38.0, P = 0.050) was ob-
served. Comparison of the inter-trial differences of SCL showed
a significant increase of SCL in the second trial in the SEO group
compared with both the control group (U = 91.0, P = 0.011) and
the
a
-santalol group (U = 20.0, P = 0.008).
Medians and MIQR of SBP and DBP differences between the sec-
ond and the fourth measurement (difference 2± 4) and between
the third and the fourth measurement (difference 3 ± 4) are
shown in Fig. 3. SBP significantly decreased in the
a
-santalol
group compared to the SEO group on the fourth in relation to
the third measurement (U = 38.0, P = 0.048). Comparison of
DBP differences 2± 4 revealed a trend toward a smaller increase
in the SEO group than in both the control group (U = 42.0,
P = 0.081) and the
a
-santalol group (U = 104.0, P = 0.063).
Medians and MIQR of the differences of subjective attentiveness
and relaxation between the second and the fourth rating (differ-
ence 2 ±4) as well as between the third and the fourth rating (dif-
ference 3±4) are depicted in Fig. 4. Univariate comparisons of
the self-ratings of arousal indicated that subjective attentiveness
on rating 4 compared with rating 2 increased significantly more
in the
a
-santalol group than in the SEO group (U = 36.0,
P = 0.038). At the end of the second trial in relation to the begin-
ning of that trial, subjects in the SEO group felt marginally more
attentive than those in the control group (U = 41.5, P = 0.078).
Subjects in the
a
-santalol group rated themselves as significantly
more attentive than those in both the control group (U = 26.5,
P = 0.009) and the SEO group (U = 36.5, P = 0.040). Comparison
of the differences 2±4 revealed a trend toward a larger decrease
of subjective relaxation in the SEO group than in the control
group (U = 101.0, P = 0.094).
Medians and MIQR of the differences of subjective alertness and
mood between the second and the fourth rating (difference 2 ± 4)
as well as between the third and the fourth rating (difference 3 ±
4) are presented in Fig. 5. Comparison of the differences 2 ± 4
showed a weak trend toward a larger increase of subjective alert-
ness in the SEO group than in the
a
-santalol group (U = 100.5,
P = 0.100). A trend toward higher subjective alertness on rating
4 compared to rating 2 was found between the SEO group and
the control group (U = 42.0, P = 0.083). Comparison of the dif-
ferences 3± 4 revealed a significant increase of subjective mood
in the
a
-santalol group compared with the control group
(U = 34.0, P = 0.028).
No significant effects of the fragrances were found on BOS, RR,
EMG, subjective vigor, and calmness (P > 0.1 for all, data not
shown).
Comparison of the combined measures of physiological and
behavioral effects between the control group and the SEO group
resulted in a significant effect of SEO at the physiological level
(
c
2
= 51.859, df = 22, P < 0.001) and a trend toward significance
at the level of feelings of arousal (
c
2
= 33.714, df = 24, P < 0.1).
Comparison of the SEO group with the
a
-santalol group showed
significant differences at both the physiological and the behav-
Heuberger E et al. East Indian Sandalwood ¼ Planta Med 2006; 72: 792 ± 800
Original Paper
794
Downloaded by: Saarländische Universitäts- u. Landesbibliothek. Copyrighted material.
ioral level (
c
2
= 46.838, df = 22, P < 0.005;
c
2
= 36.909, df = 24,
P < 0.05). No overall effects were found for
a
-santalol compared
to the placebo substance (
c
2
= 17.802, df = 22, P >0.1;
c
2
= 29.632, df = 24, P > 0.1).
Medians and MIQR of subjective odor intensity and effect on the
first and second rating for the control group and the experimen-
tal groups are given in Table 1. Medians and MIQR of the differen-
ces of subjective odor intensity and effect are presented in Fig. 6.
In the experimental groups, the odor of the substance in the sec-
ond trial compared to water in the first trial was experienced as
significantly more intense than in the control group (SEO vs. con-
trol: U = 123.0, P = 0.003;
a
-santalol vs. control: U = 112.0,
P = 0.021). In addition, the odor intensity of SEO was rated sig-
nificantly higher than that of
a
-santalol (U = 32.0, P = 0.021).
Comparison of the effect differences showed a trend toward
higher ratings at the end of trial 2 in relation to the end of trial 1
in the SEO group than in the control group (U = 41.0, P = 0.073).
The ratings of odor pleasantness did not differ significantly be-
tween groups (P > 0.1, data not shown).
Mean mass and SEM of evaporated SEO and
a
-santalol are shown
in Fig. 7. The consumption of SEO was significantly higher than
that of
a
-santalol (t = 3.834, P = 0.001).
Significant correlations were observed in all groups. The less in-
tense water was rated at the end of the second trial, the more at-
tentive felt subjects in the control group (
r
= + 0.804); and the
more cheerful subjects felt at the end of the second trial, the
more rose BOS (
r
= -0.648).
The more stimulating subjects in the SEO group rated the odor in
the second trial, the more increased SCL (
r
= ±0.691) and the
more vigorous they felt in the second trial (
r
= + 0.615). Also,
the more vigorous subjects felt on rating 4, the more rose SCL
(
r
= ±0.642) and EBR in the second trial (
r
= ±0.547); the more
attentive subjects felt at the end of trial 2, the more increased PR
(
r
= ±0.717); the more restless subjects rated themselves, the
more rose EMG in the second trial (
r
= + 0.609); the more cheer-
ful subjects were on rating 4, the less increased RR (
r
= + 0.718);
and the higher the consumption of SEO was, the more cheerful
felt subjects (
r
= + 0.610) and the less increased RR
(r = + 0.605, P = 0.037).
Table 1 Medians and mean inter-quartile ranges (MIQR) of skin temperature (ST), skin conductance level (SCL), eye-blink rate (EBR), pulse rate
(PR), systolic blood pressure (SBP), subjective relaxation, subjective attentiveness, subjective mood, and subjective alertness for the
control group (C), the Sandalwood oil group (SEO) and the
a
-santalol group (S)
Median MIQR
C SEO S C SEO S
ST Trial 1 31.69 32.38 33.29 1.26 1.72 0.96
Trial 2 31.23 31.26 32.03 1.74 1.71 1.60
SCL Trial 1 2.51 2.34 3.93 0.93 0.85 1.13
Trial 2 3.13 4.20 3.77 1.09 0.79 1.97
EBR Trial 1 10.88 11.75 16.90 4.59 4.58 5.91
Trial 2 15.25 17.05 17.35 6.09 7.71 4.42
PR Trial 1 67.78 64.12 71.19 6.91 5.73 4.24
Trial 2 64.84 63.43 72.05 4.92 6.34 6.44
SBP Measurement 2 116.00 115.50 115.50 7.00 10.00 11.00
Measurement 3 118.50 118.50 113.50 6.00 10.25 13.25
Measurement 4 119.00 120.00 114.00 6.25 10.25 11.25
DBP Measurement 2 68.50 71.00 71.50 3.00 6.25 5.50
Measurement 3 68.50 67.50 73.00 4.00 6.25 8.00
Measurement 4 69.50 70.00 76.00 2.50 7.25 7.50
Relaxation Rating 2 9.50 14.25 20.25 8.75 6.00 11.50
Rating 3 11.75 16.75 18.00 5.63 5.63 5.50
Rating 4 18.50 30.00 21.75 11.13 11.88 15.63
Attentiveness Rating 2 49.00 29.75 31.25 10.75 9.00 21.25
Rating 3 25.50 23.25 27.00 18.63 9.38 15.63
Rating 4 41.50 25.25 19.75 15.13 6.50 9.88
Mood Rating 2 16.50 21.00 24.50 10.75 11.38 11.88
Rating 3 14.75 24.75 25.75 8.38 12.63 12.00
Rating 4 30.00 26.00 22.75 18.25 8.50 9.13
Alertness Rating 2 56.75 52.25 47.00 11.88 13.88 24.25
Rating 3 44.50 37.50 49.75 12.38 12.38 17.88
Rating 4 51.25 24.25 32.75 20.38 8.63 25.50
Intensity Rating 1 14.75 14.50 16.00 14.00 8.25 14.38
Rating 2 11.75 63.75 36.50 17.50 14.00 22.13
Effect Rating 1 66.00 58.25 55.00 10.25 12.75 12.63
Rating 2 55.25 33.00 36.25 9.25 11.63 16.13
Heuberger E et al. East Indian Sandalwood ¼ Planta Med 2006; 72: 792 ± 800
Original Paper
795
Downloaded by: Saarländische Universitäts- u. Landesbibliothek. Copyrighted material.
In the
a
-santalol group, the odor was rated the more stimulating,
the more attentive (
r
= + 0.677) and alert subjects felt at the end
of trial 2 (
r
= + 0.706); the more pleasant the odor was judged
on the second rating, the more cheerful felt subjects
(
r
= + 0.683); the lower the consumption of
a
-santalol was, the
more cheerful (
r
= ±0.729) felt subjects on the fourth rating and
the more pleasant they judged the odor (
r
= ±0.791).
Discussion
In our study, inhalation of Sandalwood oil, compared to odorless
water, increased ANS arousal, specifically pulse rate and skin
conductance level, in healthy human subjects. In contrast, the
test for effects on overall self-rated arousal failed to reach statis-
tical significance. Inhalation of
a
-santalol, compared to odorless
Fig. 2 Medians and mean inter-quartile
ranges of skin temperature and skin conduc-
tance level differences for the control group
and the experimental groups (Sandalwood
oil and santalol); H on the top of the bars in-
dicates significant differences (P
£
0.050)
between the control group and the experi-
mental groups, * on top of the bars indi-
cates significant differences (P
£
0.050) be-
tween the experimental groups.
Fig. 1 Medians and mean inter-quartile
ranges of eye-blink rate and pulse rate dif-
ferences for the control group and the ex-
perimental groups (Sandalwood oil and san-
talol); H on the top of the bars indicates sig-
nificant differences (P
£
0.050) between the
control group and the experimental groups,
* on top of the bars indicates significant dif-
ferences (P
£
0.050) between the experi-
mental groups.
Heuberger E et al. East Indian Sandalwood ¼ Planta Med 2006; 72: 792 ± 800
Original Paper
796
Downloaded by: Saarländische Universitäts- u. Landesbibliothek. Copyrighted material.
water, did not significantly alter overall physiological or behav-
ioral arousal, although a decrease of skin temperature, higher at-
tentiveness and better mood were observed. These findings con-
trast results of previous investigations in which Sandalwood oil
showed deactivating effects when it was applied percutaneously
[11], [14]. The disagreement between these data possibly reflects
the impact of the route of administration of odorants. Although
in experimental animals Sandalwood oil showed sleep-inducing
and sedating effects also upon inhalation [12], [13], our results
are supported by a recent investigation in humans [20]. These
authors reported that a number of odors which were perceived
as pleasant and comfortable significantly decreased alpha
Fig. 3 Medians and mean inter-quartile
ranges of systolic and diastolic blood pres-
sure differences for the control group and
the experimental groups (Sandalwood and
santalol); difference 2 ±4: difference be-
tween measurements 2 and 4, difference
3 ± 4: difference between measurements 3
and 4; * on top of the bars indicates signifi-
cant differences (P
£
0.050) between the ex-
perimental groups.
Fig. 4 Medians and mean inter-quartile
ranges of subjective attentiveness and re-
laxation differences for the control group
and the experimental groups (Sandalwood
oil and santalol); difference 2 ± 4: difference
between ratings 2 and 4, difference 3 ±4:
difference between ratings 3 and 4; H on
the top of the bars indicates significant dif-
ferences (P
£
0.050) between the control
group and the experimental groups, * on
top of the bars indicates significant differen-
ces (P
£
0.050) between the experimental
groups.
Heuberger E et al. East Indian Sandalwood ¼ Planta Med 2006; 72: 792 ± 800
Original Paper
797
Downloaded by: Saarländische Universitäts- u. Landesbibliothek. Copyrighted material.
rhythm, but that Sandalwood odor which was experienced as
unpleasant, induced uncomfortable feelings and did not sup-
press alpha 1 activity. We found significant differences between
the intensity ratings of the control group and the experimental
groups, which demonstrate that the odor concentrations of both
Sandalwood oil and
a
-santalol were well above the detection
threshold, even after an inhalation period of 20 minutes. Many,
if not all odorants have the tendency to stimulate the trigeminal
nerve, and this propensity gets stronger with increasing concen-
tration [21]. Thus, one explanation for the results of the present
study could be that Sandalwood oil stimulated trigeminal nerve
endings located in the nasal mucosa. Activation of the trigeminal
system may have elevated physiological arousal levels, e. g., via
the ascending reticular activating system. Reports of pungent
and itchy nasal sensations by our subjects are in agreement
with this hypothesis. In a follow-up study using ten-fold dilu-
tions of Sandalwood oil and
a
-santalol, both odors induced tri-
geminal stimulation [22]. However, concentrations used in
Fig. 5 Medians and mean inter-quartile
ranges of subjective alertness and mood dif-
ferences for the control group and the ex-
perimental groups (Sandalwood oil and san-
talol); difference 2±4: difference between
ratings 2 and 4, difference 3 ± 4: difference
between ratings 3 and 4; H on the top of
the bars indicates significant differences (P
£
0.050) between the control group and
the experimental groups.
Fig. 6 Medians and mean inter-quartile
ranges of odor intensity and odor effect dif-
ferences for the control group and the ex-
perimental groups (Sandalwood oil and San-
talol); H on the top of the bars indicates sig-
nificant differences (P
£
0.050) between the
control group and the experimental groups,
* on top of the bars indicates significant dif-
ferences (P
£
0.050) between the experi-
mental groups.
Heuberger E et al. East Indian Sandalwood ¼ Planta Med 2006; 72: 792 ± 800
Original Paper
798
Downloaded by: Saarländische Universitäts- u. Landesbibliothek. Copyrighted material.
more natural settings, such as in aromatherapy practice, are
probably much lower than in our experiment, and it remains un-
clear whether arousing effects would also be observed under
these conditions.
Comparison of the experimental groups showed differences in
the stimulant properties of the fragrances. Subjects who had in-
haled essential Sandalwood oil showed higher overall physiol-
ogical and behavioral arousal levels than those who had inhaled
a
-santalol, although subjects in the
a
-santalol group felt more
attentive than those in the Sandalwood oil group. Differences be-
tween the fragrances were also obvious in terms of intensity rat-
ings, the odor of Sandalwood oil being experienced as more in-
tense than that of
a
-santalol. Sandalwood odor, but not
a
-santa-
lol odor, tended to be rated more stimulating than the odor of the
placebo substance. It may be speculated that differences in sti-
mulus characteristics between Sandalwood oil and
a
-santalol
are associated with differences in their arousing properties.
With respect to autonomic arousal, this relation has been discuss-
ed by other authors who found that unpleasant odor stimuli in-
duced different patterns of ANS activation and, in general, higher
autonomic arousal than pleasant smells [23], [24], [25], [26]. In a
recent investigation [27], intensity and arousal ratings of the sti-
muli were positively correlated with skin conductance varia-
tions. The latter relation was also obvious in the Sandalwood oil
group in the present investigation. In this group, subjective rat-
ings of the stimulating effect of the odor were also correlated
with subjective vigor, and vigor ratings covaried with skin con-
ductance and eye-blink rate. These findings suggest that psycho-
logical mechanisms triggered by a scent mediated the increase of
arousal. Regarding single physiological and behavioral measures,
inhalation of
a
-santalol produced some stimulating effect which
seems to have occurred mostly via psychological mechanisms.
Correlations between odor ratings and behavioral measures sug-
gest that odor pleasantness was the determining factor for these
effects. On the other hand, the mass of evaporated Sandalwood
oil was significantly greater than that of
a
-santalol. While this
difference is very likely due to dissimilar physico-chemical prop-
erties, e. g., vapor pressure, of the two fragrances, it may have
evoked different levels of activation of the trigeminal system
and could therefore alternatively explain the difference in stimu-
lant effect between Sandalwood oil and
a
-santalol.
Animal studies have shown that, after i.p. administration, seda-
tive effects of Sandalwood oil may be attributed to both
a
- and
b
-
santalol [13]. A pilot investigation by our group (unpublished
data) in which
b
-santalol was applied to the skin of 4 healthy hu-
man subjects also indicated that this component contributes to
the effects of Sandalwood oil on human arousal. Although to
our knowledge there are no reports on the inhalation of
b
-santa-
lol in either experimental animals or humans and we can there-
fore only speculate about its impact, it cannot be ruled out that
the effects of Sandalwood oil in the present investigation were
in part elicited by
b
-santalol. Future studies with an adequate
sample size will have to prove this assumption.
The results of the present study supplement previous research
performed by this group [14], [16], [17] and indicate (i) that, in
humans, the effects of fragrances on arousal may depend on ad-
ministration route, and (ii) that, when fragrances are adminis-
tered by means of inhalation and olfactory processing takes
place, several mechanisms may be involved which may be active
simultaneously. To thoroughly understand the mode of action of
volatile chemicals it is necessary to study the full range of their
effects ± those that can be observed after inhalation as well as
those that are unrelated to sensory processing.
Acknowledgements
The authors are grateful to Sirindhorn Scholarship, Srinakharin-
wirot University, Bangkok, Thailand (grant for T.H.) and to Drago-
co (now Symrise) GmbH, Vienna, for financial support of this
study.
References
1
Krotz A, Helmchen G. Total syntheses, optical rotations and fragrance
properties of sandalwood constituents: (±)-(Z)- and (±)-(E)-
b
-santalol
and their enantiomers, ent-
b
-santalene. Liebigs Ann Chem 1994; 6:
601±9
2
Banerjee S, Ecavade A, Rao AR. Modulatory influence of sandalwood
oil on mouse hepatic glutathione S-transferase activity and acid solu-
ble sulphydryl level. Cancer Lett 1993; 68: 105 ±9
3
Dwivedi C, Zhang Y. Sandalwood oil prevents skin tumour develop-
ment in CD1 mice. Eur J Cancer Prev 1999; 8: 449 ± 55
4
Dwivedi C, Guan X, Harmsen WL, Voss AL, Goetz-Parten DE, Koopman
EM et al. Chemopreventive effects of alpha-santalol on skin tumor de-
velopment in CD-1 and SENCAR mice. Cancer Epidemiol Biomarkers
Prev 2003; 12: 151 ±6
5
Benencia F, Courreges MC. Antiviral activity of sandalwood oil against
Herpes simplex viruses-1 and -2. Phytomedicine 1999; 6: 119 ± 23
6
Imai S, Oosato T, Sugiura A, Tsunakawa M, Kawasaki Y, Nagai K. Anti-
viral agents containing
a
-or
b
-pinene, d-limonene, or sandalwood oil.
Chem Abstracts 1996; 124: 250907n
7
Hammer KA, Carson CF, Riley TV. In-vitro activity of essential oils, in
particular Melaleuca alternifolia (tea tree) oil and tea tree oil products,
against Candida spp. J Antimicrob Chemother 1998; 42: 591 ±5
Fig. 7 Mean mass and SEM of inhaled fragrance; * on top of the bars
indicates significant differences (P
£
0.050) between the Sandalwood
oil group and
a
-santalol group.
Heuberger E et al. East Indian Sandalwood ¼ Planta Med 2006; 72: 792 ± 800
Original Paper
799
Downloaded by: Saarländische Universitäts- u. Landesbibliothek. Copyrighted material.
8
Tisserand R. The art of aromatherapy. Essex: CW Daniel, 1977
9
Jellinek JS. Psychodynamic odor effects and their mechanisms. Cosmet
Toiletries 1997; 112: 61± 71
10
Buchbauer G, Jirovetz L, Jager W, Plank C, Dietrich H. Fragrance com-
pounds and essential oils with sedative effects upon inhalation. J
Pharm Sci 1993; 82: 660 ± 4
11
Ide N, Hanata T. Cosmetics containing sleep-inducing fragrances.
Chem Abstracts 1997; 128: 53073u
12
Komori T, Tanida M, Nakamura S. Sleep-inducing perfume composi-
tions. Chem Abstracts 1996; 124: 155727v
13
Okugawa H, Ueda R, Matsumoto K, Kawanishi K, Kato A. Effect of
a
-
santalol and
b
-santalol from Sandalwood on the central nervous sys-
tem in mice. Phytomedicine 1995; 2: 119 ± 26
14
Hongratanaworakit T, Heuberger E, Buchbauer G. Evaluation of the ef-
fects of East Indian sandalwood oil and
a
-santalol on humans after
transdermal absorption. Planta Med 2004; 70: 3 ± 7
15
Braun NA, Meier M, Pickenhagen W. Isolation and chiral GC analysis of
b
-bisabolols-trace constituents from the essential oil of Santalum
album L. (Santalaceae). J Ess Oil Res 2003; 15: 63 ± 5
16
Heuberger E, Hongratanaworakit T, Bohm C, Weber R, Buchbauer G.
Effects of chiral fragrances on human autonomic nervous system
parameters and self-evaluation. Chem Senses 2001; 26: 281± 92
17
Heuberger E, Redhammer S, Buchbauer G. Transdermal absorption of
(±)-linalool induces autonomic deactivation but has no impact on rat-
ings of well-being in humans. Neuropsychopharmacology 2004; 29:
1925± 32
18
Oldfield RC. The assessment and analysis of handedness: the Edin-
burgh inventory. Neuropsychologia 1971; 9: 97 ± 113
19
Bortz J, Lienert GA, Boehnke K. Verteilungsfreie Methoden in der Bio-
statistik. Berlin: Springer, 1990
20
Masago R, Matsuda T, Kikuchi Y, Miyazaki Y, Iwanaga K, Harada H et al.
Effects of inhalation of essential oils on EEG activity and sensory eval-
uation. J Physiol Anthropol Appl Human Sci 2000; 19: 35 ± 42
21
Doty RL, Cometto-Muæiz JE. Trigeminal chemosensation. In: Hand-
book of Olfaction and Gustation Doty RL, editor. New York: Marcel
Dekker, 2003: p 981± 99
22
Heuberger E, Springsics C, Meddeb R, Buchbauer G. Trigeminal che-
mosensation and its relation to physiological odor effects. 35th ISEO,
Messina, Italy: 2004
23
Alaoui-Ismaili O, Vernet-Maury E, Dittmar A, Delhomme G, Chanel J.
Odor hedonics: connection with emotional response estimated by au-
tonomic parameters. Chem Senses 1997; 22: 237 ±48
24
Brauchli P, Ruegg PB, Etzweiler F, Zeier H. Electrocortical and auto-
nomic alteration by administration of a pleasant and an unpleasant
odor. Chem Senses 1995; 20: 505± 15
25
Robin O, Alaoui-Ismaili O, Dittmar A, Vernet-Maury E. Basic emotions
evoked by eugenol odor differ according to the dental experience. A
neurovegetative analysis. Chem Senses 1999; 24: 327± 35
26
Nagai M, Wada M, Usui N, Tanaka A, Hasebe Y. Pleasant odors attenu-
ate the blood pressure increase during rhythmic handgrip in humans.
Neurosci Lett 2000; 289: 227 ± 9
27
Bensafi M, Rouby C, Farget V, Bertrand B, Vigouroux M, Holley A. Influ-
ence of affective and cognitive judgments on autonomic parameters
during inhalation of pleasant and unpleasant odors in humans. Neuro-
sci Lett 2002; 319: 162 ± 6
Heuberger E et al. East Indian Sandalwood ¼ Planta Med 2006; 72: 792 ± 800
Original Paper
800
Downloaded by: Saarländische Universitäts- u. Landesbibliothek. Copyrighted material.
... , Heuberger et al. (2006) sandalwood seed oil and with other chemical substances. Antimicrobial plasticizer, lather promoter, and solidifying and moistening substance could be formed using the sandalwood-based oil. ...
Chapter
Sandalwood (Santalum album Linn.) is an important tree species that exhibits high medicinal, cosmetic, and commercial values. Indian sandalwood is available mostly from Karnataka and Tamilnadu states of India. Due to its wide uses in various industries, wood is high in demand in the international market. The commercial aspect of sandalwood is being regulated by the forest authorities. It also shows numerous uses in cosmetic industries including the manufacturing of beauty products, face packs, moisturizers, face wash, skin creams, etc. Sandalwood is an important requirement in various rituals in almost all religious ceremonies. Sandalwood oil is being traditionally used in curing various diseases and ailments. It shows antioxidant, antiviral, anticancer, antifungal, antipyretic, anti-inflammatory, and antipyretic activity. Aromatherapy is one of the important medicinal uses of sandalwood. This chapter discusses the commercial, cosmetic, and medicinal importance of sandalwood.
... Research has identified a range of properties of sandalwood oil and its constituents behind these uses, including anti-fungal (Warnke et al., 2009), antiviral against drug-resistant herpes simplex virus (Schnitzler et al., 2007), anti-carcinogenic (Burdock and Carabin, 2008), and anti-influenza HK (H3N2) anti-viral capacities (Paulpandi et al., 2012). S. album oil was also recorded as helping to address pulse rate issues, skin conductance, and cytosolic blood pressure (Heubeger et al., 2006). S. album exploitation and use is part of a long and rich cultural heritage that dates back some 5,000 years and is even mentioned in the ancient Sanskrit manuscripts (Flansda, 2009). ...
Article
Full-text available
Parasitic plants are mostly viewed as pests. This is caused by several species causing serious damage to agriculture and forestry. There is however much more to parasitic plants than presumed weeds. Many parasitic plans exert even positive effects on natural ecosystems and human society, which we review in this paper. Plant parasitism generally reduces the growth and fitness of the hosts. The network created by a parasitic plant attached to multiple host plant individuals may however trigger transferring systemic signals among these. Parasitic plants have repeatedly been documented to play the role of keystone species in the ecosystems. Harmful effects on community dominants, including invasive species, may facilitate species coexistence and thus increase biodiversity. Many parasitic plants enhance nutrient cycling and provide resources to other organisms like herbivores or pollinators, which contributes to facilitation cascades in the ecosystems. There is also a long tradition of human use of parasitic plants for medicinal and cultural purposes worldwide. Few species provide edible fruits. Several parasitic plants are even cultivated by agriculture/forestry for efficient harvesting of their products. Horticultural use of some parasitic plant species has also been considered. While providing multiple benefits, parasitic plants should always be used with care. In particular, parasitic plant species should not be cultivated outside their native geographical range to avoid the risk of their uncontrolled spread and the resulting damage to ecosystems.
... Furthermore, it additionally diminishes the probability of dermal malignancy (Dickinson et al. 2014). A past study has documented that the utilization of sandalwood oil (predominantly consisting of α-santalols) from east India, via aromatherapy, resulted in an augmented rate of heart beating, systolic hypertension, and dermal conductance (Buchbauer 2006). Even though photosynthesis is an integral feature of the Santalum trees, they act as hemi-parasitic, including possessing roots, which in order to receive nutrients and water, first observe and then knock on to the adjacent tree root machinery. ...
Chapter
Essential oils, secreted by plants, are primarily meant for various physiological, ecological, and defense activities. These oils belong to various classes, i.e., isolates of fatty acids, isoprenoids, and phenolic complexes, and can be secreted by various organs of plants. The essential oil market globally has been predicted to grow at a compound annual growth rate (CAGR) of ~8–10%, and reach a staggering figure in excess of USD ten billion in the next 5 years or so. However, the challenge lies in commercial production, keeping pace with the demand, since their natural production in plants is in considerably low quantities, which depends on ecological conditions and growth stages of the plant. Although several investigations exist in the literature, there is a pressing need for a systematic review of the recent updates, particularly concerning the strategies that facilitate the manufacturing of such indispensable oils. The current chapter focuses on various facets of essential oil production, the associated challenges, and the promise of genetic alteration techniques for enhanced essential oil production. Several distinct perspectives have been considered, such as different sources and mechanisms of essential oil biomanufacturing, including their role in plant defense, the array of isolation procedures, and their wide ranges of beneficial attributes, particularly catering to the therapeutic potential, and challenges and metabolic engineering characteristics. A crucial feature of the current chapter is a critical review, underlining these aspects with a case study, using the commercially valuable sandalwood oil as an example, to emphasize the genetic modification strategies for enhancing sandalwood oil.
Book
This book provides a global perspective of Indian Sandalwood categorized as ‘Vulnerable’ by the International Union for Conservation of Nature. It deals with history, distribution, propagation, chemistry, utilization, improvement, trade, and conservation in the present context. This book explores ways and means for restoring its past glory by creating awareness for its conservation and sustainable utilization. The content encompasses informative tables, appropriate graphs and figures, and illustrations with photographs and line drawings. This compendium would be useful for foresters, forestry professionals, botanists, policymakers, conservationists, NGOs, and researchers in the academia and the industry sectors.
Chapter
Sandalwood is a valued and widely used ingredient in perfumery. It has a history of use in India that documents back to the seventh century BCE. Its use in Western perfumery is not as long, but the unique qualities of this ingredient have seen it become a key ingredient in these products. By undertaking a review of the history of perfume development, exploring how Indian sandalwood works in these compositions, the benefit that this ingredient can bring to the final product and then looking at the chemistry of the constituents of sandalwood oil will allow a better understanding on why Indian sandalwood is so valued in this purpose. A comment on the future of Indian sandalwood is offered, and while some new opportunities exist such as sustainability, origin and traceability, there are also opportunities with developing some of the well-being benefits, associated with Indian sandalwood in the East for many years, into Western perfume compositions.
Chapter
In this chapter, we focus on the current status of knowledge on the floral biology of Santalum album and the role of flower visitors in its pollination and fruit set. Flowers are bisexual, actinomorphic and epigynous, borne on axillary or terminal panicles. Based on the position of stigma, three types of flowers are observed: pin (stigma above the level of anther), thrum (stigma at a lower level) and homostylous (stigma and anther at the same level). A flower lasts for about three days, and its colour gradually changes from pale green or white to dark red with age. Though the ovary has 2‒4 embryo sacs, only one matures. From flowering to fruit maturation, it takes 80‒85 days, and the berries are eaten by birds, especially the Asian Koel, which may also be involved in the dispersion of seeds. There appear to be some contradictions concerning pollination, though many workers suggest that S. album is an obligate outcrossing species. However, the per cent fruit set under open pollination conditions appears to be very low, indicating a deficit in pollinators. Of the 46 species of flower visitors recorded, syrphids, calliphorids and honey bees have been reported as the most frequent visitors. However, there have been no studies to identify efficient pollinators, as most of the reports are subjective and are not supported by hard data. We also discuss the methods to be followed in sandalwood pollination studies.
Chapter
The use of essential oils to control arousal and cognitive performance has a long tradition in mankind. In our time, the demand for remedies promising fast but safe recovery from mental stress is ever-growing. Thus, today a plethora of popular aromatherapy guidebooks exists, offering advice on the use of essential oils for a multitude of health complaints. With some delay, scientists have started to substantiate the claims raised in the popular literature and verify the effects of essential oils on cognitive functioning and performance. This chapter aims to give an overview about the available scientific literature dealing with the influence of essential oils and fragrances on arousal and cognitive performance. The topics covered in this chapter will range from brain potentials related to arousal over alertness and attention to learning and memory. In addition, it will be discussed whether olfactory versus non-olfactory administration influences the effects of essential oils on cognitive functions and how psychological phenomena, such as hedonic preferences, semantic associations, and individual expectations may shape these effects.
Article
Full-text available
Research suggests that transient emotional episodes produces sustained effects on psychological functions and brain activity during subsequent resting state. In this fMRI study we investigated whether transient emotions induced by smells could impact brain connectivity at rest in a valence-specific manner. The results suggest a sustained reconfiguration of parts of the default mode network which become more connected with areas implicated in olfactory processing, emotional learning, and action control. We found lingering effects of odorants on subsequent resting state that predominantly involved connections of the precuneus with a network comprising the insula, amygdala, medial orbital gyrus. Unpleasant smells in particular predicted greater coupling between insula, hippocampal structures, and prefrontal cortex, possible reflecting enhanced aversive learning and avoidance motivation. More broadly, our study illustrates a novel approach to characterize the impact of smells on brain function and differentiate the neural signatures of their valence, during task-free rest conditions.
Article
Full-text available
East Indian Sandalwood Oil (EISO) has diverse beneficial effects and has been used for thousands of years in traditional folk-medicine for treatment of different human ailments. However, there has been no in-depth scientific investigation to decipher the neuroprotective and geroprotective mechanism of EISO and its principle components, α- and β-santalol. Hence the current study was undertaken to assess the protective effects of EISO, and α- and β-santalol against neurotoxic (6-OHDA/6-hydroxydopamine) and proteotoxic (α-synuclein) stresses in a Caenorhabditis elegans model. Initially, we found that EISO and its principle components exerted an excellent antioxidant and antiapoptotic activity as it was able to extend the lifespan, and inhibit the ROS generation, and germline cell apoptosis in 6-OHDA-intoxicated C. elegans. Further, we showed that supplementation of EISO, and α- and β-santalol reduced the 6-OHDA and α-synuclein-induced Parkinson's disease associated pathologies and improved the physiological functions. The genetic and reporter gene expression analysis revealed that an EISO, or α- and β-santalol-mediated protective effect does not appear to rely on DAF-2/DAF-16, but selectively regulates SKN-1 and its downstream targets involved in antioxidant defense and geroprotective processes. Together, our findings indicated that EISO and its principle components are worth exploring further as a candidate redox-based neuroprotectant for the prevention and management of age-related neurological disorders.
Chapter
Full-text available
In this chapter, basic aspects of the anatomy, physiology, and chemical responsiveness of the human trigeminal system were reviewed. Additionally, studies demonstrating that ocular trigeminal sensitivity may be similar to intranasal trigeminal sensitivity were reviewed. Among other topics addressed were the functional dissociation of CN I and CN V responses, the application of modern structure-activity studies in predicting irritative responses of volatiles, and an assessment of potential functional interactions between CN I and CN V. It is apparent from the material reviewed in this chapter that the trigeminal system is generally less sensitive to volatile agents than the olfactory system, and very few, if any, odorants fail to stimulate CN V at high enough concentrations. It is pointed out that knowledge of the factors responsible for nasal and ocular irritation is not only of theoretical interest, but of practical interest as well, particularly in relation to environmental concerns. See full chapter at: http://escholarship.org/uc/item/5wm4g2gq
Article
Full-text available
The aim of this paper is to analyse the relationship between self-report hedonic evaluations and the physiological expression of emotion in response to odorants. We try to solve the following questions: (1) Is it possible to find any experimental evidence that the sense of smell is linked with emotion? (2) What kind of odorants can be distinguished by autonomic analysis? (3) Is there a link between hedonics and autonomic information? The effects of odorants on the emotional process were estimated, in terms of autonomic nervous system (ANS) activity. Fifteen subjects inhaled five odorants as olfactory stimuli: lavender (LAV), ethyl acetoacetate (EAA), camphor (CAM), acetic acid (AA) and butyric acid (BA). After inhaling the odorant, subjects were requested to fill out an 11-point hedonic scale to rate its pleasantness versus unpleasantness. ANS parameters were as follows: two electrodermal responses, skin potential (SP) and resistance (SR); two thermovascular parameters, skin blood flow (SBF) and skin temperature (ST); and two cardiorespiratory parameters; instantaneous respiratory frequency (IRF) and instantaneous heart rate (IHR). Simultaneous recording of six parameters showed that specific autonomic patterns were associated with each odorant. An analysis of variance made it possible to differentiate among the five odorants. Two-by-two odorant comparisons for autonomic responses using Tukey's HSD multiple comparison test only permitted differentiation between pleasant odorants (LAV and EAA) and unpleasant (AA and BA) ones, but camphor was differentiated from both pleasant and unpleasant odorants. Each odorant elicited responses in the different parameters, yet subjects responded through their preferential channels; an average of two channels was used by each subject. These results when compared with those obtained with other senses (visual and auditory), did not evidence the postulated preferential link between olfaction and emotion. A strong link between hedonics and ANS response could be demonstrated when considering each subject and mainly through his/her preferential channel(s); conversely a weak correlation (SR duration excepted) was obtained between inter-subjects' hedonic evaluation. It seems that for a given population the autonomic response reflect the odor valence only through some parameters related to the main preferential channel(s) and thus the global autonomic pattern has to be considered.
Article
The essential oil produced from the heartwood of Santalum album L. was analyzed using GC/MS. Forty-four constituents were identified: one monoterpene and 43 sesquiterpenes. 2,10-Bisaboladien-6-ol (= β-bisabolol/epi-β-bisabolol) was one of the trace compounds found in east Indian sandalwood oil. Chiral GC analysis showed that besides the main stereoisomer, which possessed an (R,R)-configuration, all three other isomers were also present.
Article
Enantiomerically pure 5-norbornene-2-carboxylic acids 4, obtained by asymmetric Diels-Alder additions, were oxidatively degraded to (+)- and (−)-2-norbornanone [(+)-, (−)-21] and (+)- and (−)-3-methyl-2-norbornanone [(+)-, (-)-11] which were converted into the title compounds by stereoselective alkylations, subsequent cis- and trans-selective Wittig reactions and reductions. Precise optical rotations were determined for (Z)- and (E)-β-santalol (1 and 2) and β-santalene (3a) which were obtained by total synthesis and, in addition, by isolation from East Indian sandalwood oil.
Article
Sandalwood (Byakudan in Japanese; Santalum album L.) is used as a popular sedative in Oriental medicine. Extracts of the wood of Santalum album were obtained by successively extracting with benzene, chloroform, methanol and water. Each of these fractions was tested for activity on the central nervous system of mice following intraperitoneal administration, i.e. potentiation of hexobarbital sleeping time, body temperature alterations, antinociceptive and spontaneous motor activity changes. The benzene extract was active in these assays and was then separated further into fractions 1, 2 and 3. Fraction 2 was shown to be the most active in the aforementioned assays, α- and β-Santalols were isolated from this active fraction as the major CNS active constituents. They were both active by the intragastric and intracerebroventricular routes of administration. Thus, it can be considered that α- and β-santalols contribute to the reputed sedative effect of sandalwood preparations in Oriental medicine. Additionally, α- and β-santalols significantly increased the levels of homovanillic acid, 3,4-dihydroxyphenylacetic acid and/or 5-hydroxyindoleacetic acid in the brain of mice, and chlorpromazine did the ones of homovanillic acid and 3,4-dihydroxyphenylacetic acid. These results showed that α- and β-santalols could be considered as neuroleptic by resemblance to the pharmacological activities of chlorpromazine.
Article
Fragrance compounds and essential oils with sedative effects influence the motility of mice in inhalation studies under standardized conditions. A significant drop in the motility of mice was registered following exposure to these fragrances. The same results were achieved when the mice were artificially induced into overagitation by intraperitoneal application of caffeine and subsequently subjected to inhalation of fragrance compounds and essential oils. These results proved the sedative effects of these fragrants via inhalative exposure in low concentrations. Blood samples were taken from the mice after a 1-h inhalation period. Chromatographic and spectroscopic methods were used to detect and characterize the actual effective compounds after solid-phase extraction. Serum concentrations of 42 different substances, including fragrance compounds, were found in low ranges (ng/mL serum). The results contribute to the correct interpretation of the term aromatherapy (i.e., a stimulating or sedative effect on the behaviour of individuals only upon inhalation of fragrance compounds).
Article
The need for a simply applied quantitative assessment of handedness is discussed and some previous forms reviewed. An inventory of 20 items with a set of instructions and response- and computational-conventions is proposed and the results obtained from a young adult population numbering some 1100 individuals are reported. The separate items are examined from the point of view of sex, cultural and socio-economic factors which might appertain to them and also of their inter-relationship to each other and to the measure computed from them all. Criteria derived from these considerations are then applied to eliminate 10 of the original 20 items and the results recomputed to provide frequency-distribution and cumulative frequency functions and a revised item-analysis. The difference of incidence of handedness between the sexes is discussed.
Article
The effect of the oil from the wood of Santalum album on glutathione S-transferase (GST) activity and acid soluble sulphydryl (SH) levels in the liver of adult male Swiss albino mice was investigated. Oral feeding by gavage to mice each day with 5 and 15 microliters sandalwood oil for 10 and 20 days exhibited an increase in GST activity in time- and dose-responsive manners. Feeding a dose of 5 microliters sandalwood oil for 10 and 20 days caused, respectively, a 1.80-fold (P < 0.001) and 1.93-fold (P < 0.001) increase in GST enzyme activity, while feeding a dose of 15 microliters of the oil per day for 10 and 20 days induced, respectively, 4.73-fold (P < 0.001) and 6.10-fold (P < 0.001) increases in the enzyme's activity. In addition, there were 1.59-fold (P < 0.001) and 1.57 (P < 0.001) increases in acid-soluble SH levels in the hepatic tissue of the mice following feeding of the oil at the dose levels of 5 and 15 microliters for 10 days. Furthermore, mice fed on a diet containing 1% 2(3)-butyl-4-hydroxyanisole (positive control) also showed an increase in hepatic GST activity and SH levels. Enhancement of GST activity and acid-soluble SH levels are suggestive of a possible chemopreventive action of sandalwood oil on carcinogenesis through a blocking mechanism.
Article
The present study was designed to investigate whether there is a consistent response in ongoing EEG due to repetitive olfactory stimulation. Two odors of different hedonic quality were presented bilaterally to five male subjects at suprathreshold levels. A room-air blank served as the control stimulus. Each odor was presented six times to each subject in each of three sessions. Electrocortical activity, heart rate, skin conductance and breathing cycle were recorded continuously. EEG variables assessed were difference scores of absolute power in the frequency bands theta, alpha1, alpha2 and beta1 at eight locations. Phenylethyl alcohol was rated pleasant, while valeric acid was judged unpleasant. Within 8 s after stimulus release, valeric acid increased alpha2 power, whereas phenylethyl alcohol did not. No further frequency bands were affected by olfactory stimulation. These findings suggest that smelling an unpleasant odor leads to a cortical deactivation. Chem. Senses 20: 505–515, 1995.