ArticlePDF Available

Volatile Organic Compounds Emissions from Luculia pinceana Flower and Its Changes at Different Stages of Flower Development

MDPI
Molecules
Authors:
Yuying Li
Yuying Li
Hong Ma
Hong Ma
Hong Ma
  • This person is not on ResearchGate, or hasn't claimed this research yet.
Youming Wan
Youming Wan
Youming Wan
  • This person is not on ResearchGate, or hasn't claimed this research yet.
Taiqiang Li
Taiqiang Li
Taiqiang Li
  • This person is not on ResearchGate, or hasn't claimed this research yet.
Show all 7 authorsHide
Download full-text PDF
Read full-text
Download citation

Abstract and Figures

Luculia plants are famed ornamental plants with sweetly fragrant flowers, of which L. pinceana Hooker, found primarily in Yunnan Province, China, has the widest distribution. Solid phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS) was employed to identify the volatile organic compounds (VOCs) emitted from different flower development stages of L. pinceana for the evaluation of floral volatile polymorphism. Peak areas were normalized as percentages and used to determine the relative amounts of the volatiles. The results showed that a total of 39 compounds were identified at four different stages of L. pinceana flower development, including 26 at the bud stage, 26 at the initial-flowering stage, 32 at the full-flowering stage, and 32 at the end-flowering stage. The most abundant compound was paeonol (51%–83%) followed by (E,E)-α-farnesene, cyclosativene, and δ-cadinene. All these volatile compounds create the unique fragrance of L. pinceana flower. Floral scent emission offered tendency of ascending first and descending in succession, meeting its peak level at the initial-flowering stage. The richest diversity of floral volatile was detected at the third and later periods of flower development. Principal component analysis (PCA) indicated that the composition and its relative content of floral scent differed throughout the whole flower development. The result has important implications for future floral fragrance breeding of Luculia. L. pinceana would be adequate for a beneficial houseplant and has a promising prospect for development as essential oil besides for a fragrant ornamental owing to the main compounds of floral scent with many medicinal properties.
Figures - available from: Molecules
This content is subject to copyright.
Access to this full-text is provided by MDPI.
Content available from Molecules 
This content is subject to copyright.
molecules
Article
Volatile Organic Compounds Emissions from
Luculia pinceana Flower and Its Changes at Different
Stages of Flower Development
Yuying Li 1,† , Hong Ma 1, †, Youming Wan 1, Taiqiang Li 1, Xiuxian Liu 1, Zhenghai Sun 2and
Zhenghong Li 1, *
1Research Institute of Resource Insects, Chinese Academy of Forestry, Kunming 650224, China;
liyuy_ing@163.com (Y.L.); hortscience@163.com (H.M.); wanyouming@126.com (Y.W.);
li_taiqiang@163.com (T.L.); lxx205@126.com (X.L.)
2School of Gardening, Southwest Forestry University, Kunming 650224, China; sunzhenghai1978@163.com
*Correspondence: lzh4949@163.com; Tel.: +86-871-386-0032; Fax: +86-871-386-0027
† These authors contributed equally to this work.
Academic Editor: Derek J. McPhee
Received: 22 February 2016; Accepted: 18 April 2016; Published: 22 April 2016
Abstract:
Luculia plants are famed ornamental plants with sweetly fragrant flowers, of which
L. pinceana Hooker, found primarily in Yunnan Province, China, has the widest distribution. Solid
phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS) was employed to
identify the volatile organic compounds (VOCs) emitted from different flower development stages
of L. pinceana for the evaluation of floral volatile polymorphism. Peak areas were normalized as
percentages and used to determine the relative amounts of the volatiles. The results showed that
a total of 39 compounds were identified at four different stages of L. pinceana flower development,
including 26 at the bud stage, 26 at the initial-flowering stage, 32 at the full-flowering stage, and
32 at the end-flowering stage. The most abundant compound was paeonol (51%–83%) followed by
(E,E)-
α
-farnesene, cyclosativene, and
δ
-cadinene. All these volatile compounds create the unique
fragrance of L. pinceana flower. Floral scent emission offered tendency of ascending first and
descending in succession, meeting its peak level at the initial-flowering stage. The richest diversity
of floral volatile was detected at the third and later periods of flower development. Principal
component analysis (PCA) indicated that the composition and its relative content of floral scent
differed throughout the whole flower development. The result has important implications for future
floral fragrance breeding of Luculia.L. pinceana would be adequate for a beneficial houseplant and
has a promising prospect for development as essential oil besides for a fragrant ornamental owing to
the main compounds of floral scent with many medicinal properties.
Keywords:
Luculia; volatile organic compound; flower development; SPME-GC-MS; houseplant;
floral scent
1. Introduction
Luculia Sweet is a small genus of the family Rubiaceae, consisting of about five types of
small trees or shrubs. Three species occur in China, amongst which
Luculia pinceana Hooker,
found
primarily in Yunnan Province at altitudes between 600 and 3000 m has the widest distribution in
Nature [
1
–
3
]. Luculia can be easily recognized by its compact and long-term blooming (usually April
to November) inflorescences with white to pink, sweetly fragrant flowers with extremely long corolla
tubes.
On account
of the above-mentioned advantages, Luculia plants have been widely introduced
around the world. Studies in the past are often concentrated on its reproductive system, distyly,
Molecules 2016,21, 531; doi:10.3390/molecules21040531 www.mdpi.com/journal/molecules
Molecules 2016,21, 531 2 of 10
molecular biology and gametophyte development [
1
–
7
]. In addition, as a traditional medicinal and
ornamental plant, research work is underway concerning its cultivation and breeding.
Floral fragrance is one of the most important characteristics of ornamental plants or cut flowers,
because it may affect people’s health and mood [
8
]. Thus, the study of the composition of floral
scent and the breeding of new ornamental plant cultivars with sweet-smelling or pleasant fragrance
have become new trends of the development of plant breeding nowadays [
9
]. Although L. pinceana
possess the features of long-term blooming, sweet fragrance and has great potential in serving as an
indoor plant, research on its floral scent has not been carried out. In this work, the volatile component
emissions from different flower development stages of L. pinceana were analyzed by solid phase
microextraction coupled with gas chromatography-mass spectrometry in order to build a foundation
for future work on Luculia floral fragrance breeding programs. Furthermore, the results could provide
a reference for determining whether Luculia species are suitable for indoor cultivation and extraction
of essential oil.
2. Results and Discussion
2.1. Identification of Scent Components
Thirty-nine VOCs were identified, representing more than 99% of the total emission of the
flowers. These volatiles grouped by their biochemical synthesis pathways [
10
] were described in
Table 1. A total of 18 same volatile compounds were shared at four different stages of flower
development of L. pinceana. Within these compounds, the main aroma-active one was paeonol
followed by (E,E)-
α
-farnesene, cyclosativene, and
δ
-cadinene. These compounds might dominate the
flavor for L. pinceana.
For instance,
paeonol has a specific odour; (E,E)-
α
-farnesene has a woody and
sweet odour;
δ
-Cadinene gives thyme, medicine and wood odour [
11
]. As one of these components,
γ
-muurolene has a smell of herb, wood and spice; methyl salicylate has a flavor with peppermint
aroma. The two compounds ranked second in relative content of VOCs at the full-flowering stage and
the end-flowering stage separately, so they could also influence the floral aroma.
The idea that L. pinceana has medicinal properties goes back hundreds of years in China [
12
].
Some of volatile compounds from flowers are pharmacologically active compounds. For example,
paeonol has several interesting biological activities, and it has been used as an anti-inflammatory,
analgesic, antioxidant, antidiabetic, and acaricidal agent [
13
,
14
]; cyclosativene demonstrates strong
anti-inflammatory, expectorant, antifungal effect [
15
];
γ
-muurolene and
δ
-cadinene have antifungal
properties. Despite the fact that essential oils are seldom encountered in the Rubiaceae [
16
], L. pinceana
would have a lot of potential for essential oil extraction according to the L. pinceana solid phase
microextraction results. Not only that, the essential oil of L. pinceana flowers might have special
therapeutic qualities in view of the above active ingredients among the volatile compounds.
Benzenoids were the most abundant amongst floral scent compounds, which content reached
at least 51%. The same scenario was noted in the floral essential oil of Randia matudae [
17
] compared
to other species of different genera in the family Rubiaceae. In contrast, the quantity and amount
of predominant compounds in the floral scent of Posoqueria latifolia [
18
], the leaf essential oil of
Rustia formosa and the essential oil from aerial parts of Anthospermum emirnense and A. perrieri were
sesquiterpenes [
16
,
19
]; the floral scent of Cephalanthus occidentalis,Warszewiczia coccinea and Gardenia
jasminoides were monoterpenes [
20
,
21
]; the floral scent of Coffea Arabica were aliphatics [
22
]. It has
been reported that the floral scent composition probably significantly varied amongst closely related
species, and our results partly support this view [10].
Molecules 2016,21, 531 3 of 10
Table 1. Volatile compounds identified in four different stages of L. pinceana flower development using SPME-GC-MS. (I) bud stage; (II) initial-flowering stage; (III)
full-flowering stage; and (IV) end-flowering stage.
Peak RT LRI Compounds CAS # Relative Content(%) ˘SD
I II III IV
Monoterpenes 1.48 ˘0.69b 0.15 ˘0.02b 1.63 ˘0.83b 7.91 ˘1.15a
1 8.37 904 (1S)-2,6,6-Trimethylbicyclo[3.1.1]hept-2-ene 7785-26-4 0b 0b 0b 0.45 ˘0.08a
2 8.75 918 Santolina triene 2153-66-4 0a 0a 0.32 ˘0.24a 0.34 ˘0.04a
3 9.46 943 α-Pinene 80-56-8 0b 0.05 ˘0.01b 0.26 ˘0.15b 2.11 ˘0.24a
4 10.84 994 Limonene 138-86-3 0a 0a 0.60 ˘0.43a 0.22 ˘0.03a
5 11.33 1012 3-Carene 13466-78-9 0.47 ˘0.48b 0.02 ˘0.00b 0.18 ˘0.12b 3.73 ˘0.61a
6 11.94 1034 (Z)-Verbenol 1845-30-3 0.05 ˘0.03a 0a 0.04 ˘0.02a 0a
7 12.37 1049 γ-Terpiene 99-85-4 0.03 ˘0.02a 0b 0b 0.03 ˘0.00a
8 12.64 1059 (E)-β-Ocimene 3779-61-1 0.87 ˘0.43a 0.02 ˘0.00b 0.09 ˘0.07b 0.61 ˘0.07ab
10 13.83 1102 α-Campholenal 91819-58-8 0b 0.02 ˘0.00b 0.07 ˘0.03a 0.08 ˘0.01a
11 14.36 1123 α-Santoline alcohol 90823-36-2 0.02 ˘0.01b 0.02 ˘0.00b 0.04 ˘0.03b 0.32 ˘0.06a
15 18.31 1295 Perilla alcohol 536-59-4 0.04 ˘0.02a 0.03 ˘0.00a 0.05 ˘0.02a 0.02 ˘0.00a
Aliphatics 2.46 ˘1.31a 0.53 ˘0.08a 1.46 ˘0.48a 2.81 ˘0.33a
12 14.84 1142 (3 E,5Z)-1,3,5-Undecatriene 51447-08-6 0.04 ˘0.02a 0a 0.06 ˘0.04a 0.03 ˘0.00a
14 17.39 1251 Nonanoic acid,ethyl ester 123-29-5 0c 0.01 ˘0.00b 0c 0.02 ˘0.00a
17 18.98 1318 Megastigma-4,6(E),8(E)-triene 51468-86-1 2.13 ˘1.28a 0.48 ˘0.07a 1.18 ˘0.53a 2.49 ˘0.31a
33 25.40 1577 Hexyl caprylate 1117-55-1 0.08 ˘0.05ab 0b 0.08 ˘0.02ab 0.10 ˘0.01a
34 25.62 1592 Pentanoic acid, 2,2,4-trimethyl-
3-carboxyisopropyl, isobutyl ester 959016-51-4 0.22 ˘0.13a 0.04 ˘0.00a 0.14 ˘0.02a 0.17 ˘0.02a
Benzenoids 51.61 ˘22.32a 85.88 ˘2.45a 80.05 ˘6.24a 75.38 ˘3.47a
13 15.08 1151 Methyl salicylate 119-36-8 0c 2.85 ˘0.45b 0c 4.81 ˘0.46a
23 22.43 1433 Paeonol 552-41-0 51.58 ˘22.36a 83.03 ˘2.91a 79.72 ˘6.14a 69.75 ˘4.00a
37 26.18 1639 Phenol,
2,6-bis(1,1-dimethylethyl)-4-(1-methylpropyl)
14035-34-8 0a 0a 0.30 ˘0.36a 0.04 ˘0.00a
39 27.75 1791 Benzyl benzoate 120-51-4 0.03 ˘0.04b 0b 0.03 ˘0.01b 0.78 ˘0.07a
Sesquiterpenes 44.41 ˘21.11a 13.37 ˘2.34a 16.79 ˘5.16a 13.91 ˘1.99a
18 19.87 1346 α-Cubebene 17699-14-8 2.21 ˘1.42a 0.32 ˘0.06a 0.28 ˘0.26a 0.52 ˘0.07a
19 20.35 1362 Cyclosativene 22469-52-9 4.96 ˘2.66a 1.04 ˘0.15a 2.07 ˘1.17a 1.87 ˘0.16a
20 21.12 1386 Isoledene 95910-36-4 5.45 ˘3.16a 0.96 ˘0.20a 0.57 ˘0.73a 1.06 ˘0.12a
21 21.53 1399 Caryophyllene 87-44-5 1.34 ˘0.76a 0.17 ˘0.03a 0.15 ˘0.08a 0.23 ˘0.01a
22 21.89 1413 β-Ylangene 20479-06-5 0b 0.02 ˘0.00b 0.09 ˘0.03a 0b
Molecules 2016,21, 531 4 of 10
Table 1. Cont.
Peak RT LRI Compounds CAS # Relative Content(%) ˘SD
I II III IV
24 23.37 1467 (-)-β-Cadinene 523-47-7 2.34 ˘1.35a 0.38 ˘0.06ab 0.58 ˘0.20ab 0.12 ˘0.01b
26 23.59 1476 γ-Muurolene 30021-74-0 0b 1.35 ˘0.22b 5.86 ˘1.95a 1.46 ˘0.14b
27 23.85 1485 Cubebol 23445-02-5 5.48 ˘3.14a 0.77 ˘0.11a 0.56 ˘0.63a 0.46 ˘0.08a
28 24.06 1493 (E,E)-α-Farnesene 502-61-4 2.46 ˘1.47a 3.89 ˘1.10a 4.90 ˘4.38a 4.75 ˘0.98a
29 24.30 1503 4- epi-Cubebol 23445-02-5 4.76 ˘2.65a 0.91 ˘0.15a 0.73 ˘0.82a 2.29 ˘0.30a
30 24.45 1513 δ-Cadinene 483-76-1 10.98 ˘6.25a 2.61 ˘0.10ab 0.64 ˘0.75b 0.60 ˘0.08b
31 24.62 1525 Cadine-1,4-diene 16728-99-7 3.19 ˘1.84a 0.77 ˘0.11a 0.25 ˘0.31a 0.42 ˘0.03a
35 25.69 1597 Cedrol 77-53-2 0.11 ˘0.06a 0a 0.05 ˘0.03a 0a
36 25.81 1606 α-Acorenol 28296-85-7 0.12 ˘0.07a 0a 0.07 ˘0.03a 0.05 ˘0.01a
38 26.33 1652 Cubenol 21284-22-0 1.02 ˘0.58a 0.18 ˘0.04ab 0b 0.07 ˘0.01b
Unknowns 0.03 ˘0.02ab 0.07 ˘0.01a 0.08 ˘0.03a 0b
9 12.95 1070 Unknown-1 - 0b 0b 0.02 ˘0.01a 0b
16 18.60 1306 Unknown-2 - 0b 0b 0.05 ˘0.02a 0b
25 23.44 1470 Unknown-3 - 0b 0.07 ˘0.01a 0b 0b
32 25.27 1568 Unknown-4 - 0.03 ˘0.02a 0b 0b 0b
Values, expressed as mean
˘
SD of triplicate measurements, with different letters (a–c) in the same raw were significantly different according to Tukey’s test (p< 0.05). RT: retention
time; LRI: linear retention index; CAS #: Chemical Abstracts Service Registry Number.
Molecules 2016,21, 531 5 of 10
2.2. Dynamic Changes of Scent Emission in Different Development Floral Stages
L. pinceana flowers were selected on the basis of their botanical characteristics to evaluate the
dynamic changes and diversity of floral volatiles according to different development stages: bud
stage, initial-flowering stage, full-flowering stage, and end-flowering stage (Figure 1). Table 1and
Figure 2show the distinct changes in scent composition and concentration across flowering stages.
Scent components were drastically emitted at the initial-flowering stage, and then declined gradually
at the full-flowering stage. The amount of VOCs at the bud stage and the end-flowering stage was
obviously lower than that at the initial-flowering stage. The emission pattern of L. pinceana flowering
stages was different from Cananga odorata [
23
], Vanda Mimi Palmer [
24
], and Hosta flowers [
25
] of which
the fragrance ingredients were drastically emitted at the full-flowering stage and decreased greatly
afterwards. These results showed that the emissions at different flower stages evidently differed.
Investigation of the spatial and temporal patterns of gene expression has provided new information
on the factors regulating the emission of plant volatile compounds [26].
Molecules 2016, 21, 531 5 of 10
2.2. Dynamic Changes of Scent Emission in Different Development Floral Stages
L. pinceana flowers were selected on the basis of their botanical characteristics to evaluate the
dynamic changes and diversity of floral volatiles according to different development stages: bud
stage, initial-flowering stage, full-flowering stage, and end-flowering stage (Figure 1). Table 1 and
Figure 2 show the distinct changes in scent composition and concentration across flowering stages.
Scent components were drastically emitted at the initial-flowering stage, and then declined gradually
at the full-flowering stage. The amount of VOCs at the bud stage and the end-flowering stage was
obviously lower than that at the initial-flowering stage. The emission pattern of L. pinceana flowering
stages was different from Cananga odorata [23], Vanda Mimi Palmer [24], and Hosta flowers [25] of
which the fragrance ingredients were drastically emitted at the full-flowering stage and decreased
greatly afterwards. These results showed that the emissions at different flower stages evidently
differed. Investigation of the spatial and temporal patterns of gene expression has provided new
information on the factors regulating the emission of plant volatile compounds [26].
Figure 1. The morphological characteristics of L. pinceana flower in four different stages. (I) bud
stage; (II) initial-flowering stage; (III) full-flowering stage; and (IV) end-flowering stage.
Figure 2. Total ionic chromatogram of volatile components emitted from flowers of L. pinceana in
different stages. (I) bud stage; (II) initial-flowering stage; (III) full-flowering stage; and (IV)
end-flowering stage.
As for the bud stage, 26 volatile compounds belonging to different chemical classes were identified:
benzenoids (51.61%), sesquiterpenes (44.41%), aliphatics (2.46%), and monoterpenes (1.48%). The most
abundant compound was paeonol, accounting for about 52% of the total GC peak area, followed by
δ-cadinene (10.98%), cubebol (5.48%), isoledene (5.45%), and cyclosativene (4.96%). By contrast,
Figure 1.
The morphological characteristics of L. pinceana flower in four different stages. (
I
) bud stage;
(II) initial-flowering stage; (III) full-flowering stage; and (IV) end-flowering stage.
Molecules 2016, 21, 531 5 of 10
2.2. Dynamic Changes of Scent Emission in Different Development Floral Stages
L. pinceana flowers were selected on the basis of their botanical characteristics to evaluate the
dynamic changes and diversity of floral volatiles according to different development stages: bud
stage, initial-flowering stage, full-flowering stage, and end-flowering stage (Figure 1). Table 1 and
Figure 2 show the distinct changes in scent composition and concentration across flowering stages.
Scent components were drastically emitted at the initial-flowering stage, and then declined gradually
at the full-flowering stage. The amount of VOCs at the bud stage and the end-flowering stage was
obviously lower than that at the initial-flowering stage. The emission pattern of L. pinceana flowering
stages was different from Cananga odorata [23], Vanda Mimi Palmer [24], and Hosta flowers [25] of
which the fragrance ingredients were drastically emitted at the full-flowering stage and decreased
greatly afterwards. These results showed that the emissions at different flower stages evidently
differed. Investigation of the spatial and temporal patterns of gene expression has provided new
information on the factors regulating the emission of plant volatile compounds [26].
Figure 1. The morphological characteristics of L. pinceana flower in four different stages. (I) bud
stage; (II) initial-flowering stage; (III) full-flowering stage; and (IV) end-flowering stage.
Figure 2. Total ionic chromatogram of volatile components emitted from flowers of L. pinceana in
different stages. (I) bud stage; (II) initial-flowering stage; (III) full-flowering stage; and (IV)
end-flowering stage.
As for the bud stage, 26 volatile compounds belonging to different chemical classes were identified:
benzenoids (51.61%), sesquiterpenes (44.41%), aliphatics (2.46%), and monoterpenes (1.48%). The most
abundant compound was paeonol, accounting for about 52% of the total GC peak area, followed by
δ-cadinene (10.98%), cubebol (5.48%), isoledene (5.45%), and cyclosativene (4.96%). By contrast,
Figure 2.
Total ionic chromatogram of volatile components emitted from flowers of L. pinceana
in different stages. (
I
) bud stage; (
II
) initial-flowering stage; (
III
) full-flowering stage;
and (IV) end-flowering stage.
As for the bud stage, 26 volatile compounds belonging to different chemical classes were identified:
benzenoids (51.61%), sesquiterpenes (44.41%), aliphatics (2.46%), and monoterpenes (1.48%). The
Molecules 2016,21, 531 6 of 10
most abundant compound was paeonol, accounting for about 52% of the total GC peak area, followed
by
δ
-cadinene (10.98%), cubebol (5.48%), isoledene (5.45%), and cyclosativene (4.96%). By contrast,
relative content of (E)-
β
-ocimene (0.87%), (
´
)-
β
-cadinene (2.34%), cubebol (5.48%), and cubenol (1.02%)
at the bud stage were higher than that at the other stages of flower development.
As for the initial-flowering stage, 26 volatile compounds belonging to different chemical classes
were identified: benzenoids (85.88%), sesquiterpenes (13.37%), aliphatics (0.53%), and monoterpenes
(0.15%). The most abundant compound was paeonol, accounting for about 83% of the total GC
peak area, followed by (E,E)-
α
-farnesene (3.89%), methyl salicylate (2.85%), and
δ
-cadinene (2.61%).
On the other hand,
relative content of nonanoic acid, ethyl ester (0.01%) and methyl salicylate (2.85%)
in the initial-flowering stage were significantly lower than that in the end-flowering stage, but was
higher than that in the bud stage and the full-flowering stage. Relative content of hexyl caprylate was
significantly lower than that in the other flower development stages.
As for the full-flowering stage, 32 volatile compounds belonging to different chemical classes were
identified: benzenoids (80.05%), sesquiterpenes (16.79%), monoterpenes (1.63%), and aliphatics (1.46%).
The most abundant compound was paeonol, accounting for about 80% of the total GC peak area,
followed by
γ
-muurolene (5.86%), (E,E)-
α
-farnesene (4.90%), and cyclosativene (2.07%). In addition,
relative content of
β
-ylangene (0.09%) and
γ
-muurolene (5.86%) in the full-flowering stage were higher
than that in the other stages of flower development.
As for the end-flowering stage, 32 volatile compounds belonging to different chemical classes were
identified: benzenoids (75.38%), sesquiterpenes (13.91%), monoterpenes (7.91%), and aliphatics (2.81%).
The most abundant compound was paeonol, accounting for about 70% of the total GC peak area,
followed by methyl salicylate (4.81%), (E,E)-
α
-farnesene (4.75%), and 3-carene (3.73%). By contrast,
relative content of monoterpenes in the end-flowering stage were significantly higher than that in the
other stages of flower development, including (1S)-2,6,6-trimethylbicyclo[3.1.1]hept-2-ene (0.45%),
α
-pinene (2.11%), 3-carene (3.73%), and
α
-santoline alcohol (0.32%). Relative content of nonanoic acid,
ethyl ester (0.02%) and benzyl benzoate (0.78%) in the end-flowering stage were significantly higher
than that in the other stages of flower development.
The Bray-Curtis similarity index is a statistic used for comparing the similarity of two samples [
27
].
The mean Bray-Curtis similarity index was 74.57%
˘
11.53% (range: 61.81%~90.23%, n= 12, Table 2).
The initial-flowering stage was more similar to the full-flowering stage (BCS = 90.23%) than to the
end-flowering stage (BCS = 83.59%), and was largely dissimilar to the bud stage (BCS = 62.77%).
Across all the flower-life stages, the bud stage was distinctly dissimilar to the full-flowering stage
(BCS = 61.81%).
Variations of the volatile compositions were apparently involved in the maturity
stages of flower. The same phenomena are also observed in other plants, such as the flowers of Ocimum
citriodorum [
28
], Penstemon digitalis [
29
], and Cananga odorata [
23
]. In this study, the highest diversity of
floral volatiles was detected at the third and later periods of the flower development. Meanwhile, the
richness of volatile compounds showed an unimodal pattern between the number of VOCs and times
of flower development.
Table 2.
The Bray-Curtis similarity index (%) among different stages of L. pinceana flower development.
(I) bud stage; (II) initial-flowering stage; (III) full-flowering stage; and (IV) end-flowering stage.
I II III IV
I100
II 62.77 100
III 61.81 90.23 100
IV 65.32 83.59 83.71 100
To identify which volatiles contributed the most to the differences among the four flower stages
and to display the differences in a more visually appealing manner, the data on 39 volatile compounds
identified in L. pinceana at a full life-flower scale were analyzed by using principal component
Molecules 2016,21, 531 7 of 10
analysis (PCA). The first three components of PCA explained 37.43%, 26.34%, and 23.15% of the
variation, explaining ~87% of combined variance (Figure 3). Hereinto, volatiles that had high
positive scores on PC 1 included (
´
)-
β
-cadinene,
δ
-cadinene, cadine-1,4-diene, cubenol, cubebol,
isoledene, caryophyllene and
α
-cubebene, which were highly positively related to the bud stage
and the initial-flowering stage. Volatiles with high positive scores on PC 2 comprised
β
-ylangene,
γ-muurolene, unknown-1, unknown-2 and perilla alcohol, which were positively correlated with the
full-flowering stage and initial-flowering stage. Volatiles with high positive scores on PC 3 included
cis-verbenol,
α
-acorenol, (3E,5Z)-1,3,5-undecatriene and cedrol, which were negatively correlated
with the full-flowering stage. The remaining 22 volatiles were composed of common components,
megastigma-4,6(E),8(E)-triene, cyclosativene and 4-epi-cubebol. The principal component plots did not
overlap amongst the four flower developmental stages indicated that the composition and its relative
content of floral scent differed throughout the whole floral development, and the initial-flowering
stage was recommended the best harvesting time when the high level of VOCs and essential oil are
a concern.
Molecules 2016, 21, x 7 of 10
initial-flowering stage. Volatiles with high positive scores on PC 2 comprised β-ylangene,
γ-muurolene, unknown-1, unknown-2 and perilla alcohol, which were positively correlated with the
full-flowering stage and initial-flowering stage. Volatiles with high positive scores on PC 3 included
cis-verbenol, α-acorenol, (3E,5Z)-1,3,5-undecatriene and cedrol, which were negatively correlated
with the full-flowering stage. The remaining 22 volatiles were composed of common components,
megastigma-4,6(E),8(E)-triene, cyclosativene and 4-epi-cubebol. The principal component plots
did not overlap amongst the four flower developmental stages indicated that the composition and
its relative content of floral scent differed throughout the whole floral development, and the
initial-flowering stage was recommended the best harvesting time when the high level of VOCs and
essential oil are a concern.
(a) (b)
Figure 3. Principal component plot (PC1 vs. PC2 plots (a) and PC1 vs. PC3 plots (b)) for L. pinceana at
different stages of growth, showing correlations with volatiles (numbers correspond to those in Table 1).
(I) bud stage; (II) initial-flowering stage; (III) full-flowering stage; and (IV) end-flowering stage.
3. Materials and Methods
3.1. Plant Materials
Fifteen fresh early flowering inflorescences from three L. pinceana plants (separation between plants
more than 100 m, five inflorescences per plant) were collected from the Nujiang Lisu Autonomous
Prefecture, Yunnan Province (25°58′N; 98°48′E) during their flourishing florescence on 10 November
2014, and inserted into deionized water before transported to the Research Institute of Resources
Insects, Chinese Academy of Forestry (RIRICAF) in Kunming. Subsequently, the inflorescences were
preserved at room temperature (25 ± 1 °C). The flowers were classified into four groups [23] according
to their botanical characteristics (Figure 1): (I) bud stage: buds complete closed, two or three days
before full bloom; (II) initial-flowering stage: semi-open petal, one day before full bloom; (III)
full-flowering stage: completely open petals, observable pistils and stamens; and (IV) end-flowering
stage: petals and calyxes withered, five or six day after full bloom.
3.2. Method
Volatile compounds of a complete flower was trapped immediately into a 20 mL capped
solid-phase microextraction vial at 8:00–11:00 a.m. Three replicate experiments (five flowers from
five inflorescences per replicate) were conducted using different plants randomly and the results
were means of three tests (fifteen flowers).
SPME analysis was performed by 100 μm polydimethylsiloxane (PDMS) SPME fiber which was
highly sensitive in the analysis of scent components equipped with a manual SPME holder. After the
equilibration time, the fiber was exposed to the headspace of the capped vial to absorb volatile
compounds for 40 min at room temperature (25 ± 1 °C). The fiber was conditioned in the GC
injection port for 1 h at 250 °C before it was used for the first time. In addition, the empty capped vial
Figure 3. Principal component plot (PC1 vs. PC2 plots (a) and PC1 vs. PC3 plots (b)) for L. pinceana at
different stages of growth, showing correlations with volatiles (numbers correspond to those in Table 1).
(I) bud stage; (II) initial-flowering stage; (III) full-flowering stage; and (IV) end-flowering stage.
3. Materials and Methods
3.1. Plant Materials
Fifteen fresh early flowering inflorescences from three L. pinceana plants (separation between
plants more than 100 m, five inflorescences per plant) were collected from the Nujiang Lisu
Autonomous Prefecture, Yunnan Province (25
˝
58
1
N; 98
˝
48
1
E) during their flourishing florescence
on 10 November 2014, and inserted into deionized water before transported to the Research Institute
of Resources Insects, Chinese Academy of Forestry (RIRICAF) in Kunming. Subsequently, the
inflorescences were preserved at room temperature (25
˘
1
˝
C). The flowers were classified into
four groups [
23
] according to their botanical characteristics (Figure 1): (I) bud stage: buds complete
closed, two or three days before full bloom; (II) initial-flowering stage: semi-open petal, one day before
full bloom; (III) full-flowering stage: completely open petals, observable pistils and stamens; and (IV)
end-flowering stage: petals and calyxes withered, five or six day after full bloom.
3.2. Method
Volatile compounds of a complete flower were trapped immediately into a 20 mL capped
solid-phase microextraction vial at 8:00–11:00 a.m. Three replicate experiments (five flowers from five
inflorescences per replicate) were conducted using different plants randomly and the results were
means of three tests (fifteen flowers).
Molecules 2016,21, 531 8 of 10
SPME analysis was performed by 100
µ
m polydimethylsiloxane (PDMS) SPME fiber which
was highly sensitive in the analysis of scent components equipped with a manual SPME holder.
After the
equilibration time, the fiber was exposed to the headspace of the capped vial to absorb
volatile compounds for 40 min at room temperature (25
˘
1
˝
C). The fiber was conditioned in the GC
injection port for 1 h at 250
˝
C before it was used for the first time. In addition, the empty capped vial
was used as the blank control. A gas chromatograph-mass spectrometer (TRACE GC Ultra/ITQ900,
Thermo Fisher Scientific, Waltham, MA, USA) coupled with a DB-5MS capillary column (5% diphenyl
cross-linked 95% dimethylpolysiloxane, 30 m
ˆ
0.25 mm i.d., 0.25
µ
m film thickness. Agilent J & W
Scientific, Folsom, CA, USA) were used for the GC-MS analysis. Follow the SPME analysis, the fiber
with volatile compounds was exposed in the GC injector port for desorption at 260
˝
C for 1 min in
the splitless mode. Helium was used as a carrier gas at a constant flow-rate of 1 mL/min. The oven
temperature was programmed at 40 ˝C for 2 min, increasing 6 ˝C/min to 130 ˝C and then increasing
15
˝
C/min to 280
˝
C for 5 min. The split and splitless injection port were held at 260
˝
C and 200
˝
C in
split mode at a split ratio of 1:10. The temperature of the transfer line and the ion source were 200 ˝C
and 250
˝
C. The ionization potential of mass selective detector was 70 eV and the scan range was
50–650 amu.
3.3. Data Analysis
Identification of the volatile compounds was based on comparison of their mass spectra with
NIST08 database through Software TF Xcalibur 2.1.0 (Thermo Fisher Scientific). Volatile compounds
were identified on the basis of their linear retention index (LRI) and by comparing their mass
spectra with a computerized MS-database using NIST 2008 library and published data (Pherobase,
http://www.pherobase.com/; NIST, http://webbook.nist.gov/chemistry/; The LRI and Odour
Database, http://www.odour.org.uk).
LRI were calculated by the use of a series of n-alkane standards (C6–C19) (Accu Standard, New
Haven, CT, USA). It is defined as Equation (1):
LRI “100 ˆn`100 ˆ ptx´tnq
tn`1´tn(1)
Peak areas were normalized as percentage and used to determine the relative amounts of the
volatiles. The normalization method from the Equation (2):
Relative content p%q “ area under peak
total peak area ˆ100 (2)
The data were expressed as mean
˘
standard deviation (SD) of triplicate measurements. One-way
analysis of variance (ANOVA) with Tukey’s test in SPSS software was used to assess differences in
aroma compounds among four different stages of L. pinceana flower development. Volatile compounds
identified at a full life-flower scale were analyzed by using principal component analysis (PCA) and
Bray-Curtis similarity (BCS). PCA and BCS were carried out using PC-ORD for Windows (Version 5.0;
MjM Software, Gleneden Beach, OR, USA).
4. Conclusions
The present investigation showed that 39 VOCs were identified in all flower-life stages of
L. pinceana, amongst them, 26 at bud stage, 26 at initial-flowering stage, 32 at full-flowering stage,
and 32 at end-flowering stage. Benzenoids were the most abundant amongst floral scent compounds.
The amount of floral scent emission offered tendency of ascending first and descending in succession,
reaching peak level at initial-flowering stage. The highest diversity of floral volatile was detected at
the third and later periods of flower developmental stage. The odour evidently differed in composition
and its relative content in the four flower developmental stages. The second flower developmental
Molecules 2016,21, 531 9 of 10
stage was recommended as the best harvesting time if a high level of VOCs and essential oil are of
interest. L. pinceana could serve as beneficial houseplant in the future, besides as fragrant ornamental
according to the VOCs emitted from the flowers. Furthermore, L. pinceana has a promising prospects for
development as an essential oil source owing to the many medicinal properties of the main compounds
of the floral scent.
Acknowledgments:
We thank Wenwen Zhang, Yanlong Yang and Shuaifeng Li for assistance in data analysis. This
work was financially supported by Special Fund for Forest Scientific Research in the Public Welfare (201404705),
Technology Innovation Talent Project of Yunnan Province and Applied Basic Research Project of Yunnan Province
(2010ZC089).
Author Contributions:
Y.-Y.L., H.M., and Z.-H.L. conceived and designed the experiments; Y.-Y.L. and T.-Q.L.
performed the experiment; Y.-Y.L. and Y.-M.W. analyzed the data; X.-X.L. and Z.-H.S. contributed materials and
performed research; Y.-Y.L. and H.M. wrote the paper. All authors read and approved the final manuscript.
Conflicts of Interest: The authors declare no conflict of interest.
References
1.
Zhou, W.; Barrett, S.C.H.; Wang, H.; Li, D.-Z. Reciprocal herkogamy promotes disassortative mating in a
distylous species with intramorph compatibility. New Phytol. 2015,206, 1503–1512. [CrossRef] [PubMed]
2.
Ma, H.; Wang, Y.; Li, Z.H.; Wan, Y.M.; Liu, X.X.; Liang, N. A study on the breeding system of Luculia pinceana.
Forest Res. 2009,22, 373–378.
3.
Zhou, W.; Wang, H.; Li, D.Z.; Yang, J.B.; Zhou, W. Isolation and characterization of 13 microsatellite loci from
Luculia pinceana (Rubiaceae), a typical distylous species. Hortscience 2010,45, 840–841.
4.
Zhou, W.; Barrett, S.C.H.; Wang, H.; Li, D.Z. Loss of floral polymorphism in heterostylous Luculia pinceana
(Rubiaceae): A molecular phylogeographic perspective. Mol. Ecol.
2012
,21, 4631–4645. [CrossRef] [PubMed]
5.
Wan, Y.M.; Li, Z.H.; Ma, H.; Liu, X.X. Microsporogenesis and male gametophyte development of long-style
flower of Luculia pinciana (Rubiaceae). Acta Bot. Boreal-Occident. Sin. 2014,34, 1570–1575.
6.
Murray, B.G. Heterostyly and pollen-tube interactions in Luculia gratissima (Rubiaceae). Ann. Bot.
1990
,65,
691–698.
7.
Kang, W.Y.; Du, Z.Z.; Yang, X.S.; Hao, X.J. A new triterpene from Luculia pinciana Hook. J. Asian Nat. Prod. Res.
2005,7, 91–94. [CrossRef] [PubMed]
8.
Jo, H.; Rodiek, S.; Fujii, E.; Miyazaki, Y.; Park, B.J.; Ann, S.W. Physiological and psychological response to
floral scent. Hortscience 2013,48, 82–88.
9.
Dudareva, N.; Pichersky, E. Metabolic engineering of plant volatiles. Curr. Opin. Biotech.
2008
,19, 181–189.
[CrossRef] [PubMed]
10.
Knudsen, J.T.; Eriksson, R.; Gershenzon, J.; Stahl, B. Diversity and distribution of floral scent. Bot. Rev.
2006
,
72, 1–120. [CrossRef]
11.
Flavornet and Human Odor Space. Available online: http://www.flavornet.org/flavornet.html (accessed on
22 February 2016).
12.
Kang, W.Y.; Wang, J.M.; Ji, Z.Q. Flavonoids in Luculia pinceana.Chem. Nat. Compd.
2008
,44, 644–645.
[CrossRef]
13.
Kim, H.K.; Tak, J.H.; Ahn, Y.J. Acaricidal activity of paeonia suffruticosa root bark-derived compounds
against dermatophagoides farinae and dermatophagoides pteronyssinus (Acari: Pyroglyphidae).
J. Agric. Food Chem. 2005,52, 7857–7861. [CrossRef] [PubMed]
14.
Huang, T.J.; Hong, C.; Liang, Y.C.; Lin, H.H.; Horng, J.C.; Kuo, Y.C.; Chen, C.W.; Tsai, F.Y.; Yen, S.C.; Chou, S.C.
Design, synthesis, and bioevaluation of paeonol derivatives as potential anti-HBV agents.
Eur. J. Med. Chem.
2015,90, 428–435. [CrossRef] [PubMed]
15.
Turkez, H.; Togar, B.; Stefano, A.D.; Taspınar, N.; Sozio, P. Protective effects of cyclosativene on H
2
O
2
-induced
injury in cultured rat primary cerebral cortex cells. Cytotechnology 2014,67, 299–309. [CrossRef] [PubMed]
16.
Rasoarivelo, S.T.R.; Grougnet, R.; Verite, P.; Lecsoe, M.; Butel, M.J.; Tillequin, F.; Guillou, C.R.; Deguin, B.
Chemical composition and antimicrobial activity of the essential oils of Anthospermum emirnense and
Anthospermum perrieri (Rubiaceae). Chem. Biodivers. 2011,8, 145–154. [CrossRef] [PubMed]
17.
Setzer, W.N.; Noletto, J.A.; Lawton, R.O. Chemical composition of the floral essential oil of Randia matudae
from Monteverde, Costa Rica. Flavour Frag. J. 2006,21, 244–246. [CrossRef]
Molecules 2016,21, 531 10 of 10
18. Kaiser, R. Scents from rain forests. Chimia 2000,54, 346–363.
19.
Vieira, R.C.; Delprete, P.G.; Leitao, G.G.; Leitao, S.G. Anatomical and chemical analyses of leaf secretory
cavities of Rustia formosa (Rubiaceae). Am. J. Bot. 2001,88, 2151–2156. [CrossRef] [PubMed]
20.
Andersson, S.; Nilsson, L.A.; Groth, I.; Bergstrom, G. Floral scents in butterfly-pollinated plants: Possible
convergence in chemical composition. Bot. J. Linn. Soc. 2002,140, 129–153. [CrossRef]
21.
Meng, X.; Wang, Z.Y.; Lv, H. Constituents and bacteriostatic activity of volatile matter from four flower plant
species. Indian J. Agric. Res. 2010,44, 157–167.
22.
Stashenko, E.E.; Martinez, J.R.; Cardenas-Vargas, S.; Saavedra-Barrera, R.; Duran, D.C. Gc-ms study of
compounds isolated from Coffea arabica flowers by different extraction techniques. J. Sep. Sci.
2013
,36,
2901–2914. [CrossRef] [PubMed]
23.
Qin, X.W.; Hao, C.Y.; He, S.Z.; Wu, G.; Tan, L.H.; Xu, F.; Hu, R.S. Volatile organic compound emissions from
different stages of Cananga odorata flower development. Molecules
2014
,19, 8965–8980. [CrossRef] [PubMed]
24.
Mohd-Hairul, A.R.; Namasivayam, P.; Lian, G.E.C.; Abdullah, J.O. Terpenoid, benzenoid, and
phenylpropanoid compounds in the floral scent of Vanda Mimi Palmer. J. Plant Biol.
2010
,53, 358–366.
[CrossRef]
25.
Liu, Q.; Sun, G.; Wang, S.; Lin, Q.; Zhang, J.; Li, X. Analysis of the variation in scent components of Hosta
flowers by HS-SPME and GC–MS. Sci. Hortic. 2014,175, 57–67. [CrossRef]
26.
Dudareva, N.; Pichersky, E.; Gershenzon, J. Biochemistry of plant volatiles. Plant Physiol.
2004
,135, 1893–1902.
[CrossRef] [PubMed]
27.
Yoshioka, P.M. Misidentification of the bray-curtis similarity index. Mar. Ecol. Prog. Ser.
2008
,368, 309–310.
[CrossRef]
28.
Al-Kateb, H.; Mottram, D.S. The relationship between growth stages and aroma composition of lemon basil
Ocimum citriodorum vis. Food Chem. 2014,152, 440–446. [CrossRef] [PubMed]
29.
Burdon, R.C.F.; Raguso, R.A.; Kessler, A.; Parachnowitsch, A.L. Spatiotemporal floral scent variation of
Penstemon digitalis.J. Chem. Ecol. 2015,41, 641–650. [CrossRef] [PubMed]
Sample Availability: Samples of the compounds are not available from the authors.
©
2016 by the authors; licensee MDPI, Basel, Switzerland. This article is an open access
article distributed under the terms and conditions of the Creative Commons Attribution
(CC-BY) license (http://creativecommons.org/licenses/by/4.0/).
Available via license: CC BY
Content may be subject to copyright.
... The floral fragrance is an essential trait for plants to induce insect pollination, drive away herbivores or resist pathogens [1,2]. It is also critical for ornamental plants to positively affect people's health and mood through their pleasant scents [3]. Even though floral fragrance has important scientific and economic significance, flower-breeding goals used to be concentrated on flower color and shape, resulting in quite a few cultivated flowers have gradually lost their fragrance [4]. ...
... There are many factors to be considered when investigating floral scents, including scent emission by oil secretory cells in different floral parts and how this varies according to flowering stages. Studies in many fragrant plants such as crabapple [12], Luculia pinceana [3] and Cananga odorata [13] have shown that the temporal patterns of odorant emission from flowers are comparable, while studies in Protea [14], Hosta [15] and Dianthus inoxianus [16] have shown that there are usually a variety of spatial patterns. Moreover, the distribution of the oil cells in flower organs has a significant effect on floral scent production [17], as volatile compounds are synthesized in the oil cells and are immediately released and disperse [6,18]. ...
... Spatiotemporal variation in floral scent emission has biological significance in mediating pollinator attractiveness [14]. Flowers usually start to produce fragrance when they are ready to spread and receive pollen to maximize pollination opportunities [3,12,13,37]. This seemed to occur in M. crassipes as well, as emitted scent components were drastically increased at the stage of full bloom in all isolated floral parts. ...
Analysis of Aroma Volatiles from Michelia crassipes Flower and Its Changes in Different Flower Organs during Flowering
Article
Full-text available
  • Mar 2023
Michelia crassipes is a great ornamental plant, the flowers of which have high economic value. In this study, we employed headspace solid-phase microextraction (HS–SPME) combined with gas chromatography high-resolution mass spectrometry (GC–HRMS) for the first time to identify the volatile compounds emitted from different organs of M. crassipes flowers at different flowering stages. M. crassipes flower odor comprises 69 volatile compounds that are dominated by terpenes constituting 84% of collected volatiles. It was found that α-guaiene, β-caryophyllene and germacrene B had the highest relative amounts, while ethyl 3-methyl valerate, methyl benzoate and β-damascone had the highest odor activity values (OAVs). This contributed to the complex fruity, woody and floral aromas of M. crassipes. Total odor emission increased along the flower blooming, which was most abundant in the pistil followed by tepals and stamens. Paraffin sections of M. crassipes flower organs showed the highest density of oil secretory cells in the pistil at the full flowering stage, which was positively correlated with total odor release. The scent of the pistil and tepals was characterized by terpenes, whereas stamens was characterized by benzenoids. We suggest that the benzenoids in stamens might contribute to pollinator attraction in M. crassipes.
View
... p-value = +0.1305). Hydrocarbon sesquiterpene results are similar to those found by Li et al. [38] from Luculia pinceana flower whose sesquiterpene content was much higher in the bud stage (44.41%) and significantly dropped during flower development: at 13.37%, 16.79%, and 13.91%, respectively, for SD2, SD3 and SD4. ...
... The only nitrogenous compound identified in this study, 2-Phenylnitroethane is exclusively presently on the two mature stages, SD4 and SD5 (0.04%-0.14%), in agreement with previous study [3]. On the other hand, relative content of δ-cadinene, cubebol, and cubenol at the bud stage were higher than that at the other stages of flower development, which is suitable with the results obtained by Li et al. [38] on Luculia pinceana flower. Figure 6 below shows the signature of total volatile compounds characterized by GC-MS. ...
... Across all the flower-life stages, the bud stage is distinctly dissimilar to the four full-flowering stages. Variations of the volatile compositions were also apparently involved in the maturity stages of flower from Luculia pinceana [38]. The same phenomena are observed in other plants, such as the flowers of Penstemon digitalis [43]. ...
Effect of Flower Development Stages on the Dynamics of Volatile Compounds in Ylang-Ylang (Cananga odorata) Essential Oil
Article
Full-text available
  • Oct 2022
Several abiotic factors influence the chemical composition of essential oils. Understanding these factors is an important step in developing quality products that meet market demands. This research work aims to study the chemical composition of the essential oils of ylang-ylang (Cananga odorata, forma genuina) according to the maturity of flowers. The volatile compounds of ylang-ylang flowers from Reunion Island were extracted by hydrodistillation and the samples were analyzed by high resolution gas chromatography coupled with mass spectrometry (GC-MS) allowing for the identification of 70 volatile compounds. The chemical composition of the essential oils extracted from the flowers at 5 different stages of development varies both qualitatively and quantitatively. The volatile compounds observed belong to 4 chemical groups which are esters, alcohols, terpenes, and ether-oxides. The synthesis of light oxygenated compounds is largely the predominant chemical subgroup in all stages of development. Their relative content is considerably increased during flower ripening with a peak concentration in stage 4 (SD4). The highest concentrations of non-terpene esters and heavy oxygenated compounds are found in stages 1 (SD1) and (SD5), respectively, while no chemical subgroup is dominant in the intermediate stages 2 (SD2) and (SD3). The dynamics of volatile compounds have also been studied. This study established that the stage of development of ylang-ylang flowers significantly influences the dynamics of volatile compounds in the extracted essential oils. Total oxygenated compounds that are highly odoriferous in essential oils increase progressively and significantly with flower maturity, unlike hydrocarbon terpenes, which are less valuable in terms of their contribution to the fragrance and following opposite kinetics; suggesting that odoriferous properties increase with the development of the flower, with a higher intensity at SD4.
View
... Luculia pinceana Hook., which belongs to the genus Luculia in Rubiaceae, is distinguished by its exceptionally long flowering period, elegant colouration, dense flower clusters, large inflorescences, and strong fragrance [1,2]. Moreover, all the species within the genus Luculia are characterized by their typical distyly. ...
Comparison of the morphological and physiological characteristics of diploid and tetraploid Luculia pinceana Hook
Article
Full-text available
  • Apr 2025
  • BMC PLANT BIOL
Background To explore the physiological and biochemical differences between different ploidy Luculia pinceana Hook. varieties and to obtain germplasm resources with excellent horticultural characteristics and strong resistance, we analysed and compared the morphological characteristics, photosynthetic properties, and physiological indices of diploid and tetraploid L. pinceana. Results (1) Tetraploid L. pinceana exhibited distinct polyploid characteristics, including a smaller plant, rounder, thicker, and darker green leaves, as well as coarser and longer leaf and stem hairs. Moreover, the flowers of tetraploids are relatively large, and the diameters of the flowers, the lengths of the corolla tubes and the lengths of the pistils are all extremely significantly greater than those of diploids. Compared with those of tetraploids, the leaf width and thickness of the diploid plants increased by 16.38% and 14.71%, respectively, whereas the leaf length, leaf area, and plant height decreased by 21.20%, 3.46%, and 54.86%, respectively. (2) The diurnal variation curve of photosynthesis in L. pinceana was unimodal, reaching a maximum value at approximately 10:00. Compared with diploid plants, tetraploid plants presented a significantly greater maximum net photosynthetic rate (Pmax), light saturation point (LSP), and light compensation point (LCP). (3) Compared with diploids, tetraploid leaves presented significantly greater activities of antioxidant enzymes, including superoxide dismutase (SOD, + 51.61%), peroxidase (POD, + 6226%), and catalase (CAT, + 211.66%). Additionally, the concentrations of osmolytes [soluble sugar (SS, + 80.11%), soluble protein (SP, + 63.49%), and proline (Pro, + 57.40%)] were markedly elevated. Conversely, the malondialdehyde (MDA) content was substantially decreased (-46.16%). Conclusion These results demonstrate that the tetraploid L. pinceana has greater ornamental value, fertility and resistance. It is an excellent breeding material for the germplasm resources of L. pinceana and provides a material basis for the cultivation of new varieties of L. pinceana.
View
... Higher levels of δ-Cadinene and α-Farnesene present in the CCO plausibly contributed to its aroma and antioxidant activity (Y. Li et al., 2016). Chamazulene was detected in ICO but was not found in the CCO. ...
Comparison between Indian and commercial chamomile essential oils: Chemical compositions, antioxidant activities and preventive effect on oxidation of Asian seabass visceral depot fat oil
Article
Full-text available
  • Feb 2025
Antioxidant properties of indigenous Indian (ICO) and commercial (CCO) chamomile essential oils (EOs) and their application in preventing lipid oxidation of fish oil were investigated. Solid-phase micro-extraction gas chromatography–mass spectrometry (SPME-GCMS) revealed dominant compounds to be α-bisabolol and chamazulene in ICO, while α-farnesene and δ-cadinene in CCO. Both EOs exhibited similar 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and oxygen radical absorbance capacity (ORAC) values but ICO showed superior effect in β-carotene/linoleic system. When applied in Asian seabass visceral depot fat oil (SVDFO), ICO (400 mg/L) significantly reduced peroxide values after 15 days (30°C) and slightly lowered thiobarbituric acid reactive substances and anisidine values. ICO (400 mg/L) showed comparable efficacy in preventing the oxidation of polyunsaturated fatty acids (PUFAs) to 200 mg/L butylated hydroxytoluene (BHT) within 0–12 days. Fourier Transform Infrared (FTIR) analysis confirmed preservation of PUFA double bonds by ICO. Therefore, chamomile EOs, especially ICO, could prevent lipid peroxidation in PUFA-rich oils.
View
... These secondary metabolites have been reported to play a role in flower development in Rosa damascena [44]. Others studied the volatile organic compounds emissions from the Luculia pinceana flower and found that these volatile organic compounds have been changed at different stages of flower development [50]. The PCA plot showed that the non-reproductive parts of the flowers showed similarities in the expression of metabolites while the reproductive parts such as Stamens (ST) and Pistil (PI) showed visible variance. ...
Metabolite changes during developmental transitions in Adonis amurensis Regel et Radde flowers: Insights from HPLC-MS analysis
Article
Full-text available
Adonis amurensis Regel et Radde is a remarkable and important spring ephemeral plant and gained considerable attention because of its remarkable medicinal properties. Extensive research has been conducted on its therapeutic applications, physical characteristics, flowering patterns, reproductive, cultural and molecular biology. However, there is a lack of comprehensive understanding regarding the metabolic changes associated with flower developmental stages. This study was designed to investigate the changes in metabolites and their interrelationships at five distinct developmental stages of A. amurensis flower: Flower Primordium (FP), Sepal Stage (SE), Perianth Primordium (PE), Stamens Stage (SE), and Pistil Stage (PI). High-performance liquid chromatography coupled with mass spectrometry (HPLC-MS) was utilized to investigate and characterize the metabolites associated with specific flower developmental stages. The various stages of flower development exerted a substantial influence on both the quantity and composition of metabolites present, signifying significant changes in the types and quantities of metabolites throughout the developmental progression of the flower. Metabolite Set Enrichment Analysis (MSEA) and annotation via the KEGG database highlighted enriched pathways such as flavonoid biosynthesis and plant hormone signal transduction, which are crucial for flower maturation. The highest number of differentially expressed metabolites was identified between the SE and PI stages, emphasizing a marked appreciation in metabolite expression linked to the development of reproductive organs. Key pathways such as flavonoid biosynthesis and plant hormone signal transduction were markedly enriched, underscoring their roles in flower maturation and potential pharmacological applications. Our research not only helps us in understanding the metabolomic dynamics during the flower development of A. amurensis but also emphasizes the potential pharmacological implication of stage-specific metabolites. Identifying these metabolites can help targeted bioprospecting and optimization of extraction methods to tackle the plant’s full therapeutic potential, particularly in the development of treatments for cardiac insufficiency, edema, and possibly cancer.
View
... During the flowering process, the release of floral scent is a dynamic process that changes continuously Kim et al., 2022). The concentrations of VOCs in flowers are closely related to flower maturity, and plants begin to release floral scents when they are ready (Li et al., 2016;Fan et al., 2019a). This study observed that both the composition and emission levels of volatile compounds varied with flower development. ...
Molecular mechanisms underlying floral fragrance in Camellia japonica ‘High Fragrance’: a time-course assessment
Article
Full-text available
  • Nov 2024
Camellia japonica ‘High Fragrance’ is a camellia hybrid known for its unique and intense floral scent. The current understanding of the dynamic changes in its fragrance and the underlying mechanisms are still limited. This study employed a combination of metabolomic and transcriptomic approaches to reveal the characteristics of the metabolites involved in the remarkable fragrance of this camellia and their biosynthetic mechanisms along three flower developmental stages (flower bud, initial bloom, and full bloom). Among the 349 detected volatile organic compounds (VOCs), the majority were terpenes (57, 16.33%) and esters (53, 15.19%). Of these, 136 VOCs exhibited differential accumulation over time. Transcriptomic data from floral organs at different flowering stages identified 56,303 genes, with 13,793 showing significant differential expression. KEGG enrichment analysis revealed 57, 91, and 33 candidate differential genes related to the biosynthesis of terpenes, phenylpropanoids, and fatty acid derivatives, respectively. This indicates that terpenes, esters, and their related synthetic genes might play a crucial role in the formation of ‘High Fragrance’ characteristics. During the entire flowering process, the majority of genes exhibited an elevated expression pattern, which correlated with the progressive accumulation of VOCs. Interestingly, the expression patterns of the differentially expressed genes in the mevalonate (MVA) and 2-C-methyl-D-erythritol 4-phosphate (MEP) pathways, associated with terpene synthesis, showed opposite trends. A transcriptional-metabolic regulatory network linking terpenoid compounds, related synthetic enzymes, and potential transcription factors could be outlined for ‘High Fragrance’ camellia, thus providing a theoretical basis for further exploring these events and breeding more fragrant camellias.
View
... The species and contents of volatiles in flowers vary with the plant species and flower development stages [15,33]. There are usually many kinds of VOCs in flowers in full bloom, and large amounts of volatiles are released [34]. ...
Metabolome and Transcriptome Combined Reveal the Main Floral Volatile Compounds and Key Regulatory Genes of Castanea mollissima
Article
Full-text available
  • Oct 2024
Chestnut (Castanea mollissima) is an economically important forest tree species, and its flowers possess functions such as repelling mosquitoes, killing bacteria, and clearing heat. However, the regulatory mechanisms of floral volatile organic compounds (VOCs) in chestnut are still unclear. This study analyzed the contents of major volatile compounds and related gene expression levels in chestnut flowers during the initial flowering stage (IFS) and full-flowering stage (FFS) using metabolomics and transcription techniques. In total, 926 volatile compounds were detected, mainly terpenes, heterocyclic compounds, and esters. Acetylenone, styrene, and β-pinene had contents that exceeded 5% in FFS chestnut flowers. In total, 325 differential metabolites between the IFS and FFS were significantly (p < 0.05) enriched in the biosynthetic pathways of sesquiterpenes and triterpenes, as well as the ethylbenzene metabolic pathway. In total, 31 differentially expressed genes (DEGs) were related to terpenoid biosynthesis. There were only two DEGs related to the ethylbenzene metabolic pathway. In summary, we identified the volatile components of chestnut flowers and analyzed the changes in the contents of major volatile compounds in the flowers and the expression patterns of the related genes. The research results are helpful for understanding the regulation of VOCs in chestnut flowers.
View
View
Impact of Climate Change on the Potential Geographical Distribution Patterns of Luculia pinceana Hook. f. since the Last Glacial Maximum
Article
Full-text available
  • Jan 2024
In this study, we utilized 76 natural distribution points and six environmental variables to establish a detailed species distribution prediction process for Luculia pinceana Hook. f. Our aim was to explore the potential distribution patterns of L. pinceana since the Last Glacial Maximum (LGM) and its response to climate change, providing a scientific basis for conservation strategies and the suitable introduction of its wild populations. This model enabled the prediction of L. pinceana’s geographical distribution patterns across five temporal phases: the LGM, the Mid-Holocene (MH), the present, and two future scenarios. Additionally, the model pinpointed the dominant environmental factors influencing these distribution patterns. The results indicate the following: (1) The temperature annual range (bio7), the minimum temperature of the coldest month (bio6), and the precipitation of the wettest month (bio13) are the dominant environmental factors that determine the distribution of L. pinceana. In areas where bio7 is less than 22.27 °C, bio6 is above 3.34 °C, and bio13 exceeds 307.65 mm, the suitability for L. pinceana is highest. (2) Under the current climatic conditions, the highly suitable area of L. pinceana accounts for 64 × 10⁴ km², which accounts for half of the total suitable area. The suitable habitats for L. pinceana are concentrated in Yunnan, Guizhou, Sichuan, Chongqing, Guangxi, southern Nyingchi in Tibet, and the coastal areas of South China. (3) During the LGM and the MH, the suitable habitats for L. pinceana were essentially consistent with the current scenarios, with no significant southward shift in distribution. This lack of a major southward migration during the LGM could be attributed to the species finding refuge in situ in mountainous areas. (4) Under various future emission scenarios, the suitable habitat area for L. pinceana is expected to experience significant expansion, generally shifting towards the northwest and higher latitudes. The anticipated global warming in the future is likely to provide more favorable conditions for the survival of L. pinceana. It is recommended that the introduction follows the direction of centroid migration, facilitated by vegetation management, and it has the ecological and economic benefits of L. pinceana to a greater extent.
View
Features of floral odor and nectar in the distylous Luculia pinceana (Rubiaceae) promote compatible pollination by hawkmoths
Article
Full-text available
  • Mar 2023
It is hypothesized that in heterostylous plant species, standardization of signals of floral attraction between different morphs is advantageous, encouraging flower visitors to switch between morphs. It remains unclear whether signals of floral attraction (floral odor and properties of nectar) are similar between morphs in distylous species pollinated by hawkmoths, and how these relate to hawkmoth behavior. We observed the behavior of visitors to distylous Luculia pinceana (Rubiaceae), collected and analyzed floral odor, and examined properties of nectar (volume, sugar concentration, and composition) of long-styled and short-styled morphs during the day and night. Pollinator responses to the floral scent were tested with a Y-tube olfactometer. We conducted diurnal and nocturnal pollination treatments and six other pollination treatments to test the importance of nocturnal pollinators and to examine the self-incompatibility system. A species of hawkmoth, Cechenena lineosa, was the effective pollinator. The floral odor was rich in methyl benzoate, and sucrose was dominant in the nectar. There were no significant differences between the two morphs in the methyl benzoate content or the properties of nectar. Flowers released more methyl benzoate and secreted larger volumes of nectar with lower sugar concentration at night than during the day. The hawkmoth had a significant preference for methyl benzoate. Luculia pinceana was partially self-incompatible and relied on nocturnal pollinators for reproductive success. This study verifies that floral attraction signals are consistent between different morphs in this distylous species, promoting compatible pollination, and the features and the diel pattern of these signals between day and night are adapted to hawkmoth behavior.
View
Spatiotemporal Floral Scent Variation of Penstemon digitalis
Article
Full-text available
  • Jul 2015
  • J CHEM ECOL
Variability in floral volatile emissions can occur temporally through floral development, during diel cycles, as well as spatially within a flower. These spatiotemporal patterns are hypothesized to provide additional information to floral visitors, but they are rarely measured, and their attendant hypotheses are even more rarely tested. In Penstemon digitalis, a plant whose floral scent has been shown to be under strong phenotypic selection for seed fitness, we investigated spatiotemporal variation in floral scent by using dynamic headspace collection, respectively solid-phase microextraction, and analyzed the volatile samples by combined gas chromatography-mass spectrometry. Total volatile emission was greatest during flowering and peak pollinator activity hours, suggesting its importance in mediating ecological interactions. We also detected tissue and reward-specific compounds, consistent with the hypothesis that complexity in floral scent composition reflects several ecological functions. In particular, we found tissue-specific scents for the stigma, stamens, and staminode (a modified sterile stamen common to all Penstemons). Our findings emphasize the dynamic nature of floral scents and highlight a need for greater understanding of ecological and physiological mechanisms driving spatiotemporal patterns in scent production.
View
Isolation and Characterization of 13 Microsatellite Loci from Luculia pinceana (Rubiaceae), a Typical Distylous Species
Article
Full-text available
  • May 2010
Luculia pinceana Hook. (Rubiaceae) is a typical distylous species with dimorphic and long-styled monomorphic populations. Within this study, we developed 13 microsatellite markers from L. pinceana using a modified biotin-streptavidin capture method. Polymorphism of each locus was assessed in 30 individuals from four dimorphic populations and one monomorphic population. The average allele number of these microsatellites was 4.153 per locus ranging from three to seven. The observed and expected heterozygosities were from 0.040 to 0.840 and from 0.571 to 0.769, respectively. Additionally, all 13 identified microsatellite markers were successfully amplified in its related species, L. yunnanensis, 10 of which showed polymorphism. These microsatellite markers could provide a useful tool for further study of the breeding system and the population genetic structure in this species and within other Luculia species.
View
Reciprocal herkogamy promotes disassortative mating in a distylous species with intramorph compatibility
Article
Full-text available
Mating patterns in heterostylous species with intramorph compatibility have the potential to deviate from symmetrical disassortative mating owing to ecological and reproductive factors influencing pollen dispersal. Here, we investigate potential and realized patterns of mating in distylous Luculia pinceana (Rubiaceae), a species with intramorph compatibility. Our analysis provides an opportunity to test Darwin's hypothesis that reciprocal herkogamy promotes disassortative pollen transfer. We combined measurements of sex-organ reciprocity and pollen production to predict potential pollen transfer and mating patterns in a population from SW China. Marker-based paternity analysis was then used to estimate realized patterns of disassortative and assortative mating at the individual and floral morph levels. Both potential and realized mating patterns indicated a significant component of disassortative mating, satisfying theoretical conditions for the maintenance of floral dimorphism. Levels of assortative mating (37.7%) were significantly lower than disassortative mating (62.3%), but numerous offspring resulting from intramorph mating were detected in the majority of maternal seed families in both floral morphs. Our results provide empirical support for Darwin's cross-promotion hypothesis on the function of reciprocal herkogamy, but indicate that in most heterostylous species strong diallelic incompatibility may be a general requirement for complete disassortative mating. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.
View
Volatile Organic Compound Emissions from Different Stages of Cananga odorata Flower Development
Article
Full-text available
Headspace-solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) was used to identify the volatile organic compounds (VOCs) of the different flower development stages of Cananga odorata for the evaluation of floral volatile polymorphism as a basis to determine the best time of harvest. Electronic nose results, coupled with discriminant factor analysis, suggested that emitted odors varied in different C. odorata flower development stages, including the bud, display-petal, initial-flowering, full-flowering, end-flowering, wilted-flower, and dried flower stages. The first two discriminant factors explained 97.52% of total system variance. Ninety-two compounds were detected over the flower life, and the mean Bray–Curtis similarity value was 52.45% among different flower development stages. A high level of volatile polymorphism was observed during flower development. The VOCs were largely grouped as hydrocarbons, esters, alcohols, aldehydes, phenols, acids, ketones, and ethers, and the main compound was β-caryophyllene (15.05%–33.30%). Other identified compounds were β-cubebene, d-germacrene, benzyl benzoate, and α-cubebene. Moreover, large numbers of VOCs were detected at intermediate times of flower development, and more hydrocarbons, esters, and alcohols were identified in the full-flowering stage. The full-flowering stage may be the most suitable period for C. odorata flower harvest.
View
Heterostyly and Pollen-tube Interactions in Luculia gratissima (Rubiaceae)
Article
  • Jun 1990
Observations on the floral biology of Luculia gratissima (Rubiaceae) showed that this species is distylous with complementary positioning of anthers and stigmas in the two floral forms. Unusual features of distyly in this species include the larger size of the corolla, the stigma surface and the stigmatic papillae in the thrum flowers compared to the pin ones. Stigmatic surfaces have similar secretions but they appear more copious in thrum than pin. The floral dimorphism was accompanied by a very effective self-incompatibility system and no seed was set on selfing. Seed number per capsule on crossing was significantly greater in thrum flowers compared to pin. Incompatible pollen tubes were inhibited within 24 h at the base of the stigma/top of the style in both morphs. Amputation of this region of the gynoecium removed the self-incompatibility reaction in thrum but not pin flowers. Pollination with a mixture of compatible and incompatible pollen and sequential pollination with self followed by cross pollen showed that there were interactions between the two types of pollen tube. The presence of compatible tubes was found to cause the excessive swelling of the pollen-tube tip of the incompatible ones. The incompatible tubes did not appear to have any effect on the growth of compatible ones.
View
A study on the breeding system of Luculia pinciana
Article
  • Jun 2009
Breeding system is theoretically considered as a principal factor which has the most apparent effects on plant evolution and population genetic structure. This paper presents the floral traits, pollen viability, stigma receptivity, pollen-ovule ratio, out-crossing index, fruit sets under a serious pollination treatments, and pollinating observation of Luculia pinciana. The result showed that the number of inflorescence per pin plant was significantly higher, while the corolla tube and the stigma lobe of the pin flower were significantly shorter in length. The pollen viability of L. pinciana peaked around 70% after the anther loosed pollen for 8 h, and its stigma had peroxidase activity from the early phase of the anther loosing pollen until the end of flowering. The pollen-ovule ratio of pin flower and thrum flower was 1 641.7 ±365.84 and 947.3 ±194.84 respectively and both of their out-crossing index was 3. Combining with the result of emasculation, bagging, artificial pollination and pollinating observation, it was concluded that L. pincina should be anthophilous flower plant under natural condition. The compatible pollen of pin flower and thrum flower was respectively provided by the same type flower of different plant and the pin flower. The distyly of L. pinciana born not only morphological but also functional sense.
View
Physiological and Psychological Response to Floral Scent
Article
  • Jan 2013
To better understand how fragrance may enhance human health, this study examined psychophysiological responses to Japanese plum blossom fragrance. Although previous studies used essential oils or fragrance components, the present study measured the effects of floral scent naturally diffused by the plant itself to simulate the way we generally experience natural scent in everyday life. Subjects were Japanese males (n = 26), and the data collected included cerebral and autonomic nervous system activities, semantic differential (SD) scale, and profile of mood states (POMS). Exposure to the fragrance significantly activated the sympathetic nervous system and the cerebral areas related to movement, speech, and memory. SD scale and POMS results showed the fragrance evoked cheerful, exciting, and active images and changed mood states by enhancing vigor while suppressing feelings of depression. These findings indicate that contact with a floral scent such as plum blossom fragrance can improve mood states and may foster the brain functions of memory, speech, and movement, potentially leading to improvements in emotional health, depression, and memory disorders.
View
Design, synthesis, and bioevaluation of paeonol derivatives as potential anti-HBV agents
Article
  • Nov 2014
Hepatitis B virus (HBV) is a causative reagent that frequently causes progressive liver diseases, leading to the development of acute, chronic hepatitis, cirrhosis, and eventually hepatocellular carcinoma (HCC). Despite several antiviral drugs including interferon-α and nucleotide derivatives are approved for clinical treatment for HBV, critical issues remain unresolved, e.g., low-to-moderate efficacy, adverse side effects, and resistant strains. In this study, novel Paeonol-phenylsulfonyl derivatives were synthesized and their antiviral effect against HBV was evaluated. The experimental results indicated that these compounds process significant antiviral potential, including the inhibition of viral antigen expression and secretion, and the suppression of HBV viral DNA replication. Among compounds synthesized in this research, compound 2-acetyl-5-methoxyphenyl 4-methoxybenzenesulfonate (7f) had the most potent inhibitory activity with IC50 value of 0.36 μM, and high selectivity index, SI (TC50/IC50) 47.75; which exhibited an apparent inhibition effect on viral gene expression and viral propagation in cell culture model. So, we believe our compounds could serve as reservoir for antiviral drug development. Copyright © 2014 Elsevier Masson SAS. All rights reserved.
View
Constituents and bacteriostatic activity of volatile matter from four flower plant species
Article
  • Jan 2010
This study was conducted to identify major constituents in the volatile matter from four indoor flowering plants and to evaluate them for bacteriostatic activity of the most abundant compounds. Volatile matter was collected by a dynamic collection method from Gardenia jasminoides, Ceropegia woodii, Pilea nummulariifolli, and Rhoeo purpurea. GC-MS analyses identified that the most abundant terpene compounds were á-pinene and ocimene (14.19% of total volatile matter) in G. jasminoides, á-pinene, camphene, ocimene and eucalyptole (43.91% of total volatile matter) in C. woodii, á-pinene and camphene (45.52% of total volatile matter) in P. nummulariifollia, and á-pinene, camphene and eucalyptole (46.42% of total volatile matter) in R. purpurea. These four terpene monomers have demonstrated strong bacteriostatic activity against six bacterial cultures. The most effective was á-pinene (5μl/ml) which had 100% bacteriostatic rate on all the bacterial cultures. The least effective (34% bacteriostatic rate) was eucalyptole (10μl/ml) against Saprophytic staphylococcus.
View
View