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ChemInform Abstract: Chemical Constituents of Agarwood Originating from the Endemic Genus Aquilaria Plants

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... Agarwood is composed of 52% sesquiterpenes and 41% 2-(2-phenylethyl)-4H-chromen-4one derivatives (Chen et al. 2012a). These two types of chemical compounds are not found in healthy trees of Aquilaria (Tamuli et al. 2005). ...
... The chemical constituents of agarwood originating from Aquilaria, including agarwood essential oil, feature over 150 compounds (Chen et al. 2012a). Agarwood contains many chemical components and they are diverse, complex and most of them are biologically and pharmacologically active, including neural activity, gastrointestinal regulation, antibacterial, antiinflammation, and cytotoxicity (Wang et al. 2018a). ...
... Sesquiterpenes, 2-(2phenylethyl)-4Hchromen-4-one derivatives, aromatics and triterpenes are the main compounds of agarwood (Kalra & Kaushik 2017, Yang et al. 2019) demonstrated the sedation effect of 8 2-(2phenylethyl)-4Hchromen-4-one derivatives extracted from agarwood. Ueda et al. (2006) isolated a sesquiterpene that can be used as a sedative, and similar results were also reported that 2-(2-[phenylethyl)chromone from agarwood have anticancer activity (Chen et al. 2012a, Liu et al. 2016. Chen et al. (2012a) mentioned that sesquiterpenes and 2-(2-phenylethyl)-4Hchromen-4-one derivatives contribute to the characteristics of resin-infiltrated wood. ...
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Agarwood, a precious natural product, can be defined as fragrant dark resinous heartwood of diseased timber of Aquilaria and Gyrinops. Agarwood has been used for thousands of years in several countries as incense, perfumes, and multifunctional pharmaceutical product. The main compounds in agarwood include sesquiterpenes, 2-(2-phenylethyl)-4H-chromen-4-one and its derivatives (PeCs), aromatics, triterpenes and five other categories. Natural agarwood resin production is inefficient and and low yield; thus, it is difficult to meet global demand. Different methods have been implemented to stimulate biological agarwood induction, and the use of endophytic fungi is one of the methods. In this review, we summarize the endophytic fungi and their chemical compounds reported in agarwood.
... It should be noted that many publications have published the species under the synonym Aquilaria agallocha. Major secondary metabolites reported include alkaloids, benzophenones, coumarins, fatty acids, flavonoids, steroids, saponins, tannins, terpenoids, tocopherols, and xanthones (Batubara et al. 2018;Chen et al. 2012;Eissa et al. 2020;Nik Wil et al. 2014;Said et al. 2016). ...
... ,7R,8S)-5,6,7,8-tetrahydro-5,6,7-trihydroxy-4-oxo-2-(2-phenylethyl)-4Hchromen-8-yl]oxy}-4H-chromen-4-one, 7-hydroxy-6-methoxy-2-[2-(4-methoxyphe nyl)ethyl]-4H-1-benzopyran-4-one, 7-(benzyloxy)-5-hydroxy-2-methylchromone, 8,12-epoxyeremophila-9,11(13)-diene, 8βH-dihydrogmelofuran, 9-hydroxyselina-4,11-dien-14-oic acid, 12-deoxy-13-O-acetylphorbol-20-(90Z)-octadecenoate, 12-O-(20E,40E)-6-oxohexa-20,40-dienoylphorbol-13-acetate, 12-O-(20E,40E)-60, 70-(erythro)-dihydroxytetradeca-20,40-dienoylphorbol-13-acetate, 12-O-(20E,40 E)-60,70-(threo)-dihydroxytetradeca-20,40-dienoylphorbol-13-acetate, 24(4R,5R, 7R)-11-hydroxyspirovetiv-1(10)-en-2-one, (2-hydroxyphenyl)ethyl]-4H-chromen-4-one, 5α,6β,7β,8α-tetraacetoxy-5,6,7,8-tetrahydro-2-[2-(4-methoxyphenyl)ethyl)]-4H-chromen-4-one, (2R,3S)-2,3-dimethyl-2-(3-methylbut-2-en-1-yl)-cyclohexanone, (2R,4aS)-1,2,3,4,4a,5,6,7-octahydro-4amethyl-2-(1-methylethenyl)-naphthalene, (3R,5aR,9S,9aS)-Octahydro-2,2,5a-trimethyl-2H-3,9a-methano-1-benzoxepi ne-9-carbaldehyde, (3R,5aS,9aR)-octahydro-2,2,5a-trimethyl-2H-3,9a-methano-1benzoxepine, (3R,5aS,9R,9aR)-octahydro-2,2,5a-trimethyl-2H-3,9a-methano-1-benzoxepin-9-ol, (4aS)-1,2,3,4,4a,5,6,7-octahydro-4a-methyl-2-(1-methylethylidene) naphthalene, (5S,6R,7S,8R,7'R)-hydroxyisoagarotetrol, (5S,6R,7S,8R,7'S)-hydroxyisoagarotetrol, (5R,6R,7S,8R)-5,6,7,8-tetrahydro-5,6,7,8-tetrahydroxy-2-(2-phenylethyl)-4H-chromen-4-one, (5S,6S,7R)-5,6,7-triacetoxy-2-[2-(2-acetoxyphenyl) ethyl]-5,6,7,8-tetrahydro-4H-chromen-4-one, and (8aS)-1,2,3,7,8,8a-hexahydro-8amethyl-6-(1-ethylethyl)naphthalene (Ahmaed and Kulkarni 2017;Chen et al. 2012;Hashim et al. 2014;Hoon 2014;Liu et al. 2018;Ma et al. 2017;Nasution et al. 2019;Senarath et al. 2016;Wagh et al. 2017;Wang et al. 2018;Wu et al. 2012). The shoot also contain cucurbitacin (Chen et al. 2014). ...
... Available reports of bioactivities include the ability to affect the central nervous systems by acting as anesthetic, sedative, and sleep inducer. Other activities including analgesic, antibacterial, anticonvulsant, antidiabetic, antifungal, antihistamine, antinociceptive, antioxidant, antiulcer, antitumor, antimicrobial, anxiolytic, hepatoprotective, and laxative have also been reported (Adam et al. 2017;Alam et al. 2015Alam et al. , 2017Chen et al. 2012;Hashim et al. 2016;Okugawa et al. 1993;Takemoto et al. 2008). Antimicrobial: The roots have antimicrobial properties. ...
... Presently, agarwood and its volatile components are seen as important and efficient natural substances that can be used to produce valuable products such as perfumes and incense because of their fragrance characteristics. Many teams have researched the chemical constituents of agarwood [1,[14][15][16]. ...
... Table 1 shows the representative data. International Journal of Analytical Chemistry 13 14 International Journal of Analytical Chemistry e absorbance at 540 nm was measured after 10 min using an ELISA reader. e amounts of TNFα and IL-1α were calculated from a standard curve created using known concentrations of standards. ...
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Agarwood is generally used to make incense sticks in China and Southeast Asia. It emits smoke with a pleasant odor when burned. There are few reports on the chemical components of smoke generated by burning or heating agarwood. The agarwoods were produced by the whole-tree agarwood-inducing technique (AWIT), agarwood induced by axe wounds (AAW), burning-chisel-drilling agarwood (BCDA), wood of Aquilaria sinensis trees (AS), respectively. Herein, we used GC-MS to analyze the chemical constituents of incense smoke generated from AWIT, AAW, BCDA, AS, and the extracts of sticks from agarwood produced by the whole-tree agarwood-inducing technique (EAWIT), and 484 compounds were identified. A total of 61 chemical constituents were shared among AWIT, AAW, and BCDA. The experimental data showed that aromatic compounds were the main chemical constituents in agarwood smoke and that some chromone derivatives could be cracked into low-molecular-weight aromatic compounds (LACs) at high temperature. Furthermore, agarwood incense smoke showed anti-inflammatory activities by inhibiting lipopolysaccharide- (LPS-) induced TNF-α and IL-1α release in RAW264.7 cells.
... Agarwood, a valuable fragrant natural product, has wide uses in traditional medicine, crafts, and religious ceremonies worldwide (Persoon et al., 2008;Okudera and Ito, 2009;Kakino et al., 2010;Chen et al., 2011Chen et al., , 2012Xu et al., 2013;Rasool and Mohamed, 2016). It is in great demand and has high economic value, making good quality agarwood more expensive than gold in international markets. ...
... Sesquiterpenes are one of the two major components of agarwood (Chen et al., 2011(Chen et al., , 2012. Agarwood sesquiterpenes are not found in healthy tissues, and only accumulate in response to elicitation or wound signals (Brooks et al., 1986;Chappell and Nable, 1987;Yin et al., 1997;Ito et al., 2005;Okudera and Ito, 2009;Kumeta and Ito, 2010;Xu et al., 2013). ...
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Agarwood is derived from wounded Aquilaria trees and is widely used in traditional medicine, incense, and perfume. Sesquiterpenes are one of the main active components in agarwood and are known to be induced by wounding or injury. The molecular mechanism by which wounding leads to sesquiterpene formation remains largely unknown. ASS1 is one of key enzymes responsible for the biosynthesis of sesquiterpenes and is a pivotal jasmonate (JA)-responsive wound-inducible synthase. However, why ASS1 does not express in healthy trees and how its expression is induced as a result of wounding remains unexplored. Here, we report that ASS1 is a wound-induced gene with a promoter in which the 242-bp (-973 to -731bp) region is identified as the core sequence for responding to wound signals. AsWRKY44 binds directly to this region and represses ASS1 promoter activity. Downregulation or disruption of AsWRKY44 can relieve the inhibition and activate ASS1 expression. Further, it is found that in response to the exogenous MeJA, AsWRKY44 is degraded and the expression of ASS1 is significantly upregulated. These findings confirm AsWRKY44 is a crucial negative regulator involved in the regulation of wound-induced ASS1 transcription, which reveals the core mechanism of agarwood sesquiterpenes biosynthesis.
... The main active compounds present in agarwood are terpenoids, specifically sesquiterpenes and derivatives of flindersiachromone (Chen et al. 2012), and the composition of oil extracted from agarwood is exceedingly complex, including over 150 chemical compounds (Naef 2011). As a consequence of the unique fragrant properties of agarwood, it has long been traded as a highly prized cultural, religious, and medical commodity. ...
... Formation of agarwood is usually associated with fungal infection or physical wounding, where resin composed of mixtures of sesquiterpenes and 2-(2phenylethyl)chromones (PECs) are secreted by the tree as a defence mechanism (Naef 2011;Chen et al 2012). Over time, the accumulation of volatile compounds and sesquiterpenoids lead to the formation of fragrant agarwood (Fazila and Halim 2012;Hashim et al 2014). ...
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Trees in the genus Aquilaria (Thymelaeaceae) are known as lign aloes, and are native to the forests of southeast Asia. Lign aloes produce agarwood as an antimicrobial defence. Agarwood has a long history of cultural and medicinal use, and is of considerable commercial value. However, due to habitat destruction and over collection, lign aloes are threatened in the wild. We present a chromosomal-level assembly for Aquilaria sinensis, a lign aloe endemic to China known as the incense tree, based on Illumina short-read, 10X Genomics linked-read, and Hi-C sequencing data. Our 783.8Mbp A. sinensis genome assembly is of high physical contiguity, with a scaffold N50 of 87.6Mbp, and high completeness, with a 95.8% BUSCO score for eudicotyledon genes. We include 17 transcriptomes from various plant tissues, providing a total of 35,965 gene models. We reveal the first complete set of genes involved in sesquiterpenoid production, plant defence, and agarwood production for the genus Aquilaria, including genes involved in the biosynthesis of sesquiterpenoids via the mevalonic acid (MVA), 1-deoxy-D-xylulose-5-phosphate (DXP), and methylerythritol phosphate (MEP) pathways. We perform a detailed repeat content analysis, revealing that transposable elements account for ~61% of the genome, with major contributions from gypsy-like and copia-like LTR retroelements. We also provide a comparative analysis of repeat content across sequenced species in the order Malvales. Our study reveals the first chromosomal-level genome assembly for a tree in the genus Aquilaria and provides an unprecedented opportunity to address a variety of applied, genomic and evolutionary questions in the Thymelaeaceae more widely.
... Hence, it is of great interest to unveil the molecular mechanism to thereby artificially manipulate the process of agarwood formation. It has been demonstrated that the formation of agarwood is characteristically accompanied by the synthesis and accumulation of sesquiterpenoids and 2-(2-phenylethyl)chromones (PECs), which are the principal constituents contributing to the important biological activities and the pleasant fragrance of agarwood [14][15][16][17] . To decipher the molecular mechanism of agarwood formation, great efforts have been made in the past decade to explore the biosynthesis of these two classes of chemicals in agarwood. ...
... PECs are a subgroup of chromones that characteristically bear a phenylethyl group at the C-2 position. Since the first natural PEC, flindersiachromone, was elucidated in 1976 25 , nearly 250 PECs have been isolated exclusively from agarwood [14][15][16][17][26][27][28][29] . In the Chinese pharmacopeia, PECs were legally assigned as diagnostic constituents for evaluating the quality of agarwood. ...
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2-(2-Phenylethyl)chromones (PECs) are the principal constituents contributing to the distinctive fragrance of agarwood. How PECs are biosynthesized is currently unknown. In this work, we describe a diarylpentanoid-producing polyketide synthase (PECPS) identified from Aquilaria sinensis . Through biotransformation experiments using fluorine-labeled substrate, transient expression of PECPS in Nicotiana benthamiana , and knockdown of PECPS expression in A. sinensis calli, we demonstrate that the C 6 –C 5 –C 6 scaffold of diarylpentanoid is the common precursor of PECs, and PECPS plays a crucial role in PECs biosynthesis. Crystal structure (1.98 Å) analyses and site-directed mutagenesis reveal that, due to its small active site cavity (247 Å ³ ), PECPS employs a one-pot formation mechanism including a “diketide-CoA intermediate-released” step for the formation of the C 6 –C 5 –C 6 scaffold. The identification of PECPS, the pivotal enzyme of PECs biosynthesis, provides insight into not only the feasibility of overproduction of pharmaceutically important PECs using metabolic engineering approaches, but also further exploration of how agarwood is formed.
... It is obtained by distillation and is the most principal ingredient for premium perfumes due to its unique fragrance and long-lasting odor. Several studies have been previously conducted to determine AEO qualities (Ismail et al., 2014), to enhance AEO yield by several pretreatments (Yoswathana et al., 2012), and to investigate its phytochemical constituents and their bioactive properties (Abdullah et al., 2007;Ahmaed et al., 2017;Azah et al., 2008;Chen et al., 2012;Dahham et al., 2015;Hashim et al., 2014;Hoque et al., 2018;Ibrahim et al., 2011;Ismail et al., 2014;Radzi et al., 2018;Tajuddin and Yusoff, 2010;Thuy et al., 2019;Wang et al., 2018;Zhang et al., 2014a). On the contrary, there is no record of the study on AEO originating from decaying logs (Gyrinops spp.). ...
... In all AEO assays from different sources, 63 compounds could be identified and 58 of them were found in M1 AEO. All of the detected compounds were commonly found in agarwood from different qualities and sources (Ahmaed and Kulkarni, 2017; Chen et al., 2012;Naef, 2011;Thuy et al., 2019;Wetwitayaklung et al., 2009;Yusoff et al., 2015). ...
... Sukkaew et al. [36] isolated and identified volatile compounds from agarwood by GC-MS. Yang et al. [37] isolated and identified a monoterpene derivative [(-)-bornyl ferulate]. According to the chemical structure, sesquiterpenes isolated from agarwood are divided into different categories including agarofurans, eudesmanes, eremophilanes, guaianes, agarospirols, and cadinanes [38,39]. ...
... Tian and Haigang [45] used petroleum ether and ethanol to extract 10 diterpenoids from agarwood. (-)-bornyl ferulate [37] Steriods Some steroids, such as β-sitosterol and 12 flavonoids, were isolated [48]. ...
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Agarwood is a highly valuable fragrant wood of Aquilaria spp. (Thymelaeaceae) which has been widely utilized in traditional medicine, religious rites, and cultural activities. This study sum-marizes a review on the identification of Aquilaria cultivars, volatile and non-volatile phyto-chemicals, pharmacological uses, and agarwood grading system to determine its quality, and different agarwood induction methods. Due to the highly demanding and depleted natural re-sources, the research on agarwood is still insufficient, and it has broad research and develop-ment prospects in many industries. However, due to the significant scientific nature of agar-wood application, developing high-quality products and drugs from agarwood have become highly important, while no one has discussed in detail the phytochemicals uses and provided a summary until now. The main phytochemicals of agarwood include terpenoids, dominated by sesquiterpenes. For centuries, terpenoids have been used in traditional Chinese medicine and have been shown to possess various pharmacological properties, including bacteriostatic, anti-bacterial, sedation, analgesia, anti-inflammation, anti-asthmatic, hypoglycemic, antidepressant, and many others. Alongside biological activity screening, phytochemical advances and phar-macological research have also made certain progress. Therefore, this review discusses the re-search progress of agarwood in recent years and provides a reference basis for further study of Aquilaria plants and agarwood.
... The agarwood is known with different names in different parts of the world such as Aloe wood in Indonesia, Malaysia, and Papua New Guinea as Gaharu, in Japan as Jin-koh, in China as Chen Hsiang or Chen Xiang, in Korea as Chim-Hyuang and Oud or and so on [1]. Agarwood is a resinous part of Aquilaria tree which is formed in response to biotic and abiotic stress [2]. ...
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Aims: The study was accomplished for assessing the impact of agar oil production on livelihood improvement of its producers. Study Design: This article is a socioeconomic study and placed on empirical analysis. It conducted the socioeconomic factors which had an impact on the livelihood improvement of agar oil producers. Place and Duration of Study: The study was conducted at Barlekha Upazilla of Maulvibazar District of Bangladesh. The study period was mid-June to mid-September/2017. Methodology: The relevant data were collected from the agar oil producers of Maulvibazar District, Bangladesh. Household having at least one factory were included for the study. A total of 60 households among 180 household were selected as sample. Field survey data were collected through face to face interviewing of the respondents using a structured questionnaire through simple random sampling. After cleaning and correcting the data Microsoft Excel and Statistical Package for Social Science (SPSS) were used for analyzing the data. Results: The average family size was found 10.17 (small: 10%; medium: 45% and large: 45%) and majority (63.3%) belongs to the graduation level, meaning having 16.0 years of education. The results of the regression model revealed that amount of annual income, credit access of household, membership of an organization had the positive impact and an increasing the age of household head had a negative effect on livelihood improvement. Instead of having different constraints, the major problems faced by the producers in agar oil production were lack of industrial gas connection and lack of modern laboratory. Conclusion: In order to enrich the livelihood improvement of agar oil producer’s industrial gas connection, modern laboratory and better credit services should be well executed by different government and non-government organization.
... The main compounds in agarwood are sesquiterpenes and chromone derivatives [2,[9][10]; their compositions in natural and arti cial agarwood are greatly different. Many studies have been conducted to discriminate between the qualities of natural and arti cial agarwood. ...
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Background: Agarwood is widely used as a traditional medicine all over the world. Distinction between the qualities of natural and artificial agarwood is a current hot research topic among agarwood research communities. An important sensory characteristic of agarwood lies in its incense smoke, and an analysis of incense smoke has been traditionally used to evaluate the agarwood quality since ancient times. The aim of this study is to establish a rapid detection method using electronic nose (E-nose) systems to distinguish between natural and artificial agarwood. Result: Incense smokes of 45 natural and artificial agarwood samples were analyzed by E-nose, and principal component analysis (PCA) was employed to cluster the E-nose data. The chemical markers which could be used to distinguish between artificial and natural agarwood were identified by GC-MS combined with information value and decision tree algorithm. The results showed that the smellprints of artificial agarwood contained more peaks, while those of natural agarwood had higher response intensities. The compounds that were different between the two types of agarwood were three sesquiterpenes and six chromone derivatives. The result from decision tree algorithm further showed that 6-hydroxy-2-(2-phenylethyl)chromone was the chemical marker that could be used to distinguish between artificial and natural agarwood. Nootkatone and 2-(2-phenylethyl)chromone were the chemical markers that may contributed to the clustering of the E-nose data; the two compounds can be used to evaluate the incense smoke of agarwood. Conclusion: We demonstrated that our developed E-nose-based method could rapidly distinguish between the incense smokes of artificial and natural agarwood; this method could be applied to evaluate the quality of agarwood in the future.
... It has been reported that the primary chemical constituents of agarwood are sesquiterpenes and 2-(2-phenylethyl)chromones, which account for 52% and 41%, respectively. 9 2-(2-Phenylethyl)chromones are a class of uncommon chromone compounds, of which the highly oxidised 5,6,7,8-tetrahydro-2-(2-phenylethyl)chromones are unique components found in agarwood so far. 1,10,11 Lancaster and Espinoza reported the application of the highly oxidised 5,6,7,8-tetrahydro-2-(2-phenylethyl)chromones for identification of agarwood and for verifying compliance of commercial products. ...
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Introduction Agarwood is a highly valuable fragrant resinous wood which is widely used as traditional Chinese medicines, perfumes, incense and decorations. Due to its high economic value and excessive demand, this leads to a rising price and proliferation of fake commodities. Thus, strict authenticity identification and quality evaluation of agarwood are of great significance. Objective To establish a simple, rapid and non‐destructive technique for identifying the authenticity of agarwood. Methods Liquid extraction surface analysis mass spectrometry (LESA‐MS) was firstly proposed to identify the authenticity of 62 agarwood samples without sample preparation. In addition, multivariate statistical models and thin‐layer chromatography (TLC) method were used to analyse and verify the results of LESA‐MS. Results Representative compounds of agarwood were detected by LESA‐MS. A characteristic 2‐(2‐phenylethyl)chromone compound (m/z 319.1) was treated as a key chemical marker to identify agarwood and its counterfeits rapidly. Several other chromones ions were identified and used as additional evidence for authentic samples. A total of 62 samples were visually discriminated as two groups by principal component analysis (PCA) and orthogonal projection to latent structures discriminant analysis (OPLS‐DA), and the specific characteristic marker was highlighted. Moreover, the qualitative results of the conventional TLC method were in agreement with the LESA‐MS approach. Conclusion The proposed LESA‐MS method was successfully applied in the direct qualitative analysis of agarwood from different sources. This study indicated great feasibility and practicality of LESA‐MS in the rapid identification of agarwood, and provided a non‐destructive and meaningful preliminary screening tool for the agarwood industry.
... Agarwood is resinous wood obtained from wounded Aquilaria tree, which is a genus belonging taxonomically to the ymelaeaceae family [1]. e main constituents in agarwood are volatile constituents and semi-volatile components [2]. ...
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Wild Chi-Nan agarwood is regarded as the highest quality agarwood from Aquilaria spp. However, the comprehensive research on chemical composition of wild Chi-Nan agarwood is limited. An integrated strategy using SHS-GC-MS and UPLC-Q/Tof-MS was applied to explore the phytochemical characteristics of a kind of agarwood induced from a newly identified germplasm of Chi-Nan A. sinensis. Progenesis QI and MS-Dial were used to preprocess the UPLC-Q/Tof-MS and GC-MS raw data, respectively. Principle component analysis (PCA) and orthogonal partial least squares to latent structure-discriminant analysis (OPLS-DA) models were built to discriminate Chi-Nan agarwood from ordinary agarwood and to screen potential distinguishing components between them. In this study, we clarified the distinguishing differences between Chi-Nan agarwood and ordinary agarwood. The difference is mainly manifested in the average contents of 2-(2-phenylethyl)chromone and 2-[2-(4′-methoxybenzene)ethyl]chromone, which are 170 and 420 times higher in Chi-Nan agarwood than in ordinary agarwood, respectively, while the contents of 5,6,7,8-diepoxy-2-(2-phenylethyl)chromones(DEPECs), 5,6-epoxy-2-(2-phenylethyl)chromones(EPECs), and 5,6,7,8-tetrahydro-2-(2-phenylethyl)chromones(THPECs) such as agarotetrol are extremely low. The content of the main sesquiterpenes in Chi-Nan agarwood was higher than that in ordinary agarwood, especially in regard to guaiane and eudesmane derivatives. In addition, there were significant differences in the contents of low-molecular-weight aromatic compounds such as 2-methyl-4H-1-benzopyran-4-one, 4-methoxybenzaldehyde, and 2-hydroxybenzaldehyde between Chi-Nan agarwood and ordinary agarwood. All the mentioned main chemical characteristics of this new Chi-Nan agarwood were coincident with those of the rare wild Chi-Nan agarwood from A. malaccensis, A. sinensis, and A. crassna. We reported differences in 2-(2-phenylethyl)chromones, sesquiterpenes, and low-molecular-weight aromatic compounds between Chi-Nan agarwood and ordinary agarwood from A. sinensis for the first time; it is necessary to evaluate the agarwood from the new-found Chi-Nan germplasm. 1. Introduction Agarwood is resinous wood obtained from wounded Aquilaria tree, which is a genus belonging taxonomically to the Thymelaeaceae family [1]. The main constituents in agarwood are volatile constituents and semi-volatile components [2]. The former include low-molecular-weight aromatic compounds and sesquiterpene derivatives, and the latter principally consist of 2-(2-phenylethyl)chromone derivatives [3]. Sesquiterpenes, including agarofurans, cadinanes, eudesmanes, eremophilanes, guaianes, and agarospiranes, are considered to be the prominent contributors to agarwood aroma [4]. 2-(2-phenylethyl)chromone monomers can be divided into four categories based on the A ring of 2-(2-phenylethyl)chromones, namely, 5,6,7,8-tetrahydro-2-(2-phenylethyl)chromones (THPECs), diepoxy-tetrahydro-2-(2-phenylethyl)chromones (DEPECs), epoxy-tetrahydro-2-(2-phenylethyl)chromones (EPECs), and flindersia type 2-(2-phenethyl)chromones (FTPECs) [2, 5]. Chi-Nan agarwood (CNA), a high-quality agarwood, is also called Qi-Nan or Jar-Nan in China, Kanankoh or Kyara in Japan, and Tagara in India [6]. In China, wild CNA is considered representative of high-quality agarwood, whose price is increasing up to thousands of RMB yuan per gram [7, 8]. Wild Chi-Nan agarwood is valued for its mysterious and elegant oriental odour that could be obviously smelt without heating, which make it discriminate from other kinds of agarwood. Investigations on wild CNA have rarely been reported, in contrast to abundant reports related to ordinary agarwood. In 1985, Hashimoto proved that benzaldehyde and 4-methoxybenzaldehyde originated from the pyrolysis of 2-(2-phenylethyl)chromone and 2-[2-(4′-methoxyphenyl)ethyl]chromone, respectively, in the neutral part of Kyara [9]. Ishihara discovered that the relative contents of 2-(2-phenylethyl)chromone and 2-[2-(4′-methoxyphenyl)ethyl]chromone from Kanankoh (A.agallocha, synonym: A. malaccensis) [10] smoke were much higher than those from Jinkoh [11]. In addition, taking four types of wild CNA (A. sinensis and A. agallocha) as materials, Dai showed that there were abundant 2-(2-phenylethyl)chromones and 2-[2-(4′-methoxyphenyl)ethyl]chromones [6, 12]. It is not difficult to notice that previous studies took only the 2-(2-phenylethyl)chromones into account. In addition, Chinese pharmacologist Xie Zongwan described the morphological characteristics of CNA but failed to provide information on the original plant [13]. Due to the confusion regarding the original plant, relevant information on wild CNA has seldom been described in the mentioned studies. In recent years, a kind of special agarwood germplasm of A. sinensis has been introduced and domesticated from the wild population and propagated by grafting with ordinary germplasm of A. sinensis. Agarwood with more than 40% of the alcohol soluble extractive content can be obtained after this kind of tree is wounded with the drilling method over one year. However, for ordinary germplasm of A. sinensis, it is almost impossible to obtain agarwood with more than 10% of the alcohol soluble extractive content with the same inducing method [14]. Because of the similarity of characteristics such as appearance, form, texture, color, smell, and taste to wild CNA, this new-found agarwood is also called CNA. To date, there has been only one report by Li [15]in which the chemical properties of this kind of CNA have been tested by TG-FTIR and HS-GC-MS, and these authors named it Kynam. However, the authors did not clarify the specific components to distinguish CNA in terms of fragrance and the chemical characteristics of CNA. Here, gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-mass spectrometry (LC-MS) were used to analyze the differences between CNA induced from new-found germplasm and ordinary agarwood (OA) to obtain a deep knowledge of phytochemical characteristics. 2. Materials and Methods 2.1. Agarwood Materials Thirteen agarwood samples were analyzed as shown in Table 1 and Figure S1. They are divided into CNA (Chi-Nan agarwood) and OA (ordinary agarwood) group. The seven CNA samples were collected from new-introduced germplasms A. sinensis tree that were provided by three farmers from different planting bases of Hainan and Guangdong province in China. As for the OA group, we chose six ordinary agarwood induced with three kinds of common agarwood-inducing methods, including whole-tree agarwood-inducing technique (Agar-Wit) [16], burning-chisel-drilling (BCD), and wild. Num. Species Agarwood induction method Place of production Description Sinkage CNA1 A. sinensis 3-year-old Chi-Nan germplasm by drilling for 15 months Ding’an, Hainan province Irregular pieces, black brown resin bands alternate with yellow white wood stripes, sufficient resin, rich of aromas, acrid in taste, soft and glutinous x CNA2 A. sinensis 3-year-old Chi-Nan germplasm by drilling for 14 months Ding’an, Hainan province Irregular strips, brown resin bands and white wood are distributed alternately, strong fragrance, cool feeling, bitter in taste, hard texture, slightly sticky x CNA3 A. sinensis 5-year-old Chi-Nan germplasm by drilling for 18 months Ding’an, Hainan province Irregular pieces, black brown resin scatter like spots, adequate resin, the aroma is thick, numb the tongue, hard texture, sticky √ CNA4 A. sinensis 10-year-old Chi-Nan germplasm by drilling for 12 months Maoming, Guangdong province Irregular strips, apparent brown resin spread throughout the surface, intense aroma, taste peppery, hard texture, sticky √ CNA5 A. sinensis 3-year-old Chi-Nan germplasm by drilling for 12 months Maoming, Guangdong province Irregular pieces, black brown resin scatter like spots, saturated with resin, fragrance is elegant, spicy and numb, tough, sticky x CNA6 A. sinensis 20-year-old Chi-Nan germplasm by drilling for 18 months Maoming, Guangdong province Irregular pieces, black brown resin scatter like spots or stripe, quite strong aroma, little spicy and numb, tough, sticky √ CNA7 A. sinensis 3-year-old Chi-Nan germplasm by drilling for 12 months Maoming, Guangdong province Irregular pieces, obvious black brown resin scatter like spots or stripe, cool feeling, taste peppery and numb, tough, soft and glutinous √ OA1 A. sinensis 6-year-old trees induced by Agar-Wita for 18 months Haikou, Hainan province Irregular slices, brown resin bands alternate with yellow white wood stripe, pleasant fragrance, crisp x OA2 A. sinensis 6-year-old trees induced by Agar-Wit for 8 months Danzhou, Hainan province Irregular thin slices, saturated with resin brown resin, sweet fragrance, crisp x OA3 A. sinensis Wild agarwood Hainan province Irregular pieces, massive protrusions and patches distribute throughout the appearance, slight aroma, soft x OA4 A. sinensis Wild agarwood Hainan province Irregular pieces, many protrusions and patches distribute throughout the appearance, tawny resin scatter like spots, slight aroma, crisp x OA5 A. sinensis 5-year-old trees induced by BCDb for 12 months Maoming, Guangdong province Irregular pieces or slices, tawny resin and white wood are distributed alternately, many fibers in the cross section, slight aroma, resilient x OA6 A. sinensis 5-year-old trees induced by BCD for about 12 months Maoming, Guangdong province Irregular pieces, brown resin scatter like spots, cheerful, aroma, crisp x aThe abbreviation of whole-tree agarwood-inducing technique is Agar-Wit. bThe abbreviation of burning-chisel-drilling is BCD. “√”: the agarwood sample could sink in water. “x”: the agarwood sample could not sink in water.
... The localized of resin accumulation due to the continuously induction mechanism caused by the slow release system (Fig. 5). Agarwood oil is a complex mixture of aromatic terpene compounds included monoterpenes, sesquiterpenes and diterpenes (Naef, 2011;Chen et al., 2012). The main compounds present in agarwood oil have been identified as the sesquiterpenes. ...
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Agarwood is a type of resin impregnated wood produced from the wounded Aquilaria trees. This agarwood gives a pleasant fragrant when it is burned. It becomes high-priced and increase demanded in the world due to the depletion of wild agarwood in the forest caused by illegal poaching activities. Agarwood resin can only be produced by injuring caused by lightning or wounded by animals under natural conditions. However, the natural process of resin accumulation is uncertain and time-consuming. Therefore, we developed an agarwood inducement technique that served as the alternative way to induce the agarwood formation in a short time. Three inducement techniques, including the injecting method, knocking method and combination of injecting & knocking method were applied to induce resin formation. In this study, we evaluated the technique for producing agarwood in species Aquilaria beccariana, which is native and only can be found in Borneo Malaysia. For A. beccariana trees treated with the inducement technique, resin formed and spread throughout the cell in the trunk. The evaluation results showed that the agarwood yield per tree reached around 5 to 7 kilogram. Furthermore, this agarwood derived from the induction was found to have a similar quality with the wild agarwood. This indicates the inducement technology had successfully produced agarwood resin in A. beccariana with a grade similar to the wild agarwood.
... Agarwood is a famous traditional Chinese medicine that has been used for more than a thousand years for the treatment of various diseases; especially in the treatment of gastrointestinal diseases have better curative effect [2,3]. It has been shown that sesquiterpenes and 2-(2-phenylethyl)chromone derivatives are two predominant constituents of agarwood [4,5]. Our previous study showed that the components of WTAAE included sesquiterpenes (10.615%), chromone (31.678%), aromatics (31.831%), and other known compounds (25.760%) and also showed that sesquiterpenes and chromone are two predominant constituents of agarwood [6]. ...
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Background: Agarwood has been used for centuries, especially for treatment of gastrointestinal diseases. Earlier studies of our laboratory suggested that agarwood alcohol extracts (AAEs) provided gastric mucosal protection. This study aims to investigate the ameliorative effect of AAEs on ethanol-induced gastric ulcers and its mechanism. Methods: Mice were given agarwood induced by the whole-tree agarwood-inducing technique alcohol extract (WTAAE, 0.71, 1.42, and 2.84 g/kg), wild agarwood induced by axe wounds alcohol extract (WAAE, 2.84 g/kg), and burning-chisel-drilling agarwood alcohol extract (FBAAE, 2.84 g/kg) orally, respectively. After 7 days' pretreatment with AAEs, the gastric ulcers were induced by absolute ethanol. The ulcer index, gastric histopathology, biochemical parameters, and inflammatory proteins were evaluated. Results: Pharmacological results showed AAEs (1.42 and 2.84 g/kg) reduced the gastric occurrence and ulcer inhibition rates up to more than 60%. AAEs decreased the level of nitric oxide (NO) and increased glutathione (GSH) and superoxide dismutase (SOD) levels. Besides, AAEs decreased the levels of interleukin-1β (IL-1β) and interleukin-6 (IL-6), but the interleukin-10 (IL-10) was upregulated. The expressions of nuclear factor kappa B (NF-κB) and phosphorylated protein 38 (p-P38) were inhibited. The effect of WTAAE was better than that of FBAAE and similar to that of WAAE at the dose of 2.84 g/kg. Conclusions: These results demonstrate that agarwood alleviates the occurrence and development of gastric ulcers via inhibiting oxidation and inflammation.
... The agarwood and its application has a wide history especially in medicinal manufacture, as an incense, and in perfumery elements [2]. Other than that, the agarwood oil also used as a symbol of wealth especially in the Middle East Countries, and being burnt during religious as well as wedding ceremony [2][3][4][5]. ...
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span>This paper presents the analysis of agarwood oil compounds quality classification by tuning quadratic kernel parameter in Support Vector Machine (SVM). The experimental work involved of agarwood oil samples from low and high qualities. The input is abundances (%) of the agarwood oil compounds and the output is the quality of the oil either high or low. The input and output data were processed by following tasks; i) data processing which covers normalization, randomization and data splitting into two parts in which training and testing database (ratio of 80%:20%), and ii) data analysis which covers SVM development by tuning quadratic kernel parameter. The training dataset was used to be train the SVM model and the testing dataset was used to test the developed SVM model. All the analytical works are performed via MATLAB software version R2013a. The result showed that, quadratic tuned kernel parameter in SVM model was successful since it passed all the performance criteria’s in which accuracy, precision, confusion matrix, sensitivity and specificity. The finding obtained in this paper is vital to the agarwood oil and its research area especially to the agarwood oil compounds classification system.</span
... The last two genera, namely Aquilaria and Gyrinops, which belong to the same family Thymelaeaceae, are very common genus known as agarwood plant producer. A dark resin and aromatic wood of agarwood is caused by its response to various forms of injury, including natural injuries, such as lightning strikes, animal grazing, insect attacks or microbial invasions, or artificial injuries, such as cutting, nailing, binding, fire, chemical wounds, and intentional fungal inoculation [1] [2]. ...
Article
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Gyrinops versteegii is an endemic plant in Lombok, West Nusa Tenggara, which produce agarwood. In vitro anti-oxidant and anti-diabetes activities from several extracts of agarwood produced by G. versteegii were investigated. The 1, 1-diphenyl-2-picrylhydrazyl (DPPH)-radical scavenging activity assay was used to determine the anti-oxidant activity, whereas the α-glucosidase inhibitory activity assay was conducted to determine the anti-diabetes activity. The toxicity test using brine shrimp lethality test (BSLT) and phytochemical analysis were also conducted in this experiment. As the results, the acetone extracts of infected wood of G. versteegii had the highest anti-oxidant activity with the IC50 value of 65.62 μg/mL, whereas the acetone extracts of agarwood had the α-glucosidase inhibitory activity with the IC50 value of 53.46 μg/mL. The toxicity test to the both samples shows the high toxicity with the LC50 values of 1.98 and 15.44 μg/mL, respectively. The high anti-oxidant and anti-diabetes activities in both of the acetone extracts of infected wood and agarwood may be caused by their high content of total phenolic (12.75 and 9.17%, respectively) and total flavonoid (19.96 and 14.34%, respectively). The anti-diabetes activity found in agarwood extracts produced by G. versteegii from Lombok is firstly reported.
... Results of the analysis on chemical composition are presented in Table 1. Chemical composition of agarwood extracts was characterized by mainly the compounds of sesquiterpene group and of chromone derivative group [5,14]. The presence of sesquiterpene compounds as contained in agarwood resins could bring about their sweet-smelling smell aroma. ...
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This research aimed to study about chemical composition and anti-cancer activities of natural agarwood and cultivated agarwood ( Gyrinops vertegii [Gilg.] Domke). Agarwood used in the research was of lowest qualities, which comprised agarwood with natural kemedangan type (A), with cultivated kemedangan-I type (B1), and with cultivated kemedangan-II type (B2), all after methanol extraction. Chemical composition was examined using GC-MS instrument, meanwhile tests on lungs associated anticancer activities (A549’s cancer cells) were performed using MTT method. Chemical composition in low-quality agarwoods was predominantly sesquiterpene compounds, comprising among others guaiacol, cumene, aromadendrene, aplha-humulene, velleral, etc; and conservely did not contain chromone derivative compounds which are compounds characterizing quality agarwood. Low-quality agarwood extracts afforded efficacious potency as anticancer actions against A549’s lungs-attacking cancer cells with IC 50 values at 144.92 µgmL ⁻¹ (A); IC 50 at 206.88 µgmL ⁻¹ (B1), and IC 50 187.97 µgmL ⁻¹ (B2).
... A number of previous studies reported that 2-(2-phenylethyl) chromones and derivates are key components in agarwood formation and quality [29,[40][41][42][43]. For a practical genetic improvement, it has been shown that 2-(2-phenylethyl) chromones and derivates were the key biomarkers for agarwood formation in A. sinensis [8]. ...
Article
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Background Agarwood is a highly sought-after resinous wood for uses in medicine, incense, and perfume production. To overcome challenges associated with agarwood production in Aquilaria sinensis , several artificial agarwood-induction treatments have been developed. However, the effects of these techniques on the metabolome of the treated wood samples are unknown. Therefore, the present study was conducted to evaluate the effects of four treatments: fire drill treatment (F), fire drill + brine treatment (FS), cold drill treatment (D) and cold drill + brine treatment (DS)) on ethanol-extracted oil content and metabolome profiles of treated wood samples from A. sinensis . Results The ethanol-extracted oil content obtained from the four treatments differed significantly (F < D < DS < FS). A total of 712 metabolites composed mostly of alkaloids, amino acids and derivatives, flavonoids, lipids, phenolic acids, organic acids, nucleotides and derivatives, and terpenoids were detected. In pairwise comparisons, 302, 155, 271 and 363 differentially accumulated metabolites (DAM) were detected in F_vs_FS, D_vs_DS, F_vs_D and FS_vs_DS, respectively. The DAMs were enriched in flavonoid/flavone and flavonol biosynthesis, sesquiterpenoid and triterpenoid biosynthesis. Generally, addition of brine to either fire or cold drill treatments reduced the abundance of most of the metabolites. Conclusion The results from this study offer valuable insights into synthetically-induced agarwood production in A. sinensis .
... Analysis of extracted agarwood oil has revealed that it is a complex mixture of sesquiterpenes and its derivatives, derivatives of chromones, sesquiterpenic alcohols, oxidized derivatives, agarospirol, jinkohol-eremol, jinkohol and kesenol of which a few gives the distinctive fragrance to agarwood (Ishihara et al. 1993). Besides, sesquiterpenes and phenylethyl chromones are the key aromatic components in agarwood (Chen et al. 2012;Ishihara et al. 1993;Naef 2011;Yagura et al. 2003). Sesqiterpenes are known to play an important role as defensive agents against many insects in conifers in nature as enumerated by Okudera and Ito (2009), and have also been reported to play decisive role in vitro conditions as shown in callus suspension cultures of A. malaccensis by Jayaraman and Mohamed (2014) when challenged with fungal extract. ...
Article
Aquilaria malaccensis produces exorbitant aromatic wood known as agarwood. The fragrant wood is primarily utilized for its aroma as a retainer of perfume and medicinal values, making it a high-value product suitably called liquid gold. Only infected trees produce agarwood which are exploited for agarwood oil extraction resulting in indiscriminate cutting of trees and its inclusion in Appendix II of the CITES. The current research aims to understand the changes in gene expression during agarwood deposition in A. malaccensis under natural condition. Expression of 25 genes involved in terpenoids biosynthesis was assessed by semi-quantitative PCR followed by qRT-PCR using RNA obtained from infected and non-infected wood. Seven housekeeping genes were also screened of which, GAPDH served as the best potential internal reference gene. Our results showed that, nine of 25 primer pairs tested can differentiate gene expression of agarwood and healthy wood. The genes involved in sesquiterpenoid biosynthesis pathway were up regulated up to 41.59 fold in agarwood as compared to healthy wood which suggests the involvement of these genes in agarwood formation. Sesquiterpene biosynthesis genes were found to be express more in naturally infected Aquilaria plants as compared to artificially induced plants.
... Agarwood is a resinous material mainly produced from heartwood of various Aquilaria and Gyrinops species of the family Thymelaeaceae. 1,2 It is distributed in the areas ranging from India eastwards throughout Southeast Asia, as well as in southern China including Guangdong, Guangxi, Hainan and Fujian. 3 Interestingly, agarwood is hardly formed in the normal tree, while infected by fungi or naturally wounded such as wind, lightning strikes and the gnawing of ants to the tree may stimulate the accumulation of resin. ...
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Background: Agarwood, as a traditional Chinese medicine, has great potential value for the treatment of tranquilization. However, its potential mechanisms and biomarkers are still unclear. Methods: In this study, ultra-high performance liquid chromatography-quadrupole-Exactive Orbitrap mass spectrometry (UHPLC-Q-Exactive Orbitrap-MS)-based metabonomics was adopted to discover the potential biomarkers in mice after agarwood incense smoke (AIS) intervention. Furthermore, the chemical components in agarwood were identified based on UHPLC-Q-Exactive Orbitrap-MS. The global view of potential compound-target-pathway (C-T-B) network was constructed through network pharmacology to understand the potentially material basis of biomarkers. Results: Metabolic profiling indicated that the metabolic changed significantly in mice serum after AIS intervention. A total of 18 potential biomarkers closely related to insomnia and emotional disease were identified, mainly involving in tryptophan metabolism, arginine and proline metabolism, cysteine and methionine metabolism and steroid hormone biosynthesis pathways. A total of 138 components in agarwood were identified based on UHPLC-Q-Exactive Orbitrap-MS. The results showed that mainly compounds such as flidersia type 2-(2-phenylethyl) chromones (FTPECs) and sesquiterpenes exerted good docking abilities with key target proteins, which were involved in multiple diseases including depression and hypnosis. Conclusion: In conclusion, this study enhanced current understanding of the change of metabolic markers after AIS intervention. Meanwhile, it also confirmed the feasibility of combining metabolomics and network pharmacology to identify active components and elucidate the material basis of biomarkers and mechanisms.
... and Gyrinops reported that only 7-10% of tree contains agarwood, which sesquiterpenes and 2-(2-phenylethyl)-4H-chromen-4-one was the major chemical constituent (Naef, 2011;Chen et al., 2012). Although terpenoids have been found in the host plant (agarwood) as well as on the potential endophytic fungi in this study, the relationship between them are still unclear; whether it is mutualistic, symbiotic, antagonistic, or slightly pathogenic. ...
... Agarwood is a highly valuable, fragrant, and dark resinous heartwood of trees in the family Thymelaeaceae [1][2][3][4]. Agarwood is also known under different names in different regions, including agar (Hindi), akil (Tamil), aloe wood (Indonesian), chen xiang (Chinese), chim-hyuang (Korean), eaglewood (Papua New Guinea), gaharu (Malaysian), jin-koh (Japanese), mai ketsana (Lao), mai kritsana (Thai), oud (Arabic), oud or agar attar (Middle Eastern), sasi or sashi (Assamese), and tramhuong (Vietnamese) [5][6][7]. The plants in the family Thymelaeaceae, especially the genera Aquilaria and Gyrinops, are well known for agarwood production, and these are grown in several countries in Southeast Asia (e.g., Borneo, Cambodia, China, India, Indonesia, Laos, Malaysia, New Guinea, Thailand, Philippines, and Vietnam) [2,3,8,9]. ...
Article
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Agarwood is a fragrant dark resin produced in plants belonging to the family Thyme-laeaceae and which has a high economic value. The unique fragrance and medicinal applications intensify the value of agarwood. The wild populations of agarwood trees are highly threatened by high economic demand. Therefore, it is worthwhile to develop an artificial agarwood induction technology for the countries that rely on agarwood from the natural habitat of the plants. Fungal induction of agarwood has been shown to be an efficient method. Interestingly, most of the fungi known from agarwood are endophytic. In this paper, we supplement and update the bioactivity of fungi associated with agarwood and their ability to induce agarwood formation. According to the existing literature, 59 endophytic fungal strains of 16 genera induce agarwood production, most of which belong to Fusarium (28 identified strains). Hence, Fusarium is a good candidate for further studies on fungal induced agarwood production.
... Because natural bioactive compounds have many benefits in medicine and health, the extraction process will be optimized to obtain these beneficial bioactive compounds. A previous study reported that agarwood contains extensive aromatic compounds, mainly sesquiterpenes and phenylethyl chromone derivatives (Chen et al., 2012). These compounds are indicators to determine the quality of the agarwood, particularly resulting from synthetic inoculation process. ...
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The method of extraction of Agarwood is usually dependent on the purpose of the extract. This systematic review aims to look at the number of studies that use different types of solvents in the process of extraction. There are 3 types of solvents commonly used in the extraction of agarwood essential oils namely methanol, ethanol and water. Each solvent produces different extracts in terms of quantity and quality of the final product. However, there is controversy over the use of solvents as it may cause a cytotoxic effect on the user. Another common type of solvent is water. Although water is a cheap solvent and relatively safe, aqueous extracts have more impurities that make isolating the desired compound difficult. After the extraction process, the crude extract was fractionated into the desired compounds and this technique is widely applied, especially in the whole process of extraction of the agarwood. In conclusion, extraction solvents have certain advantages and disadvantages, and this is one of the reasons why this extraction method depends on the purpose of using the final product such as agarwood essential oil.
... These studies came out with a huge number of compounds many of which have proven multiple types of actions on live cells as well as on laboratory animals. The two major components found in agarwood-producing trees are sesquiterpenes and chromones among others such as aromatics, phenols, and triterpenes [98]. ...
Article
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The inflammatory response is a central aspect of the human immune system that acts as a defense mechanism to protect the body against infections and injuries. A dysregulated inflammatory response is a major health concern, as it can disrupt homeostasis and lead to a plethora of chronic inflammatory conditions. These chronic inflammatory diseases are one of the major causes of morbidity and mortality worldwide and the need for them to be managed in the long term has become a crucial task to alleviate symptoms and improve patients’ overall quality of life. Although various synthetic anti-inflammatory agents have been developed to date, these medications are associated with several adverse effects that have led to poor therapeutic outcomes. The hunt for novel alternatives to modulate underlying chronic inflammatory processes has unveiled nature to be a plentiful source. One such example is agarwood, which is a valuable resinous wood from the trees of Aquilaria spp. Agarwood has been widely utilized for medicinal purposes since ancient times due to its ability to relieve pain, asthmatic symptoms, and arrest vomiting. In terms of inflammation, the major constituent of agarwood, agarwood oil, has been shown to possess multiple bioactive compounds that can regulate molecular mechanisms of chronic inflammation, thereby producing a multitude of pharmacological functions for treating various inflammatory disorders. As such, agarwood oil presents great potential to be developed as a novel anti-inflammatory therapeutic to overcome the drawbacks of existing therapies and improve treatment outcomes. In this review, we have summarized the current literature on agarwood and its bioactive components and have highlighted the potential roles of agarwood oil in treating various chronic inflammatory diseases.
... Because natural bioactive compounds have many benefits in medicine and health, the extraction process will be optimized to obtain these beneficial bioactive compounds. A previous study reported that agarwood contains extensive aromatic compounds, mainly sesquiterpenes and phenylethyl chromone derivatives (Chen et al., 2012). These compounds are indicators to determine the quality of the agarwood, particularly resulting from synthetic inoculation process. ...
Article
Full-text available
The method of extraction of Agarwood is usually dependent on the purpose of the extract. This systematic review aims to look at the number of studies that use different types of solvents in the process of extraction. There are 3 types of solvents commonly used in the extraction of agarwood essential oils namely methanol, ethanol and water. Each solvent produces different extracts in terms of quantity and quality of the final product. However, there is controversy over the use of solvents as it may cause a cytotoxic effect on the user. Another common type of solvent is water. Although water is a cheap solvent and relatively safe, aqueous extracts have more impurities that make isolating the desired compound difficult. After the extraction process, the crude extract was fractionated into the desired compounds and this technique is widely applied, especially in the whole process of extraction of the agarwood. In conclusion, extraction solvents have certain advantages and disadvantages, and this is one of the reasons why this extraction method depends on the purpose of using the final product such as agarwood essential oil.
Article
Agarwood is a resinous wood of Aquilaria species and has been used for various applications. Burning agarwood incense is a common practice in temples and homes in Asia. Kynam is widely regarded as high-quality agarwood in the market. Recently, cultivated grafting Kynam (CGK) has emerged as a new agarwood product in the market, which greatly affects the price of high grading Kynam agarwood. In this study, the morphology, ethanol extract content, and incense chemical profile of CGK was investigated and compared with those of wild Kynam (WK) and cultivated common agarwood (CCA). The incense smoke of CGK was analyzed by thermogravimetric Fourier transform infrared spectroscopy (TG-FTIR) and headspace gas chromatography-mass spectrometry (HS-GC-MS). The results showed that the heating of most incenses occurred below 200 °C, and the mass-loss rate value of CGK was between those of WK and CCA. The HS-GC-MS analysis showed the chemical compounds of incense smoke of CGK at 40, 100, and 180 °C, corresponding to the head, middle, and tail of the heating process, respectively. The results suggested that the sesquiterpenes compounds were the major contributors to the mysterious and elegant odoriferous character of agarwood incense. However, a peak area percentage analysis revealed a significant difference in the predominant compounds between CGK and WK, especially at lower temperatures. Therefore, it is not straightforward to substitute WK with CGK. The results are helpful for the study and usage of the new cultivated grafting Kynam agarwood and the development of the agarwood incense industry.
Article
Six new dimeric 2-(2-phenylethyl)chromones (1–6) were isolated from the EtOAc extract of artificial agarwood originating from Aquilaria sinensis (Lour.) Glig. Their structures were unambiguously elucidated by spectroscopic techniques (UV, IR, 1D and 2D NMR), and HRESIMS analysis, as well as by comparison with the literature. The absolute configurations were determined by ECD spectra.
Article
Three new dimeric 2-(2-phenylethyl)chromones crassin I ∼ K (1–3), together with one known analogue (4), were isolated from the artificial holing agarwood originating from Aquilaria sinensis. Their structures including the absolute configuration were elucidated by spectroscopic techniques (UV, IR, 1D and 2D NMR, ECD), and HRESIMS analysis, as well as by comparison with the literature data. Compounds 1 and 2 exhibited weak acetylcholinesterase inhibitory activity.
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Trees in the genus Aquilaria (Thymelaeaceae) are known as lign aloes, and are native to the forests of southeast Asia. Lign aloes produce agarwood as an antimicrobial defence. Agarwood has a long history of cultural and medicinal use, and is of considerable commercial value. However, due to habitat destruction and over collection, lign aloes are threatened in the wild. We present a chromosomal‐level assembly for Aquilaria sinensis, a lign aloe endemic to China known as the incense tree, based on Illumina short‐read, 10X Genomics linked‐read, and Hi‐C sequencing data. Our 783.8Mbp A. sinensis genome assembly is of high physical contiguity, with a scaffold N50 of 87.6Mbp, and high completeness, with a 95.8% BUSCO score for eudicotyledon genes. We include 17 transcriptomes from various plant tissues, providing a total of 35,965 gene models. We reveal the first complete set of genes involved in sesquiterpenoid production, plant defence, and agarwood production for the genus Aquilaria, including genes involved in the biosynthesis of sesquiterpenoids via the mevalonic acid (MVA), 1‐deoxy‐D‐xylulose‐5‐phosphate (DXP), and methylerythritol phosphate (MEP) pathways. We perform a detailed repeat content analysis, revealing that transposable elements account for ~61% of the genome, with major contributions from gypsy‐like and copia‐like LTR retroelements. We also provide a comparative analysis of repeat content across sequenced species in the order Malvales. Our study reveals the first chromosomal‐level genome assembly for a tree in the genus Aquilaria and provides an unprecedented opportunity to address a variety of applied, genomic and evolutionary questions in the Thymelaeaceae more widely.
Conference Paper
Aquilaria crassna is an Asian traditional plant with diverse Pharmaceutical and industrial properties. Different extraction methods affect the yield and functional activities of the plant products. The current study was designed to measure the performances of five extraction methods (supercritical-fluid extraction SFE, hydrodistillation, steamdistillation, n-hexane and ethanol) on agarwood samples. The stem bark extracts were subjected for anti-proliferative effect using common cancer cell lines (colorectal, pancreatic, prostate and breast). In addition, the scavenging activity was evaluated using two methods (diphenylpicrylhydrazyl) (DPPH) and ferric reducing antioxidant power (FRAP). The present of essential oils was detected by transmission electron microscopy (TEM). The hydrodistillation and (SFE) extracts provided the highest yield with significant antioxidant and anticancer results.
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Agarwood study is getting importance day today because of its advancement in chemical benefits as well as benefits in healthcare. This study elaborates and reviews the detailed structure of agarwood with its benefits in medicine as well as our life. The agarwood has a high density and can sink in water. The aromatic components contained in it can emit fragrance. Agarwood has a magnificent, rare and durable gemstone character. Like ordinary organic gemstones, it is a collection of organic, inorganic and trace elements formed by animal and plant life activities. Long related resin line texture. The agarwood has a fine particle size, compact structure, low hardness, rich color, and luster. It is important to understand the benefits from the Agarwood with its chemical composition in order to get benefits that are cost-effective as well as health benefits.
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Three new 5,6,7,8-tetrahydro-2-(2-phenylethyl)chromones and one new dimeric 2-(2-phenylethyl)chromone were isolated from the agarwood of Aquilaria crassna Pierre ex Lecomte in Laos. The structures of the isolates were elucidated by spectroscopic methods, and their configurations were determined via ROESY correlations, ³JH-H coupling constants analyses, comparisons of chemical shifts and specific rotations with known compounds, and ECD calculation in the case of 1. Compounds 1–4 were evaluated for their cytotoxicity. Compounds 1 and 2 exhibited weak cytotoxicity toward HeLa cell line (IC50: 49.8 ± 1.2 μM) and K562 cell line (IC50: 42.66 ± 0.47 μM), respectively.
Article
Covering: Up to the end of 2019. Agarwood is a resinous portion of Aquilaria trees, which is formed in response to environmental stress factors such as physical injury or microbial attack. It is very sought-after among the natural incenses, as well as for its medicinal properties in traditional Chinese and Ayurvedic medicine. Interestingly, the chemical constituents of agarwood and healthy Aquilaria trees are quite different. Sesquiterpenes and 2-(2-phenethyl)chromones with diverse scaffolds commonly accumulate in agarwood. Similar structures have rarely been reported from the original trees that mainly contain flavonoids, benzophenones, xanthones, lignans, simple phenolic compounds, megastigmanes, diterpenoids, triterpenoids, steroids, alkaloids, etc. This review summarizes the chemical constituents and biological activities both in agarwood and Aquilaria trees, and their biosynthesis is discussed in order to give a comprehensive overview of the research progress on agarwood.
Article
Agarwood is a well-known and precious traditional Chinese medicine, has been widely applied as drugs and spices for century. The large demand for this material has deeply stimulated the emergence of numerous cultivated products. However, it is difficult to distinguish wild agarwood from cultivated agarwood, and the chemical composition difference between them is not clear. In this study, an integrated method of Fourier transform near-infrared (FT-NIR), gas chromatography-mass spectrometry (GC-MS) and ultraperformance liquid chromatography Quadrupole-Exactive Orbitrap tandem mass spectrometry (UHPLC-Q-Exactive Orbitrap/MS) was developed to explore chemical variation between wild and cultivated agarwood in combination with multivariate statistical analysis. Twenty-four wild and cultivated agarwood samples were collected from different regions. FT-NIR profiles were used to obtain the holistic metabolic characterization in combination with principal component analysis (PCA). A total of seventy-six and seventy-nine metabolites, including volatile components and 2-(2-phenethyl) chromones derivatives, were successfully identified by GC-MS and UHPLC-Q-Exactive Orbitrap/MS, respectively. Thereafter, the orthogonal-partial least square method-discriminant analysis (OPLS-DA) and variable importance in the projection (VIP) were used to screen potential characteristic chemical components (VIP>1) in wild and cultivated agarwood, respectively. Finally, eight key chemical markers were putatively identified by two techniques to distinguish agarwood from different origins, which can be found that sesquiterpenes, aromatics, terpenoids, 2-(2-phenylethyl) chromones of the flidersia type (FTPECs) and tetrahydro-2-(2-phenylethyl) chromones (THPECs) are the most important metabolites. Summary, this research presented a comprehensive metabolomic variation between wild and cultivated agarwood on the basis of a multi-technology platform, which laid a foundation for distinguishing the two ecotypes of agarwood and was conducive to the quality control of this resource.
Article
Aquilaria sinensis is a species of plant endemic to China, which is typical wound-induced economic plant. It is widely used in the production of perfume, incense and traditional Chinese medicine. A healthy A. sinensis tree cannot produce agarwood. It forms agarwood only when wounded. Sesquiterpenes and phenylethyl chromone derivatives have been demonstrated to be the main active compounds in agarwood, but little is known about jasmonate (JA) signaling that regulates the biosynthesis of agarwood sesquiterpenes. In this work, we firstly cloned the full-length cDNA sequence of a JA signaling suppressor gene (JAZ) from A. sinensis, and then characterized its roles through bioinformatics prediction, tissue expression, wounding-induced expression, subcellular localization, protein interaction and overexpression analysis in Arabidopsis thaliana. The results showed that the full-length cDNA sequence of JAZ gene (termed as AsJAZ1, GenBank accession number: KP677281) is 1507 bp, containing a complete open reading frame (ORF) of 990 bp. The bioinformatics analysis shows that the deduced amino acid residues contain a tify (ZIM) domain, the same as A. thaliana JAZ3 protein. Mechanical wounding and MeJA were found to up-regulate the expression level of the AsJAZ1 gene. The AsJAZ1 could interact with the MYC2 transcription factor in vitro. The MYC2 transcription factor in Arabidopsis thaliana (AtMYC2) was minimally expressed in transgenic plants and had a weak response to MeJA treatment. The AsJAZ1 overexpression in A. thaliana was observed to down-regulate the expression of sesquiterpene synthase genes (TPS21 and TPS11), suggesting that AsJAZ1 might serve as a repressor to regulate the expression of sesquiterpene synthase genes in Aquilaria plants. Taken together, this work may lay a foundation for identifying the JA signaling pathway and exploring the role of JA signaling in agarwood sesquiterpene biosynthesis in A. sinensis trees.
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The phytochemistry of the fragrant infected heartwood of Aquilaria and Gyrinops species, agarwood (oud), is critically reviewed, highlighting the use of this remarkable natural raw material in perfumery. The chemistry of the two main groups of constituents of agarwood (sesquiterpenoids and chromones) is discussed, focusing particularly on the former structural type. The identities of the main key odorants of agarwood essential oil and of the smoke produced by heating the wood of agarwood are also discussed.
Article
Aquilaria crassna Pierre ex Lecomte, Thymelaeaceae, is cultivated for producing resinous heartwood, also called agarwood. Its leaves are a source of herbal tea in Vietnam due to its rich content of polyphenols. However, the α-glucosidase inhibition activity and the contents of phenolic compounds in leaves of different ages have not yet been determined. In the current study, 7 polyphenols [iriflophenone 3,5-C- β-D-diglucoside (1), iriflophenone 3-C- β-D-glucoside (2), mangiferin (3), iriflophenone 2- O- α-rhamnoside (4), genkwanin 5- O- β-primeveroside (5), genkwanin 4′-methyl ether 5- O- β-primeveroside (6), and genkwanin (7)] were isolated from the leaves of A crassna. Among them, genkwanin (7), an O-methylated flavone, was the most active compound that inhibited α-glucosidase activity, with an IC 50 value of 24.0 μM. Molecular docking studies were performed to understand the binding interactions of the active compounds. In addition, a reliable and straightforward reversed-phase HPLC method was developed to determine the content of compounds in different leaves of A crassna. Mangiferin (3) showed the highest content. The contents of 1-4 contributed to the total polyphenolic contents and significantly decreased from the youngest to the oldest leaf. The contents of 5-7 fluctuated through various ages of leaves. Compounds 5 and 6 showed a low accumulation in the first and second leaves, then obtained high contents among middle leaves and declined in the oldest. These results suggested that A crassna and its polyphenols may prevent the development and progression of diabetes through α-glucosidase inhibition. Also, the analysis of the polyphenol content in A crassna may be helpful for tea product manufacture.
Article
Spiroaquilarenes A–E (1–5), a class of sesquiterpene polymers featuring unusual furaneol rings connecting sesquiterpene units, were isolated from agarwood of Aquilaria sinensis and structurally characterized.
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Aquilaria sinensis (Lour.) Gilg is the resin-containing wood of the Aquilaria. Agarwood is a traditional Chinese medicine included in the 2020 edition of Chinese Pharmacopoeia. The main phytochemicals of agarwood include terpenoids, dominated by sesquiterpenes. For centuries, terpenoids have been used in traditional Chinese medicine and have been shown to possess various pharmacological properties, including bacteriostatic, antibacterial, sedation, analgesia, anti-inflammation, anti-asthmatic, hypoglycemic, antidepressant, and many others. Alongside biological activity screening, phytochemical advances and pharmacological research have also made certain progress.
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Aquilaria sinensis)为对象,基于高通量测序方法,分析 2 个不同区域生境中 4 个品种白木香结香部位真菌群落结构多样性及分布规律,结合不同品种的结香特性,进一步挖掘 与白木香结香显著相关的真菌类群,促进结香技术的提升。结果表明:相同生境条件下,同种白木香不同高度结香位 点真菌组成结构非常相似,但不同真菌的丰度存在差异;不同区域生境下,相同品种结香部位真菌群落组成结构存在 显著差异,生境差异可能是导致结香部位真菌群落结构差异的主要因素之一;同一区域生境下,不同品种白木香结香 部位的真菌群落结构存在显著差异,品种差异可能是导致白木香结香部位真菌群落结构差异的主要因素之一,同时特 有真菌类群的存在也可能是影响白木香结香特性的关键。Fusarium spp. 和 Hypomontagnella spp. 等真菌在易结香品种 分布广泛且丰度极高,可能与易结香品种的结香特性相关,具有重要的应用潜力。 关键词:白木香;结香技术;真菌多样性;高通量测序 中图分类号:S567.1 文献标识码:A Abstract: Aquilaria sinensis (Lour.) Spreng, an economic plant in Guangdong, was selected as the object of this study. Using the high-throughput sequencing method, we analyzed the community structure and distribution of fungi in agar-wood wound locations of four agarwood varieties in Maoming and Dongguan, China. Combining the agarwood formation characteristics of different varieties, fungal groups were further investigated which were significantly related to the agarwood formation. Under the same habitat condition, fungi community structure at different height sampling sites in the same varieties were remarkably similar, despite the different fungi abundance. The fungal community composition were significantly different in the same varieties under different habitats, and the difference of habitat may be one of the main factors leading to the difference of fungal community structure. There were significant differences in the fungal community structure among different varieties under the same habitat condition. Different agarwood varieties may be one of the main factors leading to the difference of fungal community structure. The unique fungi with high abundance maybe result in special feature of agarwood formation. Fusarium spp. and Hypomontagnella spp., which are widely distributed with high abundance in the easy agarwood formation varieties, are the best illustrations for this conclusion.
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Agarwood has high economic value and wide uses, however, the amount of wild agarwood is scarce. Wild agarwood with high oil content may contain strains associated with agarwood production. To improve the formation of agarwood, we produced fungal inducers from a high-oil wild agarwood block containing enrichment fungi. We investigated the composition of strains and inoculated the fungal inducers into Aquilaria trees. We analyzed the content of alcohol-soluble extract, essential oil, agarotetraol, 2-(2-phenylethyl)chromone, 6,7-dimethoxy-2-(2-phenylethyl)chromone and total chromone, and the chemical components of alcohol-soluble extract. We aimed to assess agarwood quality through these evaluations. The results demonstrated that fungi extracted from wild agarwood with high oil content can effectively improve the yield and quality of agarwood, and Gongronella butleri, Saitozyma podzolica, Cladorrhinum bulbillosum, Humicola grisea and Tetracladium marchalianum were the species found novel as inoculant for agarwood formation. After 12 months of inoculation, agarwood produced using A. sinensis had higher quality, the contents of alcohol-soluble extract, essential oil, total chromones, and the total relative contents of sesquiterpenes and chromones were 21.73 % ±2.97 %, 6.07 % ±0.47 %, 12.30 % ±2.21 %, and 97.59 %, respectively. Over 6–18 months of inoculation, agarotetrol content decreased, and 2-(2-phenylethyl) chromone and 6,7-dimethoxy-2-(2-phenylethyl)chromone content first increased and then decreased.
Article
One new 2-(2-phenylethyl)chromone (1), three new naturally occurring 2-(2-phenylethenyl)chromones (3–5), together with a known 2-(2-phenylethyl)chromone (2) were isolated from the EtOH extract of agarwood originating from Aquilaria crassna in Cambodia. Their structures were unambiguously elucidated by detailed spectroscopic (NMR, UV, IR, MS) analyses. All the compounds were tested for acetylcholinesterase (AChE) inhibitory activity and cytotoxicity against tumor cell lines (K562, BEL-7402, SGC-7901 and Hela). Compound 1 displayed weak AChE inhibitory activity (inhibitory ratio: 35.0 ± 2.19%) and cytotoxicity against K562 tumor cell line (IC50: 40.81 ± 0.64 μM). Along with, compound 3 showed cytotoxicity against BEL-7402 tumor cell line (IC50: 44.18 ± 0.34 μM).
Article
Eleven previously unreported sesquiterpenes, including nine eudesmane-type (agalleudesmanol A-I) and two agarospirane-type sesquiterpenes (agarospiranic aldehyde A-B), together with eight known sesquiterpenes, were isolated from the agarwood of Aquilaria agallocha Roxb. The structures were established based on extensive spectroscopic analyses, including infrared (IR), high-resolution electrospray ionisation mass spectrometry (HRESIMS), nuclear magnetic resonance (NMR), X-ray diffraction, quantum chemical calculations based on empirical electronic circular dichroism (ECD) data, and DP4+ probability analysis. The bioactivity of these undescribed compounds against lipopolysaccharide (LPS)-induced NO production in RAW 264.7 cells was evaluated. Compounds 1 and 2 exhibited significant anti-inflammatory activities, with IC50 values of 5.46–14.07 μM (aminoguanidine as positive control, IC50 20.33 ± 1.08 μM).
Article
Agarwood, one of the precious woods in the globe, is produced by Aquilaria plant species during an upshot of wounding and infection. Produced as a defence response, the dark, fragrant resin gets secreted in the plant's duramen, which is impregnated with fragrant molecules with the due course. Agarwood has gained worldwide popularity due to its high aromatic oil, fragrance, and pharmaceutical value, which makes it highly solicited by numerous industries. Predominant chemical constituents of agarwood, sesquiterpenoids, and 2-(2-phenylethyl) chromones have been scrutinized to comprehend the scientific nature of the fragrant wood and develop novel products. However, the genes involved in the biosynthesis of these aromatic compounds are still not comprehensively studied in Aquilaria. In this study, publicly available genomic and transcriptomics data of Aquilaria agallochum were integrated to identify putative functional terpene synthase genes (TPSs). The in silico study enabled us to identify ninety-six TPSs, of which thirty-nine full-length genes were systematically classified into TPS-a, TPS-b, TPS-c, TPS-e, TPS-f, and TPS-g subfamilies based on their gene structure, conserve motif, and phylogenetic comparison with TPSs from other plant species. Analysis of the cis-regulatory elements present upstream of AaTPSs revealed their association with hormone, stress and light responses. In silico expression studies detected their up-regulation in stress induced tissue. This study provides a basic understanding of terpene synthase gene repertoire in Aquilaria agallochum and unlatches opportunities for the biochemical characterization and biotechnological exploration of these genes. Supplementary information: The online version contains supplementary material available at 10.1007/s12298-021-01040-z.
Article
Significance Incense has been linked to ceremonies, religions, medicines, and cosmetics worldwide for thousands of years. While Chinese texts in the Tang dynasty (618 to 907 CE) indicate that numerous exotic aromatic substances were already being introduced into China through the land and maritime Silk Road, this has been rarely demonstrated archaeologically. This study identifies three types of incense associated with the sacred sarira of Sakyamuni Budda from the underground palace of Famen Royal Temple in central China, providing direct evidence of aromatics including elemi, agarwood, and frankincense as well as their composite product, namely Hexiang (blending of aromatics), in Buddhist activities, which may have promoted the spread of incense and the development of aromatic knowledge systems in medieval China.
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Agarwood is resinous valuable heartwood of Aquilaria tree resulting from self–defence mechanism towards injuries or damages exerted on the tree. Agarwood essential oil is usually extracted through a process of hydrodistillation or steam distillation which is beneficial for commercial purposes such as perfumeries and cosmetics. Hydrosol, a byproduct of the process produced in abundance and underutilized particularly in the agarwood industry. Hydrosol of agarwood is an aromatic compound that is believed to have chemical properties similar to essential oils that consist of positive antioxidant activity and positive biological activity for living cells. Several studies on properties of hydrosol of agarwood show that it contained zero nutrient but varied with minerals in the appropriate proportion that safe for human consumption. Thus, this review was aimed to discuss the agarwood hydrosol processing methods, characteristics, antioxidants properties and its comparisons to other plants hydrosol that have been commercially used as human consumption as in flavoured and non-flavoured beverages
Article
Ethnopharmacological relevance Stress is a state of feeling that inhibits one from responding properly in the face of a threat. Agarwood smoke has been used in traditional medicine as a sedative anti-anxious, and anti-restless therapy. Its scent emitted from heat induces people to enter a stable state; however, the underlying molecular effect is still unclear. Aim of the study This study analyzed novel biological events and gene expression signatures induced by agarwood incense smoke in mice. Materials and Methods Incense smoke was produced by heating at 150 ºC for 30 min in a headspace autosampler oven. We treated mice with exposure to incense smoke from Kynam agarwood for 45 min/day for 7 consecutive days. After a 7-day inhalation period, the potent agarwood smoke affected-indicators in serum were measured, and the RNA profiles of the mouse brains were analyzed by microarray to elucidate the biological events induced by agarwood incense smoke. Results Chemical profile analysis showed that the major component in the incense smoke of Kynam was 2-(2-phenylethyl) chromone (26.82%). Incense smoke from Kynam induced mice to enter a stable state and increased the levels of serotonin in sera. The emotion-related pathways, including dopaminergic synapse, serotonergic synapse, GABAergic synapse, long-term depression and neuroactive ligand-receptor interaction, were significantly affected by incense smoke. Moreover, the expression of Crhr2 and Chrnd genes, involved with neuroactive ligand-receptor interaction pathway, was upregulated by incense smoke. Conclusions By a newly-established incense smoke exposure system, we first identified that anti-anxious and anti-depressant effects of agarwood incense smoke were likely associated with the increase of serotonin levels and multiple neuroactive pathways in mice.
Article
Callus browning, a common feature in plant cell cultures, has hardly been explored in Aquilaria sinensis. Here, the volatile organic compounds (VOCs) were characterized during the browning of A. sinensis cells using Gas Chromatography-Mass Spectrometry (GC–MS), and total sesquiterpene accumulation was significantly induced and peaked during A. sinensis callus browning, after 60 days of callus growth. Additionally, 14 types of sesquiterpenes were detected in the browning A. sinensis callus, with greater sesquiterpene diversity than in the ones treated with methyl jasmonate and salicylic acid (SA) in a previous study. To further evaluate the mechanism of regulation of agarwood sesquiterpenes during cell browning in A. sinensis, changes on phytohormone concentrations were explored using ultra-performance liquid chromatography-electrospray tandem mass spectrometry system (UPLC-ESI-MS/MS). Both endogenous jasmonic acid and SA, key plant defense hormones, increased during A. sinensis callus browning. 1-aminocyclopropanecarboxylic acid, an ethylene (ET) precursor, decreased significantly after A. sinensis callus browning. Conversely, two primary growth hormones, auxin and cytokinin, exhibited opposite trends, suggesting that they also play roles in agarwood sesquiterpene accumulation. Our results potentially offer novel insights that could facilitate the production valuable phytochemical compounds such as agarwood sesquiterpenes, using plant cell cultures treated with appropriate phytohormone combinations.
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To analyze the constituents of essential oil from Chinese eaglewood [resinous wood of Aquilaria sinensis (Lour.) Gilg] and its anti-methicillin-resistant Staphylococcus aureus (MRSA) activity. The essential oil was extracted by water-steam distillation and analyzed by GC/MS method. The relative contents of the compounds were determined by normalization. The compounds were characterized by NIST05 and WILEY275L database matching and comparison of their MS spectra with those of literature data. Antibacterial activity of the oil was assayed by the filter paper disc agar diffusion method. The oil showed sig-nificant antibacterial activity against MRSA. Sixty-six chromatographic peaks were detected, among them thirty compounds com-prising 59.80% of the total essential oil were characterized. Twenty-six compounds comprising 54.26% of the oil were identified as sesquiterpenes. β-Agarofuran (8.96%), kusunol (7.82%), (-)-jinkoh-eremol (5.04%), agarospirol (4.53%), baimuxifuranic acid (4.09%) were the major sesquiterpenes. Four nor-sesquiterpenes and some other sesquiterpenes, such as 10-epi-γ-eudesmol, α-agarofuran, epi-ligulyl oxide, etc. were detected in Chinese eaglewood oil for the first time. This is the first report about anti-MRSA activity of Chinese eaglewood oil from A. sinensis. there are few studies on the Chinese eaglewood oil from A. sinensis. In our recent research on the oils of five different kinds of Chinese eaglewood, several sesquiterpenes, such as hinesol, nootkatone, valerenic acid, velleral, viridiflorol, etc., were found to be present in the oils by GC/MS analysis for the first time [4] . The present paper describes the GC/MS analysis and anti-methicillin-resistant Staphylococcus aureus (MRSA) results of a new sample of Chinese eaglewood oil, in which some sesquiterpenes, especially four nor-sesquiterpenes were characterized for the first time. 2. Experimental 2.1. Sample preparation Naturally produced Chinese eaglewood from the tree of A. sinensis was collected in Tunchang county of Hainan Province of China in February 2007. The plant was identified by associate Professor Zheng-Fu Dai and a voucher specimen (No. 070286) is deposited at the Institute of Tropical Bioscience and Biotechnology. Hydrodistillation of 260 g of the milled Chinese eagle-wood was carried out using a Clevenger-type appa-ratus for 4 h. After drying with anhydrous sodium sulfate, 0.55 mL pale yellow oil with pleasant odour was obtained and the yield was 0.21% (v/w).
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Aquilaria agallocha Roxb, family Th ymelaeaceae, is an evergreen plant of India, China and Tibet, commonly described as aloe wood or agar wood. Traditionally, bark, root and heartwood are used for their medicinal properties as a folk medicine to treat infl ammation, arthritis, vomiting, cardiac disorders, cough, asthma, leprosy, anorexia, headache and gout. Th e present study was carried out to investigate the antioxidant activity of ethyl acetate extract of Aquilaria agallocha (EAA). EAA was tested in vitro at diff erent concentrations for inhibitory eff ect on nitrite-induced oxidation of haemoglobin in human blood hemolysate. Results indicate a strong antioxidant eff ect of EAA in a concentration range of 500-3500 μg/ml. However, pro-oxidant activity was observed at higher concentrations of these compounds. Key words: Aquilaria agallocha, antioxidant, nitrite-radical, methemoglobin
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The resinous portions of Aquilaria plants, called agarwood, have been used as medicines and incenses. Agarwood contains a great variety of sesquiterpenes, and a study using cultured cells of Aquilaria showed the production of sesquiterpenes (α-guaiene, α-humulene, and δ-guaiene) to be induced by treatment with methyl jasmonate (MJ). In this study, the accumulation and production of sesquiterpenes were quantified. The amounts accumulated and produced reached a maximum at 12 h, and the most abundant product was α-humulene at 6 h and δ-guaiene after 12 h. However, a headspace analysis of the cells revealed that α-humulene is likely to be volatilized; so overall, the most abundant sesquiterpene in the cells was δ-guaiene. A cDNA library from RNA isolated from MJ-treated cells was screened using PCR methodologies to isolate five clones with very similar amino acid sequences. These clones were expressed in Escherichia coli, and enzymatic reactions using farnesyl pyrophosphate revealed that three of the clones yielded the same compounds as extracted from MJ-treated cells, the major product being δ-guaiene. These genes and their encoded enzymes are the first sesquiterpene synthases yielding guaiane-type sesquiterpenes as their major products to be reported. Expression of a fourth terpene synthase gene in bacteria resulted in the accumulation of the protein in insoluble forms. Site-directed mutagenesis of the inactive clone and three-dimensional homology modeling suggested that the structure of the N-terminal domain was important in facilitating proper folding of the protein to form a catalytically active structure.
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Two new 2-(2-phenylethyl)chromones, (5S(*),6R(*),7S(*))-5,6,7-trihydroxy-2-(3-hydroxy-4-methoxyphenethyl)-5,6,7,8-tetrahydro-4H-chromen-4-one (1) and (5S(*),6R(*),7R(*))-5,6,7-trihydroxy-2-(3-hydroxy-4-methoxyphenethyl)-5,6,7,8-tetrahydro-4H-chromen-4-one (2), were isolated from the Chinese eaglewood of Aquilaria sinensis (Lour.) Gilg. Their structures were established by detailed MS and NMR spectroscopic analysis, as well as comparison with the literature data.
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A new 2-(2-phenylethyl)chromone, 5,6,7,8-tetrahydroxy-2-(3-hydroxy-4-methoxyphenethyl)-5,6,7,8-tetrahydro-4H-chromen-4-one (1) was isolated from the Chinese eaglewood [Aquilaria sinensis (Lour.) Gilg]. Its structure was established by detailed MS and NMR spectroscopic analysis, as well as comparison with literature data.
Article
Objective: To study the chemical constituents of Aquilaria sinensis. Methods: Column chromatographic technique was employed for the isolation and purification of its constituents by solvent, the ether fraction of ethanol extract of A. sinensis was conducted gradient elution by petroleum ether and ethyl acetate in different proportions. Their structures were identified by physicochemical constant and spectral analysis (IR, UV, EI-MS, 1H-NMR, 13C-NMR, and HMBC). Results: The compounds were identified from their ethanol extracts as: 6, 8-dihydroxy-2-[2-(3′-methoxy-4′-hydroxyl phenylethyl)] chromone (I) and 6-methoxy-2-[2-(3′-methoxy- 4′-hydroxyl phenylethyl)] chromone (II). Conclusion: Compound I is a novel compound and II is a known one.
Article
New tetraphydroxy-2-(2-phenylethyl)chromone, tentatively named AH16 was isolated from agalwood, "Jinko", and the structure was characterized as (5R__-, 6R__-, 7S__-, 8R__-)-2-(2-phenylethyl)-5e', 6a, 7e, 8e'-tetraphydroxy-5, 6, 7, 8-tetraphydrochromone, assuming the cyclohexenyl ring to have a boat conformation.
Article
New dioxan-linked bi-2-(2-phenylethyl)chromone, tentatively named AH21 was isolated from a pridine extract of agalwood "Jinko" and structurally characterized using proton and carbon-13 nuclear magnetic resonance spectra.
Article
Calli and suspension cell culture were established from Aquilaria species whose resinous portion was called agarwood and used as medicine and incense. Four different strains of calli were analyzed for fragrant compounds such as sesquiterpenoids and chromone derivatives which were the major components of agarwood. Main sesquiterpenoids detected from calli were α-guaiene, α-humulene and δ-guaiene, and those of chromone derivatives were phenylethylchromones (AH3, AH4, AH5, AH6). Amount of these compounds differed among the four strains, indicating that Aquilaria plants may have variation in capacity for fragrant compound production. Incubation temperature analysis was also done from 20°C to 40°C and resulted that cell growth was the best at 25°C, whereas the amount of fragrant compounds was largest at 20°C. Salicylic acid (SA) and methyl jasmonate (MJ) were added to calli and suspension cell culture respectively in order to induce production of fragrant compounds. Both SA and MJ apparently induced production of three sesquiterpenoids, α-guaiene, α-humulene, and δ-guaiene at early stage of treatment of SA or MJ, but did not induce that of chromone derivatives directly. Further studies of time course of chromone production and cell viability suggested that cell death may take part in chromone production, and that phenylethylchromones would be produced via oxydoagarochromones (OACs). These results indicate that sesquiterpenoids are synthesized in living cells, but chromone derivatives may be produced from debris of dying cells. © 2009 The Japanese Society for Plant Cell and Molecular Biology.
Article
Two new phenylethylchromone derivatives were isolated from a methanol soluble portion of pyridine extract of agalwood (Jinko). Their structures were elucidated as (5S, 6R, 7S, 8R, 7'R)-7'-hydroxyisoagarotetrol (1) and its (7'S)-isomer (2), respcetively.
Article
Three new bi-2-(2-phenylethyl)chromones, tentatively named AH12, AH13and AH14, were isolated from agalwood "Jinko" along with AH10, AH11 and AH15. The structures of AH12 and AH13 were elucidated as (5S, 6R, 7R, 8S)-2-(2-phenyletyl)-5, 6, 7-trihydroxy-5, 6, 7, 8-tetrahydro-8-[2-(2-phenylethyl)-7-methoxychromonyl-6-oxy]chromone and its de-7-methoxylate, respectively. AH14 was concluded to be (5S, 6S, 7S, 8R)-2-(2-phenylethyl)-6, 7, 8-trihydroxy-5, 6, 7, 8-tetrahydro-5-[2-(2-phenylethyl)chromonyl-6-oxy]chromone. Elucidation of 5, 6' and 8, 6'-ether bonding in bi-2-(2-phenylethyl)chromones was done by detailed analyses of the proton and carbon-13 nuclear magnetic resonance (1H and 13C-NMR) spectra, and measuring nuclear Overhauser effect (NOE) difference values.
Article
Six kinds of chromone derivatives, named AH1, AH2, AH3, AH4, AH5 and AH6, were isolated from agarwood (Jinko) from Kalimantan. Four constituents, AH3, AH4, AH6 and AH5, were characterized as 6-hydroxy-(I), 6-methoxy-(II) and 6, 7-dimethoxy-2-(2-phenylethyl) chromone (IV) and 6-methoxy-2-[2-(3-methoxyphenyl) ethyl] chromone (III), respectively.
Article
Three new kinds of phenylethylchromone derivatives, called AH17 AH20 and AH23, were isolated from acetone and pyridine extracts of agalwood (Jinko) from Kalimantan. The structures of AH17 and AH23 were characterized as 5α, 6β, 7β-trihydroxy-8α-methoxy-2-(2-phenylethyl-5, 6, 7, 8-tetrahydrochromone and 5α, 6β, 7β, 8α-tetrahydroxy-2-[2-(2-hydroxyphenyl)ethyl]5, 6, 7, 8-tetrahydrochromone, respectively. AH20 was found to be a trimer formed by the ether-linkage made of 2-(2-phenylethyl)chromone and 2mol of agarotetrol at C5, 8' and C6, 5'.
Article
New bi- and tri-2- (2-phenylethyl) chromones, tentatively named AH15 and AH18 were isolated from Agalwood “Jinko” and their structures were determined.
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A new chromone, 2-(2-4'-methoxyphenylethyl)chromone (I) was isolated together with 2-(2-phenylethyl)chromone (II: flidersiachromone) from agarwood (Japanese name; JINKOH). On pyrolysis at 150°C. I and II were found to produce 4-methoxybenzaldehyde and benzaldehyde, respectively. It is considered that these chromones, which are odorless at room temperature, contribute to the pleasant, lasting odor obtained when agarwood is burnt as an incense. © 1985, The Pharmaceutical Society of Japan. All rights reserved.
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New bi-2-(2-phenylethyl) chromones, tentatively named AH10 and AH11 were isolated from Agalwood "Jinko" and their structures were determined.
Article
The structures of two compounds, AH1 and AH2, isolated from agalwood "Jinko" were studied. AH1 was obtained as needles having a melting point different from that of agarotetrol (powder) isolated and characterized by Yoshii et al. However, the carbon-13 nuclear magnetic resonance (13C-NMR) data and [α]D values of the two compounds were identical, and AH1 was concluded to have the same structure, including stereochemistry, as agarotetrol. The half-chair conformation of the hexenyl ring moiety assumed by Yoshii et al. was confirmed by detailed analyses of the proton nuclear magnetic resonance (1H-NMR) and 2D-COSY spectra.AH2 was assigned the structure (5S, 6R, 7R, 8S)-2-(2-phenylethyl)-5e', 6e, 7e, 8'e-tetrahydroxy-5, 6, 7, 8-tetrahydrochromone, a stereo-isomer of agarotetrol (7S, 8R), on the basis of the 1H-NMR, X-ray analysis and circular dichroism (CD) spectral data. It was named isoagarotetrol. The hexenyl ring moiety of isoagarotetrol was found to have a half-chair conformation identical to that of agarotetrol in the crystalline state as well as in solution.
Article
Three new phenylethylchromone derivatives, tentatively named AH7, AH8 and AH9, were isolated from acetone and pyridine extracts of agalwood (jinko) from Kalimantan. AH7 from the pyridine extract was characterized as 5, 8-dihydroxy-2-(2-phenylethyl)chromone, and AH8 from the acetone extract was elucidated to be 6, 7-dimethoxy-2-[2-(4-methoxyphenyl)chromone. AH9, acetylated in order to separate it from the mixture, was concluded to be (5S, 6S, 7R)-5a', 6a, 7a-triacetoxy-2-[2-(2-acetoxyphenyl)ethyl]-5, 6, 7, 8, 8-pentahydrochromone on the basis of the proton nuclear magnetic resonance (1H-NMR) spectrum, dihedral angle and circular dichroism (CD) spectral data.
Article
Three new kinds of phenylethyl chromone derivatives, named AH1A, AH2a and AH2b, were isolated from the crude AH1 (agarotetrol) and AH2 (isoagarotetrol) fractions of agalwood (Jinko)from Kalimantan. AH<1A> separated from the crude AH1 fraction through the process of acetylation was characterized as 2-[2-(4-methoxyphenyl)ethyl]-5α, 6β, 7β, 8α-tetraacetoxy-5, 6, 7, 8-tetrahydro-chromone, and AH2a and AH<2b>, from crude AH2 fraction, were established to be 2[2-(4-methoxyphenyl)ethyl]- and 2-[2-(2-hydroxyphenyl)ethyl]-5α, 6β, 7α, 8β-tetrahydroxy-5, 6, 7, 8-tetrahydrochromone, respectively.
Article
The fragrant sesquiterpene (−)-guaia-1(10),11-dien-15,2-olide (8), isolated from agarwood (Aquilaria agallocha Roxb.), was synthesized starting from (−)-1,10-epoxybulnesene, which is readily available from α-bulnesene in patchouli oil. The absolute configuration of the natural 8 was established by direct comparison of its optical rotation with that of the synthesized 8. It was found that (−)-2α-hydroxyguaia-1(10),11-dien-15-oic acid (9), a synthetic intermediate of 8, also occurs in agarwood.
Article
Degradative studies and physical measurements supported by an unambiguous synthesis of the derived ketone (XVa) have led to the assignment of a novel spiro-skeleton to agarospirol (Ia), a sesquiterpene alcohol isolated from the essential oil of infected agarwood (Aquilaria agallocha Roxb.). The corresponding carbon skeleton (VI) has been named agarospirane. Agarospirol is the second spiro-terpenoid to be isolated from Nature. The most probable stereochemistry of agarospirol appears to be as in XXXIX.
Article
Three new sesquiterpenes, (−)-guaia-1(10),11-dien-15-al, (−)-selina-3,11-dien-9-one, and (+)-selina-3,11-dien-9-ol, have been isolated from Aquilaria agollocha (agarwood). Their structures have been established on the bases of detailed spectroscopic analyses and synthesis. The odoriferous properties of these compounds are also described.
Article
Seven new sesquiterpenes, all of which have a guaiane skeleton, i.e. (−)-guaia-1(10),11-dien-15-ol, (−)-guaia-1(10),11-diene-15-carboxylic acid, methyl guaia-1(10),11-diene-15-carboxylate, (+)-guaia-1(10),11-dien-9-one, (−)-1,10-epoxyguai-11-ene, (−)-guaia-1(10),11-dien-15,2-olide and (−)-rotundone, have been isolated from Aquilaria agallocha (agarwood). Their structures have been established on the bases of detailed spectroscopic analyses and synthesis.
Article
Two new tri-2-(2-phenylethyl)chromones, tentatively named AH19a and AH19b, were isolated from agalwood ‘Jinkō’ and structurally characterized using 1H and 13C NMR spectra.
Article
From an agarwood (Aquilaria sp.; probably Aquilaria malaccensis Benth.) which is different from that obtained from Aquilaria agallocha Roxb., two new sesquiterpene alcohols, which we have named jinkoh-eremol (3) and jinkohol II (5), have been isolated, together with agarospirol (1), kusunol (2), and jinkohol (4), as major sesquiterpene constituents and their structures have been established.
Article
Four new compounds have been isolated from agarwood oil (Aquilaria agallocha Roxb.) and their structures confirmed by synthesis: (1R,2R,6S,9R)-6,10,10-trimethyl-ll-oxatricyclo[7.2.1.01,6]dodecane-2-spiro-2′-oxirane (1) (epoxy-β-agarofuran), (1S,2S,6S,9R)-6,10,10-trimethyl-11-oxatricyclo[7.2.1.01,6]dodecane-2-carbaldehyde (2), (E)-8,10-undecadien-2-one (3) and 2,t-3-dimethyl-r-2-(3-methyl-2-butenyl)-l-cyclohexanone (4, absolute configuration unknown). Several of their diastereoisomers, such as (1R,2S,6S,9R)-6,10,10-trimethyl-11-oxatricyclo [7.2.1.01,6]dodecane-2-spiro-2′-oxirane (5), (1S,2R,6S,9R)-6,10,10-trimethyl-11-oxatricyclo[7.2.1.01,6] dodecane-2-carbaldehyde (6), (Z)-8,10-undecadien-2-one (7) and racemic 2,c-3-dimethyl-r-2-(3-methyl-2-butenyl)-1-cyclohexanone (8, racemate) were also synthesized and fully characterized. The 13C NMR data of agarospirol (9), published earlier,1are corrected. The assignments are supported by 1D-INADEQUATE experiments.
Article
Six new nor-sesquiterpenoids with the 10-epi-eudesmane skeleton were isolated from agarwood oil (Aquilaria agallocha Roxb.): (2R,4aS)-2-(4a-methyl-1,2,3,4,4a,5,6,7-octahydro-2-naphthyl)-propan-2-ol (5a), (S)-4a-methyl-2-(1-methylethyl)-3,4,4a,5,6,7-hexahydronaphthalene (6), (S)-4a-methyl-2-(1-methylethylidene)-1,2,3,4,4a,5,6,7-octa-hydronaphthalene (7), (2R,4aS)-4a-methyl-2-(1-methylethenyl)-1,2,3,4,4a,5,6,7-octahydronaphthalene (8), (1R,6S, 9R)-6,10,10-trimethyl-11-oxatricyclo[7.2.1.01.6]dodecane (9) and (1R,2R,6S,9R)-6,10,10-trimethyl-11-oxatricyclo [7.2.1.01.6]dodecan-2-ol (10).
Article
Three new sesquiterpenic furanoids of the selinane group have been isolated from agarwood oil, obtained from the fungus infected plant Aquillaria agallocha Roxb. and their structures and absolute configurations determined (XXII, XX, XXXI) by degradative studies and physical measurements.
Article
The profile of the total extract of agarwood oil (Aquilaria agallocha Roxb.) is discussed and eight new sesquiter-penoids are presented: two with the eremophilane-skeleton (rel-(2R,8S,8aR)-2-(1,2,3,5,6,7,8,8a-octahydro-8,8a-dimethy1-2-naphthyl)-prop-2-en-1-ol (1, eremophila-9,11(13)-dien-12-ol) and rel-(3R,7R,9R,10S)-9,10-dimethyl-6-methylene-4-oxatricyclo[7.4.0.03,7]tridec-1-ene (2, 8,12-epoxy-eremophila-9,11(13)-diene)), one with the valencane-skeleton (rel-(2R,8S,8aR)-2-(1,2,6,7,8,8a-hexahyro-8,8a-dimethyl-2-naphthyl)-propan-2-ol (3, valenca-1(10),8-dien-11-ol)) and four with the vetispirane-skeleton (rel-(5R,10R)-(2-isopropylidene-10-methyl-spiro[4,5]dec-6-ene-6-carbaldehyde (4, vetispira-2(11),6-dien-14-al), rel-(5R,7R,10R)-2-isopropylidene-10-methyl-6-rnethylene-spiro[4.5]decan-7-01 (5, vetispira-2(11),6(14)-dien-7-01), rel-(1R,2R)-9-isopropyl-2-rnethyl-8-oxatricyclo[7.2.1.01,6]dodec-5-ene (6, 2,14-epoxy-vetispir-6-ene) and rel-(1R,2R)-(9-isopropyl-2-methyl-8-oxatricyclo[7.2.1.01,6]dodeca-4,6-diene (7, 2,14-epoxy-vetispira-6(14),7-diene)). 2-(1,2,3,5,6,7,8,8a-octahydro-8,8a-dimethyl-2-naphthyl)-propanal (8, valenc- or eremophil-9-en-12-al) is tentatively identified.
Article
Three fragrant sesquiterpenes have been isolated as major constituents from the wood of Aquilaria malaccensis and identified as α-agarofuran, (−)-10-epi-γ-eudesmol and oxo-agarospirol.
Article
Two new sesquiterpene aldehydes, (−)-selina-3,11-dien-14-al and (+)-selina-4,11-dien-14-al, methyl ester derivatives of three new sesquiterpene carboxylic acids, (−)-methyl selina-3,11-dien-14-oate, (+)-methyl selina-4.11-dien-14-oate, and (+)-methyl 9-hydroxyselina-4,11-dien-14-oate, and a new nor-sesquiterpene ketone, (+)-1,5-epoxy-nor-ketoguaiene, have been isolated from Aquilaria agallocha (agarwood). Their structures have been established on the bases of detailed spectroscopic analyses and synthesis. The occurrences of dehydrojinkoh-eremol and neopetasane in agarwood were also confirmed by comparison of their mass spectral data and Rinn, on capillary GC with those of synthesized samples. The odoriferous properties of some natural and synthesized sesquiterpenes are also described.
Article
Aquillochin, isolated from the whole plant of Aquilaria agallocha, has been shown to be a coumarinolignan, and a structure has been proposed on the basis of chemical and physical studies.
Article
In addition to the furanoid compounds reported previously, three more crystalline furanoids of the selinane group have been isolated from agarwood oil, obtained from the fungus infected plant Aquillaria agallocha Roxb. The structures and absolute configurations have been determined by their interconversions into the compounds previously reported.
Article
Three novel diepoxy tetrahydrochromones, oxidoagarochromones A (1), B (2), and C (3), were isolated from agarwood artificially produced by intentional wounding of Aquilaria crassna. Inductive production of these compounds was also confirmed at the early stage of wounding in A. sinensis and A. crassna. These diepoxy tetrahydrochromones would play an important role in understanding the biosynthesis of chromone derivatives in agarwood.
Article
The isolation of two sesquiterpenes, gmelofuran and agarol, from Aquilaria agallocha is described Gmelofuran has not been previously reported from this genus and the structure of agarol has been elucidated by physical methods and chemical reactions.
Article
A new tricyclic sesquiterpene, jinkohol, has been isolated from an agarwood (Aquillaria sp.) which is different from that obtained from Aquillaria agallocha. Its structure was shown to be 2β-hydroxy-(+)-prezizane by spectroscopic methods and by chemical transformation. The two kinds of agar