Agarwood Tree Research Articles

Chemical constituents and toxicity effects of leaves from several agarwood tree species (Aquilaria)

Chemical constituents and toxicity effects of leaves from several agarwood tree species (Aquilaria)

STUDY OF FERTILIZER (ORGANIC + INORGANIC) FORMULATION TO IMPROVE GUBAL AGARWOOD FORMATION IN KETIMUNAN TREE (Gyrinops versteegii)

A study of fertilizer formulation (organic + inorganic) to increase the formation of sapwood (gubal) on agarwood plants (Gyrinops versteegii), had done to find the best fertilizer formulation that capable of increase and accelerate either growth and agarwood formation of sapwood on agarwood trees. The first year of study was conducted in Marga Tabanan Village. The field research was Randomized Block Designed (3 groups) with single factor of treatment. The tested treatment were 6 formulation of compound fertilizers and a control (unfertilized treatment). The compound fertlizers consisted of urea, SP-36, KCl, local compost, and dolomite in varying doses. The fertilizer formulations were applied on 21 agarwood trees that previously inoculated with mixed inoculant of Fusarium solani and Rhisopus sp. Three months after inoculation, the data from the following parameters were measured and statistically analyzed: plant height, stem circumference, sapwood weight, resin content and soil chemical properties.The results showed that the tested fertilizer compound had significant effect on plant height, sapwood weight, and resin rendement. No significant effect of fertilizer compound measured on the stem circumference. The highest sapwood weights was obtained on C treatment (14.39 g). The highest resin yield was obtained on B treatment (3.91%) which was relatively the same as that on C treatment (3.85%). Thus, the best fertilizer formulation for either plant growth, agarwood formation or agarwood resin was C treatment (100 g urea + 100 g SP-36 + 100 g KCl) + (7.5 kg compost) + (75 g Dolomite) per tree.

The structure and development of interxylary and external phloem in Aquilaria sinensis

The structure and development of interxylary phloem (IP) and external phloem in Aquilaria sinensis were investigated using light and scanning electron microscopy. Complete IP strands were isolated, measuring 14 ± 4 mm in length and 417 ± 124 μm in width. The outer margin of IP was composed of two to three layers of fusiform parenchyma cells. The development of IP can be divided into five stages: 1) Locally IP starts its differentiation within a small segment of a broad cambial zone, at the cost of xylem differentiation. 2) Inward growth of IP advances, and fibres and sieve tubes differentiate. 3) IP is constricted by the encroachment of immature xylem cells between cambium and immature IP. 4) IP is isolated from the cambium and surrounded by immature, non-lignified xylem tissue. 5) IP is surrounded by lignified xylem tissue, and the fibres within IP become lignified.In all the phloem islands in a ten-year-old stem, sieve elements showed positive staining of callose with aniline blue. However, no staining of callose was observed in the external secondary phloem of agarwood trees collected from two different sites. No sieve tubes or sieve pores were detected by SEM observation of numerous serial cross and radial sections of the external phloem. We therefore conclude that sieve tubes are absent from the external phloem or extremely rare and that the transport of photosynthetic products in the stem of A. sinensis takes place in the interxylary phloem.

Characterization of the complete chloroplast genome of the vulnerable agarwood tree, Aquilaria yunnanensis (Thymelaeaceae)

Aquilaria yunnanensis S. C. Huang is a precious agarwood tree endemic to Yunnan Province of China. It is included in Category II of CITES. In this study, we reported its complete chloroplast genome de novo assembled from Illumina pair-end sequencing data. The plastome was a quadripartite circular with 174,885 bp in length, including one large single copy (LSC) region of 87,508 bp and one very short small single copy (SSC) region of 3351 bp, separated by two extremely expanded inverted repeat (IR) regions of 42,013 bp. The overall GC content of the genome was 36.7%, and the corresponding values of the LSC, SSC and IR regions were 34.9, 29.1 and 38.8%, respectively. The chloroplast genome encoded 142 genes, including 96 protein-coding genes, 38 tRNA genes, and eight rRNA genes. Phylogenetic analysis revealed that sampled species of Thymelaeaceae formed a monophyletic clade, in which A. yunnanensis and A. sinensis formed a sister clade to Daphne kiusiana.

Community forest management: Comparison of simulated production and financial returns from agarwood, tengkawang and rubber trees in West Kutai, Indonesia

Lahjie AM, Isminarti, Simarangkir BDAS, Kristiningrum, R, Ruslim Y. 2018. Community forest management: Comparison of simulated production and financial returns from agarwood, tengkawang and rubber trees in West Kutai, Indonesia. Biodiversitas 19: 126-133. Research was conducted in planted forests of agarwood (Aquilaria spp.) and tengkawang (Shorea macrophylla) and in plantations of natural rubber (Hevea brasiliensis) in West Kutai District, East Kalimantan Province, Indonesia. The research aimed (i) to find out the productivity of agarwood and tengkawang trees in mixed plantings (ii) to measure their rate of development in order to estimate the maximum Mean Annual Increment (MAI) for agarwood and tengkawang and (iii) to carry out a comparison with natural rubber production of the investment feasibility of planted forests of these trees using a financial analysis of Pay Back Period, Net Present Value (NPV), Net Benefit/ Cost (B/C) Ratio and Internal rate of Return (IRR). The research was based on measurements carried out in plots, 0.25 ha in extent, selected by systematic random sampling from three model plantations. Plantation Model I was a combination of agarwood and tengkawang in one piece of land in which the agarwood trees were planted at a spacing of of 5m x 2.5m and the tengkawang tree were also planted at a spacing of 5m x 2.5m. This means that there were a total of 200 agarwood saplings and 200 tengkawang saplings in the plot. Model II was the combination of agarwood and tengkawang in one piece of land, in which 167 agarwood saplings were planted and 166 tengkawang saplings were planted in a different planting arrangement (at the planting distance of 5m x 3 m). Model III was rubber trees in an area of 0.25 ha with 119 saplings. The data for natural rubber were collected in series from the farmers. The measurement variables for agarwood and tenkawang included the diameter and height of trees using series measurement until they reached 30 years and then the results were simulated. The research findings showed that in Model I, agarwood was found to have higher maximum MAI while in Model II, tengkawang was found to have higher maximum MAI. This was the result of a silvicultural technique in which thinning, maintenance and intermediate harvest were carefully controlled. These two models were feasible for business because the values of their IRR were 14% and 13.3% respectively, while in Model III, rubber cultivation was not feasible for business because the value of its IRR was only 4.7%.

Development of protocols for genomic library construction of Agarwood (Aquilaria malaccensis)

Siregar UJ, Maulana MI, Suharsono UW. 2017. Development of protocols for genomic library construction of Agarwood (Aquilaria malaccensis). Biodiversitas 18: 1150-1158. Agarwood is one of non timber forest products (NTFP) which has high economic value. Diminishing agarwood trees in natural forest due to intensive harvesting has shifted the production paradigm to forest plantation. In order to support agarwood tree improvement, investigation on the agarwood tree genomes and genes involved in agarwood production is highly needed through genomic library construction. This research aimed at establishing cloning protocols for genomic library construction of agarwood tree (Aquilaria malaccensis) until sequencing process. Genomic DNA was isolated using DNeasy Plant Mini Kit from Qiagen, then was digested with EcoR1, and was ligated to pGem®-T Easy vector system before it was finally transformed and was cloned to E.coli strain DH5α. Confirmation of DNA inserts was done using PCR colony with universal primer of SP6 and T7, plasmid isolation and also PCR plasmid and plasmid DNA digestion used Quick Plasmid Miniprep Kit from Thermofisher. Cloned A. malaccensis DNA fragments were sequenced and BLAST at NCBI site. The cloning successfully obtained five white colonies which contain inserted A. malaccensis DNA fragments with the size of 136-225 bp. PCR colony, plasmid isolation, PCR plasmid, and plasmid DNA digestion had confirmed the existence of inserted A. malaccensis DNA genome inside the bacteria cells. Sequencing and BLAST showed that DNA inserts from colony number 6, 8, and 9 were not similar with A. malccensis sequence that was recorded in NCBI, indicating that the genomic region in this library construction is different from the genomic DNA sequences of A. malaccensis in NCBI.

A review of chemistry, quality and analysis of infected agarwood tree (Aquilaria sp.)

Agarwood is a valuable oleoresin obtained from wounded tree of various genus of Thymelaeaceae family especially from Aquilaria species. Agarwood is regarded as most treasured non-timber forest product used in fragrances as well as medicines. Quality of agarwood plays an important role to define its commercial value. Different countries use different grading pattern to define the quality of agarwood. More than 250 compounds have been identified so far, mostly sesquiterpenoids, chromones and volatile aromatic compounds. GC–MS is the considered as a best method for the identification of chemical profile of the agarwood by various authors. Present review discusses the various methods used to determine quality of agarwood and chemical constituents of infected agarwood tree.

Evaluation of incense-resinous wood formation in agarwood (Aquilaria malaccensis Lam.) using sonic tomography

Incense-resinous wood of agarwood is a high-value non-timber forest product found in the trunk or branches of Aquliaria and Gyrinops species. Incense-resinous wood of agarwood is formed as a response to tree damage caused by wounding or fungal attack. Detection of such wood in trees has generally been carried out based on natural signs such as dark spots or black marks when peeling back tree bark, but these often yield uncertain results. Sonic tomography can be applied to predict the presence of incense-resinous wood in standing trees. The objective of this study was to evaluate sonic tomography at various trunk heights based on variations in the sound velocity associated with the presence of incense-resinous wood. Ten agarwood trees (Aquilaria malaccensis) were selected for this study; five trees were artificially inoculated with Fusarium solani fungus and the other five were untreated. The results showed that the height of the measurement did not significantly affect the propagation velocity of sound waves or the tomographic results. Sonic tomography revealed that prediction of the deteriorated zone which is indicative of incense-resinous wood formation was 1.1% greater in inoculated trees than in uninoculated trees.

Temporal and spatial expression of terpene synthase genes associated with agarwood formation in Aquilaria malaccensis Lam

The diseased wood, agarwood, from the tropical tree taxa Aquilaria, is famed for its unique fragrance and medicinal values, mainly due to its richness in secondary metabolites such as the sesquiterpenes. The presence of sesquiterpenes in high numbers and amounts correlates with agarwood of high quality. To understand the synthesis of this important compound, we cloned two candidate genes in the terpenoid synthesis pathway from Aquilaria malaccensis Lam., a major agarwood tree species. The genes encoding sesquiterpene synthase (AmSesTPS1) and δ-guaiene synthase (AmGuaiS1) were successfully cloned from callus RNA, using specific primers derived from transcriptomic data, in a reverse transcription PCR reaction. The full-length complementary DNA (cDNA) sequence of AmSesTPS1 was 1632 bp encoding for 544 amino acids, and AmGuaiS1 was 1644 bp encoding for 547 amino acids. Sequence alignment analysis showed that AmSesTPS1 shared between 99 to 100 % identity with sesquiterpene synthase from Aquilaria sinensis (Lour.) Spreng. while AmGuaiS1 shared between 95 to 99 % identity with δ-guaiene synthases from Aquilaria crassna Pierre ex Lecomte and A. sinensis. The genes were functionally characterised in a time course wounding experiment using 3-year-old living trees. Two types of wood samples were collected: (1) from wounded area (S1) and (2) from 5 cm below the wounded area (S2). AmSesTPS1 was highly expressed after 6 h post wounding for both S1 and S2, at a level three- to six-fold higher than that of the unwounded control (0 h), while AmGuaiS1 was induced after just 2 h of wounding (18- and 5.5-fold at S1 and S2, respectively), after which the expression of both genes was lowered. The average normalised expression of both genes at S1 and S2 indicates the genes were also upregulated in the distal area from the wounding site. It can be deduced that wounding triggers these two genes in the sesquiterpene synthesis pathway, which ultimately leads to agarwood formation.

Biological characterization of fungal endophytes isolated from agarwood tree Aquilaria crassna Pierre ex Lecomte

In recent years, a considerable number of studies on the role of microbes in agarwood production have been carried out in plants of the species Aquilaria. Based on the fact that there is a relationship between the microorganisms residing inside the plant and the agarwood formation, we isolated and characterized endophytic fungi associated with A. crassna samples collected from Southern Vietnam. Morphological identification and DNA barcoding analysis of the fungal endophytic isolates indicated that they were classified at least into three groups of diverse genera: Geotrichum, Fusarium and Colletotrichum belonging to families Dipodascaceae, Nectriaceae and Glomerellaceae, respectively. Noteworthy, Geotrichum candium strain SHTr1 isolated from a dark colored woody sample of agarwood was able to produce a fruity odor and exhibited a slight antimicrobial activity against the test bacterium Staphylococcus aureus. Another fungal isolate, Fusarium verticillioides SHTr3’s, showed a moderate antimicrobial activity against a test Gram positive bacteria Bacillus subtillis and S. aureus with MIC values at 50 μg.mL-1. At 200 μg.mL-1, the ethyl acetate extracts of fungal isolates F. verticillioides SHTr3 and Colletotrichum truncatum SHTrHc7 were found to have comparable scavenging abilities on DPPH-free radicals with 53.87 and 71.82%, respectively. The present results contribute to a depiction of a diverse fungal endophytic community in Vietnamese agarwood plant A. crassna and provide important information for further understanding of the role of endophytic fungi in agarwood formation and therapeutic applications of host plants in general.

Fungal Microbes Associated with Agarwood Formation

Agarwood is studied as the resinous secondary metabolites produced by the natural microbial infection. The current study investigated the range of microbial infection in agarwood trees collected from various parts of India. A total of 17 isolates were collected and identified based on the morphological and molecular studies. The study revealed that the agarwood was naturally infected with Aspergillus, Lasiodiploidia, Chaetomium, Fusarium and Penicillium species. Further studies on enzyme activities involved in the pathogenesis process showed the higher cellulase, ligninolytic and laccase activities in Aspergillus isolate AR13 when compared to other isolates. The current study has offered a potential opportunity to further strengthen the research on possible development of microbial strains for artificial inoculation in agar trees to induce agarwood formation.

POTENSI POHON PENGHASIL GAHARU BUDIDAYA DI KABUPATEN KAMPAR PROVINSI RIAU

Scarcity of agarwood trees in natural forests cause agarwood trade of all species be included Aquilaria malacensis into CITIES (Convention on International trade in Endangered Species of Wild Fauna and Flora) and limited exsport quota. Agarwood is a resinous wood and has the benefit of such ingredients as perfumes and medicines. High economic value of Eaglewood cause increased community interest for cultivation of Gaharu plants. This research was done in January to March 2015 in Pangkalan Baru, Siak Hulu subdistrict and Kuapan, Tambang subdistrict, Kampar district, Riau Province. The materials used were map, related research, camera , GPS, compass, altimeter, measuring tape, hagameter, talysheet, etc. Field of observations with searching information about cropping in cultivation of agarwood, identification of farmers and cropping patterns. Survey of agarwood tree conducted by purposive sampling method. Data obtained by making a plot with measuring 20 x 20 m plated on transect with sampling intensity by 20%. The results of research on cropping pattern was monoculture and multiculture. Multiculture was in the rubber plants. The age of agarwood trees in monokultur was 19 years old., whereas multiculture between 2-5 year. Potential agarwood trees in monocultural was 19 m³ but multicultue can not be due to plant cause age>5 years.

The Role of Phenolics in Agarwood Formation of Aquilaria crassna Pierre ex Lecomte and Aquilaria microcarpa Baill trees

Phenolic is well known as a secondary metabolite that plays an important role in plant defense system. Information about the fungi-impeded role of secondary metabolite is important in achieving success of artificial agarwood production, in that fungi induction imparted to the selected potential trees will be more effective and efficient. This research was aimed to investigate the correlation of agarwood tree phenolics in relation with the susceptibility of corresponding trees to Fusarium solani attack in the formation of agarwood and observing total phenolics content of Aquilaria crassna and Aquilaria microcarpa trees prior to inoculation. Twenty trees of A. microcarpa at Carita, a Forest Area for Special Function (FASF) and ten of A. crassna at Dramaga Research Forest were inoculated with isolate of F. solani in spiral pattern around their stem from ground level to about 1.5 m in height. Prior to inoculation, wood strips were taken off from the stem for total phenolics content. The result revealed that total phenolics content and infection area tended to have a negative correlation. Since the quantity of agarwood is highly related with the infection area, then trees with lower phenolics content should be selected for the more effective and efficient artificial agarwood production.

Phytochemical and antimicrobial screening of extracts of Aquilaria agallocha Roxb.

Aquilaria agallocha Roxb. is an endangered economic plant used for production of agar wood worldwide. The aqueous and methanol extracts along with dry powder of leaf and bark of the plant was screened for the presence of phytochemicals. Also they were tested for antibacterial activity against pathogenic bacteria such as Shigella flexneri, Bacillus brevis, Pseudomonas aeruginosa and Bacillus subtilis. The result indicates the presence of alkaloids, anthroquinones, triterpenoids, tannins, fixed oils and fats and glycosides in methanol extracts whereas saponins, fixed oils and fats, alkaloids and triterpenoids were found in the aqueous extracts. The highest alkaloid content was in the aqueous extract of the bark (0.06%). The saponin content was found to be high in the leaf powder (0.169%). The bark powder contained 0.067% glycosides while the leaf powder had 0.036%. The leaf powder had the highest amount of carbohydrates (19.42 mg/g dry weight), protein (24.37 mg/g DW) and amino acids (12.1 mg/g DW). The methanol extract of the leaf gave the highest zone of inhibition against B. subtilis (19 mm). All other extracts showed moderate zones of inhibition (14 - 18 mm) against all the bacteria tested. The present study has proved the usefulness of agarwood tree for medicinal purposes. The presence of phytochemicals indicates its potential as a source of useful drugs.

Phytochemical and antimicrobial screening of extracts of Aquilaria agallocha Roxb.

Aquilaria agallocha Roxb. is an endangered economic plant used for production of agar wood worldwide. The aqueous and methanol extracts along with dry powder of leaf and bark of the plant was screened for the presence of phytochemicals. Also they were tested for antibacterial activity against pathogenic bacteria such as Shigella flexneri, Bacillus brevis, Pseudomonas aeruginosa and Bacillus subtilis. The result indicates the presence of alkaloids, anthroquinones, triterpenoids, tannins, fixed oils and fats and glycosides in methanol extracts whereas saponins, fixed oils and fats, alkaloids and triterpenoids were found in the aqueous extracts. The highest alkaloid content was in the aqueous extract of the bark (0.06%). The saponin content was found to be high in the leaf powder (0.169%). The bark powder contained 0.067% glycosides while the leaf powder had 0.036%. The leaf powder had the highest amount of carbohydrates (19.42 mg/g dry weight), protein (24.37 mg/g DW) and amino acids (12.1 mg/g DW). The methanol extract of the leaf gave the highest zone of inhibition against B. subtilis (19 mm). All other extracts showed moderate zones of inhibition (14 - 18 mm) against all the bacteria tested. The present study has proved the usefulness of agarwood tree for medicinal purposes. The presence of phytochemicals indicates its potential as a source of useful drugs.

Production of Agarwood Essential Oil: Study on Effectiveness Pre-Treatment Technique of Hydrodistillation Extraction

There are many uses of agarwood trees in a number of countries around the world. However, lack in extractionprocess efficiency was affected to the lower product quality and oil yield. Therefore, this research was aimed toinvestigate the effect of pre-treatment techniques of soaking with water and soaking with three fungi onagarwood oil yield. The oils produced were compared with industrial samples. Analysis of chemical compoundsis done by using Gas Chromatography-Flame Ionization Detector (GC-FID) and Gas Chromatography-MassSpectrometry (GC-MS). As a result, the sample treated with fungi Phanerochaete chrysosporium achieved thehighest average oil yields of 0.58% with content of 80.13% of total chemical compounds compared to sampletreated with water only consist of 0.27% oil yield and 72.58% of total chemical compounds was detected. Thesample soak with fungi is more advantageous than soak with water in terms of oil productivity, energy savingand efficiency process. The main component present in all parameter studied were epoxybulnesene (1.64%-7.54%), tetradecanal (1.02%-6.10%), agarospirol (0.29%-1.34%), bulnesol (0.59%-8.07%), selina-3,11-dien-9-ol (1.10%-4.02%), oxo-agarospirol (1.12%-10.80%) and eudesmol (0.19%-9.17%).