Search Results (63)

In this study, we applied eight different light quality treatments and investigated their effects on the proliferation and physiological characteristics of Aquilaria sinensis group-cultivated seedlings in order to screen the best light quality for optimizing group-cultivation fast multiplication technology. The results showed that the highest multiplication rates were obtained with blue light and red light, which were significantly higher than those of white light. Blue light was the most effective in promoting the synthesis of photosynthetic pigments, while red light and blue violet light were favorable for the accumulation of soluble sugars. Correlation analysis showed that the multiplication rate was significantly and positively correlated with plant height, chlorophyll b, total chlorophyll, and soluble sugar content. The comprehensive evaluation indicated that blue light, blue-violet light, and red light was most suitable for fostering proliferation of, and physiological status improvement in, group-cultivated A. sinensis seedlings, with their superior performance likely attributable to the combined effects of specific spectral properties and appropriate photosynthetic photon flux density (PPFD) levels. The results of this study provide technical support for light environment regulation for the efficient and rapid propagation of group-cultured A. sinensis seedlings. Full article

Aquilaria sinensis (Lour.) Gilg, the exclusive botanical source of Chinese agarwood, holds significant medicinal value. This study investigated the agarwood-inducing potential of a Fusarium strain obtained through prior isolation work. Through integrated morphological characterization and molecular phylogenetic analysis, the strain was conclusively identified as Fusarium equiseti. GC-MS analysis revealed that fungal inoculation induced the synthesis of characteristic sesquiterpenes and aromatic compounds consistent with natural agarwood profiles. Quantitative determination demonstrated progressive accumulation of agarotetrol, a key quality marker, reaching 0.034%, 0.039%, and 0.038% at 2, 4, and 6 months post-inoculation, respectively—significantly exceeding levels from physical wounding (p < 0.05) and PDA control treatments. Histological examination showed characteristic yellow-brown oleoresin deposits concentrated in the inner phloem, mirroring the anatomical features of wild-type agarwood. Critical quality parameters measured in December-harvested samples included ethanol extractives (17.69%), chromone derivatives 2-[2-(4-methoxyphenyl) ethyl] chromone, and 2-(2-phenylethyl) chromone (2.13%), all meeting or surpassing the specifications outlined in the National Standard for Agarwood Classification (LY/T 3223-2020). These comprehensive findings establish F. equiseti as a promising microbial agent for sustainable agarwood production in A. sinensis plantations. Full article

Heortia vitessoides Moore (Lepidoptera: Pyralidae), the dominant outbreak defoliator of Aquilaria sinensis (Myrtales: Thymelaeaceae, the agarwood-producing tree), poses a severe threat to the sustainable development of the agarwood industry. Current research has preliminarily revealed its biological traits and gene functions. However, significant gaps persist in integrating climate adaptation mechanisms, control technologies, and host interaction networks across disciplines. This review systematically synthesizes the multidimensional mechanisms underlying H. vitessoides outbreaks through the logical framework of “Fundamental Biology of Outbreaks—Environmental Drivers—Control Strategies—Molecular Regulation—Host Defense.” First, we integrate the biological characteristics of H. vitessoides with its climatic response patterns, elucidating the ecological pathways through which temperature and humidity drive population outbreaks by regulating development duration and host resource availability. Subsequently, we assess the efficacy and limitations of existing control techniques (e.g., pheromone trapping, Beauveria bassiana application), highlighting the critical bottleneck of insufficient mechanistic understanding at the molecular level. Building on this, we delve into the molecular adaptation mechanisms of H. vitessoides. Specifically, detoxification genes (e.g., HvGSTs1) and temperature stress-responsive genes (e.g., HvCAT, HvGP) synergistically enhance stress tolerance, while chemosensory genes mediate mating and host location behaviors. Concurrently, we reveal the host defense strategy of A. sinensis, involving activation of secondary metabolite defenses via the jasmonic acid signaling pathway and emission of volatile organic compounds that attract natural enemies—an “induced resistance–natural enemy collaboration” mechanism. Finally, we propose future research directions: deep integration of gene editing to validate key targets, multi-omics analysis to decipher the host–pest–natural enemy interaction network, and development of climate–gene–population dynamics models. These approaches aim to achieve precision control by bridging molecular mechanisms with environmental regulation. This review not only provides innovative pathways for managing H. vitessoides but also establishes a paradigm for cross-scale research on pests affecting high-value economic forests. Full article

This study investigates the main insects and endophytic fungi that promote the formation of agarwood in Aquilaria sinensis (Lour.) Spreng. and elucidates the effects and mechanisms of different ‘insect + fungus’ combinations on agarwood formation. The results showed that 16 strains of endophytic fungi were isolated from A. sinensis. Fusarium solani, Penicillium chrysogenum, Fusarium equiseti, and Phaeoacremonium alvesii were identified as dominant fungi promoting agarwood formation, while Nadezhdiella cantori was recognized as the dominant insect facilitating this process. The optimal ‘insect + fungus’ combination was Nadezhdiella cantori + Fusarium equiseti. The average agarotetrol contents were 0.046% and 0.054% in February and June, respectively, which were significantly higher than those in cold drilling, fungal-only, and insect-only treatments. RNA sequencing revealed 23,801 differentially expressed unigenes in cjYB1Z4 (optimal combination) versus control BMZ. Upregulated unigenes were enriched in isoflavone biosynthesis, flavonoid biosynthesis, and sesquiterpenoid and triterpene biosynthesis. Fifty sesquiterpene-related differential unigenes encoded seven key enzymes in the MVA pathway, seven key enzymes in the MEP pathway, and seven terpene synthases. Co-expression network analysis indicated that transcription factors (e.g., WRKY33, ABF, WRKY2) potentially regulate agarwood sesquiterpene formation. This work elucidates preliminary effects and molecular mechanisms of insect- and fungi-induced agarwood formation in A. sinensis, advancing agarwood induction technology. Full article

Aquisinenins G–I (1–3), three new 2-(2-phenylethyl)chromone-sesquiterpene hybrids, were isolated from the ethanol extract of Hainan agarwood derived from Aquilaria sinensis. Spectroscopic techniques, such as ¹D and ²D NMR and HRESIMS, were used to determine their structures. Experimental and computed ECD data were compared to confirm their absolute configurations. Compounds 1–3 are uncommon dimeric derivatives of 2-(2-phenylethyl)chromone-sesquiterpene, characterized by the fusion of 5,6,7,8-tetrahydro-2-(2-phenylethyl)chromone with agarofuran or agarospirane-type sesquiterpene units by an ester linkage. Compound 1 inhibited nitric oxide production in lipopolysaccharide-stimulated RAW264.7 cells, showing an IC₅₀ value of 22.31 ± 0.42 μM. The neuroprotective effects of compounds 1 and 3 against H₂O₂-induced apoptosis were assessed in human neuroblastoma SH-SY5Y cells. Compound 1 demonstrated cytotoxicity with IC₅₀ values of 72.37 ± 0.20 μM against K562 and 61.47 ± 0.22 μM against BEL-7402, while compounds 2 and 3 showed cytotoxicity across all five tested human cancer cell lines. Full article

Aquilaria sinensis (Lour.) Spreng. is an economically important tree specie that produces agarwood, a valuable medicinal and aromatic resin, when injured. However, its large-scale cultivation has led to confusion regarding its resources and genetic backgrounds, hindering the conservation and management of A. sinensis accessions. This study systematically developed and validated simple sequence repeat (SSR) molecular markers by using whole-genome resequencing (WGR) data from 60 A. sinensis accessions to elucidate their genetic diversity and population structure. A total of 56,657 SSR sequences (24,430 loci) were identified, which were dominated with dinucleotide repeat motifs (73.59%). After stringent quality control, 46 high-quality SSR loci were obtained, and 93 primer pairs were designed for amplification validation. Ultimately, 20 primer pairs with stable amplification and high polymorphism were selected, of which 11 exhibited high polymorphism (polymorphic information content: 0.554–0.688). These 20 primer pairs identified a total of 121 alleles, with an average of 6 alleles per locus. These primers successfully classified 149 A. sinensis accessions into three subpopulations, achieving a discrimination rate of 95.97%. The analysis of molecular variance revealed that genetic variation within the individuals accounted for 84% of the total variation. This study establishes a rapid and efficient SSR-based method by leveraging resequencing data for large-scale marker discovery in A. sinensis. It further provides a robust technical framework for the conservation and sustainable utilization of this valuable species. Full article

Background/Objectives: Agarwood has a good neuroprotective effect and is often used to relieve anxiety and treat insomnia. This study compared the similarities and differences in the chromone components of two types of agarwood. It further investigated the absorption and brain distribution characteristics of these components in rats and their neuroprotective effects mediated through anti-neuroinflammatory pathways. Methods: This study confirmed, through ITS2 barcoding and chloroplast genome analysis, that both the ordinary and Qi-Nan agarwood are derived from Aquilaria sinensis. A comparative analysis of chromones in ethanol extracts derived from ordinary and Qi-Nan agarwood, as well as those capable of penetrating the blood-brain barrier in vivo, was conducted using UPLC-Q-TOF-MS. Subsequently, an in vitro neuroinflammatory model was established via lipopolysaccharide (LPS)-stimulated BV-2 cells to evaluate the anti-neuroinflammatory activity of differential chromones. Results: UPLC-Q-TOF-MS characterization revealed the chromone components in the two types of agarwood: A total of 81 chromone compounds were identified in the ethanol extracts of ordinary agarwood (OAE) (20 THPECs, 42 FTPECs, and 19 BI), while 41 were identified in the ethanol extracts of Qi-Nan agarwood (QNE) (11 THPECs and 30 FTPECs). Pharmacokinetic analysis in rats showed that 14 components from OAE (eight THPECs and six FTPECs) penetrated the rat serum, and 10 of these 14 components penetrated the blood–brain barrier (BBB). Twelve FTPECs from QNE penetrated the rat serum, all of which penetrated the BBB. The total peak area of the total ion current (TIC) was calculated for the samples, and the TIC of the serum was compared to that of the brain tissue from the same rat to roughly estimate the ratio. The results demonstrated that the capability of FTPECs to traverse the blood–brain barrier is substantially superior to that of THPECs. Correspondingly, only FTPECs were detected using DESI-MS imaging; no THPECs were detected in rat brain tissue, and DESI-MS imaging localized FTPECs to neuroanatomic regions (cerebral cortex, thalamus, and hippocampus). In vitro neuroinflammatory assays revealed the superior anti-inflammatory efficacy of QNE over OAE (IL-6/TNF-α suppression, p < 0.05), correlating with its FTPEC-rich composition. Conclusions: Structure–activity relationships identified FTPECs as potent inhibitors of pro-inflammatory cytokines, exhibiting enhanced BBB penetration (blood–brain relative abundance > 1). These findings establish FTPECs as prioritized candidates for CNS-targeted therapeutics, with QNE’s pharmacological superiority attributed to its FTPEC dominance and optimized BBB transit capacity. Full article

In this study, Aquilaria sinensis ‘Qinan’, a strain of A. sinensis that easily forms agarwood, was selected and propagated by grafting seedlings. Existing research has mainly focused on the characteristics of agarwood formation, but little attention has been paid to the growth characteristics of A. sinensis ‘Qinan’. In this study, the growth rate, photosynthetic capacity, leaf size, carbon and nitrogen contents, and antioxidant capacity were evaluated during the early growth stage in A. sinensis ‘Qinan’ and A. sinensis grafted seedlings. Compared with A. sinensis, A. sinensis ‘Qinan’ exhibited higher net photosynthetic rate (9.2 μmol m⁻² s⁻¹ in A. sinensis ‘Qinan’ and 7.8 μmol m⁻² s⁻¹ in A. sinensis) in the mature leaf. There were higher contents of secondary metabolites such as flavonoids and phenols, with stronger antioxidant capacity in A. sinensis ‘Qinan’. Larger leaf area (43.9 cm² in A. sinensis and 30.1 cm² in A. sinensis ‘Qinan’), higher nitrogen content (24.9 mg kg⁻¹ in A. sinensis and 23.7 mg kg⁻¹ in A. sinensis ‘Qinan’) in young leaves, faster growth rate, and larger biomass were observed in A. sinensis. The results indicate that differences exist in nutrient distribution during the growth process of A. sinensis ‘Qinan’ and A. sinensis, with more substances being used to synthesize defensive secondary metabolites in A. sinensis ‘Qinan’. Full article

Aquilaria spp. are a highly valuable plant species found in the Chinese herbal medicine and agarwood fragrance supplement industries for fumigation, combustion and perfume. The phytochemical composition of agarwood oils (extracts) was derived from Aquilaria sinensis and its subspecies ‘Qi-Nan’ using supercritical CO₂ extraction technology. Gas chromatography connected with a mass spectrometry apparatus was employed for qualitative and quantitative analyses. Comparing the agarwood oils from six planting areas, 12 common components were obtained, among which sesquiterpenes and chromones had the highest relative content. Genetic and environmental factors had the greatest impact on the three chromones, especially on 2-phenyl-4H-chromen-4-one. According to the PCA and PLS-DA models, the ‘Qi-Nan’ was derived from a variety selected from the native A. sinensis, and the difference in the volatile components was able to indirectly prove that it was genetically heterogeneous with the native A. sinensis. Using the 73 components obtained from GC–MS analysis, the VIP values and S-plots were generated using the OPLS-DA model. Seven components with VIP values > 1.0 were selected from two groups of agarwood oils of the native A. sinensis and ‘Qi-Nan’ subspecies. In addition, by analyzing 12 common components, the differential components with VIP values > 1 were 2-phenyl-4H-chromen-4-one and 2-(4-methoxyphenethyl)-4H-chromen-4-one. Chromones were the main component of agarwood oils extracted by supercritical CO₂, and 2-phenyl-4H-chromen-4-one could be used as a volatile marker, especially in the ‘Qi-Nan’ subspecies, where this marker exhibited more prominent characteristics. Full article

In recent years, some new “Qi-Nan” clones of Aquilaria sinensis with the characteristics of easy induction and high-quality agarwood have been obtained, through the cultivation and propagation of grafted seedlings. These clones are used for the intensive production of high-quality agarwood. The speed of resin formation and yield are crucial for the development of the agarwood industry. The differences in yield and chemical composition among different Qi-Nan clones and induction times are worth investigating. While the chemical composition differences between Qi-Nan and ordinary A. sinensis have been extensively studied, the effects of induction time coupled with different Qi-Nan clones on the chemical composition of Qi-Nan agarwood remain insufficiently explored. This study compared the changes in the chemical composition of four “Qi-Nan” clones of A. sinensis after 6, 12, and 24 months of induction through GC-QTOF-MS, the chemical composition and structure types of the four “Qi-Nan” clones were mainly 2-(2-phenylethyl)chromone derivatives (PECs) and Sesquiterpenoids (SESs), with the prolongation of induction time, the content of SESs increased, while the content of PECs decreased. Both the differences among clones and the induction time of “Qi-Nan” agarwood influence its chemical composition, which in turn affects the quality of the agarwood. Among these factors, induction time has a greater impact on the production of PECs in agarwood. The prolongation of induction significantly enhanced the yield of “Qi-Nan” agarwood and exhibited an inducing effect on the production of 2-(2-phenylethyl) chromone and 2-(2-4 phenylethyl)chromone. Compared with the agarwood obtained after 6 and 12 months of induction, the agarwood of “Qi-Nan” after 24 months of induction exhibited superior quality. The induction time for high-quality agarwood from the XGY clone was shorter (12 months) compared to the RH, YYZ, and AS clones (24 months). The study underscores that optimizing induction time and selecting suitable “Qi-Nan” clones can significantly enhance agarwood yield, quality, and production efficiency. Full article

Background/Objectives: Microorganisms such as bacteria, viruses, and fungi are frequently the cause of infections. Antimicrobial agents, such as antibiotics, antivirals, and antifungals, are used to target and eliminate these infectious agents. On the other hand, inflammation is a natural response of the immune system to injury, infection, or irritation. Although herbal remedies have been used to treat these conditions for centuries and can be effective in certain situations, it is crucial to use them with caution. Not all herbal remedies are supported by scientific evidence, and their safety and efficacy can vary. Thus, we conducted this review to determine the potential health benefits of agarwood as an antimicrobial and anti-inflammatory agent. Methods: Three databases (PubMed, Scopus, and Google Scholar) were used to search for original papers submitted between 2013 and 2023, using the Medical Subject Heading (MeSH) terms “agar-wood” crossed with the terms “antimicrobial” and/or “anti-inflammatory”. Synonyms and relevant search terms were also searched. Results: The most-studied agarwood for antimicrobial and anti-inflammatory agents is Aquilaria sinensis. Some studies have shown its potential application as a potent inhibitor of fungi, including Lasiodiplodia theobromae, Fusarium oxysporum, and Candida albicans. Moreover, it is capable of inhibiting Bacillus subtilis and Staphylococcus aureus activities. Several chromones detected in agarwood have been shown to inhibit NF-κB activation, LPS-induced NO production, and superoxide anion generation. In conclusion, more research is needed, particularly regarding future intervention studies, to enhance our knowledge and understanding of agarwood and its isolates. Conclusions: This review reveals that despite the absence of clinical trials, agarwood exhibits antimicrobial and anti-inflammatory properties. Full article

In recent years, plantations of Aquilaria sinensis in China have been dominated by Qi-nan, yet there remains limited research on the growth evaluation and breeding of these clones. In this study, a multi-point joint variance analysis, an additive main effect and multiplicative interaction (AMMI) model, a weighted average of absolute scores (WAASB) stability index, and a genotype main effect plus a genotype-by-environment interaction (GGE) biplot were used to comprehensively analyze the yield, stability, and suitable environment of 25 3-year-old Qi-Nan clones from five sites in southern China. The results showed that all the growth traits exhibited significant differences in the clones, test sites, and interactions between the clones and test sites. The phenotypic variation coefficient (PCV) and genetic variation coefficient (GCV) of the clones’ growth traits at the different sites ranged from 16.56% to 32.09% and 5.24% to 27.06%, respectively, showing moderate variation. The medium–high repeatability (R) of tree height and ground diameter ranged from 0.50 to 0.96 and 0.69 to 0.98, respectively. Among the clones, Clones G04, G05, G10, G11 and G13 showed good growth performance and could be good candidates for breeding. Environmental effects were found to be the primary source of variation, with temperature and light primarily affecting growth, while rainfall influenced survival and preservation rates. Yangjiang (YJ) was found to be the most suitable experimental site for screening high-yield and stable clones across the different sites, whereas the tree height and ground diameter at the Chengmai (CM) site were significantly higher than at the other sites, and the Pingxiang (PX) and Zhangzhou (ZZ) sites showed poor growth performance. The findings suggest that Qi-nan clones are suitable for planting in southern China. There were also abundant genetic variations in germplasm resources for the Qi-nan clones. The five selected clones could be suitable for extensive planting. Therefore, large-scale testing is necessary for determining genetic improvements in Qi-nan clones, which will be conducive to the precise localization of their promotion areas. Full article

Heortia vitessoides (Lepidoptera: Crambidae) is a severe pest of Aquilaria plants, which produce high-priced agarwood. The larval stage of this pest is gregarious, usually forming large aggregates during young instars and becoming solitary during the fifth instar. We hypothesize that the cuticle chemicals of young-instar H. vitessoides larvae could promote larval aggregating, whereas the cuticle chemicals of late-instar larvae would no longer attract young-instar larvae. In this study, two-choice tests were conducted to evaluate the effect of cuticle extracts of second- and fifth-instar H. vitessoides larvae on the aggregation preference of second-instar larvae. Results show that significantly more larvae aggregated on the leaves treated with the hexane extract of second-instar H. vitessoides larvae than on untreated leaves. However, the hexane extract of fifth-instar larvae had no significant effect on the aggregation preference of the second-instar conspecific larvae. Interestingly, acetone extracts of both second- and fifth-instar H. vitessoides larvae repelled the second-instar conspecific larvae throughout the 8 h experiment. Our study shows that cuticle chemicals of H. vitessoides larvae may play a role in the group dynamics of this pest, which may contribute to screening novel attractants and repellents for H. vitessoides. Detailed chemical analyses of the extracts and identification of the compounds involved in larval attracting and repelling would be valuable in future studies. Full article

Xylem-associated fungus can secrete many secondary metabolites to help Aquilaria trees resist various stresses and play a crucial role in facilitating agarwood formation. However, the dynamics of endophytic fungi in Aquilaria sinensis xylem after artificial induction have not been fully elaborated. Endophytic fungi communities and xylem physio-biochemical properties were examined before and after induction with an inorganic salt solution, including four different times (pre-induction (0M), the third (3M), sixth (6M) and ninth (9M) month after induction treatment). The relationships between fungal diversity and physio-biochemical indices were evaluated. The results showed that superoxide dismutase (SOD) and peroxidase (POD) activities, malondialdehyde (MDA) and soluble sugar content first increased and then decreased with induction time, while starch was heavily consumed after induction treatment. Endophytic fungal diversity was significantly lower after induction treatment than before, but the species richness was promoted. Fungal β-diversity was also clustered into four groups according to different times. Core species shifted from rare to dominant taxa with induction time, and growing species interactions in the network indicate a gradual complication of fungal community structure. Endophytic fungi diversity and potential functions were closely related to physicochemical indices that had less effect on the relative abundance of the dominant species. These findings help assess the regulatory mechanisms of microorganisms that expedite agarwood formation after artificial induction. Full article

Agarwood is a highly sought-after resinous wood for use in medicine, incense, and perfume production. However, the process of agarwood formation is slow. In this study, the induction of agarwood formation in three-year-old Aquilaria sinensis “Qinan” trees through treatment with ethephon, hydrogen peroxide, sodium chloride, distilled water, and wounding was investigated. The results showed that the starch content significantly decreased and that the soluble sugar content significantly increased during the process of agarwood formation, with no significant difference between the different treatment groups. The net photosynthetic rate significantly decreased. Except for the sodium chloride treatment, the total antioxidant capacity and the contents of flavonoids and phenols significantly increased during the process of agarwood formation. The essential oil yield of the ethephon and hydrogen peroxide treatment groups was significantly higher than that of the other treatment groups, with the highest essential oil yield in the ethephon treatment group. Compared to the control group, salt treatment produced the lowest essential oil yield of agarwood. The results indicate that appropriate concentrations of ethephon and hydrogen peroxide can promote the formation of agarwood in A. sinensis “Qinan”. Full article