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ISSN : 2693 6356 

2022 | Vol 5 | Issue 2 

 
 

 

 

 

Oral Agarwood's Potential as a Treatment for Chronic Inflammatory 

Diseases 
Dr. Priyanka Shrenik Gugale 

Assistant Professor 

Homoeopathic Medical College & Hospital, Jalgaon 

 

Abstract: Gingivitis, in one form or another, may affect almost everyone. Many things, like not cleaning your teeth enough 

or an immune system that isn't working properly, may lead to gingivitis, a kind of periodontal disease. Periodontitis, which is 

irreversible, may develop from gingivitis if left untreated. Finding a medication that may decrease inflammation with fewer 

adverse effects, as an alternative to existing anti-inflammatory medicines, is a significant avenue of gingivitis research. 

Traditional Chinese medicine makes extensive use of agarwood for its therapeutic properties. According to prior research on 

agarwood's chemical composition and pharmacological actions, sesquiterpene and quercetin, two of the plant's active 

components, can reduce inflammation. Nevertheless, agarwood's potential in alleviating chronic inflammation in the mouth, 

including gingivitis, has received little scientific attention. This research aimed to outline the potential mechanism of act ion of 

agarwood on gingivitis by reviewing and synthesizing the relevant domestic and international literature. To determine how 

agarwood could work to reduce chronic inflammation in the mouth, we looked at the anti-inflammatory, antioxidant, 

antibacterial, analgesic, and immunological functions of its active ingredients in gingivitis. If you are interested in using 

agarwood or one of its byproducts to alleviate inflammation in your mouth, this review will serve as a useful theoretical 

reference. 

Keywords: Agarwood, Gingivitis, Anti Inflammation, Bacteriostasis, Analgesia 

 

 

 

Introduction 

The resinous heartwood produced by trees belonging to the 

genus Aquilaria Lam is known as agarwood. According to 

taxonomy, it is a member of the Daphne family. Aquilaria 

Sinensis, scientifically known as Aquilariasinensis (Lou.) 

Gilg, is the primary component of agaricus grown in China 

[1]. Taiwan, Guangdong, Guangxi, and Hainan Island are 

the primary production regions [2]. Traditional medicine 

practitioners have relied on agarwood for centuries to 

alleviate a variety of symptoms, including heart problems, 

nausea, vomiting, and shortness of breath [3]. Traditional 

Chinese medicine also heavily relies on agarwood. It is 

anthelmintic and has a sedative effect. Stomach pain is 

another common usage for it.  

 

issues, a runny nose, watery eyes, rheumatism, and a high 

temperature [4, 5]. The unique scent components of 

agarwood are refined and concentrated to create agarwood 

essential oil. According to studies, its primary components 

include chemicals that prevent the development of many 

illnesses, such as sesquiterpenes, aromatics, chromones, 

fatty acids, and others. Its many pharmacological effects 

have been carefully engineered [6]. Inflammation of the 

gums brought on by bacteria and tartar buildup in the 

gingival groove is known as gingivitis. Progression to 

periodontitis is possible if prompt treatment is not provided. 

Agarwood is a local specialty with great therapeutic 

potential and great scientific value. It would be wise to 

investigate its history, potential uses, and integration with 

diverse goods in a range of formats to fulfill its function.  

 

 

1. Anti-Inflammatory Activity 

Gingivitis is a chronic inflammatory disease, manifested 

as gingival swelling, bleeding and pain. Agarwood has 

anti-inflammatory effect, chromone and sesquiterpene are 

the main anti-inflammatory related active components 

isolated from agarwood essential oil [7]. The anti-

inflammatory active components of agarwood can play an 

anti-inflammatory role by inhibiting the synthesis of 

inflammatory mediators such as 5-hydroxytryptamine, 

histamine and prostaglandin [8]. In molecular docking and 

ADME studies, it was found that several major 

sesquiterpenoids in agarwood essential oil have strong 

affinity for major anti-inflammatory receptors and 

immunoregulatory receptors [9]. Some sesquiterpenoid 

monomers also inhibit the release of NO induced by 

lipopolysaccharide in the anti inflammatory activity 

screening model of mouse monocyte macrophages RAW 

264.7 in vitro [10, 11]. It was found that sesquiterpenoids 

in agarwood essential oil inhibit the expression of p-

STAT3, thereby reducing the production of 

proinflammatory cytokine IL-1 β and IL-6, releasing anti-

inflammatory mediators [12]. In addition, some scholars 

confirmed through experiments that 2 

- (2-phenylethyl) chromone derivatives in agarwood can 

inhibit STAT1/3 and NF- κ B signal pathway showed 

significant anti-inflammatory effect [2]. Tryptone 

derivatives can also inhibit the production of carbon 



monoxide in macrophages induced by lipopolysaccharide 

[1]. In addition, the alcohol extracts of the flowers, seeds, 

pericarp and leaves of agarwood contain n-hexadecanoic 

acid and squalene [1]. Hexadecanoic acid can inhibit 

phospholipase A2 by binding to the active site of 

phospholipase A2 to control inflammation [9]. Some 

researches have found that agarwood essential oil has 

significant anti-inflammatory activity when administered 

by gavage. The anti-inflammatory activity of agarwood 

essential oil has been confirmed. The incidence of 

periodontal tissue inflammation is high in systemic 

inflammation. At present, there is no precedent for the 

treatment of periodontitis with agarwood composition. The 

anti-inflammatory function of agarwood extract provides a 

theoretical basis for its application in the treatment of 

gingivitis. 

 

2. Antioxidant Effects 

A large number of studies have shown that oxidative 

stress is caused by the imbalance between the excessive 

production of reactive oxygen species (ROS) and the 

relative lack of antioxidants, and oxidative stress is also 

one of the pathophysiological mechanisms of periodontal 

tissue inflammation [13]. ROS can change the periodontal 

microenvironment by activating inflammatory factors, 

nuclear factor KB (NF-KB), c-Jun amino terminal kinases 

(JNKs) and autophagy, causing indirect serious damage to 

periodontal tissue, leading to periodontitis [14]. Some 

people measured the antioxidant activity of agarwood 

essential oil by 1,1-diphenyl-2-trinitrophenylhydrazine 

(DPPH) radical scavenging and iron ion reduction / 

antioxidant capacity method (FRAP), proving that it has a 

good antioxidant capacity in vitro [15]. Its essential oil 

extract β- Caryophyllene shows strong antioxidant effect 

[16]. Its antioxidation can reduce the level of intracellular 

reactive oxygen species to a certain extent, and 

significantly enhance the cellular antioxidation. The 

activity of enzyme SOD and GSH Px can protect PC12 

cells from oxidative damage induced by H2O2 [17]. There 

is also a flavonoid compound in the agarwood extract that 

can provide antioxidant effect by preventing the formation 

of ROS, directly capturing ROS, protecting lipophilic 

antioxidants and stimulating the increase of enzymatic 

antioxidants [18]. In addition, different concentrations of 

agarwood essential oil have scavenging effects on DPPH 

free radicals, hydroxyl free radicals and superoxide anion 

free radicals, and with the increase of the concentration of 

agarwood essential oil, the antioxidant capacity gradually 

increases, with obvious correlation [19]. The analysis 

results also showed that both young leaves and mature 

leaves of agarwood have strong antioxidant activity, and 

the two kinds of leaves have the same use value in terms 

of chemical content and antioxidant capacity, which can 

reduce inflammatory reaction to a certain extent [20]. 

Agarwood essential oil shows certain antioxidant capacity 

in various systems, can reverse the imbalance between 

reactive oxygen species and antioxidants, and has the 

potential to be applied to gingivitis. Therefore, agarwood 

is a natural antioxidant, which can resist oxidative stress 

and alleviate gingivitis. 

 

3. Antibacterial Activity 

The antibacterial and anti-inflammatory effects of 

agarwood are the main mechanisms to alleviate 

gingivitis. Gingivitis is caused by substances 

accumulated in or near the gingival sulcus by microbial 

plaque. Dental plaque is the main cause related to the 

development of gingivitis. It can aggravate inflammatory 

reaction by enhancing plaque accumulation or enhancing 

the susceptibility of gingival tissue to microbial attack. 

In recent years, it has been reported that agarwood has 

antibacterial activity and can inhibit some bacteria in oral 

cavity. Bacteria in the mouth mainly include 

Streptococcus mutans, Porphyromonas gingivalis, 

Staphylococcus, etc. The antibacterial activity test 

shows that agarwood essential oil has a good inhibitory 

effect on Gram-negative bacteria and Gram-positive 

bacteria, and has a more obvious antibacterial effect on 

Gram-positive bacteria. Because the cell wall of the 

external gram-negative bacteria contains a layer of 

lipopolysaccharide, which prevents hydrophobic 

compounds from entering the cells, thereby reducing the 

bacteriostatic effect [21]. In the process of agarwood 

formation, the infection of pathogenic bacteria causes the 

defense system of the Aquilaria Sinensis to resist 

external damage. It can prevent further infection of the 

pathogenic bacteria by generating local allergic reaction, 

that is, blocking the damage site [22]. This indicates that 

antibacterial activity has been carried out in the 

process ofagarwood formation, so agarwood itself may 

have antibacterial activity. In previous studies, Mei 

showed that Chinese agarwood essential oil has anti 

MRSA activity [23]. Wetwitayaklung found that 

agarwood essential oil (A. crassna) has antibacterial 

activity against Candida albicans [24]. Filter paper 

method was used to test the antibacterial ability of 

agarwood essential oil by measuring the antibacterial 

circle. With the increase of the concentration of 

agarwood essential oil, the inhibition rate against 

bacteria increased. The inhibition rate of agarwood 

essential oil against bacteria is in the following order: 

Staphylococcus aureus > Bacillus subtilis > Escherichia 

coli [25]. The antibacterial effect of agarwood essential 

oil is related to sesquiterpenes and chromones in 

agarwood. Sesquiterpenes usually have antibacterial 

activity. Studies have found that sesquiterpenes in the 

volatile oil of agarwood β- Caryophyllene has significant 

antioxidant and antibacterial properties. Its antibacterial 

activity is attributed to its strong antioxidant activity 

[26]. Flavone widely exist in the plant kingdom, and are 

one of the main components of agarwood. The 

pharmacological activities of flavonoids include anti-

inflammatory activity, anti allergic activity, antioxidant 

activity, anti-tumor activity, antifungal and antibacterial 

activity, which can inhibit a variety of bacterial virulence 

factors [27]. 

 

4. Analgesic and Sedative Effects 

Most plant herbs have antipyretic and analgesic effects. 

The analgesic and sedative effects of agarwood can 

alleviate the clinical manifestations of gingivitis, such as 

swelling and pain. The agarwood contains a variety of 

analgesic and sedative substances, and valerenic acid has 

obvious sedative activity, α- Sandalyl alcohol and 

agarospirol have the same chlorpromazine like stabilizing 

effect as agallospirol. Through animal experiments, 

researchers found that agarwood oil has a sedative effect on 



ISSN : 2693 6356 

2022 | Vol 5 | Issue 2 

 
mice, which is manifested in that the autonomous motor 

activity of mice inhaled agarwood oil gradually decreases 

with the increase of medication time [28]. In addition, some 

scholars evaluated the pharmacodynamic effects of 

different parts of agarwood on sedation and hypnosis 

through the hypnosis experiment with pentobarbital 

sodium and the autonomous activity experiment. They 

found that the volatile oil of agarwood could significantly 

prolong the sleep time and increase the proportion of mice 

entering sleep. Based on the experimental results, the 

active molecules with sedative and hypnotic effects in the 

volatile oil of agarwood were further inferred [29]. In 

addition, they evaluated the sedative and hypnotic effects 

of agarwood essential oil through animal behavior 

experiments and explored the potential mechanism of 

action on GABA ergic system. The results showed that 

agarwood volatile oil has a versatile sedative and hypnotic 

effect, and its mechanism of action may be related to 

regulating the gene expression of GABAA receptor, 

enhancing the function of GABAA receptor, and 

promoting the influx of CL
-1

 [30]. Researches have 

compared  the analgesic effects of different years 

ofagallodendron, and deduce that the volatile oil of 

agallodendron can significantly increase the pain threshold 

of mice and reduce the number of writhing induced by acetic 

acid in mice, proving that it has a clear analgesic effect 

[31]. The nonsteroidal anti-inflammatory drug diclofenac 

is a commonly used anti-inflammatory drug with analgesic 

and anti-inflammatory effects. The anti-inflammatory 

activity of agarwood essential oil in vivo and in vitro is 

comparable to that of standard diclofenac [9]. The 

analgesic and sedative effects of agarwood essential oil can 

be applied to gingivitis to alleviate the pain reaction caused 

by gingivitis and the active inflammation and immune 

reaction in the gums. 

 

5. Immune Activity of Agarwood 

The development of gingivitis is mostly due to the 

chronic inflammatory process caused by long-term 

microbial stimulation of the gums. Gingivitis involves a 

series of immune reactions, such as the accumulation of 

lymphocytes, macrophages and plasma cells in the place 

where   inflammation occurs. Overinduction, 

prolongation or imbalance of immune response will lead 

to immune diseases. Gingivitis is also an immune 

disease. Agarwood is not only able to enhance the 

cellular and humoral immune functions of the body, but 

also inhibit the immune function and reduce the release 

of inflammatory factors. This two-way immune 

regulation reflects the theory of "holism" and "balance 

between yin and yang" emphasized by traditional 

Chinese medicine [32]. Through modern 

pharmacological research, it has been found that 

agarwood and its essential oil have a variety of 

pharmacological activities, which may be related to their 

strong immune regulatory function. Inflammation, as the 

most basic immune reaction of the body, makes it 

possible to find new anti-inflammatory drugs from 

agarwood essential oil. Because of the correlation 

between immune reaction and inflammation, it was 

isolated from agarwood. Tryptone and sesquiterpene are 

not only the main anti-inflammatory substances, but also 

the main immunoactive substances. Compound CYF-2 is 

an epoxide 2 - (2-phenylethyl) - chromone derivative 

isolated from agarwood, which can significantly inhibit 

the activation of microglia, dendritic cells and 

neutrophils, which play an important role in innate 

immunity. In addition, GYF-21 significantly inhibits the 

transformation of adaptive immune+T cells into helper 

T cell 1 (Th1) and helper T cell 17 (Th17) by inhibiting 

the differentiation of primitive CD4, and inhibits the 

activation, proliferation and IFN of CD8- γ Secreting+t 

cells. Mechanism study showed that GYF-21 

significantly inhibited STAT1/3 and NF in microglia- κ 

Activation of B signal path. In conclusion, GYF-21 can 

inhibit STAT1/3 and NF- κ B signal pathway 

significantly inhibits innate immunity and acquired 

immunity [7]. In addition, compound HHX-5 is a 

sesquiterpene derivative from agarwood. HHX-5 

significantly inhibits the activation of macrophages and 

neutrophils, which plays an important role in innate 

immunity. In addition, HHX-5 strongly 

inhibits the transformation of adaptive immune +t cells 

into Th1, Th2 and Th17 cells by inhibiting the 

differentiation of original CD4, and inhibits the activation, 

proliferation and differentiation of CD8+t cells and B 

cells. Inhibits innate and adaptive immunity by inhibiting 

STAT signaling pathway [33]. The excesive immunity of 

macrophages and neutrophils in inflammatory reaction is 

the main immune mechanism that causes gingivitis. 

Because the chromone and sesquiterpene in agarwood 

can inhibit the relevant signal pathway and immune 

response respectively, in conclusion, agarwood has the 

possibility to alleviate the overimmunity of gingivitis. 

 

6. Conclusion 

Sesquiterpenoids, flavonoids, quercetin, and 
other chemicals make up Agaricus formosana, 

the active ingredient in traditional Chinese 

medicine. There are a number of 

pharmacological effects shown by the active 

components of agarwood, including anti-

inflammatory, antioxidant, bacteriostatic, 

analgesic, sedative, and immunological 

properties. Plaque buildup on the gingival edge 

causes gingivitis, a persistent inflammatory 

condition. Finding a medication that can reduce 

inflammation without causing too many negative 

effects is a key area of focus in gingivitis 

research. In comparison to manufactured 

chemical medications, agarwood is safer. 

Nevertheless, agarwood is seldom used to treat 

gingivitis. By providing evidence of the 

aforementioned benefits, this study elucidates a 

potential mechanism by which agarwood reduces 

inflammation in periodontal tissues. For the 

agarwood industry to undergo a revolution, it 

offers a theoretical foundation. 



References 

[1] [1] In an article published in 2008 in the Journal 
of Ethnopharmacology, the authors Zhou, Wang, 
Suolangjiba, and others investigated the anti-
inflammatory and antinociceptive effects of an 
extract from the leaves of Aquilaria sinensis 
(Lour.) Gilg.  
Four Novel 2-(2-Phenylethyl) chromone 
Derivatives from Chinese Agarwood Derived via 
the Whole-Tree Agarwood-Inducing Method [2] 
Liu Y, Chen D, Wei J, et al. Published in 2016 in 
volume 21, issue 11, this article is referenced as 
1433. 
the thirdThe authors of the article are Wang SL, 
Hwang TL, Chung MI, and others. Emerging 
Flavones, 
Anti-Inflammatory Components and a 2-(2-
Phenylethyl)-4H-chromen-4-one Derivative 
Derived from Aquilaria sinica Stem Barks. The 
citation is from the journal Molecules, volume 
20, issue 11, pages 20912–20925, published in 
2015.  
Citation: [4] Liu Y, Chen H, Yang Y,... Aquilaria 
sinensis trees can be efficiently and innovatively 
produced high-quality agarwood using the 
whole-tree agarwood-inducing technology. 
Chemical Communications. 2013; 18(3): 3086-
3106.  
This comes from the work of Shao H, Mei WL, 
Kong FD, and others [5]. Chinese agarwood "Qi-
Nan" obtained from Aquilaria sinensis contains a 
novel 2-(2-phenylethyl) chromone glycoside. 
Journal of Asian Natural Product Research, 
2017, 19, 1, 42–46.  
Agarwood alcohol extract inhibits oxidation and 
inflammation, protecting against gastric ulcers 
[6] (Wang C, Peng D, Liu Y, et al.). Review of 
Alternative and Complementary Medicine, 2021, 
2021: 9944685.  
According to Guo R, Zhao YF, Li J, and others, 
GYF-21, a derivative of the epoxide 2-(2-
phenethyl)-chromone, inhibits the STAT1/3 and 
NF-κB signaling pathways, hence suppressing 
innate and adaptive immunity. Published in 2017 
in the journal Front Pharmacol, volume 8, page 
281.  
[8] Agarwood tea, a new modern herbal beverage 
made from the leaves of the Aquilaria 
(Thymelaeaceae) plant, and its pharmacological 
characteristics. Research by Adam AZ, Lee SY, 
and Mohamed R. Article published in 2017 in the 
Journal of Herbal Medicine, volume 10, pages 
37–44.  
9. Yadav DK, Mudgal V, Agrawal J, et al. 
Topical anti-inflammatory effectiveness of 
natural components of Agarwood oil studied by 
molecular docking and adverse drug event 
(ADEE) investigations. The current state of 
computer-assisted drug design is 360–370.  
Three novel sesquiterpenoids and one novel 
sesquiterpenoid derivative were isolated from 
Chinese eaglewood by Zhao, Peng, Han, and 
colleagues [10]. Chemicals. 2016; 21(3): 281.  

A study was conducted by Ma CT, Ly TL, Le 
THV, and colleagues on the anti-inflammatory 
effects of sesquiterpene derivatives derived from 
Aquilaria malaccensis agarwood on NO 
generation by macrophage RAW 264.7 cells 
[11]. Journal of Phytochemistry, 2021, 183: 
112630.  
Inhibition of p-STAT3 and IL-1 β/IL-6 is the 
mechanism by which the essential oil of Chinese 
agarwood has an anti-inflammatory effect (Gao 
XL, et al., 2012). The article is published in the 
Chinese Pharmaceutical Journal in 2019 and has 
the DOI: 54/23/51-1957.  
This information is sourced from the work of R 
G Kumar L, Chatterjee NS, Tejpal CS, and 
others. Optimal chitosan wall material for spray-
dried microencapsulation of squalene: oxidative 
stability experiments and characterization. 
Worldwide Journal of Biomolecular Science, 
2017, 104 (Part B): 1986-1995.  
According to [14] Chen, Cai, Zhao, et al. A 
meta-analysis and comprehensive review of 
biomarkers in saliva and gingival crevicular fluid 
linked to oxidative stress and chronic 
periodontitis. Journal of Clinical Periodontics. 
2019; 46(6): 608-622.  
A study conducted by Waddington, Moseley, and 
Embery [15] was conducted. Theories Behind 
Periodontal Disease: One possible component of 
periodontal disease pathophysiology is reactive 
oxygen species. Journal of oral disorders, 2000, 
6, 3, 138–151.  
[16] GC-MS by Wang, Li, Luo, and colleagues 
An analysis of the chemical constituents of 
agarwood and several Aquilaria sinensis (Lour.) 
Gilgorgans from various Asian nations. The 
article is published in Molecules on April 23, 
2018, volume 23, issue 9, pages 2168.  
[17] In a study conducted by Dahham, Tabana, 
and Iqbal et al. The antibacterial, anticancer, and 
antioxidant characteristics of the sesquiterpene β-
caryophyllene derived from the Aquilaria crassna 
essential oil. Citation: Molecules, 2015, 20(7): 
11808-11829.  
 
The essential oil of Lignum Aquilariae 
Resinatum protects PC12 cells from oxidative 
damage caused by hydrogen peroxide, according 
to Xiong LY et al. [18]. Chinese Journal of 
Pharmaceutical Research, Volume 25, Issue 1, 
Pages 28–32, 2014.  
By Parwata, Manuaba, and Yasa [19] we mean... 
Gyrinops versteegii leaves, an extract of which is 
water-based, contain powerful flavonoid 
components that function as antioxidants. Journal 
of Biomedical and Pharmacology, 2018, 11(3): 
1501-1511.  
According to Ma, Qiao, Fu, et al. (2021). The 
Biological Activity of Man-Made and Naturally 
Occurring Agarwood: A Comparative Study. 
Article number: 1532 in Forests, volume 12, 
issue 11.  
Reference: [21] Batubara R, Wirjosentono B, 
Siregar AH, and colleagues. Antimicrobial action 



ISSN : 2693 6356 

2022 | Vol 5 | Issue 2 

 
against skin-dwelling bacteria and fungus, as 
well as bioactive components of an ethanol 
extract of agarwood leaves (Aquilaria 
malaccensis). Publication: Biodiversitas, Volume 
22, Issue 1, Pages 2884–2890, 2021.  
Mikaido H. [22] Bacterial cell wall permeability. 
"Angew Chem International, English Edition," 
1979, 18, 5, 337–350.  
Proteinase inhibitor gene families: methods for 
enhancing herbivore resistance via genetic 
engineering [23] Ryan CA. Volume 10, Issue 1, 
pages 20–24, 1989, Bioessays.  
[24] Huang Y, Wu J, Zeng Y, et al. The chemical 
make-up and anti-MRSA efficacy of Chinese 
eaglewood essential oil. The citation is from the 
Journal of Chinese Pharmaceutical Science, 
volume 17, issue 3, page 225.  
Essential oil and heartwood extracts of Aquilaria 
crassna produced by water distillation and 
supercritical fluid carbon dioxide extraction: 
chemical components and antibacterial activity 
[25] Wetwitayaklung P, Thavanapong N, 
Charoenteeraboon J. Volume 2009, Issue 3, 
Pages 25–33, Journal of Science, Technology, 
Engineering, and Health Affairs.  
 
Cushnie and Lamb [26] said. A better knowledge 
of flavonoids' antimicrobial activities has 
recently emerged. Journal of antimicrobial 
agents: an international publication, 2011, 38 (2), 
99-107.  
This sentence is paraphrased from a publication 
by Takemoto et al. [27]. Exploring the sedative 
effects of vaporizing spikenard extract and 
agarwood oil, as well as identifying their active 
ingredients. ―Journal of the National Medical 
Association‖ (2008), 62(1), 41–46.  
Wang S. et al. [28] investigated the effects of 
agarwood made using the whole-tree agarwood-
inducing approach on the suppression of 
spontaneous activity and hypnosis in mice. 
Published in the Journal of International 
Pharmaceutical Research in 2016, volume 43, 
pages 1082–1089.  
An Essential Oil from Agarwood Demonstrates 
GABAergic-Mediated Sedative-Hypnotic Effects 
[29] Wang et al. "Molecules" published in 2017 
with the DOI 22/12: 2190.  
[30] Research by Wang et al. comparing the 
analgesic effects of Chinese eaglewood from 
various years. (Hainan Medical Journal, 2014, 
25: 2188-2190).  
The article "Aquilaria Species (Thymelaeaceae) 
Distribution, Volatile and Non-Volatile 
Phytochemicals, Pharmacological Uses, 
Agarwood Grading System, and Induction 
Methods" was written by Wang Y, Hussain M, 
Jiang Z, and others—[31]. Journal of Molecules, 
2021, 26, 24: 7708.  
The authors of the piece are Ma HD, Deng YR, 
Tian Z, and Lian ZX. The relationship between 

TCM and immunological modulation. Clinical 
Review of Allergy and Immunology. 2013; 
44(3): 229–241.  
According to research by Zhu, Zhao, Huo, and 
colleagues, HHX-5, a sesquiterpene derivative 
found in Chinese agarwood, inhibits STAT 
signaling pathways and hence reduces both 
innate and adaptive immunity [33]. European 
Journal of Pharmacology, 2016, 791: 412-423. 


