Phytochemistry and Pharmacology of Sesquiterpenoids from Atractylodes DC. Genus Rhizomes

The rhizomes of the genus Atractylodes DC. consist of various bioactive components, including sesquiterpenes, which have attracted a great deal of research interest in recent years. In the present study, we reviewed the previously published literatures prior to November 2023 on the chemical structures, biosynthetic pathways, and pharmacological activities of the sesquiterpenoids from this genus via online databases such as Web of Science, Google Scholar, and ScienceDirect. Phytochemical studies have led to the identification of more than 160 sesquiterpenes, notably eudesmane-type sesquiterpenes. Many pharmacological activities have been demonstrated, particularly anticancer, anti-inflammatory, and antibacterial and antiviral activities. This review presents updated, comprehensive and categorized information on the phytochemistry and pharmacology of sesquiterpenes in Atractylodes DC., with the aim of offering guidance for the future exploitation and utilization of active ingredients in this genus.

The rhizomes of the Atractylodes DC. genus are rich in essential oils, which have been traditionally used for the treatment of gastrointestinal, coronavirus, and rheumatic diseases in China, Korea, and Japan [3][4][5][6].The rhizomes of A. lancea have been used as crude drugs in the Chinese and Japanese pharmacopoeia, which are referred to Cangzhu and Sojutsu, respectively [7,8].In addition, A. lancea (known as Khod-Kha-Mao in Thailand) is also used for the treatment of fevers and colds in Thai traditional medicine [9]. A. macrocephala is not only used as functional food in China but has also been historically widely used in traditional Korean and Japanese medicine [10].These traditional uses of Atractylodes DC. are closely related to its intrinsic chemical composition [11,12].
Sesquiterpenes are significant oily compositions with extensive dispersal in plants, currently gaining recognition due to their wide range of pharmacological effects, including antitumor, anti-inflammatory, antibacterial and antiviral, etc. [13][14][15].According to the diverse skeletal structures of sesquiterpenes in Atractylodes DC., they can be divided into the following five categories: eudesmane-type (such as β-eudesmol, atractylon), guaianetype (such as atractylmacrol A, atrchiterpene D), spirovetivane-type (such as hinesol, hinesolone), isopterocarpolone-type (such as 14-hydroxy-isopterocarpolone, Atractyloside I), and eremophilane-type [10,[16][17][18][19][20][21].β-eudesmol, atractylon, and hinesol are usually used as chemical markers for evaluating the quality of Atractylodes DC. in different regions [22][23][24][25].Many studies have been conducted on Atractylodes DC. [26,27], yet there are still noticeable deficiencies in the literature.Various potential clinical uses and upcoming research paths have been suggested, offering a comprehensive collection of research discoveries on the sesquiterpenes of Atractylodes DC.Hence, the current work presents the chemical constituents, possible biosynthesis, and pharmacologic mechanisms of sesquiterpenoids from Atractylodes DC. genus rhizomes in order to encourage researchers to explore this genus in depth with the aim of discovering novel bioactive substances.

Methodology
This present review article considered the previously published literature prior to November 2023 concerning the chemical components, biosynthetic pathways, and pharmacological activities of sesquiterpenoids from the genus Atractylodes DC.The search was conducted using online databases such as Web of Science, Google Scholar, ScienceDirect, PubMed, CNKI, Baidu Scholar, and classic books on Dictionary of TCM.The key words searched included Atractylodes DC., Asteraceae, secondary metabolites, phytochemistry, sesquiterpenoids, biosynthetic, atractylenolides, biological activity, pharmacological, and the names of each species of the genus.The chemical structures were drawn using Chem-Draw Professional 14.0 software.

Phytochemical Constituents
Our literature investigation revealed that essential oils are the main active ingredient in the genus Atractylodes, among which sesquiterpenoids are the characteristic components.Currently, 163 sesquiterpenoids have been isolated and identified from the genus Atractylodes DC., including 104 eudesmane-type, 32 guaiane-type, 14 spirovetivane-type, 11 isopterocarpolone-type, and 2 eremophilane-type sesquiterpenoids.Their specific chemical names, structures, sources, collection areas, and year of isolation are shown in Tables 1-5.

Biosynthesis of Sesquiterpenes
Farnesyl pyrophosphate (FPP) has been recognized as a sesquiterpenoid biosynthetic precursor and generates diverse sesquiterpene carbon skeletons via irregular coupling reactions [75,76].FPP undergoes one cyclization or more to form germacryl cations, which lose a proton to produce the intermediate germacrenes A/B, followed by a series of protonation, structural rearrangements, and substitutions of various hydroxyls via oxidation reactions to produce eudesmane, guaiane, spirovetivane, isopterocarpolone, and eremophilane skeletons [77][78][79].The possible biosynthetic pathways of various sesquiterpene types are shown in Figure 1.   A. lancea [57] China (Huanggang city, Hubei province) 2016

Biosynthesis of Sesquiterpenes
Farnesyl pyrophosphate (FPP) has been recognized as a sesquiterpenoid biosynthetic precursor and generates diverse sesquiterpene carbon skeletons via irregular coupling reactions [75,76].FPP undergoes one cyclization or more to form germacryl cations, which lose a proton to produce the intermediate germacrenes A/B, followed by a series of protonation, structural rearrangements, and substitutions of various hydroxyls via oxidation reactions to produce eudesmane, guaiane, spirovetivane, isopterocarpolone, and eremophilane skeletons [77][78][79].The possible biosynthetic pathways of various sesquiterpene types are shown in Figure 1. A. lancea [57] China (Huanggang city, Hubei province) 2016

Biosynthesis of Sesquiterpenes
Farnesyl pyrophosphate (FPP) has been recognized as a sesquiterpenoid biosynthetic precursor and generates diverse sesquiterpene carbon skeletons via irregular coupling reactions [75,76].FPP undergoes one cyclization or more to form germacryl cations, which lose a proton to produce the intermediate germacrenes A/B, followed by a series of protonation, structural rearrangements, and substitutions of various hydroxyls via oxidation reactions to produce eudesmane, guaiane, spirovetivane, isopterocarpolone, and eremophilane skeletons [77][78][79].The possible biosynthetic pathways of various sesquiterpene types are shown in Figure 1.  A. lancea [57] China (Huanggang city, Hubei province) 2016

Biosynthesis of Sesquiterpenes
Farnesyl pyrophosphate (FPP) has been recognized as a sesquiterpenoid biosynthetic precursor and generates diverse sesquiterpene carbon skeletons via irregular coupling reactions [75,76].FPP undergoes one cyclization or more to form germacryl cations, which lose a proton to produce the intermediate germacrenes A/B, followed by a series of protonation, structural rearrangements, and substitutions of various hydroxyls via oxidation reactions to produce eudesmane, guaiane, spirovetivane, isopterocarpolone, and eremophilane skeletons [77][78][79].The possible biosynthetic pathways of various sesquiterpene types are shown in Figure 1.

Pharmacological Activities
Pharmacological studies have shown that the majority of Atractylodes DC. species exhibit anticancer, anti-inflammatory, antibacterial and antiviral, antioxidant, neuroprotective, and gastrointestinal protection properties.The bioactivities and the corresponding pharmacological mechanisms of the crude extract and isolated sesquiterpenes are listed in Table 6.These findings support the traditional use of Atractylodes DC. in terms of pharmacological activity.

Anticancer Activity
Mao et al. [80] determined that an appropriate concentration of atractylon can inhibit the proliferation and promote the apoptosis of intestinal cancer cells by suppressing the PI3K/AKT/mTOR signaling pathway.In addition, atractylon regulates the expression of thymopoietin antisense transcript 1 (TMPO-AS1) and coiled-coil domain-containing 183 antisense RNA 1 (CCDC183-AS1) and inhibits the invasion and migration of liver cancer cells [81].β-eudesmol was found to have moderate activity against human cholangiocarcinoma (HuCCT-1) cell growth with an IC 50 (concentration that inhibits cell growth by 50%) value of 16.80 ± 4.41 µg/mL through the Notch signaling pathway and its upstream/downstream molecules in the CCA cell line at the gene and protein expression levels [82].Moreover, β-eudesmol treatment (2.5-5 mg/kg) significantly inhibited the growth of H 22 and S 180 mouse tumor in vivo, which indicated that it inhibited angiogenesis via suppressing CREB activation in growth factor signaling pathway [83].Hinesol can induces the apoptosis of human leukemia-60 (HL-60) cells through the JNK signaling pathway in HL-60 cells [70].Furthermore, hinesol reduced cell proliferation via the arresting cell cycle at the G1 phase and induced apoptosis.Further experiments revealed that hinesol inhibited the phosphorylation of MEK and extracellular signal-regulated kinase (ERK) and downregulated the expressions of NF-κB p65 and phosphor-p65 in nuclei [84].Atramacronoid A induced SGC-7901 cells apoptosis through the promotion of the synthesis of neutrophil elastase [44].AT-I, AT-II, and atractylon showed the most potent antitumor activity against B16 cells, and they could also induce cell differentiation and inhibit cell migration through inactivating Ras/ERK MAPK (for AT-I and AT-II) and PI3/AKT pathways [85].AT-I can downregulate the expression of cyclin-dependent kinases (CDK1) in ovarian cancer SK-OV-3 and ovarian carcinoma (OVCAR)-3 cells through the PI3K/AKT pathway, which leads to cell cycle arrest in the G2/M phase, and plays an important role in the proliferation inhibition of tumor cells [86].AT-I inhibited the self-renewal capacity of gastric stem-like cells (GCSLCs) via the suppression of their sphere formation capacity and cell viability.AT-I attenuated gastric cancer stem cell (GCSC) traits partly through inactivating Notch1, leading to a reduction in the expressions of its downstream targets Hes1, Hey1, and CD44 in vitro [87].AT-I showed significant antitumor activity on A549 and HCC827 cells in vitro and in vivo, and the possible mechanism of action may be related to apoptosis induced by AT-I via a mitochondria-mediated apoptosis pathway [88].Ye et al. [89] demonstrated that the G1-arresting and apoptotic effects of AT-II in B16 cells involve p38 activation as well as ERK and Akt inactivation, and the cytotoxic/apoptotic effects of AT-II are potentially p53-dependent.AT-II exerted significant antitumor effects on gastric carcinoma cells by modulating the Akt/ERK signaling pathway, which upregulated the expression level of Bax but downregulated the expression levels of B-cell lymphoma-2 (Bcl-2), p-Akt, and p-ERK compared to those of the control group [90].Codonolactone, also named AT-III, which inhibited the programming of the epithelial-mesenchymal transition (EMT) in vitro and in vivo, inhibited the motility of metastatic breast cancer cells through the downregulation of transforming growth factor (TGF)-β signaling, and blocked the activation of Runx2 phosphorylation [91].AT-III can induce the apoptosis of lung carcinoma cells via inhibiting cell growth, increasing lactate dehydrogenase release, and modulating the cell cycle in human lung carcinoma A549 cells.In addition, it also inhibited the proliferation and capillary tube formation of human umbilical vein endothelial cells [92].

Anti-Inflammatory Activity
Lipopolysaccharides (LPS) act as prototypical endotoxins, inducing inflammation, septic shock, and death, and are commonly used for in vitro models of inflammation [143].Nitric oxide (NO) is one of the inflammatory mediators of many organs; inhibitors of NO production may have therapeutic potential in the treatment of inflammation accompanying the overproduction of NO [144].It was determined that the existing cyclic ether on the skeleton of sesquiterpenes is responsible for protective activity against neuroinflammation in LPS-induced BV-2 microglia [45].AT-I displayed a potent inhibitory effect on angiogenesis through the downregulation of NO, tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-6, VEGF, and PlGF in chronic inflammation [93].Jin et al. [94] reported that AT-I inhibited the LPS-induced phosphorylation of p38 and ERK mitogen-activated protein kinases (MAPKs) and showed anti-inflammatory activity in RAW264.7 cells.AT-I also inhibited the proliferation of vascular smooth muscle cells (VSMCs) induced by oxidized modified low-density lipoprotein (OXLDL).Migration contributes to antiatherosclerosis by responding to the expression of monocyte chemoattractant protein-1 (MCP-1) and by downregulating the expression of effective inflammatory mediators of the vascular inflammatory response [95].AT-I extracted from A. macrocephala rhizomes effectively inhibited the increase in vascular permeability in mice caused by acetic acid and reduced cotton pellet granuloma tissue proliferation significantly, which proved that it was an active compound in acute and chronic inflammation models in mice [96].AT-I was reported previously to act on white blood cell membranes and TLR 4 , and its anti-inflammatory activity is related to antagonizing the TLR 4 pathway [97].AT-I shows an anti-inflammatory effect by inhibiting TNF-α and IL-6 production.The anti-inflammatory molecular mechanism of AT-I may be associated with the inhibition of the NF-κB, ERK 1/2, and p38 signaling pathways [98].Animal studies further demonstrated that AT-I and AT-III exert their anti-inflammatory effects by downregulating lipopolysaccharide (LPS)-induced TNF-α expression and inducible NOS (iNOS) expression.Meanwhile, AT-I showed more potent inhibition than AT-III in the production of TNF-α and NO in LPS-activated peritoneal macrophages [99].Moreover, in vivo experiments revealed that AT-III could alleviate osteoarthritis by inhibiting chondrocyte senescence through reduced phosphorylation of IκB kinase (IKK) α/β, IκBα, and P65 in the NF-κB pathway [100].Li et al. [101] discovered that atractylon significantly inhibited the ERK, JNK, and NF-κB expression induced by LPS in BV2 cells.It is suggested that atractylone is able to alleviate LPS-induced inflammatory responses through the downregulation of the ERK, JNK, and NF-κB pathways in BV2 cells.Atractylon significantly inhibited NO and prostaglandin E 2 production, as well as inducible NO synthase and cyclooxygenase-2 expression in LPS-induced RAW 264.7 cells.Atractylon also significantly reduced the acetic acid-induced writhing response, carrageenan-induced pawedema, and hot-plate latent pain response [35].Seo et al. [102] investigated the regulatory mechanism of β-eudesmol on mast cell-mediated inflammatory response; the results indicated that it inhibited the production and expression of IL-6 on phorbol 12-myristate 13-acetate and calcium ionophore A23187-stimulated human mast cells (HMCs) via suppressing the ac-tivation of p38 MAPKs and NF-κB in activated HMC-1 cells, as well as the activation of caspase-1 and expression of receptor-interacting protein-2.

Antimicrobial and Antiviral Activity
Previous studies have proven that the spatial arrangement of the terpenoid skeleton combined with an α-methylene-γ-lactone moiety exhibits obvious antiviral activity [145].Atractyloside A not only possesses anti-influenza B virus infection effects in vivo and in vitro but also can regulate macrophage polarization to the M2-type, which can effectively attenuate the damage caused by influenza B virus infection [103].Shi et al. [104] reports that atractylon has anti-influenza virus A H3N2, anti-influenza virus A H5N1 (avian influenza virus), and anti-influenza B virus effects at non-toxic concentrations.Cheng et al. [105] determined that atractylon significantly alleviated influenza A virus (IAV)-induced lung injury via regulating the Toll-like receptor 7 (TLR-7) signaling pathway and may warrant further evaluation as a possible agent for IAV treatment.The essential oil of A. lancea exhibited antibacterial activities against both Gram-positive and Gram-negative bacteria through the simultaneous disruption of the cell membrane [106].The administration of A. macrocephala ethanol extracts (5-40 mg/mL) for 24 h remarkably inhibited the growth of Staphylococcus aureus, Escherichia coli, Bacillus subtilis, and Shigella felxneri bacteria.Meanwhile, the ethanol extracts from the above-ground portion of the plant showed greater antibacterial activity than extracts of rhizome tissues [107].Li et al. [108] demonstrated that the essential oil of A. lancea had antimicrobial activity against clinical isolates of multidrug-resistant Escherichia coli.Wan et al. [109] discovered that atractylodes essential oil showed antifungal activity against Colletotrichum karstii, Colletotrichum gloeosporioides, Colletotrichum camelliae, Colletotrichum fioriniae, and Colletotrichum chongqingense with EC 50 values of 0.089, 0.165, 0.108, 0.205, and 0.092 mg/mL, respectively, and had a significantly higher antifungal effect in the contact phase than that in the vapor phase (p < 0.05).

Insecticidal Activity
Sesquiterpenoids are well known as major constituents of essential oils and play important ecological roles in the plants' interactions with pollinators and predators to adapt to the environment [146].In previous reports, atractylon and β-eudesmol were toxic to fruit flies (LD 50 = 1.63 and 2.65 µg/adult, respectively), while the crude oil of A. lancea had an LD 50 value of 2.44 µg/adult [49].β-eudesmol exhibited contact toxicity and ovicidal activity against Plutella xylostella diamondback moths [110].Although hinesol and β-eudesmol expressed some repellent and contact toxicities against Tribolium castaneum adults (red flour beetles), they displayed a lower repellency level (p < 0.05) than those of N,N-Diethyl-3-methyl benzoyl amide (DEET), and their contact toxicity of them was unremarkable [111].AT-III and atractylon were proven to possess contact and fumigant toxicities against Dermatophagoides farinae and Dermatophagoides pteronyssinus house dust mite adults using fabric-circle residual contact and vapor-phase toxicity bioassays.They were much more toxic toward house dust mite adults (D. farinae and D. pteronyssinus) than either DEET or dibutyl phthalate but slightly less active than benzyl benzoate [112].He et al. [113] determined that the hexane-soluble phase of A. lancea has high lavicidal activity against Culex pipiens pallens Coquillett, wild Culex pipiens molestus Forskal, and Aedes albopictus Skuse, which have the potential to be developed as a novel insecticide.

Neuroprotective Activity
To date, sesquiterpene lactones from medicinal plants have been reported to exhibit a neuroprotective effect against glutamate-induced neurotoxicity in cultured neurons [147].Biatractylenolide exerted a neuroprotective effect against glutamate-induced excitotoxicity via decreasing the formation of reactive oxygen species (ROS) and the activity of acetylcholinesterase (AChE) and increasing the expression of synapsin I and protein kinase C (PKC) in D-galactose-treated mice, which may have therapeutic potential in aging-related memory impairment [114].In PC12 and SH-SY5Y cells, biatractylolide could modulate PI3K-Akt-GSK3β-dependent pathways to protect against glutamate-induced cell damage [115].AT-III was shown to be able to protect phaeochromocytoma (PC) 12 cells from corticosterone-induced injury by inhibiting intracellular Ca 2+ overloading and the mitochondrial apoptotic pathway, as well as modulating the MAPK/NF-κB inflammatory pathways, which may serve as a therapeutic agent in the treatment of depression [116].Liu et al. [117] determined that AT-III exhibited a significant neuroprotective effect against glutamate-induced neuronal apoptosis via inhibiting the caspase signaling pathway, which markedly attenuated the caspases-3-like activity and may therefore have therapeutic potential in excitotoxicity-mediated neurological diseases.In a chronic unpredictable mild stress (CUMS) mouse model, AT-I (5-20 mg/kg) increased sucrose preference and shortened the immobility time in the forced swimming and tail suspension tests and reduced CUMS-induced decreases in serotonin and norepinephrine in the hippocampus [118].Zhou et al. [119] found that AT-III produces antidepressant-and anxiolytic-like effects, which are related to the normalization of proinflammatory cytokine levels under chronic mild stress.AT-II may reduce the injury of neuronal HT22 cells by oxidative stress through phosphatidylinositol-3 kinase/protein kinase B [120].In a Parkinson's disease model, AT-I, AT-II, biepiasterolid, isoatractylenolide I, and AT-III showed a significant protective effect on MPP + -induced SH-SY5Y cells at 1-10 µM [121].Lin et al. [122] determined that atractylon had a protective effect against sleep-disordered breathing (SDB)-induced nerve cell injury and cognitive dysfunction (CD) via decreasing chronic intermittent hypoxia (CIH)-induced CD and the expression of inflammatory factors in the hippocampal region by suppressing M1 microglial activation and the promotion of M2 microglial activation.Moreover, the downregulation of sirtuin 3 decreased the protective effect of atractylon against CIH-induced microglial cell injury.

Activity in Gastrointestinal System
AT-I stimulates intestinal epithelial cell migration and proliferation via the polyaminemediated Ca 2+ signaling pathway, and it may be further developed as a promising therapeutic agent to treat diseases associated with gastrointestinal mucosal injury [126].AT-III significantly and dose-dependently suppressed gastric ulcer formation via inhibiting matrix metalloproteinase (MMP)-2 and MMP-9 expression, decreasing the extracellular matrix (ECM) damage and preventing gastric ulcer formation [127].Nogami et al. [128] demonstrated that β-eudesmol markedly inhibited ulcers in Shay rats, as well as histamine-and aspirin-induced gastric ulcers, and showed antisecretory activity on gastric acid secretion stimulated by histamine in a perfused rat stomach preparation.A remarkable antagonistic effect of β-eudesmol against the increased gastrointestinal movement induced by neostigmine was observed in vivo (p < 0.05).Improvements such as an increase in body weight and the normalization of gastrointestinal movement were observed after treatment with β-eudesmol in spleen-deficient mice [129].Kimura et al. [130] further determined that an extract of A. lancea and β-eudesmol may stimulate gastric emptying or small intestinal motility by inhibiting the dopamine D 2 receptor and 5-hydroxytryptamine 3 (HT 3 ) receptor.AT-I could increase fecal water content, accelerate intestinal peristalsis, and thus improve the symptoms of constipation in rats via improving intestinal flora disturbance and increasing the content of acetic acid and propionic acid [131].Atractyloside A improved gastrointestinal function by protecting the intestinal mucosal barrier via the inhibition of the p38 MAPK pathway [132].Animal studies further demonstrated that the processing of A. lancea had more satisfactory effects than the crude in treatment of gastric ulcers.The antiulcer effects of A. lancea could be attributed to the anti-inflammatory properties via downregulating TNF-α, interleukin 6 (IL-6), IL-8, and prostaglandin E 2 (PGE 2 ) to the gastroprotective effects via upregulating epidermal growth factor (EGF) and trefoil factor2 (TFF2) [133].Zhang et al. [134] investigated the effects of essential oils extracted from A. lancea on delayed gastric emptying, gastrointestinal hormone, and hypothalamic corticotropin-releasing factor (CRF) abnormalities induced by restraint stress in rats.The results suggested that the regulative effects of the essential oils on delayed gastric emptying are preformed mainly via inhibiting the release of central CRF and the activation of the vagal pathway, which are also involved in the release of gastrointestinal hormones such as motilin, gastrin, and somatostatin.Nakai et al. [135] discovered that an aqueous extract of A. lancea may improve both the delays in gastric emptying and ulcers.

Miscellaneous Activities
Yu et al. [136] discovered that AT-I could alleviate cerebral ischemia/reperfusion injury by reducing apoptosis and inflammatory responses through the inactivation of the nuclear factor-κB pathway.Additionally, AT-I mediated protective effects against acetaminophen-induced hepatotoxicity via the TLR4/MAPKs/NF-κB pathways, which attenuated the APAP-induced activation of TLR4, NF-κB, and MAPKs (including JNK and p38) [137].Wang et al. [138] discovered that AT-III ameliorated bile duct ligation (BDL)induced liver fibrosis by inhibiting the PI3K/AKT signaling pathway, as well as regulating the glutamine metabolic pathway.According to Chen et al. [139], AT-II and AT-III not only reduced agonist-induced platelet aggregation and ATP secretion, downregulated p-Akt and p-p38 MAPK levels, and inhibited platelet proliferation and clot contraction but also prolonged the time to first occlusion and prolonged bleeding.The administration of AT-I (1-300 µg/mL) or AT-III (1-300 µg/mL) to mesenchymal stem cells was found to significantly increase the expression of specific chondrogenic markers, including collagen gel aggrecan, Sox9, sonic hedgehog (Shh) and its target gene Gli-1.These effects indicate that atractylenolides may enhance chondrogenic differentiation by activating the Shh pathway [140].The sesquiterpenoid extracted from A. lancea showed the inhibition of blood vessel development in zebra fish embryos, which became much more expressive with an increase in concentration.Vegfaa gene expression were downregulated by β-eudesmol at all concentrations.For zebra fish embryos, β-eudesmol and atractylodin were lethal, showing the antiangiogenic property of A. lancea extracts [141].Tsuneki et al. [142] determined that β-eudesmol significantly inhibited angiogenesis in subcutaneously implanted Matrigel plugs in mice and in adjuvant-induced granuloma in mice through the blockade of the ERK signaling pathway.

Conclusions
The structural characteristics, biosynthetic pathways, and biological activities of sesquiterpenes from Atractylodes DC. species have been updated and summarized in the present review.Over 160 sesquiterpenes have been isolated and identified from the genus; among them, eudesmane-type sesquiterpenes were the main structures found in this genus, which accounted for more than 60% of the total sesquiterpenes.Meanwhile, the possible biosynthetic pathways of five categories of sesquiterpenes were also deduced in this review.In addition, improving pharmacological mechanisms support the traditional use of Atractylodes DC.Nevertheless, more research is needed in this field as current studies are still insufficient, and further exploration is required for future advancements.The primary focus of research on Atractylodes DC. species has been directed toward A. lancea and A. macrocephala, with little attention given to other members of the genus; however, it is worth noting that these overlooked species also possess significant value in terms of their active chemical components, making them a valuable addition to Atractylodes DC. resources.The mechanisms of their pharmacological activities, especially their antibacterial and antiviral activity, have not yet been clarified.Atractylon, at an appropriate concentration, can significantly inhibit the proliferation and promote the apoptosis of intestinal cancer cells via suppressing the PI3K/AKT/mTOR signaling pathway, which may be a potential candidate for the treatment of colorectal cancer and other related diseases.An additional investigation is warranted to delve into the therapeutic effectiveness, potential toxicity, and safety profiles of the active components, as well as to elucidate the correlation between chemical structure and biological activity, and to assess their practical use in clinical settings.

Table 6 .
Pharmacological activities of sesquiterpenoids from genus Atractylodes DC.