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The purpose of this paper is to explore the inhibitory effect of Xanthium sibiricum leaf extract on phytopathogenic fungi and clarify the antifungal active substance from Xanthium sibiricum. Taking wild Xanthium sibiricum leaf in Taigu Shanxi as the research object, its active components were extracted with 95% of ethano, preliminary isolation of antifungal substances was conducted by petroleum ether and ethyl acetate, and the main antifungal compounds were isolated and purfied by repeated silica gel column chromatography and recrystallization. The antifungal activities of the above components were analyzed by mycelial growth rate method and spore germination method. The results showed that the main antifungal compound in Xanthium sibiricum leaf was xanthatin, a sesquiterpene lactone. Xanthatin displayed good inhibitory effect on the mycelial growth of six tested plant pathogenic fungi, and the EC50 values of xanthatin against Bipolaris carbonum, Fusarium oxysporum, Fusarium graminearum, Fusarium solani, and Colletotrichum orbiculare were about 30 μg/mL. Xanthatin exhibited excellent germination inhibition activity on the spores of pathogenic fungi of four tested plants, especially had the most significant germination inhibition effect on the spores of Fusarium oxysporum and Botrytis cinerea with the EC50 values of 78.00, 15.22 μg/mL, respectively, which was far better than the effects of the positive controls, difenoconazole and hymexazol. This study confirmed that the sesquiterpene lactone xanthatin in Xanthium sibiricum leaf was the important substance foundation of antifungal activity, it not only displayed good inhibitory effect on the mycelial growth of plant pathogenic fungi, but also was found to have strong inhibitory germination activity on the spores of plant pathogenic fungi for the first time, indicating that it possessed a great potential of development of a new botanic antifungal agent. [ABSTRACT FROM AUTHOR]

[Display omitted] • Xanthiumines A and B possess a unique C 28 fused skeleton. • Xanthiumines A and B are the first examples of natural protoberberine alkaloid with a phenolic acid group at C-13a. • Xanthiumine A has significant triglyceride-lowering effects and reduces hepatic lipid accumulation. • Xanthiumine A could strongly target AMPKα catalytic subunit. • Xanthiumine A could activate AMPK pathway. Two protoberberine alkaloids with a unique C 28 skeleton, named xanthiumines A (1) and B (2), respectively, were isolated from the fruits of Xanthium sibiricum Patr. Their structures including absolute configurations were unequivocally established by the comprehensive NMR and MS spectroscopic data analysis together with gauge-independent atomic orbital (GIAO) NMR calculations, and electronic circular dichroism (ECD) calculations. Compounds 1 and 2 are the first examples of natural protoberberine alkaloid with a phenolic acid group at C-13a. Their plausible biosynthetic pathway was proposed on the basis of the coexisting alkaloid monomer as the precursor. Furthermore, the effects and related molecular mechanism of compound 1 on hepatic lipid accumulation were also investigated in oleic acid (OA)-treated HepG2 cells. [ABSTRACT FROM AUTHOR]

Sesquiterpene lactones (STLs) from the cocklebur Xanthium sibiricum exhibit significant anti-tumor activity. Although germacrene A oxidase (GAO), which catalyzes the production of Germacrene A acid (GAA) from germacrene A, an important precursor of germacrene-type STLs, has been reported, the remaining GAOs corresponding to various STLs' biosynthesis pathways remain unidentified. In this study, 68,199 unigenes were studied in a de novo transcriptome assembly of X. sibiricum fruits. By comparison with previously published GAO sequences, two candidate X. sibiricum GAO gene sequences, XsGAO1 (1467 bp) and XsGAO2 (1527 bp), were identified, cloned, and predicted to encode 488 and 508 amino acids, respectively. Their protein structure, motifs, sequence similarity, and phylogenetic position were similar to those of other GAO proteins. They were most strongly expressed in fruits, according to a quantitative real-time polymerase chain reaction (qRT-PCR), and both XsGAO proteins were localized in the mitochondria of tobacco leaf epidermal cells. The two XsGAO genes were cloned into the expression vector for eukaryotic expression in Saccharomyces cerevisiae, and the enzyme reaction products were detected by gas chromatography–mass spectrometry (GC-MS) and liquid chromatography–mass spectrometry (LC-MS) methods. The results indicated that both XsGAO1 and XsGAO2 catalyzed the two-step conversion of germacrene A (GA) to GAA, meaning they are unlike classical GAO enzymes, which catalyze a three-step conversion of GA to GAA. This cloning and functional study of two GAO genes from X. sibiricum provides a useful basis for further elucidation of the STL biosynthesis pathway in X. sibiricum. [ABSTRACT FROM AUTHOR]

Seven new phenylpropanoids, including two pairs of enantiomers of 8-O-4′-type neolignans, named (±)-xanthiifructins A-B (1a/1b-2a/2b), a pair of simple phenylpropanoid derivatives (±)-xanthiifructins C (3a/3b), and a racemic phenylpropanoid derivative xanthiifructin D (4), together with four known analogues (5-8) were isolated from the fruits of Xanthium sibiricum. Racemic xanthiifructins A-C were separated on chiral HPLC columns. Their structures were elucidated by comprehensive spectroscopic data analysis and comparison with the literatures. The anti-inflammatory and cytotoxic activities were evaluated for all isolates. Among them, (-)-xanthiifructin C (3b) exhibited potent inhibitory effect against nitric oxide production in lipopolysaccharide-activated RAW 264.7 mouse macrophage cells with an IC50 value of 9.94 ± 0.57 μM. All compounds obviously were inactive for three human tumor cell lines (MCF-7, HepG2, and A549) with IC50 values much more than 10 μM. [ABSTRACT FROM AUTHOR]

Hybridization is one of the important factors influencing the adaptive evolution of invasive plants. According to previous studies, hybridization with an invasive plant reduces the adaptability of its native congener to environment. However, in this study, the hybridization with an invasive plant of Xanthium strumarium (LT) improves the tolerance and accumulation of its native congener Xanthium sibiricum (CR) to cadmium (Cd). Under Cd stress, X. sibiricum ♀ × X. strumarium ♂ (ZCR) showed higher biomass and Cd accumulation. Compared with CR, ZCR has longer vegetative and reproductive growth time. Moreover, ZCR adopted more reasonable biomass allocation strategy. ZCR increased the proportion of reproductive allocation and ensured its own survival with the increase of Cd stress. Furthermore, ZCR increased the translocation of Cd to aboveground parts and changed the distribution of Cd. A large amount of Cd is stored in senescent leaves and eliminated from the plant when the leaves fall off, which not only reduces the Cd content in the plant, but also reduces the toxicity of Cd in the normal leaves. Transcriptome analysis shows a total of 2055 (1060 up and 995 down) differentially expressed genes (DEGs) were detected in the leaves of Cd-stressed ZCR compared with CR, while only 792 (521 up and 271 down) were detected in X. strumarium ♀ × X. sibiricum ♂ (ZLT) compared with LT. A large number of DGEs in ZCR and ZLT are involved in abscisic acid (ABA) synthesis and signal transduction. The genes induced by ABA in ZCR, including CNGC5/20, CPK1/28, CML, PTI1-like tyrosine-protein kinase 3, respiratory burst oxidase homolog protein C, and WRKY transcription factor 33 were found differentially expressed compared CR. carotenoid cleavage dioxygenase 4, NCED1/2, phytoene synthase 2, and CYP707A involved in ABA synthesis and decomposition in ZLT were found differentially expressed compared LT. We speculated that ABA played an important role in Cd transportation of hybrids and Cd distribution in senescent and normal leaves. The results demonstrate that hybridization with an invasive plant improves the adaptability of the hybrid to Cd stress and may enhance the extinction risk of native congener in pollution environment. [ABSTRACT FROM AUTHOR]

Sesquiterpene lactones (STLs) from the cocklebur Xanthium sibiricum exhibit significant anti-tumor activity. Although germacrene A oxidase (GAO), which catalyzes the production of Germacrene A acid (GAA) from germacrene A, an important precursor of germacrene-type STLs, has been reported, the remaining GAOs corresponding to various STLs’ biosynthesis pathways remain unidentified. In this study, 68,199 unigenes were studied in a de novo transcriptome assembly of X. sibiricum fruits. By comparison with previously published GAO sequences, two candidate X. sibiricum GAO gene sequences, XsGAO1 (1467 bp) and XsGAO2 (1527 bp), were identified, cloned, and predicted to encode 488 and 508 amino acids, respectively. Their protein structure, motifs, sequence similarity, and phylogenetic position were similar to those of other GAO proteins. They were most strongly expressed in fruits, according to a quantitative real-time polymerase chain reaction (qRT-PCR), and both XsGAO proteins were localized in the mitochondria of tobacco leaf epidermal cells. The two XsGAO genes were cloned into the expression vector for eukaryotic expression in Saccharomyces cerevisiae, and the enzyme reaction products were detected by gas chromatography–mass spectrometry (GC-MS) and liquid chromatography–mass spectrometry (LC-MS) methods. The results indicated that both XsGAO1 and XsGAO2 catalyzed the two-step conversion of germacrene A (GA) to GAA, meaning they are unlike classical GAO enzymes, which catalyze a three-step conversion of GA to GAA. This cloning and functional study of two GAO genes from X. sibiricum provides a useful basis for further elucidation of the STL biosynthesis pathway in X. sibiricum.

Purpose: To investigate the protective effects of 4, 5-O-dicaffeoylquinic acid (DCQA) isolated from Xanthium sibiricum Patr. against mouse sepsis caused by cecal ligation/puncture (CLP) in vivo, as well as the molecular mechanisms of action involved. Methods: DCQA (7.5, 15, and 30 mg/kg/day) were administered to the mice with sepsis and the survival rate was obtained. Tumor necrosis factor (TNF)-α and interleukin (IL)-6 were examined by enzyme-linked immunosorbent assay (ELISA). Subsequently, the lipopolysaccharide (LPS) neutralizing ability of DCQA (2, 4, and 8 μg/mL) was measured using limulus amebocyte lysate (LAL) test in vitro. Furthermore, the effect of DCQA (10, 20, and 40 μg/mL) on mRNA expression of TNF-α, IL-6, and IL-8 in LPS (100 ng/mL)-treated RAW 264.7 cells was assessed using quantitative real time-polymerase chain reaction (RT-qPCR) assay. Results: DCQA significantly improved the survival rate of mice with sepsis caused by CLP (35, 50, and 65 %, respectively vs. 15 % for control, p < 0.05). LPS levels fell on co-incubation with DCQA in vitro. Moreover, ELISA and RT-qPCR results revealed that DCQA treatment lowered tendency in the mRNA expression of TNF-α, IL-6, and IL-8 (p < 0.01). Conclusion: DCQA exhibits protective effects against sepsis in mice mediated by downregulating TNF-α, IL-6, and IL-8. Further studies, in animals and humans are requied to determine the safety and efficacy of DCQA in both animal and clinical management of sepsis. [ABSTRACT FROM AUTHOR]

Xanthium sibiricum is a common and annual the Traditional Chinese Medicine for many years in China. In this study, we presented the complete chloroplast genome of X. sibiricum. The chloroplast genome size was 151,897 bp in length that contained a large single-copy region (LSC) of 83,847 bp, a small single-copy region (SSC) of 17,890 bp and two inverted repeat regions (IR) of 25,080 bp. The overall nucleotide composition of the chloroplast genome is: 31.2% of A, 31.3% T, 18.5% C and 19.0% G, with a total G + C content of the chloroplast genome 37.5% and A + T of 62.5%. The chloroplast genome of X. sibiricum contains 133 genes, which included 88 protein-coding genes (PCG), 37 transfer RNA (tRNAs), and 8 ribosome RNA (rRNAs). Phylogenetic neighbour-joining (NJ) analysis result shown that the position of X. sibiricum closely related to X. strumarium in evolutionary relationship.

We studied the chemical constituents and bioactivity of Xanthium sibiricum, and fourteen compounds were isolated from the PE and EtOAc extract by the methods of column chromatography, thin layer chromatography, semi-prepared HPLC, and recrystallization. The structures were elucidated by the analysis of spectral data and physical-chemical properties and identified as anisic acid (1), taraxerol (2), lupeol (3), ursolic acid (4), stimastero (5), oleanolic acid(6), lasidiol p-methoxybenzoate (7), lupe-none(8), xanthatin (9), α-spinasterol (10), quercetin (11), xanthinosin (12), apigenin (13) and oleanic acid (14); Compounds 2,7,8 were isolated from Xanthium sibiricum for the first time. The compounds were tested by plate diffusion method for the inhibitory effect of different strains. The results showed that the compounds taraxerol (2), lupe-none (8), xanthatin (9) and xanthinosin (12) displayed antibacterial activity to Alternaria solani, Fusarium oxysporum. sp. susumebrium, Botrytis cinerea and Cytospora sp. [ABSTRACT FROM AUTHOR]

The traditional Chinese medicine Xanthium sibiricum Patrin ex Widder is used to treat wind-cold headache, nasal congestion, nasal discharge, allergic rhinitis, sinusitis, urticaria, and arthritis. Our previous studies found that sesquiterpene lactones, the main bioactive constituents of X. sibiricum , relieved airway inflammation in an asthma mouse model. To obtain active sesquiterpenes, five undescribed ones, including a pair of eremophilanes and three xanthanolides, together with eight known xanthanolides were isolated from X. sibiricum. Their structures were identified by IR, UV, HR-ESI-MS and NMR spectroscopic data, and their absolute configurations were determined by X-ray crystallographic diffraction analysis and the comparison between their experimental and calculated electronic circular dichroism. All isolated compounds were evaluated for their inhibitory effects on nitric oxide production, and Tnf-α, Il-1β, and Il-6 mRNA expression induced by lipopolysaccharide in the macrophage cell line RAW264.7. Further investigation showed that xanthsibiriolide and 11 β -hydroxyl-13-chloro-8- epi -xanthatin exerted their anti-inflammatory effects by inhibiting the PI3K/AKT/mTOR signaling pathway. Analysis of the structure-activity relationships indicated that the α , β -unsaturated lactone ring and the 1,5-epoxide group might be the bioactive groups of xanthanolides, and these results provide a basis for further exploration of sesquiterpene-type lead compounds with anti-inflammatory activity. Five undescribed sesquiterpenes, including a pair of eremophilane-type sesquiterpenoid epimers and three xanthanolide-type sesquiterpenoids, together with eight known xanthanolide sesquiterpenoids were isolated from Xanthium sibiricum Patrin ex Widder. All the isolated sesquiterpenes were evaluated for their anti-inflammatory activities. [Display omitted] • Five undescribed sesquiterpenes were isolated from Xanthium sibiricum Patrin ex Widder. • Their structures were determined based on NMR, X-ray diffraction, and calculated ECD. • All isolated compounds were evaluated for their anti-inflammatory activities. • The α , β -unsaturated lactone ring and 1,5-epoxide group maybe bioactive groups of xanthanolides. [ABSTRACT FROM AUTHOR]

Ethnopharmacological relevance Xanthium sibiricum has been used as a traditional Chinese medicine for the treatment of appendicitis, bronchitis, arthritis, and other inflammatory ailments. However, its pharmacological activity related to an anti-inflammatory effect remain unknown. This present study aims to investigate the anti-inflammatory effect of methanol extracts of X. sibiricum roots (MXS), and to further determine its underlying mechanism of action in order to assess the medicinal value of X. sibiricum roots. Materials and methods To assess the anti-inflammatory activity of MXS in lipopolysaccharides (LPS)‑stimulated RAW 264.7 macrophages, the production of nitric oxide (NO) was measured using the Griess reagent system. The levels of pro-inflammatory cytokines and mediators were quantified using an Enzyme-linked immunosorbent assay (ELISA) and reverse transcription polymerase chain reaction (RT-PCR). Subsequently, immunoblotting analyses were employed to detect inflammatory mediators as well as to elucidate the underlying regulatory mechanisms suppressed by MXS. Results MXS inhibited LPS-stimulated NO production and inducible nitric oxide synthase (iNOS) expression in RAW 264.7 macrophages within the non-cytotoxic concentration range (50–400 μg/ml). In addition, mRNA and protein levels of pro-inflammatory cytokines such as interleukin (IL)-6, IL-1β, and tumor necrosis factor (TNF)-α were significantly suppressed by MXS at the concentration of 400 μg/ml. Furthermore, MXS (200 μg/ml) clearly reduced the phosphorylation levels of the inhibitor of kappa Bα (IκBα) and signal transducer and activator of transcription 3 (STAT3), without affecting changes in the phosphorylation levels of mitogen-activated protein kinases (MAPKs). When five major components (betulin, betulinic acid, β-sitosterol, stigmasterol, and scopoletin) of MXS were separately investigated, stigmasterol and β-sitosterol seemed to play major inhibitory roles in the LPS-induced production of inflammatory mediators such as NO, IL-6, and TNF-α. Conclusion Our results demonstrate that MXS has an anti-inflammatory property in LPS-stimulated RAW 264.7 macrophages, and its anti-inflammatory activity is exerted by the regulation of nuclear factor-κB (NF-κB) and STAT3 signaling pathways. [ABSTRACT FROM AUTHOR]

Three new compounds (1–3), together with six known compounds (4–9), were isolated from the fruits ofXanthium sibiricum.The structures and the absolute configurations of sibiricumthionol (1), (+)-(5Z)-6-methyl-2-ethenyl-5-hepten-1,2,7-triol [(+)-2], ( − )-(5Z)-6-methyl-2-ethenyl-5-hepten-1,2,7-triol [( − )-2], (2E,4E,1′S, 2′R, 4′S, 6′R)-dihydrophaseic acid (3), (+)-xanthienopyran[(+)-4]and ( − )-xanthienopyran [( − )-4]were established by extensive spectroscopic analyses, X-ray crystallographic analysis, ECCD analysis and ECD calculations. Caffeic acid (7) and caffeic acid ethyl ester (8) weekly inhibited α-glucosidase enzymatic activity by 44.5% and 40.2%, respectively, at 40 μM. Protocatechuic acid (9) selectively exhibited cytotoxicity against HepG2 cell lines, with an IC50value of 2.92 μM. [ABSTRACT FROM PUBLISHER]

The fuel properties of coastal plant Xanthium sibiricum were investigated in thermogravimetrics. The distributed activation energy model was employed in the kinetic analysis and a simplified mathematical model that can predict the thermogravimetry curves was proposed. The results show that the initial decomposition temperature tends to increase with the heating rate. The distributed E values ranged from 169.08 to 177.43 kJ/mol, and the frequency factor values ranged from 6.59×10 to 1.22×10/s at different conversion rates. Furthermore, the prediction made with the simplified mathematical model perfectly matched the experimental data, and the model was found to be simple and accurate for the prediction of devolatilization curves. [ABSTRACT FROM AUTHOR]

A phytochemical investigation on the fruits of Xanthium sibiricum Patrin ex Widder led to the isolation of twenty compounds. Their structures were elucidated by comparison with relevant spectroscopic data. To the best of our knowledge, compounds 3 , 7 , 13 – 15 were isolated from the family Compositae for the first time. Compounds 2 , 4 , 8 , 20 , along with compounds 11 , 12 , 16 , 17 were firstly reported from the genus Xanthium and species X. sibiricum , respectively. Additionally, chemotaxonomic investigation revealed the close relationship between X. sibiricum and Xanthium strumarium L. • Five compounds were isolated from the family Compositae for the first time. • Four compounds were firstly reported from the genus Xanthium. • Four compounds were firstly reported from the species Xanthium sibiricum Patrin ex Widder. • Close relationship between X. sibiricum and Xanthium strumarium L. was revealed in the present chemotaxonomic investigation. [ABSTRACT FROM AUTHOR]

In order to improve the phytoextraction efficiency of Xanthium sibiricum on farmland soil that had been contaminated by Cd and As, this study explored the effects of chelating agents and organic acids (EDTA, SAP, CA, and MA) on the extraction of Cd and As heavy metals using X. sibiricum . The results showed that the four different chelating agents and organic acids had little effect on the biomass of the roots, stems, and leaves of X. sibiricum . However, they had different effects on the concentrations and accumulation of Cd and As in various organs of X. sibiricum . Compared with the those in the CK treatment, EDTA, SAP, CA, and MA significantly increased the Cd concentrations in the leaves of X. sibiricum by 44.1%, 32.4%, 41.2%, and 38.2% and the As concentrations in the roots of X. sibiricum by 89.6%, 7.4%, 94.8%, and 61.5%, respectively. The four treatments (EDTA, SAP, CA, and MA) improved the total Cd accumulation of X. sibiricum, with increasing ranges, respectively, of 70.2%, 29.4%, 28.9%, and 33.1%, and the As accumulation increased by 67.0%, 19.6%, 81.9%, and 40.8%, respectively, compared with that of the CK treatment. The four chelating agents and organic acids had different effects on the Cd and As bioconcentration factor and transfer factor of various organs of X. sibiricum . Treatments with EDTA, SAP, CA, and MA resulted in a decrease of 32.7%-38.2% in soil Cd concentrations and a decrease of 14.6%-20.5% in soil As concentrations. These four chelating agents can be used for enhancing the efficiency of extraction Cd and As heavy metals by X. sibiricum .

Xanthium sibiricum is a common and annual the Traditional Chinese Medicine for many years in China. In this study, we presented the complete chloroplast genome of X. sibiricum. The chloroplast genome size was 151,897 bp in length that contained a large single-copy region (LSC) of 83,847 bp, a small single-copy region (SSC) of 17,890 bp and two inverted repeat regions (IR) of 25,080 bp. The overall nucleotide composition of the chloroplast genome is: 31.2% of A, 31.3% T, 18.5% C and 19.0% G, with a total G + C content of the chloroplast genome 37.5% and A + T of 62.5%. The chloroplast genome of X. sibiricum contains 133 genes, which included 88 protein-coding genes (PCG), 37 transfer RNA (tRNAs), and 8 ribosome RNA (rRNAs). Phylogenetic neighbour-joining (NJ) analysis result shown that the position of X. sibiricum closely related to X. strumarium in evolutionary relationship. [ABSTRACT FROM AUTHOR]

Abstract: The EtOH extract of the aerial parts of Xanthium sibiricum afforded six sesquiterpene lactones (STLs), including two new eremophilanolides. The structures of the new compounds were established on the basis of spectroscopic methods and the modified Mosher''s method to be the C-11 epimers of 2S,4S,5R,7R,8R-2-hydroxy-eremophil-1(10)-en-12,8-olide [11R: 1 (sibiriolide C); 11S: 2 (sibiriolide D)]. The isolated compounds were evaluated for their in vitro cytotoxicities against five human cancer cell lines (Huh-7 hepatocarcinoma, KB nasopharynx carcinoma, Jurkat T cell lymphoblast, BGC-823 and KE-97 gastric carcinoma) using the CellTiter-Glo™ luminescent cell viability assay method. Compounds 4–6, each possessing an α-methylene-γ-lactone moiety, were found to have noteworthy cytotoxic effects with IC50 values ranging from 1.1 to 18.0μM. [Copyright &y& Elsevier]

Xanthium sibiricum patrin ex Widder (Compositae) is an annual herb which grows all around China. Chemical investigations of its roots resulted in the identification of 15 compounds: stigmast-4-en-6β-ol-3-one (1), β-sitostenone (2), β-sitosterol (3), nonadecanoic acid (4), 5α,8α-epidioxy-22E-ergosta-6,22-dien-3β-ol (5), scopoletin (6), Jatrocin B (7), (±)syringaresinol (8), 9,9'-O-di-(E)-feruloyl-(-)-secoisolariciresinol (9), cleomiscosin A (10), cleomiscosin C (11), N-trans-feruloyl tyramine (12), daucosterol (13), 5-methyluracil (14) and uracil (15). Structures were elucidated by spectroscopic (NMR and MS) methods and confirmed by comparing with reference samples and literature data. Compounds 1-2, 4-12, 14, and 15 were isolated from this genus for the first time, while this is the first report of coumarinolignoids in the Compositae family, and coumarinoligoids could be considered as valuable chemotaxonomic markers for the plant. [ABSTRACT FROM AUTHOR]

An experiment was conducted to investigate plasticity of meristem allocation under intraspecific competition in three annual species (Xanthium sibiricum Patrin., Datura stramonium L., and Fagopyrum esculentum Moench.) with different architectures (monopodial, false dichotomous, and sympodial branching, respectively). There were two density treatments for X. sibiricum and D. stramonium, with plant–plant distances of 7 and 14 cm, and five density treatments for F. esculentum, with plant–plant distances of 5, 10, 15, 20, and 25 cm. We recorded meristem fates (inactive, growth, and reproduction) at several developmental stages and at the final developmental stage. Allocation of meristems to reproduction in all three species could be explained by allometric growth (“apparent plasticity”), but meristem allocation patterns to the other functions differed among the species. Allocation of meristems to growth affects and is affected by plant architecture. Our results suggest that vegetative growth is more plastic than reproduction in annual plants. [ABSTRACT FROM AUTHOR]

Two new eremophilanolides, sibiriolides A (1) and B (2), were isolated from the aerial parts of Xanthium sibiricum. The structures of the new compounds were identified as 4S,5R,7R,8R, 11R-2-oxo-1(10)-eremophilen-12,8-olide (1) and 4S,5R,7R,8R,11S-2-oxo-1(10)-eremophilen-12,8-olide (2) by HREIMS and NMR spectroscopic techniques in combination with X-ray crystallographic analysis and CD measurements. [ABSTRACT FROM AUTHOR]

A novel sulphur-containing compound named xanthiazinone (1) was isolated from the ethanolic extract of the fruits of Xanthium sibiricum, along with four known compounds, xanthiazone (2), xanthiside (3), xanthienopyran (4) and 5-hydroxypyrrolidin-2-one (5). Their structures were determined on the basis of spectroscopic techniques. [ABSTRACT FROM AUTHOR]

Seven previously undescribed sulfur-containing compounds, (+)- and (−)-xanthiazinone A, (+)- and (−)-xanthiazinone B, (+)- and (−)-xanthiazinone C and xanthiazinone D, and four known thiazinedione derivatives, together with three thiophene derivatives were isolated from the fruits of Xanthium sibiricum. Racemic xanthiazinones A-C were separated by chiral HPLC columns. Their chemical structures were elucidated based on extensive spectroscopic analyses, ECD calculations, and single crystal X-ray diffractions. The X-ray crystallographic analyses for xanthiazinones A-C represent the first example described for the structure elucidation of the thiazinedione with the five-membered lactone ring attached via an oxygen atom. Accordingly, the previously proposed structure for xanthiazinone was revised. The anti-inflammatory and cytotoxic activities were evaluated for all the isolated compounds. (+)-xanthiazinone B and 2-hydroxy-xanthiazone exhibited potent inhibitory effects against nitric oxide production in lipopolysaccharide-activated RAW 264.7 mouse macrophage cells with IC 50 values of 8.75 and 10.90 μM, respectively. All compounds obviously were inactive for three human tumor cell lines (HepG2, MCF-7, and A549) with IC 50 values more than 10 μM. Seven previously undescribed thiazinedione derivatives together with seven known sulfur-containing compounds were isolated from the fruits of Xanthium sibiricum. Two compounds exhibited potent anti-inflammatory activity. Image 1 • Seven undescribed xanthiazinones were isolated from the fruits of Xanthium sibiricum. • Three pairs of enantiomers were successfully separated by chiral HPLC columns. • The previously reported structure for xanthiazinone was revised. • (+)-Xanthiazinone B and 2-hydroxy-xanthiazone exhibited potent anti-inflammatory activity. [ABSTRACT FROM AUTHOR]

The taxonomic position of a novel actinomycete isolate, designated strain GGCR-6 T , isolated from the healthy leaves of Xanthium sibiricum collected from the botanic garden of Hunan University of Science and Technology in Hunan province, PR China, was determined by a polyphasic approach. GGCR-6 T grew well on ISP series media and formed well-developed, branched substrate hyphae and aerial mycelium that differentiated into straight spore chains consisting of cylindrical spores with smooth surfaces. The diagnostic diamino acid was ll-diaminopimelic acid. The major menaquinones were MK-9(H 8 ), MK-9(H 2 ), MK-9 and MK-9(H 6 ). The polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphotidylinositol and phosphatidylinositol mannosides. The predominant fatty acids were C 16 : 1 ω9 c , iso-C 16 : 0 and C 16 : 0 . The phenotypic characteristics of GGCR-6 T indicated that it represented a member of the genus Streptomyces . Phylogenetic analysis based on the 16S rRNA gene sequence indicated that GGCR-6 T was most closely related to Streptomyces cyaneus NRRL B2296 T and Streptomyces griseoruber NRRL B1818 T . However, the digital DNA-DNA hybridization, the average nucleotide identity and the multi locus sequence analysis evolutionary distance clearly separate GGCR-6 T from the phylogenetically closely related species. Furthermore, the novel isolate was distinctly differentiated from S. cyaneus NRRL B2296 T and S. griseoruber NRRL B1818 T by morphological, physiological and biochemical characteristics. Based on these data, strain GGCR-6 T should be designated as a representative of a novel species of the genus Streptomyces , for which the name Streptomyces aquilus sp. nov. is proposed. The type strain is strain GGCR-6 T (=CICC 11055 T =JCM 33584 T ).

Xanthium sibiricum is a common and annual the Traditional Chinese Medicine for many years in China. In this study, we presented the complete chloroplast genome of X. sibiricum . The chloroplast genome size was 151,897 bp in length that contained a large single-copy region (LSC) of 83,847 bp, a small single-copy region (SSC) of 17,890 bp and two inverted repeat regions (IR) of 25,080 bp. The overall nucleotide composition of the chloroplast genome is: 31.2% of A, 31.3% T, 18.5% C and 19.0% G, with a total G + C content of the chloroplast genome 37.5% and A + T of 62.5%. The chloroplast genome of X. sibiricum contains 133 genes, which included 88 protein-coding genes (PCG), 37 transfer RNA (tRNAs), and 8 ribosome RNA (rRNAs). Phylogenetic neighbour-joining (NJ) analysis result shown that the position of X. sibiricum closely related to X. strumarium in evolutionary relationship., (© 2020 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.)

By retrieving domestic and foreign literatures, the authors provided a systematic review for effects of Xanthii Fructus, toxicity recorded in ancient/current literatures and relevant toxicological experience, and summarized clinical characteristics of clinical cases related to Xanthii Fructus and influencing factors. In addition to liver and kidney injuries as the major side effects of Xanthii Fructus, neurotoxicity and cardio-toxicity of Xanthii Fructus were also common clinical adverse events. However, there have been a few animal experimental studies so far. Oral administration and external application with Xanthii Fructus have often caused skin reactions, even such severe cases as exfoliative dermatitis. The authors suggested standardizing the clinical medication, avoiding to use untreated prescriptions and unprocessed herbs, ensuring the effective and safety use of Xanthii Fructus in strict accordance with the recommended dosage and usage in pharmacopeia, paying attention to the accumulation of safety signals, strengthening studies on toxic substance, toxicity mechanism, and synergy and attenuation effects., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Chinese Pharmaceutical Association.)