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1.
Front Plant Sci ; 14: 1016890, 2023.
Article in English | MEDLINE | ID: mdl-37554555

ABSTRACT

Winter wheat is one of the major food crops in China, and timely and effective early-season identification of winter wheat is crucial for crop yield estimation and food security. However, traditional winter wheat mapping is based on post-season identification, which has a lag and relies heavily on sample data. Early-season identification of winter wheat faces the main difficulties of weak remote sensing response of the vegetation signal at the early growth stage, difficulty of acquiring sample data on winter wheat in the current season in real time, interference of crops in the same period, and limited image resolution. In this study, an early-season refined mapping method with winter wheat phenology information as priori knowledge is developed based on the Google Earth Engine cloud platform by using Sentinel-2 time series data as the main data source; these data are automated and highly interpretable. The normalized differential phenology index (NDPI) is adopted to enhance the weak vegetation signal at the early growth stage of winter wheat, and two winter wheat phenology feature enhancement indices based on NDPI, namely, wheat phenology differential index (WPDI) and normalized differential wheat phenology index (NDWPI) are developed. To address the issue of " different objects with the same spectra characteristics" between winter wheat and garlic, a plastic mulched index (PMI) is established through quantitative spectral analysis based on the differences in early planting patterns between winter wheat and garlic. The identification accuracy of the method is 82.64% and 88.76% in the early overwintering and regreening periods, respectively, These results were consistent with official statistics (R2 = 0.96 and 0.98, respectively). Generalization analysis demonstrated the spatiotemporal transferability of the method across different years and regions. In conclusion, the proposed methodology can obtain highly precise spatial distribution and planting area information of winter wheat 4_6 months before harvest. It provides theoretical and methodological guidance for early crop identification and has good scientific research and application value.

2.
Biotechnol Appl Biochem ; 70(2): 553-559, 2023 Apr.
Article in English | MEDLINE | ID: mdl-35725894

ABSTRACT

Mycoplasma pneumoniae is a highly infectious bacterium and the major cause of pneumonia especially in school-going children. Mycoplasma pneumoniae affects the respiratory tract, and 25% of patients experience health-related problems. It is important to have a suitable method to detect M. pneumoniae, and gold nanoparticle (GNP)-based colorimetric biosensing was used in this study to identify the specific target DNA for M. pneumoniae. The color of GNPs changes due to negatively charged GNPs in the presence of positively charged monovalent (Na+ ) ions from NaCl. This condition is reversed in the presence of a single-stranded oligonucleotide, as it attracts GNPs but not in the presence of double-stranded DNA. Single standard capture DNA was mixed with optimal target DNA that cannot be adsorbed by GNPs; under this condition, GNPs are not stabilized and aggregate at high ionic strength (from 100 mM). Without capture DNA, the GNPs that were stabilized by capture DNA (from 1 µM) became more stable under high ionic conditions and retaining their red color. The GNPs turned blue in the presence of target DNA at concentrations of 1 pM, and the GNPs retained a red color when there was no target in the solution. This method is useful for the simple, easy, and accurate identification of M. pneumoniae target DNA at higher discrimination and without involving sophisticated equipment, and this method provides a diagnostic for M. pneumoniae.


Subject(s)
Metal Nanoparticles , Mycoplasma pneumoniae , Child , Humans , Mycoplasma pneumoniae/genetics , Gold , Colorimetry/methods , DNA , Ions
3.
Fitoterapia ; 154: 105002, 2021 Oct.
Article in English | MEDLINE | ID: mdl-34324974

ABSTRACT

Four previously unreported sesquiterpenoid diasteromers, arteannoides U-X (1-4), together with one new norsesquiterpenoid 5 (arteannoide Y) and one undescribed rearranged cadinene sesquiterpenoid 6 (arteannoide Z) were obtained from the dried aerial parts of Artemisia annua (Qinghao). Notably, arteannoides U-X (1-4) are four stereoisomers that possess the same molecules and the same planar connectivity, but differ from each other in configuration at a certain stereocenter. Their accurate structures were unambiguously identified and distinguished by extensive spectroscopic analyses, NMR calculations with DP4+ analysis, electronic circular dichroism (ECD) calculations and X-ray diffraction analyses. Compounds 1, 3, and 4 showed inhibitory activities against the production of inflammatory cytokines (PGE2, NO, IL-6 and TNF-α) in lipopolysaccharide (LPS)-induced RAW 264.7 macrophages.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Artemisia annua/chemistry , Sesquiterpenes/pharmacology , Animals , Anti-Inflammatory Agents/isolation & purification , China , Cytokines , Mice , Molecular Structure , Nitric Oxide , Phytochemicals/isolation & purification , Phytochemicals/pharmacology , Plant Components, Aerial/chemistry , RAW 264.7 Cells , Sesquiterpenes/isolation & purification
4.
Zhongguo Zhong Yao Za Zhi ; 46(5): 1160-1167, 2021 Mar.
Article in Chinese | MEDLINE | ID: mdl-33787111

ABSTRACT

Chemical constituents were isolated and purified from the water extract of Artemisia annua by column chromatography of HP-20 macroporous resin, silica gel, ODS, Sephadex LH-20, HW-40, and semi-preparative RP-HPLC. Their structures were elucidated by physicochemical properties and spectral analyses. As a result, Fifteen compounds were isolated and identified as vitexnegheteroin M(1), sibricose A5(2), securoside A(3), citrusin D(4), annphenone(5), E-melilotoside(6), esculetin(7), scopoletin-7-O-ß-D-glucoside(8), eleutheroside B_1(9), chrysosplenol D(10), patuletin-3-O-ß-D-glucopyranoside(11), quercetin-7-O-ß-D-glucoside(12), rutin(13), apigenin 6,8-di-C-ß-D-glucopyranoside(14), isoschaftoside(15), among them, compounds 1-4 were identified from Artemisia for the first time. Additionally, the isolates were evaluated for their inhibitory effects on the production of PGE_2 in LPS-simulated RAW264.7 macrophages. The results showed that compounds 1, 2, 8, and 10-15 could reduce PGE_2 levels, to a certain extent.


Subject(s)
Artemisia annua , Apigenin , Quercetin , Rutin
5.
Bioorg Chem ; 103: 104221, 2020 10.
Article in English | MEDLINE | ID: mdl-32891001

ABSTRACT

Thirteen new sesquiterpenoids, arteannoides F-R (1-13), along with 13 known analogues (14-26), were isolated from the dried aerial parts of Artemisia annua L. Their structures, including absolute configurations, were unambiguously determined by a combination of physical data analyses (HRESIMS, 1D and 2D NMR, and ECD) as well as the crystal structures of 1, 5, 6, 15, 19, and 23. Among the isolated compounds, 1 features an unusual 11-oxatricyclo[6.2.1.04,9]undecan-2-ene ring system, 5 possesses an uncommon 4,11-ether bridged tricyclic framework, whereas 6 is a new eudesmane-type sesquiterpenoid formed via rearrangement of its carbon backbone. The systemically anti-inflammatory activities of all isolates were evaluated by measuring their inhibitory effects on PGE2, NO, TNF-α, and IL-6 production in LPS-stimulated RAW 264.7 macrophages. Moreover, the structure activity relationships of some compounds are summarized, this study will provide new structural templates for discovering potential anti-inflammatory agents.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Artemisia annua/chemistry , Plant Components, Aerial/chemistry , Sesquiterpenes, Eudesmane/pharmacology , Animals , Anti-Inflammatory Agents/chemistry , Anti-Inflammatory Agents/isolation & purification , Dinoprostone/antagonists & inhibitors , Interleukin-6/antagonists & inhibitors , Mice , Molecular Structure , Nitric Oxide/antagonists & inhibitors , RAW 264.7 Cells , Sesquiterpenes, Eudesmane/chemistry , Sesquiterpenes, Eudesmane/isolation & purification , Structure-Activity Relationship , Tumor Necrosis Factor-alpha/antagonists & inhibitors
6.
Nat Prod Res ; 34(21): 3108-3116, 2020 Nov.
Article in English | MEDLINE | ID: mdl-31264446

ABSTRACT

Two new cembrane diterpenoids, named populeuphrines A and B (1 and 2), together with three known analogues (3-5) were isolated from the resins of Populus euphratica. The planar structures and relative configurations of 1 and 2 were elucidated by detailed 1 D and 2 D NMR spectroscopic analyses. The absolute configurations of 1 and 2 were determined by X-ray diffraction analysis and quantum chemical computation. Biological activities of all the isolates against proliferation of human cancer cells and umbilical cord mesenchymal stem cells were evaluated.


Subject(s)
Diterpenes/chemistry , Diterpenes/pharmacology , Populus/chemistry , Resins, Plant/chemistry , Antineoplastic Agents, Phytogenic/chemistry , Antineoplastic Agents, Phytogenic/pharmacology , Cell Line, Tumor , Cell Proliferation/drug effects , Crystallography, X-Ray , Diterpenes/isolation & purification , Fetal Blood/cytology , Humans , Magnetic Resonance Spectroscopy , Mesenchymal Stem Cells/drug effects , Molecular Structure
7.
Molecules ; 24(23)2019 Nov 30.
Article in English | MEDLINE | ID: mdl-31801194

ABSTRACT

Two new octanorlanostane-type triterpenes, euphraticanoids A and B (1 and 2), two new trinorsesquiterpenoids, euphraticanoids C and D (3 and 4), and eight known triterpenoids (5, 6, 8-13) along with one steroid (7) were isolated from Populus euphratica resins. The structures of these new compounds, including their absolute configurations, were characterized by spectrocsopic, chemical, and computational methods. Biological evaluation revealed that compounds 4, 7-9, 12, and 13 display neuroprotective activities in H2O2-induced HT-22 cells with 4, 8, and 9 occurring in a concentration-dependent manner and 7, 12, and 13 reaching the maximum effects at 20 µM. Meanwhile, the neuroprotective properties of all isolates were accessed using glutamate-induced SH-SY5Y cells and disclosed that compounds 3, 4, 8, and 9 could dose-dependently protect neural cell injury in a concentration range of 10-40 µM. Finally, a brief structure-activity relationship was briefly discussed.


Subject(s)
Neuroprotective Agents/chemistry , Neuroprotective Agents/pharmacology , Populus/chemistry , Resins, Plant/chemistry , Sesquiterpenes/chemistry , Sesquiterpenes/pharmacology , Triterpenes/chemistry , Triterpenes/pharmacology , Magnetic Resonance Spectroscopy , Molecular Structure , Structure-Activity Relationship
8.
Molecules ; 24(8)2019 Apr 15.
Article in English | MEDLINE | ID: mdl-30991677

ABSTRACT

Four new compounds including two new sesquiterpenoid dimers, commiphoroids E (1) and F (2), a new triterpenoid (3), and a new sesquiterpenoid (4), along with three known terpenoids (5-7) were isolated from Resina Commiphora, whose structures were identified by NMR spectra, HRESIMS, and X-ray diffraction analysis. Compounds 1 and 2 both bear an O-bridge ring and feature a plausible [4 + 2] Diels-Alder cycloaddition reaction. Antimycobacterial activities show that all the tested compounds (200 µM) could inhibit the growth of both sensitive and clinically multi-drug resistant (MDR) isolated strains. In addition, cellular toxicity of the isolates against human cancer cells and THP-1 monocyte cells was examined.


Subject(s)
Antitubercular Agents , Commiphora/chemistry , Mycobacterium tuberculosis/growth & development , Resins, Plant/chemistry , Terpenes , Antitubercular Agents/chemistry , Antitubercular Agents/pharmacology , Humans , THP-1 Cells , Terpenes/chemistry , Terpenes/pharmacology
9.
Fitoterapia ; 134: 382-388, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30890423

ABSTRACT

Diverse terpenoids including a novel sesquiterpenoidal lactam, commipholactam A (1), and a structurally related new cadinane sesquiterpenoid, commiphorane H (2), a new eudesmane sesquiterpenoid, commiphorane I (4), a new guaiane sesquiterpenoid, commiphorane J (5), and two new nor-abietane diterpenoids, commiphoranes K1 and K2 (6 and 7) along with two known terpenoids (3 and 8), were isolated from Resina Commiphora. Their structures with absolute configurations were characterized by spectroscopic methods and calculated electronic circular dichroism (ECD). Notably, commipholactam A represents the first example of cadinane sesquiterpene alkaloids isolated from Resina Commiphora. Biological assessment toward human cancer cells showed that the IC50 values of 1 against HepG2 and A549 cells were 21.73 µM and 128.50 µM, respectively.


Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Commiphora/chemistry , Sesquiterpenes/pharmacology , A549 Cells , Abietanes/isolation & purification , Abietanes/pharmacology , Antineoplastic Agents, Phytogenic/isolation & purification , China , Hep G2 Cells , Humans , Molecular Structure , Phytochemicals/isolation & purification , Phytochemicals/pharmacology , Polycyclic Sesquiterpenes , Sesquiterpenes/isolation & purification , Sesquiterpenes, Guaiane/isolation & purification , Sesquiterpenes, Guaiane/pharmacology , Terpenes/isolation & purification , Terpenes/pharmacology
10.
Molecules ; 25(1)2019 Dec 31.
Article in English | MEDLINE | ID: mdl-31906049

ABSTRACT

Five new meroterpenoids, zizhines P-S and U (1-4,7), together with two known meroterpenoids (5 and 6) were isolated from Ganoderma sinensis. Their structures including absolute configurations were assigned by using spectroscopic, computational, and chemical methods. Racemics zizhines P and Q were purified by HPLC on chiral phase. Biological evaluation found that 4, 5 and 6 are cytotoxic toward human cancer cells (A549, BGC-823, Kyse30) with IC50 values in the range of 63.43-80.83 µM towards A549, 59.2 ± 2.73 µM and 64.25 ± 0.37 µM towards BGC-823, 76.28 ± 1.93 µM and 85.42 ± 2.82 µM towards Kyse30.


Subject(s)
Ganoderma/chemistry , Terpenes/chemistry , A549 Cells , Antineoplastic Agents/chemistry , Antineoplastic Agents/isolation & purification , Antineoplastic Agents/pharmacology , Cell Line, Tumor , Cell Survival/drug effects , Fibroblasts/drug effects , Humans , Molecular Structure , Terpenes/isolation & purification , Terpenes/pharmacology
11.
RSC Adv ; 9(38): 22011-22016, 2019 Jul 11.
Article in English | MEDLINE | ID: mdl-35518883

ABSTRACT

Lonimacranaldes A and B (1 and 2), along with one biogenetically related intermediate, lonimacranalde C (3), were isolated from the flower buds of Lonicera macranthoides. Characterized by an iridoid structure and an additional C-6 unit with an aldehyde group, compounds 1 and 2 are the first examples of hybrid iridoids possessing an unexpected 6/5/6 fused tricyclic ring system, while compound 3 serves as an important precursor for their generation. The structures of lonimacranaldes A-C (1-3) were revealed by extensive spectroscopic and X-ray diffraction analyses. A plausible biogenetic pathway for them was proposed. Compound 3 showed anti-inflammatory activities by inhibiting the production of IL-6 on LPS-induced RAW 264.7 cells with an IC50 value of 6.33 µM.

12.
Molecules ; 23(12)2018 Dec 07.
Article in English | MEDLINE | ID: mdl-30544580

ABSTRACT

A novel sesquiterpene dimer, spirocommiphorfuran A (1); two new cadinane sesquiterpenoids, commiphorenes A (2) and B (3); along with three known terpenoids (4⁻6), were isolated from Resina Commiphora. The structures of these new compounds were characterized by NMR, HRESIMS, quantum chemical computation, and X-ray diffraction analysis. Compound 1 features a 7-oxabicyclo[2.2.1]heptane-2-ene core, representing the first example of germacrane-type sesquiterpene dimer fused via a spiro ring system. Compound 2 is a novel sesquiterpene with a completely new carbon skeleton, which is characteristic of an additional carbon attaching to the cadinane backbone via a carbon⁻carbon bond. Additionally, compounds 2 and 4 exert acceptable cytotoxicity toward normal cells and high selectivity in cancer cells, especially in HepG2 cells.


Subject(s)
Burseraceae/chemistry , Terpenes/pharmacology , Carbon-13 Magnetic Resonance Spectroscopy , Cell Death/drug effects , Cell Line, Tumor , Circular Dichroism , Humans , Inhibitory Concentration 50 , Proton Magnetic Resonance Spectroscopy , Terpenes/chemistry
13.
Org Lett ; 20(17): 5506-5509, 2018 09 07.
Article in English | MEDLINE | ID: mdl-30153033

ABSTRACT

Belamchinanes A-D (1-4), four triterpenoids with an unprecedented skeleton, were isolated from the seeds of Belamcanda chinensis and fully characterized. The structures of belamchinanes feature a 4/6/6/6/5 polycyclic system in which a four-membered carbocyclic ring bridges the C-1 and C-11 positions of a classical triterpenoid framework. A plausible pathway for the biosynthesis of 1-4 is proposed. Biological studies reveal that 1-4 dose-dependently protect age-related renal fibrosis in vitro .


Subject(s)
Aging , Carbon/chemistry , Iris/chemistry , Kidney/drug effects , Kidney/pathology , Triterpenes/chemistry , Triterpenes/pharmacology , Fibrosis , Models, Molecular , Molecular Conformation
14.
Org Lett ; 20(18): 5813-5816, 2018 09 21.
Article in English | MEDLINE | ID: mdl-30156853

ABSTRACT

Three unusual sesquiterpenoid dimers, nardochinoids A-C (1-3), were isolated from Nardostachys chinensis Batal. Compound 1 features a rare fused 3,8-dioxatricyclo[7.2.1.01,6]dodecane-11-one ring system, compound 2 is the first nitrogen-containing nornardosinane-aristolane sesquiterpene conjugate, and compound 3 represents the first example of the dimer of a nornardosinane and a nardosinane sesquiterpene. Their structures were characterized by NMR spectroscopic methods and X-ray single-crystal diffraction analysis. Compound 3 showed significant anti-inflammatory activities.

15.
Org Lett ; 20(2): 453-456, 2018 01 19.
Article in English | MEDLINE | ID: mdl-29300490

ABSTRACT

Arteannoide A (1), an unusual cadinane dimer featuring a rare fused 6,8-dioxabicyclo[3.2.l]octan-7-one ring system, arteannoides B and C (2 and 3), two novel heterodimers incorporating a rearranged cadinene sesquiterpenoid and a phenylpropanoid, together with two new rearranged cadinene sesquiterpenoids 4 and 5, were isolated from Artemisia annua L. Their structures were determined by a combination of NMR spectroscopy, electronic circular dichroism calculations, and X-ray diffraction analyses. Compounds 2 and 3 showed inhibition of nitric oxide production in lipopolysaccharide-induced RAW 264.7 mouse macrophage cell lines with IC50 values of 4.5 and 2.9 µM, respectively.


Subject(s)
Artemisia annua , Animals , Cell Line , Lipopolysaccharides , Mice , Molecular Structure , Nitric Oxide , Polycyclic Sesquiterpenes , Sesquiterpenes
16.
PLoS One ; 11(3): e0151147, 2016.
Article in English | MEDLINE | ID: mdl-26954017

ABSTRACT

Decline of cognitive function is the hallmark of Alzheimer's disease (AD), regardless of the pathological mechanism. Traditional Chinese medicine has been used to combat cognitive impairments and has been shown to improve learning and memory. Radix Polygalae (RAPO) is a typical and widely used herbal medicine. In this study, we aimed to follow the ß-amyloid (Aß) reduction activity to identify active constituent(s) of RAPO. We found that Onjisaponin B of RAPO functioned as RAPO to suppress Aß production without direct inhibition of ß-site amyloid precursor protein cleaving enzyme 1 (BACE1) and γ-secretase activities. Our mechanistic study showed that Onjisaponin B promoted the degradation of amyloid precursor protein (APP). Further, oral administration of Onjisaponin B ameliorated Aß pathology and behavioral defects in APP/PS1 mice. Taken together, our results indicate that Onjisaponin B is effective against AD, providing a new therapeutic agent for further drug discovery.


Subject(s)
Amyloid beta-Peptides/biosynthesis , Cognition Disorders/metabolism , Drugs, Chinese Herbal/pharmacology , Medicine, Chinese Traditional , Nootropic Agents/pharmacology , Saponins/pharmacology , Triterpenes/pharmacology , Alzheimer Disease/drug therapy , Alzheimer Disease/metabolism , Alzheimer Disease/physiopathology , Amyloid Precursor Protein Secretases/metabolism , Animals , Aspartic Acid Endopeptidases/metabolism , Cell Line , Cognition Disorders/drug therapy , Disease Models, Animal , Enzyme Activation/drug effects , Humans , Mice , Mice, Transgenic , Proteolysis/drug effects , Substrate Specificity
17.
Molecules ; 19(12): 20880-7, 2014 Dec 12.
Article in English | MEDLINE | ID: mdl-25514227

ABSTRACT

Two new coumarins, talacoumarins A (1) and B (2), were isolated from the ethyl acetate extract of the wetland soil-derived fungus Talaromyces flavus BYD07-13. Their structures were elucidated by spectroscopic data (NMR, MS) analyses. The absolute configuration of C-12 in 1 was assigned using the modified Mosher's method, whereas that of C-12 in 2 was deduced via the circular dichroism data of its corresponding [Rh2(OCOCF3)4] complex. Compounds 1 and 2 were evaluated for their anti-Aß42 aggregation, cytotoxic, and antimicrobial activities. The results showed that the two compounds had moderate anti-Aß42 aggregation activity, and this is the first report on the Aß42 inhibitory aggregation activity of coumarins.


Subject(s)
Coumarins/chemistry , Talaromyces/chemistry , Amyloid beta-Peptides/chemistry , Aspergillus niger/drug effects , Candida albicans/drug effects , Cell Line, Tumor , Cell Survival , Coumarins/isolation & purification , Coumarins/pharmacology , Escherichia coli/drug effects , Humans , Inhibitory Concentration 50 , Microbial Sensitivity Tests , Molecular Structure , Peptide Fragments/chemistry , Protein Aggregates , Staphylococcus aureus/drug effects
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