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Study of the Effectiveness of Papaver Sp. Alkaloids as Future Therapeutic Alternatives against Enterococcus Sp. Causing Hospital-Acquired Septicemic Infections
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作者 Lama Mohammed Ayoub Shbibe Georgette Antranik Babojian 《Journal of Biosciences and Medicines》 2024年第8期107-127,共21页
Background and Objective: In recent years, control of Enterococcus sp. It has been proven in the local medical environment to be a cause of acquired septicemia in various age groups, and medical instruments are consid... Background and Objective: In recent years, control of Enterococcus sp. It has been proven in the local medical environment to be a cause of acquired septicemia in various age groups, and medical instruments are considered an effective means of transmitting enterococcal septicemia, and catheters are at the forefront in terms of danger. Based on this risk, this study aimed to monitor the spread of Enterococcus sp., which causes blood poisoning acquired from catheters, and to compare its response to antibiotics with that of those isolated from clinical samples in children, as a first study locally. The effectiveness of alkaloids of different types of Papaver sp. In Syrian plants, they were tested against infection with this bacteria. Materials and Methods: The study dealt with two parts: The first part included collecting clinical samples from the University Children’s Hospital in Damascus/bacterial diagnostic laboratories/then isolating and diagnosing the bacteria by following a set of tests to identify the most prevalent genera and species and comparing their prevalence rate with Enterococcus. The second part;It included collecting plant samples, confirming the species taxonomically, then extracting alkaloids from plant parts (fruit, stem, Flowers), then comparing the extent of resistance of bacterial strains to antibiotics compared to the Enterococcus sp., and then confirming the antibacterial activity of the Papaver sp. alkaloids against Enterococcus sp. Result:In its first part, the study confirmed the significant contribution of the Enterococcus sp. to infections acquired from various sources, largely in catheter tip infections (9.09%) and to a lesser extent in other sources (3.7%), The second part was to confirm the effective-ness of the alkaloid extract of the Papaver sp., especially the two species Papaver syriacum, and Papaver dubium, against Enterococcus sp. with areole diameters that ranged between (15 - 26 mm) for the fruit extract and at a minimum inhibitory concentration (3.12 - 6.25 mml) and then the stem (5 - 20 mm). And the effectiveness of the Flowers extract is very weak to almost non-existent. Conclusions: The catheter and medical sources surrounding the patient constitute a dangerous source of multi-resistant Enterococcus sp., which poses a real threat to the lives of children, with new mechanisms represented by colonization of the skin and the ability to form biofilms Surfaces of medical instruments, with are resistant to a wide range of antibiotics. As an alternative and effective modern source to limit its spread in the future, the alkaloid extract of the fruits and stems of the wild Papaver sp. has proven a strong antibiotic effect, especially the two types: Papaver syriacum and Papaver dubium. 展开更多
关键词 CATHETERS Skin Ulcers Acquired Infection Multi-Resistant Enterococcus Sp. Papaver Sp. alkaloids Minimum Inhibitory and Lethal Concentration
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Alkaloids as potential antivirals.A comprehensive review 被引量:1
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作者 Shah Faisal Syed Lal Badshah +2 位作者 Bibi Kubra Abdul-Hamid Emwas Mariusz Jaremko 《Natural Products and Bioprospecting》 CSCD 2023年第1期718-755,共38页
Alkaloids are a diverse group of natural phytochemicals.These phytochemicals in plants provide them protection against pests,and herbivorous organisms and also control their development.Numerous of these alkaloids hav... Alkaloids are a diverse group of natural phytochemicals.These phytochemicals in plants provide them protection against pests,and herbivorous organisms and also control their development.Numerous of these alkaloids have a variety of biological effects,and some have even been developed into medications with different medicinal properties.This review aims to provide a broad overview of the numerous naturally occurring alkaloids(isolated from both terrestrial and aquatic species)along with synthetically produced alkaloid compounds having prominent antiviral properties.Previous reviews on this subject have focused on the biological actions of both natural and synthetic alkaloids,but they have not gone into comprehensive detail about their antiviral properties.We reviewed here several antiviral alkaloids that have been described in the literature in different investigational environments i.e.(in-vivo,in-ovo,in-vitro,and in-silico),and found that these alkaloid compounds have significant antiviral properties against several infectious viruses.These alkaloids repressed and targeted various important stages of viral infection at non-toxic doses while some of the alkaloids reported here also exhibited comparable inhibitory activities to commercially used drugs.Overall,these anti-viral effects of alkaloids point to a high degree of specificity,implying that they could serve as effective and safe antiviral medicines if further pursued in medicinal and pharmacological investigations. 展开更多
关键词 alkaloid antivirals Antiviral agents Antiviral phytochemicals In vitro SPREAD Inhibition
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New Neuraminidase Inhibitory Alkaloids from the Mangrove Soil-Derived Fungus Arthrinium sp.SCSIO 41305
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作者 HU Yiwei ZHAO Kai +6 位作者 ZHU Junheng QI Xin CHEN Weihao SONG Yingying PANG Xiaoyan LIU Yonghong WANG Junfeng 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第5期1446-1451,共6页
New alkaloid,(E)-2-(hydroxyimino)-4-methylpentanamide(1)and a new cyclopentano[b]pyridine,4-hydroxy-7-methyl-6,7-dihydro-5H-cyclopenta[c]pyridin-5-one(2),together with ten known compounds(3–12)were isolated from the ... New alkaloid,(E)-2-(hydroxyimino)-4-methylpentanamide(1)and a new cyclopentano[b]pyridine,4-hydroxy-7-methyl-6,7-dihydro-5H-cyclopenta[c]pyridin-5-one(2),together with ten known compounds(3–12)were isolated from the mangrove soil-derived fungus Arthrinium sp.SCSIO 41305.Extensive spectroscopic analysis and X-Ray crystallographic analysis were used to elucidate the structure of(E)-2-(hydroxyimino)-4-methylpentanamide(1),including its absolute configuration.All the isolated compounds(1–12)were evaluated for their antimicrobial and enzyme inhibitory activities against acetylcholinesterase(ACh E),neuraminidase(NAs),and phosphatidylinositol 3-kinase(PI3K).Among them,compounds 1 and 3 exhibited strong neuraminidase inhibitory activity with IC_(50)values of 12.04,1.92μmol L^(-1)(IC_(50)20μmol L^(-1)for oseltamivir acid),while compounds 5,6,8,and 10showed moderate neuraminidase inhibitory activity,and compounds 6–10 displayed weak enzyme inhibitory activities against PI3K. 展开更多
关键词 Arthrinium alkaloid pyridine NEURAMINIDASE ACETYLCHOLINESTERASE
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Anti-inflammatory maistemonine-class alkaloids of Stemona japonica
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作者 Cheng-Yong Tan Bao-Bao Shi +1 位作者 Mei-Fen Bao Xiang-Hai Cai 《Natural Products and Bioprospecting》 CSCD 2023年第1期650-656,共7页
Three hitherto undescribed Stemona alkaloids,named stemajapines A-C(1-3),along with six known alkaloids(4-9),were isolated and identified from the roots of Stemona japonica(Blume)Miq.(Stemonaceae).Their structures wer... Three hitherto undescribed Stemona alkaloids,named stemajapines A-C(1-3),along with six known alkaloids(4-9),were isolated and identified from the roots of Stemona japonica(Blume)Miq.(Stemonaceae).Their structures were established by the analysis of the mass data,NMR spectra,and computational chemistry.Stemjapines A and B were degraded maistemonines without spiro-lactone ring and skeletal methyl from maistemonine.Concurrence of alkaloids 1 and 2 revealed an undescribed way to form diverse Stemona alkaloids.Bioassay results disclosed the anti-inflammatory natural constituents stemjapines A and C with IC_(50) values of 19.7 and 13.8μM,respectively,compared to positive control dexamethasone with 11.7μM.The findings may point out a new direction of Stemona alkaloids inaddition to its traditional antitussive and insecticide activities. 展开更多
关键词 Stemona japonica Stemona alkaloids Stemajapines A-C ANTI-INFLAMMATORY
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Uncarialines A-E,new alkaloids from Uncaria rhynchophylla and their anticoagulant activity
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作者 Ke-Pu Huang Li-Li Xu +5 位作者 Sheng Li Yin-Ling Wei Lian Yang Xiao-Jiang Hao Hong-Ping He Yu Zhang 《Natural Products and Bioprospecting》 CSCD 2023年第1期598-606,共9页
Uncarialines A-E(1-5),five undescribed monoterpene indole alkaloids,together with five known analogues were obtained from the stems of Uncaria rhynchophylla.Alkaloids 1-3 were unique 3,4-seco-tricyclic alkaloids with ... Uncarialines A-E(1-5),five undescribed monoterpene indole alkaloids,together with five known analogues were obtained from the stems of Uncaria rhynchophylla.Alkaloids 1-3 were unique 3,4-seco-tricyclic alkaloids with a 6/5/10 ring system,while 4 and 5 possessed a rare rearranged scaffold originated from corynantheine-type alkaloids with C-2/C-7 oxidation.Their structures were characterized by a comprehensive analysis of MS,NMR,and ECD.Their effects on blood clotting times of human plasma were evaluated and alkaloid 5 had a slight prolongation effect on both thrombin time and activated partial thromboplastin time(p<0.001). 展开更多
关键词 Uncaria rhynchophylla Monoterpene indole alkaloids Uncarialines A-E Anticoagulant activity
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Effects of Different Alkaloids in Coptis chinensis on Inhibiting TGEV Proliferation
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作者 Maixun ZHU Hongmei TANG +3 位作者 Shaoqin ZHAI Lizhi FU Xiaolong DENG Zengjia LIU 《Medicinal Plant》 CAS 2023年第3期15-17,共3页
[Objectives]To study the effects of different alkaloids in Coptis chinensis on inhibiting the proliferation of Transmissible gastroenteritis virus(TGEV).[Methods]The components and content of the main alkaloids in the... [Objectives]To study the effects of different alkaloids in Coptis chinensis on inhibiting the proliferation of Transmissible gastroenteritis virus(TGEV).[Methods]The components and content of the main alkaloids in the extract of C.chinensis were analyzed.The main alkaloids were selected as drugs to inhibit the proliferation of TGEV.The maximum non-toxic concentration of Columbamine,Jatrorrhizine,Epiberberine,Coptisine,Palmatine,and Berberine was screened.The protective rate of each drug on TGEV-infected ST cells was determined,and the transcriptional inhibitory effect of the drug on TGEV N gene was detected by fluorescent quantitative PCR.[Results]The extract of C.chinensis mainly contains 6 alkaloids:Columbamine,Jatrorrhizine,Epiberberine,Coptisine,Palmatine,and Berberine,accounting for 2.03%,8.88%,9.21%,15.07%,14.63%,and 50.18%,respectively.In the range of the safe concentration,Jatrorrhizine,Palmatine,and Coptisine had better protective effects on ST cells infected with TGEV;compared with the Columbamine group,the cell protection rate was significantly different(P<0.05);compared with the Berberine group,the difference was extremely significant(P<0.01).The Coptisine and Palmatine groups had significant inhibitory effects on the transcription of TGEV N gene,and the difference was extremely significant compared with the virus group(P<0.05).[Conclusions]Jatrorrhizine and Palmatine in C.chinensis are the main components to inhibit the proliferation of TGEV. 展开更多
关键词 Extract of Coptis chinensis alkaloids Transmissible gastroenteritis virus(TGEV) ST cells
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Differential accumulation mechanisms of purine alkaloids and catechins in Camellia ptilophylla,a natural theobromine-rich tea
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作者 Chentao Ying Jiawen Chen +4 位作者 Jiahao Chen Peng Zheng Caibi Zhou Binmei Sun Shaoqun Liu 《Beverage Plant Research》 2023年第1期128-136,共9页
Tea is consumed worldwide due to its charming flavor and the refreshing effects conferred by caffeine.Caffeine however has undesirable side effects,such as sleep disturbance.Camellia ptilophylla is known for its low c... Tea is consumed worldwide due to its charming flavor and the refreshing effects conferred by caffeine.Caffeine however has undesirable side effects,such as sleep disturbance.Camellia ptilophylla is known for its low caffeine content,and the biosynthesis of purine alkaloids in this species has become a hot topic.In this study,the accumulation of purine alkaloids in a natural C.ptilophylla population(32 plants)was analyzed,and the results showed that 81.25%of this population were caffeine-free,containing only theobromine(TB),while six plants contained both theobromine and caffeine(CAF).RNA-seq analysis of two C.ptilophylla plants with contrasting purine alkaloid contents(TB and CAF)revealed that xanthosine synthesis genes of the SAM cycle and AMP pathway were significantly related to the differential accumulation of purine alkaloids between TB and CAF.The high theobromine content in TB was attributed to the significantly higher expression of TCS-2,TCS-3 and MXMTs and downregulation of the xanthosine degradation pathway in comparison to CAF.Additionally,CsMYB184 was significantly upregulated in TB,opposing the expression pattern of TCS1,but consistent with that of other TCSs and MXMTs.Furthermore,the upregulated expression of catechin biosynthesis genes,F3'H,F3'5'H and SCPLs in TB corresponded to a higher gallocatechin gallate(GCG)content.Overall,these findings provide new insights into the accumulation of theobromine and GCG,which may facilitate the development of tea plant cultivars with low-caffeine or high GCG to meet the diverse demands of consumers. 展开更多
关键词 alkaloids PURINE attributed
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The Clausena lansium genome provides new insights into alkaloid diversity and the evolution of the methyltransferase family
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作者 Yongzan Wei Yi Wang +9 位作者 Fuchu Hu Wei Wang Changbin Wei Bingqiang Xu Liqin Liu Huayang Li Can Wang Hongna Zhang Zhenchang Liang Jianghui Xie 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第10期3537-3553,共17页
Wampee(Clausena lansium)is an important evergreen fruit tree native to southern China that has a long history of use for medicinal purposes.Here,a chromosome-level genome of C.lansium was constructed with a genome siz... Wampee(Clausena lansium)is an important evergreen fruit tree native to southern China that has a long history of use for medicinal purposes.Here,a chromosome-level genome of C.lansium was constructed with a genome size of 282.9 Mb and scaffold N50 of 30.75 Mb.The assembled genome contains 48.70%repetitive elements and 24,381 protein-coding genes.Comparative genomic analysis showed that C.lansium diverged from Aurantioideae 15.91-24.95 million years ago.Additionally,some expansive and specific gene families related to methyltransferase activity and S-adenosylmethionine-dependent methyltransferase activity were also identified.Further analysis indicated that N-methyltransferase(NMT)is mainly involved in alkaloid biosynthesis and O-methyltransferase(OMT)participates in the regulation of coumarin accumulation in wampee.This suggested that wampee's richness in alkaloids and coumarins might be due to the gene expansions of NMT and OMT.The tandem repeat event was one of the major reasons for the NMT expansion.Hence,the reference genome of C.lansium will facilitate the identification of some useful medicinal compounds from wampee resources and reveal their biosynthetic pathways. 展开更多
关键词 Clausena lansium GENOME EVOLUTION methyltransferase activity alkaloid biosynthesis coumarin accumulation
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Identification and Molecular Characterization of the Alkaloid Biosynthesis Gene Family in Dendrobium catenatum
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作者 Liping Yang Xin Wan +1 位作者 Runyang Zhou Yingdan Yuan 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第1期81-96,共16页
As one of the main active components of Dendrobium catenatum, alkaloids have high medicinal value. The physicochemicalproperties, conserved domains and motifs, phylogenetic analysis, and cis-acting elements of the gen... As one of the main active components of Dendrobium catenatum, alkaloids have high medicinal value. The physicochemicalproperties, conserved domains and motifs, phylogenetic analysis, and cis-acting elements of the genefamily members in the alkaloid biosynthesis pathway of D. catenatum were analyzed by bioinformatics, and theexpression of the genes in different years and tissues was analyzed by qRT-PCR. There are 16 gene families,including 25 genes, in the D. catenatum alkaloid biosynthesis pathway. The analysis of conserved domains andmotifs showed that the types, quantities, and orders of domains and motifs were similar among members ofthe same family, but there were significant differences among families. Phylogenetic analysis indicated that thegene family members showed some evolutionary conservation. Cis-acting element analysis revealed that therewere a large number of light-responsive elements and MYB (v-myb avian myeloblastosis viral oncogene homolog)-related elements in these genes. qRT-PCR showed that expressions of gene family members involved in alkaloidsynthesis were different in different years and tissues of D. catenatum. This study provides a theoretical basisfor further exploration of the regulatory mechanisms of these genes in the alkaloid biosynthesis of D. catenatum. 展开更多
关键词 Dendrobium catenatum gene family alkaloid biosynthesis
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Synergistic effect of pinellia total alkaloids and uncaria total alkaloids on anticonvulsant action in mice and rats 被引量:11
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作者 成银霞 王明正 +5 位作者 陈靖京 杨蓉 何欣嘏 马永刚 杨李华 张明升 《Journal of Chinese Pharmaceutical Sciences》 CAS 2007年第2期139-145,共7页
Aim To investigate the synergistic effect of the combination of pinellia total alkaloid (PTA) and uncaria total alkaloid (UTA), and explore the mechanism of anticonvulsant action. Methods Anticonvulsant and toxic ... Aim To investigate the synergistic effect of the combination of pinellia total alkaloid (PTA) and uncaria total alkaloid (UTA), and explore the mechanism of anticonvulsant action. Methods Anticonvulsant and toxic effect profiles of combinations of PTA with UTA, alone and at three fixed ratios of 1:4, 1 :1, 4:1, were evaluated in maximal electroshock (MES)-induced seizures and acute toxicity test in mice. Respective ED50 and LD50 were calculated with Bliss's method. Their synergistic effect were evaluated by isobolographic analysis and allowed the determination of benefit indices (BI) for respective combinations. The model of convulsive rats kindled by penicillin topically injected into cortex was used to investigated the content of Glu, Asp, Gly and GABA in hippocampus using high performance liquid chromatography (HPLC). Results Combinations of PTA and UTA at the ratio of 4:1 were synergistic in MES test and antagonistic in acute toxicity test, showing the best profile for combinations of PTA with UTA. In contrast, the ratios of 1 :4 and 1 : 1, despite synergistic in MES test, were additive in acute toxicity test. The 4:1 combination and two drugs alone significantly decreased Glu level and increased GABA level in the hippocampus, but the GABA level in the 4:1 combination group was higher than that in the two drugs alone groups. They did not have significant influence on the levels of ASp and Gly. Conclusion Combinations of PTA and UTA at 4:1 ratio demonstrated synergistic effect in anticonvulsant action and antagonistic effect in toxicity. The anticonvulsant mechanism might be related to decreasing the excitability of Glutamatergic neurons and increasing the inhibition of GABAergic neurons. 展开更多
关键词 Pinellia total alkaloids Uncaria total alkaloids Synergistic effect Anticonvulsant action Isobolographic analysis Maximal electroshock Penicillin kindling NEUROTRANSMITTERS
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Two Novel Hydroperoxylated Lycopodium Alkaloids from Huperzia serrata 被引量:3
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作者 谭昌恒 马晓强 +2 位作者 周慧 蒋山好 朱大元 《Acta Botanica Sinica》 CSCD 2003年第1期118-121,共4页
Two novel hydroperoxylated Lycopodium alkaloids, 11alpha-hydroperoxyphlegmariurine B (1) and 7-hydroperoxyphlegmariurine B (2), along with a known compound, phlegmanurine B (3), were isolated from the total alkaloid f... Two novel hydroperoxylated Lycopodium alkaloids, 11alpha-hydroperoxyphlegmariurine B (1) and 7-hydroperoxyphlegmariurine B (2), along with a known compound, phlegmanurine B (3), were isolated from the total alkaloid fraction of the Chinese medicinal herb Huperzia serrata (Thunb.) Trev. Their structures and relative configurations were elucidated on the basis of spectroscopic analyses. 展开更多
关键词 Huperzia serrata Lycopodium alkaloids 11 alpha-hydroperoxyphlegmariurine B 7-hydroperoxyphlegmaniurine B
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Isolation and Identification of Eleven Tertiary Alkaloidsin Corydalis decumbens 被引量:10
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作者 廖静 梁文藻 涂国士 《Journal of Chinese Pharmaceutical Sciences》 CAS 1995年第2期57-61,共5页
Eleven tertiarv alkaloids were isolated from Corvdalis decumbens rhizome Their structures were identified as protopine(Ⅶ),allocryptopine(Ⅷ),cryptopine (Ⅸ),muramine(ⅩⅦ);(+)-tetrahydropalmatine(Ⅲ),(+)-kikemanine (... Eleven tertiarv alkaloids were isolated from Corvdalis decumbens rhizome Their structures were identified as protopine(Ⅶ),allocryptopine(Ⅷ),cryptopine (Ⅸ),muramine(ⅩⅦ);(+)-tetrahydropalmatine(Ⅲ),(+)-kikemanine (Ⅳ),(一)-scoulerine (ⅩⅧ),(十)-bulbo- capnine (ⅩⅨ),and(一)一capnoidine(Ⅰ),(一)一bicuculline(Ⅴ),(+) coriumidine(ⅩⅣ), respecti vely。 Among these,cryptopine,muramine,(+)-kikemanine,(-)-scoulerine,(一)capnoidine,(一)一bicuculline were isolated for the first time from this plant 展开更多
关键词 Corydalis deculnbeng Tertiary alkaloids (+)-kikemanine (-)-scoulerine Mu- ramine
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Insecticidal Activities of Alkaloids Extracted from Poisonous Plants
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作者 刘海峰 全炳武 李翔国 《Plant Diseases and Pests》 CAS 2010年第6期64-67,共4页
[Objective] Insecticidal activities of alkaloids extracted from 12 poisonous plants in Changbai Mountain were studied in the paper,to provide the basis for development and utilization of poisonous plants in Changbai M... [Objective] Insecticidal activities of alkaloids extracted from 12 poisonous plants in Changbai Mountain were studied in the paper,to provide the basis for development and utilization of poisonous plants in Changbai Mountain.[Method] Leaf disc method was used to study the effects of alkaloids extracted from 12 poisonous plants on the growth and development of 3-5 instars of cabbage worm (Pieris rapae) and their antifeedant activities.[Result] The effects of alkaloids extracted from different poisonous plants on the growth and development of cabbage worm were also different.Five treatments of alkaloids extracted from Sophora flavescens,Datura stramonium L.,Arisaema amurense Maxim.,Veratum dahuricum Loes.and Tripterygium regelii Spragne et Takeda made the weight of test insects gradually decrease and finally die;the alkaloid treatments of Pueraria lobata (Willd.) Ohwi,Aconitum kusnezoffii Reichb.,Cimicifuga dahurica (Turcz.) Maxim.and Corydalis ambigua Schleeht.could make cabbage worm pupate ahead of time,but the pupa state was deformed;the antifeedant rates of cabbage worm after the treatments of P.lobata,A.kusnezoffii,C.dahurica,A.amurense,V.dahuricum and C.ambigua for 48 h were all over 90%,and the antifeedant rates of C.dahurica and C.ambigua were the highest as 100%.[Conclusion]The reports on the insecticidal activities of five poisonous plants including P.lobata,A.kusnezoffii,C.dahurica,C.ambigua and A.amurense are rare,and they have important values on the development of botanical pesticides. 展开更多
关键词 Poisonous plant alkaloid Insecticidal activity Antifeedant rate
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Norditerpenoid Alkaloids from Delphinium orthocentrum (Ranunculaceae)
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作者 丁立生 王静 +1 位作者 彭树林 陈能煜 《Acta Botanica Sinica》 CSCD 2000年第5期523-525,共3页
Two new norditerpenoid alkaloids, orthocentrine (1) and deacetylswinanine A (2), together with a known alkaloid, swinanine A (3), were isolated from the whole plants of Delphinium orthocentrum Franch. The structures o... Two new norditerpenoid alkaloids, orthocentrine (1) and deacetylswinanine A (2), together with a known alkaloid, swinanine A (3), were isolated from the whole plants of Delphinium orthocentrum Franch. The structures of the new alkaloids (1 and 2) were elucidated as 7,10_dihydroxy_8,14,16_trimethoxy_19,20_didehydro_aconitane (7β,8β,14α,16β) (1) and 20_ethyl_2,3_didehydro_6,10_dihydroxy_7,8_methylenedioxy_1,14,16_trimethoxy_aconitane (1α,6β,14α,16β) (2) by spectroscopic evidence and chemical transformation. 展开更多
关键词 Delphinium orthocentrum RANUNCULACEAE norditerpenoid alkaloids orthocentrine deacetylswinanine A
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The Alkaloids from Leaves of Croton hemiargyerius var. gymnodiscus
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作者 林文翰 付宏征 +2 位作者 李军 程刚 Roderick A.Barnes 《Journal of Chinese Pharmaceutical Sciences》 CAS 2003年第3期117-122,共6页
Aim Investigation of alkaloids from the leaves of Brazilian medicinal plantCroton hemiargyerius var. gymnodiscus. Methods Silica gel column chromatography was used repeatedlyfor the isolation and purification, and the... Aim Investigation of alkaloids from the leaves of Brazilian medicinal plantCroton hemiargyerius var. gymnodiscus. Methods Silica gel column chromatography was used repeatedlyfor the isolation and purification, and their structures were identified by extensive spectroscopyand comparison of the chemical and physical data with those of authentic samples reported inliterature. Results Twelve alkaloids were isolated and their structures were identified. ConclusionFour new alkaloids named hemiargines A (1), B (5), C (6) and D (7), together with eight knownalkaloids namely isoc-orydine (2), corydine (3), norcorydine (4), salutaridine (8), glaucine (9),tetrahydropalmatrubine (10), xylopinoine (11), and norlaudanosine (12) were isolated. 展开更多
关键词 csroton hemiargyerius new alkaloids hemiargines A B C D
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Abnormal Secondary Growth and Histochemical Localization of Alkaloids in Root System of Aconitum flavum Hand.-Mazz.
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作者 祁建钊 郭继元 徐青 《Agricultural Science & Technology》 CAS 2011年第9期1313-1317,共5页
[Objective] The purpose of this study was to clarify the structure,growth pattern and histochemical localization of alkaloids in root system of Aconitum flavum Hand.-Mazz.[Method] Paraffin sectioning and histochemistr... [Objective] The purpose of this study was to clarify the structure,growth pattern and histochemical localization of alkaloids in root system of Aconitum flavum Hand.-Mazz.[Method] Paraffin sectioning and histochemistry were employed for performing the analysis in this study.[Result] The root system of Aconitum flavum Hand.-Mazz.consists of taproot,lateral root and adventitious root.The primary structure of root system is normal,but secondary structure shows abnormal.The cambium and the extra cambium of taproot form a "U"-shaped secondary vascular bundle and tertiary bundle in abnormal secondary structure.The sieve tube group is made of little sieve tube group which is differentiated from primary phloem and cambium.Meanwhile,the secondary xylem in tuberous root also appears to be a "U" shape.Parenchyma cells of secondary phloem occupy most of the tuberous root.The sieve tube group of tuberous root is mainly differentiated from parenchyma cell of secondary phloem.[Conclusion] The difference in abnormal secondary structure of taproot and tuberous root are attributed to their varied cambium compose and activity pattern.Alkaloids are mainly accumulated in parenchyma cell of the inside cortex and between bundle in taproot,while parenchyma of secondary phloem and pith in tuberous root. 展开更多
关键词 Aconitum flavum Hand. - Mazz. Root system Abnormal secondary growth alkaloids Histochemical localization
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Rapid analysis and identification for the alkaloids from Ranunculus japonicus by UPLC /Q-TOF-MS
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作者 钟艳梅 冯毅凡 谭毓治 《Journal of Measurement Science and Instrumentation》 CAS 2014年第3期87-93,共7页
To establish a rapid and effective method for analysis and identification of the alkaloids from Ranunculus japoni- cus Thunb by ultra-performance liquid chromatogaraphy with quadruple-time-of-flight mass spectrometry ... To establish a rapid and effective method for analysis and identification of the alkaloids from Ranunculus japoni- cus Thunb by ultra-performance liquid chromatogaraphy with quadruple-time-of-flight mass spectrometry (UPLC/Q-TOF- MS) and discuss their fragmentation regularity, the UPLC/Q-TOF-MS was used to identify the alkaloids from Ranunculus japonicus Thunb by their MS data, tandem characteristic fragment ions and standards. In the end, 12 alkaloids were identi- fied from Ranunculus japonicus for the first time, and their fragmentation regularity was discussed. Thus, a rapid and effec- tive analysis and identification method for the alkaloids from Ranunculus japonicus by UPLC/Q-TOF-MS is established. 展开更多
关键词 alkaloids ultra-performance liquid chromatogaraphy with quadruple-time-of-flight mass spectrometry (UPLC/Q-TOF-MS) Ranunculus japonicas
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Antitumor Alkaloids Isolated from Tylophora ovata 被引量:9
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作者 甄月英 黄学石 +1 位作者 于德泉 庾石山 《Acta Botanica Sinica》 CSCD 2002年第3期349-353,共5页
Four phenanthroindolizidine alkaloids, named tylophoridicine A (1), tylophorinine (2), O_methyl tylophorinidine (3) and tylophorinidine (4), were isolated from the roots of Tylophora ovata (Lindl.) Hook. ex Steud.... Four phenanthroindolizidine alkaloids, named tylophoridicine A (1), tylophorinine (2), O_methyl tylophorinidine (3) and tylophorinidine (4), were isolated from the roots of Tylophora ovata (Lindl.) Hook. ex Steud. Using modern NMR techniques including NOESY and 1H_NMR line broadening effect experiments, CD spectra and MS analysis as well as chemical methods, their structures were identified as (13aR)_6_hydroxy_3,7_dimethoxy_phenanthroindolizidine (1), (13aS,14R)_14_hydroxy_3,6,7_trimethoxy_phenanthro_indolizidine (2), (13aS,14S)_14_hydroxy_3,6,7_trimethoxy_phenanthroindolizidine (3), and (13aS,14S)_6,14_dihydroxy_3,7_dimethoxy_phenanthroindolizidine (4) respectively. Compound 1 is a new compound, compounds 2-4 are obtained from this plant for the first time. Compounds 1, 3 and 4 showed strong antitumor activities. 展开更多
关键词 Tylophora ovata phenanthroindolizidine alkaloid tylophoridicine A tylophorinine O_methyl tylophorinidine tylophorinidine ANTITUMOR
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Determination of the Content of Total Alkaloids in Different Solvent Extracts from Climbing Groundsel Herb Produced in Guizhou Province and Their Antibacterial Activity 被引量:3
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作者 饶海 周镁 +2 位作者 秦拴梅 黄秀平 覃容贵 《Agricultural Science & Technology》 CAS 2013年第10期1417-1420,1428,共5页
[Objective] This study aimed to compare the contents of total alkaloids in different solvent extracts from climbing groundsel herb produced in Guizhou Province and their antibacterial activity. [Method] The content of... [Objective] This study aimed to compare the contents of total alkaloids in different solvent extracts from climbing groundsel herb produced in Guizhou Province and their antibacterial activity. [Method] The content of total alkaloids was measured by UV spectrophotometry, and Oxford cups were used to investigate the antibacterial activity of each solvent extract. [Result] There was a good linear correlation between the absorbance measured by the UV spectrophotometer and the content of total al- kaloids within the concentration of 0.011 0-0.054 8 mg/ml at 207 nm, and the re- gression equation was Y=23.654X+0.021, R=0. 999 7 and the average recovery rate was 99.2%. The contents of total alkaloids in 60% ethanol extract, 95% ethanol and water ethanol were 38.71, 52.25 and 60.50 mg/g, respectively. The 60% ethanol ex- tract had strong antibacterial activity against Streptococcus pneumoniae, Staphylo- coccus aureus and Escherichia coil; the water extractive had stronger antibacterial activity against Escherichia colr, 95% ethanol extract had weak antibacterial activity, with no inhibition of Pseudomonas aeruginosa. [Conclusion] This method is accurate, simple, with good repeatability, which can be used for the determination of alkaloids content of the climbing groundsel herb; there is no positive correlation between the content of total alkaloids in different solvent extracts of climbing groundsel herb and their antibacterial activity. 展开更多
关键词 Climbing groundsel herb (Senecio scandens Buch.-Ham) Total alkaloids Ultraviolet spectrophotometry Antibacterial activity
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Effect of processing on the alkaloids in Aconitum tubers by HPLC-TOF/MS 被引量:11
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作者 Min Liu Yan Cao +4 位作者 Diya Lv Wen Zhang Zhenyu Zhu Hai Zhang Yifeng Chai 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2017年第3期170-175,共6页
According to the Chinese Pharmacopoeia 2015, only processed Aconitum tubers can be clinically applied, and the effect of processing is unclear. This research aimed to explore the effect of processing on cardiac effica... According to the Chinese Pharmacopoeia 2015, only processed Aconitum tubers can be clinically applied, and the effect of processing is unclear. This research aimed to explore the effect of processing on cardiac efficacy of alkaloids in Aconitum tubers. First, the chemical ingredients in unprocessed and processed Aconitum tubers were identified and compared by using high performance liquid chromatography time-of-flight mass spectrometry(HPLC-TOF/MS) and multivariate pattern recognition methods. Then the representative alkaloids in Aconitum tubers, aconitine, benzoylaconine, and aconine, which belong to diester-diterpenoid alkaloids,monoester-diterpenoid alkaloids, and amine-diterpenoid alkaloids, respectively, were selected for further validation of attenuated mechanism. Subsequent pharmacological experiments with aconitine, benzoylaconine,and aconine in SD rats were used to validate the effect of processing on cardiac functions. After processing the Aconitum tubers, it was found that the contents of diester-diterpenoid alkaloids were reduced, and those of monoester-diterpenoid alkaloids and amine-diterpenoid alkaloids were increased, suggesting that diesterditerpenoid alkaloids were transformed into monoester-diterpenoid alkaloids and amine-diterpenoid alkaloids.Through further decocting the aconitine in boiling water, it was confirmed that the three alkaloids could be progressively transformed. Pharmacological experiments with aconitine, benzoylaconine, and aconine in SD rats showed that aconitine at a dose of 0.01 mg/kg and aconine at a dose of 10 mg/kg enhanced the cardiac function, while benzoylaconine at a dose of 2 mg/kg weakened the cardiac function. The effect of processing is attributed to the transformation of the most toxic diester-diterpenoid alkaloids into less toxic monoesterditerpenoid alkaloids and amine-diterpenoid alkaloids. 展开更多
关键词 ACONITUM TUBERS alkaloids PROCESSING HPLC-TOF/MS
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