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1.
A new dihydroagarofuran-based sesquiterpene, 15-acetoxyorbiculin A, was isolated from the root of Microtropis japonica, together with 13 known compounds. Their structures were determined through in-depth spectroscopic and mass-spectrometric analyses. Among the isolated compounds, celahin C and salasol A exhibited potent in vitro antituberculosis activity, both with an MIC value of 15.0 microg/ml against Mycobacterium tuberculosis H(37)Rv.  相似文献   

2.
A new dihydroagarofuran-based sesquiterpene, 8-acetoxymutangin (1), was isolated from the stems of Microtropis fokienensis, together with eight known compounds, including mutangin (2). Their structures were determined through in-depth spectroscopic and mass-spectrometric analyses. Among the isolated compounds, 1 exhibited potent in vitro antituberculosis activity, with an MIC value of 10.0 microg/ml against Mycobacterium tuberculosis 90-221387, which is considerably better than that of mutangin (2). The activity of 1 lies in the same range as that of the clinic drug ethambutol (MIC 6.25 microg/ml), despite completely different chemical structures, which indicates different modes of action.  相似文献   

3.
A new indole alkaloid, 11,12-dimethoxyhenningsamine, was isolated from the roots of Strychnos cathayensis, together with 19 known compounds. The structure of this new compound was determined through spectroscopic and mass-spectrometric analyses. Among the isolated compounds, 11-methoxyhenningsamine and aesculetin dimethyl ether exhibited potent inhibition (IC(50) < 5.5 microg/ml) on superoxide-anion generation and elastase release by human neutrophils in response to fMet-Leu-Phe/cytochalasin B.  相似文献   

4.
【目的】探究药用昆虫喙尾琵琶甲Blaps rynchopetera肠道具有抗菌活性的放线菌,为抗菌药物开发提供新的放线菌资源。【方法】结合稀释涂布法和选择培养法从喙尾琵琶甲成虫肠道分离放线菌。以耐甲氧西林金黄色葡萄球菌(methieillin-resistant Staphylococus aureus)、金黄色葡萄球菌、大肠杆菌Escherichia coli、粪肠球菌Enterococcus faecalis、鼠伤寒沙门氏菌Salmonella typhimurium 和铜绿假单胞菌Pseudomonas aeruginosa 6株致病细菌以及黑曲霉Aspergillus niger、青霉菌Penicillium expansum和白色念珠菌Canidia albicans 3株致病真菌为指示菌,通过牛津杯琼脂扩散法测试放线菌次生代谢产物的抗菌活性。随后,采用分子生物学方法进行16S rRNA序列分析鉴定活性显著的18株放线菌并构建系统发育树。【结果】从喙尾琵琶甲成虫肠道中分离到176株共生放线菌,初步活性筛选结果显示其中46株放线菌表现出不同程度的抗菌活性。多株放线菌对致病菌具有广谱的抑菌作用且抑菌圈直径超过阳性对照药。选择抑菌圈直径大于15 mm的18株放线菌进行分子鉴定,结果显示均为链霉属Streptomyces。【结论】喙尾琵琶甲肠道含有丰富的抗菌活性放线菌资源。  相似文献   

5.
The characteristic pungency of the liverworts Plagiochila species P. fruticosa, P. hattoriana, P. ovalifolia and P. yokogurensis is due to a new ent-secoaromadendrane-type sesquiterpene hemiacetal, plagiochiline A, which exhibits very strong antifeedant activity against the African army worm, Spodoptera exempta at 1–10ng/cm2. Two new secoaromadendranes, plagiochilide and furanoplagiochilal A, together with the previously known plagiochiline C were isolated from P. yokogurensis. Plagiochilal A, which may be a precursor of plagiochilide and its related hemiacetals, and a bitter principle, plagiochiline B were also isolated from P. hattoriana. P. ovalifolia contained plagiochilines A, B and C. From P. fruticosa, plagiochilide and plagiochilines A, B and C were isolated. The structures of the new secoaromadendrane-type sesquiterpenes were elucidated by extensive 1H NMR and 13CNMR studies.  相似文献   

6.
小花老鼠簕(Acanthus ebracteatus)是一种生长在红树生态系统的珍稀真红树植物,具有较高的药用价值。为研究小花老鼠簕内生及根际可培养细菌多样性,挖掘其潜在新物种及具有特殊生物学活性的菌株,该文利用7种不同培养基,通过传统稀释涂布法对小花老鼠簕各植物组织及根际土壤可培养细菌进行分离,基于16S rRNA基因序列解析其内生及根际细菌群落结构和多样性特征,应用植物病原菌平板对峙实验和平铺捕食活性测试分析其可培养细菌的抗菌活性。结果表明:(1)基于16S rRNA基因序列分析,发现从小花老鼠簕的根、茎、叶、花及根际土壤中分离得到144株可培养细菌,这些细菌隶属于18目26科37属66种,芽孢杆菌属(Bacillus)和链霉菌属(Streptomyces)为优势菌属,分别占细菌种数的15.1%和13.6%;(2)拮抗多种植物病原菌试验结果显示,获得29株具有拮抗植物病原菌活性的细菌,10株具有广谱抑菌活性,其中链霉菌属菌株拮抗作用最强且菌株Y129为潜在新物种。(3)捕食活性测试结果显示,有5株细菌对金黄色葡萄球菌(Staphylococcus aureus)、耐甲氧西林金黄色葡...  相似文献   

7.
A new caryophyllene, named pulicaryenne A ( 1 ), along with four other known caryophyllene derivatives ( 2 , 3 , 4 and 5 ) were isolated from the ethyl acetate extract of aerial parts of Pulicaria vulgaris Gaertn . (Asteraceae). All compounds were isolated for the first time from this species. Compound 2 was identified as a new epimer of a known caryophyllene derivative isolated previously from P. dysenterica. Their structures were established by spectroscopic means including NMR analysis (1D‐ and 2D‐NMR) and ESI‐TOF‐MS. All compounds were evaluated for their anticholinesterase, antityrosinase and cytotoxic activities against two human cell lines (A549 and HeLa). Results showed that compound 5 exhibited the highest cytotoxic effect against A549 and anticholinesterase activity with IC50 values of 8.50±0.75 and 6.45±0.09 μg/mL, respectively. Furthermore, compound 5 showed also an interesting antityrosinase activity with percent inhibition value of 79.0±2.5 % at 50 μg/mL. The bioactivity and drug likeness scores of the isolated compounds 1–5 were calculated using Molinspiration software and discussed. These results may suggest that the five caryophyllene derivatives endowed with good biological properties, which could be used as bioactive alternatives in pharmaceutical preparations.  相似文献   

8.
该文采用ODS、硅胶、Sephadex LH-20等柱色谱技术,对柬埔寨野生柯拉斯那沉香(Aquilaria crassna)进行了研究。结果表明:从柬埔寨柯拉斯那所产沉香的乙醇提取物中进行分离共得到了10个化合物,包括一对对映异构体(9a/9b)。经波谱解析分别鉴定为6-甲氧基-2-[2-(3-羟基-4-甲氧基苯)乙基]色酮(1)、6-甲氧基-2-[2-(3-甲氧基-4-羟基苯)乙基]色酮(2)、6,7-二甲氧基-2-(2-苯乙基)色酮(3)、6-羟基-2-(2-苯乙基)色酮(4)、6-羟基-2-[2-(4-甲氧基苯)乙基]色酮(5)、8-氯-6-羟基-2-[2-(3-羟基-4-甲氧基苯)乙基]色酮(6)、8-氯-6-羟基-2-[2-(4-甲氧基苯)乙基]色酮(7)、oxidoagarochromone B(8)、4'-demethoxyaqusisnenone D(9)。其中,化合物6、7和9均为首次从柯拉斯那沉香中分离得到。活性测试结果显示,化合物1和2对乙酰胆碱脂酶具有一定的抑制活性,化合物2对人慢性髓原白血病细胞K562具有较弱的抑制作用。  相似文献   

9.
为了更好的研究毒根斑鸠菊(Vernonia cumingiana Benth)叶茎的化学成分与活性测定,利用硅胶柱层析、Sephadex LH-20等柱色谱技术对毒根斑鸠菊叶茎提取物进行了分离,并采用现代波谱学技术(1 H NMR、13C NMR、HMBC、HMQC等)及X-射线单晶衍射技术并根据其理化性质鉴定了七个化...  相似文献   

10.
Three new 4,5‐seco‐20(10→5)‐abeo‐abietane diterpenoids, 16‐hydroxysalvilenone ( 1 ), 15‐hydroxysalprionin ( 2 ), and 11β,15‐dihydroxysalprionin‐12‐one ( 3 ), and nine known abietane diterpenoids, 4 – 12 , along with one known sempervirane diterpenoid, hispidanol A ( 13 ), were isolated from the aerial parts of Isodon lophanthoides var. graciliflorus. The structures of compounds 1 – 3 were determined on the basis of spectroscopic methods including extensive analysis of NMR and mass spectroscopic data. All diterpenoids were tested for their TNF‐α inhibitory effects on LPS‐induced RAW264.7 cells. Compound 9 (16‐acetoxyhorminone) was the most potent with an IC50 value of 3.97±0.70 μm .  相似文献   

11.
Three new highly brominated polyphenols, 1 – 3 , together with one known bromophenol, 4 , were isolated from the EtOH extract of a marine red alga Symphyocladia latiuscula collected from the coast of Qingdao, P. R. China. Their structures were identified by extensive spectroscopic experiments (NMR and MS) and comparison with literature data. Compounds 3 and 4 showed activities against the Candida albicans with the MIC values of 25 and 12.5 μg/ml, respectively.  相似文献   

12.
A new actinomycete strain designated Sg 10, producing antimicrobial substances was isolated from an Algerian soil. Morphological and chemical studies indicated that strain Sg 10 belonged to the genus Streptosporangium. The comparison of its physiological characteristics with those of known species of Streptosporangium showed significant differences with the nearest species Streptosporangium carneum. Analysis of the 16S rDNA sequence of strain Sg 10 showed a similarity level ranging between 96.3% and 97.8% within Streptosporangium species, with S. carneum the most closely related. However, the phylogenetic analysis indicated that strain Sg 10 represent a distinct phyletic line suggesting a new genomic species. The antimicrobial activity of strain Sg 10 showed an antibacterial activity against Gram-positive bacteria as well as an antifungal one. Four active products were isolated from the culture broth using various separation procedures. On the basis of UV-VIS spectrometry, infrared spectroscopy and chemical revelations, the antibiotics were classified in the group of glycosylated aromatics.  相似文献   

13.
Steroidal glycosides from Cynanchum forrestii Schlechter   总被引:2,自引:0,他引:2  
Liu Y  Hu Y  Yu S  Fu G  Huang X  Fan L 《Steroids》2006,71(1):67-76
Nine new steroidal glycosides, cynaforrosides B, C, D, E, and F, based on a 13, 14: 14, 15-disecopregnane-type skeleton, cynaforrosides G, H, and I with a new aglycone named cynaforrogenin A, and cynaforroside J together with three known C21 steroidal glycosides cynatratoside A, hancoside and komaroside C were isolated from the ethanol extract of the roots of Cynanchum forrestii Schlechter. The structures of new compounds were determined on the basis of spectral and chemical evidence. Steroidal glycosides with three kinds of skeletons were isolated from this plant simultaneously. The sugar units of cynaforrosides B-I contained two moieties of glucoses and especially cynaforrosides E-I contained two glucoses with the mode of 1-->6 linkage, which were rare among steroidal glycosides of the genus Cynanchum.  相似文献   

14.
Four new doramectin congeners, 1-4, were isolated from Streptomyces avermitilis NEAU1069. The structures of 1-4 were elucidated on the basis of spectroscopic analysis, including 1D- and 2D-NMR as well as HR-ESI-MS, ESI-MS, UV, and IR, and comparison with literature data. All compounds exhibited noticeable acaricidal and insecticidal activities. Especially compound 2 was found to be the most potent pesticide of the compounds evaluated with the IC(50) values of 10.2, 65.1 and 124.4 μg/ml against adult two-spotted spider mites (Tetranychus urticae Koch), two-spotted spider mite eggs, and Mythimna separata, respectively, which are comparable to those of commercial pesticide milbemycin A(3)/A(4) as positive reference.  相似文献   

15.
Five new phenylpropanoid glycosides, susaroysides A–E (15) were isolated from the fruits of Forsythia suspensa. Their structures were elucidated by comprehensive spectroscopic data analysis. The absolute configurations of their sugars were determined by GC analysis. Notably, susaroysides A–D possessed a sugar with an unsubstituted anomeric carbon, which is relatively rare in natural sources. Compound 1 exhibited significant anti-inflammatory activity against the lipopolysaccharide (LPS)-induced tumor necrosis factor (TNF)-α expression in macrophage cells with the IC50 value of 1.053 μM.  相似文献   

16.
Piper nigrum finds an extensive application in antibacterial preparations belonging to Ayurvedic system of medicine. A bioguided extraction and fractionation of the petroleum ether extract of the berries of P. nigrum afforded 2E, 4E, 8Z-N-isobutyleicosatrienamide (1), pellitorine (2), trachyone (3), pergumidiene (4) and isopiperolein B (5). Pergumidiene and trachyone are isolated for the first time from P. nigrum. All the isolated compounds were active against Bacillus subtilis, Bacillus sphaericus, and Staphylococcus aureus amongst Gram +ve bacteria, and Klebsiella aerogenes and Chromobacterium violaceum among Gram –ve bacterial strains.  相似文献   

17.
Chen H  Xu N  Zhou Y  Qiao L  Cao J  Yao Y  Hua H  Pei Y 《Steroids》2008,73(6):629-636
Seven new steroidal glycosides (amplexicosides A (4), B (7), C (8), D (9), E (10), F (11), and G (12)), along with six known compounds (cynatratoside A (1), tylophoside A (2), cynatratoside B (3), glaucogenin A (5), glaucoside A (6), and hancoside A (13)) were isolated from the 95% ethanol extract of the roots of Cynanchum amplexicaule (Sieb. et Zucc.). Their structures were determined based on spectral and chemical evidence. Compound 12 has a 14, 15-secopregnane-type skeleton aglycone, which has not been reported in literature.  相似文献   

18.
A new saponin, leucasin, has been isolated from Leucas nutans and characterized on the basis of chemical investigation and spectroscopic studies as 3-O-[β- -glucopyranosyl(1→2)β- -glucopyranosyl]2,3β-dihydroxylup-20(29)-ene. Lupeol palmitate, sitosterol and stigmasterol were also isolated.  相似文献   

19.
A phytochemical investigation of the branches and leaves of Cephalotaxus lanceolata resulted in the isolation of three new cephalotaxus alkaloids, cephalancetines A, B, and D ( 1, 2 , and 4 , resp.), together with ten known alkaloids, 3 and 5 – 13 . The structures of the alkaloids were elucidated on the basis of spectroscopic analyses, including 1D‐ and 2D‐NMR, and HR‐ESI‐MS, and single‐crystal X‐ray diffraction. All isolated compounds were tested for their cytotoxicities against four human tumor cell lines, A549, HCT116, SK‐BR‐3, and HepG2. Compounds 12 and 13 showed remarkable activities against A549, HCT116, and HepG2 cell lines.  相似文献   

20.
药用植物青蒿不同种类的内生菌抑菌活性分析   总被引:1,自引:0,他引:1  
李玲玲 《广西植物》2021,41(7):1112-1119
为了研究青蒿不同种类的内生菌抑制细菌和抑制真菌的活性,该研究采用组织块法和研磨法从青蒿的根、茎、叶中分离内生细菌、放线菌和真菌,以大肠埃希菌(Escherichia coli)(CICC 23657)、枯草芽孢杆菌(Bacillus subtilis)(CICC 10275)、金黄色葡萄球菌(Staphylococcu...  相似文献   

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