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1.
Three racemic butanolides, majorenolide ( 1 ), majorynolide ( 2 ), and majoranolide ( 3 ), with 18 known compounds, including ten butanolides, i.e., litsenolide A2 ( 4 ), litsenolide B2 ( 5 ), litsenolide C1 ( 6 ), litsenolide C2 ( 7 ), hamabiwalactone A ( 8 ), hamabiwalactone B ( 9 ), litseakolide A ( 10 ), litseakolide B ( 11 ), isoobtusilactone ( 12 ), and obtusilactone ( 13 ); one lignan, i.e., (±)‐syringaresinol ( 14 ), two flavans, i.e., (+)‐catechin ( 15 ), and (?)‐epicatechin ( 16 ), one coumarin, i.e., scopoletin ( 17 ), and four steroids, i.e., a mixture of β‐sitosterol ( 18 ) and stigmasterol ( 19 ), and a mixture of β‐sitosteryl‐3‐O‐β‐D ‐glucoside ( 20 ) and stigmasteryl‐3‐O‐β‐D ‐glucoside ( 21 ) were isolated from the root of Lindera akoensis. The structures of the isolates were elucidated by in‐depth spectroscopic analysis. Compounds 1 – 3 were previously assigned a δ‐lactone structure, which was then revised to a γ‐lactone structure, based on 1D‐NMR data. The cigar‐HMBC technique was used to confirm the accuracy of the γ‐lactone structure, and the zero [α] value of compounds 1 – 3 suggested that they were considerably racemized. Nine butanolides 1 – 3, 4 – 8 , and 10 showed antimycobacterial activities against M. tuberculosis H37Rv, with MIC values of 15–50 μg/ml.  相似文献   

2.
3.
Two tropical trees, Acacia confusa and Litsea glutinosa, were grown under controlled conditions with their roots subjected to soil drying and soil compaction treatments. In both species, a decline in stomatal conductance resulting from soil drying took place much earlier than the decline of leaf water potential. Soil compaction treatment also resulted in a substantial decrease in stomatal conductance but had little effect on leaf water potential. A rapid and substantial increase in xylem abscisic acid (ABA) concenation ([ABA]), rather than hulk leaf ABA, was closely related to soil drying and soil compaction. A significant relationship between stomatal conductance (gs) and xylem [ABA] was observed in both species. Artificially feeding ABA solutions to excised leaves of both species showed that the relationship bet ween gs and [ABA] was very similar to that obtained from the whole plant, i.e. the relationship between gs and xylem [ABA]. These results suggest that xylem ABA may act as a stress signal in the control of stomatal conductance.  相似文献   

4.

Background

The study was conducted to evaluate the in vitro thrombolytic activity, and in vivo analgesic, anti-inflammatory and antipyretic potentials of different hydrocarbon soluble extracts of Litsea glutinosa leaves for the first time widely used in the folkloric treatments in Bangladesh. This work aimed to create new insights on the fundamental mechanisms of the plant extracts involved in these activities.

Results

In thrombolytic activity assay, a significant clot disruption was observed at dose of 1 mg/mL for each of the extracts (volume 100 μL) when compared to the standard drug streptokinase. The n-hexane, ethyl acetate, chloroform, and crude methanolic extracts showed 32.23 ± 0.26, 37.67 ± 1.31, 43.13 ± 0.85, and 46.78 ± 0.9% clot lysis, respectively, whereas the positive control streptokinase showed 93.35 ± 0.35% disruption at the dose of 30,000 I.U. In hot plate method, the highest pain inhibitory activity was found at a dose of 500 mg/kg of crude extract (15.54 ± 0.37 sec) which differed significantly (P <0.01 and P <0.001) with that of the standard drug ketorolac (16.38 ± 0.27 sec). In acetic acid induced writhing test, the crude methanolic extract showed significant (P <0.01 and P <0.001) analgesic potential at doses 250 and 500 mg/kg body weight (45.98 and 56.32% inhibition, respectively), where ketorolac showed 64.36% inhibition. In anti-inflammatory activity test, the crude methanolic extract showed significant (P <0.001) potential at doses 250 and 500 mg/kg body weight (1.51 ± 0.04 and 1.47 ± 0.03 mm paw edema, respectively), where ketorolac showed 1.64 ± 0.05 mm edema after 3 h of carrageenan injection. In antipyretic activity assay, the crude extract showed notable reduction in body temperature (32.78 ± 0.46°C) at dose of 500 mg/kg-body weight, when the standard (at dose 150 mg/kg-body weight) exerted 33.32 ± 0.67°C temperature after 3 h of administration.

Conclusions

Our results yield that the crude hydroalcoholic extract has better effects than the other in all trials. In the context, it can be said that the leaves of L. glutinosa possess remarkable pharmacological effects, and justify its traditional use as analgesic, antipyretic, anti-inflammatory, and thrombolytic agent.  相似文献   

5.
Two novel flavonoids with chalcone skeleton, together with seven known flavonoids, were isolated from the stem barks of Litsea rubescens and Litsea pedunculata. The structures of the new compounds were elucidated on the basis of spectral methods including IR, UV, 1D and 2D NMR. The new chalcones were found to contain the rare epoxy or ethylidenedioxy group. This is the first report on the presence of chalcone in the plant genus Litsea. The cytotoxic potential of two new chalcones was evaluated in vitro against three human tumor cell lines. Both new chalcones displayed potent cytotoxic activities against myeloid leukaemia (HL-60) and epidermoid carcinoma (A431) cell lines and more active than cisplatin (DDP). Interestingly, compound 1 exhibited cytotoxic activity against HL-60 with IC50 value 2.1-fold more sensitive to DDP.  相似文献   

6.
Two new butanolides, licunolides A (1) and B (2), were isolated from the roots of Litsea acuminata, together with three known compounds: isolancifolide (3), longifolin (4), and sesquirose furan (5). The structures of compounds 1 and 2 were determined by spectroscopic studies (IR, MS, 1D and 2D NMR) and chemical evidence. This is the first report of 4-hydroxy-5-methylbutanolides with a C10-side chain from a natural source. Longifolin (4) and sesquirose furan (5) showed a significant cytotoxicity against HeLa cell lines in vitro.  相似文献   

7.
中国樟科木姜子属植物纪要   总被引:1,自引:0,他引:1  
描述一新种即沧源木姜子Litsea cangyuanensis J.Li et H.W.Li;一中国新纪录种白叶木姜子L.albescens(Hook.f.)D.G.Long;3个新异名:大叶木姜子L.chunii Cheng var.longipedicellata Yang f.latifolia Yang归并到高山木姜子L.chunii Cheng,狭叶桂北木姜子M.subcoriacea Yang et P.H.Huang val.stenophylla Yang et P.H.Huang归并入桂北木姜子L.subcoriacea Yang et P.H.Huang,狭叶华南木姜子L.greenmaniana Allen val.angustifolia Yang et P.H.Huang归入华南木姜子L.greenmaniana Allen;思茅木姜子L.szemaois(H.Liou)J.Li et H.W.Li作为新等级提升为种;并对秃净木姜子L.kingii Hook.f.与山鸡椒L.cubeba(Lour.)Pers.两者间的差异进行澄清,对台湾产的黄肉树应采用L.hypophaea Hayata和广西产的蜂窝木姜子应采用L.foveola Kosterm.进行了讨论。一个新名称:L.sinoglobosa J.Li et H.W.Li替代同名的L.globosa Yang et P.H.Huang。  相似文献   

8.
Two new flavanocoumarins, 1 and 2 , together with phyllocoumarin ( 3 ) and epiphyllocoumarin ( 4 ), were isolated from the leaves of Litsea coreana Levl. in Anhui Province, China. The structures of 1 – 4 were elucidated by spectroscopic methods. Biological tests revealed that 1 – 4 exhibited moderate anti‐inflammatory activities through inhibition of TNF‐α and IL‐1 production in primary mouse peritoneal macrophages activated with lipopolysaccharides (LPS).  相似文献   

9.
An investigation on the chemical constituents in the root barks of Litsea glutinosa was performed for the first time. Three new lignan glycosides named Litseasins A–C (1–3), together with a known one (4), were obtained. The structures of the new compounds were established through extensive spectroscopic analyses including HR-ESI–MS, NMR, and circluar dichroism (CD). The new compounds were evaluated for their anti-inflammatory activities on lipopolysaccharide (LPS)-induce nitric oxide (NO) production in RAW264.7 murine macrophage cells. However, these compounds showed no inhibition on LPS-induced NO productions.  相似文献   

10.
The isolation and characterisation of nine closely related 3′,4′-disubstituted isoflavones from the aerial parts and roots of Tephrosia maxima  相似文献   

11.
山苍子叶内生真菌的纯化与鉴定   总被引:1,自引:0,他引:1  
本研究选用PDA培养基,通过组织块分离法从山苍子叶中分离得到两株内生真菌。对照真菌鉴定手册,根据菌株和菌丝体形态学特征,并给合ITS区段的碱基序列分析,鉴定两株内生分别属于顶孢霉属和芒果球座菌属。  相似文献   

12.
利用分子蒸馏技术提纯海南山苍子油,用GC对山苍子里面柠檬醛质量分数和收率进行分析,实验表明获得高纯度、高收率柠檬醛的工业条件是:转数395 rpm,加料速度1.5滴/s,冷却水-5℃,一次分馏温度45℃、压力1 mbar;二次分流温度60℃,压力1 mbar,柠檬醛的质量分数为95.68%,产率为86.60%。  相似文献   

13.
A water-soluble arabinoxylan (D-xylose and L-arabinose in the molar ratio 1.0:3.4) was isolated from the mucilaginous bark of Litsea glutinosa (Lauraceae). The results of methylation analysis, partial hydrolysis, and 1H- and 13C-n.m.r. spectroscopy indicated a backbone of (1----4)-linked beta-D-xylopranosyl residues substituted at both positions 2 and 3 with side chains composed of either single or (1----3)-linked arabinofuranosyl residues. Both alpha-L- and beta-L-arabinofuranosyl residues were present. It is possible that side chains composed of two beta-L-arabinofuranosyl residues are attached mainly at O-2 of some xylosyl residues.  相似文献   

14.
The chemical components and antioxidant activity of 16 Rehmannia glutinosa samples were investigated to reveal the high‐quality raw resource for pharmaceutical products. 22 main chemical components were detected with significant content differences (P<0.05). The contents of 14 substances reached the maximum in S1 sample such as catalpol (6.74 mg g?1), rehmaionoside A (1.93 mg g?1) and rehmannioside D (5.13 mg g?1). However, the content distribution of the other eight substances had no obvious change regulation. Three antioxidant evaluation methods commonly showed that S1 sample had strong antioxidant activity with a low IC50 value of 0.022 mg mL?1, a high ABTS value of 524.196 μmol equiv. Trolox g?1, and a high FRAP value of 200.517 μmol equiv. Trolox g?1. Considered the medicinal value, S1 had high quality based on the present phytochemical profiles and antioxidant activity. These results also indicated that the root extracts of R. glutinosa could become useful supplement for pharmaceutical products as new antioxidant agents.  相似文献   

15.
Plants used for traditional medicine contain a wide range of substances that can be used to treat various diseases such as infectious diseases. The present study was designed to evaluate the antileishmanial effects of the essential oil and methanolic extract of Myrtus communis against Leishmania tropica on an in vitro model. Antileishmanial effects of essential oil and methanolic extract of M. communis on promastigote forms and their cytotoxic activities against J774 cells were evaluated using MTT assay for 72 hr. In addition, their leishmanicidal activity against amastigote forms was determined in a macrophage model, for 72 hr. Findings showed that the main components of essential oil were α-pinene (24.7%), 1,8-cineole (19.6%), and linalool (12.6%). Findings demonstrated that M. communis, particularly its essential oil, significantly (P<0.05) inhibited the growth rate of promastigote and amastigote forms of L. tropica based on a dose-dependent response. The IC50 values for essential oil and methanolic extract was 8.4 and 28.9 μg/ml against promastigotes, respectively. These values were 11.6 and 40.8 μg/ml against amastigote forms, respectively. Glucantime as control drug also revealed IC50 values of 88.3 and 44.6 μg/ml for promastigotes and amastigotes of L. tropica, respectively. The in vitro assay demonstrated no significant cytotoxicity in J774 cells. However, essential oil indicated a more cytotoxic effect as compared with the methanolic extract of M. communis. The findings of the present study demonstrated that M. communis might be a natural source for production of a new leishmanicidal agent.  相似文献   

16.
采用HPLc-ELSD法,对6个不同品种(包括野生和栽培)地黄的低聚糖进行含量测定.测定结果表明:不同的地黄品种低聚糖含量差异比较显著;栽培品种‘85 -5’、‘9302’和‘北京1号’低聚糖含量比较接近;野生品种‘BA3’的水苏糖含量普遍较低,而蔗糖含量比较高;‘北京1号’水苏糖含量较高,总低聚糖含量比较均衡,占干重...  相似文献   

17.
山苍子油对小鼠系统性新生隐球菌感染的实验研究   总被引:2,自引:0,他引:2  
目的研究山苍子油治疗小鼠系统性新生隐球菌感染的疗效。方法建立小鼠系统性新生隐球菌感染模型,观察给药后小鼠的中位生存时间,检测小鼠肾脏及肺菌落形成单位计数。结果山苍子油不仅能够显著延长感染小鼠的中位生存时间,提高其生存率,而且可显著增加感染小鼠肾脏及肺菌落清除率。结论山苍子油对系统性新生隐球菌感染小鼠具有治疗作用。  相似文献   

18.
怀地黄ISSR扩增条件优化的研究   总被引:25,自引:2,他引:25  
用CTAB法提取怀地黄嫩叶DNA,进行简单重复间序列标记(ISSR)分析.通过单因子实验分别研究了退火温度、Taq酶单位、Mg2+浓度、dNTP浓度、引物浓度和模板DNA浓度对ISSR-PCR反应的影响,找出各自的合适条件,而且每一个合适条件确定以后都被作为后续研究的一个条件.通过各个因子的组合研究建立了适宜于怀地黄ISSR分析的扩增体系25 μL PCR反应体积,1×Taq DNA酶缓冲液(10 mmol/L Tris-HCl,50 mmol/L KCl,0.1% Trion X-100,pH9.0 ),2.5 mmol/L MgCl2,1.5~1.0 U Taq酶,60 ng模板DNA,0.4 μmmol/L引物,各0.4 mmol/L的dATP、dGTP、dCTP和dTTP.合适的退火温度为53~55℃.为用ISSR技术分析鉴定怀地黄种质资源奠定了良好的基础.  相似文献   

19.
We previously isolated from Nicotiana glutinosa leaves three distinct cDNA clones, NGR1, NGR2, and NGR3, encoding a wound-inducible RNase NW, and putative RNases NGR2 and NGR3, respectively. In this study, we produced RNases NW and NGR3 in Escherichia coli and purified them to homogeneity. RNase NGR3 had non-absolute specificity toward polynucleotides, although RNase NW preferentially cleaved polyinosinic acid (Poly I). Both RNases NW and NGR3 were more active toward diribonucleoside monophosphates ApG, CpU, and GpU. Furthermore, kinetic parameters for RNase NW (K m, 0.778 mM and k cat, 1938 min?1) and RNase NGR3 (K m, 0.548 mM and k cat, 408 min?1) were calculated using GpU as a substrate.  相似文献   

20.
利用平板分离法从怀地黄(Rehmannia glutinosa Libosch)中分离出内生菌共130株,包括67株细菌、50株真菌和13株放线菌。利用大肠杆菌、金黄色葡萄球菌和黑曲霉作为供试菌株,通过对峙试验和平板点接法筛选出8株对3种供试菌株均具有较强拮抗作用的内生菌。经菌种形态观察、生理生化实验以及16S rRNA序列测定,这8株活性内生菌均为假单胞菌属的细菌,并分别与Pseudomonas fluorescens、Pseudomonas thivervalensis、Pseudomonas chlororaphis、Pseudomonas koreensis和一个未定种具有最高相似性。对这8株活性内生菌进行液体发酵、不同有机溶剂抽提和抗菌抗肿瘤研究,结果表明它们的乙醇抽提物和乙酸乙酯抽提物均不同程度地对3种供试菌株和食管癌细胞系Ec9706具有抑制作用。其中2-2号菌株(Pseudomonas chlororaphis)抗菌抗肿瘤作用最强,具有重要的开发价值。  相似文献   

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