Two New Bisabolane Sesquiterpenes from Leontopodium longifolium

Two new bisabolane sesquiterpenes were isolated from the roots of Leontoptdium longifolium. Their structures were elucidated as 4α, 5α-diacetoxy-lα-angeloyloxybisabol-2, 9, ll-triene and 4α, 5α-diacetoxy-lα-angeloyloxy-ll-hydroxybisabol-2, 9-diene by spectroscopic methods including the 2D NMR techniques.

In vitro Antioxidant Activity of Leontopodium franchetii Beauv.

[Objectives] To study the in vitro antioxidant activity of L. franchetii Beauv. [Methods] The DPPH and ABTS^+ scavenging rate and reducing power of L. franchetii Beauv. were detected by ultraviolet spectrophotometry. [Results] The 70% ethanol extract of L. franchetii Beauv. had strong antioxidant capacity, and its antioxidant capacity increased with the increase of mass concentration. [Conclusions] The 70% ethanol extract of L. franchetii Beauv. has higher DPPH and ABTS^+ scavenging rate and reducing power.

Identification of Original Plants, Traits, Microstructure and Powder of Leontopodium franchetii Beauv.

[Objectives] This study aimed to provide experimental data for the identification and application of Leontopodium franchetii Beauv. [Methods] The original plants, traits, microstructure and powder of L. franchetii Beauv. were identified. [Results] The identification characteristics of L. franchetii Beauv. in the original plants, traits and microstructure were obvious. [Conclusions] This study can provide reference for the identification of original plants and herbs and the development of quality standards of L. franchetii Beauv. and provide a basis for further research and development.

Determination and Multidimensional Analysis of 22 Kinds of Inorganic Elements in Leontopodium franchetii Beauv. from Different Production Areas

[Objectives]To determine the content of inorganic elements in Leontopodium franchetii Beauv. from different production areas, and provide a reference for quality control, safety assessment, and clinical application of L. franchetii Beauv.. [Methods] The contents of Al, B, Ba, Ca, Cd, Cu, Fe, K, Mn, Mo, Na, Ni, P, Pb, Si, Sn, Sr, Ti, V, Zn, Hg, Cr in the sample of L. franchetii Beauv. were determined by the wet digestion and technique of inductively coupled plasma optical emission spectrometry(ICP-OES), and the principal component analysis was carried out for the determination results. [Results] A total of 20 inorganic elements were detected from the samples of L. franchetii Beauv. from different production areas, among which the contents of Ca, Al, P and Fe were higher. There were significant differences among different elements, and samples of different production areas show similar distribution patterns of main elements. Correlation analysis shows that 17 elements had an extremely significant positive correlation and 19 elements had a significant positive correlation. According to the principal component analysis, B, Ca, K, Mn, Mo, Pb, Sn, Sr, Fe, Ni, Ti, V, Zn, Al, and Cd were characteristic inorganic elements of L. franchetii Beauv. [Conclusions] This method is simple, rapid and accurate, and can be used for the analysis and determination of inorganic elements in L. franchetii Beauv., and provides a theoretical basis for better development and utilization of L. franchetii Beauv.

Quality Evaluation of Leontopodium franchetii Beauv. from Different Localities Based on Moisture,Ash and Extract Contents and Thin-layer Chromatography

[Objectives] The aim was to determine the moisture,ash and extract contents in Leontopodium franchetii Beauv. from different localities. [Methods] The contents of moisture,total ash,acid-insoluble ash and extract in L. franchetii from different localities were determined according to the methods described in Chinese Pharmacopoeia( 2015 Edition). [Results] In the 10 samples,the contents of moisture were all less than or equal to 15. 0%; the contents of total ash were all below 12. 0%; and the contents of acid-insoluble ash were all less than 3. 0%. The contents of water-soluble extract( by cold-soaked extraction method) in the samples were all below 12. 0% except those from Hongyuan Prairie of Sichuan Province and Xinglong Mountain in Lanzhou City,Gansu Province. [Conclusions]The contents of the four indicators measured in this experiment varied by small margins,indicating that the quality was relatively stable. This study provides theoretical data for the revision of the quality standards for L. franchetii.

青藏高原矮火绒草(Leontopodium nanum)叶片性状对海拔高度变化的响应

植物叶片对环境变化十分敏感,能反映植物适应环境所形成的生存策略。为揭示高寒植物叶片性状对海拔高度变化的响应,对位于青藏高原东北部的冷龙岭3400—4200 m之间5个不同海拔高度的矮火绒草(Leontopodium nanum)叶片进行取样,采用常规石蜡制片技术和显微观察方法测定叶片外部形态、表皮气孔特征和解剖结构,探讨其叶片性状随海拔的变化,结果表明:(1)随海拔高度升高,叶面积呈减小的趋势,而比叶重和叶干物质含量增加;(2)叶片下表皮气孔密度随海拔升高呈先增加后下降的趋势,且气孔密度、气孔器面积、长度、宽度和潜在气孔导度指数等气孔特征之间存在显著相关性;(3)叶厚、栅栏组织和海绵组织厚度随海拔升高呈显著增厚的趋势;(4)叶片解剖结构可塑性和相关性分析显示,上、下角质层厚度的可塑性指数最大,而部分解剖结构指标间存在极显著的相关性。研究表明,矮火绒草为适应沿海拔上升温度降低的环境,主要采取叶片变小、变厚的对策,使植物趋于保温、保水和抗机械损伤的方向发展,并将资源最大化地投入到自身生长发育中。

Antagonistic effects of extracts from Artemisia rupetris L. and Leontopodium leontopodioides to CC chemokine receptor 2b(CCR2b)

The present study was designed to establish a suitable assay to explore CCR2 b receptor antagonists from the natural products of Artemisia rupetris and Leontopodium leontopodioides. An aequorin assay was developed as a cell-based assay suitable for 384-well microplate and used for screening CCR2 b receptor antagonists from natural products. Through establishing suitable conditions, the assay was shown to be suitable for screening of CCR2 b receptor antagonists. Seven compounds were identified in preliminary screening. Five of them showed evident dose-response relationship in secondary screening. The structure–activity relationship study suggested that 7-position hydroxyl group of flavonoids was necessary, a polar group should be introduced on the 3-position, and the substituents on 2-position benzene ring of flavonoids have little influence on the potentency of the inhibition activity on CCR2 b receptor. The ortho-position dihydroxyl structure in quinic acid compounds may be important. In conclusion, Compounds HR-1, 5, 7, and AR-20, 35 showed activity as antagonist of CCR2 b receptor, which shed lights on the development of novel drugs as CCR2 b receptor antagonists for preventing inflammation related diseases.

Protective mechanisms of Leontopodium leontopodioides extracts on lipopolysaccharide-induced acute kidney injury via the NF-κB/NLRP3 pathway

Sepsis-induced uncontrolled systemic inflammatory response syndrome(SIRS)is a critical cause of multiple organ failure.Acute kidney injury(AKI)is one of the most serious complications associated with an extremely high mortality rate in SIRS,and it lacked simple,safe,and effective treatment strategies.Leontopodium leontopodioides(Willd.)Beauv(LLB)is commonly used in traditional Chinese medicine for the treatment of acute and chronic nephritis.However,it remains unclear whether lipopolysaccharide(LPS)affects LPS-induced AKI.To identify the molecular mechanisms of LLB in LPS-induced HK-2 cells and mice,LLB was prepared by extraction with 70%methanol,while a lipopolysaccharide(LPS)-induced HK-2 cell model and an AKI model were established in this study.Renal histopathology staining was performed to observe the morphology changes.The cell supernatant and kidney tissues were collected for determining the levels of inflammatory factors and protein expression by ELISA,immunofluorescence,and Western blot.The results indicated that LLB significantly reduced the expression of IL-6 and TNF-αin LPS-induced HK-2 cells,as well as the secretion of IL-6,TNF-α,and IL-1βin the supernatant.The same results were observed in LPS-induced AKI serum.Further studies revealed that LLB remarkably improved oxidative stress and apoptosis based on the content of MDA,SOD,and CAT in serum and TUNEL staining results.Notably,LLB significantly reduced the mortality due to LPS infection.Renal histopathology staining results supported these results.Furthermore,immunofluorescence and Western blot results confirmed that LLB significantly reduced the expression of the protein related to the NF-κB signaling pathway and NLRP3,ASC,and Caspase-1 which were significantly increased through LPS stimulation.These findings clearly demonstrated the potential use of LLB in the treatment of AKI and the crucial role of the NF-κB/NLRP3 pathway in the process through which LLB attenuates AKI induced by LPS.

火绒草属植物化学成分及药理作用研究进展

火绒草属植物为高原药用植物,在民间广为使用.火绒草属植物主要有黄酮类、苯丙素类、甾体类、酚酸类及萜类等活性成分,具有保护肝肾、治疗糖尿病、抑菌、抗炎、抗氧化等多种药理活性.通过查阅火绒草属植物研究的相关文献,从化学成分、药理活性及临床应用等方面进行全面综述,以期为该类药用植物的进一步研究提供文献资料.

火绒草属药学研究新进展

在广泛文献检索基础上,对火绒草属的种属、成分、药理、临床应用进行了概述,为深入开发利用提供参考依据。

响应面法优化火绒草中总黄酮与总酚酸的提取工艺研究

为探究野生火绒草(Leontopodium leontopodioides(Wild.)Beauv)总黄酮与总酚酸最佳提取工艺及抗氧化活性,本试验采用快速溶剂萃取法探索萃取温度、循环次数、加热时间及萃取压力对火绒草总黄酮、总酚酸提取含量的影响,通过单因素试验和响应面设计法确定了活性物质的最佳提取工艺。结果表明:当使用70%乙醇提取火绒草中总黄酮时最佳提取工艺为:萃取温度93℃,循环次数3次,加热时间20 min,萃取压力102 bar,提取含量为(45.45±0.36)mg·g^(-1);总酚酸最佳提取工艺为:萃取温度90℃,循环次数3次,加热时间19 min,萃取压力97 bar,提取含量为(23.52±0.34)mg·g^(-1)。火绒草总黄酮提取液对DPPH自由基和ABTS自由基的IC_(50)为0.012 mg·mL^(-1)和0.356 mg·mL^(-1),具有一定的还原力。本研究可为火绒草活性物质的提取工艺及加工利用提供可靠的理论依据和详实的科学参考。

火绒草属植物的化学成分和药理活性研究进展

对国内外有关火绒草属药用植物的研究进展进行了综述 ,涉及到该属植物的资源分布、化学成分、药理活性和临床作用 。

火绒草提取物抗氧化活性的研究

测定火绒草水提物和醇提物中多酚及总黄酮含量,证实水提物和醇提物中含有以黄酮类为主要成分的多酚类物质。通过测定火绒草提取物的总还原力,超氧阴离子自由基(O2.)、羟自由基(.OH)清除能力、脂质过氧化抑制作用、清除亚硝酸盐自由基和亚硝胺阻断率,表明火绒草水提物和醇提物具有较强的还原性和清除.OH和O2.的活性,且醇提物的作用比水提物更有效;对脂质过氧化的抑制率达到60%以上。火绒草提取物具有较强的清除亚硝酸钠和阻断亚硝胺合成的能力,水提物对亚硝酸盐最大清除率为77.7%,醇提物对亚硝胺合成的阻断率98.0%。

不同海拔火绒草光合特性的研究

对生长于青藏高原东北部3个不同海拔地区2300、2700和3800m的火绒草叶片的光合特性进行了比较研究.结果发现,随着海拔的升高,叶绿素含量有降低的趋势,而叶绿素a/b比值及类胡萝卜素相对含量呈上升趋势.与海拔2300m处的相比,生长于海拔3800m处的火绒草的净光合速率、表观量子效率和光补偿点较低,但光饱和点较高.研究表明,火绒草在光合特性上的变化是对逆境的一种适应,是青藏高原特殊生态条件长期胁迫的结果.

乌鲁木齐河源区不同海拔的火绒草叶片结构特征的比较研究

采用PEG和Epon 812二次包埋方法,利用光学显微镜和扫描电子显微镜对乌鲁木齐河源区海拔4000m、3400m、2500m三种不同高度的火绒草(Leontopodiumleontopodiodes(Willd.)Beauv.)叶片剖面及表面结构进行了观察.结果表明:火绒草叶片既具有中生植物又兼有旱生和湿生植物的部分结构特征;其叶片厚度、表皮细胞外壁角质层表面、外角质层蜡质分泌物的有无、表皮细胞形状、气孔器分布特征、保卫细胞极区"T"型角质加厚程度、气孔开口(长/宽)、气孔密度、维管束形态、CTR值、叶肉细胞叶绿体含量等性状特征,在不同海拔的火绒草间呈现出明显差异;而表皮的气孔水平位置类型、毛状附属器等性状则差异较小.数值分析火绒草叶结构各类性状以及不同性状状态的组合,显示出个体形态的多样性及其对高山环境和海拔高度的适宜性特征.

青藏高原火绒草斑块群落空间格局分析

以青藏高原两种生境(阴坡和阶地)和4个斑块大小等级水平(等级1:0.2—0.6m2,G1;等级2:0.6—2 m2,G2;等级3:2—3.6 m2,G3和等级4:3.6—8.6 m2,G4)的火绒草(Leontopodium nanum)群落为对象,利用幂乘方法则,分析了其种群和群落空间异质性和群落物种多样性特征,明晰了优势种、亚优势种、伴生种和偶见种对其植被分布格局的影响。结果表明:各火绒草斑块的群落空间分布格局均呈集群分布,植物种的随机出现频率和实际出现频率的方差对数值与其幂乘方法吻合性较高(R2﹥0.8),幂乘方法能对火绒草斑块植被空间分布格局进行客观分析。优势种火绒草和线叶嵩草(Kobresia capillifolia),亚优势种球花蒿(Artemisia smithii)和珠芽蓼(Polygonum viviparum)等的相对空间异质性(ε)高于群落的空间异质性(δC),位于直线y=0上方,使群落趋于集群分布;伴生种西北针茅(Stipa krylovii)、瑞香狼毒(Stellera chamaejasme)和苔草(Carex sp)等的ε与群落的δC类似,位于直线y=0附近,它们维持群落自身空间分布状态;偶见种的ε低于群落的δC,位于直线y=0下方,降低群落的集群分布。随火绒草斑块等级水平的增加,群落物种数呈增加,丰富度指数DGI呈降低变化。一般火绒草斑块的δc和βw为阶地﹥阴坡,DGI为阶地﹤阴坡;两种生境下,植物种组成的相似性G1斑块较低,G2—G4斑块较高。火绒草斑块的群落分布格局主要由优势种和亚优势种及偶见种的ε决定。

火绒草正丁醇层化学成分的分离与鉴定

目的研究中药火绒草正丁醇层的化学成分。方法采用反复硅胶柱色谱法、Sephadex LH-20柱色谱法和反复重结晶等进行分离纯化,并通过波谱分析技术鉴定其化学结构。结果从火绒草中分离得到5个化合物,分别鉴定为：木犀草素-3′-O-β-D-葡萄糖苷（luteolin-3′-O-β-D-glucoside,1）、山奈酚-3-O-β-D-葡萄糖苷（kaempferol-3-O-β-D-glucoside,2）、金圣草素-4′-O-β-D-葡萄糖苷（chrysoeri-ol-4′-O-β-D-glucoside,3）、甘草苷（liquiritin,4）、腺苷（adenosine,5）。结论化合物2-5为首次从火绒草属植物中分离得到,化合物1为首次从火绒草中分离得到。

火绒草黄酮类成分的分离与结构鉴定

目的对火绒草的化学成分进行研究,为进一步开发利用该植物资源提供依据。方法采用反复正相硅胶、反相ODS、Sephadex LH-20等柱色谱以及高效液相色谱法等手段进行分离纯化,并通过理化性质与光谱分析鉴定化合物的结构。结果从火绒草体积分数为70%的乙醇溶液提取物中分离鉴定了9个黄酮类化合物,分别为槲皮素-3-O-β-D-吡喃葡萄糖苷(quercetin-3'-O-β-D-gluco-pyranoside,1)、槲皮素-3'-O-β-D-葡萄糖苷(quercetin-3'-O-β-D-glucopyranoside,2)、5,7,3',4'-tetra-hydroxy-3-methoxyflavone(3)、5,7,3',4'-tetrahydroxy-3-methoxyflavonol-3'-O-β-D-glucopyranoside(4)、山柰酚(kaempferol5,)、山柰酚-3-O-β-D-吡喃葡萄糖苷(kaempferol-3-O-β-D-glucopyranoside6,)、3-甲基-山柰酚(3-methyl-kaempferol,7)、3-甲醚-山柰黄素-7-O-β-D-吡喃葡萄糖苷(3-methylether-kaempferol-7-O-β-D-glucoside,8)、木犀草素-3'-O-β-D-葡萄糖苷(luteolin-3'-O-β-D-glucoside9,)。结论化合物2-57、8、为首次从火绒草属植物中分离得到。

火绒草中的黄酮苷类成分

目的研究火绒草[Leontopodium leontopodioides(Wild.)Beauv.]中黄酮苷类化学成分。方法采用反复硅胶柱色谱法、Sephadex LH-20柱色谱法、ODS柱色谱法和反复重结晶等方法进行分离纯化,并通过理化常数测定和波谱分析鉴定了其化学结构。结果从体积分数为60%的火绒草乙醇溶液提取物中分离得到5个化合物,并鉴定其结构为:芹菜素-7-O-β-D-吡喃葡萄糖苷(apigenin-7-O-β-D-glu-copyranoside1)、木犀草素-4′-O-β-D-吡喃葡萄糖苷(luteolin-4′-O-β-D-glucopyranoside2)、6-羟基-木犀草素-7-O-β-D-吡喃葡萄糖苷(6-hydroxyluteolin-7-O-β-D-glucopyranoside3)、6-羟基-芹菜素-7-O-β-D-吡喃葡萄糖苷(6-hydroxyapigenin-7-O-β-D-glucopyranoside4)、槲皮素-3-O-β-D-吡喃葡萄糖苷(quercetin-3-O-β-D-glucopyranoside5)。结论化合物4,5为首次从火绒草属植物中分离得到,化合物2,3为首次从本植物火绒草中分离得到。

火绒草中酚类成分的分离与鉴定

目的对火绒草的化学成分进行分离与鉴定。方法应用硅胶柱色谱、葡聚糖凝胶柱色谱和高效液相制备色谱分离纯化,根据理化性质和波谱数据确定化合物的结构。结果从火绒草中分离得到10个化合物,分别鉴定为咖啡酸乙酯(ethyl caffeate,1)、芹菜素(apigenin,2)、对羟基苯甲酸(P-hydroxybenzoic acid,3)、原儿茶醛(protocatechuic aldehyde,4)、原儿茶酸(protocatechuic acid,5)、咖啡酸(caffeic acid,化合物6)、槲皮素(quercetin,7)、木犀草素(luteolin,8)、对羟基桂皮酸(p-hydroxy cinnamic acid,9)、阿魏酸(ferulic acid,10)。结论化合物1-3、8首次从火绒草中分离得到,化合物1-3为首次从火绒草属植物中分离得到。