紫锥菊多倍体诱导与鉴定

本实验以紫锥菊愈伤组织上刚分化出的不定芽为材料,用不同浓度秋水仙素溶液对其进行诱导,确定最佳处理浓度和处理时间,并对诱导的多倍体与二倍体进行形态、显微、染色体及过氧化氢酶(CAT)活性的比较鉴定.结果表明:0.025%秋水仙素浓度处理24h的诱导效果最好,诱导率达42.85%;多倍体植株叶片肥厚、根粗壮,气孔面积极显著地大于二倍体植株,染色体数从24～28条不等,CAT平均酶活性是二倍体的2.1倍.     

紫锥菊的生药学研究

采用来源鉴定、性状鉴定、显微及理化鉴定的方法研究紫锥菊的生药学内容,为制定药材质量标准、研究、开发和利用紫锥菊的药用资源提供了理论依据。     

无机盐和蔗糖浓度对白色紫锥菊不定根生长及次生代谢产物积累影响

利用组织培养技术结合高效液相色谱法,考察了液体悬浮培养中无机盐和蔗糖浓度对白色紫锥菊不定根生长以及紫锥菊苷、菊苣酸、氯原酸和酚类化合物积累的影响.结果表明:白色紫锥菊不定根在高或低浓度无机盐和蔗糖培养基中的生长及次生代谢产物含量均较低,不定根生长最适培养基为0.75 MS +5％蔗糖,培养30 d后不定根中紫锥菊苷含量为7.40 mg/g DW,菊苣酸为3.96 mg/g DW,氯原酸含量达3.79 mg/g DW,总酚含量达25.62 mg/g DW.本研究为进一步大规模培养富含紫锥菊苷、菊苣酸的白色紫锥菊不定根奠定了理论和实践基础.     

紫锥菊属三种植物的抗氧化性能研究

采用分光光度法和电子顺磁共振法对紫花松果菊、狭叶松果菊、白花松果菊乙醇提取物的抗氧化性能进行了分析研究。结果表明,狭叶松果菊、白花松果菊、紫花松果菊提取物对羟自由基的清除率分别是76.4%、68.1%、61.5%,对超氧阴离子自由基的清除率分别是80.6%、85.7%、74.2%,对香烟烟气自由基的平均清除率分别是31.8%、19.4%、25.1%。     

紫锥菊愈伤组织诱导及生物活性成分分析

以紫锥菊(Echinacea purpurea)无菌苗为材料,研究了不同激素配比条件下不同外值体愈伤组织的诱导及所诱导的愈伤组织中的主要成分多糖和总酚,并应用高效液相色谱法对根愈伤组织提取物与紫锥菊根提取物中的酚酸类物质进行了比较分析.结果表明,紫锥菊不同部位愈伤组织诱导的最适宜激素配比不同,其中根愈伤组织诱导的最佳激素配比为0.5 mg/L 2,4-D 0.5 mg/L 6-BA.叶、茎、根诱导愈伤组织的多糖含量分别为10.15、11.84、14.49 mg/g干重;总酚含量分别为52.16、28.144、7.99 mg/g干重.根愈伤组织总酚和多糖含量均较高,其提取物的酚酸类物质的高效液相色谱与紫锥菊根提取物图谱主峰一致,且生长速度快、质地疏松,是细胞培养获取紫锥菊主要生物活性成分的适宜材料.     

大孔吸附树脂对紫锥菊提取物中菊苣酸分离纯化的研究

采用大孔吸附树脂分离纯化紫锥菊提取物中免疫活性成分菊苣酸,7％(v／v)的甲醇-水溶液洗脱,HPLC法对产品中菊苣酸含量进行检测分析。该法能把紫锥菊提取物中菊苣酸含量(4％)提高9倍左右,回收率达到95％以上,且操作简单,可用于菊苣酸的分离纯化。     

紫锥菊挥发性成分分析研究

采用气-质(GC-MS)联用技术结合顶空固相微萃取(HS-SPME)与传统共水蒸馏法,对紫锥菊植物干花与干根中挥发性成分进行分析方法研究。GC-MS(配N ist2005标准质谱库)从传统方法提取的紫锥菊干根挥发油中分离分析出188个峰,初步鉴定出68种化合物,从聚二甲基硅氧烷(PDMS 7,100μm)及聚丙烯酸酯(PA 85μm)三种固相微萃取涂层吸附的紫锥菊干花挥发性成分中分别分离分析出27、118、105个峰,各自鉴定出1、22、23种化合物。对不同处理方法及紫锥菊植物不同部位所得数据进行了相识性与差异性的比较,所建分析方法及所得结果为了解紫锥菊植物体挥发性有效成分提供了参考。     

天麻成分对羟基苯甲醛抗血小板聚集作用及急性毒性研究

为探讨天麻成分对羟基苯甲醛的抗血小板聚集作用,本实验以二磷酸腺苷(ADP)、花生四烯酸(AA)、血小板活化因子(PAF)为诱导剂,探讨了对羟基苯甲醛的体外抗血小板聚集活性;采用ADP静脉注射致小鼠肺栓塞方法以及下腔静脉结扎致大鼠静脉血栓方法,考察了对羟基苯甲醛的体内抗血小板聚集活性;并对经口给药的对羟基苯甲醛的急性毒性进行了检测。结果表明,天麻成分对羟基苯甲醛对ADP诱导的家兔体外血小板聚集有明显的对抗作用,其半数抑制率(50%inhibitory concentration,IC50)为2mmol/L,对PAF诱导的家兔体外血小板聚集无明显影响;天麻成分对羟基苯甲醛能明显降低小鼠肺栓塞死亡率,并显著对抗大鼠下腔静脉血栓的形成。说明天麻成分对羟基苯甲醛在体外、体内均具有显著的抗血小板聚集活性。急性毒性研究结果表明天麻成分对羟基苯甲醛经口给药的小鼠半数致死量(lethal dose 50,LD50)为1.23 g/kg。     

紫锥菊多糖抑制致病性大肠埃希菌细胞黏附的试验研究

目的研究紫锥菊多糖能否影响致病性大肠埃希菌对细胞的黏附。方法使用PK-15细胞进行黏附试验及黏附抑制试验。结果发现紫锥菊多糖浓度为1.6 mg/ml时,对细菌黏附细胞的抑制作用最好,黏附率由50个细菌/细胞降低到6.8个细菌/细胞。结论紫锥菊多糖对致病性大肠埃希菌的细胞黏附具有抑制作用,提示该多糖具有调节肠道微生态的潜在应用价值。     

紫锥菊单咖啡酰酒石酸和菊苣酸提取工艺优化

采用正交试验设计,选取乙醇体积浓度百分比、提取温度、提取时间、抗氧化剂用量等因素,优化紫锥菊Echinacea purpurea单咖啡酰酒石酸和菊苣酸的加热回流提取工艺,并考察加入抗氧化剂对提取效果的影响。结果表明,优化的提取条件是以25%乙醇,在80 ℃回流提取90 min。抗氧化剂用量对提取效果影响不显著。优化后的加热回流提取条件对紫锥菊单咖啡酰酒石酸和菊苣酸的提取均适用,提取中无需加入抗氧化剂。     

Effects of phenytoin and Echinacea purpurea extract on proliferation and apoptosis of mouse embryonic palatal mesenchymal cells

Cleft palate is one of the most common birth defects. Several environment factors are involved in the disorder, such as smoking, vitamin deficiency and teratogens. We investigated the teratogenic agent phenytoin and extract of the immunostimulant Echinacea purpurea in the etiology of cleft palate associated with the proliferation and apoptosis of mouse embryonic palatal mesenchymal (MEPM) cells. We measured the effects of phenytoin, E. purpurea extract, and the mixture of phenytoin and E. purpurea extract on the cell viability of MEPM cells by CCK‐8 assay and on the proliferation and apoptosis of MEPM cells by BrdU labeling assay, flow cytometry, and TUNEL assay. Exposure to phenytoin for 24 h inhibited cell proliferation and increased cell apoptosis of MEPM cells, and E. purpurea extract had the reverse effect. Importantly, treatment with the mixture of phenytoin and E. purpurea extract increased the proliferation and decreased the apoptosis of MEPM cells as compared with treatment with phenytoin alone. The teratogenic effect of phenytoin on cleft palate is associated with the proliferation and apoptosis of MEPM cells, and E. purpurea extract may have a protective effect. J. Cell. Biochem. 112: 1311–1317, 2011. © 2011 Wiley‐Liss, Inc.     

Elicitation of secondary metabolism in Echinacea purpurea L. by gibberellic acid and triazoles

In vitro bioreactor production of Echinacea purpurea L. was used to facilitate the screening of compounds capable of eliciting increased secondary metabolite production. Based on previous experience with various bioreactors, the Southern Sun Liquid Lab Rocker was selected for this study as it produces healthy, vigorous, whole plants. The focus of the present study was to quantify the concentration of the medicinally important secondary metabolites caftaric acid and cichoric acid and to study the effect of growth regulators on the production of these compounds in this system. Both marker compounds were produced at levels that compared favorably to field grown plants. Application of gibberellic acid (GA₃), paclobutrazol, uniconazole and a combined treatment of GA₃ with paclobutrazol to the in vitro plants generally increased the concentration of caftaric acid in the roots with little effect on the concentration in the shoots. The concentration of cichoric acid was higher in the roots of treated plants than in the roots of control plants, but lower in corresponding shoots. The present study highlights the use of in vitro production of whole plants as a model system for studying the regulation of plant secondary metabolism in a controlled environment.     

Insulin-like 3 expression and fibrosis induction after intra-testicular injection of magnetic nanoparticles in rat testis and the ameliorative role of Echinacea purpurea extract

The World Health Organization has approved magnetic nanoparticles (MNP) for use as a contrast agent for magnetic resonance imaging or tumor hyperthermia treatment. MNP are toxic over time after intra-testicular injection. A clear strategy to ameliorate the toxic side effects of MNP in normal tissues after medical application has not yet been developed. We used an extract of Echinacea purpurea (EP) as a natural source of antioxidant and free radical scavenging product for detoxification of MNP in testicular tissues. MNP localization in the interstitial area of testicular tissue reduced the expression of insulin-like factor 3 (INSL3) proteins as well as serum testosterone levels. Further, MNP caused accumulation of both collagen and elastin in the interstitial area and increased the thickness of the tunica albuginea. Injection of MNP during administration of EP extract for short periods slightly reduced the toxic side effects of MNP. After extended exposure to EP extract, INSL3 expression and testosterone returned to near control levels. Also, collagen and elastin accumulation caused by MNP was reduced after extended exposure to EP extract. We believe that the ameliorative effect of EP extract is due to its antioxidant properties.     

Floral nectar production and nectary anatomy and ultrastructure of Echinacea purpurea (Asteraceae)

BACKGROUND AND AIMS: In spite of the impressive species diversity in the Asteraceae and their widespread appeal to many generalist pollinators, floral-nectary ultrastructure in the family has rarely been investigated. To redress this, a study using Echinacea purpurea, a plant of horticultural and nutraceutical value, was undertaken. Nectar secretion of disc florets was compared with floral nectary ultrastructure taking into account nectar's potential impact upon the reproductive success of this outcrossing species. METHODS: Micropipette collections of nectar in conjunction with refractometry were used to determine the volume and nectar-sugar quantities of disc florets throughout their phenology, from commencement of its production to cessation of secretion. Light, scanning-electron and transmission-electron microscopy were utilized to examine morphology, anatomy and ultrastructure of nectaries of the disc florets. KEY RESULTS: Florets were protandrous with nectar being secreted from anthesis until the third day of the pistillate phase. Nectar production per floret peaked on the first day of stigma receptivity, making the two innermost whorls of open florets most attractive to foraging visitors. Modified stomata were situated along the apical rim of the collar-like nectary, which surrounds the style base and sits on top of the inferior ovary. The floral nectary was supplied by phloem only, and both sieve elements and companion cells were found adjacent to the epidermis; the latter participated in the origin of some of the precursor cells that yielded these specialized cells of phloem. Companion cells possessed wall ingrowths (transfer cells). Lobed nuclei were a key feature of secretory parenchyma cells. CONCLUSIONS: The abundance of mitochondria suggests an eccrine mechanism of secretion, although dictyosomal vesicles may contribute to a granulocrine process. Phloem sap evidently is the main contributor of nectar carbohydrates. From the sieve elements and companion cells, an apoplastic route via intercellular spaces and cell walls, leading to the pores of modified stomata, is available. A symplastic pathway, via plasmodesmata connecting sieve elements to companion, parenchyma and epidermal cells, is also feasible. Uncollected nectar was reabsorbed, and the direct innervation of the nectary by sieve tubes potentially serves a second important route for nectar-sugar reclamation. Microchannels in the outer cuticle may facilitate both secretion and reabsorption.     

Echinacea purpurea microbiota: bacterial–fungal interactions and the interplay with host and non-host plant species in vitro dual culture

• Important evidence is reported on the antimicrobial and antagonistic properties of bacterial endophytes in Echinacea purpurea and their role in the modulation of plant synthesis of bioactive compounds. Here, endophytic fungi were isolated from E. purpurea, and the dual culture approach was applied to deepen insights into the complex plant–microbiome interaction network.
• In vitro experiments were carried out to evaluate the species specificity of the interaction between host (E. purpurea) and non-host (E. angustifolia and Nicotiana tabacum) plant tissues and bacterial or fungal endophytes isolated from living E. purpurea plants to test interactions between fungal and bacterial endophytes.
• A higher tropism towards plant tissue and growth was observed for both fungal and bacterial isolates compared to controls without plant tissue. The growth of all fungi was significantly inhibited by several bacterial strains that, in turn, were scarcely affected by the presence of fungi. Finally, E. purpurea endophytic bacteria were able to inhibit mycelial growth of the phytopathogen Botrytis cinerea.
• Bacteria and fungi living in symbiosis with wild Echinacea plants interact with each other and could represent a potential source of bioactive compounds and a biocontrol tool.

     

植物中异戊烯基取代的酚类化合物及其分布

异戊烯基取代的酚类化合物由UbiA家族的异戊烯基转移酶(prenyltransferase)催化异戊烯基转移到芳香族化合物母核上,其亲脂性较无异戊烯基取代的化合物明显增强,并提高了与生物膜的亲和力,从而形成了各种具有重要生物学功能的活性分子,在植物防御和人体健康方面具有重要作用。本综述总结了538种异戊烯基酚类化合物的取代基类别和取代位点等,为发掘植物中新型异戊烯基转移酶,以及受体和供体的选择提供参考,以期有更多异戊烯基转移酶可应用于合成生物学来生产具有重要活性的异戊烯基酚类化合物。该文对国内外报道的378种类黄酮,80种香豆素类,27种醌类,32种二苯乙烯类,16种对羟基苯甲酸类,5种苯丙酸类共计538种异戊烯基取代的酚类化合物的取代基类别、取代位置以及在植物中的分布进行总结,发现异戊烯基酚类化合物主要分布在28个科中,且以C5和C10取代基为主。该文还综述了已鉴定功能的30余种植物芳香族异戊烯基转移酶。     

不同成熟度老鹰茶中酚类化合物含量及抗氧化活性研究

为了探究两种不同成熟度老鹰茶中酚类化合物含量及抗氧化活性的差异,以对其进行辨识及质量评价,该研究利用液相色谱-串联质谱(LC-MS/MS)法测定老鹰茶中15种酚类化合物,采用DPPH自由基清除率、ABTS⁺自由基清除率、Fe³⁺还原能力评价两种茶叶抗氧化能力,再通过数据统计分析探讨两种老鹰茶酚类化合物含量及抗氧化活性的差异,并进一步探索老鹰茶中不同酚类化合物对于抗氧化的贡献。结果表明:(1)嫩叶茶中儿茶素、对香豆酸、异槲皮苷、金丝桃苷、烟花苷、紫云英苷、山奈酚、槲皮素、阿福豆苷含量显著高于老叶茶,其中儿茶素、异槲皮苷、紫云英苷平均含量比老叶茶分别高1 039.43、169.12、257.35 mg·100 g^-1。聚类分析(HCA)、主成分分析(PCA)、正交偏最小二乘判别分析(OPLS-DA)均可将二者区分。(2)方差分析(ANOVA)结果显示在抗氧化能力上,二者在DPPH自由基清除率、ABTS⁺自由基清除率、Fe³⁺还原能力之间具有显著性差异,嫩叶茶优于老叶茶。(3)偏最小二乘回归分析(PLSR)法提示老鹰茶中的异槲皮苷、儿茶素、紫云英苷、绿原酸、金丝桃苷、对香豆酸、山奈酚是其发挥抗氧化效能的主要酚类化合物。该研究结果可为老鹰茶的质量控制及应用推广提供一定的参考。     

The role of phenolic compounds in disease resistance in geranium

The present study was conducted in the hill station of G B Pant University of Agriculture and Technology, Ranichauri, Uttarakhand, which is known for its diversity in medicinal and aromatic plants. The plant geranium, also known as rose or lemon geranium is highly valued for its essential oil which is used in the cosmetic and preferring industries. The plant suffers due to stem and root rot both during summer and winter seasons. In the present study, geranium plants showed maximum stem rot incidence (60.55%) and plant mortality (17.20%) during the winter season, whereas in summer the crops showed maximum root rot and wilt complex incidence (38.33%) with plant mortality up to (12.22%). The average stem rot mortality was comparatively low (16–20%) in summer but increased to 18–26% in winter crop. Several phenolic acids such as as tannic, gallic, caffeic, ferulic and benzoic were detected by using high performance liquid chromatography (HPLC) in variable amounts in these plants. The disease intensity varied from 97.77 to 92.46% from season to season. The significance of the phenolic compounds is discussed in relation to disease prevalence.