Ribosomal DNA locus evolution in Nemesia: transposition rather than structural rearrangement as the key mechanism?

We investigated chromosome evolution in Nemesia using fluorescent in-situ hybridization (FISH) to identify the locations of 5S and 45S (18–26S) ribosomal genes. Although there was conservation between Nemesia species in chromosome number, size and centromere position, there was large variation in both number and position of ribosomal genes in different Nemesia species (21 different arrangements of 45S and 5S rRNA genes were observed in the 29 Nemesia taxa studied). Nemesia species contained between one and three pairs of 5S arrays and between two and four pairs of 45S arrays. These were either sub-terminally or interstitially located and 45S and 5S arrays were often located on the same chromosome pair. Comparison of the positions of rDNA arrays with meiotic chromosome behaviour in interspecific hybrids of Nemesia suggests that some of the changes in the positions of rDNA have not affected the surrounding chromosome regions, indicating that rDNA has changed position by transposition. Chromosome evolution is frequently thought to occur via structural rearrangements such as inversions and translocations. We suggest that, in Nemesia, transposition of rDNA genes may be equally if not more important in chromosome evolution.     

西藏胡黄连中的环烯醚萜类化学成分

目的：对常用传统中药西藏胡黄连Picrorkiza scrophulariiflora Pennell根茎中环烯醚萜类化学成分进行研究、方法：采用色谱技术进行分离，通过^1H、^13CNMR等坡谱技术确定化合物的结构。结果：分离并鉴定了7个环烯醚萜类化合物，其中3个环戊烷单萜：rehmaglutinA（1）、rehmaglutinD（2）、3＇-methoxyspecionin（3），4个环烯醚萜苷：picrosideⅡ（4）、picrosideⅠ（5）、picrosideⅢ（6）、pikuroside（7）．结论：其中化合物1,2、3和7系首次从该植物中分离得到，3为新的天然产物.     

毛泡桐花中黄酮类成分的分离与结构确定

目的 对泡桐属植物抗菌中草药毛泡桐花Paulownia tomentosa中酚性类活性成分进行分离纯化和结构确定。方法 利用普通硅胶柱色谱和制备薄层色谱等方法进行分离、纯化，并经超导核磁共振(NMR)等现代波谱技术确定其结构。结果 从毛泡桐花的乙醇(95％)室温提取物中获得5个黄酮类的化合物，其结构被确定为：5，4′-二羟基-7，3′-二甲氧基双氢黄酮(I)，5-羟基-7，3′，4′-三甲氧基双氢黄酮(Ⅱ)，diplacone(Ⅲ)，mimulone(Ⅳ)和洋芹素(V)。结论 黄酮类I～V为首次从该属植物中获得，大量黄酮类成分很可能为毛泡桐花的主要活性成分。     

Bioassay-guided isolation of anti-inflammatory, antinociceptive and wound healer glycosides from the flowers of Verbascum mucronatum Lam.

Ethnopharmacological relevance

The leaves, flowers and whole aerial parts of Verbascum L. species have been used to treat respiratory problems, haemorrhoids and other types of inflammatory conditions in traditional Turkish medicine.

Aim of the study

In order to evaluate this traditional information, the anti-inflammatory, antinociceptive and wound healing activities of Verbascum mucronatum Lam. which is used as haemostatic in Turkish folk medicine were investigated.

Materials and methods

In vivo inhibitory effect of the extracts on the carrageenan-induced hind paw edema model in mice was studied for the assessment of anti-inflammatory activity. Moreover, the wound healing potential of the plant were evaluated by using in vivo wound healing experimental models, i.e. incision and excision models on mice and rats, were comparatively assessed with a reference ointment Madecassol^®. Skin samples were also evaluated histopathologically.

Results

The results of these experimental studies exhibited that Verbascum mucronatum displays anti-inflammatory, antinociceptive and wound healing activities. Through bioassay-guided fractionation and isolation procedures four iridoid glucosides, ajugol (1), aucubin (2), lasianthoside I (3), catalpol (4), two saponins, ilwensisaponin A (5) and C (6) and a phenylethanoid glycoside, verbascoside (7) were isolated and their structures were elucidated by spectral techniques. Verbascoside (7) was found to possess significant wound healing activity as well as antinociceptive and anti-inflammatory potentials, per os without inducing any apparent acute toxicity or gastric damage.

Conclusion

The experimental study revealed that Verbascum mucronatum displays remarkable antinociceptive, anti-inflammatory and wound healing activities.     

Bioassay-guided isolation of anti-inflammatory and antinociceptive glycoterpenoids from the flowers of Verbascum lasianthum Boiss. ex Bentham

Infusions of Verbascum lasianthum flowers have been used for hemorrhoids in Turkish folk medicine. In order to evaluate the scientific basis for this practice, in vivo anti-inflammatory and antinociceptive activities of Verbascum lasianthum Boiss. ex Bentham flowers were investigated. A methanolic extract of the flowers was shown to possess significant inhibitory activity in the carrageenan-induced hind paw edema model and in p-benzoquinone-induced writhings in mice. Through bioassay-guided fractionation and isolation procedures eight compounds, 6-O-(4-O-trans-p-coumaroyl)--l-rhamnopyranosylaucubin (1), 6-O-(4-O-trans-p-methoxycinnamoyl)--l-rhamnopyranosylaucubin (2), sinuatol (3), aucubin (4), geniposidic acid (5), catalpol (6), ajugol (7) and ilwensisaponin A (8) were isolated and their structures were elucidated by spectral techniques. An iridoid glucoside, aucubin (4) and a triterpenoid saponin, ilwensisaponin A (8) were found to possess significant antinociceptive and anti-inflammatory activities, per os without inducing any apparent acute toxicity or gastric damage. Results of the present study support the continued and expanded utilization of plants employed in Turkish folk medicine.     

Two new triterpenoids from Picria fel-terrae

Two new triterpenoids, picfeltarraegenin VII (1) and picfeltarraenin X (2), have been isolated from Picria fel-terrae Lour., along with three known ones, picfeltarraegenin VI (3), picfeltarraenins VI (4) and VII (5). Their structures have been elucidated by means of spectroscopic methods.     

A phenylpropanoid glycoside with antioxidant activity from picria tel-ferae

A phytochemical study on Picria tel-ferae resulted in the isolation of a phenylpropanoid glycoside (1), which was reported for the first time from this plant. The structure of compound 1 was identified as 1-O-3,4-(dihydroxyphenyl)- ethyl-beta-D- apiofuranosyl- (1-->4)-alpha-L-rharmnopyranosyl- (1-->3)-4-O-caffeoyl- beta-D-glucopyranoside on the basis of spectroscopic analyses. In addition, it was found that 1 exhibited a remarkable inhibitory effect on lipid peroxidation initiated by either a free radical [AAPH; 2,2'-azobis-(2-amidinopropane)dihydrochloride] or generated hydroxyl radical (Fe2+/ascorbate). These findings, together with those of previous studies, suggest that P. tel-ferae possesses abundant phenylpropanoid glycosides, and the plant might be used beneficially in the treatment of oxidative stress-related human diseases.     

Screening for Cytotoxic and Antimalarial Activities in Desert Plants of the Negev and Bedouin Market Plant Products

Aqueous extracts of 66 desert plants of the Negev and Beer Sheva Bedouin market plant products were tested for antitumor, antimalarial (protozoa) and growth inhibition of wheat-rootlet activities. Pteranthus dichotomus, Gypsophila arabica, Achillea fragrantissima, Urginea maritima, and Solanum elaeagnifolium exhibited strong cytotoxicity (above 97%) against cultured melanoma cell lines. Mesembryanthemum nodiflorum, Gypsophila arabica, Hammada scoparia, Trigonella foenum-graecum and Peganum harmala had more than 80% inhibition both in rootlet and melanoma assays. Hammada scoparia, Pulicaria crispa, Centaurea eryngioides, Echinops polyceras, Ephedra aphylla, Teucrium polium, Phlomis brachyodon, Urginea maritima, Ochradenus baccatus, Verbascum fruiticulosum, Corchorus olitorius, and Peganum harmala demonstrated strong growth inhibition (above 96%) of the malaria parasite Plasmodium falciparum. The plants that were positive for antimelanoma and antimalarial activities have been under further investigation for the isolation and characterization of the anticancer and antimalarial compounds.     

Two new triterpenoids from Picria fel-terrae

Two new triterpenoids, picfeltarraegenin VII (1) and picfeltarraenin X (2), have been isolated from Picria fel-terrae Lour., along with three known ones, picfeltarraegenin VI (3), picfeltarraenins VI (4) and VII (5). Their structures have been elucidated by means of spectroscopic methods.     

The caffeoyl phenylethanoid glycosides from Lindernia ruellioides and their anti-HBV effects

Abstract

Five caffeoyl phenylethanoid glycosides, including two new ones linderruelliosides A (1) and B (2), were isolated from the leaves and stems of Lindernia ruellioides. Their structures were elucidated on the basis of spectroscopic methods, including extensive NMR and MS spectra. In addition, all these compounds were tested for their anti-HBV activity. Compounds 1, 3, and 4 showed anti-HBV activities, with IC₅₀ values of 54.87, 30.74, and 69.02 μM for HBsAg and 26.70, 5.17, and 7.08 μM for HBeAg, respectively.