Chemotaxonomic significance of volatile compounds in Thymus samius and its related species Thymus atticus and Thymus parnassicus

Thymus samius, a rare species endemic to the island of Samos (East Aegean, Greece), has been considered to be of possible hybrid origin, with Thymus cilicicus, Thymus parnassicus or Thymus zygioides as putative parents. Morphologically it also resembles Thymus atticus. In order to evaluate any possible chemotaxonomic relationships indicated by the qualitative and/or quantitative differentiation of volatile compounds, the essential oils of T. samius, T. parnassicus and T. atticus were analyzed and the oils of T. cilicicus and T. zygioides were used for comparison. T. atticus presents considerable variation in chemical constituents, with all Greek populations being poor in thymol/carvacrol and rich in (E)-nerolidol, germacrene D, (E)-caryophyllene, caryophyllene oxide, 1,8-cineole, α-pinene and camphene, depending on the sample. T. parnassicus shows remarkable qualitative stability in its volatile constituents, and all its populations have a similar profile with (E)-caryophyllene being the most prominent compound. T. samius is characterized by the presence of germacrene D and β-bisabolene, which constitute almost half its oil percentage. This species is also characterized by a low amount of monoterpenes; the latter exist in a considerable percentage in the related species. Our results indicate that T. samius does not show similarity or intermediacy in chemical compounds with any given couple of T. atticus, T. parnassicus, T. cilicicus, or T. zygioides.     

Chemotaxonomic study of the genus Paris based on steroidal saponins

The study of saponins from the genus Paris (Trilliaceae) has led to the isolation of over 70 steroidal saponins. Their distributions in different species are summarised and possible patterns in the modifications of the aglycone moiety, based on a biosynthetic pathway for steroidal saponins, were reviewed in this study. The chemotaxonomic value of these secondary metabolites has been evaluated, and it is suggested that Paris thibetica, Paris vietnamensis, Paris delavayi and Paris pseudothibetica, which contain more active saponins, could be an ideal substitution material for Paris polyphylla Smith var. chinensis, and Paris polyphylla Smith var. yunnanensis. Distribution of the same types of saponins amongst the Trilliaceae suggests a close relationship between the Trillium and Paris.     

壮丽含笑中的倍半萜成分及其化学分类学意义

壮丽含笑 (ＭｉｃｈｅｌｉａｌａｃｅｉＷ Ｗ Ｓｍｉｔｈ)为木兰科含笑属植物 ,常绿乔木 ,分布于我国云南西南部 ,生于海拔 15 0 0ｍ的林中。枝粗壮 ,花梗具佛焰苞状苞片约 5枚 ,心皮狭卵圆形具 3～ 4ｍｍ的花柱等特征 ,形态分类学上认为该种是含笑属中较原始而特殊的种类 (刘玉壶等 ,1996)。通过初步药理筛选实验 ,表明其嫩枝的脂溶性提取物在浓度为 1 5 μｇ/ｍＬ时对两种人肿瘤细胞株ＨＣＴ - 8及ＳＩＨａ的抑制率分别为5 7 0 %及 2 1 3% ,对ＧＬＣ - 82细胞株的抑制率尤其明显 ,为 84 6% ;对ＣｏｎＡ刺激的小鼠脾淋巴细胞增殖反应在浓…     

Volatile Compounds in Thymus sect. Teucrioides (Lamiaceae): Intraspecific and Interspecific Diversity,Chemotaxonomic Significance and Exploitation Potential

Thymus sect. Teucrioides comprises three species, namely, T. hartvigii, T. leucospermus, and T. teucrioides, distributed in Greece and Albania. The volatile constituents of all species of the section were obtained by hydrodistillation and investigated by GC‐FID and GC/MS analyses. Twenty populations were sampled and a total of 103 compounds were identified, representing 98.0–99.9% of the oil compositions. The oils were mainly characterized by high contents of monoterpene hydrocarbons (42.7–92.4%), with the exception of three oils for which oxygenated monoterpenes were the dominating constituents, viz., that of T. hartvigii ssp. macrocalyx, with linalool as main compound (89.2±0.5%), and those of T. hartvigii ssp. hartvigii and of one population of T. teucrioides ssp. candilicus, containing thymol as major component (46.4±3.1 and 38.2±3.9%, resp.). The most common compound in the oils of the 20 populations of the section was p‐cymene. Considerable variation was detected within and among populations, and seven chemotypes were distinguished, i.e., p‐cymene, linalool, p‐cymene/thymol, p‐cymene/γ‐terpinene, p‐cymene/borneol, p‐cymene/γ‐terpinene/borneol, and p‐cymene/linalool chemotypes. Different chemotypes may exist in the same population. Multivariate statistical analyses enabled the segregation of the oils within Thymus sect. Teucrioides into two groups, one consisting of the three subspecies of T. teucrioides and the second comprising the species T. hartvigii and T. leucospermus. A linalool‐rich chemotype, unique within the section, distinguished the oil of T. hartvigii ssp. macrocalyx from all other oils. The high oil content of p‐cymene and the preference for serpentine substrates render T. teucrioides species promising for future exploitation.     

Chemotaxonomic differentiation of coryneform bacteria isolated from biofilters.

Coryneform bacteria that were isolated from biofilters which are used for waste gas treatment of animal-rendering plant emissions were differentiated and partially identified by using chemotaxonomic methods. On the basis of the results of a numerical analysis of whole-cell fatty acid profiles, 79 isolates were divided into two major groups; the members of the first group contained saturated and monounsaturated fatty acids, whereas the members of the second group were characterized by iso- and anteiso-branched fatty acids. Division into subclusters was based mainly on quantitative differences in fatty acid composition and was confirmed by the results obtained for additional chemical markers (e.g., respiratory quinones, mycolic acids, polar lipids, cell wall amino acids, and whole-cell sugar patterns). By combining the results obtained for chemotaxonomic analyses that were performed for strains containing saturated and monounsaturated fatty acids, we were able to identify the genus Corynebacterium (two Corynebacterium species were differentiated on the basis of the occurrence of tuberculostearic acid), the genus Gordona, and the genus Mycobacterium. Among the strains that produced iso-anteiso fatty acid patterns, one subgroup was affiliated with the "nicotianae" group of the genus Arthrobacter; however, some strains contained a new combination of chemical markers. Peptidoglycan type A4 alpha, L-Lys-Gly-L-Glu was combined with menaquinones MK-7 and MK-8, whereas peptidoglycan type A4 alpha, L-Lys-L-Glu occurred together with MK-8 and MK-9. The second subgroup was characterized by a new type B peptidoglycan and MK-11, as well as small amounts of MK-12. Differentiation that was based first on chemotaxonomy and second on physiology gave reliable results. Thus, coryneform strains with new characteristics were isolated from biofilters.     

A chemotaxonomic study of free flavone aglycones from some Iberian Thymus species

Sixteen free flavone aglycones exuded onto the leaf surfaces have been analysed in twenty-three taxa of genus Thymus growing in the Iberian Peninsula. A chemotaxonomic study of these compounds has been carried out. Correlations with morphological classifications and the usefulness of excreted flavonoids as taxonomic markers are discussed.     

Silica-scaled Chrysophytes from Portugal

Phytoplankton samples from lakes, reservoirs and ponds in Central Portugal were obtained and the scale-bearing chrysophytes investigated by electron microscopy. This is the first study on the occurrence and distribution of these organisms in Portugal and in the Iberian Peninsula as a whole. It reports the presence of 23 species of the genera Chrysosphaerella, Paraphysomonas, Spiniferomonas, Mallomonas and Synura . Most of the species found are of worldwide distribution but a few rare organisms were present in some samples. To conclude, the perspectives of future research in Portugal are briefly outlined.     

Chemotaxonomic Studies on Equisetaceous Plants in China

The present paper deals mainly with the chemical contents of the family Equisetaceae in China. The taxonomic value of the flavonol in this family is discussed. The results of chemical investigation show that kaempferol-3,7-diglucoside and kaempferol are the characteristic components of the family; kaempferol-3-diglucoside is characteristic of the genus Hippochaete and quercetin is characteristic of the genus Equisetum. Described in this paper are isolation of 11 compounds and identification of 7 compounds in this experiment, among which kaempferol-3-diglucoside and succinic acid are isolated from Hippochaete hiemale for the first time.     

Chemotaxonomic studies on rhizome extract compositions of twenty Curcuma species from South India

The chemical composition of volatile methanolic rhizome extracts of twenty Curcuma species was studied and the components were identified using gas chromatography–mass spectrometry (GC-MS) method. The major components identified in the majority of the species were beta-caryophyllene epoxide, camphor, retinal and alloaromadendrene oxide. Based on the presence of major chemical components, cluster analysis was performed for all the Curcuma species studied. All the twenty species were grouped based on the presence or absence of a particular compound and a dendrogram was constructed, which grouped the 20 species into eight clusters. By conventional morphological methods, the identification of Curcuma up to species level is difficult; hence the chemical composition of the rhizome methanolic extracts can be used as an important tool for species identification and chemotaxonomic study.     

木通科植物的化学分类

木能科为双子叶植物纲中较原始的一个小科,多为寡种属和单种属,主要分布于东亚地区。我国共有7属29种,其中很多种为传统的药用植物。本文简要综述木通科植物近几十年的化学研究状况,并从化学分类学 的角度探讨木通科属间和与其近缘科之间的系统关系。结果表明齐墩果烷型三匝皂甙作为木通科的特征化不成发在该科的系统分类中具有一定的意义。齐墩果烷型三萜皂甙不仅提示木通科与毛莨科的毛莨亚科的系统联系,而且甙元骨架的氧化水平与科内各属的系统进货也有一定的相关性。     

木通科植物的化学分类

木通科为双子叶植物纲中较原始的一个小科,多为寡种属和单种属,主要分布于东亚地区。我国共有7属29种,其中很多种为传统的药用植物。本文简要综述木通科植物近几十年的化学研究状况,并从化学分类学的角度探讨木通科属间和与其近缘科之间的系统关系。结果表明齐墩果烷型三萜皂甙作为木通科的特征化学成分在该科的系统分类中具有一定的意义。齐墩果烷型三萜皂甙不仅提示木通科与毛茛科的毛茛亚科的系统联系,而且甙元骨架的氧化水平与科内各属的系统进化也有一定的相关性。     

Chemotaxonomic study of the genusTabernaemontana (Apocynaceae) based on their indole alkaloid content

According to their alkaloidal products species of the new genusTabernaemontana can be partly differentiated. This differentiation is in agreement with the old genera classification. From the chemotaxonomic point of view a subdivision of subfam.Plumerioideae of theApocynaceae is proposed.     

Chemotaxonomic identity ofCorynebacterium matruchotii from animal and human dental plaques

Eight strains ofCorynebacterium matruchotii, isolated from the dental plaque of patas monkeys and orangutans as part of a study of the flora of animal plaque, were compared with isolates from human sources. The polypeptide patterns on sodium dodecyl sulfate-polyacrylamide gel electrophoresis were similar, and the animal isolates were not distinguished from human strains by the mean base composition of DNA, the peptidoglycan components, the cell wall carbohydrates, nor the mycolic acids. All strains appear to belong to the same species, which is distinct from other species ofCorynebacterium.     

Chemotaxonomic aspects of some Acacia gum exudates from series Juliflorae*

Data for the chemical composition of the gum exudates from Acacia acradenia, A. aneura, A. acuminata, A. beauverdiana, A. coolgardiensis, A. kempeana, A. microneura, A. resinomarginea, A. stereophylla and A. torulosa are presented. Comparisons with the data reported previously for other species of the series Juliflorae, viz. A. auriculiformis, A. holosericea, A. leptostachya, A. mangium and A. pubifolia confirm that the gums from this series have interesting combinations of chemical properties that are unusual in Acacia. The data do not offer much chemotaxonomic support for the groupings of the Juliflorae suggested by Bentham (1864). On the basis of their gross morphological features, the species under consideration are re-grouped in a way that is also better supported chemically.     

Hepatozoonosis in foxes from Portugal

Hepatozoon, sp. is described for the first time in foxes (Vulpes vulpes silacea) in Portugal. Of 301 foxes examined, 143 (48%) were infected. The gametocyte was the predominant stage of the life cycle and was found in every organ except the bone marrow, where schizonts were the most abundant stage. The morphological similarity of this parasite's gametocytes to Hepatozoon canis is emphasized.     

Chemotaxonomic study of seed glucosinolate composition in Coincya Rouy (Brassicaceae)

A total of 68 populations belonging to the genus Coincya Rouy (Brassicaceae) from the Iberian Peninsula was examined for seed glucosinolate composition. The presence of progoitrin, epiprogoitrin, glucosinalbin and gluconapin was recorded plus a fifth glucosinolate that could not be identified. A geographical clinal variation between progoitrin and epiprogoitrin was observed in the more widespread taxa, C. monensis subsp. orophila (Franco) Aedo, Leadiay & Murioz Garm. and C. moncnsis subsp. cheiranthos var. recurvata (All.) Leadiay. The fewest types of glucosinatc were observed in taxa with morphological characters considered more primitive, viz. subsp. hispida and var. recurvata. On the other hand, more complex and diverse composition was observed in the taxon with more advanced characters, viz. C. rupestris subsp. rupestris Porta & Rigo.