| Sesquiterpenoid is a kind of natural compounds which is most rich in plants. As is known to all, Sesquiteipenoids are always active and have become important feedstocks used in pharmaceutical industries, food and cosmetics. These compounds are abundant in the three genus of Asteraceae. Senecio, Ligularia and Farfugium and even have been regarded as the characteristic compounds in modern Trib. Senecioneae plants.Finding and extracting sesquiteipenoids from Senccio has always been a hotspot in pharmacochemistry and related functional food research. At present, more than600sesquiteipenoids have been found and extracted from about150plants of this genus. As new types of sesquiteipenoids are increasingly discovered from the species of Senecio, the study of distribution and evolution pattern of these compounds in those plants is also becoming a focus issue. However, only a few kinds of sesquiterpenoid compounds have been studied in a small number species of Senecio so far. and thus lead to the limited conclusions. Therefore, a comprehensive study of classification and distribution of sesquiteipenoids in Senecio is essential to the sesquiterpenoid study. There are more than1200species of Senecio in the world. The widely distribution, the diversification of habitats and the variation of morphology of this genus make it extremely difficult for species identification and interspecific relationship inference. These problems become a bottleneck for the study of sesquiterpenoids distribution in Senecio. Hence the multidisciplinary analyses are urgently needed to study the types of sesquiterpenoid compounds in Senecio, that is clearing classification and relationship of Senecio using phylogenetic approach and furthermore summarizing the new types of sesquiterpenoids using taxonomical method. These comprehensive sampling along with the multidisciplinary analyses can provide a more objective study. Consequently, these results would provide new insight in finding new compounds through plant genetic relationship. Additionally, it also has a great practical value in the development and utilization of medicine and food resources. In the meantime, this kind of research is significant to the protection of sesquiterpenoids resources of Senecio.ly,quenal nomen nudum species;lationship s with a world wide Materials of Senecio and Ligularia were collected respectively from the Kunyu Mountains, Shandong province and Changbai mountains, Jilin Province. Materials of Farfugium were collected from suburb of Zhoushan city. Zhejiang Province. The sesquiterpenoids were extracted and purified using column chromatography, thin layer chromatography, and recrystallization techniques. The compound structures were identified using modern spectral analysis. As a result, we got35sesquiterpenoids including the26known kinds, seven new kinds and one novel firstly extracted from natural resources. The seven new sesquiterpenoids were:(1)6β-angeloyloxy-eremophila-1(10),7(11)-diene-12,8β-lactone(2)5α-Hydroxy-4(15)-eudesmene-1-one(3)7R*,10S*-epoxy-3E,5E-farnesadien-1,2,11-triol(4) Fischelactone(5) Fischelactone B(6)Eremophila-1(10),7(11),8-trien-12,8-lactam(7)3β-angeloyloxy-6β,8β-dihydroxy-9β-Senecioyloxyeremophil-7(11)-en-12,8α-lactoneWe comprehensively collected information of Senecio L. species reported with sesquiterpenoids. Up to now it is also one of the most comprehensive studies of sesquiterpenoids types with the largest species number in Senecio. As a result, we obtained a total of622sesquiterpenoids from149species of Senecio in the world. The structures and types of the compounds were discussed, and their possible biosynthesis methods were investigated, too.TThis research firstly applied quantitative taxonomy method into study of sesquiterpenoid type in Senecio. At first, textual researches of scientific names were conducted and characters of geographical distributions of these species were analyzed. A series of new taxonomic informations were confirmed and accepted in this paper including26genus-transferred species.27synonym species.10unresolved name species.13nomen nudum species. The geographical distribution investigation showed that the geographical distributions of Senecio exhibited both worldwide extension and region limitation features which existed mostly in torrid and subtropical zones. Moreover, structures of622sesquiterpenoids were classified and digitized. Sesquiterpenoids type tree was built through UPGMA method. The results showed that these compounds could be divided into7groups:1. Bisabolane;2. Cacalol:3. Eremophilane;4. Furanoeremophilane;5. Eremophilenolide;6. Eudesmane;7. Germacrane. We found that55of the149species of Senecio (37%) were furanoeremophilanes. which was the most common type of sesquiterpenoid shared by the largest number of studied species of Senecio and the characteristic type in plants of Senecio. Other types of sesquiterpenoid compounds were followed by eremophilane (30species20%percentage), eremophil-8,12-olide (28species19%percentage), bisabolane (23species15%percentage), germacrane (20species13%percentage), cacalol (18species12%percentage), eudesmane (14species9%percentage), caryophyllane (8species5%percentage), copane and oplopane (5species3%percentage, individually). In addition, there were13types of sesquiterpenoid compounds existing exclusively in some specific species of Senecio, with each type in a single species, which might be used as the characteristic compound in those species. It showed that types with Eremophilane skeletons were shared by the majority of the Senecio species and were the characteristic types in them.Thus results of cluster analysis can be additional evidences for chemical classification of some species of Senecio, though they can not confirm all relationships among them.Phylogenetic relationship is the important background for understanding the origin and evolution of species and their characters. Intrinsically, the difference of species and their characters can be traced back to gene divergence, which is the divergence of gene structure and the composition of DNA sequence. Thus the DNA sequence is undoubtedly the most direct and reliable evidence to infer the relationship of species. In his study, to explore the relationship between the type of sesquiterpenoid and species evolution we construct a molecular phylogenetic tree based on ITS sequence from three species of Senecio in China combining with other50species which are available in GenBank. using Maximum parsimony. Maximum likelihood and Bayesian analytical methods. In addition, geographical distribution and biogenesis methods were also considered. to explore molecular diversity of sesquiterpenoid compounds and evolutional correlation between compound and morphology. The result showed that the origin and evolution of most sesquiterpenoid compounds had little correlation with the evolution of species. Their occurrences may be much more influenced by environmental factors. Therefore, the characters of sesquiterpenoid compounds have limited value to be the direct evidence to pharmacophylogeny and phytochemical taxonomy. |
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