互花米草黄酮含量分析及其生态学意义

互花米草原产于北美洲大西洋沿岸和墨西哥海湾，经引种和其他原因，已扩散到包括中国在内的多个国家和地区，并对被入侵地生态系统的结构和功能均造成了显著影响。有关该物种的入侵机制和控制策略是当前入侵生态学研究领域的热点。互花米草生物质材料中富含黄酮类物质，与该物种向海扩张的能力可能存在一定联系。鉴于黄酮广泛的应用价值，能否借助黄酮成分的开发带动生物质的收割，以达到有效控制该物种的目的，也是当前研究者所关注的问题。以芦丁为标准参照物，NaNO2-Al（ NO3）3法比较温室互花米草不同器官中总黄酮含量的差异，分析盐城滩涂互花米草越冬芽黄酮含量与所在地理位置之间的关系，采用L9（34）正交试验对干储互花米草叶总黄酮的提取工艺进行优化。互花米草叶片中黄酮类物质远高于根、根状茎、茎、叶鞘、颖稃及种子。盐城滩涂上互花米草越冬芽的黄酮含量随着由陆向海方向基本呈升高趋势。互花米草总黄酮最佳提取工艺为料液比1∶30，乙醇浓度70％，水浴温度80℃，水浴时间2h。互花米草植物材料中，尤其在叶部，黄酮含量十分丰富。该黄酮物质与互花米草在海岸带盐沼生态系统中的适应和向海扩张也存在正相关关系，可作为探索互花米草入侵机制的一个方向。利用本研究中所得优化提取工艺可从互花米草干储生物质中获得稳定的黄酮来源。配合黄酮经济成分的开发而推动生物质材料的收割利用，将成为互花米草生态控制的一项潜在策略。

Flavonoid levels in Spartina alterniflora Loisel (Cyperales: Poaceae) and their ecological significance

Background Spartina alterniflora Loisel, originally distributed along the Atlantic coasts of North America and the Gulf of Mexico, has been introduced into many countries including China , and has often become invasive , causing significant changes in both the structure and functioning of coastal ecosystems .The invasion mechanism and control strategies against this species consti-tute an important problem in current invasion ecology .S.alterniflora is rich in flavonoids , which may explain the fast expansion of the species .Since flavonoids are also of Spartina-originating flavonoids as well as collection of Spartina biomass has been suggested a way of controlling the invasion of the species .Method]Using rutin as standard , total flavonoid concents in different organs of S. alterniflora were compared by reaction with NaNO2 and Al（NO3）3.We also examined the relationship between flavonoids contents in winter shoots and their position in coastal saltmarsh .Using a L9 （34 ） orthogonal test, the extraction method of flavonoids from stored, dry S.alterniflora leaves was also optimized .Result] Leaves of S.alterniflora contain the highest amount of flavonoids , while lower levels were found in roots , rhizomes, stems, leaf sheath, glumes and seeds.Flavonoid contents in winter shoots from coastal saltmarsh decreased as the plants grew further from the sea towards upland .The best extraction method for flavonoids from S. alterniflora involved the following parameters：1∶30 （g∶mL） material∶solvent ratio, using 70%alcohol as solvent, and extraction in water bath at 80 ℃for 2 h.Conclusion and significance]Various parts of S.alterniflora, especially leaves , contain high levels of flavonoids, which may positively correlated with their closeness to the seaside parts of coastal ecosystems .Further research on the role of flavonoids may throw light on the invasion mechanism of S.alterniflora.The value of flavonoids as medicine may stimulate the active harvesting of Spartina biomass, which could become a