[Objectives] To determine the optimal extraction technology of flavonoids in Dendranthema indicum,and analyze the antioxidant activity of total flavonoids in D. indicum. [Methods]D. indicum was used as raw material to...[Objectives] To determine the optimal extraction technology of flavonoids in Dendranthema indicum,and analyze the antioxidant activity of total flavonoids in D. indicum. [Methods]D. indicum was used as raw material to extract the total flavonoids by water extraction,alcohol extraction,freeze-thaw,microwave assisted extraction and ultrasonic extraction. [Results]Microwave assisted extraction had the highest extraction rate. Therefore,the microwave assisted extraction was selected as the main method,the ethanol aqueous solution was used as the solvent,and the single factor experiment was carried out with microwave power,ethanol volume fraction,solid-to-liquid ratio and microwave time as the variables. The optimal extraction process of flavonoids was microwave power 400 W,solid-to-liquid ratio 1 ∶ 30,extraction time60 s,ethanol volume fraction 70%,under this condition,the extraction yield was 10. 65 mg/g. The antioxidant activity of flavonoids in D. indicum was determined. The results showed that the highest scavenging rate of DPPH·free radicals was 47. 89%,and the highest scavenging rate of hydroxyl radicals was 98. 00%. [Conclusions]The flavonoids in D. indicum have excellent antioxidant activity. This study is expected to provide a basis for further development of D. indicum products.展开更多
Phylogenetic relationships of the different species in the genus Dendranthema (DC.) Des Moul. were estimated based on chromosome fluorescent in situ hybridization (FISH) with 18S-26S rDNA of Arabidopsis and genomic DN...Phylogenetic relationships of the different species in the genus Dendranthema (DC.) Des Moul. were estimated based on chromosome fluorescent in situ hybridization (FISH) with 18S-26S rDNA of Arabidopsis and genomic DNA of Dendranthema as probes. The results revealed that there was no positive correlation between the number of nuclear organization region (NOR) loci and the ploidy of Dendranthema. The exact cytogenetic information of NORs about 14 operational taxonomic units (OTUs) indicated that D. vestitum (Hemsl.) Ling et Shih was closer to the cultivars than other putative species, whereas D. zawadskii (Herb.) Tzvel. was the most distinct. The ambiguously distributed signals of genomic in situ hybridization (GISH) with genomic DNA of lower ploidy species as probes suggested that different genomes among Dendranthema were mixed. The result also indicated the limitation of GISH in studies on the phylogenetic relationships of the different species in this genus Dendranthema and on the origin of cultivated chrysanthemums. Based on these results and previous research, the origin of Chinese cultivated chrysanthemum is discussed.展开更多
基金Supported by Qing Lan Project of Universities in Jiangsu Province(2016)Brand Discipline Construction Project of Universities in Jiangsu Province(PPZY2015B179)+1 种基金Development Project for Biomass Green Fuel and Chemical Key Laboratory of Jiangsu Province(JSBGFC12010)Excellent Scientific and Technological Innovation Team of Universities in Jiangsu Province(2017-31)
文摘[Objectives] To determine the optimal extraction technology of flavonoids in Dendranthema indicum,and analyze the antioxidant activity of total flavonoids in D. indicum. [Methods]D. indicum was used as raw material to extract the total flavonoids by water extraction,alcohol extraction,freeze-thaw,microwave assisted extraction and ultrasonic extraction. [Results]Microwave assisted extraction had the highest extraction rate. Therefore,the microwave assisted extraction was selected as the main method,the ethanol aqueous solution was used as the solvent,and the single factor experiment was carried out with microwave power,ethanol volume fraction,solid-to-liquid ratio and microwave time as the variables. The optimal extraction process of flavonoids was microwave power 400 W,solid-to-liquid ratio 1 ∶ 30,extraction time60 s,ethanol volume fraction 70%,under this condition,the extraction yield was 10. 65 mg/g. The antioxidant activity of flavonoids in D. indicum was determined. The results showed that the highest scavenging rate of DPPH·free radicals was 47. 89%,and the highest scavenging rate of hydroxyl radicals was 98. 00%. [Conclusions]The flavonoids in D. indicum have excellent antioxidant activity. This study is expected to provide a basis for further development of D. indicum products.
文摘Phylogenetic relationships of the different species in the genus Dendranthema (DC.) Des Moul. were estimated based on chromosome fluorescent in situ hybridization (FISH) with 18S-26S rDNA of Arabidopsis and genomic DNA of Dendranthema as probes. The results revealed that there was no positive correlation between the number of nuclear organization region (NOR) loci and the ploidy of Dendranthema. The exact cytogenetic information of NORs about 14 operational taxonomic units (OTUs) indicated that D. vestitum (Hemsl.) Ling et Shih was closer to the cultivars than other putative species, whereas D. zawadskii (Herb.) Tzvel. was the most distinct. The ambiguously distributed signals of genomic in situ hybridization (GISH) with genomic DNA of lower ploidy species as probes suggested that different genomes among Dendranthema were mixed. The result also indicated the limitation of GISH in studies on the phylogenetic relationships of the different species in this genus Dendranthema and on the origin of cultivated chrysanthemums. Based on these results and previous research, the origin of Chinese cultivated chrysanthemum is discussed.
