The Isolation,Identification And Antioxidant Activity Analysis Of Ethanol Extracts From The Fruit Of Sorbus Pohuashanensis On Mount Tai

Sorbus pohuashanensis,belongs to Sorbus L.Rosaceae,is a kind of deciduous tree.As for a wild resources,it is very abundant and widely distributed.The fruit is beautiful and suitable for appreciation.A reports confirmed that the flavonoid content in the fruit of Sorbus pohuashanensis ranks first among 11 kinds of berries in cold regions.Sorbus plants contain a variety of bioactive components,which have significant effects on antioxidation,bacteriostasis,anti-tumor,etc.However,the fruit of Sorbus pohuashanensis has not been developed and utilized,resulting in wasting of resources.Therefore,it is very urgent to study,develop and utilize the fruit of Sorbus pohuashanensis.The main purpose of this paper is to further explore its utilization value by extracting and purifying the main active components in the ethanol extract of Sorbus pohuashanensis fruit and analyzing its chemical structure,so as to lay a foundation for its early development and utilization.The main research contents and experimental conclusions of this paper are as follows:1.ultrasonic-assisted extraction of flavonoids and other major active substances such as organic acids from the fruit of Sorbus pohuashanensis.Taking ethanol concentration,solid-liquid ratio,ultrasonic temperature and ultrasonic power as single factor conditions,a four-level and four-factor orthogonal experiment was designed.The optimal extraction process for single factor experiment:ethanol concentration80%,solid-liquid ratio 1:5,ultrasonic temperature 50?,ultrasonic power 320W.The optimal extraction process of orthogonal test:ethanol concentration 80%,solid-liquid ratio 1:5,ultrasonic temperature 50?,ultrasonic power 320W.Under these conditions,the yield of total flavonoids was 26.1 mg·g^-1.2.under the condition of keeping flavone species as much as possible,the ethanol extract from the fruit of Sorbus pohuashanensis was purified.Through static adsorption and static analysis experiments,the best purification resin was selected as macroporous resin LSA-4.Through different concentrations?10%-90%?of ethanol elution and TLC detection,the best ethanol elution concentration was 50%.3.Through the experiments on hydroxyl radical scavenging rate and DPPH radical scavenging rate of the ethanol extract from the fruit of Sorbus pohuashanensis,it is concluded that it has good antioxidant activity.within the concentration range for the experiment,the antioxidant activity increases with the increase of the concentration of the extract solution.4.Through TLC detection of the crude ethanol extracts from the fruits of four species of Sorbus pohuashanensis,it was found that the flavonoid species were different,and the flavonoid species of the same plant in different years and in the same season were also different,thus it was concluded that the flavonoid species in the fruits of Sorbus pohuashanensis were varied,and the possible reasons were genotype and environmental impact.Due to different types of flavonoids,their pharmacological values may also differ.5.By using HPLC,preparative HPLC,MS,NMR and other techniques on the purified ethanol extract from the fruit of Sorbus pohuashanensis,three main chemical substances were identified as 3-O-Caffeoylquinic acid?chlorogenic acid?,5-O-Caff-eoylquinic acid?neochlorogenic acid?and prunasin.Experiments prove that the fruit of Sorbus pohuashanensis is rich in chlorogenic acid and neochlorogenic acid,which provides theoretical guidance for extracting natural products from the fruit of Sorbus pohuashanensis.It also provides a method for the research and utilization of chlorogenic acid and neochlorogenic acid in the fruit of Sorbus pohuashanensis.