Studies On Chemical Composition And Biological Activity Of Citrus Reticulata Blanco Peel Of Different Storage Period And Origins

Objectives:The volatile oil components and representative flavonoids of Citrus reticulata Blanco peel of different storage period and origins were analyzed to evaluate their anti-inflammatory and anti-cancer activities.The correlation between chemical components and biological activities of tangerine peel was analyzed to provide reference data for the identification and quality control standards of of Citrus reticulata Blanco peel of different storage period and origins.Methods:Respectively by using steam distillation and solvent extraction from 21kinds of Citrus reticulata Blanco peel extract the volatile oil and ethyl acetate extract,and GC-MS and HPLC were used respectively to the identification,analysis and comparison are made on the chemical composition,and then through the cell experiment to test its anti-inflammatory and anti-cancer activity,analyze the correlation between chemical composition and bioactivity,and preliminary explore the mechanism of the active ingredient.Results:The Citrus reticulata Blanco peel of Guangdong and Sichuan are rich in volatile oil,The Citrus reticulata Blanco peel of Jiangxi,human,Fujian and Zhejiang Contains too little volatile oil.The S1,S6,S7,S8,S9,and S10（1²5 years）indicates that as the storage time the longer the volatile oil content has a tendency to reduce.Among the 14 volatile oils of orange peel,the most abundant ingredients are Methyl 2-methylamino-benzoate,linalool and trans-limonene,all of which can be used as food flavor.In addition,the volatile oil of Citrus reticulata Blanco peel containsα-Terpineol which can prevent asthma,which may be related to the effect of"regulating qi and strengthening spleen,dampness and eliminating phlegm"of Citrus reticulata Blanco peel in Chinese medicine.Hesperidin,nobiletin,tangeretin and 3,5,6,7,8,3’,4’-heptamethoxyflavone were detected in 21 ethyl acetate extracts.The best anti-inflammatory ethyl acetate extract and volatile oil samples were S16(IC₅₀=10.37μg/mL)and S6（IC50=15.21μg/mL）.The ethyl acetate extracts and volatile oil samples with the best proliferation activity against lung cancer A549 cells are S1（IC50=39.55μg/mL）and S15（IC50=23.69μg/mL）respectively.Four flavonoids contained in ethyl acetate extract were correlated with anti-inflammatory activity and anti-cancer cell proliferation activity and there was a strong correlation between the content of nobiletin and its anti-inflammatory activity.ethyl acetate extract S1 and essential oil sample S11 are showed good activity when the inhibitory effect on A549 cell migration and induce A549 cell apoptosis were assayed.The content of volatile oil in 7 kinds of Citrus reticulata Blanco peel was too low to extract the sample numbers are S12,S13,S14,S18,S19,S20 and S21.Conclusions:Methyl 2-methylamino-benzoate is a unique and rich component in the volatile oil of Citrus reticulata‘Chachi’,which can be used as one of the indexes for quality control of Citrus reticulata‘Chachi’.This study showed that the volatile oil of some volatile oil and the ethyl acetate extract samples had significant effects on the anti-inflammation and anti-cancer cell proliferation,among which the content of nobiletin was significantly correlated with the anti-inflammatory activity,the relationship between the content of nobiletin and the quality and different efficacy of Citrus reticulata Blanco peel could be further studied.At the same time,it is suggested that the content of nobiletin should be determined as one of the indexes for quality control of Citrus reticulata Blanco peel,and the related quality control standards should be established.