title: Effects of storage period and heat treatment on phenolic compound composition in dried Citrus peels (Chenpi) and discrimination of Chenpi with different storage periods through targeted metabolomic study using HPLC-DAD analysis.
abstract: Dried Citrus peels, known as Chenpi in Chinese medicine, are a traditional medicine for the treatment of indigestion and inflammatory syndromes. In this study, we evaluated the effect of storage periods (1-year vs. 3-year) and heat treatment (90min vs. 3h at 120°C) on the total phenolic content (TPC) and bioactivity (anti-oxidant activity) of Chenpi. It was found that the long-term stored Chenpi had a higher TPC and superior 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity levels compared to the regular stored Chenpi, and that heat treatment increased both TPC and bioactivity. Subsequently, we developed and validated a high performance liquid chromatography with diode-array detection (HPLC-DAD) method to determine individual phenolic acids. Eleven phenolic compounds were determined in different Chenpi samples. Concentrations of total phenolic compounds were higher in long-term stored Chenpi and heat treatment raised the levels of those in regular stored Chenpi. In further study, a targeted metabolomic approach was applied to discriminate Chenpi with different storage periods. Two different phenolic acid fractions (free and ester) from the regular and long-term stored Chenpi were analyzed using the developed HPLC-DAD and the data were used in principal component analysis (PCA) on the HPLC-DAD peak areas of the 11 phenolic acids. Two principal components (PC1 and PC2) accounted for 87.1% of the variation between the regular and long-term stored Chenpi. In a two-dimensional plot of PC1 and PC2, the samples divided into four groups: two storage periods and two fractions.
authors.affiliation: College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, Republic of Korea.
authors.forename: Moon-Young
authors.initials: MY
authors.lastname: Choi
authors.forename: Chuan
authors.initials: C
authors.lastname: Chai
authors.forename: Jeong Hill
authors.initials: JH
authors.lastname: Park
authors.forename: Johan
authors.initials: J
authors.lastname: Lim
authors.forename: Jeongmi
authors.initials: J
authors.lastname: Lee
authors.forename: Sung Won
authors.initials: SW
authors.lastname: Kwon
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000737:chemistry* / Q000494:pharmacology; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D005591:Chemical Fractionation; D002851:Chromatography, High Pressure Liquid; D002934:Cinnamates / Q000032:analysis* / Q000494:pharmacology; D002957:Citrus / Q000737:chemistry*; D004356:Drug Storage; D004365:Drugs, Chinese Herbal / Q000737:chemistry* / Q000494:pharmacology*; D005638:Fruit / Q000737:chemistry*; D057166:High-Throughput Screening Assays; D006358:Hot Temperature; D057230:Limit of Detection; D016877:Oxidants / Q000037:antagonists & inhibitors / Q000633:toxicity; D010636:Phenols / Q000032:analysis* / Q000494:pharmacology; D025341:Principal Component Analysis; D011786:Quality Control; D013552:Swine; D013997:Time Factors
chemical_list: D000975:Antioxidants; D002934:Cinnamates; D004365:Drugs, Chinese Herbal; D016877:Oxidants; D010636:Phenols; C557482:chenpi