Guijie Li1, Yujiao Cheng1, Tenghui Zhang2, Yingzhuo Li3, Leng Han1, Guolu Liang4. 1. Citrus Research Institute, Southwest University, Chongqing, People's Republic of China. 2. Chengdu Centre Testing International Group Co., Ltd., Chengdu, People's Republic of China. 3. Chongqing Beibei Agricultural and Rural Committee, Chongqing, People's Republic of China. 4. College of Horticulture and Landscape Architecture, Southwest University, Chongqing, People's Republic of China.
Abstract
PURPOSE: Citrus essential oils are widely used for aromatherapy and the alternative treatment of chronic diseases. Beyond the aroma substances, they are known to contain bioactive nonvolatile components; however, little knowledge has been gained about nonvolatiles in the essential oil of pomelo (Citrus grandis Osbeck), the largest citrus fruit. The purpose of this study was to analyze the nonvolatile oxygenated heterocyclic compounds (OHCs) of pomelo essential oils and evaluate their in vitro antioxidant activities for further development. METHODS: Cold-pressed essential oil (CPEO) and distilled essential oil (DEO) were obtained from the peel of the Liangping pomelo cultivar. High-performance liquid chromatography (HPLC) coupled with a photodiode array and fluorescence detection method was developed to identify and quantify the OHCs of the two essential oils. Ferric reducing antioxidant power and 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2-phenyl-4,4,5,5-tetramethyl-imidazoline-1-oxyl 3-oxide (PTIO) radical scavenging assays were used to determine the antioxidative capabilities. RESULTS: Thirteen OHCs were identified in CPEO. Coumarins such as meranzin (2.0 mmol L-1) and furanocoumarins such as isoimperatorin (1.3 mmol L-1) composed the majority of nonvolatiles in CPEO. These OHCs were characterized by high proportion (58%) of side chain epoxides. Five OHCs, namely, auraptenol, 6',7'-dihydroxybergamottin (6',7'-DHB), imperatorin, isoimperatorin and 8-geranyloxypsoralen were first identified in pomelo CPEO. Eight OHCs were detected at trace amounts in pomelo DEO. Antioxidant assays showed that CPEO was multiple times more potent than DEO regarding the total reducing power and radical scavenging capacity. Clearance of PTIO, a stable reactive oxygen species, followed slow kinetics. CONCLUSION: Coumarins and furanocoumarins, two families of OHCs, constituted most of the nonvolatile components in CPEO. The nonvolatiles contributed significantly to the in vitro antioxidant activity of CPEO. Pomelo CPEO showed good prospects as a potential long-lasting natural antioxidant.
PURPOSE: Citrus essential oils are widely used for aromatherapy and the alternative treatment of chronic diseases. Beyond the aroma substances, they are known to contain bioactive nonvolatile components; however, little knowledge has been gained about nonvolatiles in the essential oil of pomelo (Citrus grandis Osbeck), the largest citrus fruit. The purpose of this study was to analyze the nonvolatile oxygenated heterocyclic compounds (OHCs) of pomelo essential oils and evaluate their in vitro antioxidant activities for further development. METHODS: Cold-pressed essential oil (CPEO) and distilled essential oil (DEO) were obtained from the peel of the Liangping pomelo cultivar. High-performance liquid chromatography (HPLC) coupled with a photodiode array and fluorescence detection method was developed to identify and quantify the OHCs of the two essential oils. Ferric reducing antioxidant power and 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2-phenyl-4,4,5,5-tetramethyl-imidazoline-1-oxyl 3-oxide (PTIO) radical scavenging assays were used to determine the antioxidative capabilities. RESULTS: Thirteen OHCs were identified in CPEO. Coumarins such as meranzin (2.0 mmol L-1) and furanocoumarins such as isoimperatorin (1.3 mmol L-1) composed the majority of nonvolatiles in CPEO. These OHCs were characterized by high proportion (58%) of side chain epoxides. Five OHCs, namely, auraptenol, 6',7'-dihydroxybergamottin (6',7'-DHB), imperatorin, isoimperatorin and 8-geranyloxypsoralen were first identified in pomelo CPEO. Eight OHCs were detected at trace amounts in pomelo DEO. Antioxidant assays showed that CPEO was multiple times more potent than DEO regarding the total reducing power and radical scavenging capacity. Clearance of PTIO, a stable reactive oxygen species, followed slow kinetics. CONCLUSION: Coumarins and furanocoumarins, two families of OHCs, constituted most of the nonvolatile components in CPEO. The nonvolatiles contributed significantly to the in vitro antioxidant activity of CPEO. Pomelo CPEO showed good prospects as a potential long-lasting natural antioxidant.
Authors: Marian Valko; Dieter Leibfritz; Jan Moncol; Mark T D Cronin; Milan Mazur; Joshua Telser Journal: Int J Biochem Cell Biol Date: 2006-08-04 Impact factor: 5.085
Authors: Poliana D Gurak; Adriana Z Mercadante; M L González-Miret; Francisco J Heredia; Antonio J Meléndez-Martínez Journal: Food Chem Date: 2013-10-01 Impact factor: 7.514
Authors: Nesrin M Fayek; Mohamed A Farag; Azza R Abdel Monem; Mohamed Y Moussa; Samia M Abd-Elwahab; Nebal D El-Tanbouly Journal: J Chromatogr Sci Date: 2019-04-01 Impact factor: 1.618
Authors: Weiyi Sun; Megan S Rice; Min K Park; Ock K Chun; Melissa M Melough; Hongmei Nan; Walter C Willett; Wen-Qing Li; Abrar A Qureshi; Eunyoung Cho Journal: J Nutr Date: 2020-06-01 Impact factor: 4.798