This study aims to optimize the ultrasound-assisted deep eutectic solvent extraction technique of phenolic compounds from Ginkgo biloba leaves, and to explore the relation between their antioxidation and ΔE(LUMO-HOMO) (LUMO: lowest unoccupied molecular orbital, HOMO: highest occupied molecular orbital) values.To do that, deep eutectic solvent (DES) combined with ultrasonic-assisted extraction were successfully constructed by choline chloride as the hydrogen bond acceptor and malic acid, lactic acid, glycerol, glucose, sorbitol, ethylene glycol, or urea as hydrogen bond donors.In this work, the effects of extraction solvent, ultrasound power, extraction time and solid-liquid ratio on the extraction yield of phenolic compounds from G.biloba leaves were explored.The technique of the extraction was successively optimized.The results showed that the optimal conditions were obtained:DES was selected as choline chloride:urea (molar ratio of 1:2), ultrasound power 200 W, solid-liquid ratio 1:20(g:mL), water content of 30% in DES, and ultrasound time 10 min.The extraction yield of phenolic compounds from G.biloba leaves reached 96.70%, which incorporated quercetin, luteolin, caffeic acid, vanillic acid, protocatechuic acid, ferulic acid, chlorogenic acid and rutin, and their contents were 55.32, 129.81, 148.56, 222.03, 237.81, 254.61, 284.40 and 194.79 μg/g, respectively.Also, the antioxidation of phenolic compounds in Ginkgo biloba leaves were evaluated by antioxidant models such as DPPH free radical, ABTS cationic free radical scavenging capacity and oxygen radical absorbance capacity(ORAC).The results showed that quercetin had the strongest capacity on DPPH free radical scavenging (IC50=0.018 1 mg/mL), ABTS cationic free radical scavenging (0.053 8 mg/mL) and ORAC value was 184.68 μmol VC/mg) among these phenolic compounds.Moreover, the ΔE(LUMO-HOMO) value for each phenolic compound was significantly positively correlated with DPPH free radical and ABTS cationic free radical scavenging capacity (IC50 value), but it was not related to the ORAC value.These observations will provide practical and theoretical foundations for the efficient extraction of phenolic compounds from G.biloba leaves and functional foods in antioxidation.
[1] 肖颗星. 我国银杏产业国际竞争力战略研究[D].南京:南京林业大学, 2018.
XIAO K X.2018.Study on international competitiveness of Ginkgo industry in China[D].Nanjing:Nanjing Forestry University, 2018.
[2] EISVAND F, RAZAVI B M, HOSSEINZADEH H.The effects of Ginkgo biloba on metabolic syndrome:A review[J].Phytotherapy Research, 2020, 34(8):1798-1811.
[3] 付佳乐, 耿直, 郭亚敏, 等.银杏叶总黄酮绿色提取工艺及抗氧化活性研究[J].化学与生物工程, 2024, 41(1):40-45.
FU J L, GENG Z, GUO Y M, et al.Green extraction process and antioxidant activity of total flavonoids from Ginkgo biloba leaves[J].Chemistry & Bioengineering, 2024, 41(1):40-45.
[4] QIN H, HU X T, WANG J W, et al.Overview of acidic deep eutectic solvents on synthesis, properties and applications[J].Green Energy & Environment, 2020, 5(1):8-21.
[5] LIU L M, WANG Y T, ZHANG J C, et al.Advances in the chemical constituents and chemical analysis of Ginkgo biloba leaf, extract, and phytopharmaceuticals[J].Journal of Pharmaceutical and Biomedical Analysis, 2021, 193:113704.
[6] DONG Q H, CAO J, WU R, et al.Efficient removal of ginkgolic acids from Ginkgo biloba leaves crude extract by using hydrophobic deep eutectic solvents[J].Industrial Crops and Products, 2021, 166:113462.
[7] ZHANG Y, ZHANG C H, XU C, et al.Effect of geographical location and soil fertility on main phenolic compounds and fatty acids compositions of virgin olive oil from Leccino cultivar in China[J].Food Research International, 2022, 157:111207.
[8] SABIR S M, AHMAD S D, HAMID A, et al.Antioxidant and hepatoprotective activity of ethanolic extract of leaves of Solidago microglossa containing polyphenolic compounds[J].Food Chemistry, 2012, 131(3):741-747.
[9] ZHU K X, LIAN C X, GUO X N, et al.Antioxidant activities and total phenolic contents of various extracts from defatted wheat germ[J].Food Chemistry, 2011, 126(3):1122-1126.
[10] JING P, ZHAO S J, RUAN S Y, et al.Quantitative studies on structure-ORAC relationships of anthocyanins from eggplant and radish using 3D-QSAR[J].Food Chemistry, 2014, 145:365-371.
[11] CHEN D P, WANG H.HOMO-LUMO energy splitting in polycyclic aromatic hydrocarbons and their derivatives[J].Proceedings of the Combustion Institute, 2019, 37(1):953-959.
[12] ŠALIĆ A, BAJO M, CVJETKO BUBALO M, et al.Extraction of polyphenolic compounds from Ginkgo leaves using deep eutectic solvents:A potential solution for the sustainable and environmentally friendly isolation of biflavonoids[J].Industrial Crops and Products, 2024, 219:119068.
[13] SU M, JIN R Y, ZHU J, et al.Investigation of the microstructure and dynamical evolution following gradient hydration of deep eutectic solvent, with application to polyphenol extraction[J].ACS Sustainable Chemistry & Engineering, 2024, 12(5):1884-1896.
[14] GABRIELE F, CHIARINI M, GERMANI R, et al.Effect of water addition on choline chloride/glycol deep eutectic solvents:Characterization of their structural and physicochemical properties[J].Journal of Molecular Liquids, 2019, 291:111301.
[15] SAZALI A L, ALMASOUD N, AMRAN S K, et al.Physicochemical and thermal characteristics of choline chloride-based deep eutectic solvents[J].Chemosphere, 2023, 338:139485.
[16] KALYNIUKOVA A, HOLUŠA J, MUSIOLEK D, et al.Application of deep eutectic solvents for separation and determination of bioactive compounds in medicinal plants[J].Industrial Crops and Products, 2021, 172:114047.
[17] DHEYAB A S, ABU BAKAR M F, ALOMAR M, et al.Deep eutectic solvents (DESs) as green extraction media of beneficial bioactive phytochemicals[J].Separations, 2021, 8(10):176.
[18] WANG P X, CHENG C X, MA Y Q, et al.Degradation behavior of polyphenols in model aqueous extraction system based on mechanical and sonochemical effects induced by ultrasound[J].Separation and Purification Technology, 2020, 247:116967.
[19] ABDEL-MAGEED W M, BAYOUMI S A H, RADWAN A A, et al.Simmondsia chinensis:A rich source of bioactive flavonoids and lignans[J].Industrial Crops and Products, 2014, 60:99-103.
[20] LI X C, CHEN B, XIE H, et al.Antioxidant structure-activity relationship analysis of five dihydrochalcones[J].Molecules, 2018, 23(5):1162.
[21] PLATZER M, KIESE S, TYBUSSEK T, et al.Radical scavenging mechanisms of phenolic compounds:A quantitative structure-property relationship (QSPR) study[J].Frontiers in Nutrition, 2022, 9:882458.
[22] SARANYA M, AYYAPPAN S, NITHYA R, et al.Molecular structure, NBO and HOMO-LUMO analysis of quercetin on single layer graphene by density functional theory[J].Digest Journal of Nanomaterials and Biostructures, 2018, 13(1):97-105.
[23] HU X N, YUAN L, HAN L J, et al.Characterization of antioxidant and antibacterial gelatin films incorporated with Ginkgo biloba extract[J].RSC Advances, 2019, 9(47):27449-27454.
[24] IRFAN A, IMRAN M, KHALID N, et al.Molecular level interaction, HOMO-LUMO, MEP, UV-Vis, Hirshfeld, topological analysis, and in-vitro of isoflavones from Eremostachys vicaryi Benth.Ex Hook.f[J].Journal of Molecular Structure, 2024, 1303:137581.
[25] RODRÍGUEZ-BONILLA P, GANDÍA-HERRERO F, MATENCIO A, et al.Comparative study of the antioxidant capacity of four stilbenes using ORAC, ABTS+, and FRAP techniques[J].Food Analytical Methods, 2017, 10(9):2994-3000.
