ABSTRACT
A method was established for content determination of two kinds of phenolic acids, including rosmarinic acid)(RA) and caffeic acid(CA), and six kinds of flavonoids including scutellarein-7-O-diglucuronide(SDG), luteolin-7-O-diglucuronide(LDG), apigenin-7-O-diglucuronide(ADG), scutellarin-7-O-glucuronide(SG), luteolin-7-O-glucuronide(LG), and apigenin-7-O-glucuronide(AG) in Perilla frutescens leaves. The content of eight chemical components was measured based on ten P. frutescens germplasms of different chemotypes of volatile oil, different cultivated years, and different harvesting periods. The results showed that there was a great difference between the two kinds of constituents of different germplasms. The total content of the two phenolic acids was 2.24-34.44 mg·g~(-1), and the total content of the six flavonoids was 11.55-34.71 mg·g~(-1). Then according to content from most to least, the order of each component was RA(2.13-33.97 mg·g~(-1)), LDG(1.31-14.80 mg·g~(-1)), SG(1.97-8.45 mg·g~(-1)), ADG(2.68-7.60 mg·g~(-1)), SDG(1.16-5.87 mg·g~(-1)), LG(0.78-1.91 mg·g~(-1)), AG(0.56-1.00 mg·g~(-1)), and CA(0.11-0.68 mg·g~(-1)). The chemical contents of the 5 PA-type germplasms in 2017 were mostly higher than those in 2018 showing a large variation with the cultivation years. These contents of two kinds of phenolic acids of 9 germplasms fluctuated with the harvesting time. The content decreased before early flower spike(the 3~(rd) to 18~(th) in August) at first and began to increase in flowering and fruiting period(the 18~(th) in August to 2~(nd) in September). However, these contents had slowly decreasing trend after 2~(nd) in September till 17~(th) in the same month. Interestingly, the content raised again in the maturity of fruits. The variation tendency of contents in six kinds of flavonoids components was inconsistent in different germplasms with the variation of harvesting time. The content of flavonoids in part of germplasms was negatively correlated with the fluctuation of phenolic acids. There was no correlation between phenolic acids and chemical type of the volatile oil. This paper may provide a reference for the high-quality germplasm of P. frutescens cultivation.
Subject(s)
Flavonoids , Oils, Volatile , Perilla frutescens , Phenols , Plant LeavesABSTRACT
Objective:To establish a method for qualitative analysis of components in Perilla frutescens leaves and stalks by liquid chromatography-mass spectrometry (LC-MS)，so as to explore the substance basis of pharmacodynamics differences between P.frutescens leaves and stalks.Method:P. frutescens leaves and stalks were extracted by 80% methanol-water ultrasound. The samples were analyzed by UPLC-Q-Exactive-Orbitrap-MS comprehensively. Halo-C18 column (2.1 mm×100 mm，2.7 μm) was used for gradient elution with 0.05% formic acid aqueous-0.05% acetonitrile formate as mobile phase in positive and negative ion modes. The flow rate was 0.3 mL·min-1，the column temperature was 40 ℃，and the injection volume was 5 μL.Result:The chemical compound in P. frutescens was deduced and identified based on the retention time of chromatography，and the exact molecular weight，excimer ion peaks，fragment ions and reference materials in Xcalibur software. The chemical composition of P. frutescens was identified by Mass Frontier 7.0 software. Totally 4 amino acids，7 phenylpropanoids，10 flavonoids，12 triterpenoids，7 organic acids，4 fatty acids，10 unknown compounds and 54 compounds were identified. Among them，6 triterpene acids, including glochidone, were identified in P. frutescens for the first time. The structures of five characteristic compounds were analyzed. There were 45 constituents in P.frutescens leaves and 32 constituents in P. frutescens stalks. They had 23 common constituents.Conclusion:LC-MS can identify the components of P. frutescens rapidly and effectively. This study provides an important theoretical basis for the quality control of different parts of P. frutescens and the development and utilization of P. frutescens.
ABSTRACT
Objective: To establish an HPLC method for the simultaneous determination of cafferic acid and rosmarinic acid in Perilla frutescens leaves and Schizonepeta tenuifolia. Methods: The anaiysis was carried out on an Agilent C18 column (250 mm × 4.6 mm, 5 μm), and the mobile phase was composed of actonitrile and 0.1% phosphoric acid aqueous with gradient elution. The detection wavelength was 327 nm. The flow rate 1.0 mL/min at column temperature of 30 ℃. Results: Under the chromatographic condition, cafferic acid and rosmarinic acid were completely separated and other components had no effect on their determination. It showed a good linearity in the range of 0.69-22.12 and 3.65 -116.92 μg/mL. The average recoveries of P. frutescens leaves were 102.9% and 105.6%, and the RSD values were 1.8% and 1.9%. The average recoveries of S. tenuifolia were 101.2% and 101.0% and the RSD values were 2.4% and 1.9%. Conclusion: The established method is rapid, sensitive, accurate, and the test component peak separation degree is good, and could be used for the simultaneous determination of cafferic acid and rosmarinic acid in P. frutescens leaves and S. tenuifolia, which provides a scientific basis for the quality evaluation of P. frutescens leaves and S. tenuifolia.