Microwave Extraction and Content Determination of Total Flavonoids in Schizonepeta tenuifolia (Benth) Briq. Leaves during Different Growing Periods
Abstract:ObjectiveIn order to make clear the proper harvest time when Contain maximum active ingredients in leaves of Schizonepeta tenuifolia. The contents of total flavonoids in leaves of schizonepeta tenuifolia was extracted during different growing periods.MethodsContents of tofal flavonoids were determined by spectrophotometry.ResultsThe tontents of total flavonoids in leaves was between 12.140 and 22.000 mg/g from July to October. with the min mum content of 12.140 mg/g in August,and increasing to the maximum content of 22.000 mg/g in September. Then after the contents of total flavonoids inleaves decrease again. and reacheol 19.951 mg/g on October 9th.ConclusionThe contents of total flavonoids in leaves of Schizonepeta tenifolia were different and changed regularly depending on the growing period. The appropriated harvest time, therefore should be in September.
Key words:Microwave extraction; Harvest time; Schizonepeta tenuifolia; Leaf; Contents of total flavonoids
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