Planta Med 2014; 80 - P2P26
DOI: 10.1055/s-0034-1394861

Antioxidant activities and polyphenol content of Morus alba leaf extracts collected from varying regions

DS Kim 1, SH Kim 2, GJ Lee 3, HK Kim 1
  • 1Herbal Medicine Resources Group, Korea Institue of Oriental Medicine, Korea
  • 2Institute of Traditional Medicine and Bioscience in Daejeon University, Korea
  • 3Department of Horticulture, Chungnam National University, Korea

Morus alba leaf (MAL), also known as Mori folium when used as a herbal medicine, has traditionally been used in Chinese medicine to treat diabetes, protect the liver and lower blood pressure. A previous study has shown that the butanol extract of MAL and isoquercitrin is able to scavenge the 2,2diphenyl1picrylhydrazyl (DPPH) radical and inhibited oxidation of rabbit and human low-density lipoprotein [1]. The levels of the main antioxidative components of MAL, reported [2]. However, the antioxidant activity, the polyphenol content and the levels of the antioxidants in MAL have not been reported according to collection area. In the present study, MAL was collected from various regions in Korea and the antioxidant activity, total polyphenol contents and main flavonoid contents was investigated. The total polyphenol contents were evaluated based on the FolinCiocalteu method [3] using a spectrophotometer. The total polyphenol contents of the MAL extracts varied between 23.2 and 55.4 mg gallic acid equivalent/g. The antioxidant activities were determined by a 2,2diphenyl1picrylhydrazyl radical scavenging assay method [4]. The radical scavenging activity (SC50) of the MAL extracts ranged between 584 and 139 µg/ml. The identification and quantification of three main polyphenol constituents was performed using HPLC/DAD. A Phenomenex Luna C18 column (250·4.6 mm; particle size, 5 µm) was used, and the mobile phase was composed of 0.1% (v/v) trifluoroacetic aqueous solution (A) and acetonitrile (B). At 0 min, the mobile phase consisted of 85% A/15% B and was held for 30. The average of the total flavonol compounds (rutin, isoquercitrin and astragalin) was 9.52 mg/g, which was similar to that of commercial MAL extracts (10.58 mg/g).

Keywords: Morus alba leaf, Mori folium, antioxidant, polyphenol, QC markers

References:

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