Variability of total phenolic content and main phenolic compounds in the germplasm collections of Perilla frutescens leaves

Perilla plant is an important source of bioactive compounds with potential pharmacological properties. In this study, we evaluated the total phenolic content (TPC) and profiles of major phenolic contents of perilla leaves in 762 germplasm collections. TPC was estimated using Folin–Ciocalteu method [1]. Rosmarinic acid (RA), Caffeic acid (CA), pigenin-7-O-diglucoronide (ADG), scutellarein-7-O-glucoronide (SG), and apigenin-7-O-glucoronide (AG) were analyzed by using Ultra Performance Liquid Chromatography (UPLC) equipped with PDA detector. The TPC and individual phenolic compounds showed a wide variation across the entire germplasm collections. TPC was ranged from 9.87 to 133.69 mg GAE  / g dried extract (DE). RA, CA, ADG, SG, and AG were ranged from 0.27 to 21.05 mg / g, 0.08 to 1.16 mg / g, 0.00 to 2.18 mg LUE / g, 0.20 to 5.25 mg LUE / g, and 0.00 to 2.81 mg LUE / g of DE, respectively. Based on the surface and back color of the leaves, samples were divided into seven groups (A, B, C, D, E, F and G). Group C showed higher AG than other groups. While samples in group E were characterized by higher values of TPC, RA, and SG compared to other groups. Group G contained samples with higher value of CA and ADG relative to the other groups (p>0.05). Accessions IT226732, IT226741, IT274300 and IT274302 could be utilized in research and food processing industries for developing new functional materials with high content of phenolic compounds.

• References

• 1 Waterhouse AL. Determination of total phenolics. In: Wrolstad RE. , ed. Current protocols in food analytical chemistry. New York, USA: John Wiley & Sons Inc.; 2002: 1-4