J Dent Hyg Sci.  2020 Dec;20(4):213-220. 10.17135/jdhs.2020.20.4.213.

Inhibitory Effects on Oral Microbial Activity and Production of Lipopolysaccharides-Induced Pro-Inflammatory Mediators in Raw264.7 Macrophages of Ethanol Extract of Perilla flutescens (L.) Britton

• Jeong MJ
• Lim DS
• Lee MH
• Heo K
• Kim HH
• Jeong SJ

• KMID: 2510014
• DOI: http://doi.org/10.17135/jdhs.2020.20.4.213

Abstract

Background
The leaves of Perilla frutescens, commonly called perilla and used for food in Korea, contain components with a variety of biological effects and potential therapeutic applications. The purpose of this study was to identify the components of 70% ethanol extracted Perilla frutescens (EEPF) and determine its inhibitory effects on oral microbial activity and production of nitric oxide (NO) and prostaglandin E₂ (PGE₂) in lipopolysaccharides (LPS)-stimulated Raw264.7 macrophages, consequently, to confirm the possibility of using EEPF as a functional component for improving the oral environment and preventing inflammation.
Methods
One kg of P. frutescens leaves was extracted with 70% ethanol and dried at −70^o C. EEPF was analyzed using high-performance liquid chromatography analysis, and antimicrobial activity against oral microorganisms was revealed using the disk diffusion test. Cell viability was elucidated using a methylthiazolydiphenyl-tetrazolium bromide assay, and the effect of EEPF on LPS-induced morphological variation was confirmed through microscopic observation. The effect of EEPF on LPS-induced production of pro-inflammatory mediators, NO and PGE₂ was confirmed by the NO assay and PGE₂ enzyme-linked immunosorbent assay.
Results
The main component of EEPF was rosemarinic acid, and EEPF showed weak anti-bacterial and anti-fungal effects against microorganisms living in the oral cavity. EEPF did not show toxicity to Raw264.7 macrophages and had inhibitory effects on the morphological variations and production of pro-inflammatory mediators, NO and PGE₂ in LPS-stimulated Raw264.7 macrophages.
Conclusion
EEPF can be used as a functional material for improving the oral environment through the control of oral microorganisms and for modulating inflammation by inhibiting the production of inflammatory mediators.

Keyword

Oral microbial activity; Perilla frutescens; Pro-Inflammatory Mediator; Raw264.7 cells; Rosmarinic acid