Background
In Thai traditional history, Ya-Kao (YK) is a traditional medicine used to relieve fever. Several Thai folk healers have recommended the use of YK for COVID-19 during pre-treatment, treatment, and post-treatment. The Department of Thai Traditional and Alternative Medicine (DTAM) has accepted YK for COVID-19-infected patients and has been observing its effectiveness in a clinical study. Fourteen plants are the main raw materials of the YK formula, which currently lacks scientific information to support its properties. The study aims to investigate the chemical profile of YK and its biological properties by measuring the antibacterial and anti-inflammatory effects, in vitro study.
Methods
YK investigated the chemical profile of the formula based on the raw plant materials by using High-Performance Thin Layer Chromatography (HPTLC). In vitro, the antibacterial activity was conducted by agar disc diffusion and TLC-bioautography. The anti-inflammatory activity was conducted by nitric oxide (NO) production assay in RAW 264.7 macrophages which the inflammatory effect was induced by lipopolysaccharide (LPS).
Results
This study successfully explores the HPTLC method for analyzing the quality of YK raw materials. Whereas the pharmacological property of YK is examined. YK-lime juice extract exhibits the most effective antibacterial activity against both gram-positive and gram-negative bacteria. In addition, the methanolic extract of YK inhibited Streptococcus pyogenes and Klebsiella pnuemoniae by the TLC-bioautography method. Furthermore, YK extracts of methanol, water, and lime juice demonstrate significant anti-inflammatory properties, evidenced by a notable reduction in NO production in a macrophage model induced by LPS.
Conclusions
Overall, these pharmacological data could support the property of YK, a Thai Traditional medicine. It may be consumed to reduce inflammation and antibacterial co-infection not only for COVID-19 but also for other respiratory infections.