Purification of Houttuynia cordata Thunb. Essential Oil Using Macroporous Resin Followed by Microemulsion Encapsulation to Improve Its Safety and Antiviral Activity

Abstract

Essential oil extracted from Houttuynia cordata Thunb. (H. cordata) is widely used in traditional Chinese medicine due to its excellent biological activities. However, impurities and deficient preparations of the essential oil limit its safety and effectiveness. Herein, we proposed a strategy to prepare H. cordata essential oil (HEO) safely and effectively by combining the solvent extraction and the macroporous resin purification flexibly, and then encapsulating it using microemulsion. The extraction and purification process were optimized by orthogonal experimental design and adsorption-desorption tests, respectively. The average houttuynin content in pure HEO was then validated at 44.3% ± 2.01%, which presented a great potential for industrial application. Subsequently, pure HEO-loaded microemulsion was prepared by high-pressure homogenization and was then fully characterized. Results showed that the pure HEO-loaded microemulsion was successfully prepared with an average particle size of 179.1 nm and a high encapsulation rate of 94.7%. Furthermore, safety evaluation tests and in vitro antiviral testing indicated that the safety and activity of HEO were significantly improved after purification using D101 resin and were further improved by microemulsion encapsulation. These results demonstrated that the purification of HEO by macroporous resin followed by microemulsion encapsulation would be a promising approach for industrial application of HEO for the antiviral therapies.

Antiviral Effects of Houttuynia cordata Polysaccharide Extract on Murine Norovirus-1 (MNV-1)—A Human Norovirus Surrogate

“…In this study, the antiviral effects of HP and HWE reduced the residual MNV-1 infectivity following 10 min of incubation; therefore, these extracts interact immediately with the virus. The use of these extracts entails no safety concerns because H. cordata is a permitted food additive in China [32]. Our findings support the use of HP and HWE as nontoxic agents.…”

Chemical Composition and Allelopathic, Antibacterial, Antifungal, and Antiacetylcholinesterase Activity of Fish‐mint (Houttuynia cordataThunb.) from India

“…Therefore, 2-undecanone is used as the primary indicator for the quality of H. cordata essential oil. [20] [21] Allelopathic Activity of the Essential Oils…”

Preparation of Vitexin Nanoparticles by Combining the Antisolvent Precipitation and High Pressure Homogenization Approaches Followed by Lyophilization for Dissolution Rate Enhancement

“…Standard methods employed for the preparation of nanoparticles can be basically classified into top-down and bottom-up techniques [ 12 ]. In top-down methods, nanoparticles are produced by breaking down the large particles to smaller particle sizes by mechanical attrition such as high pressure homogenization (HPH) and wet milling [ 13 , 14 , 15 ]. Although the top-down approaches are useful on the commercial front, these processes suffer from certain drawbacks like high energy costs, time-consuming and broad particle size distributions [ 16 , 17 ].…”