(LB03-13-24) Investigation of Antioxidant and Anti-aging Activity of Ethyl Acetate Fraction of Houttuynia cordata and Identification of Quercitrin As Main Ingredient

Objectives: This study was carried out to evaluate the in vitro antioxidant activity of extracts and fractions of Houttuynia cordata(HC) and the in vivo antioxidant and anti-aging functionality using Caenorhabditis elegans(C.elegans) as a model, and to isolate functional components in the ethyl acetate(EA) fraction of the HC based on the experimental results.

Methods: HC was extracted with methanol and fractionated according to solvent polarity (n-hexane, methylene chloride, ethyl acetate, n-butanol). The radical scavenging activities of the extracts and fractions were evaluated in vitro, and the antioxidant and anti-aging indicators such as antioxidant enzyme activity, inhibition of reactive oxygen species, oxidative stress resistance, heat stress resistance, heat shock protein expression, aging pigment accumulation, and life extension level in vivo were evaluated using C.elegans as a model. The separation of functional substances in the EA fraction of HC was performed using a silica gel column. The obtained substances were purified using a sephadex LH-20 column, and the structure was identified using NMR spectroscopy.

Results: The EA fraction of HC showed the highest radical scavenging activity and had the highest polyphenol and flavonoid contents. The EA fraction of HC increased the activity of antioxidant enzymes in nematodes in a concentration-dependent manner and significantly suppressed the amount of reactive oxygen species generated. It showed resistance to oxidative stress and heat stress, increasing the survival rate, inhibiting the accumulation of aging pigments, and increasing the expression level of SOD-3::GFP and HSP-16.2::GFP. The EA fraction of HC significantly extended the lifespan of nematodes, and as a result of separating the EA fraction, it was confirmed that it was quercetin 3-O-a-L-rhamnoside(Quercitrin), known as the main component of HC.

Conclusions: Considering these results, it is believed that HC can help improve indicators related to antioxidants, anti-aging, and lifespan extension, and its main functional ingredient is judged to be Quercitrin. In the future, if antioxidant and anti-aging efficacy is evaluated at the single substance level, more accurate functional substance information will be obtained.

Funding Sources: None