A Comparative Study on Anti-Aging Effect of Trapa japonica Flerov. Extract (TE) and Enzyme-Modified Extract(EMTE)

In skin, advanced glycation end products (AGEs) creates new residues or formations of cross-links in the extracellular matrix of the dermis. The accumulation of free radicals and AGEs plays a very important role in skin aging. The epicarps of Trapa Japonica Flerov. have strong anti-oxidative activity, but their use is limited because of their poor solubility in water for cosmetics. Enzymatically modified Trapa Japonica Flerov. (EMTE, glycosyl form) are water-soluble modifications which are manufactured by transglycosylation with cyclodextrin glucanotransferase (CGTase). Trapa japonica Flerov. is an annual aquatic plant which has been commercially cultivated for its edible fruits in aquatic areas in the lowlands or lakes in Asia. Total polyphenol was determined by Folin-Ciocalteau colorimetry assay. The total polyphenol content of the TE and EMTE similarly were investigated ranged from 36.3 mg/g and 36.9 mg/g GAE. EMTE showed DPPH radical-scavenging activity similar to EM extract and EMTE extract showed somewhat higher antioxidant activity. (EM SC₅₀=68.5 μg/㎖; EMTE SC₅₀=62.9 μg/㎖). EMTE and TE showed almost no tyrosinase inhibitory activity. EMTE also has Porcine Pancreatic Elastase inhibitory activity similar to TE. EMTE had strong inhibitory activity of D-glucose induced AGE formation (EM IC₅₀=129.5 μg/㎖; EMTE IC₅₀=74.5 μg/㎖; aminoguanidine (positive control), IC₅₀=54.3 μg/㎖). These results suggest that EMTE may work as an anti-skin aging agent by preventing oxidative stress and other complications associated with AGEs formation.