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In this seminar I will briefly introduce about current research progress in our Lab related with glycoside synthesis using glycansucrases and carbohydase inhibitor screening using Grid. We are synthesizing various glycosides of the hydroquinone for the improvement of antioxidant activity. Hydroquinone (HQ) functions as a skin whitening agent, but it has the potential to cause dermatitis. We synthesized a novel HQ fructoside (HF), HQ galactoside and HQ glucoside as potential skin whitening agents by reacting glycansucrases from Leuconostoc mesenteroides with HQ as an acceptor and sucrose as a donor. The product was purified using butanol partition and silica-gel column chromatography. One of them HF synthesis was determined using a response surface methodology and the final optimum condition was 350-mM HQ, 115-mM sucrose, and 0.70 U/ml levansucrase, and the final HF produced was 1.09 g/l. HF showed anti-oxidation activities and inhibition against tyrosinase. The IC50 of DPPH scavenging activity was 5.83-mM, showing higher anti-oxidant activity compared to β-arbutin (IC50 = 6.04-mM). The Ki value of HF (0.67-mM) against tyrosinase was smaller than that of β-arbutin (Ki = 2.8-mM). The inhibition of lipid peroxidation by HF was 108.12% that of HQ (100%) and much higher than that of β–arbutin (0.81% of HQ). Virtual screening (VS) was applied for discovery of new inhibitors for the human intestinal maltase (HMA) enzyme. VS of 308 307 compounds was performed with HMA using 4700 CPUs and AutoDock 3.0.5 in a WISDOM (Wide In Silico Docking On Malaria) production environment. The 42 best ranked compounds containing hydrogen bond interaction with key residues from VS were tested in vitro for their inhibitory activities against the recombinant HMA from Pichia pastoris. Compounds 17 and 18 were identified as competitive inhibitors for enzyme inhibition with Ki values of 19.8 and 19.6 μM, respectively. In contrast to acarbose, the two compounds showed no inhibition on human pancreatic α-amylase, suggesting potential inhibitors with fewer side effects, including abdominal discomforts.