| FASâ… and FASâ…¡are two types of fatty acid synthase (FAS, E.C.2.1.3.85) innature. It has been reported that FASâ… was the potential target for anti-cancer andanti-obesity, and that the inhibitors of FASâ…¡(FabG) were expected to be employed asantibacterial drugs. 3T3-L1 cell is the shape of precursors of the lipocyte, and inhibitedits polarization can reduce the lipocyte.Sichuan brick tea (Kangzhuan) is a kind of the brick tea in China. This papermainly studied the reversible and irreversible inhibitory effect of brick tea on FAS,inhibited dynamics characteristic of FASâ… , the best extraction conditions of brick tea,the efficiency of extraction by the boiling water, inhibited 3T3-L1 cell polarization etc,and carried on the correlative analysis and discussion. The experimental results areshown as follows:1. The optimal solvent for extracting FASâ… inhibitors is 50ï¼…ethanol. Theextraction achieved during 2～3 hours in room temperature, the same as green tea andblack tea. But the extracted effect is better than green tea and black tea by water, andthe temperature of water is higher, the effect is better;2. The boiling water could extract about 29ï¼…effective FAS inhibitors by the firstextraction in 1 hour, and the second times is similar, so it could extract over 50ï¼…inhibitors by two times. It has doubled extracted effect on green tea;3. Sichuan brick tea can inhibit the FASâ… , the inhibitions are different by bricktea in different years. The worst inhibited effect is the sample in 1972 (its IC50 is only14.85μg/ml), the best is the sample in 2001 (IC50 is 5.31μg/ml);4. The inhibition still included the irreversible process by the extracts of bricktea on FASâ… . Its level of deactivation rate constants respectively is 0.127 (min.mgtea/ml)-1 (fast process) and 12.1×10-3 (min.mg tea/ml)-1 (slow process). It inhibitedthe ketoacyl reduction of FASâ… is not obvious, which indicated that the ketoacylreductase domain is not the main reacted site that brick tea extracts attracted.5. The brick tea extracts inhibited the overall reaction of FASâ… in a mixedmanner of competitive and noncompetetive with acetyl-CoA and malonyl-CoA. Theseresults shows that inhibitor in brick tea is different from that in green tea;6. The inhibition on theβ-ketoacyl reductase of FASâ…¡(FabG) is also not weakly,the same to the ketoacyl reduction of FASâ… , their level of deactivation rate constantsrespectively is 0.116 and 0.164 (min.mg tea/ml)-1 (fast process), 5.48×10-3 (min.mgtea/ml)-1 and 6.76×10-3 (min.mg tea/ml)-1 (slow process). But The inhibition of FabG by brick tea was different from that of KR of FASâ… . which was possibly due to thedifference of their structures;7. Polarization of 3T3-L1 and fatty accumulation can be also inhibited by thebrick tea extracts. But the inhibited performance is different to the performance on FASâ… and FabG. The inhibited effects of the sample in 1985 and 2001 is not obvious on3T3-L1, the best effect is the sample in 1972 which is only 86.8ï¼…of comparison group(P＜0.05).8. After separated theaflavins and thearubigins, inhibitory function ofcomponents that included theabrownine is close to the extracts of brick tea, so it isproposed that the effective in brick tea should be theabrownine. By this tokentheabrownine is lofty polymer, but it still had strong inhibitory ability.
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