Study On Serotonin Derivatives From Safflower Oil Cake

Serotonin derivatives which attributes to indole compounds is a kind of the minor constituents in safflower oil cake with significant biological function. It was found that serotonin derivatives has many physiological functions such as anti-oxidation, scavenging free radical, anti-cancer, against postischemic myocardial dysfunction, and improving the immunity.The objective of this research was to extract ,quantify, identify serotonin derivatives from safflower oil cake. The antioxidant activity of serotonin derivatives was also studied here.Firstly, a spectrophotometric method for the determination of total serotonin derivatives is described in this paper. The final determination of serotonin derivatives is based upon a color reaction between serotonin creatinine sulfate and Ehrlich's reagent. The average recoveries and coefficient variation were 99.6 % and 1.19 %.Secondly, the influences of several factors for extraction were studied. The extraction effects of total serotonin derivatives in safflower oil cake with different solvent were studied. The results indicated that anhydrous ethyl alcohol was the optimum solvent. Mono-factor experiments and orthogonal experiments showed that the optimum extraction conditions were as follows: proportioning the solvent to the safflower oil cake(20 mesh) as 3.5:1, extracting with anhydrous ethyl alcohol at 85℃, holding for 180 minutes and extracting four times. The ratio of the solvent to the safflower oil cake could have a greater impact on extraction of the total serotonin derivatives. With the above method, the content of serotonin derivatives is about 2.6mmol/g under the optimum extraction conditions.Thirdly, With the use of TLC,HPLC-MS and HPLC-UV methods, serotonin derivatives was found to compose of N-feruloylserotronin(37.27%), N-(p-coumaroyl)serotonin(36.95%), N-(p-coumaroyl)serotonin-mono-β-D- glucopyranoside(3.93%), N-feruloylserotronin) -mono-β-D-glucopyranoside(0.98%), 4,4"-bis(N-p-coumaroyl)serotonin(1.53%), 4-N-(p-coumaroyl) serotonin -4"-yl]-N- feruloylserotonin(1.80%) and 4,4"-bis(N-feruloyl)serotonin (2.23%). With the use of TLC and HPLC methods, two new serotonin derivatives which respectively are isomeric compounds of N-feruloylserotronin and N-(p-coumaroyl)serotonin were firstly found from safflower oil cake.Finally, the free radical scavenging capacity of serotonin derivatives was investingated. The results showed serotonin derivatives could distinctly scavenge the free radical (DPPH·) and could scavenge the free radical(O2-?and?OH).