Polyphenols Compositions And Antioxidant Activity Of Lycopus Lucidus Turcz

[Objective]Determined the contents of FP,SEP,SGP and ICP in Lycopus lucidus Turcz, Study and compare polyphenols compositions and antioxidant activity of Lycopus lucidus Turcz in different sampling locations and different harvest periods. Provided experimental basis and theoretical foundation for rational development and utilization of Lycopus lucidus Turcz.[Methods]1. Study the FC method in absorption wavelength and reaction time, accuracy,precision and spiked recovery. Determined the contents of FP,SEP,SGP and ICP in Lycopus lucidus Turcz with the Folin-Ciocalteu colorimetric(FC) method.2. With the high performance liquid chromatography(HPLC) method, by reference standards, Qualitative and quantitative analysis the composition of Lycopus lucidus Turcz polyphenols.3. Antioxidant activity tests: Polyphenol antioxidant activities were analyzed by the methods of DPPH and ABTS+ free radical cation scavenging activity assays, the ferric reducing ability of plasma(FRAP), the ·OH and ROO· mediated DNA damage protective effect. According to the results, linear regression, calculated IC50 values by the fitting equation. Compute iron reducing ability and ABTS+ radical scavenging, At the same time, respectively compared with the antioxidant BHT. Protective effects of DNA damage, results were analysis the semi-quantitative by the Gel imaging system,measure the effect: calculated the percentage of the double helix by the strips gray value.[Results]1. The optimal absorption wavelength of 760nm; reaction time of 40min; the coefficient variations of absorbance values and polyphenol content were 0.37% and0.38%, both less than 1.0%, so the method with high precision and good reproducibility; the average spiked recovery was 100.04%. The phenolic content had a good linear relationship(y=0.1076x+0.0197, R=0.9979).2.A high TF contents(18.94 ± 2.03 mg GAE/g DW) of Lycopus lucidus Turcz,with the harvest time move, climate temperature drop, TF contents with a increased trend overall. minimum in December and maximum in January of the next year. The content of FC was hightest(11.09 ± 1.94 mg GAE/g DW) and the content of SCP was lowest(0.85 ± 0.46 mg GAE/g DW), the contents of SEP and ICP showed no significant difference(P>0.05). The phenolic contents in S1 and S2 showed no significant difference(P>0.05). The contents of SEP and SCP showed highly significant correlation(P<0.01).3. The phenolic acids detected in the test was chlorogenic acid(87.21 ± 80.45μg/g), mainly in FP,SEP,ICP. The change of phenolic acids content was the same with that of TF.4. DPPH free radical cation scavenging activity assays of polyphenol extracts were stronger than the BHT control solution, and SCP was strongest, FP was weakest. But there were closely related between FRAP, TEAC and four phenolic contents(P<0.05). Polyphenol extracts have protective effect both in ·OH and ROO· mediated DNA damage, In 50 μmol/L concentration, samples double helix percentages were 56.69% and 70.70%, The positive control Trolox solution were71.5% and 70.5%.[Conclusions]1. With a high TF content in Lycopus lucidus Turcz, phenolic content were different in different harvest time, with the harvest time move, climate temperature drop, TF contents with a increased trend overall. The phenolic contents in S1 and S2 showed no significant difference(P>0.05). The content of FC was hightest and the content of SCP was lowest, the contents of SEP and ICP showed no significantdifference(P>0.05). The contents of SEP and SCP showed highly significant correlation(P<0.01).It showed that both may have the same metabolic pathways.2. The phenolic acids detected in the test is chlorogenic acid(87.21 ± 80.45 μg/g),mainly in FP,SEP,ICP. The other phenolic components pending further studied.3. Lycopus lucidus Turcz polyphenols have certain antioxidant capacity in DPPH,FRAP, TEAC,·OH and ROO· mediated DNA damage protective effect, suitable for develop and use as a natural antioxidant materials exploitation.