RESUMO
Objective:A high performance liquid chromatography-photo-diode array（HPLC-PDA） method for the simultaneous determination of the 7 phenolic acids including danshensu，protocatechuic acid，protocatechuic aldehyde，chlorogenic acid，caffeic acid，ferulic acid and rosemary acid in Lycopus lucidus var.hirtus rhizome，analyzing and evaluating the phenolic acids in L.lucidus var.hirtus rhizome collected from different habitats，is reported here. Method:The sample was extracted by ultrasonic with 80% methanol solution，7 kinds of phenolic acids were separated on a CAPCELL PAK C18 column （4.6 mm×250 mm，5 μm） with a mobile phase consisting of methanol-0.02% formic acid aqueous （pH 3.10）by gradient elution，The detection wavelength was at 279，324 nm， the column temperature was 30 ℃ with 20 μL injection volume and the flow rate was 1.0 mL·min-1. Result:The 7 Phenolic acids had a good linear relationship （r≥0.999 9） within their respective mass concentration ranges，the average recovery was 96.49%-103.45% and the RSD was 0.5%-2.8%，the limit of determination was 0.008-0.046 mg·L-1 and the limit of quantification was 0.027-0.154 mg·L-1.The 7 kinds of phenolic acids were all detected in L.lucidus var.hirtus rhizome and the total amount was between 5 811.01 and 11 747.23 µg·g-1 ， the average amount was 7 421.05 µg·g-1.The content of 7 phenolic acids was different and the rosemary acid was the highest in all the samples with an average of 7 111.19 µg·g-1 the ratio to the total phenolic acids was 95.8%.The results of principal component analysis and cluster analysis showed that the quality of L.lucidus var.hirtus rhizome from Heze city in Shandong province was better，followed by Wanzhou district in Chongqing. Conclusion:The method was simple，sensitive，accurate，practical and reliable，and is suitable for the content determination of phenolic acid in L. lucidus var. hirtus rhizome.It is expected to provide a reference for the improvement of quality standard and a new idea for the development and utilization of L.lucidus var.hirtus rhizome.
RESUMO
OBJECTIVE:To investigate the influential factors for the stability of gardenia yellow solution. METHODS:Using pigment loss rate as index,the stability of gardenia yellow solution was investigated within 12 h under different light(strong light, natural light,dark place),temperature(4,25,60,80 ℃),pH(3.0,5.0,7.0,9.0,11.0),oxidant concentration(hydrogen per-oxide solution,0,0.1%,0.2%,0.3%) conditions. The effects of 3 natural antioxidants as tea polyphenol,rosmarinic acid and grape seed extract on the stability of gardenia yellow solution were investigated within 12 h under different light(strong light,natu-ral light,dark place) and temperature (25,60,80 ℃) conditions;the effects of different concentrations of tea polyphenol (0, 0.05%,0.1%,0.2%)on the stability of gardenia yellow solution were also investigated within 12 h. RESULTS:The pigment loss rates were 20%,10% and 10% within 12 h under 3 light conditions;5%,5%,30% and 60% under 4 temperature conditions;12%,6%,6%,6% and 16% under 5 pH conditions;4%,12%,15% and 18% under 4 oxidant concentrations. After adding 3 antioxidants,pigment loss rate decreased by 10% under different light and temperature conditions except for 80 ℃,and the de-crease of tea polyphenol was most significant;among 4 concentrations of tea polyphenol,pigment loss rate was the lowest in 0.1%group. CONCLUSIONS:Gardenia yellow solution can't keep stable under strong light and high temperature;3 antioxidants can im-prove the stability of gardenia yellow solution,especially 0.1%tea polyphenol.