Effect of 60Co-γ ray irradiation on five active ingredients in Infantile Qingfei Pills / 中草药

Objective To establish HPLC method for simultaneous determination of five active ingredients of cucurbitacin B, cucurbitacin E, praeruptorin A, praeruptorin B, and praeruptorin E in Infantile Qingfei Pills (IQP), and study the contents changes of the five effective components in IQP before and after 60Co-γ ray irradiation. Methods The Agilent-C18 column (250 mm × 4.6 mm, 5 μm) was adopted and the detection wavelength was 230 nm and 321 nm with the flow rate of 1.0 mL/min. The mobile phase consisted of A (methanol: acetonitrile) and B (0.5% glacial acetic acid solution) for gradient elution, and column temperature was 25 ℃. Irradiation does of 2, 4, 6, 8 kGy were selected to irradiate IQP respectively. The contents of five active components in IQP were compared before and after irradiation, and the significant condition was observed by t-test. Results The linear range of cucurbitacin B, cucurbitacin E, praeruptorin A, praeruptorin B, and praeruptorin E were 0.049—1.247, 0.079—1.973, 0.056—1.406, 0.028—0.705, and 0.028—0.693 μg, The average recovery were 101.2%, 99.7%, 99.9%, 98.9%, and 100.5%, and RSD were 0.6%, 0.5%, 1.2%, 1.1%, and 1.2%, respectively. After irradiation of 2, 4, 6, and 8 kGy, the effective components contents of cucurbitacin B, cucurbitacin E, praeruptorin A, praeruptorin B, and praeruptorin E were changed. After t-test in groups, the content change of cucurbitacin B was significantly after irradiation over 6 kGy (P < 0.05). Conclusion The established method has a high recovery rate, good repeatability, which is simple and practical and can be used for quality control of IQP. The changes of each component are not significant with the radiation no more than 6 kGy, which can provide a reference for the sterilization of IQP.

The inhibition of carboxylesterases by praeruptorin C, D and E / 药学学报

Praeruptorin C (PC), D (PD) and E (PE) are important compounds extracted from Peucedanum praeruptorum DUNN and have been reported to exert multiple pharmacological activities. The present study is purposed to determine the inhibition of PC, PD and PE on the activity of important phase I metabolic enzymes-carboxylesterases (CES). In vitro human liver microsomes (HLM) incubation system was used to determine the inhibition potential of PC, PD and PE on the activity of CES1 and CES2. Inhibition behaviour was determined, and in vitro-in vivo extrapolation was performed by using the combination of in vitro inhibition kinetic parameter (Ki) and in vivo exposure level of PD. PD exhibited the strongest inhibition on the activity of CES1, with 81.7% activity inhibited by 100 μmol·L-1 of PD. PD noncompetitively inhibited the activity of CES1 with the Ki to be 122.2 μmol·L-1, indicating inhibition potential of PD towards CES1 in vivo. Therefore, closely monitoring the endogenous metabolic disorders caused by PD and interaction between PD and drugs mainly undergoing CES1-catalyzed metabolism is very necessary.

Simultaneous determination of major coumarins′ content in processing Peucedani Radix materials by method of substitute for reference substance / 中国药科大学学报

@#(±)-Praeruptorin A(PA)was used as the standard reference substance to establish a new method of substitute for reference substance. The contents of both(±)-praeruptorin B(PB)and(+)-praeruptorin E(PE)were calculated by the method. The major content of coumarins in different processing materials could be gained by determining the content of(±)-praeruptorin A, which could provide scientific evidence for the research on pharmacology discrepancy and quality standards. The method was carried out on a Welch Materials Ultimate XB-C18 column(4. 6 mm×250 mm, 5 μm), with a gradient mobile phase of methanol and water at the flow rate of 1. 0 mL/min. The column temperature was 30 °C and detection wavelength was set at 322 nm. According to this method, the relative correlation factors(f)of(±)-praeruptorin B and(+)-praeruptorin E were determined as 0. 787 2 and 0. 969 0, respectively. After determine the contents of 15 batches of materials from different sources, no significant differences between substitute method and external standard method were observed. It was a feasible and credible method to determine the content of major coumarins in Peucedani Radix with different processing materials. The results showed lower contents of coumarins in processing materials than in raw materials.