Determination of mycotoxins in pu-erh tea, black tea, and green tea samples / 中国中药杂志

To establish a robust method for the determination of mycotoxins in tea samples, and to provide means for the quality and safety control of tea products. Samples of 20 tea products acquired from international market were extracted by organic solvents (acetonitrile containing 0.1% formic acid) or hot water, respectively. The extracts were analyzed by UPLC-MS/MS.A good linear regression was achieved in a range of 39.1 to 5 000 ng•L⁻¹ for aflatoxin B1 (AFB1) and aflatoxin G1 (AFG1), 117 to 15 000 ng•L⁻¹ for aflatoxin B2 (AFB2) and aflatoxin G2 (AFG2), 2.44 to 313 ng•L⁻¹ for fumonisin B1 (FB1), fumonisinB2 (FB2) and fumonisin B3 (FB3), and 3 125 to 5 000 ng•L⁻¹ for deoxynivalenol, with recovery rates between 85.7% and 99.6%. The coefficient of the linear equation for all standards was greater than 0.999 0, and the RSD value was less than 10%. Mycotoxins were detected in several tea samples using the two extraction methods but with different outcomes. The levels of mycotoxins detected ranging from 0.15 to 7.31 μg•kg⁻¹ were well below the State or US FDA regulation limits of mycotoxins in food products. Both methods are simple, accurate, and sensitive, and thus, suitable for the quantitative determination of mycotoxins in different food products. The method with the 80 ℃ hot-water extraction is more appropriate to determine the trace amounts of mycotoxins in tea leaves that are likely to be present in brewed tea liquor, while organic solvent method is more suitable for the detection of mycotoxins in ingestible foods.

Analysis of matrine and oxymatrine in Kushensu injection by UPLC/Q-TOF-MS / 中国中药杂志

<p><b>OBJECTIVE</b>To develop a method for the determination of matrine and oxymatrine in Kushensu injection by ultra performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC/Q-TOF-MS).</p><p><b>METHOD</b>The analysis was performed on a Acquity UPLC BEH C18 column (2.1 mm x 100 mm, 1.7 microm) with the gradient elution of 10 mmol x L(-1) amine acetate (pH 8, adjusted by aqueous ammonia) and methanol. The flow rate was set as 0.30 mL x min(-1). The column temperature was maintained at 30 degrees C. The peaks were detected at 210 nm and the injection volume was 2 microL.</p><p><b>RESULT</b>The calibration curves showed good linearity within the test ranges of 0.084-3.36 microg for matrine and 0.086-3.44 microg for oxymatrine, respectively. The mean recoveries were 103.2%, 98.7%, and the RSD were 1.5%, 1.2%, respectively.</p><p><b>CONCLUSION</b>The established method is simple, rapid and sensitive, can be used for the quality control of matrine and oxymatrine in Kushensu injection through the manufacturing process and clinical implement.</p>

Application of metabolomics in research of plant metabolites / 中国中药杂志

Metabolomics, a branch of systems biology, has gained extensive attention and profound achievements in the plant. Although plant metabolomics is to be explored, it has been one of the most effective methods to study the physiological and biochemical process and gene modification in pattern plants. We herein summarized the concept, development, and application of metabolomics and prospected the potentials in the metabolite profiling for plant. Metabolomics provides an omics' methodology to elucidate the whole biological process, identify and quantify the complex components in the plant. A number of metabolites present in the plant are active components of traditional Chinese medicine, and these bioactive components are influenced by the multi-factors such as environment, species, and processing methods etc. Therefore, it is of great importance to analyze a wide spectrum of compositions with diverse chemical characteristics and varied concentration, which is the foundation to quality control, allowing the elucidation of the pharmacological effectiveness, and further exploiting of traditional Chinese medicine.