Analysis of Nucleosides (Adenosine and Cordycepin) in the Mushroom Samples by Liquid-Chromatography and Mass Spectrometry; HPLC-MS-MS

Cordyceps, a kind of precious natural crude drugs and edible mushrooms, were used as tonic food in East Asia area and enjoyed an extensive praise for its medicinal functions. Cordycepin exhibits various bio-activities, including anticancer, antibacterial, antiviral and immune regulation activities, and it’s been a significant focus of research. However, the preparation of high‑purity cordycepin remains challenging. Also, the molecular target with which cordycepin interacts to cause an antibacterial effect remains unknown. A simple and rapid isocratic chromatographic method (HPLC), optimum separation for (adenosine and cordycepin) analytes was achieved using the mixture of water and methanol as a mobile phase (85:15, v/v). The Photo-Diode Array Detector (DAD) WR, an auto injector, and a reverse phase column, Agilent Shield RP C18/4.6 × 150 mm, 4-micron and confirmation by LC/MSMS coupled with electrospray ionization (ESI) method for simultaneous separation and determination of adenosine and cordycepin in Cordyceps sinensis (Cs) and its substitutes was developed. Selective ion monitoring (SIM) mode ([M+/H]- at m/z 136, 267 and 252) was used for quantitative analysis of above components. The linearities for the 6 substances were studied in the range between 0.001 to 0.2 mg/L and the coefficients of determination (R2) were always > 0.999. Matrix effects were also assessed by comparing the slopes obtained in solvent and matrix. The recoveries for all the substances at 3 different spike levels (0.05, 0.10 and 0.20 mg/L) were in the range 70.50-108% with RSDs < 5%. The instrumental limits of quantification were in the range 0.013-0.016 mg/L, while the reporting level of the method was 0.004 mg/L for all the aforementioned compounds. The nucleoside contents of types of natural Cs and its substitutes were determined and compared with this developed method.