摘要
Aim: To compare the contents of nucleosides from natural Cordyceps sinensis and cultured Cordyceps mycelia, and to study the effect of humidity and heat on the content of nucleosides. Methods: The contents of nucleosides were determined by using high performance capillary electrophoresis (HPCE). Beckman P/ACE System 5010 apparatus equipped with a UV detector and a Beckman untreated fused-silica capillary (57 cm 75 mm, 50 cm effective length) was used. Before sample injection, the capillary was rinsed with 1 molL-1 sodium hydroxide solution and running buffer for 5 min, respectively. A voltage of 20 kV was applied for the separation. Pressure injection was 586 kPa for 6 seconds, and the wavelength of detector was 254 nm. The running time was 20 min at 20 oC. The effect of humidity and heat on the contents of nucleosides from natural Cordyceps sinensis and cultured Cordyceps mycelia was observed for 1, 3, 5 and 10 days at temperature 40 oC, and relative humidity 75%. Results: The content of nucleosides from natural Cordyceps sinensis was higher than that from cultured Cordyceps mycelia. But the contents of nucleosides from freshly collected natural Cordyceps sinensis were very low, even below the limit of quantitation. The contents of nucleosides from natural Cordyceps sinensis were significantly increased by humidity and heat, but this phenomenon was not observed in cultured Cordyceps mycelia. Conclusion: There are differences between the nucleosides from natural Cordyceps sinensis and cultured Cordyceps mycelia. The nucleosides in natural Cordyceps sinensis may be derived from the degradation of nucleic acids. This implies that adenosine being used for the quality control of natural Cordyceps sinensis may have to be reconsidered.
目的 比较天然和人工冬虫夏草中核苷类成分的含量,并对其变化进行考察。方法 采用高效毛细管电泳法测定天然和人工冬虫夏草中核苷类成分的含量;考察湿热对冬虫夏草中核苷类成分含量的影响。结果 人工冬虫夏草的核苷含量明显高于天然冬虫夏草;新采集的天然冬虫夏草中核苷类物质含量极低,而采集日久者核苷类成分含量却较高;湿热可明显增加天然冬虫夏草中核苷类物质的含量,但对人工冬虫夏草中核苷类成分的含量无明显影响。结论 天然和人工冬虫夏草中核苷类成分存在一定差异,天然冬虫夏草中核苷类物质可能主要来源于大分子核苷(酸)的降解,腺苷在天然冬虫夏草质量控制中的应用价值尚值得进一步研究。
