目的建立快速测定药材外源性有害成分赭曲霉毒素(OTA)的含量,为药材快速质控技术提供前期基础。方法制定一段一端标记有羧基荧光素(FAM)荧光团的赭曲霉毒素DNA适配体序列片段:5'-GAT-CGGTGTGGGTGGCGTAAAGGGAGCATCGGACA-FAM-3',...目的建立快速测定药材外源性有害成分赭曲霉毒素(OTA)的含量,为药材快速质控技术提供前期基础。方法制定一段一端标记有羧基荧光素(FAM)荧光团的赭曲霉毒素DNA适配体序列片段:5'-GAT-CGGTGTGGGTGGCGTAAAGGGAGCATCGGACA-FAM-3',在20 mM Tris-HCl缓冲液(包含100 mM NaCl、5.0mM KCl、5.0 mM MgCl_2,pH 7.4)中,以氮化碳纳米片(g-C_3N_4nanosheets,CNNS)为荧光淬灭基质,利用CNNS对游离态DNA和OTA-DNA复合态的吸附差异和其对FAM的荧光淬灭作用,实现对OTA的检测。结果该传感器对OTA的检测线性范围为1~100 nM,检测限为0.7 nM,且10倍浓度的赭曲霉毒素B和黄曲霉毒素B1均不会对检测结果有明显影响。结论氮化碳纳米片耦合OTA适配体的荧光检测方法具有较高的选择性和灵敏度,且操作简单,有望成为中药材中赭曲霉毒素含量测定的新方法。展开更多
In order to reveal transpiration rates of wetland plants and its relationships to micro-meterological factors in a mountain valley wetland, relative humidity, air temperature, leaf temperature, soil temperature, photo...In order to reveal transpiration rates of wetland plants and its relationships to micro-meterological factors in a mountain valley wetland, relative humidity, air temperature, leaf temperature, soil temperature, photo flux density and transpiration rates were measured once two hours in a Carex meyeriana wetland of the Changbai Mountain valley in dry (July) and wet (September) of 2003, respectively. Results showed that the tendency of "decreasing after increasing" was obvious in wet season. However, a relatively stable trend was observed for the transpiration in dry season.. Generally, the photon flux density of Carex meyeriana was higher in wet season than that in dry season. However, the variabilities of leaf temperature, air temperature and relative humidity were similar in both seasons. Higher transpiration rates of Carex meyeriana leaves were observed in July (varied from 40 to 150 mol·m-2·s-1) compared to those (varied from 7 to 14 mol·m-2·s-1) in September. Transpiration rates were significantly correlated with air temperature (P<0.01), leaf temperature (P<0.01), and wind speed (P<0.05), but correlationship between relative humidity and photo flux density was not significant (P<0.05).展开更多
文摘目的建立快速测定药材外源性有害成分赭曲霉毒素(OTA)的含量,为药材快速质控技术提供前期基础。方法制定一段一端标记有羧基荧光素(FAM)荧光团的赭曲霉毒素DNA适配体序列片段:5'-GAT-CGGTGTGGGTGGCGTAAAGGGAGCATCGGACA-FAM-3',在20 mM Tris-HCl缓冲液(包含100 mM NaCl、5.0mM KCl、5.0 mM MgCl_2,pH 7.4)中,以氮化碳纳米片(g-C_3N_4nanosheets,CNNS)为荧光淬灭基质,利用CNNS对游离态DNA和OTA-DNA复合态的吸附差异和其对FAM的荧光淬灭作用,实现对OTA的检测。结果该传感器对OTA的检测线性范围为1~100 nM,检测限为0.7 nM,且10倍浓度的赭曲霉毒素B和黄曲霉毒素B1均不会对检测结果有明显影响。结论氮化碳纳米片耦合OTA适配体的荧光检测方法具有较高的选择性和灵敏度,且操作简单,有望成为中药材中赭曲霉毒素含量测定的新方法。
基金supported by the National Basic Research Program of China (No.2006CB403301)the National Natural Science Foundation Project (4)the Emphasis Project Fund of National Eleventh Five-Year Scientific and Technical Support Plans (No.2006BAB04A08)
文摘In order to reveal transpiration rates of wetland plants and its relationships to micro-meterological factors in a mountain valley wetland, relative humidity, air temperature, leaf temperature, soil temperature, photo flux density and transpiration rates were measured once two hours in a Carex meyeriana wetland of the Changbai Mountain valley in dry (July) and wet (September) of 2003, respectively. Results showed that the tendency of "decreasing after increasing" was obvious in wet season. However, a relatively stable trend was observed for the transpiration in dry season.. Generally, the photon flux density of Carex meyeriana was higher in wet season than that in dry season. However, the variabilities of leaf temperature, air temperature and relative humidity were similar in both seasons. Higher transpiration rates of Carex meyeriana leaves were observed in July (varied from 40 to 150 mol·m-2·s-1) compared to those (varied from 7 to 14 mol·m-2·s-1) in September. Transpiration rates were significantly correlated with air temperature (P<0.01), leaf temperature (P<0.01), and wind speed (P<0.05), but correlationship between relative humidity and photo flux density was not significant (P<0.05).