实时荧光PCR法鉴定野生食用菌中白牛肝菌成分

目的建立野生食用菌中白牛肝菌(Boletus bainiugan Dentinger)成分的荧光PCR检测方法。方法根据白牛肝菌的内源转录间隔区(internally transcribed spacer,ITS)基因序列设计白牛肝菌物种的特异性引物和探针,对样品中的靶标基因片段进行检测,并进行物种特异性检测、稳定性检测、灵敏度检测和实际应用检测。结果通过对供试的24种食用菌、动、植物材料进行检测,只有白牛肝菌出现特异性扩增,说明方法具有物种特异性;方法对白牛肝菌成分的检测灵敏度为1×10~(-4) ng/μL白牛肝菌DNA或0.1%(m/m)白牛肝菌粉。结论该方法简单、灵敏、快速、准确,能应用于野生食用菌和食品中白牛肝菌的成分检测。     

Distinguishing the Chinese materia medica Tiepishihu from similar Dendrobium species of the same genus using histological and microscopic method

The Chinese Materia Medica, Tiepishihu, used as a tonic for over one thousand years, is a well‐known precious medicine in China. According to the Chinese Pharmacopoeia, its source is the species Dendrobium officinale Kimura et Migo, which is distinguished from other species in Dendrobium genus. However, these species from the same genus are similar with Tiepishihu and caused confusion in the market. To find a quick and simple method to distinguish Tiepishihu from other similar species, histologic and microscopic methods were combined together to investigate the transverse section of stem of Tiepishihu and other similar species. Phloroglucinol test solution with hydrochloric acid was used to reveal the lignified tissue by staining the transverse section of Tiepishihu and similar species. Results revealed the unique identification characteristics to distinguish Tiepishihu from similar species, which were difficult to distinguish by other methods. The identification characteristics of Tiepishihu include the cells of vascular bundle sheath were stained red, parenchyma cells were not stained red. What's more, other species can be distinguished from each other with microscopic and histological characteristics. These characteristics proved stable and can be easily observed by normal light microscopic examination. This method is rapid, accurate, stable, and inexpensive.     

纳米传感器检测重金属离子的研究进展

近年来各类重金属离子污染受到广泛关注。传统的重金属离子监测体系主要依赖于专业的仪器设备,操作费时、设备昂贵、现场快速检测的及时性差、难以满足当前检测工作的需要。鉴于重金属离子检测分析的重要性和紧迫性,寻求简单、快捷的检测方法具有重大的现实意义。随着纳米技术的飞速发展,把纳米材料与光学、电化学、生物学及材料技术结合构建的纳米传感器促进了重金属离子检测技术的快速发展。本文对近几年来常用的几种纳米传感器在重金属检测应用中的研究进展进行了综述,包括:纳米光学传感器、纳米电化学传感器、纳米生物传感器等。本文对基于纳米传感器的检测手段进行了讨论和展望,旨在为重金属离子检测研究的发展提供参考。     

高效液相色谱法同时测定云南白花木瓜不同部位中5个成分的含量

建立了一种采用高效液相色谱(HPLC)法同时测定白花木瓜中绿原酸、芦丁、金丝桃苷、齐墩果酸、熊果酸的质量浓度的方法,比较了果皮、果肉中绿原酸、芦丁、金丝桃苷、齐墩果酸、熊果酸质量浓度的差异。结果显示,在以A相(甲醇)和B相(体积分数为16%乙腈,体积分数为0.3%磷酸水溶液)为流动相的梯度洗脱条件下,绿原酸、芦丁、金丝桃苷、齐墩果酸、熊果酸能完全分离,其中,绿原酸、芦丁、金丝桃苷在355 nm处有较好的吸收峰;齐墩果酸、熊果酸在210 nm处有较好吸收峰。绿原酸、芦丁、金丝桃苷、齐墩果酸、熊果酸质量浓度与峰面积在测定范围内均呈良好线性关系[相关系数(r)>0.999 0],平均回收率94.0%~98.4%,精密度、重复性、稳定性实验的相对标准偏差(RSD)均<2.0%。其中,绿原酸在果皮、果肉中的质量浓度分别为0.378~3.014和0.381~2.294 mg/g,差异不明显;果皮中的芦丁、金丝桃苷、齐墩果酸、熊果酸质量浓度分别为0.258~0.818、0.077~0.264、2.352~9.633和6.336~14.257 mg/g;果肉中芦丁、金丝桃苷、齐墩果酸、熊果酸质量浓度均低于定量限,与果皮中芦丁、金丝桃苷、齐墩果酸、熊果酸质量浓度相比差异显著。该法具有简易、高效、准确的特点,可用于快速定性测定白花木瓜中绿原酸、芦丁、金丝桃苷、齐墩果酸、熊果酸的组分和定量测定白花木瓜中绿原酸、芦丁、金丝桃苷、齐墩果酸、熊果酸的质量浓度。