浅析活性低聚糖食品的开发

活性低聚糖不能被人体消化道内酶系酶解,而直接进入大肠内为双歧杆菌所利用,是肠道有益茵群的有效增殖因子。活性低聚糖因其独特的生理功能,在国外已成为一类重要的保健食品基料。本文就活性低聚糖食品的营养保健作用和开发利用进行了初步阐述。     

人与自然公正的双重伦理底蕴——以动物权利理论为视角

随着生态危机的日益加重,近现代许多伦理学家都试图从各个角度去阐述自然存在物具有着本身的内在价值,并在此基础上进一步认为人类应当承认自然的权利,进而建立起人与自然之间良好的公正形态。在环境危机日益加重的今天,批判继承这些思想家的理论思想对于树立起合理的生态意识具有着积极的意义。从动物存在具有权利的理论出发,去承认并尊重自然存在物的内在权利,不仅仅是人类自身延续的必然要求,具有着强烈的现实效用性;而且更体现着人类认知理性与道德理性的发展,具有着道德崇高性．     

Comprehensive chemical profiling and quantification of Shexiang Xintongning tablets by integrating liquid chromatography-mass spectrometry and gas chromatography-mass spectrometry

Shexiang Xintongning tablet (SXXTN) is a traditional Chinese medicine (TCM) preparation for the treatment of coronary heart disease (CHD) angina pectoris. However, due to the complexity of the compounds in SXXTN, the active chemical components responsible for the therapeutic effect are still ambiguous. The purpose of our study was to characterize the chemical profile of SXXTN and quantify the representative chemicals. The high-performance liquid chromatography coupled with time-of-flight mass spectrometry (HPLC-QTOF MS) method and gas chromatograph coupled with mass spectrometry (GC–MS) method were utilized to identify the chemical constituents of SXXTN. A total of 140 compounds including alkaloids, ginsenosides, organic acids, esters, triterpenes, phthalides and amino acid were identified in accordance with their retention times, accurate masses and characteristic MS/MS fragment patterns. Forty-four volatile components were characterized by GC–MS through NIST database matching. In the further research of quantitative analysis, 40 non-volatile compounds and 17 volatile compounds were determined and successfully applied for detecting in 7 batches of SXXTN samples by high performance liquid chromatography coupled with triple-quadrupole tandem mass spectrometry (HPLC-QQQ MS) and gas chromatograph coupled with triple-quadrupole tandem mass spectrometry (GC-QQQ MS) in multiple reaction monitoring (MRM) mode, respectively. The quantitative methods were verified in linearity, precision, repeatability stability and recovery. The above results indicated that the established method was practical and reliable for synthetical quality evaluation of SXXTN. In addition, our study might supplement the chemical evidence for disclosing the material basis of its therapeutic effects.     

Burning Graphite Faster than Carbon Black: A Case of Diffusion Control

External diffusion may be exploited as a tool to purify materials in a way thought to be inaccessible from a chemical reactivity point of view. A mixture of two carbonaceous materials, graphite and carbon black, are thermally oxidized in either i) outside total diffusion-limited regime or ii) total diffusion-limited regime. Depending on the treatment applied it is possible to purify either graphite, a trivial task, or carbon black, a task thought impossible. Introducing geometrical selectivity, controlled total diffusion-limited chemistry exceeds by far the field of carbon materials and can be used as an engineering tool for many materials purification, original synthesis, or to introduce asymmetry in a system. Several examples for direct applications of the findings are mentioned.     

Nanoparticle-Decorated Biomimetic Extracellular Matrix for Cell Nanoencapsulation and Regulation

Cell encapsulation has been studied for various applications ranging from cell transplantation to biological production. However, current encapsulation technologies focus on cell protection rather than cell regulation that is essential to most if not all cell-based applications. Here we report a method for cell nanoencapsulation and regulation using an ultrathin biomimetic extracellular matrix as a cell nanocapsule to carry nanoparticles (CN²). This method allows high-capacity nanoparticle retention at the vicinity of cell surfaces. The encapsulated cells maintain high viability and normal metabolism. When gold nanoparticles (AuNPs) are used as a model to decorate the nanocapsule, light irradiation transiently increases the temperature, leading to the activation of the heat shock protein 70 (HSP70) promoter and the regulation of reporter gene expression. As the biomimetic nanocapsule can be decorated with any or multiple NPs, CN² is a promising platform for advancing cell-based applications.