Development and evolution of natural antioxidant active packaging / Desarrollo y evolución de los empaques activos antioxidantes naturales

Since 1930s, production of synthetic plastics from non-renewable resources (mainly from petroleum) has been growing with applications in different fields. The use of plastics in packaging began after World War II. Polyethylene films introduced transparent and resealable bags, being the bread bags the first application of contact with food. Nowadays, packaging is the largest single market for plastics (about a quarter of the total production) with a high proportion used for direct contact with foods (1). Polymers and low molecular weight additives compose the plastics, where the latter are necessary to maintain the plastic properties (2). During the late-1970s and early-1980s there was a number of publications reporting that small molecules diffused through the polymer chains in the plastic and moved to the contained food by means of a process called migration (3, 4). This kind of interaction between plastic packaging and food opened a new research field, and many materials were analysed for migration. Also, the identity and quantification of the diffusion rate of the migrants were reported, and legislation was established in order to protect the health of consumers who were not aware about the plastic components contaminating their food (5). The beginning of the 21 Century brought new analytical technologies that helped to quantify migration levels that were not able to be detected with the 20 Century technologies. The researchers working in that field concluded at some point that the interaction between plastic and food exist in all the cases, and could be limited but not completely avoided.

Metabonomics analytical technologies and metabolite identification / 国际药学研究杂志

In recent years, the metabonomics technologies have been widely used in numerous science fields. The rapid, accurate analysis and identification for a large number of small molecular metabolites is the key of metabonomics studies, which relies largely on the progress in relevant technologies. The development and combination of many technologies, such as nuclear magnetic resonance (NMR), mass spectrometry (MS), chromatography and capillary electrophoresis, make them possible for the wide application of metabonomics. NMR and MS are the most important technical platforms in metabonomics studies. The unambiguous identification of metabolites is the basic task of metabonomics studies. The research progress in metabonomics analytical technologies and metabolite identification is reviewed in this paper.