Studies on the Food Additive Propyl Gallate: Synthesis, Structural Characterization, and Evaluation of the Antioxidant Activity

• Type: Article in International Scientific Journal
• Date: 2012

Authors

garrido, jorge (Author) Other; manuela garrido, e. (Author) Other; borges, fernanda (Author) FCUP

Journal

Title: Journal of Chemical Education

Vol. 89

Pages: 130-133

ISSN: 0021-9584

Publisher: American Chemical Society

Indexing

ISI Web of Knowledge - 32 Citations

Scopus - 34 Citations

Other information

Authenticus ID: P-002-GZN

DOI: 10.1021/ed900025s

Abstract (EN): Antioxidants are additives largely used in industry for delaying, retarding, or preventing the development of oxidative deterioration. Propyl gallate (E310) is a phenolic antioxidant extensively used in the food, cosmetics, and pharmaceutical industries. A series of lab experiments have been developed to teach students about the importance and significance of antioxidants in industry. In the first laboratory, the antioxidant propyl gallate is obtained and the structure identified. Students become acquainted with laboratory techniques such as extraction, crystallization, and thin-layer chromatography. In the second laboratory, spectroscopic data (IR, H-1 and C-13 NMR) is acquired and interpreted. Students become familiar with the basic concepts of organic compound identification. In the third laboratory, the antioxidant activity of the synthesized additive and gallic acid is evaluated by DPPH (2,2-diphenyl-1-picrythydrazyl) assay using trolox (6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid) as standard. Concepts such as free radical chemistry, preparation of analytical samples, calibration methods, and UV-vis spectrophotometry, are reviewed. This series of experiments can also be used to explore the effect of substituents on radical stability because structurally related compounds were found to have qualitatively different antioxidant profiles.

Language: English

Type (Professor's evaluation): Scientific