2-(1H-pyrrolyl)carboxylic acids as pigment precursors in garlic greening
| Autor: | Husile Nanding, Fang Chen, Dan Wang, Na Han, Guanghua Zhao |
|---|---|
| Rok vydání: | 2008 |
| Předmět: |
Chemical Phenomena
Food Handling Carboxylic acid Carboxylic Acids Pigment chemistry.chemical_compound Greening Pyruvic Acid Moiety Organic chemistry Garlic Incubation Thiosulfinate Pyrrole chemistry.chemical_classification Chemistry Chemistry Physical food and beverages General Chemistry Pigments Biological Sulfinic Acids visual_art Sulfoxides visual_art.visual_art_medium Pyruvic acid General Agricultural and Biological Sciences |
| Zdroj: | Journal of agricultural and food chemistry. 56(4) |
| ISSN: | 0021-8561 |
| Popis: | Six model compounds having a 2-(1 H-pyrrolyl)carboxylic acid moiety and a hydrophobic R group were synthesized to study their effects on garlic greening, the structures of which are similar to that of 2-(3,4-dimethyl-1 H-pyrrolyl)-3-methylbutanoic acid (PP-Val) (a possible pigment precursor for garlic greening). The puree of freshly harvested garlic bulbs turned green after being soaked in solutions of all these compounds, and with both increasing concentrations and incubation time the green color of the puree became deeper. In contrast, neither pyrrole alone nor pyrrole combined with free amino acids had the ability to discolor the puree. The compounds exhibited a good relationship between structure and activity of garlic greening, namely, the smaller the size of the R group, the larger the contribution. Also, it was found that the unidentified yellow species can be produced by reacting the model compounds with pyruvic acid at room temperature (23-25 degrees C). Moreover, blue species were formed by incubation of the model compounds with di(2-propenyl) thiosulfinate at room temperature. On the basis of these observations, a pathway for garlic greening was proposed. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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