fumarates and cinnamaldehyde

The naturally occurring compound, fumaric acid, was evaluated as a potential preservative for the long-term storage of cucumbers. Fumaric acid inhibited growth of lactic acid bacteria (LAB) in an acidified cucumber juice medium model system resembling conditions that could allow preservation of cucumbers in the presence of sodium benzoate. Forty millimolars of fumaric acid were required to inhibit growth of an extremely aciduric Lactobacillus plantarum LA0445 strain at pH 3.8. Half of this concentration was required to achieve inhibition of L. plantarum LA0445 at pH 3.5. As expected growth of the spoilage yeasts Zygosaccharomyces globiformis and Z. bailii was not inhibited by fumaric acid at near saturation concentrations in the same cucumber juice medium. To usefully apply fumaric acid as a preservative in acidified foods it will be necessary to combine it with a food grade yeast inhibitor. The antimicrobial agent, cinnamaldehyde (3.8 mM) prevented growth of Z. globiformis as well as the yeasts that were present on fresh cucumbers. Acidified cucumbers were successfully preserved, as indicated by lack of yeasts or LAB growth and microbial lactic acid or ethanol production by a combination of fumaric acid and cinnamaldehyde during storage at 30 °C for 2 mo. This combination of 2 naturally occurring preservative compounds may serve as an alternative approach to the use of sodium benzoate, potassium sorbate, or sodium metabisulfite for preservation of acidified vegetables without a thermal process.. This study evaluates the potential application of alternative preservatives for the long-term storage of cucumbers in a reduced NaCl cover brine solution and without a thermal process.

Topics: Acrolein; Anti-Infective Agents; Cucumis sativus; Fermentation; Food Preservation; Food Preservatives; Fumarates; Hydrogen-Ion Concentration; Lactobacillus plantarum; Zygosaccharomyces

To investigate the mechanisms of non-immunologic contact urticaria (NICU), the effects of 1g + 1g of acetylsalicylic acid (ASA) on contact reactions to methyl nicotinate, diethyl fumarate, benzoic acid, cinnamic acid, cinnamic aldehyde and dimethyl sulfoxide were studied in 21 test subjects. Erythema and edema reactions were observed visually, and the changes in the skin blood flow were monitored using laser-Doppler flowmetry. ASA had a significant inhibitory effect on erythema from all 6 agents and also on edema from all substances except dimethyl sulfoxide. The mechanism of the effect may be a result of the inhibitory influence of ASA on prostaglandin bioformation. Thus, to avoid false negative test results, non-steroidal anti-inflammatory drugs should not be used during NICU tests.

Topics: Acrolein; Adult; Aspirin; Benzoates; Benzoic Acid; Cinnamates; Dimethyl Sulfoxide; Female; Fumarates; Humans; Irritants; Male; Nicotinic Acids; Ultrasonography; Urticaria

The decrease in the swelling capacity and the length of the refractory period after nonimmunologic contact urticaria produced by one application of six human nonimmunologic contact urticaria agents was studied with the use of the guinea pig ear test. On retesting 1 day later, all substances (benzoic acid, cinnamic acid, cinnamic aldehyde, diethyl fumarate, methyl nicotinate, and dimethyl sulfoxide) showed reactions decreased by at least 50%. This decrease was most marked with cinnamic aldehyde (91% decrease), cinnamic acid (88%), and benzoic acid (86%). The tachyphylaxis was not specific to the substance producing it; reactivity to other contact urticaria agents decreased as well. The refractory period was 4 days after methyl nicotinate, 8 days after diethyl fumarate and cinnamic aldehyde, and 16 days after the other agents. These results suggest the following practical application: there is a need for (1) appropriate scheduling in the reuse of animals for testing for nonimmunologic contact urticaria and (2) an awareness of possible false-negative results in human tests for this form of urticaria because of tachyphylaxis.

Topics: Acrolein; Animals; Benzoates; Benzoic Acid; Cinnamates; Dimethyl Sulfoxide; Ear; Female; Fumarates; Guinea Pigs; Humans; Male; Nicotinic Acids; Tachyphylaxis; Time Factors; Urticaria