Toxicity of reactive carbonyl compounds to plants

In plants, environmental stresses result in oxidative stress, lipid peroxidation and the generation of reactive carbonyl aldehydes. Reactive carbonyl aldehydes are downstream products of reactive oxygen species which can be described as critical cell-damaging agents in plants under various environmental stresses. In this paper toxicity of reactive carbonyl aldehydes and its generation under stress conditions are discussed. Moreover, involvement of reactive carbonyl aldehydes in stress- induced damage to plants is demonstrated. Toxic effect of reactive aldehydes such as acrolein, malondialdehyde and crotonaldehyde in plants under different stresses and their high electrophilicity is also discussed. Increases in malondialdehyde was demonstrated in UV-C stressed plants as the result of carbonyl modified proteins. A malondialdehyde is one of the widely shown aldehyde, which can be demonstrated as an indicator of reactive oxygen species. Malondialdehyde isomerized to 3-hydroxyacrolein whereas it can be described as a dialdehyde. The article considers detrimental actions of reactive carbonyl aldehydes and their chemical properties as well as detoxification of reactive carbonyl aldehydes by multiple enzymes such as aldehyde dehydrogenase, aldehyde reductase, aldo-keto reductase and 2-alkenal reductase.

Derivatization of Methylglyoxal for LC-ESI-MS Analysis—Stability and Relative Sensitivity of Different Derivatives

The great research interest in the quantification of reactive carbonyl compounds (RCCs), such as methylglyoxal (MGO) in biological and environmental samples, is reflected by the fact that several publications have described specific strategies to perform this task. Thus, many reagents have also been reported for the derivatization of RCCs to effectively detect and quantify the resulting compounds using sensitive techniques such as liquid chromatography coupled with mass spectrometry (LC-MS). However, the choice of the derivatization protocol is not always clear, and a comparative evaluation is not feasible because detection limits from separate reports and determined with different instruments are hardly comparable. Consequently, for a systematic comparison, we tested 21 agents in one experimental setup for derivatization of RCCs prior to LC-MS analysis. This consisted of seven commonly employed reagents and 14 similar reagents, three of which were designed and synthesized by us. All reagents were probed for analytical responsiveness of the derivatives and stability of the reaction mixtures. The results showed that derivatives of 4-methoxyphenylenediamine and 3-methoxyphenylhydrazine—reported here for the first time for derivatization of RCCs—provided a particularly high responsiveness with ESI-MS detection. We applied the protocol to investigate MGO contamination of laboratory water and show successful quantification in a lipoxidation experiment. In summary, our results provide valuable information for scientists in establishing accurate analysis of RCCs.