2-hexenal--z-isomer and pentanal

Small white apricot is well known as a famous fresh fruit and even a folk medicine in Xinjiang. To investigate nutritive value, antioxidant activity, and flavor of small white apricot, sugars, organic acids, total flavonoids, phenolic compounds, antioxidant activities, and volatile compounds in five apricot cultivars were examined by high-performance liquid chromatography (HPLC) and headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry (HS-SPME-GC-MS). The results showed that sucrose (32.94% to 42.49%), malic acid (69.21% to 76.75%), and quercetin-3-rutinoside (72.84% to 74.05%) were the dominant sugar, organic acid, and phenolic compounds in small white apricot, respectively. The antioxidant activity reached up to 61.72 to 135.52 mg TEs 100 g

Topics: Aldehydes; Antioxidants; Carboxylic Acids; China; Flavonoids; Fruit; Gas Chromatography-Mass Spectrometry; Odorants; Phenols; Prunus armeniaca; Solid Phase Microextraction; Sugars; Taste; Volatile Organic Compounds

Induction of pumpkin (Cucurbita maxima Duch.) glutathione S-transferase (GST, EC 2.5.1.18) by aldehydes and related compounds was examined. All of the tested compounds induced pumpkin GST to different degrees, and it was found that (1) aldehydes induce GST directly and alcohols induce GST indirectly, and (2) alpha,beta-unsaturated aldehydes are the most effective inducers and their potency is related to the Michael acceptors reaction. The results of Western blot analysis showed that the patterns of induction of CmGSTU1, CmGSTU2 and CmGSTU3 were similar to the patterns of activity with the exception of alpha,beta-unsaturated carbonyl compounds. Among the three compounds, crotonaldehyde caused the highest activity induction (9.2-fold), but Western blot expression was the highest only for CmGSTU3. CmGSTF1 was almost non-responsive to all of the tested stresses. Results of induction studies suggested that efficient pumpkin GST inducers have distinctive chemical features. The in vitro activity of the enzyme was inhibited by ethacryanic acid, trans-2-hexenal, crotonaldehyde, and pentanal. Ethacryanic acid was found to be the most potent inhibitor with an apparent I(50) value of 6.90+/-2.06 micro M, while others were weak to moderate inhibitors. The results presented here indicate that plant GSTs might be involved in the detoxification of physiologically and environmentally hazardous aldehydes/alcohols.

Topics: Alcohols; Aldehydes; Blotting, Western; Cucurbita; Enzyme Induction; Ethacrynic Acid; Gene Expression Regulation, Enzymologic; Gene Expression Regulation, Plant; Glutathione Transferase