Benzaldehyde (BAld) is one of the most widely distributed volatiles that contributes to flavor and defense in plants. Plants regulate BAld levels through various pathways, including biosynthesis from trans-cinnamic acid (free BAld), release from hydrolysis of glycoside precursors (BAld-H) via multiple enzymatic action steps, and conversion into downstream chemicals. Here, we show that BAld-H content in peach (Prunus persica) fruit is up to 100-fold higher than that of free BAld.
View Article and Find Full Text PDFCuticular wax has been implicated in the first line of plant defense mechanism against external stresses. In this study, cuticular wax on the fruits of two rabbiteye blueberry cultivars cv. Baldwin and Brightwell were examined in terms of the morphology and chemical composition during fruit development in the presence and absence of pre-harvest melatonin (MT) treatment.
View Article and Find Full Text PDFBackground: Pomelo is one of the three major species of citrus. The fruit accumulates a variety of abundant secondary metabolites that affect the flavor. UDP-glycosyltransferases (UGTs) are involved in the glycosylation of secondary metabolites.
View Article and Find Full Text PDFApple is rich in flavonol glycosides, which are believed to contribute to putative health benefits associated with apple consumption. Glycosylation, catalyzed by uridine diphospho-glycosyltransferases (UGTs), is the last step in flavonol biosynthesis, which confers molecular stability and solubility to the flavonol. In the present study, the involvement of two UGTs, MdUGT75B1 and MdUGT71B1, in flavonol biosynthesis in apple was investigated.
View Article and Find Full Text PDFThe monoterpene linalool is a major contributor to aroma and flavor in peach (Prunus persica) fruit. It accumulates during fruit ripening, where up to ~40% of the compound is present in a non-volatile glycosylated form, which affects flavor quality and consumer perception by retronasal perception during tasting. Despite the importance of this sequestration to flavor, the UDP-glycosyltransferase (UGT) responsible for linalool glycosylation has not been identified in peach.
View Article and Find Full Text PDFComposition and changes in free volatiles have been extensively studied in citrus fruit such as mandarin. However, components of glycosidically bound volatiles and changes during fruit ripening have been rarely investigated. A total of 56 glycosidically-bound volatiles were identified in fruit peel at four ripening stages.
View Article and Find Full Text PDFPlants generate protective molecules in response to ultraviolet (UV) light. In laboratory experiments, 48 h UV-B irradiation of peach fruits and leaves reduced the flavour-related monoterpene linalool by 60%. No isoprene was detected, but other terpenoids increased significantly, including a threefold accumulation of the sesquiterpene (E,E)-α-farnesene, which was also increased by jasmonic acid treatment.
View Article and Find Full Text PDFPeach ( L. Batsch) is a commercial grown fruit trees, important because of its essential nutrients and flavor promoting secondary metabolites. The glycosylation processes mediated by UDP-glycosyltransferases (UGTs) play an important role in regulating secondary metabolites availability.
View Article and Find Full Text PDFJ Opt Soc Am A Opt Image Sci Vis
November 2009
In this paper we extend the fast-all-modes method and the numerical modified steepest-descent-path method to the optical frequency range by finding all modes and solving the total electric field in three dimensions that is due to a point source above a lossy thin metal film with a negative permittivity situated between two dissimilar dielectric materials. We show that up to four proper surface wave modes may propagate on the film surface, including both backward and forward waves. We also solve for the electric field below the lossy thin metal film and verify the existence of superlensing of the electric field, comparing that case to the case of a dielectric film where no superlensing occurs.
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