Evolution of the Aroma Volatiles of Pear Fruits Supplemented with Fatty Acid Metabolic Precursors

Abstract

Abstract:To examine the biochemical metabolism of aroma volatiles derived from fatty acids, pear fruits were incubated in vitro with metabolic precursors of these compounds. Aroma volatiles, especially esters, were significantly increased, both qualitatively and quantitatively, in pear fruits fed on fatty acid metabolic precursors. Cultivars having different flavor characteristics had distinctly different aroma volatile metabolisms. More esters were formed in fruity-flavored "Nanguoli" fruits than in green-flavored "Dangshansuli" fruits fed on the same quantities of linoleic acid and linolenic acid. Hexanal and hexanol were more efficient metabolic intermediates for volatile synthesis than linoleic acid and linolenic acid. Hexyl esters were the predominant esters produced by pear fruits fed on hexanol, and their contents in "Dangshansuli" fruits were higher than in "Nanguoli" fruits. Hexyl esters and hexanoate esters were the primary esters produced in pear fruits fed on hexanal, however the content of hexyl ester in "Dangshansuli" was approximately three times that in "Nanguoli". The higher contents of hexyl esters in "Dangshansuli" may have resulted from a higher level OPEN ACCESSMolecules 2014, 19 20184 of hexanol derived from hexanal. In conclusion, the synthesis of aroma volatiles was largely dependent on the metabolic precursors presented.

Transcriptome profiling reveals the candidate genes associated with aroma metabolites and emission of pear (Pyrus ussuriensis cv.)

“…The quantity of volatile aroma (Qin et al, 2014) was largely dependent on the quantity of precursors (linoleic and linolenic acids) present. Lee et al (2012) reported that -6 and -3 fatty acid desaturase (FAD) played a key role in the synthesis of the unsaturated fatty acids linoleic (18:2) and linolenic (18:3) acids.…”

Dietary fatty acids promote sleep through a taste‐independent mechanism

“…For example, they are present in the banana during the later stages of ripening . In fruit, fatty acids are metabolized to form esters, that are among the most behaviorally relevant compounds, as both the larval and adult olfactory systems are largely tuned to this class of volatiles . Although the sensory detection of these compounds have been studied in detail, their role in the modulation of many behaviors remain poorly understood.…”

Dietary fatty acids promote sleep through a taste-independent mechanism

“…For example, they are present in the banana during the later stages of ripening (Zhu et al, 2018). In fruit, fatty acids are metabolized to form esters (Balbontín et al, 2010; Qin et al, 2014), which are among the most behaviorally relevant compounds, as both the larval and adult olfactory systems are largely tuned to this class of volatiles (Grabe et al, 2018). Although much is known about the peripheral detection of these chemicals, it remains unknown how their consumption modulates behavior.…”