Comprehensive study of volatile compounds and transcriptome data providing genes for grape aroma

Abstract

Background Fruit aroma is an important quality with respect to consumer preference, but the most important aroma compounds and their genetic regulatory mechanisms remain elusive. Results In this study, we qualitatively analysed volatile compounds in the pulp and skin of five table grape cultivars with three aroma types (muscat, strawberry, and neutral) using solid-phase microextraction gas chromatography/mass spectrometry. We identified 215 aroma compounds, including 88 esters, 64 terpenes, and 29 alcohols, and found significant differences in the number of compounds between the pulp and skin, especially for terpenes. Skin transcriptome data for the five grape cultivars were generated and subjected to aroma compound-gene correlation analysis. The combined transcriptomic analysis and terpene profiling data revealed 20 candidate genes, which were assessed in terms of their involvement in aroma biosynthetic regulation, including 1 VvCYP (VIT_08s0007g07730), 2 VvCCR (VIT_13s0067g00620, VIT_13s0047g00940), 3 VvADH (VIT_00s0615g00010, VIT_00s0615g00030, VIT_ 00s0615g00020), and 1 VvSDR (VIT_08s0040g01200) in the phenylpropanoids synthesis pathway, and 1 VvDXS (VIT_05s0020g02130) and 6 VvTPS (VIT_13s0067g00370, Vitis_vinifera_newGene_3216, VIT_13s0067g00380, VIT_13s0084g00010, VIT_00s0271g00010, and VIT_13s0067g00050) in the methylerythritol phosphate pathway (involved in the production and accumulation of aromatic compounds). Additionally, 2 VvMYB (VIT_17s0000g07950, VIT_03s0063g02620) and 1 VvGATA (VIT_15s0024g00980) transcription factor played important regulatory roles in the accumulation of key biosynthetic precursors of these compounds in grapes. Our results indicated that downstream genes, specifically 1 VvBGLU (VIT_03s0063g02490) and 2 VvUGT (VIT_17s0000g07070, VIT_17s0000g07060) are involved in regulating the formation and volatilization of bound compounds in grapes. Conclusions The results of this study shed light on the volatile compounds and “anchor points” of synthetic pathways in the pulp and skin of muscat and strawberry grapes, and provide new insight into the regulation of different aromas in grapes.

Breeding new seedless table grapevines for a more sustainable viticulture in Mediterranean climate

“…As far as the berry flavor trait is concerned, half of the crosses between neutral female and muscadine male resulted in 49% of neutral offspring, 18% in aromatic offspring, and 34% in partly aromatic and partly neutral progeny. In grapevine, monoterpenes are the key compounds responsible for the Muscat flavor, and a major QTL was co-localized with the 1-deoxy-D-xylulose 5-phosphate synthase (VvDXS) gene, encoding for the 1deoxy-D-xylulose 5-phosphate synthase enzyme, which is involved in the plastidial pathway of terpene biosynthesis (Battilana et al, 2009;Emanuelli et al, 2010;Li et al, 2023). Our results are difficult to interpret, and further genetic studies of this trait and its heritability will be carried out in the future.…”

Decoding strawberry volatile cultivar diversity through comparative transcriptome analysis

“…Key components of strawberry aroma include esters, lactones, acids, furanones, terpenes, and sulfur compounds, with specific metabolites such as ethyl butanoate, methyl butanoate, mesifurane (DMMF), furaneol (DMHF), linalool, nerolidol, γ-decalactone, butanoic acid, and hexanoic acid significantly contributing to the organoleptic profile of strawberries [6][7][8][9][10]. The biosynthesis of these secondary metabolites is regulated through various biochemical pathways, including amino acid metabolism, fatty acid metabolism, and terpenoid metabolism [11,12].…”

HS-SPME-GC/MS Metabolomic Analysis for the Comparative Evaluation between a Plum–Apricot Hybrid and Its Parents

“…Several extraction techniques are used to better evaluate the volatile profile of fruit. Headspace solid-phase microextraction (HS-SPME) together with gas chromatography/mass spectrometry (GC/MS) analysis is commonly performed to report on the aroma of fruits [11]. HS-SPME is considered especially suitable for volatile and semi-volatile profiling [12].…”