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Article

HMGR Modulates Strawberry Fruit Coloration and Aroma Through Regulating Terpenoid and Anthocyanin Pathways

by
Ting Zheng
,
Lingzhu Wei
,
Jiang Xiang
,
Jiang Wu
and
Jianhui Cheng
*
Institute of Horticulture, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China
*
Author to whom correspondence should be addressed.
Foods 2025, 14(7), 1199; https://doi.org/10.3390/foods14071199
Submission received: 25 February 2025 / Revised: 23 March 2025 / Accepted: 25 March 2025 / Published: 29 March 2025
(This article belongs to the Section Plant Foods)
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Abstract

:
HMGR is a crucial enzyme in the biosynthesis of terpenoids. We cloned FaHMGR and found that FaHMGR expression in fruit was significantly higher than other tissues, especially during the coloring stage. Suppression of FaHMGR (FaHMGRR) promoted coloration by increasing anthocyanin content and produced five new components. In contrast, FaHMGR overexpression (FaHMGROE) downregulated most anthocyanin genes and reduced hexanoic acid methyl ester and linalool contents, thereby inhibiting coloring. Transcriptomic and metabolomic analyses showed that DEGs in HMGROE vs. HMGRC (pCAMBIA1302 empty vector transformant serving as a control) were significantly enriched in phenylpropanoid biosynthesis pathway and pathways related to terpenoid metabolism and MeJA, suggesting MeJA as a potential mediator of HMGR’s influence on terpenoid pathways. Additionally, DEGs in HMGRR vs. HMGRC were enriched in anthocyanin biosynthesis, particularly keracyanin and pelargonidin, which may explain the promoted coloration observed in HMGRR. WGCNA analysis identified five module genes with distinct expression patterns in HMGRR and HMGROE, including ERF118 and WRKY12, which may impact fruit quality by regulating HMGR activity.

1. Introduction

As the most abundant class of secondary metabolites in plants, terpenoids play an important role in plant growth and development, environmental adaptation, and fruit quality attributes. As a globally popular berry crop, strawberries (Fragaria ananassa (Weston) Duch.) are well-recognized for their distinctive flavor and nutritional benefits. In the French strawberry cultivar Falandi, nine sesquiterpenes and three triterpenes have been identified. Terpenes are important components of volatile organic compounds (VOCs). Although they constitute only 0.001–0.01% of strawberry weight, these compounds are essential to the fruit’s favorable flavor, with small changes greatly impacting taste [1]. Strawberry fruits produce a favorable aroma, with terpenoids significantly contributing to their aroma profile. Key terpenoids in strawberries include linalool, nerol, menthol, α-pinene, β-myrcene, α-terpineol, and β-phellandrene, which vary across varieties and developmental stages [2]. Among them, linalool and nerol are two major aroma components in strawberries; however, their contents differ significantly between wild (Fragaria × vesca) and cultivated strawberries (Fragaria × ananassa). The terpenoid synthase gene FaNES1, which is highly expressed in cultivated strawberries, catalyzes the conversion of geranyl diphosphate (GPP) and farnesyl diphosphate (FPP) into linalool and nerol [3]. A study by Fan et al. [4] identified grape flavor genes and their regulatory elements using multi-omics. This research implies that the distal region of strawberry Chromosome 3C may be related to the production of multiple terpenes, with FaNES1 significantly correlated with the biosynthesis of linalool, β-myrcene, α-pinene, (E)-β-farnesene, and nerol.
Studies on the disease resistance mechanisms in strawberries suggest terpenes as one of the three crucial metabolites involved in strawberry defense [5]. Xu et al. [6] demonstrated that UV-C exposure induces monoterpene production in strawberry leaves, which interacts with abscisic acid (ABA) to enhance pathogen resistance. Additionally, terpinen-4-ol improves resistance against Botrytis cinerea and soft rot by activating the phenylpropanoid metabolic pathway in strawberry fruits [7]. Triterpene accumulation has also been linked to differential resistance across strawberry varieties exposed to nanoplastics [8]. Moreover, rapid induction of terpenoid synthesis may enhance anthracnose resistance in certain wild strawberry species [9].
Terpenoids are primarily synthesized in plants through two pathways: the mevalonate (MVA) pathway in the cytoplasm and the 2-C-methyl-D-erythritol-4-phosphate (MEP) pathway in the plastids [10]. In the MVA pathway, 3-hydroxy-3-methylglutaryl CoA reductase (HMGR) is the first rate-limiting enzyme and acts as a central regulator in the biosynthesis of cytoplasmic terpenoids [11]. Studies have demonstrated a positive correlation between HMGR activity and the production of diverse terpenoids across virtually all plant species [12,13,14,15]. Upregulation of HMGR and TPS genes has been shown to enhance terpene levels in roses [16]. Terpenoids influenced by HMGR include beneficial compounds such as sterols, rubber, resin, and saponins [17,18,19,20], which improve plant adaptability to adverse environmental conditions [21,22]. HMGR also directly affects the synthesis of sesquiterpene and triterpene aromas and accelerates the accumulation of tetraterpenoid carotenoids in Escherichia coli (E. coli). [23,24,25]. In addition, HMGR also participates in the regulation of anthocyanin accumulation in plants by affecting hormone accumulation and signal transduction. Downregulation of the HMGR gene can positively induce the expression of a variety of hormones and affect the accumulation of anthocyanins [19,24,26]. However, the association between HMGR and quality traits, such as fruit aroma and color, remains poorly understood [26], with no reported studies in strawberries. Given the significance of HMGR in strawberry fruit development and ripening, we cloned FaHMGR in strawberries and examined its expression across various tissues and developmental stages. Moreover, by integrating transcriptomic and metabolomic analyses with transient gene expression, we assessed the effect of FaHMGR on strawberry fruit quality attributes.

2. Materials and Methods

2.1. Plant Materials

Experiments were conducted at the Yangdu Experimental Vineyard, the Zhejiang Academy of Agricultural Science (E 120°24′, N 30°26′), Jiaxing, China. The strawberry plants used in this study were Fragaria × ananassa cv. Benihoppe. Young roots, stems, leaves, petals, and pistils were collected during flowering period, and the fruits were collected at different developmental stages, individually rapidly frozen in liquid nitrogen, and stored at −80 °C for the determination of HMGR gene expression.

2.2. RNA Extraction, cDNA Synthesis, and qRT-PCR

Total RNA was extracted from 0.1 g of each tissue material using the cetyltrimethylammonium bromide (CTAB) method with the FastPure Plant Total RNA Isolation Kit (Vazyme, Nanjing, China). cDNA was synthesized using a HifairII® 1st Strand cDNA Synthesis SuperMix (Yeasen, Shanghai, China). The qRT-PCR reaction consisted of 5 μL SYBR Premix Ex Taq™ (Takara, Beijing, China), 0.3 μL of each primer (10 μM), 2 μL cDNA, and 2.4 μL RNase-free water, for a total volume of 10 μL. Reactions were performed on a LightCycler 1.5 instrument (Roche, Baden, Germany), starting with the preliminary step at 95 °C for 30 s, followed by 35 cycles of 95 °C for 5 s and 58 °C for 35 s [27]. The relative gene expression was calculated using the 2−ΔCt method [10]. Experiments were conducted with three biological and three technical replicates. Gene-specific primers are listed in Table S1.

2.3. Determination of Hormone Contents

The contents of the hormones auxin indole-3-acetic acid (IAA), ABA, gibberellin (GA3), zeatin riboside (ZR), and brassinosteroids (BRs) were determined using an enzyme-linked immunosorbent assay (ELISA), following the instruction by Wang et al. [28]. For hormone extraction, 0.5 g of strawberry fruits were ground in an ice bath with 2 mL of extract solution (80% methanol containing 1 mmol·L−1 BHT). The resulting mixture was diluted to 10 mL, incubated at 4 °C for 4 h, and then centrifuged at 3500 rpm for 8 min. The supernatant was collected and extracted by C-18 solid phase extraction. The eluted sample was transferred to a 10 mL centrifuge tube and freeze-dried before being dissolved in 2 mL of buffer.

2.4. Transient Expression Levels of FaHMGR and FaHMGRi in Strawberries

Full-length coding sequences of FaHMGR and FaHMGRi (see Table S2) were amplified from the cDNA of ‘Benihoppe’ strawberries and cloned into the pCAMBIA1302 vector carrying a 35S promoter (abbreviated as p35S) to generate constructs p35S-FaHMGR-GFP and p35S-FaHMGRi-GFP. For transient expression, these two plasmids and pCAMBIA1302 empty vector were individually mobilized into Agrobacteria (strain EHA105), which were then used to transform strawberries at the green stage [29], generating the transgenic lines FaHMGROE and FaHMGRR, with the pCAMBIA1302 empty vector transformant serving as a control (CK, FaHMGRC). Following confirmation of the expression levels of FaHMGR-GFP and FaHMGRi-GFP by qRT-PCR (gene specific primers are listed in Table S2), the anthocyanin content and aroma components were determined.

2.5. Determination of Anthocyanin and Chlorophyll Content

Chlorophyll content was determined using spectrophotometry. Total anthocyanins were extracted using a methanol–HCl method. Samples of 0.1 g were submerged and incubated overnight in 5 mL of methanol containing 0.1% (v/v) HCl in the dark at room temperature. Anthocyanin content was measured using the PH differential method, with absorbance at 520 and 700 nm recorded using a UV-2550 spectrophotometer (Shimadzu, Kyoto, Japan). The anthocyanin components were determined using liquid chromatography-mass spectrometer (LC-MS), and the peak area was measured to quantify each component [30].

2.6. Determination of the Aroma Components

Aroma components in transgenic strawberries FaHMGROE, FaHMGRR, and FaHMGRC were analyzed using gas chromatography-mass spectrometry (GC-MS). According to the method described by Zheng et al. [30], samples (3 g) were ground, transferred to a 20 mL headspace bottle, and mixed with three milliliters of saturated NaCl solution and 2 μL 3-nonanone (internal standard). The samples were analyzed with a gas chromatograph (TRACE 1310, Thermo Scientific, Shanghai, China) coupled to a triple quadrupole mass spectrometer (TSQ 9000, Thermo Scientific, Shanghai, China). The column temperature was programmed as follows: the initial temperature was set at 50 °C for 6 min and then increased to 250 °C at a rate of 6 °C min−1, and held for 3 min. The MS conditions were as follows: EI mode at voltage 70 eV; ion source temperature at 230 °C; a scanning rate of 2.88 scan·s−1; and a detection range of 29–540 m·z−1, with helium as the carrier gas at a flow rate of 1.0 mL min−1.

2.7. Transcriptomic Analysis

Library preparation and transcriptome sequencing of FaHMGROE, FaHMGRR, and FaHMGRC strawberries were conducted by the Beijing Novogene Technology Corporation (Beijing, China). Differentially expressed gene (DEG) analysis was performed using the DESeq R package (1.18.0) with the following criteria: false discovery rate (FDR) < 0.05, |fold change| ≥ 2, and adjusted p-value < 0.05 [31]. Principal component analysis (PCA) was performed with the gmodels R package. Gene Ontology (GO) enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were performed with the GOseq R 3.12 software package and KOBAS 3.0 software, respectively [32]. A weighted gene correlation network (WGCNA) was constructed based on a hierarchical clustering tree. All treatments included three biological replicates. To validate transcriptomic data, ten DEGs were selected for confirmation via qRT-PCR.

2.8. Metabolomic Profile Detection and Analysis

For metabolome sequencing, fruits of strawberries FaHMGROE, FaHMGRR, and FaHMGRC were individually grounded in liquid nitrogen, and each homogenate was resuspended in pre-chilled 80% methanol and 0.1% formic acid and well vortexed before incubation. The samples were then centrifuged, diluted, and filtered before injection into the LC-MS/MS system. LC-MS/MS analysis was performed using a Vanquish UHPLC system (Thermo Scientific, Shanghai, China) coupled with an Orbitrap Q Exactive HF-X mass spectrometer (Thermo Fisher). Raw data were processed using Compound Finder 3.0 (CD 3.0, Thermo Fisher). Peaks were matched with the mzCloud (https://www.mzcloud.org/, accessed on 20 March 2022) and ChemSpider (http://www.chemspider.com/, accessed on 20 March 2022) databases to obtain accurate qualitative results, with areas measured for quantitative analysis. The statistical analyses were conducted using R (R version R-3.4.3), Python (Python 2.7.6 version), and CentOS (CentOS release 6.6). Positive ion mode (POS) and negative ion mode (NEG) were both used to detect metabolites. The quality control (QC) sample was included to assess system stability, and a blank sample was used to eliminate background ions.

2.9. Statistical Analysis

All data (with at least three replications, n = 3) are presented as means with standard errors of the means (SEMs). Mean ± SEM values for each treatment were calculated using Microsoft Excel (Microsoft Corporation, Albuquerque, NM, USA). Statistical analysis of variance (ANOVA) and Duncan’s multiple range test (p < 0.05) were performed using SPSS 17.0 (SPSS, Inc., Chicago, IL, USA). Figures were generated using Origin Pro 9 (Origin Inc., Northampton, MA, USA).

3. Results

3.1. Expression Characteristics of FaHMGR

To clarify the patterns of FaHMGR accumulation in strawberries, we examined its expression across various tissues and observed significant variation, with the highest level found in fruit tissue, followed by root, flower, stem, pistil, and leaf in descending order (Figure 1A). During fruit development, FaHMGR expression gradually decreased during the fruit enlargement phase (fruit 1 to fruit 3), then began to increase steadily during the fruit whitening phase (fruit 4 to fruit 6), peaking at the onset of fruit coloring (fruit7). The transcription of FaHMGR then decreased as the fruits turned red, reaching its lowest level at fruit mature stage (fruit 10).
Analyses of six hormones across different tissues and at various stages of fruit development revealed that IAA and ABA were significantly more abundant than the other hormones, including GA3, ZR, JA-ME, and BRs. JA-ME levels were slightly lower than those of IAA and ABA, while BR levels were the lowest across examined tissues (Figure 1B). Notably, hormone levels in roots were generally lower than in other tissues, contrasting with the high expression of HMGR in this tissue. At the onset of fruit coloring (fruit 7), levels of GA3, ABA, ZR, JA-ME, and BRs all increased to varying extents and then decreased as fruit coloration progressed (fruit 8).

3.2. Effects of Transient FaHMGR and FaHMGRi Expression on Strawberry Coloration and Aroma

Overexpression of HMGR in strawberries inhibited fruit coloration and reduced anthocyanin content, where opposite phenomena were observed when HMGR was suppressed, with a 3.33 mg·g−1 increase in anthocyanin content compared to the control (Figure 2A). Analysis of anthocyanin components revealed that cyanidin 3-O-(6″-malonyl-3″-glucosyl-glucoside), cyanidin 3-O-glucoside, cyanidin 3-O-rutinoside, cyanidin 3-O-sophoroside, and delphinidin 3-O-rutinoside were present in FaHMGRR strawberries but absent in FaHMGRC and FaHMGROE (Figure 2B). Additionally, the concentrations of other anthocyanin components in FaHMGRR were significantly higher than in both FaHMGRC and FaHMGROE strawberries. Cyanidin 3-O-(6″-p-coumaroyl-glucoside) was only detected in FaHMGROE. Furthermore, the content of ABA in FaHMGRR was significantly higher than in both FaHMGROE and FaHMGRC (Figure 2C). Conversely, the concentrations of BRs, ZR, and GA3 were significantly elevated in FaHMGROE plants compared to FaHMGRR strawberries.
The type and content of aroma compounds are crucial in determining strawberry fruit flavors and distinguishing strawberry varieties. In this study, a total of 93, 84, and 120 aroma compounds—including esters, ketones, aldehydes, alcohols, terpenes, and minor amounts of furans, phenols, and acids—were detected in FaHMGROE, FaHMGRR, and FaHMGRC strawberries, respectively (Figure 3, Table 1). Esters were found to be the dominant aroma components in wild-type strawberries, with hexanoic acid and its methyl ester accounting for 18.96%. Their concentrations decreased in FaHMGROE and FaHMGRR strawberries. Another major component, (Z)-hex-2-enyl acetate, decreased in FaHMGRR strawberries but remained unchanged in FaHMGROE. Linalool, the primary terpene aroma in strawberries, had a content of 0.62% in CK, which decreased to 0.13% and 0.37% in FaHMGROE and FaHMGRR strawberries, respectively. Additionally, other detected terpenes included D-limonene (0.16%) in CK and α-pinene (0.03%), β-pinene (0.05%), α-terpineol (0.01%), and caryophyllene (0.01%) in FaHMGRR strawberries.
The expression levels of genes involved in anthocyanin and aroma formation were assessed in FaHMGROE, FaHMGRR, and FaHMGRC strawberries. The results showed that the expression of key anthocyanin metabolic pathway genes, including FaC4H, FaCHI, FaCHS, FaF3H, FaANS, FaUFGT, FaMYB10, FabHLH143, FaWD40, and FaPAL2, was lowest in FaHMGROE strawberries, whereas Fa4CL, Fa4CL2, and FaDFR increased. In contrast, in FaHMGRR fruits, levels of FaC4H, FaCHS, FaANS, FaUFGT, FaMYB10, FabHLH143, FaWD40, and FaPAL2 were higher than in both CK and FaHMGROE strawberries (Figure 4). This result suggests a negative correlation between FaHMGR level and the anthocyanin accumulation. For aroma synthesis genes, FaCNL, FaPIN, and FaNCED3 exhibited the highest expression in FaHMGROE fruits, while FaDAHPS1, FaDAHPS2, FaNES1, FaOMT, FaCHP1, FaAAT, FaQR, and FaNCED1 showed the lowest expression. When FaHMGR was inhibited, genes FaNES1, FaOMT, FaCHP1, FaAAT, FaQR, and FaNCED1 were significantly upregulated.

3.3. Manipulating FaHMGR Expression Caused Changes in Strawberry Transcription and Metabolism

To determine the transcriptional and metabolic regulatory effects of FaHMGR on strawberries, RNA sequencing (RNA-Seq) and metabolic profiling were performed on the strawberries with transient overexpression or suppression of FaHMGR (HMGROE, HMGRR), with the empty vector transformed plants as the control (HMGRC). RNA sequencing generated approximately 6.6 GB of data and an average of 44,377,805 clean reads (Table S3). Mapping to the strawberry genome database yielded a high coverage of 94.77%, suggesting effective detection of transcriptional changes due to overexpression alteration of FaHMGR in strawberries. To validate RNA-Seq reliability, 10 DEGs were randomly selected for qRT-PCR, which revealed consistent expression patterns of these genes with the sequencing results (Figure S1).
The PCA of the transcriptome data (Figure 5A) revealed that all samples were positioned along the positive axis of PC1, which explained 32.95% of the variance, indicating a strong association among HMGROE, HMGRR, and HMGRC. HMGROE and HMGRR overlapped along PC1, while minimal differences were observed among the three samples along PC2 (17.74%), with HMGRC positioned in the positive axis. As shown in Figure 5B, the correlation among triplicates for each treatment sample was high, exceeding 0.923. T1 showed slightly lower correlations (below 0.97) with the other two replicates. A total of 3811 DEGs were identified across all samples, with 2713 unique to the comparison pair HMGRR vs. HMGRC and 236 unique to HMGROE vs. HMGRC. There were more downregulated genes than upregulated ones in both comparison pairs (Figure 5C). Of these DEGs, 842 were common between HMGRR vs. HMGRC and HMGROE vs. HMGRC. All DEGs showed four distinct expression patterns and were thereby clustered into four groups comprising 1705, 2049, 54, and 3 genes. Most genes exhibited no significant differences between HMGROE and HMGRR but differed from HMGRC. In contrast, genes in cluster 4, including cold-regulated 413 plasma membrane protein 1 (AtCOR413-PM1), were expressed significantly differently between HMGROE and HMGRR (Figure 5D).
GO and KEGG enrichment analyses of the DEGs in HMGRR vs. HMGRC and HMGROE vs. HMGRC were performed to identify the functional roles of the DEGs. GO analysis revealed that these DEGs in both the HMGROE vs. HMGRC and HMGRR vs. HMGRC comparisons showed significant enrichment in the item nutrient reservoir activity (Figure 6A, Table S4). KEGG analysis showed significant enrichment of the DEGs in the phenylpropanoid biosynthesis pathway for HMGROE vs. HMGRC and in the ribosome, DNA replication, and pyruvate metabolism pathways for the HMGRR vs. HMGRC comparison (Figure 6B, Table S4).
Furthermore, WGCNA divided the DEGs into 63 modules (Figure S2). Module–sample relationship analysis identified five modules indicated in Table S5 by the colors dark magenta, honeydew, tan, violet, and white, containing 82, 40, 269, 88, and 102 genes, respectively (Table S5). Genes in each module displayed distinct expression patterns in HMGRR and HMGROE strawberries (Table S5). In the violet module, gene expression was low in HMGRR and high in HMGROE, while the other four modules exhibited the opposite pattern. Notably, two abscisic acid receptors, PYL11 and PYL9, were identified in the dark magenta and honeydew modules. The tan, violet, and white modules contained several enzymes involved in sugar and acid synthesis pathways. Additionally, transcription factors ERF118 and WRKY12 were found in the white module, suggesting that they may play an important role in FaHMGR-mediated effects on fruit quality.
By integrating database comparisons, we conducted qualitative and quantitative analyses of metabolites, identifying a total of 501 components in positive ion mode and 312 in negative ion mode (Table S6). Principal component analysis (PCA) was employed to evaluate the overall metabolic differences between samples (Figure 7A,D), revealing that HMGROE was more closely related to HMGRC than to HMGRR. In positive ion mode, 63 differential metabolites were common to both HMGROE vs. HMGRC and HMGRR vs. HMGRC. Additionally, 70 and 128 unique metabolites were identified in each pairwise comparison, respectively (Figure 7B,E). In the negative ion mode, 30 differential metabolites were shared in the two pairs, with 34 and 70 metabolites uniquely present in each. Further analysis showed that in HMGROE vs. HMGRC, 20 differential metabolites were upregulated and 52 were downregulated in negative ion mode, while 133 were upregulated and 131 were downregulated in positive ion mode. For HMGRR vs. HMGRC, 116 differential metabolites were upregulated and 115 were downregulated in negative ion mode, while 191 were upregulated and 189 were downregulated in positive ion mode. KEGG pathway analysis indicated that most metabolites mapped to the item “Global and overview maps”, with four specific substances associated with the “Metabolism of terpenoids and polyketides” pathway in both negative and positive ion modes (Figure 7C,F).
KEGG analysis of differentially accumulated metabolites (DAMs) identified 30 enriched pathways in HMGROE vs. HMGRC, with significant enrichment in the phenylpropanoid biosynthesis pathway (p value = 0.029) (Table S7). It is worth noting that the DEGs were enriched in the diterpenoid biosynthesis pathway (p value = 0.228), indicating that HMGR overexpression caused DAMs to decrease and affected terpenoid metabolism. For HMGRR vs. HMGRC, 56 pathways were enriched, including ubiquinone and other terpenoid–quinone biosynthesis pathways (p value = 0.500), with specific metabolites such as shikonin linked to the HMGR metabolic pathway. This group was also enriched in the anthocyanin biosynthesis pathway (p value = 0.126), involving metabolites like keracyanin and pelargonidin, which is likely one reason for the enhanced coloration in strawberries under the HMGRR condition. Notably, both HMGROE vs. HMGRC and HMGRR vs. HMGRC were enriched in methyl jasmonate-related pathways, including alpha-linolenic acid metabolism and plant hormone signal transduction (p value = 0.500).

4. Discussion

4.1. Correlation Between HMGR Expression Levels and Strawberry Fruit Quality

Research on HMGR and its influence on fruit quality related to terpenoids remains limited, particularly concerning its effects on fruit color and aroma. The two terpenoid biosynthesis pathways MVA and MEP are not completely isolated, as transporters in the plastid membrane allow metabolite exchange, facilitating a ‘metabolic cross-talk’ [1]. HMGR, which typically catalyzes the conversion of 3-hydroxy-3-methyl-glutaryl-CoA to mevalonic acid in the MVA pathway, has been shown to influence color formation by affecting the MEP pathway and anthocyanin synthesis [10]; it also encodes functional proteins that accelerate carotenoid biosynthesis [23,25]. Consistently, Zheng et al. [10] found that the expression of VvHMGRs in yellow grape varieties was generally higher than in red varieties. HMGR positively regulates terpenoid metabolism, thereby affecting hormone synthesis and indirectly regulating anthocyanin accumulation [24]. Moreover, a truncated form of HMGR (tHMG) was found to increase endogenous sesquiterpenes level by 37-fold and phytoene by 100-fold [33]. Negative regulation of HMGR by phyB and HY5 via interaction with PIF3 may further affect anthocyanin synthesis [19]. In this study, strawberries overexpressing FaHMGR exhibited reduced coloration, along with downregulated expression of most anthocyanin pathway genes. Conversely, HMGR silencing by expressing FaHMGRi promoted strawberry coloration, with anthocyanin content increasing by 3.33 mg·g−1 compared to the control, aligning with findings by Zheng et al. [26] in grape studies.
Strawberry aroma contributes significantly to fruit quality, enhancing consumer appeal and potential health benefits. Strawberry aroma results from a mixture of more than 350 volatile compounds, making it one of the most complex fruit aromas [34]. Volatiles in strawberry aroma include esters, terpenoids, alkanes, alcohols, acids, aldehydes, and ketones, with terpenes providing the main floral notes [35]. The terpenoids responsible for strawberry aroma primarily consist of monoterpenes (C10), sesquiterpenes (C15), and triterpenes (C30). Monoterpenes were the only type detected in this study. The highest diversity of terpenes, especially monoterpenes, was observed in FaHMGRi-expressing strawberries. This finding suggests that inhibiting HMGR expression promotes monoterpene synthesis via the MEP pathway. However, this contrasts with studies in grapes, which indicated a positive correlation between HMGR expression and monoterpene accumulation. This inconsistency suggests species-specific differences in how HMGR influences fruit aroma composition [36].
Beyond color and aroma, HMGR expression also affects fruit size. HMGR impacts early fruit development by regulating MVA synthesis, a role confirmed in studies of melons and tomatoes. Moreover, reduced HMGR activity has been shown to disrupt normal plant development [37,38].

4.2. Key Factors Regulating HMGR Expression

Hormones are important regulators of terpenoid synthesis, functioning by influencing HMGR activity. Several studies have demonstrated that exogenous application of hormones, including ABA and indole-3-acetic acid (IAA), regulates HMGR activity, while CTK counteracts HMGR inhibitors to support cell growth [39,40,41,42]. Zheng et al. [26] found that BR treatment in Kyoho grapes inhibited HMGR expression and promoted fruit coloration. Here, our study showed significantly higher BR levels in FaHMGROE strawberries than in FaHMGRR.
Several key proteins interact with HMGR to regulate its activity, including Protein Phosphatase 2A (PP2A), sucrose nonfermenting-1 (SNF1)-related kinase 1 (SnRK1), HIGH STEROL ESTER 1 (HISE1), Phytoene synthases 1 (PSY1), GATA24, and PHYTOCHROME INTERACTING FACTOR 3 (PIF3). PP2A, a multi-stage regulator of plant HMGR, negatively impacts HMGR activity through post-translational regulation and is involved in signal transduction for hormones such as ABA, IAA, BRs, and ETH [40]. SnRK1 helps maintain energy homeostasis by post-translationally regulating HMGR and TPS5 [43]. Protein HISE1 participates in the downregulation of HMGR to prevent sterol overproduction in the endoplasmic reticulum, as evidenced by the loss-of-function mutant hise1, which displays elevated levels of HMGR and sterol-producing activity [44]. Additionally, tHMG1 complexes with ZmPSY1 and PaCRTI to significantly boost carotenoid accumulation in rice endosperm by enhancing MVA pathway flux and creating a metabolic sink for carotenoids [45]. In Vitis vinifera, twelve amino acid residues of VvGATA24, including Pro218B, directly bind to the GATA-box cis-element of VvHMGR2 to mediate wax terpenoid biosynthesis [46].

4.3. Transcription Factors Related to Terpenoid Synthesis

Terpenoids encompass a diverse range of compounds with intricate metabolic regulation. The synthesis of plant terpenoids is a complex process involving various enzymes encoded by structural genes that catalyze the formation of multiple intermediate and final products in the terpenoid biosynthesis pathways. Regulatory genes are another crucial factor influencing terpenoid accumulation, forming complexes either individually or through interactions, and specifically binding to cis-elements in the promoters of structural genes. These regulatory complexes modulate terpenoid synthesis by upregulating or downregulating the expression of structural genes.
Transcription factors play a critical role in regulating multiple key genes involved in terpenoid metabolism [47]. Identifying these transcription factors contributes to our understanding of plant terpenoid synthetic biology. Six transcription factor families are currently known to be involved in terpenoid production, including AP2/ERF, bHLH, MYB, NAC, WRKY, and bZIP [6,46,48,49]. For example, AaERF1 and AaERF2 bind to CBF2 and RAA motifs in the promoters of ADS and CYP-71AV1 to regulate artemisinin synthesis [50]; in Citrus sinensis, citERF71 activates CitTPS16 geraniol synthase expression by binding to the CitTPS16 promoter [51]. WRKY regulates plant physiological and biochemical processes by modulating signaling pathways such as SA, ABA, JA, and ETH, thereby participating in plant growth, development, and stress responses. In Catharanthus roseus, Gossypium arboretum, and Artemisia annua, WRKY1 has been shown to regulate monoterpene and sesquiterpene synthesis. For instance, CrWRKY1 inhibits CrMYC2 transcription to suppress monoterpene synthase, thereby regulating monoterpene production [52]. GaWRKY1 promotes sesquiterpene synthesis in cotton by upregulating CAD1-A expression [53]; AaWRKY1, induced by MeJA, binds to the W-box cis-acting element of the ADS promoter to enhance artemisinin synthesis in Artemisia annua [54].
Research on HMGR-related transcription factors remains limited, and current knowledge primarily derives from Arabidopsis thaliana. Studies indicate that HY5 and PIF3 act antagonistically to regulate HMGR expression and sterol biosynthesis by physically binding to the AtHMGR2 promoter [55]. In this study, WGCNA analysis suggests that ERF118 and WRKY12 may act as transcription factors that modulate HMGR-related pathways affecting fruit quality.

5. Conclusions

In conclusion, this study offers new insights into the role of HMGR in influencing strawberry fruit coloration and aroma composition (Figure 8). HMGR regulates both the terpenoid and anthocyanin pathways, with its overexpression inhibiting fruit coloration, downregulating most anthocyanin pathway genes, and reducing aroma content. Conversely, suppression of HMGR promoted coloration and led to the identification of five new anthocyanin components. Our work also suggests MeJA as a potential mediator of HMGR’s influence on terpenoid pathways. Additionally, transcription factors ERF118 and WRKY12 potentially regulate HMGR to affect fruit quality. Overall, our findings contribute to the current understanding of terpenoid metabolism and strawberry fruit quality regulation.

Supplementary Materials

The following supporting information can be downloaded at: https://www.mdpi.com/article/10.3390/foods14071199/s1, Figure S1: Comparison of the gene transcription level detected by RNA-sequencing and qRT-PCR. The green columns indicate levels detected by RNA sequencing, and the black lines indicate the qRT-PCR result. Bars represent standard deviations of the means; Figure S2: Gene dendrogram from weighted gene co-expression network analysis (WGCNA). (A) Hierarchical clustering tree illustrating gene relationships. (B) Module–sample correlation showing the strength of associations between modules and samples. (C) Analysis of the expression patterns of differentially expressed genes (DEGs) from selected typical modules; Figure S3: Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis of significantly enriched differentially accumulated metabolites (DAMs) in the comparisons of HMGRR vs. HMGRC and HMGROE vs. HMGRC; Table S1: Primer used for qRT-PCR on strawberry; Table S2: CDs sequence of FaHMGR and FaHMGRi; Table S3: General overview of transcriptome data; Table S4: The GO with the most significant enrichment of DEGs; Table S5: Genes in five main module; Table S6: The metabolites in positive and negative ion mode; Table S7: The KEGG pathways with the most significant enrichment of DEGs.

Author Contributions

Conceptualization, T.Z. and J.C.; methodology, L.W.; software, J.X.; validation, L.W. and J.W.; formal analysis, T.Z.; investigation, L.W.; resources, J.X.; data curation, L.W.; writing—original draft preparation, T.Z.; writing—review and editing, J.W. and J.C.; visualization, J.X.; supervision, J.C.; project administration, J.W.; funding acquisition, T.Z. All authors have read and agreed to the published version of the manuscript.

Funding

This work was supported by the National Natural Science Foundation of China (32202414).

Institutional Review Board Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

All transcriptomic raw data reported in this paper have been deposited in the National Center for Biotechnology Information sequence read archive (transcriptome sequencing accession SRA accession number: PRJNA781262).

Conflicts of Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

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Figure 1. Expression of FaHMGR (A) and hormone levels (B) in various tissues and fruits at different developmental stages. Different letters represent significant differences between groups.
Figure 1. Expression of FaHMGR (A) and hormone levels (B) in various tissues and fruits at different developmental stages. Different letters represent significant differences between groups.
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Figure 2. Influence of FaHMGR expression on strawberry fruit development. (A) Fruit development in strawberries transiently overexpressing FaHMGR (FaHMGROE) and FaHMGRi (FaHMGRR), using the pCAMBIA1302 empty vector transformant as a control (CK). The pie chart illustrates the relative chlorophyll (green) and anthocyanin (red) contents in strawberries. (B) Composition of anthocyanins in strawberries with varying FaHMGR levels. Data in the table represent the peak area. (C) Impact of FaHMGR overexpression and suppression on phytohormone levels in strawberries treated as in (A). Different letters represent significant differences between groups.
Figure 2. Influence of FaHMGR expression on strawberry fruit development. (A) Fruit development in strawberries transiently overexpressing FaHMGR (FaHMGROE) and FaHMGRi (FaHMGRR), using the pCAMBIA1302 empty vector transformant as a control (CK). The pie chart illustrates the relative chlorophyll (green) and anthocyanin (red) contents in strawberries. (B) Composition of anthocyanins in strawberries with varying FaHMGR levels. Data in the table represent the peak area. (C) Impact of FaHMGR overexpression and suppression on phytohormone levels in strawberries treated as in (A). Different letters represent significant differences between groups.
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Figure 3. Impact of FaHMGR overexpression and suppression on fruit aroma components in strawberries. The red arrow indicates linalool, which decreased after both FaHMGR overexpression and suppression; and the green indicates methyl hexanoate, another main aroma component, which also showed a decrease in response to changes in FaHMGR expression. (The specific data are presented in Table 1).
Figure 3. Impact of FaHMGR overexpression and suppression on fruit aroma components in strawberries. The red arrow indicates linalool, which decreased after both FaHMGR overexpression and suppression; and the green indicates methyl hexanoate, another main aroma component, which also showed a decrease in response to changes in FaHMGR expression. (The specific data are presented in Table 1).
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Figure 4. Effects of changes in FaHMGR levels on the expression of genes associated with anthocyanin and aroma metabolic pathways following transient overexpression of FaHMGR or suppression via FaHMGRi in strawberries. The pCAMBIA1302 empty vector was used as a control. Different letters represent significant differences between groups.
Figure 4. Effects of changes in FaHMGR levels on the expression of genes associated with anthocyanin and aroma metabolic pathways following transient overexpression of FaHMGR or suppression via FaHMGRi in strawberries. The pCAMBIA1302 empty vector was used as a control. Different letters represent significant differences between groups.
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Figure 5. Differentially expressed genes (DEGs) in strawberries after the overexpression and suppression of FaHMGR in strawberry fruits. (A). Principal component analysis (PCA) scatter plot of transcriptomic profiles from different samples. (B). Correlation coefficient graph showing the relationships among all samples, demonstrating the degree of similarity in gene expression profiles. (C). Venn diagram illustrating the number of DEGs in comparison pairs HMGROE vs. HMGRC and HMGRR vs. HMGRC. (D). Expression patterns of DEGs. The Y-axis represents the p-value and the X-axis represents samples.
Figure 5. Differentially expressed genes (DEGs) in strawberries after the overexpression and suppression of FaHMGR in strawberry fruits. (A). Principal component analysis (PCA) scatter plot of transcriptomic profiles from different samples. (B). Correlation coefficient graph showing the relationships among all samples, demonstrating the degree of similarity in gene expression profiles. (C). Venn diagram illustrating the number of DEGs in comparison pairs HMGROE vs. HMGRC and HMGRR vs. HMGRC. (D). Expression patterns of DEGs. The Y-axis represents the p-value and the X-axis represents samples.
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Figure 6. Gene Ontology (GO) categories (A) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis (B) of significantly enriched DEGs in the comparisons HMGRR vs. HMGRC and HMGROE vs. HMGRC.
Figure 6. Gene Ontology (GO) categories (A) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis (B) of significantly enriched DEGs in the comparisons HMGRR vs. HMGRC and HMGROE vs. HMGRC.
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Figure 7. Differentially accumulated metabolites (DAMs) in negative and positive ion modes (NEG, POS) in strawberries after the overexpression and suppression of FaHMGR in fruits. (A,D). PCA analyses in NEG and POS. Quality control (QC) was an equivalent standard to evaluate the stability and signal response strength of the instrument during metabolite detection. (B,E). Venn diagrams and volcano maps illustrating the differential metabolites and their quantities. (C,F). Kyoto Encyclopedia of Genes and Genomes (KEGG) annotation of identified metabolites in samples.
Figure 7. Differentially accumulated metabolites (DAMs) in negative and positive ion modes (NEG, POS) in strawberries after the overexpression and suppression of FaHMGR in fruits. (A,D). PCA analyses in NEG and POS. Quality control (QC) was an equivalent standard to evaluate the stability and signal response strength of the instrument during metabolite detection. (B,E). Venn diagrams and volcano maps illustrating the differential metabolites and their quantities. (C,F). Kyoto Encyclopedia of Genes and Genomes (KEGG) annotation of identified metabolites in samples.
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Figure 8. Proposed model illustrating the impact of varying HMGR expression levels on transcriptional changes and metabolite profiles linked to strawberry fruit development and aroma production.
Figure 8. Proposed model illustrating the impact of varying HMGR expression levels on transcriptional changes and metabolite profiles linked to strawberry fruit development and aroma production.
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Table 1. Aroma components in the fruits of FaHMGR overexpressing and suppressing strawberry.
Table 1. Aroma components in the fruits of FaHMGR overexpressing and suppressing strawberry.
Component NameRetention TimeReference m/zBP Area Content (%)BP HeightTICFormula (mol ion)CAS No.SIRSISelected Column TypeLibrary NameSample Name
Acetaldehyde1.37144.05510,228,2763,136,768,5940.33%3,100,3335,375,014C2H4O75-07-0958958SemiStandardNonPolarmainlibCK
Oxirane, methyl-, (S)-1.49943.044788,6343,136,768,5940.03%421,8711,257,665C3H6O16088-62-3749749SemiStandardNonPolarmainlibCK
Borane-methyl sulfide complex1.55262.05324,302,3743,136,768,5940.77%11,909,12242,681,680C2H9BS13292-87-0883883SemiStandardNonPolarmainlibCK
Acetic acid, methyl ester1.56643.044419,440,3513,136,768,59413.37%182,866,394265,690,168C3H6O279-20-9945945SemiStandardNonPolarmainlibCK
2,3-Butanedione1.74743.04424,367,0253,136,768,5940.78%6,939,9799,434,886C4H6O2431-03-8938938SemiStandardNonPolarmainlibCK
Ethyl Acetate1.87143.04417,699,2843,136,768,5940.56%6,485,8369,925,005C4H8O2141-78-6917917SemiStandardNonPolarmainlibCK
Trichloromethane1.89583.0595,174,4003,136,768,5940.16%2,556,5969,359,119CHCl367-66-3882882SemiStandardNonPolarmainlibCK
Methyl propionate1.96557.0624,721,5543,136,768,5940.15%1,754,7943,203,729C4H8O2554-12-1938938SemiStandardNonPolarmainlibCK
Isopropyl acetate2.17343.0443,258,7413,136,768,5940.10%1,124,5861,737,864C5H10O2108-21-4873880SemiStandardNonPolarmainlibCK
tert-Butyl N-(tert-butoxy)carbamate2.37157.0625,350,2713,136,768,5940.17%1,991,6564,733,100C9H19NO391426-13-0813874SemiStandardNonPolarmainlibCK
1-Penten-3-one2.37755.07217,020,0883,136,768,5940.54%5,694,1619,297,801C5H8O1629-58-9790802SemiStandardNonPolarmainlibCK
Pentanal2.47144.0559,033,3063,136,768,5940.29%3,480,92011,039,592C5H10O110-62-3822858SemiStandardNonPolarmainlibCK
Butanoic acid, methyl ester2.75643.04457,136,8413,136,768,5941.82%24,499,964109,986,055C5H10O2623-42-7955956SemiStandardNonPolarmainlibCK
2-Pentenal, (E)-3.2855.0722,498,3503,136,768,5940.08%481,6651,778,029C5H8O1576-87-0848848SemiStandardNonPolarmainlibCK
1,3,5-Cycloheptatriene3.47491.07629,830,1213,136,768,5940.95%9,230,97522,270,668C7H8544-25-2905917SemiStandardNonPolarmainlibCK
Acetic acid, methyl ester3.64874.026,258,7283,136,768,5940.20%2,709,7157,687,169C3H6O279-20-9701733SemiStandardNonPolarmainlibCK
Tetrahydropyran Z-10-dodecenoate3.65584.9494,656,4033,136,768,5940.15%1,604,6206,953,261C17H30O3 833954SemiStandardNonPolarmainlibCK
Butanoic acid, 2-methyl-, methyl ester3.65957.06211,981,9883,136,768,5940.38%4,110,84015,056,888C6H12O2868-57-5818819SemiStandardNonPolarmainlibCK
2-Ethyl-3-vinyloxirane4.11569.07711,003,9193,136,768,5940.35%4,576,86212,232,144C6H10O34485-78-4745800SemiStandardNonPolarmainlibCK
Hexanal4.11844.055253,167,2853,136,768,5948.07%100,648,259620,389,646C6H12O66-25-1911911SemiStandardNonPolarmainlibCK
Thiirane, 2,3-dimethyl-, trans-4.19288.0921,585,0673,136,768,5940.05%392,1331,026,424C4H8S5955-98-6718836SemiStandardNonPolarmainlibCK
Cyclotrisiloxane, hexamethyl-4.762207.071752,2293,136,768,5940.02%178,370313,095C6H18O3Si3541-05-9878878SemiStandardNonPolarmainlibCK
Valeric anhydride5.23557.0621,330,4963,136,768,5940.04%291,429911,516C10H18O32082-59-9836850SemiStandardNonPolarmainlibCK
anti-2-Acetoxyacetaldoxime5.5443.0442,799,7973,136,768,5940.09%816,0781,438,606C4H7NO337858-07-4825844SemiStandardNonPolarmainlibCK
2-Hexenal5.54741.0779,243,5963,136,768,5940.29%2,054,38613,409,546C6H10O505-57-7850850SemiStandardNonPolarmainlibCK
Pentanoic acid, 2-methyl-5.74474.02588,1873,136,768,5940.02%340,280743,108C6H12O297-61-0722819SemiStandardNonPolarmainlibCK
Dimethyl ether5.81845.0654,230,0683,136,768,5940.13%696,1241,175,717C2H6O115-10-6734858SemiStandardNonPolarmainlibCK
L-Proline, 5-oxo-, n-propyl ester5.82584.10836,942,5063,136,768,5941.18%7,277,46310,124,336C8H13NO3 661749SemiStandardNonPolarmainlibCK
Hexanoic acid, 2-methyl-5.88974.022,590,8113,136,768,5940.08%842,3031,340,031C7H14O24536-23-6787787SemiStandardNonPolarmainlibCK
Pyridine, 2-chloro-6-(2-furanylmethoxy)-4-(trichloromethyl)-5.96281.1121,945,8133,136,768,5940.06%316,505335,174C11H7Cl4NO270166-48-2714744SemiStandardNonPolarmainlibCK
Cyclopentene, 3-(2-methylpropyl)-5.96967.0475,876,4633,136,768,5940.19%1,096,9121,939,651C9H1637689-12-6735742SemiStandardNonPolarmainlibCK
Ethylbenzene6.14791.0761,762,8583,136,768,5940.06%397,453588,648C8H10100-41-4948948SemiStandardNonPolarmainlibCK
1,6-Diazabicyclo[4.1.0]heptane6.34597.0621,488,4143,136,768,5940.05%509,2841,258,442C5H10N259204-83-0763977SemiStandardNonPolarmainlibCK
trans-2-Hexenol6.36257.06292,259,7353,136,768,5942.94%30,367,473101,595,852C6H12O 884903SemiStandardNonPolarmainlibCK
Oxalic acid, diallyl ester6.46241.07727,095,1463,136,768,5940.86%6,951,21813,683,896C8H10O4 721816SemiStandardNonPolarmainlibCK
Cyclopropane, propyl-6.46556.10442,962,9323,136,768,5941.37%10,633,32132,680,537C6H122415-72-7884895SemiStandardNonPolarmainlibCK
1-Butanol, 3-methyl-, acetate6.81843.0446,409,3553,136,768,5940.20%2,001,7455,619,575C7H14O2123-92-2827827SemiStandardNonPolarmainlibCK
1-Pentyn-3-ol, 3-methyl-6.89869.077752,4823,136,768,5940.02%272,832590,848C6H10O77-75-8731731SemiStandardNonPolarmainlibCK
1-Butanol, 2-methyl-, acetate6.90843.04415,850,5823,136,768,5940.51%4,036,8947,941,204C7H14O2624-41-9782785SemiStandardNonPolarmainlibCK
p-Xylene7.37191.0762,053,9243,136,768,5940.07%404,0291,396,190C8H10106-42-3791839SemiStandardNonPolarmainlibCK
Heptanal7.7241.0774,008,5473,136,768,5940.13%1,100,1809,053,170C7H14O111-71-7924924SemiStandardNonPolarmainlibCK
Hexanoic acid, methyl ester8.60874.02594,638,2473,136,768,59418.96%209,731,528712,087,595C7H14O2106-70-7930930SemiStandardNonPolarmainlibCK
Hexanal, 3,3-dimethyl-9.4169.0771,136,4063,136,768,5940.04%312,1521,017,130C8H16O55320-57-5752773SemiStandardNonPolarmainlibCK
2-Heptenal, (Z)-9.73541.0775,834,6943,136,768,5940.19%1,602,96212,007,480C7H12O57266-86-1918935SemiStandardNonPolarmainlibCK
Benzaldehyde9.87377.0612,373,2603,136,768,5940.08%281,8281,048,677C7H6O100-52-7919919SemiStandardNonPolarmainlibCK
1-Hepten-3-one10.53355.0728,347,1603,136,768,5940.27%1,761,3484,809,816C7H12O2918-13-0811821SemiStandardNonPolarmainlibCK
2-Butanone, 3,3-dimethyl-1-thiocyanato-10.58457.0623,952,6453,136,768,5940.13%942,5111,601,979C7H11NOS57518-71-5786889SemiStandardNonPolarmainlibCK
2,6-Octadiene, (E,E)-10.72555.0723,214,1933,136,768,5940.10%871,3211,097,719C8H1418152-31-3678722SemiStandardNonPolarmainlibCK
n-Caproic acid vinyl ester10.73543.04413,091,1603,136,768,5940.42%3,357,2077,194,748C8H14O23050-69-9864869SemiStandardNonPolarmainlibCK
Butane, 2-methoxy-2-methyl-10.79573.0676,468,6823,136,768,5940.21%948,2841,672,954C6H14O994-05-8657660SemiStandardNonPolarmainlibCK
Hexanal, 2,2-dimethyl-10.80543.0441,868,1963,136,768,5940.06%1,084,8914,022,134C8H16O996-12-3696750SemiStandardNonPolarmainlibCK
5-Hepten-2-one, 6-methyl-10.835108.1551,254,2143,136,768,5940.04%282,839859,632C8H14O110-93-0743749SemiStandardNonPolarmainlibCK
Furan, 2-pentyl-10.96681.1126,422,8473,136,768,5940.20%1,509,2742,920,191C9H14O3777-69-3848849SemiStandardNonPolarmainlibCK
Hexanoic acid, ethyl ester11.24888.09210,193,4643,136,768,5940.32%3,080,40819,622,236C8H16O2123-66-0918920SemiStandardNonPolarmainlibCK
Cyclotetrasiloxane, octamethyl-11.318281.07110,866,7873,136,768,5940.35%3,880,32736,434,657C8H24O4Si4556-67-2701825SemiStandardNonPolarmainlibCK
3-Hexen-1-ol, acetate, (E)-11.48243.04434,788,4633,136,768,5941.11%9,403,29032,320,793C8H14O23681-82-1945945SemiStandardNonPolarmainlibCK
Benzene, 1,4-dichloro-11.556145.9932,052,5563,136,768,5940.07%512,2511,534,564C6H4Cl2106-46-7784800SemiStandardNonPolarmainlibCK
1,3-Butadiene, 2-(bromomethyl)-11.67145.993768,2873,136,768,5940.02%244,661517,173C5H7Br23691-13-6717883SemiStandardNonPolarmainlibCK
Cyclopentene, 1-methyl-11.67767.0475,835,7263,136,768,5940.19%2,175,6295,438,968C6H10693-89-0709741SemiStandardNonPolarmainlibCK
Acetic acid, hexyl ester11.68743.044238,634,8323,136,768,5947.61%93,220,548303,592,603C8H16O2142-92-7905905SemiStandardNonPolarmainlibCK
2-Hexen-1-ol, acetate, (Z)-11.77843.044771,471,5833,136,768,59424.59%283,951,144948,479,475C8H14O256922-75-9939939SemiStandardNonPolarmainlibCK
Heptanoic acid, methyl ester12.06674.021,048,0283,136,768,5940.03%288,113568,249C8H16O2106-73-0861861SemiStandardNonPolarmainlibCK
D-Limonene12.13368.101435,0943,136,768,5940.01%80,817298,883C10H165989-27-5841841SemiStandardNonPolarmainlibCK
2-Octenal, (E)-13.03841.0775,066,1763,136,768,5940.16%1,770,34814,822,833C8H14O2548-87-0889889SemiStandardNonPolarmainlibCK
Cyclobutanone, 2,2,3-trimethyl-13.11655.0723,891,7153,136,768,5940.12%1,069,8233,734,900C7H12O1449-49-6695783SemiStandardNonPolarmainlibCK
3(2H)-Furanone, 4-methoxy-2,5-dimethyl-13.12243.0449,714,0313,136,768,5940.31%3,173,63810,830,918C7H10O34077-47-8836840SemiStandardNonPolarmainlibCK
2-Methylthiolane, S,S-dioxide13.48155.072624,6553,136,768,5940.02%176,139508,179C5H10O2S1003-46-9703711SemiStandardNonPolarmainlibCK
Benzoic acid, methyl ester14.145105.0783,032,9553,136,768,5940.10%615,0391,549,722C8H8O293-58-3896898SemiStandardNonPolarmainlibCK
Linalool14.26671.04319,296,3323,136,768,5940.62%7,244,34463,720,248C10H18O78-70-6918919SemiStandardNonPolarmainlibCK
Silane, cyclohexyldimethoxymethyl-14.38105.078721,0183,136,768,5940.02%176,185311,929C9H20O2Si17865-32-6688716SemiStandardNonPolarmainlibCK
Nonanal14.3957.0629,679,1423,136,768,5940.31%3,140,69628,253,366C9H18O124-19-6923923SemiStandardNonPolarmainlibCK
trans-2-Hexenyl propionate14.56157.0621,811,4963,136,768,5940.06%531,265997,049C9H16O2 708744SemiStandardNonPolarmainlibCK
4-Octenoic acid, methyl ester14.74574.02711,7973,136,768,5940.02%225,3321,667,485C9H16O21732-00-9756761SemiStandardNonPolarmainlibCK
Octanoic acid, methyl ester14.96774.0234,512,4263,136,768,5941.10%11,560,04541,147,899C9H18O2111-11-5918919SemiStandardNonPolarmainlibCK
2,6-Nonadienal, (E,Z)-15.75241.077900,9423,136,768,5940.03%264,630872,666C9H14O557-48-2781788SemiStandardNonPolarmainlibCK
Cyclopentasiloxane, decamethyl-15.85573.06777,908,7513,136,768,5942.48%30,176,03573,688,997C10H30O5Si5541-02-6842843SemiStandardNonPolarmainlibCK
trans-2-Nonenal15.90641.0771,701,0153,136,768,5940.05%555,9714,576,612C9H16O 898905SemiStandardNonPolarmainlibCK
Methyl salicylate16.828120.0348,866,3463,136,768,5940.28%1,762,2148,826,263C8H8O3119-36-8827862SemiStandardNonPolarmainlibCK
Decanal17.09641.0771,250,7733,136,768,5940.04%423,3044,082,413C10H20O112-31-2880880SemiStandardNonPolarmainlibCK
2,6-Dimethylbenzaldehyde17.361133.068925,8513,136,768,5940.03%165,452554,758C9H10O1123-56-4759768SemiStandardNonPolarmainlibCK
Valeric anhydride17.91557.062114,4493,136,768,5940.00%58,643203,302C10H18O32082-59-9926950SemiStandardNonPolarmainlibCK
2-Decenal, (Z)-18.47141.077755,1413,136,768,5940.02%246,0462,312,250C10H18O2497-25-8835838SemiStandardNonPolarmainlibCK
Sulfurous acid, 2-ethylhexyl hexyl ester18.90771.043314,1313,136,768,5940.01%117,701523,532C14H30O3S 774786SemiStandardNonPolarmainlibCK
Undecanoic acid, 2-methyl-19.93774.02393,7343,136,768,5940.01%136,862247,713C12H24O224323-25-9770775SemiStandardNonPolarmainlibCK
Cyclohexasiloxane, dodecamethyl-20.02473.06738,778,5123,136,768,5941.24%15,154,94335,504,164C12H36O6Si6540-97-6762765SemiStandardNonPolarmainlibCK
Ethylene glycol Formate Isobutyrate20.58171.043351,6183,136,768,5940.01%117,903221,589C7H12O4 652770SemiStandardNonPolarmainlibCK
Propanoic acid, 2-methyl-, 3-hydroxy-2,2,4-trimethylpentyl ester21.04771.043423,8783,136,768,5940.01%144,998568,661C12H24O377-68-9719719SemiStandardNonPolarmainlibCK
Hexanoic acid, 5-hexenyl ester21.35999.083528,7993,136,768,5940.02%169,016817,205C12H22O2108058-81-7666677SemiStandardNonPolarmainlibCK
3-Hexanone, 2,5-dimethyl-23.66357.062359,4233,136,768,5940.01%140,022502,806C8H16O1888-57-9740780SemiStandardNonPolarmainlibCK
3-Isopropoxy-1,1,1,7,7,7-hexamethyl-3,5,5-tris(trimethylsiloxy)tetrasiloxane23.68673.0675,407,1433,136,768,5940.17%1,953,2615,088,190C18H52O7Si771579-69-6765818SemiStandardNonPolarmainlibCK
Hexanoic acid, octyl ester25.303117.051341,8293,136,768,5940.01%109,562569,397C14H28O24887-30-3708713SemiStandardNonPolarmainlibCK
Propanoic acid, 2-methyl-, anhydride25.62871.0431,908,7273,136,768,5940.06%682,1811,249,241C8H14O397-72-3767926SemiStandardNonPolarmainlibCK
Dibutyl phthalate31.969149.0371,332,3183,136,768,5940.04%418,965608,480C16H22O484-74-2910910SemiStandardNonPolarmainlibCK
Acetaldehyde1.38544.0719,640,6223,272,623,4210.29%2,864,2346,327,558C2H4O75-07-0805805SemiStandardNonPolarmainlibFaHMGR
Butane1.51242.9981,261,8343,272,623,4210.04%649,0861,796,054C4H10106-97-8790793SemiStandardNonPolarmainlibFaHMGR
Borane-methyl sulfide complex1.56662.0536,167,7313,272,623,4211.11%17,531,69364,524,157C2H9BS13292-87-0930930SemiStandardNonPolarmainlibFaHMGR
Acetic acid, methyl ester1.5842.998294,077,4003,272,623,4218.99%125,607,147179,287,826C3H6O279-20-9949949SemiStandardNonPolarmainlibFaHMGR
2,3-Butanedione1.76442.99813,071,0283,272,623,4210.40%3,109,1943,915,474C4H6O2431-03-8952952SemiStandardNonPolarmainlibFaHMGR
Furan, 3-methyl-1.84182.108144,2863,272,623,4210.00%88,401221,706C5H6O930-27-8826840SemiStandardNonPolarmainlibFaHMGR
Furan, 2-methyl-1.88842.9986,131,1333,272,623,4210.19%1,697,9515,257,608C5H6O534-22-5738773SemiStandardNonPolarmainlibFaHMGR
Trichloromethane1.90583.06213,426,7473,272,623,4210.41%6,620,29619,675,151CHCl367-66-3870870SemiStandardNonPolarmainlibFaHMGR
Methyl propionate1.98557.0611,770,9923,272,623,4210.05%613,0451,063,404C4H8O2554-12-1942942SemiStandardNonPolarmainlibFaHMGR
Isopropyl acetate2.19342.9981,365,9483,272,623,4210.04%447,032590,083C5H10O2108-21-4741759SemiStandardNonPolarmainlibFaHMGR
1-Penten-3-one2.39155.0610,172,3893,272,623,4210.31%3,443,7384,971,489C5H8O1629-58-9818821SemiStandardNonPolarmainlibFaHMGR
1H-Tetrazole, 1-methyl-2.47555.066,791,6223,272,623,4210.21%2,269,3622,621,754C2H4N416681-77-9777816SemiStandardNonPolarmainlibFaHMGR
Pentanal2.47844.07126,084,7413,272,623,4210.80%10,759,55335,526,439C5H10O110-62-3882913SemiStandardNonPolarmainlibFaHMGR
Butanoic acid, methyl ester2.77742.99816,128,2283,272,623,4210.49%6,227,01327,953,000C5H10O2623-42-7932935SemiStandardNonPolarmainlibFaHMGR
2-Butenal, 3-methyl-3.30355.062,064,1183,272,623,4210.06%367,7021,100,854C5H8O107-86-8828830SemiStandardNonPolarmainlibFaHMGR
Acetonitrile, (dimethylamino)-3.47883.062356,6303,272,623,4210.01%147,960299,222C4H8N2926-64-7824912SemiStandardNonPolarmainlibFaHMGR
1-Pentanol3.48455.062,141,3123,272,623,4210.07%748,9423,319,244C5H12O71-41-0886886SemiStandardNonPolarmainlibFaHMGR
Toluene3.49491.0838,965,6613,272,623,4210.27%2,260,2234,935,770C7H8108-88-3926926SemiStandardNonPolarmainlibFaHMGR
N-Methyl methacrylamide3.56541.0752,229,7653,272,623,4210.07%518,9601,194,368C5H9NO2/3/3887889905SemiStandardNonPolarmainlibFaHMGR
Butanoic acid, 2-methyl-, methyl ester3.68288.0775,763,3533,272,623,4210.18%1,689,1599,071,823C6H12O2868-57-5907907SemiStandardNonPolarmainlibFaHMGR
Hexanal4.13244.071225,447,0183,272,623,4216.89%87,485,022547,532,859C6H12O66-25-1907907SemiStandardNonPolarmainlibFaHMGR
Cyclotrisiloxane, hexamethyl-4.772207.0521,228,3043,272,623,4210.04%295,647571,012C6H18O3Si3541-05-9935935SemiStandardNonPolarmainlibFaHMGR
1,3-Dimethyldiaziridine5.56442.9981,729,5463,272,623,4210.05%520,5842,011,263C3H8N226177-36-6769837SemiStandardNonPolarmainlibFaHMGR
2-Hexenal5.56741.075848,613,1803,272,623,42125.93%178,171,211939,487,340C6H10O505-57-7814814SemiStandardNonPolarmainlibFaHMGR
2-Pentyn-4-one5.97367.0557,479,3483,272,623,4210.23%1,330,0042,013,814C5H6O7299-55-0742909SemiStandardNonPolarmainlibFaHMGR
Ethylbenzene6.15791.0833,225,2873,272,623,4210.10%698,7411,351,721C8H10100-41-4855855SemiStandardNonPolarmainlibFaHMGR
1,6-Diazabicyclo[4.1.0]heptane6.35297.0682,126,2553,272,623,4210.06%540,022914,250C5H10N259204-83-0919974SemiStandardNonPolarmainlibFaHMGR
trans-2-Hexenol6.36857.06198,249,1493,272,623,4213.00%32,663,168109,460,871C6H12O 889906SemiStandardNonPolarmainlibFaHMGR
Oxalic acid, diallyl ester6.46941.07532,831,9983,272,623,4211.00%7,837,24415,285,797C8H10O4 755838SemiStandardNonPolarmainlibFaHMGR
Formic acid, hexyl ester6.47656.0945,595,7203,272,623,4211.39%11,428,66635,243,625C7H14O2629-33-4783783SemiStandardNonPolarmainlibFaHMGR
L-Proline, propyl ester6.85570.087528,2383,272,623,4210.02%143,026201,618C8H15NO2 674788SemiStandardNonPolarmainlibFaHMGR
1,2,5-Oxadiazole6.94942.9981,606,4313,272,623,4210.05%391,664682,540C2H2N2O288-37-9814973SemiStandardNonPolarmainlibFaHMGR
Benzene, 1,3-dimethyl-7.38191.0832,702,0933,272,623,4210.08%519,7851,462,958C8H10108-38-3853853SemiStandardNonPolarmainlibFaHMGR
Heptanal7.73341.0753,153,0103,272,623,4210.10%828,9336,810,586C7H14O111-71-7866868SemiStandardNonPolarmainlibFaHMGR
Isobutyronitrile8.61268.1051,432,3563,272,623,4210.04%500,7841,148,665C4H7N78-82-0681895SemiStandardNonPolarmainlibFaHMGR
Hexanoic acid, methyl ester8.61974.042205,332,6583,272,623,4216.27%67,468,828237,665,819C7H14O2106-70-7940940SemiStandardNonPolarmainlibFaHMGR
1-Butene, 3,3-dimethyl-9.4269.0671,102,0153,272,623,4210.03%293,4451,147,606C6H12558-37-2658723SemiStandardNonPolarmainlibFaHMGR
2-Heptenal, (Z)-9.74241.0757,343,9933,272,623,4210.22%1,601,57211,419,747C7H12O57266-86-1925932SemiStandardNonPolarmainlibFaHMGR
Benzaldehyde9.8977.0512,156,0583,272,623,4210.07%251,819808,714C7H6O100-52-7881881SemiStandardNonPolarmainlibFaHMGR
2-[(Trimethylsilyl)oxy]-2-{4-[(trimethylsilyl)oxy]phenyl}ethanamine10.121267.018585,0813,272,623,4210.02%184,749491,906C14H27NO2Si2 758775SemiStandardNonPolarmainlibFaHMGR
1-Octen-3-one10.53755.0610,682,5873,272,623,4210.33%2,037,4786,248,689C8H14O4312-99-6816839SemiStandardNonPolarmainlibFaHMGR
1-Octen-3-ol10.58757.0616,189,3223,272,623,4210.19%1,149,7321,860,108C8H16O3391-86-4861862SemiStandardNonPolarmainlibFaHMGR
n-Caproic acid vinyl ester10.73542.99820,068,7563,272,623,4210.61%6,848,05113,296,530C8H14O23050-69-9840840SemiStandardNonPolarmainlibFaHMGR
Butanal, 2-ethyl-10.81942.9989,488,7953,272,623,4210.29%2,144,5535,223,311C6H12O97-96-1738772SemiStandardNonPolarmainlibFaHMGR
Furan, 2-pentyl-10.97681.1293,349,6793,272,623,4210.10%773,2661,394,639C9H14O3777-69-3816818SemiStandardNonPolarmainlibFaHMGR
Cyclohexene, 4-bromo-11.18181.1291,669,6093,272,623,4210.05%323,927562,581C6H9Br3540-84-9809853SemiStandardNonPolarmainlibFaHMGR
Pentanoic acid, 3-methyl-, ethyl ester11.27588.0771,797,1273,272,623,4210.05%439,0732,163,429C8H16O25870-68-8764764SemiStandardNonPolarmainlibFaHMGR
Cyclotetrasiloxane, octamethyl-11.322281.05721,568,5293,272,623,4210.66%7,734,19130,147,085C8H24O4Si4556-67-2837868SemiStandardNonPolarmainlibFaHMGR
Octanal11.33241.0754,362,6503,272,623,4210.13%1,362,0979,387,985C8H16O124-13-0758759SemiStandardNonPolarmainlibFaHMGR
3-Hexen-1-ol, acetate, (Z)-11.48967.05529,061,4743,272,623,4210.89%7,757,15626,984,851C8H14O23681-71-8951951SemiStandardNonPolarmainlibFaHMGR
Benzene, 1,2-dichloro-11.566146.0091,209,3453,272,623,4210.04%291,060912,089C6H4Cl295-50-1904904SemiStandardNonPolarmainlibFaHMGR
Acetic acid, hexyl ester11.69142.998188,907,4633,272,623,4215.77%74,397,820241,243,003C8H16O2142-92-7924924SemiStandardNonPolarmainlibFaHMGR
2-(2-Chloroethyl)-1-methylpyrrolidine11.76484.1134,763,2923,272,623,4210.15%1,355,0001,646,279C7H14ClN 657680SemiStandardNonPolarmainlibFaHMGR
2-Hexen-1-ol, acetate, (Z)-11.78142.998779,875,0463,272,623,42123.83%285,463,039960,584,430C8H14O256922-75-9944944SemiStandardNonPolarmainlibFaHMGR
Heptanoic acid, methyl ester12.07374.042829,7993,272,623,4210.03%203,079381,226C8H16O2106-73-0846846SemiStandardNonPolarmainlibFaHMGR
Bicyclo[3.1.0]hex-2-ene, 4-methyl-1-(1-methylethyl)-12.1493.085293,0253,272,623,4210.01%81,338248,088C10H1628634-89-1794798SemiStandardNonPolarmainlibFaHMGR
2-Octenal, (E)-13.04541.0755,111,8183,272,623,4210.16%1,411,30812,321,524C8H14O2548-87-0888890SemiStandardNonPolarmainlibFaHMGR
3(2H)-Furanone, 4-methoxy-2,5-dimethyl-13.15642.9981,111,8743,272,623,4210.03%381,995805,893C7H10O34077-47-8678680SemiStandardNonPolarmainlibFaHMGR
Cyclobutane, butyl-13.48156.09531,2993,272,623,4210.02%142,971768,839C8H1613152-44-8820820SemiStandardNonPolarmainlibFaHMGR
Linalool14.27671.0744,397,3733,272,623,4210.13%1,536,1631,335,8054C10H18O78-70-6889889SemiStandardNonPolarmainlibFaHMGR
Nonanal14.39757.0615,958,1473,272,623,4210.18%1,808,66016,244,932C9H18O124-19-6918918SemiStandardNonPolarmainlibFaHMGR
Octanoic acid, methyl ester14.97474.04217,452,9853,272,623,4210.53%5,269,29518,430,249C9H18O2111-11-5902916SemiStandardNonPolarmainlibFaHMGR
(+)-2-Bornanone15.5195.068295,9283,272,623,4210.01%106,987385,458C10H16O464-49-3749749SemiStandardNonPolarmainlibFaHMGR
Borane, triethyl-15.76541.075346,6633,272,623,4210.01%137,373349,545C6H15B97-94-9710812SemiStandardNonPolarmainlibFaHMGR
Cyclopentasiloxane, decamethyl-15.85673.058124,765,8193,272,623,4213.81%48,486,461115,043,879C10H30O5Si5541-02-6784785SemiStandardNonPolarmainlibFaHMGR
trans-2-Nonenal15.90941.0751,168,5083,272,623,4210.04%376,2932,893,682C9H16O 851857SemiStandardNonPolarmainlibFaHMGR
Methyl salicylate16.852119.973351,6523,272,623,4210.01%101,413394,817C8H8O3119-36-8746830SemiStandardNonPolarmainlibFaHMGR
2-Decen-1-ol, (E)-17.141.075943,5053,272,623,4210.03%325,3712,781,129C10H20O18409-18-2819826SemiStandardNonPolarmainlibFaHMGR
Acetic acid, octyl ester17.26842.9982,431,0933,272,623,4210.07%513,0031,862,860C10H20O2112-14-1815816SemiStandardNonPolarmainlibFaHMGR
Benzaldehyde, 2,4-dimethyl-17.368133.037463,8733,272,623,4210.01%115,740483,064C9H10O15764-16-6795857SemiStandardNonPolarmainlibFaHMGR
2-Decenal, (E)-18.48270.087367,2983,272,623,4210.01%95,288628,872C10H18O3913-81-3665671SemiStandardNonPolarmainlibFaHMGR
Octane, 6-ethyl-2-methyl-18.90471.074372,6133,272,623,4210.01%126,104553,586C11H2462016-19-7781781SemiStandardNonPolarmainlibFaHMGR
Cyclohexasiloxane, dodecamethyl-20.02473.05855,392,4203,272,623,4211.69%21,681,56052,557,734C12H36O6Si6540-97-6836837SemiStandardNonPolarmainlibFaHMGR
Propanoic acid, 2-methyl-, butyl ester21.05471.074440,7043,272,623,4210.01%144,964349,289C8H16O297-87-0751788SemiStandardNonPolarmainlibFaHMGR
3-Decen-1-ol, acetate, (Z)-21.36642.998176,1613,272,623,4210.01%96,631670,202C12H22O281634-99-3683709SemiStandardNonPolarmainlibFaHMGR
2,2,6,6-Tetramethylheptane21.58757.061215,4173,272,623,4210.01%84,943222,383C11H2440117-45-1798808SemiStandardNonPolarmainlibFaHMGR
Butanoic acid, 3-methyl-, octyl ester22.415103.008262,8683,272,623,4210.01%87,171491,322C13H26O27786-58-5756756SemiStandardNonPolarmainlibFaHMGR
5,9-Undecadien-2-one, 6,10-dimethyl-22.72742.998628,4623,272,623,4210.02%226,763572,169C13H22O689-67-8681681SemiStandardNonPolarmainlibFaHMGR
Sulfurous acid, 2-ethylhexyl hexyl ester23.66657.061439,0013,272,623,4210.01%169,299680,446C14H30O3S 729771SemiStandardNonPolarmainlibFaHMGR
3-Isopropoxy-1,1,1,7,7,7-hexamethyl-3,5,5-tris(trimethylsiloxy)tetrasiloxane23.68673.0587,937,6743,272,623,4210.24%2,936,6737,398,817C18H52O7Si771579-69-6703746SemiStandardNonPolarmainlibFaHMGR
Hexanoic acid, octyl ester25.303117.1361,035,7183,272,623,4210.03%360,4933,382,713C14H28O24887-30-3897898SemiStandardNonPolarmainlibFaHMGR
2,2,4-Trimethyl-1,3-pentanediol diisobutyrate25.62871.0742,266,3493,272,623,4210.07%783,1911,567,931C16H30O46846-50-0736752SemiStandardNonPolarmainlibFaHMGR
Hexasiloxane, tetradecamethyl-26.94373.058845,6263,272,623,4210.03%298,497688,593C14H42O5Si6107-52-8688730SemiStandardNonPolarmainlibFaHMGR
Dibutyl phthalate31.97149.0522,572,7973,272,623,4210.08%837,5641,205,903C16H22O484-74-2920926SemiStandardNonPolarmainlibFaHMGR
Argon1.29840.1036,854,9644,137,136,3470.17%3,660,4093,955,328Ar7440-37-1955999SemiStandardNonPolarmainlibFaHMGRi
Ethanol1.43245.0754,671,5464,137,136,3470.11%2,086,8703,254,898C2H6O64-17-5904904SemiStandardNonPolarmainlibFaHMGRi
Butane1.49943.037868,6584,137,136,3470.02%460,3701,424,518C4H10106-97-8748772SemiStandardNonPolarmainlibFaHMGRi
Borane-methyl sulfide complex1.55362.03925,266,1634,137,136,3470.61%12,159,30845,286,345C2H9BS13292-87-0926926SemiStandardNonPolarmainlibFaHMGRi
Acetic acid, methyl ester1.56643.037195,505,3934,137,136,3474.73%82,683,604117,572,448C3H6O279-20-9929929SemiStandardNonPolarmainlibFaHMGRi
Ethyl Acetate1.87143.03710,377,3844,137,136,3470.25%3,983,9255,951,690C4H8O2141-78-6941941SemiStandardNonPolarmainlibFaHMGRi
Trichloromethane1.89183.0492,086,6564,137,136,3470.05%1,037,1223,787,746CHCl367-66-3856856SemiStandardNonPolarmainlibFaHMGRi
Methyl propionate1.96857.0572,513,5554,137,136,3470.06%913,7281,631,512C4H8O2554-12-1934934SemiStandardNonPolarmainlibFaHMGRi
Isopropyl acetate2.17643.0371,330,2244,137,136,3470.03%578,587866,236C5H10O2108-21-4857857SemiStandardNonPolarmainlibFaHMGRi
tert-Butyl N-(tert-butoxy)carbamate2.36857.0572,938,5394,137,136,3470.07%943,1042,361,586C9H19NO391426-13-0774844SemiStandardNonPolarmainlibFaHMGRi
1-Penten-3-one2.37455.06112,333,1194,137,136,3470.30%4,214,3066,913,990C5H8O1629-58-9741819SemiStandardNonPolarmainlibFaHMGRi
1H-Tetrazole, 1-methyl-2.46155.0615,645,6674,137,136,3470.14%1,874,0132,104,486C2H4N416681-77-9801816SemiStandardNonPolarmainlibFaHMGRi
Pentanal2.46844.06915,452,4214,137,136,3470.37%6,160,35219,016,606C5H10O110-62-3797835SemiStandardNonPolarmainlibFaHMGRi
Butanoic acid, methyl ester2.75743.03743,912,4584,137,136,3471.06%18,739,66883,145,045C5H10O2623-42-7963965SemiStandardNonPolarmainlibFaHMGRi
2-Pentenal, (E)-3.2855.0611,033,2034,137,136,3470.02%367,8891,584,978C5H8O1576-87-0822822SemiStandardNonPolarmainlibFaHMGRi
Toluene3.48491.0675,103,0004,137,136,3470.12%1,264,6523,998,397C7H8108-88-3814848SemiStandardNonPolarmainlibFaHMGRi
Bis(N-methoxy-N-methylamino)methane3.65574.0263,180,5574,137,136,3470.08%1,299,0482,574,569C5H14N2O26919-46-6768810SemiStandardNonPolarmainlibFaHMGRi
Butanoic acid, 4-[(tetrahydro-2H-pyran-2-yl)oxy]-, methyl ester3.66241.0684,706,2864,137,136,3470.11%1,551,1007,651,896C10H18O493691-87-3706707SemiStandardNonPolarmainlibFaHMGRi
Methyl propionate3.66588.0746,374,0274,137,136,3470.15%2,112,1664,925,642C4H8O2554-12-1800800SemiStandardNonPolarmainlibFaHMGRi
Butanoic acid, 3-hydroxy-2-([(4-methylphenyl)sulfonyl]amino)-, methyl ester4.10888.074185,1414,137,136,3470.00%97,115250,846C12H17NO5S 674697SemiStandardNonPolarmainlibFaHMGRi
Hexanal4.11844.069372,453,6054,137,136,3479.00%150,414,036916,289,730C6H12O66-25-1917917SemiStandardNonPolarmainlibFaHMGRi
1-(Ethanesulfonyl)-2-(ethylsulfanyl)ethane4.18588.0742,406,6934,137,136,3470.06%659,6861,828,813C6H14O2S242270-61-1691729SemiStandardNonPolarmainlibFaHMGRi
Cyclotrisiloxane, hexamethyl-4.765207.037964,8664,137,136,3470.02%227,976384,623C6H18O3Si3541-05-9850850SemiStandardNonPolarmainlibFaHMGRi
2-Hexenal, (E)-5.5441.06813,107,9914,137,136,3470.32%3,015,55222,081,879C6H10O6728-26-3884886SemiStandardNonPolarmainlibFaHMGRi
3-Nitro-2-butanol5.74873.054177,1424,137,136,3470.00%99,656207,853C4H9NO36270-16-2736863SemiStandardNonPolarmainlibFaHMGRi
Propene5.84241.0681,362,018,9944,137,136,34732.92%235,005,144592,693,266C3H6115-07-1761826SemiStandardNonPolarmainlibFaHMGRi
Phenol, 2-methoxy-5.96681.1041,381,0944,137,136,3470.03%270,670628,005C7H8O25/1/1990881894SemiStandardNonPolarmainlibFaHMGRi
Difluoromethane6.13751.0741,962,6704,137,136,3470.05%236,123283,406CH2F210/5/1975899987SemiStandardNonPolarmainlibFaHMGRi
4,6-Octadiyn-3-one, 2-methyl-6.15491.0671,921,1394,137,136,3470.05%420,149697,716C9H10O29743-33-7787843SemiStandardNonPolarmainlibFaHMGRi
1H-Pyrazole, 3-ethyl-4,5-dihydro-6.35269.07310,415,3504,137,136,3470.25%3,158,2547,985,625C5H10N25920-29-6661689SemiStandardNonPolarmainlibFaHMGRi
trans-2-Hexenol6.36257.05764,567,1394,137,136,3471.56%20,259,41062,155,133C6H12O 843862SemiStandardNonPolarmainlibFaHMGRi
Methacrolein6.46641.06823,145,9574,137,136,3470.56%5,217,3799,729,342C4H6O78-85-3679725SemiStandardNonPolarmainlibFaHMGRi
Formic acid, hexyl ester6.47256.10329,477,8654,137,136,3470.71%7,235,93622,895,375C7H14O2629-33-4767768SemiStandardNonPolarmainlibFaHMGRi
Propene6.81441.0681,543,8044,137,136,3470.04%422,6021,013,892C3H6115-07-1812904SemiStandardNonPolarmainlibFaHMGRi
1-Butanol, 3-methyl-, acetate6.82843.0373,731,1924,137,136,3470.09%1,134,7942,796,748C7H14O2123-92-2854854SemiStandardNonPolarmainlibFaHMGRi
Oxalic acid, butyl cyclobutyl ester6.90855.0611,994,7464,137,136,3470.05%606,9141,588,198C10H16O4 689717SemiStandardNonPolarmainlibFaHMGRi
1-Butanol, 2-methyl-, acetate6.91543.0378,937,8264,137,136,3470.22%2,167,3454,505,015C7H14O2624-41-9856858SemiStandardNonPolarmainlibFaHMGRi
o-Xylene7.36891.0671,977,7914,137,136,3470.05%424,6761,740,834C8H1095-47-6749860SemiStandardNonPolarmainlibFaHMGRi
Heptanal7.71741.0684,666,5924,137,136,3470.11%1,359,89910,508,931C7H14O111-71-7897897SemiStandardNonPolarmainlibFaHMGRi
Hexanoic acid, methyl ester8.60974.026401,699,9894,137,136,3479.71%142,576,828490,195,832C7H14O2106-70-7924924SemiStandardNonPolarmainlibFaHMGRi
.alpha.-Pinene8.8993.0881,264,4474,137,136,3470.03%408,6101,466,083C10H1680-56-8906908SemiStandardNonPolarmainlibFaHMGRi
Butane9.72943.0372,870,2364,137,136,3470.07%856,6931,201,136C4H10106-97-8744930SemiStandardNonPolarmainlibFaHMGRi
2-Heptenal, (Z)-9.73241.0687,001,0924,137,136,3470.17%1,967,28913,617,963C7H12O57266-86-1897906SemiStandardNonPolarmainlibFaHMGRi
(1H)Pyrrole-2-carbonitrile, 5-methyl-9.88105.0523,531,3944,137,136,3470.09%361,270787,581C6H6N226173-92-2874876SemiStandardNonPolarmainlibFaHMGRi
.beta.-Pinene10.39393.0881,983,4484,137,136,3470.05%675,7612,492,280C10H16127-91-3870870SemiStandardNonPolarmainlibFaHMGRi
(4-Methylphenyl) methanol, neopentyl ether10.51757.057261,1174,137,136,3470.01%134,612398,100C13H20O 695723SemiStandardNonPolarmainlibFaHMGRi
N-(2-Methylacryloyl)imidazola10.5241.0681,808,3224,137,136,3470.04%414,578895,178C7H8N2O54060-80-9652809SemiStandardNonPolarmainlibFaHMGRi
1-Octen-3-one10.52755.06111,924,3074,137,136,3470.29%2,493,0837,011,638C8H14O4312-99-6816830SemiStandardNonPolarmainlibFaHMGRi
Ethylenimine10.57443.0372,015,9024,137,136,3470.05%542,769810,173C2H5N151-56-4691982SemiStandardNonPolarmainlibFaHMGRi
2-Butanone, 3,3-dimethyl-1-thiocyanato-10.58457.0576,454,2614,137,136,3470.16%1,148,9521,830,316C7H11NOS57518-71-5835904SemiStandardNonPolarmainlibFaHMGRi
n-Caproic acid vinyl ester10.72843.03721,920,7674,137,136,3470.53%7,382,07715,020,649C8H14O23050-69-9875876SemiStandardNonPolarmainlibFaHMGRi
Propanoic acid, 2-(aminooxy)-10.76560.049,339,3964,137,136,3470.23%1,192,9002,116,708C3H7NO32786-22-3875914SemiStandardNonPolarmainlibFaHMGRi
Butanal, 2,2-dimethyl-10.81543.0378,467,4814,137,136,3470.20%2,049,9475,827,785C6H12O2094-75-9814839SemiStandardNonPolarmainlibFaHMGRi
5-Hepten-2-one, 6-methyl-10.829108.1291,637,6624,137,136,3470.04%411,8272,156,435C8H14O110-93-0749749SemiStandardNonPolarmainlibFaHMGRi
Furan, 2-pentyl-10.96681.1045,075,8764,137,136,3470.12%1,295,7542,769,505C9H14O3777-69-3889889SemiStandardNonPolarmainlibFaHMGRi
1-Formyl-3-methylaziridine-2-carbonitrile11.23881.1041,619,7534,137,136,3470.04%504,659746,429C5H6N2O 706740SemiStandardNonPolarmainlibFaHMGRi
Hexanoic acid, ethyl ester11.24488.07417,912,7354,137,136,3470.43%5,787,62037,541,037C8H16O2123-66-0914914SemiStandardNonPolarmainlibFaHMGRi
trans-2-(2-Pentenyl)furan11.295107.106365,7574,137,136,3470.01%105,192293,407C9H12O70424-14-5859864SemiStandardNonPolarmainlibFaHMGRi
Butane, 2-chloro-2-methyl-11.30577.058533,4874,137,136,3470.01%132,375242,239C5H11Cl594-36-5734785SemiStandardNonPolarmainlibFaHMGRi
Cyclotetrasiloxane, octamethyl-11.318281.0811,3734,9774,137,136,3470.33%4,759,64950,869,233C8H24O4Si4556-67-2671810SemiStandardNonPolarmainlibFaHMGRi
3-Hexen-1-ol, acetate, (Z)-11.48367.04932,565,0064,137,136,3470.79%8,077,86426,799,716C8H14O23681-71-8936936SemiStandardNonPolarmainlibFaHMGRi
Benzene, 1,2-dichloro-11.556145.9892,077,6734,137,136,3470.05%500,6091,845,266C6H4Cl295-50-1907911SemiStandardNonPolarmainlibFaHMGRi
4-(Benzyl-ethyl-amino)-butyric acid, methyl ester11.66791.067807,8704,137,136,3470.02%188,537407,799C14H21NO2 761877SemiStandardNonPolarmainlibFaHMGRi
Cyclopentene, 4-methyl-11.67767.0496,174,2944,137,136,3470.15%2,216,3386,107,560C6H101759-81-5750793SemiStandardNonPolarmainlibFaHMGRi
Acetic acid, hexyl ester11.68443.037227,652,1454,137,136,3475.50%89,378,323287,956,314C8H16O2142-92-7899899SemiStandardNonPolarmainlibFaHMGRi
2-Hexen-1-ol, acetate, (Z)-11.77843.037771,430,6694,137,136,34718.65%283,039,513957,173,820C8H14O256922-75-9937937SemiStandardNonPolarmainlibFaHMGRi
4-Carene, (1S,3S,6R)-(-)-12.13793.088408,7334,137,136,3470.01%134,988663,001C10H165208-50-4773786SemiStandardNonPolarmainlibFaHMGRi
.beta.-Ocimene12.78493.088700,6364,137,136,3470.02%161,101695,417C10H1613877-91-3837842SemiStandardNonPolarmainlibFaHMGRi
2-Octenal, (E)-13.03941.0685,296,7024,137,136,3470.13%1,877,35816,009,923C8H14O2548-87-0889889SemiStandardNonPolarmainlibFaHMGRi
3(2H)-Furanone, 4-methoxy-2,5-dimethyl-13.11943.03710,334,3974,137,136,3470.25%3,334,59615,441,173C7H10O34077-47-8869873SemiStandardNonPolarmainlibFaHMGRi
1-Octanol13.46856.1031,073,7324,137,136,3470.03%305,9132,006,659C8H18O111-87-5885885SemiStandardNonPolarmainlibFaHMGRi
Hexanal, 2,2-dimethyl-14.11257.057815,3684,137,136,3470.02%241,735681,650C8H16O996-12-3733780SemiStandardNonPolarmainlibFaHMGRi
Benzoic acid, methyl ester14.129105.0527,090,0794,137,136,3470.17%1,610,2774,806,991C8H8O293-58-3905917SemiStandardNonPolarmainlibFaHMGRi
Linalool14.26671.06415,480,0314,137,136,3470.37%5,768,58350,931,632C10H18O78-70-6923924SemiStandardNonPolarmainlibFaHMGRi
Benzoic acid, hydrazide14.3877.0581,022,9494,137,136,3470.02%281,0121,067,233C7H8N2O613-94-5695885SemiStandardNonPolarmainlibFaHMGRi
Nonanal14.38757.05716,764,3294,137,136,3470.41%5,690,90050,590,576C9H18O124-19-6918918SemiStandardNonPolarmainlibFaHMGRi
trans-2-Hexenyl propionate14.56157.0572,036,9274,137,136,3470.05%591,314873,838C9H16O2 658668SemiStandardNonPolarmainlibFaHMGRi
3-Octenoic acid, methyl ester, (E)-14.74974.026346,2794,137,136,3470.01%120,578753,161C9H16O235234-16-3684712SemiStandardNonPolarmainlibFaHMGRi
Octanoic acid, methyl ester14.9774.02621,760,1934,137,136,3470.53%6,910,51524,553,846C9H18O2111-11-5907910SemiStandardNonPolarmainlibFaHMGRi
4-Hydroxymandelic acid, 3TMS derivative14.984267.024273,4374,137,136,3470.01%104,741378,927C17H32O4Si337148-64-4651695SemiStandardNonPolarmainlibFaHMGRi
Bicyclo[2.2.1]heptan-2-one, 1,7,7-trimethyl-, (1S)-15.49795.0591,748,5634,137,136,3470.04%639,8404,001,336C10H16O464-48-2920929SemiStandardNonPolarmainlibFaHMGRi
2,6-Nonadienal, (E,Z)-15.75541.068294,6694,137,136,3470.01%169,269539,930C9H14O557-48-2719722SemiStandardNonPolarmainlibFaHMGRi
Cyclopentasiloxane, decamethyl-15.85673.054121,804,0084,137,136,3472.94%47,422,966117,059,678C10H30O5Si5541-02-6827828SemiStandardNonPolarmainlibFaHMGRi
trans-2-Nonenal15.90641.0681,685,6474,137,136,3470.04%528,6614,017,979C9H16O 905906SemiStandardNonPolarmainlibFaHMGRi
Benzoic acid, ethyl ester16.231105.0521,859,7054,137,136,3470.04%346,985796,009C9H10O293-89-0870870SemiStandardNonPolarmainlibFaHMGRi
.alpha.-Terpineol16.74859.039269,6274,137,136,3470.01%100,389448,396C10H18O98-55-5750752SemiStandardNonPolarmainlibFaHMGRi
Methyl salicylate16.821120.03916,134,6334,137,136,3470.39%3,800,89415,077,032C8H8O3119-36-8935936SemiStandardNonPolarmainlibFaHMGRi
Butyric acid, crotyl ester16.83271.0642,272,5934,137,136,3470.05%591,6431,720,992C8H14O220279-26-9729758SemiStandardNonPolarmainlibFaHMGRi
Octanoic acid, ethyl ester16.89988.074613,3734,137,136,3470.01%150,525321,622C10H20O2106-32-1744744SemiStandardNonPolarmainlibFaHMGRi
[1,2,4]Triazolo[1,5-a]pyrazine17.073120.039560,9304,137,13,63470.01%125,184213,915C5H4N4399-66-6860940SemiStandardNonPolarmainlibFaHMGRi
Decanal17.09341.0682,293,7734,137,136,3470.06%758,1458,191,070C10H20O112-31-2903904SemiStandardNonPolarmainlibFaHMGRi
1-Heptanol, 3-methyl-17.26743.0371,014,0314,137,136,3470.02%310,131801,048C8H18O1070-32-2679685SemiStandardNonPolarmainlibFaHMGRi
2-Ethenoxy-1,7,7-trimethylbicyclo(2.2.1)heptane17.49981.104125,1874,137,136,3470.00%40,126234,154C12H20O 656760SemiStandardNonPolarmainlibFaHMGRi
2-Decenal, (Z)-18.47141.068636,6894,137,136,3470.02%233,9062,195,009C10H18O2497-25-8841843SemiStandardNonPolarmainlibFaHMGRi
6-(3-Methyl)butoxytetrahydro-2H-pyran18.90471.064230,4954,137,136,3470.01%87,921352,977C10H20O2 694716SemiStandardNonPolarmainlibFaHMGRi
Cyclohexasiloxane, dodecamethyl-20.02473.05455,574,3264,137,136,3471.34%21,329,53951,408,783C12H36O6Si6540-97-6792795SemiStandardNonPolarmainlibFaHMGRi
.alpha.-Cubebene20.564105.052501,4624,137,136,3470.01%186,389952,313C15H2417699-14-8854854SemiStandardNonPolarmainlibFaHMGRi
(1R,5R)-2-Methyl-5-((R)-6-methylhept-5-en-2-yl)bicyclo[3.1.0]hex-2-ene21.168119.021182,4524,137,136,3470.00%60,883304,369C15H2458319-06-5769791SemiStandardNonPolarmainlibFaHMGRi
2-Buten-1-one, 1-(2,6,6-trimethyl-1,3-cyclohexadien-1-yl)-, (E)-21.31569.073318,3414,137,136,3470.01%110,800252,442C13H18O23726-93-4825825SemiStandardNonPolarmainlibFaHMGRi
(-)-.beta.-Bourbonene21.37981.104421,3914,137,136,3470.01%127,412414,116C15H245208-59-3727727SemiStandardNonPolarmainlibFaHMGRi
6-(3-Methyl)butoxytetrahydro-2H-pyran21.58471.064186,0914,137,136,3470.00%61,964314,752C10H20O2 663667SemiStandardNonPolarmainlibFaHMGRi
Cycloisolongifolene21.91691.067164,9494,137,136,3470.00%51,322376,142C15H24 742743SemiStandardNonPolarmainlibFaHMGRi
Caryophyllene22.13491.067579,4804,137,136,3470.01%210,3942,226,902C15H2487-44-5836836SemiStandardNonPolarmainlibFaHMGRi
(S,1Z,6Z)-8-Isopropyl-1-methyl-5-methylenecyclodeca-1,6-diene22.54991.067383,7044,137,136,3470.01%112,9481,066,889C15H24317819-80-0757758SemiStandardNonPolarmainlibFaHMGRi
5,9-Undecadien-2-one, 6,10-dimethyl-22.72443.037968,4074,137,136,3470.02%342,784995,993C13H22O689-67-8736736SemiStandardNonPolarmainlibFaHMGRi
3,5-Methanocyclopentapyrazole, 3,3a,4,5,6,6a-hexahydro-3a,4,4-trimethyl-22.85593.088430,4834,137,136,3470.01%156,947492,451C10H16N287143-58-6775816SemiStandardNonPolarmainlibFaHMGRi
Spiro[5.5]undec-2-ene, 3,7,7-trimethyl-11-methylene-, (-)-23.53593.088152,9254,137,136,3470.00%64,003669,362C15H2418431-82-8753753SemiStandardNonPolarmainlibFaHMGRi
3-Hexanone, 2,5-dimethyl-23.66357.057554,8734,137,136,3470.01%212,232910,972C8H16O1888-57-9653753SemiStandardNonPolarmainlibFaHMGRi
3-Isopropoxy-1,1,1,7,7,7-hexamethyl-3,5,5-tris(trimethylsiloxy)tetrasiloxane23.68673.05410,015,8974,137,136,3470.24%3,687,6799,842,576C18H52O7Si771579-69-6754820SemiStandardNonPolarmainlibFaHMGRi
3,3-Dimethyl-1-phenylazetidine23.726105.0521,081,9814,137,136,3470.03%281,038528,043C11H15N22745-26-2804891SemiStandardNonPolarmainlibFaHMGRi
Camphene23.73393.0881,571,9604,137,136,3470.04%459,9343,390,570C10H1679-92-5766820SemiStandardNonPolarmainlibFaHMGRi
2,4-Di-tert-butylphenol23.928191.013332,0784,137,136,3470.01%116,460303,544C14H22O96-76-4701701SemiStandardNonPolarmainlibFaHMGRi
1-Isopropyl-4,7-dimethyl-1,2,3,5,6,8a-hexahydronaphthalene24.243119.021143,3514,137,136,3470.00%52,359396,899C15H2416729-01-4659672SemiStandardNonPolarmainlibFaHMGRi
1,6,10-Dodecatrien-3-ol, 3,7,11-trimethyl-, (E)-24.96169.0731,975,3354,137,136,3470.05%725,7846,612,626C15H26O40716-66-3876880SemiStandardNonPolarmainlibFaHMGRi
Diisoamyl ether25.29970.091349,1804,137,136,3470.01%122,874424,457C10H22O544-01-4686820SemiStandardNonPolarmainlibFaHMGRi
Hexanoic acid, octyl ester25.30343.037553,0304,137,136,3470.01%204,1621,166,904C14H28O24887-30-3667668SemiStandardNonPolarmainlibFaHMGRi
Cyclooctasiloxane, hexadecamethyl-26.94373.0541,296,1284,137,136,3470.03%460,3111,054,423C16H48O8Si8556-68-3708709SemiStandardNonPolarmainlibFaHMGRi
Methanamine, 1,1,1-trifluoro-27.16184.944219,0484,137,136,3470.01%63,443200,316CH2F3N61165-75-1932999SemiStandardNonPolarmainlibFaHMGRi
1,2-Benzenedicarboxylic acid, butyl 2-methylpropyl ester30.434149.036989,7974,137,136,3470.02%328,238463,381C16H22O417851-53-5888896SemiStandardNonPolarmainlibFaHMGRi
Dibutyl phthalate31.966149.0363,920,4834,137,136,3470.09%1,292,1531,990,497C16H22O484-74-2916924SemiStandardNonPolarmainlibFaHMGRi
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MDPI and ACS Style

Zheng, T.; Wei, L.; Xiang, J.; Wu, J.; Cheng, J. HMGR Modulates Strawberry Fruit Coloration and Aroma Through Regulating Terpenoid and Anthocyanin Pathways. Foods 2025, 14, 1199. https://doi.org/10.3390/foods14071199

AMA Style

Zheng T, Wei L, Xiang J, Wu J, Cheng J. HMGR Modulates Strawberry Fruit Coloration and Aroma Through Regulating Terpenoid and Anthocyanin Pathways. Foods. 2025; 14(7):1199. https://doi.org/10.3390/foods14071199

Chicago/Turabian Style

Zheng, Ting, Lingzhu Wei, Jiang Xiang, Jiang Wu, and Jianhui Cheng. 2025. "HMGR Modulates Strawberry Fruit Coloration and Aroma Through Regulating Terpenoid and Anthocyanin Pathways" Foods 14, no. 7: 1199. https://doi.org/10.3390/foods14071199

APA Style

Zheng, T., Wei, L., Xiang, J., Wu, J., & Cheng, J. (2025). HMGR Modulates Strawberry Fruit Coloration and Aroma Through Regulating Terpenoid and Anthocyanin Pathways. Foods, 14(7), 1199. https://doi.org/10.3390/foods14071199

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