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1.
Food Res Int ; 147: 110457, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34399457

RESUMO

Aroma profiles and aroma-active compounds of "Yulu" peach from Fenghua (the peach known for the best flavor and quality in China) were investigated by headspace solid-phase microextraction (HS-SPME), solvent-assisted flavor evaporation (SAFE), gas chromatography-olfactometry (GC-O), gas chromatography-mass spectrometry (GC-MS), and flame photometric detection (FPD). The combination of these methods improved the analysis and identification of aroma substances compared to the combination of a single aroma extraction method and GC-MS. A total of 85 aroma-active compounds, including 10 sulfur compounds were detected. Methional, methyl 3-(methylthio)propionate, methionol, and benzothiazole were first detected in peaches. These aroma compounds cannot only supplement the database of aroma substances of peaches, but also provide data support for traceability of the origins of "Yulu" peaches. In addition, the odor activity value (OAV) was used to identify the contributions of the most important compounds. The results indicated that hexanal, 3-methylbutanal, (E)-2-hexen-1-ol, 3-mercaptohexyl acetate, (E,E)-2,4-decadienal, 2-methylpropanal, γ-decalactone, 2-methylbutanal, theaspirane, and δ-decalactone were the key aroma-active compounds. The key characteristic aroma components were further ascertained by aroma reconstitution and omission experiments, which showed that the fruity, floral, sulfur, and sour notes could be well simulated. Finally, the perceptual interactions between different sulfur compounds and fruity recombination (FR) were explored. 3-mercaptohexanol and 4-methyl-4-mercaptopentan-2-one could significantly decrease the threshold of FR. The possible reason was that these two sulfur compounds had synergistic effects with the aroma compounds in FR, with the U model confirming the results of these synergistic effects. The perceptual interactions provide a basis for the regulation of characteristic fruity aroma of peach products.


Assuntos
Prunus persica , Compostos Orgânicos Voláteis , Cromatografia Gasosa-Espectrometria de Massas , Norisoprenoides , Odorantes/análise , Olfatometria , Compostos Orgânicos Voláteis/análise
2.
Food Chem ; 361: 129781, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34052592

RESUMO

Msalais is produced from local grape juice in southern Xinjiang (China), by concentration and natural fermentation. In the current study, we combined partial least-square regression analysis based on sensory quantitative descriptive and odor active values (OAVs), aroma extract dilution analysis, and aroma recombination and omission tests to delineate the unique aromatic characteristics of traditional Msalais. Msalais has strong dried fruit, fruit jam, and fruity odors, intermediate-strength caramel and baked odors, and weak floral and herbaceous odors, attributed to 24 key aromatic compounds with OAV ≥1 or flavor dilution ≥4. Furaneol, methionol, and 5-methylfurfural greatly contribute to the dried fruit, fruit jam, and caramel odors, respectively. ß-Phenylethyl alcohol mostly contributes to fruit jam odor. ß -Damascenone has a complicated effect on dried fruit, fruit jam, and floral odors. Fruity esters contribute to fruity odor. Floral odor is attributed to terpenes. These findings allow precise improvement of the variable quality of traditional Msalais.


Assuntos
Paladar , Compostos Orgânicos Voláteis/análise , Vinho/análise , Adulto , China , Feminino , Fermentação , Análise de Alimentos/métodos , Análise de Alimentos/estatística & dados numéricos , Furanos/análise , Humanos , Técnicas de Diluição do Indicador , Análise dos Mínimos Quadrados , Masculino , Norisoprenoides/análise , Odorantes/análise , Vitis
3.
Biomolecules ; 11(5)2021 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-33919331

RESUMO

Stress is a major contributing factor of skin aging, which is clinically characterized by wrinkles, loss of elasticity, and dryness. In particular, glucocorticoids are generally considered key hormones for promoting stress-induced skin aging through binding to glucocorticoid receptors (GRs). In this work, we aimed to investigate whether ß-ionone (a compound occurring in various foods such as carrots and almonds) attenuates dexamethasone-induced suppression of collagen and hyaluronic acid synthesis in human dermal fibroblasts, and to explore the mechanisms involved. We found that ß-ionone promoted collagen production dose-dependently and increased mRNA expression levels, including collagen type I α 1 chain (COL1A1) and COL1A2 in dexamethasone-treated human dermal fibroblasts. It also raised hyaluronic acid synthase mRNA expression and hyaluronic acid levels. Notably, ß-ionone inhibited cortisol binding to GR, subsequent dexamethasone-induced GR signaling, and the expression of several GR target genes. Our results reveal the strong potential of ß-ionone for preventing stress-induced skin aging and suggest that its effects are related to the inhibition of GR signaling in human dermal fibroblasts.


Assuntos
Norisoprenoides/metabolismo , Norisoprenoides/farmacologia , Pele/metabolismo , Envelhecimento/efeitos dos fármacos , Envelhecimento/metabolismo , Linhagem Celular , Células Cultivadas , Colágeno/efeitos dos fármacos , Colágeno/metabolismo , Colágeno Tipo I/efeitos dos fármacos , Colágeno Tipo I/metabolismo , Dexametasona/farmacologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/fisiologia , Humanos , Ácido Hialurônico/metabolismo , Transdução de Sinais/efeitos dos fármacos , Pele/efeitos dos fármacos , Envelhecimento da Pele/efeitos dos fármacos , Fator de Crescimento Transformador beta/metabolismo , Raios Ultravioleta
4.
J Am Chem Soc ; 143(17): 6370-6375, 2021 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-33886312

RESUMO

Perovskones and hydrangenones are a family of structurally complex triterpenoids that were mainly isolated from the genus Salvia medicinal plants. These isoprenoids exhibit a broad range of biological activities, such as antitumor and antiplasmodial activities. Here, we report the collective total synthesis of perovskone, perovskones C, D, F, hydrangenone, and hydrangenone B. The key strategies in this work include the following: (1) an asymmetric photoenolization/Diels-Alder reaction was developed to construct a tricyclic ring bearing three contiguous quaternary centers, which was used to build the core icetexane skeleton; (2) a bioinspired Diels-Alder reaction of perovskatone D with trans-α-ocimene was applied to stereospecifically generate perovskones; (3) late-stage oxidations and ring forming steps were developed to synthesize perovskones and hydrangenones. Our synthetic work suggests that (1) perovskatone D may serve as the precursor of the biosynthesis of perovskones and (2) the formation of hydrangenone and hydrangenone B, containing a five-membered D ring, may involve an oxidative ring cleavage and ring regeneration process.


Assuntos
Norisoprenoides/síntese química , Norisoprenoides/metabolismo , Triterpenos/síntese química , Triterpenos/metabolismo , Reação de Cicloadição , Salvia/metabolismo , Estereoisomerismo
5.
Food Funct ; 12(10): 4535-4543, 2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-33903860

RESUMO

Dee are a unique and rapidly growing part of the global snack food market and are recognised as having distinct sensory properties (taste and texture). In this study, the development of important volatile aroma compounds over storage was evaluated and their chemical origin explained. Sweet potatoes were batch fried in high oleic sunflower oil (HOSO) and subjected to accelerated shelf life testing. Headspace volatiles were analysed using SPME GC-MS and correlated with sensory perception. All the components (sweet potatoes, oil and ß-carotene) showed significant degradation after 3 weeks of storage at accelerated conditions (equivalent to 12 weeks in real-time at 25 °C). Marker volatiles associated with lipid oxidation such as hexanal, octanal, pentanal were identified, in addition to norisoprenoids from ß-carotene degradation such as ß-ionon, 5,6-epoxy-ß-ionone, dihydroactinidiolide (DHA) and ß-cyclocitral. The most prominent marker of lipid oxidation (hexanal) rapidly increased at week 1, whereas the carotene degradation makers did not rapidly increase until week 3 suggesting a delayed response. The frying temperature during the batch frying process of SPC was also shown to play a significant role in the sensory perception of the product over the shelf life. Overall, the results suggest that tight control of process variables and raw material design may enable extended shelf life and potentially enhanced health credentials for the product. These findings are unique to SPC, but also of value to the wider food industry.


Assuntos
Ipomoea batatas/anatomia & histologia , Metabolismo dos Lipídeos , Lipídeos , Paladar , beta Caroteno/metabolismo , Aldeídos/análise , Benzofuranos/análise , Culinária , Diterpenos , Indústria Alimentícia , Cromatografia Gasosa-Espectrometria de Massas , Temperatura Alta , Norisoprenoides/análise , Odorantes , Oxirredução , Sensação , Óleo de Girassol , Compostos Orgânicos Voláteis/análise , beta Caroteno/análise
6.
Food Funct ; 12(11): 4797-4807, 2021 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-33861271

RESUMO

Roasting, an important process to refine Wuyi Rock tea, could impart different types of aroma to the final products. This study focuses on the differences in aroma characteristics among three kinds of refined teas, named light fire (LF), moderate fire (MF), and high fire (HF). A combination of solid phase microextraction (SPME) and a switchable system between GC-O-MS and GC × GC-O-MS was utilized to identify the odorants. In total, 97 aroma-active compounds could be smelled at the sniffing port, comprising alcohols, aldehydes, ketones, esters, heterocycles, and terpenes. However, only 52 obtained r-OAV >1. Significant differences were uncovered by the application of principal component analysis (PCA) and partial least squares regression (PLSR). Thereby, MF and HF had a more similar aroma profile, while in LF samples, alcohols, aliphatic aldehydes and some ketones were responsible for the aroma profile, such as (E,E)-2,4-hexadienal, octanal, hexanal, (E,Z)-2,6-nonadienal, (E)-ß-ionone, 3-octen-2-one etc. Strecker aldehydes had a great impact on the aroma of MF, including 2-methylpropanal, 2-methylbutanal, 3-methylbutanal etc. Some N-heterocyclic compounds also affected the overall aroma, for instance, 6-methyl-2-ethylpyrazine. In HF, the majority of aroma compounds increased with increasing roasting temperature, especially N-heterocyclic compounds as well as furfural and 5-methyl-2-furancarboxaldehyde, which are all closely related to the Maillard reaction. Besides, 5-methyl-2-(1-methylethenyl)-4-hexen-1-ol, trans-linalooloxide and 2-nonanone also remarkably influenced the aroma of HF. In addition, it was supposed that most amino acids that participated in the Maillard reaction during roasting were decomposed from the compounds that combined with tea polyphenols and amino acids.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Odorantes/análise , Folhas de Planta/química , Chá/química , Temperatura , Compostos Orgânicos Voláteis/análise , Álcoois , Aldeídos , Norisoprenoides , Polifenóis/análise , Olfato , Microextração em Fase Sólida
7.
Food Chem ; 354: 129504, 2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-33756321

RESUMO

As a worldwide popular drink, black tea has always been one of the main focuses of tea studies. However, few studies have addressed the flavor profiles and related components, and most researches were based on a single factor. This study investigated the effects of multiple brewing conditions (temperature, time, water/tea ratio, and particle size) on the phytochemicals (non-volatile and volatile compounds) and sensory profiles of black tea infusions through response surface methodology. The regression models describing the brewing of detected indexes were significant (p ≤ 0.01) and reliable (R2 ≥ 0.902). The particle size led to the greatest variation of non-volatile compounds and presented negative correlations, while the water/tea ratio affected the composition of volatile compounds the most. Meanwhile, through the addition of the selected aroma compounds (geraniol and ß-ionone), an enhancement of black tea infusion sweetness was observed, proved the existence of odor-taste interaction in black tea infusions.


Assuntos
Monoterpenos Acíclicos/química , Norisoprenoides/química , Percepção Gustatória , Chá/química , Cromatografia Líquida de Alta Pressão , Flavonoides/análise , Humanos , Fenóis/análise , Análise de Componente Principal , Chá/metabolismo , Temperatura , Compostos Orgânicos Voláteis/química , Água/química
8.
J Food Sci ; 86(4): 1258-1272, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33733488

RESUMO

Petit Manseng (Vitis vinifera L.) has become a popular variety in China for the production of semisweet and sweet wines. However, few studies focused on investigating the molecular odor code of its key odorants. In this study, the key odor-active compounds of Chinese sweet Petit Manseng wine were identified by gas chromatography-olfactometry (GC-O) and gas chromatography-mass spectrometry (GC-MS). Fifty-five odorous zones were sniffed and identified by application of aroma extraction dilution analysis on a distillate prepared by liquid-liquid extraction and solvent-assisted flavor evaporation. Among them, isoamyl alcohol, ethyl octanoate, isovaleric acid, (E)-ß-damascenone, and phenylethanol particularly displayed with highest flavor dilution factors above 1024. The quantification of volatiles by headspace solid-phase microextraction coupled with GC-MS and GC coupled with triple quadrupole MS/MS and a calculation of odor activity values (OAVs) indicated 23 volatiles with OAVs above 1. Ethyl hexanoate showed the highest OAV with 208.8, followed by (E)-ß-damascenone (189.0), 3-mercaptohexanol (60.3), isoamyl acetate (45.4), and furaneol (40.1). The aroma of the sweet wine was successfully reconstituted by combining 42 aroma compounds in a model wine solution. 3-Mercaptohexanol, (E)-ß-damascenone, furaneol, γ-octalactone + γ-decalactone + γ-hexalactone, and ethyl cinnamate had important influence on the aroma of sweet Petit Manseng wine assessed by omission tests. Moreover, the discrimination of wines from three regions was successfully achieved by partial least squares discriminant analysis based on quantitative results of key odorants. 3-Mercaptohexanol was considered as the most responsible for the region discrimination and had highest concentrations in Petit Manseng wines from Jiaodong Peninsula. PRACTICAL APPLICATION: Understanding of the knowledge in key odorants of Petit Manseng wines could be useful to improve wine quality through viticultural and enological practices.


Assuntos
Cromatografia Gasosa/métodos , Odorantes/análise , Olfatometria/métodos , Vitis/química , Vinho/análise , Caproatos/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Hexanóis/análise , Norisoprenoides/análise , Compostos de Sulfidrila/análise , Espectrometria de Massas em Tandem , Paladar , Compostos Orgânicos Voláteis/análise , Vinho/classificação
9.
Molecules ; 26(5)2021 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-33673491

RESUMO

Volatile compounds are responsible for driving the aroma of wine. Because of their low perception thresholds, norisoprenoids may play an important role in wine aroma. Studies have shown that ß-damascenone may act as an aroma enhancing compound. However, the direct impact on wine aroma is unclear. Our study examined the direct impact of ß-ionone and ß-damascenone on the aroma sensory perception of Pinot noir wines. Triangle tests were used to determine if assessors could distinguish between wines with varying concentrations of ß-ionone and ß-damascenone in three different Pinot noir wine matrixes. Descriptive analysis was performed on these treatments, perceived as different in triangle tests. Results show that ß-ionone acts as a significant contributor to aromas in Pinot noir wine, as individuals could differentiate both the low and high concentration wines from the control. How ß-ionone impacted wine aroma depends on the wine matrix, as different aroma descriptors were affected based on the model wine used, resulting in floral, red berry or dark berry aromas. The effect of ß-damascenone on Pinot noir aroma was less clear, as perception seems to be heavily influenced by wine matrix composition. This study contributes to our understanding of the complex chemical causation of fruity aromas in Pinot noir wine.


Assuntos
Aromatizantes/análise , Norisoprenoides/química , Odorantes/análise , Vinho/análise , Adulto , Idoso , Feminino , Análise de Alimentos , Indústria Alimentícia , Frutas/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Nova Zelândia , Oregon , Percepção , Sensação , Olfato
10.
J Chem Ecol ; 47(4-5): 444-454, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33683547

RESUMO

Olfactory cues constitute one of the most important plant-pollinator communication channels. Specific chemical components can be associated with specific pollinator functional groups due to pollinator-mediated selection on flower volatile (FV) emission. Here, we used multivariate analyses of FV data to detect an association between FVs and the worldwide distributed pollinator group of the carpenter bees (Xylocopa spp.). We compiled FVs of 29 plant species: 9 pollinated by carpenter bees, 20 pollinated by other bee pollinator functional groups. We tested whether FV emission differed between these groups. To rule out any phylogenetic bias in our dataset, we tested FV emission for phylogenetic signal. Finally, using field assays, we tested the attractive function of two FVs found to be associated with carpenter bees. We found no significant multivariate difference between the two plant groups FVs. However, seven FVs (five apocarotenoid terpenoids, one long-chain alkane and one benzenoid) were significantly associated with carpenter bee pollination, thus being "predictor" compounds of pollination by this pollinator functional group. From those, ß-ionone and (E)-methyl cinnamate presented the highest indicator values and had their behavioural function assessed in field assays. Phylogenetic signal for FVs emission was weak, suggesting that their emission could result from pollinator-mediated selection. In field assays, the apocarotenoid ß-ionone attracted carpenter bees, but also bees from other functional groups. The benzenoid (E)-methyl cinnamate did not attract significant numbers of pollinators. Thus, ß-ionone functions as a non-specific bee attractant, while apocarotenoid FVs emerge as consistent indicators of pollination by large food-foraging bees among bee-pollinated flowers.


Assuntos
Flores/química , Feromônios/química , Polinização/fisiologia , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/metabolismo , Animais , Abelhas , Comportamento Animal , Cinamatos/química , Cinamatos/metabolismo , Preferências Alimentares/fisiologia , Masculino , Análise Multivariada , Norisoprenoides/química , Norisoprenoides/metabolismo , Odorantes , Feromônios/metabolismo , Filogenia , Reprodução
11.
Int J Mol Sci ; 22(3)2021 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-33572582

RESUMO

The abscisic acid (ABA) increase and auxin decline are both indicators of ripening initiation in grape berry, and norisoprenoid accumulation also starts at around the onset of ripening. However, the relationship between ABA, auxin, and norisoprenoids remains largely unknown, especially at the transcriptome level. To investigate the transcriptional and posttranscriptional regulation of the ABA and synthetic auxin 1-naphthaleneacetic acid (NAA) on norisoprenoid production, we performed time-series GC-MS and RNA-seq analyses on Vitis vinifera L. cv. Cabernet Sauvignon grape berries from pre-veraison to ripening. Higher levels of free norisoprenoids were found in ABA-treated mature berries in two consecutive seasons, and both free and total norisoprenoids were significantly increased by NAA in one season. The expression pattern of known norisoprenoid-associated genes in all samples and the up-regulation of specific alternative splicing isoforms of VviDXS and VviCRTISO in NAA-treated berries were predicted to contribute to the norisoprenoid accumulation in ABA and NAA-treated berries. Combined weighted gene co-expression network analysis (WGCNA) and DNA affinity purification sequencing (DAP-seq) analysis suggested that VviGATA26, and the previously identified switch genes of myb RADIALIS (VIT_207s0005g02730) and MAD-box (VIT_213s0158g00100) could be potential regulators of norisoprenoid accumulation. The positive effects of ABA on free norisoprenoids and NAA on total norisoprenoid accumulation were revealed in the commercially ripening berries. Since the endogenous ABA and auxin are sensitive to environmental factors, this finding provides new insights to develop viticultural practices for managing norisoprenoids in vineyards in response to changing climates.


Assuntos
Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Metaboloma/efeitos dos fármacos , Norisoprenoides/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Transcriptoma/efeitos dos fármacos , Vitis/genética , Ácido Abscísico/metabolismo , Processamento Alternativo , Frutas/genética , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Perfilação da Expressão Gênica , Ácidos Indolacéticos/metabolismo , Metabolômica , Ácidos Naftalenoacéticos/metabolismo , Vitis/crescimento & desenvolvimento , Vitis/metabolismo
12.
Chem Senses ; 462021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33347544

RESUMO

Olfactory habituation corresponds to a decreased behavioral or perceptual response to an odor after a prolonged exposure to this odor. Our aim was to investigate whether long-term olfactory habituation and its recovery are similar in young (<35 years old) and older adults (>50). Fifty-seven participants were recruited for a 5-week longitudinal study. They were exposed to one of the two odors (manzanate alpha [MA], irone alpha [IA]) for 2 weeks at home. Olfactory detection thresholds for both odors were measured before and after exposure. Results showed that the two age groups behaved similarly. The long-term exposure to an odor led to a temporary increase of its detection threshold (lower sensitivity to the odor). IA thresholds were more sensitive to the duration of exposure with the odor than MA thresholds. One week after termination of exposure, participants fully recovered and even became more sensitive to both odors. No cross-habituation was found between the two odors. Our findings highlight that long-term habituation is specific to the odor exposed, behaves the same in young and older adults, and is fully reversible in both age groups after 1 week.


Assuntos
Habituação Psicofisiológica/fisiologia , Norisoprenoides/química , Odorantes , Olfato/fisiologia , Adulto , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Limiar Sensorial/fisiologia
13.
Sci Total Environ ; 762: 144539, 2021 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-33360449

RESUMO

ß-Ionone, limonene and longifolene are 3 main components in cyanobacterial volatile organic compounds, which are formed through different pathways and can poison and even kill other algae. To uncover their toxic mechanism from programmed cell death (PCD), the photosynthetic pigments, chlorophyll fluorescence, caspase-like activities, cell size, nuclear variations and DNA ladders were investigated in Chlamydomonas reinhardtii treated with ß-ionone (0.2 mM), limonene (0.2 mM) and longifolene (0.4 mM) at lethal concentration during 24 h. In the treatments with the 3 compounds, the photosynthetic pigments in C. reinhardtii cells gradually degraded, and Fv/Fm gradually decreased and disappeared at 24 h, suggesting that the cell death might be a PCD, due to the physiological activities gradually disappearing. During the cell death, the activities of caspase-9-like and caspase-3-like significantly increased, with the highest at 1 h. With prolonging the treatment time, C. reinhardtii cells gradually shrank, and the nuclei concentrated firstly following by a broken process, with moving to the cell edge. For DNA, obvious ladders were detected at 1 h, and then they gradually degraded to fragments of 100-250 bp at 24 h. These hallmarks suggested that ß-ionone, limonene and longifolene may poison other algae by inducing PCD.


Assuntos
Chlamydomonas reinhardtii , Apoptose , Limoneno , Norisoprenoides , Fotossíntese , Sesquiterpenos
14.
Food Chem ; 338: 128003, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-32932083

RESUMO

UV-C treatment is a commonly known technique to inactivate microorganisms. The objective of this work was to investigate the impact of UV-C treatment of grape must on the sensory characteristics of the resulting wine and on the profile of volatile compounds of grape must and wine. Different UV-C doses were applied to Riesling must and compared with thermal pasteurization. The sensory off-flavor "ATA" and a content of 0.5 µg/L 2-aminoacetophenone were determined in the grape must and in the resulting wine after UV-C treatment with a high dose of 21 kJ/L. Sensory off-flavors did neither occur after thermal pasteurization nor after UV-C treatment with a dose of 2 kJ/L, which is sufficient for the inactivation of microorganisms. Minor changes in the volatiles' profiles of grape must and wine, involving e.g. terpenes and C13-norisoprenoids, occurred in musts treated with thermal pasteurization as well as with a UV-C dose of 2 kJ/L.


Assuntos
Pasteurização , Vitis , Compostos Orgânicos Voláteis/análise , Vinho , Acetofenonas/análise , Monoterpenos Acíclicos/análise , Monoterpenos Acíclicos/química , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Norisoprenoides/análise , Odorantes/análise , Microextração em Fase Sólida/métodos , Paladar , Terpenos/análise , Raios Ultravioleta , Compostos Orgânicos Voláteis/química , Vinho/análise
15.
Food Chem ; 336: 127721, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32763731

RESUMO

The major aroma-active compounds in clear red raspberry juice were identified by molecular sensory science approaches. Thirty-one aroma-active compounds were identified using detection frequency analysis and aroma extract dilution analysis. Among them, 18 volatiles with aroma activity in red raspberry were identified for the first time, while 14 volatiles with odor activity values (OAVs) ≥ 1 were confirmed as the major aroma-active compounds. Three C6 aldehydes showed the highest detection frequencies of 8, and ß-ionone exhibited the highest OAV of 9507 and flavor dilution factor of 512, which indicated that the floral and grassy note could be dominant in overall aroma. Quantitative descriptive analysis suggested that the grassy, floral, woody, and caramel-like notes can be simulated using aroma recombination model 1. Electronic nose analysis also demonstrated that model 1 had closer similarity to the original juice than others. The combination strategy used here would help improve the knowledge of red raspberry aroma.


Assuntos
Aromatizantes/análise , Sucos de Frutas e Vegetais/análise , Rubus/química , Compostos Orgânicos Voláteis/análise , Análise Discriminante , Nariz Eletrônico , Aromatizantes/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas , Norisoprenoides/isolamento & purificação , Análise de Componente Principal , Rubus/metabolismo , Microextração em Fase Sólida , Compostos Orgânicos Voláteis/isolamento & purificação
16.
Molecules ; 25(24)2020 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-33371407

RESUMO

The identification of aroma composition and key odorants contributing to aroma characteristics of white tea is urgently needed, owing to white tea's charming flavors and significant health benefits. In this study, a total of 238 volatile components were identified in the three subtypes of white teas using headspace solid-phase microextraction (HS-SPME) combined with comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry (GC × GC-TOFMS). The multivariate statistical analysis demonstrated that the contents of 103 volatile compounds showed extremely significant differences, of which 44 compounds presented higher contents in Baihaoyinzhen and Baimudan, while the other 59 compounds exhibited higher contents in Shoumei. The sensory evaluation experiment carried out by gas chromatography-olfactometry/mass spectrometry (GC-O/MS) revealed 44 aroma-active compounds, of which 25 compounds were identified, including 9 alcohols, 6 aldehydes, 5 ketones, and 5 other compounds. These odorants mostly presented green, fresh, floral, fruity, or sweet odors. Multivariate analyses of chemical characterization and sensory evaluation results showed that high proportions of alcohols and aldehydes form the basis of green and fresh aroma characteristic of white teas, and phenylethyl alcohol, γ-Nonalactone, trans-ß-ionone, trans-linalool oxide (furanoid), α-ionone, and cis-3-hexenyl butyrate were considered as the key odorants accounting for the different aroma characteristics of the three subtypes of white tea. The results will contribute to in-depth understand chemical and sensory markers associated with different subtypes of white tea, and provide a solid foundation for tea aroma quality control and improvement.


Assuntos
Aromatizantes/química , Odorantes/análise , Chá/química , Monoterpenos Acíclicos/química , Aldeídos/química , Cicloexanóis/química , Frutas/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Norisoprenoides/química , Microextração em Fase Sólida/métodos , Compostos de Tritil/química , Compostos Orgânicos Voláteis/química
17.
Molecules ; 25(24)2020 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-33321809

RESUMO

The term ionone is derived from "iona" (Greek for violet) which refers to the violet scent and "ketone" due to its structure. Ionones can either be chemically synthesized or endogenously produced via asymmetric cleavage of ß-carotene by ß-carotene oxygenase 2 (BCO2). We recently proposed a possible metabolic pathway for the conversion of α-and ß-pinene into α-and ß-ionone. The differences between BCO1 and BCO2 suggest a unique physiological role of BCO2; implying that ß-ionone (one of BCO2 products) is involved in a prospective biological function. This review focuses on the effects of ionones and the postulated mechanisms or signaling cascades involved mediating these effects. ß-Ionone, whether of an endogenous or exogenous origin possesses a range of pharmacological effects including anticancer, chemopreventive, cancer promoting, melanogenesis, anti-inflammatory and antimicrobial actions. ß-Ionone mediates these effects via activation of olfactory receptor (OR51E2) and regulation of the activity or expression of cell cycle regulatory proteins, pro-apoptotic and anti-apoptotic proteins, HMG-CoA reductase and pro-inflammatory mediators. α-Ionone and ß-ionone derivatives exhibit anti-inflammatory, antimicrobial and anticancer effects, however the corresponding structure activity relationships are still inconclusive. Overall, data demonstrates that ionone is a promising scaffold for cancer, inflammation and infectious disease research and thus is more than simply a violet's fragrance.


Assuntos
Norisoprenoides/química , Norisoprenoides/farmacologia , Odorantes , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Vias Biossintéticas , Ciclo Celular/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Fenômenos Químicos , Técnicas de Química Sintética , Mediadores da Inflamação/metabolismo , Norisoprenoides/metabolismo , Ligação Proteica , Receptores Odorantes/metabolismo , Transdução de Sinais/efeitos dos fármacos , Relação Estrutura-Atividade
18.
Zhongguo Zhong Yao Za Zhi ; 45(18): 4341-4348, 2020 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-33164361

RESUMO

Sedum sarmentosum is a traditional Chinese medicine with the clinical effects of clearing away heat and detoxification. It has the pharmacological effects of protecting liver, anti-tumor, anti-fibrosis, anti-oxidation, inhibiting lipid accumulation and immunosuppression. Because of its remarkable effect of reducing enzymes and protecting the liver, it is mainly used for the treatment of various types of hepatitis in clinical application. The flavonoids, megastigmanes, alkaloids, sterols, triterpenes and other chemical constituents in S. sarmentosum are the important material basis for its pharmacological action. In this paper, the research progress on the chemical constituents and pharmacological effects of S. sarmentosum were reviewed, and the research status and research direction of S. sarmentosum were analyzed, in order to provide a reference for its further rational development and application.


Assuntos
Medicamentos de Ervas Chinesas , Sedum , Medicamentos de Ervas Chinesas/farmacologia , Flavonoides , Norisoprenoides , Extratos Vegetais
19.
J Agric Food Chem ; 68(49): 14698-14708, 2020 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-33236890

RESUMO

The hop (Humulus lupulus L.) is an important specialty crop used in beer production. Untargeted UPLC-QTof-MSE metabolomics was used to determine metabolite changes in the leaves of hop plants under varying degrees of drought stress. Principal component analysis revealed that drought treatments produced qualitatively distinct changes in the overall chemical composition of three out of four genotypes tested (i.e., Cascade, Sultana, and a wild var. neomexicanus accession but not Aurora), although differences among treatments were smaller than differences among genotypes. A total of 14 compounds consistently increased or decreased in response to drought stress, and this effect was generally progressive as the severity of drought increased. A total of 10 of these marker compounds were tentatively identified as follows: five glycerolipids, glutaric acid, pheophorbide A, abscisic acid, roseoside, and dihydromyricetin. Some of the observed metabolite changes likely occur across all plants under drought conditions, while others may be specific to hops or to the type of drought treatments performed.


Assuntos
Humulus/metabolismo , Folhas de Planta/química , Metabolismo Secundário , Ácido Abscísico/análise , Ácido Abscísico/metabolismo , Cromatografia Líquida de Alta Pressão , Secas , Genótipo , Glucosídeos/análise , Glucosídeos/metabolismo , Glutaratos/análise , Glutaratos/metabolismo , Humulus/química , Humulus/genética , Espectrometria de Massas , Metabolômica , Norisoprenoides/análise , Norisoprenoides/metabolismo , Folhas de Planta/genética , Folhas de Planta/metabolismo , Água/análise , Água/metabolismo
20.
Food Res Int ; 137: 109688, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33233263

RESUMO

In this study, fruit-zone microclimate was modified by three treatments, including inter-row mulch (M), the combination of leaf removal applied at the onset of veraison and inter-row mulch (MLR-BV), and the combination of leaf removal applied at complete veraison and inter-row mulch (MLR-EV), in a semi-arid climate in three consecutive years (2015-2017). M decreased fruit-zone reflected solar radiation from vineyard floor and low temperature (10-20 °C) duration, whereas it increased soil temperature and high temperature (> 30 °C) duration. MLR-BV and MLR-EV increased fruit-zone incident photosynthetically active radiation while decreased the duration of 20-25 °C compared to M. Notably, M significantly decreased grape total norisoprenoid concentrations in 2015-2017, and total terpenoid concentrations in 2015-2016. Applying leaf removal applied at the onset of veraison could compensate the decreases of total norisoprenoids and terpenoids caused by M when two treatments were applied together. Besides, M significantly increased grape total C6/C9 compound concentrations, besides, (Z)-3-hexen-1-ol concentrations were significantly higher in grapes of M than those of MLR-BV in 2015-2017. Light exposure and high temperature duration after veraison had strong positive correlations with total norisoprenoids and terpenoids, besides, low temperature duration was positively correlated with total norisoprenoids. In addition, light exposure after veraison had strong negative correlations with total C6/C9 compounds. With respect to the volatile compounds in wines, M significantly decreased the concentrations of isopentanol and ethyl acetate, and the concentrations of ethyl cinnamate, phenylacetaldehyde, phenylethyl alcohol and 3-methylthio-1-propanol were significantly lower in MLR-BV and MLR-EV than in M. The outcome of this study can assist winegrowers to properly adjust vineyard managements to optimize the concentrations of desired volatile compounds in grapes and wines.


Assuntos
Vitis , Vinho , Fazendas , Frutas/química , Norisoprenoides/análise , Vinho/análise
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