Norisoprenoid Compounds Research Articles

Effect of Cluster-Zone Leaf Removal at Different Stages on Cabernet Sauvignon and Marselan (Vitis vinifera L.) Grape Phenolic and Volatile Profiles.

This study investigated the effect of leaf removal at three stages of grape development on the phenolic and volatile profiles of Cabernet Sauvignon and Marselan grapevines for two consecutive years in the Jieshi Mountain region, an area of eastern China with high summer rainfall. The results indicated that cluster-zone leaf removal generally reduced the titratable acidity of both varieties, but did not affect the total soluble solids of grape berries. Leaf-removal treatments increased the anthocyanin and flavonol content of berries in both varieties. However, in Cabernet Sauvignon, leaf removal negatively affected the norisoprenoid compounds, with a more pronounced impact observed when the leaf removal was conducted at an early stage. This negative effect may be related to a decrease in the levels of violaxanthin and neoxanthin, potential precursors of vitisprine and β-damascenone. In contrast, the removal of leaves had no effect on the norisoprenoid aroma of Marselan grapes.

Impact of meteorological conditions, canopy shading and leaf removal on yield, must quality, and norisoprenoid compounds content in Franciacorta sparkling wine.

Climate change is a major concern in agriculture; in grapevine production, climate change can affect yield and wine quality as they depend on the complex interactions between weather, plant material, and viticultural techniques. Wine characteristics are strongly influenced by microclimate of the canopy affecting primary and secondary metabolites of the grapevine. Air temperature and water availability can influence sugar and acid concentration in grapes and relative wines, and their content of volatile compounds such as norisoprenoids. This becomes relevant in sparkling wine production where grapes are generally harvested at a relatively low pH, high acidity, and low sugar content and where the norisoprenoids significantly contributes to the final aroma of the wine. The effect of climate change on grapevine and wine, therefore, calls for the implementation of on-field adaptation strategies. Among them canopy management through leaf removal and shading have been largely investigated in the wine growing sector. The present study, conducted over 4 years (2010-2013) aims at investigating how leaf removal and artificial shading strategies affect grape maturation, must quality and the production of norisoprenoids, analyzed using an untargeted approach, in sparkling wine. Specifically, this paper investigates the effect of meteorological conditions (i.e., water availability and temperatures) and the effect of leaf removal and shading on Vitis vinifera L. cv. Chardonnay and Pinot noir, which are suitable to produce sparkling wine in the DOCG Franciacorta wine growing area (Lombardy, Italy). The effect of leaf removal and shading practices on norisoprenoids has been the focus of the study. No defoliation and artificial shading treatments play an important role in the preservation of the acidity in warm seasons and this suggests calibrating defoliation activities in relation to the meteorological trend without standardized procedures. This is particularly relevant in the case of sparkling wine, where the acidity is essential to determine wine quality. The enhanced norisoprenoid aromas obtained with a total defoliation represent a further element to direct defoliation and shading strategies. The obtained results increase knowledge about the effect of different defoliation and artificial shading applications in relation to meteorological condition supporting the management decision-making in the Franciacorta wine growing area.

Changes of various quality characteristics and aroma compounds of astragalus honey obtained from different altitudes of Adana‐Turkey

In this study, the effects of different altitudes on the physicochemical properties and aroma compounds of astragalus honey were investigated. As the altitude increased, the moisture content of honey samples decreased. Similarly, as the altitude increased, the acidity and the diastase activity of samples increased. Aroma compounds were identified and quantified using the GC-MS-FID. It was determined that with the increasing altitude, the total amount of the alcohol compounds decreased, and the total amount of the lactone compounds and the norisoprenoid compounds increased with the decreasing altitude. Moreover, 11 different aroma compounds with an odor activity value above one were detected. From these compounds, Limonene, (E)-Linalool oxide, (Z)-Linalool oxide, and acetic acid were determined as the powerful odor active compounds in all of the honey samples. The first data on the change of aroma compounds in honey with the effect of altitude were obtained through this study. Novelty Impact Statement Honey, in which many different plant sources are used in the production by honey bees, is an important food item worldwide with its economic and nutritive value. Aroma compounds play an important role in the quality of honey, which is named according to the plant origin from which it is obtained. Through this study, it has been tried to reveal the relationship between the sensorial quality of honey and climate change depending on changing altitude. Hence, in a climate change scenario, the results obtained from this study can help us know what climatic conditions are best for producing high-quality astragalus honey.

Regionality in Australian Shiraz: compositional and climate measures that relate to key sensory attributes

Background and Aims Regional characters or the ‘terroir’ aspects of Shiraz are not well understood. This study aimed to characterise the chemical composition of wines from sites within six important Australian regions, and the climate profiles of the sites, and to determine how they relate to sensory differences. Methods and Results For 22 commercially produced wines 70 chemical measures and 17 site- and season-specific climate indices were determined. Wines with stalky/cooked vegetal sensory properties had a higher concentration of cinnamate esters and dimethylsulfide, which through multivariate analyses was related to later budburst and time of harvest. Wines with a higher concentration of monoterpenes were associated with floral aroma. High radiation measures were linked to higher tannin, colour density, norisoprenoid compounds and phenylethyl acetate and to stronger dark fruit/dried fruit and tannin/colour attributes. High rainfall indices were generally related to low sensory attribute ratings and compositional measures. From cluster analysis of compositional data, wines were well grouped by region of origin. Conclusions Distinctive chemical fingerprints exist for the regions studied, and their climatic profiles were strongly associated with wine composition, with key compounds influencing sensory differences. Significance of the Study The approach of applying multiple site- and season-specific climate measures and relating these to chemical composition and the characteristic sensory attributes of regional Australian Shiraz wines can help producers better understand and influence the effect of place on their wines.

Key norisoprenoid compounds in wines from early-harvested grapes in view of climate change

In view of climate change, the scheduling of an early harvest may be an agronomic option to limit wine alcohol, provided that a satisfactory content of secondary metabolites can be ensured in grapes. To better understand the link between grape ripening, seasonal trend and wine aroma, the aromatic expression of Barbera and Pinot Noir wines produced with early harvested grapes was assessed. Attention was focused on C13 norisoprenoids during both alcoholic fermentation and after three months of storage. At the end of fermentation, the highest β-damascenone content was detected in wines obtained from less ripe grapes, the content subsequently increased significantly after three months of storage; however, the levels of β-ionone decreased significantly during the same period. The reduction of wine alcohol as a result of harvesting earlier, especially for Barbera, was associated with optimal aromatic levels as well as good technological parameters.

Metabolomic-Based Strategy for Fingerprinting of Sambucus nigra L. Berry Volatile Terpenoids and Norisoprenoids: Influence of Ripening and Cultivar.

The integration of plant metabolomics to support preharvest fruit development studies can provide important insights into the biochemical mechanisms involved and lately support producers on harvesting management. A metabolomic-based strategy for fingerprinting of volatile terpenoids and norisoprenoids from Sambucus nigra L. berries from three cultivars, through ripening, was established. From 42 monoterpenic, 20 sesquiterpenic, and 14 norisoprenoid compounds, 48 compounds are reported for the first time as S. nigra berries components. Chemometric tools revealed that ripening was the factor that influenced more the volatile fraction profile and physicochemical parameters (pH, TS, and TSS), followed by cultivar. For the unripe stages, a higher overall content of the studied metabolites was observed, which gradually decreased over the ripening stages, being consistent for the three cultivars. These trends were mainly ruled by limonene, p-cymene, aromadendrene, β-caryophyllene, and dihydroedulan, which might therefore be used by producers as an additional simple decision making tool in conjunction with physicochemical parameters.

Unveiling Sambucus nigra L. berries terpenic metabolomics by comprehensive two dimensional gas chromatography: On the route of bioactive compounds

Metabolomics has expanded on the study of medicinal plants namely on the secondary metabolites plant profiling, that are linked to diverse health benefits on humans, arising as a suitable approach to evaluate biochemical-mediated responses. Elderberries have been used for generations in folk medicine, with several health benefits being reported [1]. The presence of secondary metabolites that are naturally present on elderberries, namely volatile terpenic [2], and phenolic [3] compounds could explain some of the reported biological activities, and being also responsible for some aspects of elderberries quality [4]. Therefore, the characterization of these compounds is of the major interest to understand elderberries biological properties and quality. However, the inherent complexity of the natural matrices requires analytical tools that solve their complexity, exceeding the capacity of the conventional single separation processes, and thus, limiting a reliable MS identification. Comprehensive two-dimensional gas chromatography arises as a possible solution employing two orthogonal mechanisms to separate the constituents of the sample within a single analysis, thus, increasing the peak capacity. In the present study, the volatile terpenic (mono and sesquiterpenic derivatives) and norisoprenoid compounds from the three major elderberries cultivars ('Sabugueira', 'Sabugueiro' and 'Bastardeira') grown in Portugal (5 ripening stages, collected during two consecutive harvesting years), were characterized by comprehensive two-dimensional gas chromatography. A total of 90 constituents were identified, being distributed over monoterpenic (47), sesquiterpenic (24), and norisoprenoid (19) families. From these, 65 are reported for the first time as S. nigra L. berries components. Harvesting season significantly affected the berries composition (p < 0.05), however, ripening stage and cultivars effects should also be taken into consideration. Acknowledgements: Funding is acknowledged from the European Regional Development Fund (FEDER) through the Competitive Factors Thematic Operational Program (COMPETE) and from the Foundation for Science and Technology (FCT), Portugal, for funding the Research Units QOPNA (Research Unit 62/94 QOPNA, under projects PEst-C/QUI/UI0062/2013; FCOMP-01 – 0124-FEDER-037296), and CICECO (project Pest-C/CTM/LA0011/2013; FCOMP-01 – 0124-FEDER-037271). The authors also thank RegieFrutas – Cooperativa Agricola do Tavora/Varosa for the samples supply, and Eng. Cesar Pereira, Eng. Nuno Dias, and Eng. Joao Trindade for their technical support. Â. Salvador thanks the FCT for the PhD grant (SFRH/BD/73778/2010). Keywords: Metabolomics, elderberries, terpenic compounds, norisoprenoids, SPME, GC × GC-ToFMS

Establishment of the varietal profile of Vitis vinifera L. grape varieties from different geographical regions based on HS-SPME/GC–qMS combined with chemometric tools

The varietal volatile profiles of pulp and skin fractions from the main red and white Vitis vinifera L. grape varieties used in the production of Madeira wine (Portugal) were established by headspace solid phase microextraction (SPME) combined with gas chromatography–quadrupole mass spectrometry (GC–qMS) tandem with chemometric tools. A total of 60 varietal volatile compounds — 27 in pulp and 42 in skin of V. vinifera L. grapes studied, were identified, including 27 monoterpenic, 26 sesquiterpenic and 7 C13 norisoprenoid compounds. Principal Component Analysis (PCA) and Hierarchical Clusters Analysis (HCA) results demonstrated that, independently of grape fractions, a distribution by grape variety (white and red) as well as by Terroir effect, was attained using the varietal volatiles from skin grape fraction. Bual, Malvasia Cândida and Malvasia Branca (white varieties) exhibited different varietal volatile profiles, independently of grape fractions, skin or pulp. This difference could be explained by the highest sesquiterpenic level found in Bual grape variety, and monoterpenic level found in Malvasia Cândida and Malvasia Branca grape varieties. The obtained data suggests that climatic factors, such as altitude, temperature and humidity influenced the varietal profile from the target varieties, as the varietal profile of grapes cultivated at Estreito de Câmara de Lobos (32°39′50.59″N; 16°58′48.28″W) and Jardim da Serra (32°41′42.36″N; 16°59′37.32″W) showed qualitative and quantitative differences (expressed as GC peak area) when compared to varietal profile of grapes cultivated at Estreito da Calheta (32°44′0.09″N; 17°11′14.80″W), independently of the grape fractions (pulp or skin). Moreover, the cultivation of recommended grapes to produce Madeira wines — Malvasia Branca, Terrantez and Bastardo, should be promoted as their varietal volatile profile is quite similar to that found in noble varieties (Malvasia Cândida and Sercial, respectively).

β-Carotene autoxidation: oxygen copolymerization, non-vitamin A products, and immunological activity

Carotenoids are reported to have immunological effects independent of vitamin A activity. Although antioxidant activity has been suggested as a basis of action, the ability of carotenoids to autoxidize to numerous non-vitamin A products with immunological activity is an alternative yet to be fully explored. We have undertaken a systematic study of β-carotene autoxidation and tested the product mixture for immunological activity. Autoxidation proceeds predominantly by oxygen copolymerization, leading to a defined, reproducible product corresponding to net uptake of almost 8 molar equivalents of oxygen. The product, termed OxC-beta, empirical formula C40H60O15versus C40H56for β-carotene, contains more than 30% oxygen (w/w) and 85% β-carotene oxygen copolymers (w/w) as well as minor amounts of many C8−C18 norisoprenoid compounds. No vitamin A or higher molecular weight norisoprenoids are present. The predominance of polymeric products has not been reported previously. The polymer appears to be a less polymerized form of sporopollenin, a biopolymer found in exines of spores and pollen. Autoxidations of lycopene and canthaxanthin show a similar predominance of polymeric products. OxC-beta exhibits immunological activity in a PCR gene expression array, indicating that carotenoid oxidation produces non-vitamin A products with immunomodulatory potential.

Characterization of aroma-impact compounds in yerba mate (Ilex paraguariensis) using GC–olfactometry and GC–MS

The volatile compounds of 18 yerba mate (YM) commercial brands from Argentina, Brazil, P.araguay and Uruguay were extracted using a Likens–Nickerson simultaneous distillation–extraction (SDE) apparatus, and analyzed by gas chromatography–mass spectrometry (GC–MS). Results showed that a total of 35 major volatile compounds were identified by GC–MS; among them, norisoprenoid compounds. A principal component analysis (PCA) was carried out in order to ascertain the degree of differentiation between samples and which compounds were involved. The results showed three main groups of YM corresponding to the places where they are commercialized. The first group (samples from Paraguay and Argentina) correlated positively with 6-methyl-5-hepten-2-one, octanal and 1-octanol. The second group (YM marketed in Uruguay but produced in Brazil) correlated positively with α- and β-ionone, linalool, nerol, α-terpineol, (Z)-linalool oxide and the aliphatic hydrocarbons undecane, dodecane and heptadecane. The third group (YM produced and marketed in Brazil) correlated positively with 2,4-heptadienal isomers, (E)-linalool oxide and β-cyclocitral. Through a preference test, one commercial brand was selected to be analyzed by gas chromatography–olfactometry (GC–O). Sixteen odor active compounds were perceived by GC–O analysis. It seems that the norisoprenoid compounds and components produced by fatty acid degradation play a vital role in the special aroma of yerba mate.

Quantification by solid phase micro extraction and stable isotope dilution assay of norisoprenoid compounds in red wines obtained from Piedmont rare varieties

A method to identify and quantify megastigmane norisoprenoid compounds in wines was developed using headspace solid phase micro extraction (SPME) coupled with gas-chromatography/mass-spectrometry (GC–MS). Three different compounds were quantified by stable isotope dilution assay (SIDA): β-damascenone, β-ionone and α-ionone.Particular attention was paid to maximising the method’s sensitivity while reducing the extraction time. To optimise the extraction conditions, a statistically designed experiment was performed using extraction time, extraction temperature and ethanol content as operating variables. Five different SPME fibres suitable for the analysis of volatile compounds were compared. This study confirmed that the PDMS/DVB coating performs best for the quantification of β-damascenone and β-ionone, and the crucial influence of ethanol content of the sample on extraction effectiveness. Finally, the optimised method was applied to the study of various wines derived from rare and autochthonous grape varieties of north-western Italy.

Volatile profile of Arbutus unedo L. fruits through ripening stage

Arbutus unedo L. is a Mediterranean shrub used in the production of jams, marmalades and beverages, as well as in traditional medicine. In this work, the effect of ripening on the volatile compounds of the fruits of A. unedo was evaluated, using headspace-solid phase microextraction combined with gas chromatography/ion trap-mass spectrometry. Alcohols are the main component of the volatile fraction of A. unedo fruits, followed by aldehydes and esters. The main volatile compounds identified were ( Z)-3-hexen-1-ol, 1-hexanol, hexanal, ( E)-2-hexenal and hexyl acetate, all formed through the lipoxygenase pathway (LOX). The green odours are progressively replaced during ripening by floral and sweet sensations, due to the decrease in alcohols, aldehydes and esters, resulting in the unmasking of the aromas associated with the minor compounds (mainly monoterpenes and norisoprenoid compounds) that compose A. unedo fruits.

Volatile composition of Brassica oleracea L. var. costata DC leaves using solid‐phase microextraction and gas chromatography/ion trap mass spectrometry

Volatile and semi-volatile components of internal and external leaves of Brassica oleracea L. var. costata DC, grown under different fertilization regimens, were determined by headspace solid-phase microextraction (HS-SPME) combined with gas chromatography/ion trap mass spectrometry (GC/ITMS). Forty-one volatiles and non-volatile components were formally identified and thirty others were tentatively identified. Qualitative and quantitative differences were noticed between internal and external leaves. In general, internal leaves exhibited more aldehydes and sulfur volatile compounds than external ones, and less ketone, terpenes and norisoprenoid compounds. The fertilization regimens influenced considerably the volatile profile. Fertilizations with higher levels of sulfur produced Brassica leaves with more sulfur volatiles. In opposition, N and S fertilization led to leaves with lower levels of norisoprenoids and terpenes.

Nor-isoprenoids profile during port wine ageing?influence of some technological parameters

Nor-isoprenoid compounds, such as β-damascenone, β-ionone, 2,2,6-trimethylcyclohexanone (TCH), 1,1,6-trimethyl-1,2-dihydronaphthalene (TDN) and vitispirane were determined in 14 young port wines and 45 old port wines. As between the two groups of wines levels of these compounds are quite different, an experimental protocol was performed in order to determine which technological parameter (dissolved O2, free SO2 levels, pH and time/temperature) was related with the formation/consumption of these molecules. The five nor-isoprenoids were equally affected by the selected parameters and a similar profile with time was observed. The synergistic effects of increasing temperature and lowering pH had the largest impact. For samples treated with high oxygen regimes (saturation), the levels of all considered nor-isoprenoids decreased after a certain concentration of oxygen consumed (e.g. 10 mg l−1). Nevertheless, during barrel port wine ageing, corresponding to the 45 wines, two different behaviours can be observed: TDN, vitispirane and TCH increase significantly whilst a decrease of levels of β-ionone and β-damascenone with port barrel ageing was observed. It was also calculated that “over 40 year” old port wines have, respectively, 15, 5 and 3 times higher levels of TDN, vitispirane and TCH than the young ports. For these three compounds the respective rates of formation are higher than those of degradation, which suggests a higher number or higher concentration of precursors than those involved for the megastigame C13 nor-isoprenoids β-damascenone and β-ionone.

Volatile norisoprenoids as markers of botanical origin of Sardinian strawberry-tree ( Arbutus unedo L.) honey: Characterisation of aroma compounds by dynamic headspace extraction and gas chromatography–mass spectrometry

In order to characterize and authenticate the aromatic profile of strawberry-tree ( Arbutus unedo L.) honey, a dynamic headspace (DHS) extraction, followed by gas chromatography–mass spectrometry (GC–MS) analysis, was performed on 10 Sardinian strawberry-tree ( Arbutus unedo L.) honey samples. A total of 28 aroma compounds were identified, but only norisoprenoid compounds such as α-isophorone, β-isophorone and 4-oxoisophorone, were recognized as specific floral origin markers of the strawberry-tree honey. The α-isophorone/β-isophorone ratio varied from 4 to 8, whereas the α-isophorone/4-oxoisophorone ratio was found to range from 11 to 20. The DHS extraction method was proposed as a valid alternative to pollen analysis for floral source detection, especially for products like strawberry-tree honey, characterized by a low pollen content.

Nor-isoprenoids profile during port wine ageing—influence of some technological parameters

Nor-isoprenoid compounds, such as β-damascenone, β-ionone, 2,2,6-trimethylcyclohexanone (TCH), 1,1,6-trimethyl-1,2-dihydronaphthalene (TDN) and vitispirane were determined in 14 young port wines and 45 old port wines. As between the two groups of wines levels of these compounds are quite different, an experimental protocol was performed in order to determine which technological parameter (dissolved O 2, free SO 2 levels, pH and time/temperature) was related with the formation/consumption of these molecules. The five nor-isoprenoids were equally affected by the selected parameters and a similar profile with time was observed. The synergistic effects of increasing temperature and lowering pH had the largest impact. For samples treated with high oxygen regimes (saturation), the levels of all considered nor-isoprenoids decreased after a certain concentration of oxygen consumed (e.g. 10 mg l −1). Nevertheless, during barrel port wine ageing, corresponding to the 45 wines, two different behaviours can be observed: TDN, vitispirane and TCH increase significantly whilst a decrease of levels of β-ionone and β-damascenone with port barrel ageing was observed. It was also calculated that “over 40 year” old port wines have, respectively, 15, 5 and 3 times higher levels of TDN, vitispirane and TCH than the young ports. For these three compounds the respective rates of formation are higher than those of degradation, which suggests a higher number or higher concentration of precursors than those involved for the megastigame C13 nor-isoprenoids β-damascenone and β-ionone.

Gaschromatographische Kopfraum-Analyse der erhitzten Chardonnay- und Semillon-Weine

Volatile compounds of Chardonnay and Semillon wines were analysed using a dynamic headspace method based on selective capillary column trapping and gas chromatography with another column. The effect of thermal treatment on the volatile composition of the wines was studied. Some grape derived norisoprenoid compounds, important to the aroma of aged wine, were formed at 45°C by hydrolysis from the glycosidic precursors. The heat treatment increased the proportion of 1,1,6-Trimethy1-1,2-dihydronaphthalene (TDN) and vitispirane in Chardonnay and Semillon wines. Headspace volatiles of model wines, to which the glycosidic fraction of Chardonnay and Semillon juices was added, were also analysed.

Volatile norisoprenoid compounds as constituents of oak woods used in wine and spirit maturation

Thirty-one norisoprenoid compounds have been identified for the first time in model wine extracts of American and Vosges (France) oak woods. Most of the newly recognized oak norisoprenoids have been previously identified in grape products, thus further linking the composition of oak and wines.

The actinidols: nor-isoprenoid compounds in grapes, wines and spirits

The isomeric actinidols, 2,2,6-trimethyl-8-(1-hydroxy)ethyl-7-oxabicyclo[4.3.0]nona-4,9-dienes, have been identified in steam distillates of juices from Vitis vinifera grape vars. Muscat of Alexandria, Chardonnay and Doradillo. The two major isomers of this compound, which were also commonly observed in wines and brandies, were tentatively identified as having a trans-stereochemistry about the dihydrofuran ring in the molecule.

Use of C 18 reversed-phase liquid chromatography for the isolation of monoterpene glycosides and nor-isoprenoid precursors from grape juice and wines

Glycosidic derivatives of monoterpene flavourants of grapes and wines can be preparatively isolated by selective retention on a C 18-bonded reversed-phase adsorbent. These components can thus be concentrated by a factor of 20,000 in a single chromatographic step. Class separation of monoterpene glycosides at different oxidation levels can also be achieved on the reversed-phase adsorbent. Teh process has also led to the discovery of precursors of 2-phenylethanol, benzyl alcohol, damascenone, vitispirane and 1,1,6-trimethyl-1,2-dihydronaphthalene. Additionally, many other related nor-isoprenoid compounds not previously known in grapes have been observed.