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1
Lukić, Igor, Nina Išić, Dean Ban, Branka Salopek Sondi e Smiljana Goreta Ban. "Comprehensive Volatilome Signature of Various Brassicaceae Species". Plants 12, n.º 1 (1 de janeiro de 2023): 177. http://dx.doi.org/10.3390/plants12010177.
Resumo:
To investigate in detail the volatilomes of various Brassicaceae species, landraces, and accessions, and to extract specific volatile markers, volatile aroma compounds were isolated from plant samples by headspace solid-phase microextraction and analyzed by gas chromatography/mass spectrometry (HS-SPME-GC/MS). The data obtained were subjected to uni- and multivariate statistical analysis. In general, two cabbage (Brassica oleracea L. var. capitata) landraces emitted the lowest amounts of volatiles generated in the lipoxygenase (LOX) pathway. Wild species Brassica incana Ten. and Brassica mollis Vis. were characterized by relatively high trans-2-hexenal/cis-3-hexen-1-ol ratio in relation to other investigated samples. A Savoy cabbage (Brassica oleracea L. var. sabauda) cultivar and three kale (Brassica oleracea L. var. acephala) accessions exhibited particular similarities in the composition of LOX volatiles, while the LOX volatilome fraction of B. incana and B. mollis partially coincided with that of another wild species, Diplotaxis tenuifolia L. Regarding volatiles formed in the glucosinolate (GSL) pathway, Savoy cabbage and wild species B. incana, B. mollis, and D. tenuifolia showed more intense emission of isothiocyanates than cabbage and kale. Diplotaxis tenuifolia showed a rather limited production of nitriles. The results of this study contribute to the general knowledge about volatile composition from various Brassicaceae species, which could be exploited for their better valorization. Future studies should focus on the influence of various environmental, cultivation, and post-harvest factors to obtain data with a higher level of applicability in practice.
2
Gualtieri, Liberata, Maurilia Maria Monti, Francesca Mele, Assunta Russo, Paolo Alfonso Pedata e Michelina Ruocco. "Volatile Organic Compound (VOC) Profiles of Different Trichoderma Species and Their Potential Application". Journal of Fungi 8, n.º 10 (21 de setembro de 2022): 989. http://dx.doi.org/10.3390/jof8100989.
Resumo:
Fungi emit a broad spectrum of volatile organic compounds (VOCs), sometimes producing species-specific volatile profiles. Volatilomes have received over the last decade increasing attention in ecological, environmental and agricultural studies due to their potential to be used in the biocontrol of plant pathogens and pests and as plant growth-promoting factors. In the present study, we characterised and compared the volatilomes from four different Trichoderma species: T. asperellum B6; T. atroviride P1; T. afroharzianum T22; and T. longibrachiatum MK1. VOCs were collected from each strain grown both on PDA and in soil and analysed using proton transfer reaction quadrupole interface time-of-flight mass spectrometry (PTR-Qi-TOF-MS). Analysis of the detected volatiles highlighted a clear separation of the volatilomes of all the four species grown on PDA whereas the volatilomes of the soil-grown fungi could be only partially separated. Moreover, a limited number of species-specific peaks were found and putatively identified. In particular, each of the four Trichoderma species over-emitted somevolatiles involved in resistance induction, promotion of plant seed germination and seedling development and antimicrobial activity, as 2-pentyl-furan, 6PP, acetophenone and p-cymene by T. asperellum B6, T. atroviride P1, T. afroharzianum T22 and T. longibrachiatum MK1, respectively. Their potential role in interspecific interactions from the perspective of biological control is briefly discussed.
3
Bangerth, Fritz K., Jun Song e Josef Streif. "Physiological Impacts of Fruit Ripening and Storage Conditions on Aroma Volatile Formation in Apple and Strawberry Fruit: A Review". HortScience 47, n.º 1 (janeiro de 2012): 4–10. http://dx.doi.org/10.21273/hortsci.47.1.4.
Resumo:
After a brief description of the “history of research” of aroma volatiles of apple and strawberry fruit, possible reasons for the reduced production of these important quality attributes by particular pre- and postharvest procedures are given. Among the possible physiological factors in association with reduced aroma volatile production, a reduced ethylene sensitivity, a decline in the rate of respiration as well as the content of adenine nucleotides and limited free fatty acids as precursors for aroma volatiles biosynthesis are proposed. A hypothesis about how this sequence of events leads to reduced volatile production is given and finally some suggestions of how to improve volatile synthesis are discussed.
4
Archbold, Douglas D., Ann M. Clements, T. R. Hamilton-Kemp e R. W. Collins. "391 Compression Bruising Alters the Strawberry Volatile Profile". HortScience 34, n.º 3 (junho de 1999): 511C—511. http://dx.doi.org/10.21273/hortsci.34.3.511c.
Resumo:
Prior work indicated that volatile compounds produced by macerated strawberry fruit occurred at levels capable of affecting pathogen development. To determine if a less-severe injury, such as bruising, would alter the volatile profile of strawberry fruit, the headspace volatiles from ripe `Tribute' strawberry fruit were sampled with SPME fiber during the 15 min immediately following and from 75 to 90 min following application of a compression bruise. The compression bruise was applied with a force gauge, and fruit were kept in a closed bottle at room temperature during the study. Of the 14 major volatile products consistently produced by all fruit, acetate esters derived from hexanal, (E)-2-hexenal, and (Z)-3-hexenal increased most, over 50%, in response to bruising during the first interval. During the later interval, bruised fruit produced over 50% more (E)-2-hexenyl acetate and hexyl acetate than control fruit. Most notably, the ratio of levels of (E)-2-hexenyl acetate produced by bruised compared to control fruit were the highest among all 14 major volatiles, over 150% more after 15 min and 270% more at 90 min. Headspace levels of the 6-carbon acetate esters declined for both control and bruised fruit between 15 and 90 min, while levels of the other major volatiles increased. The other 11 volatile compounds were commonly identified aroma volatiles. Headspace levels of some of these were also higher from bruised than control fruit. In particular, headspace levels of ethyl butyrate were increased by bruising 13% after 15 min but over 100% after 90 min, the most of any volatile product other than (E)-2-hexenyl acetate.
5
Mülner, Pascal, Elisa Schwarz, Kristin Dietel, Stefanie Herfort, Jennifer Jähne, Peter Lasch, Tomislav Cernava, Gabriele Berg e Joachim Vater. "Fusaricidins, Polymyxins and Volatiles Produced by Paenibacillus polymyxa Strains DSM 32871 and M1". Pathogens 10, n.º 11 (15 de novembro de 2021): 1485. http://dx.doi.org/10.3390/pathogens10111485.
Resumo:
Paenibacilli are efficient producers of potent agents against bacterial and fungal pathogens, which are of great interest both for therapeutic applications in medicine as well as in agrobiotechnology. Lipopeptides produced by such organisms play a major role in their potential to inactivate pathogens. In this work we investigated two lipopeptide complexes, the fusaricidins and the polymyxins, produced by Paenibacillus polymyxa strains DSM 32871 and M1 by MALDI-TOF mass spectrometry. The fusaricidins show potent antifungal activities and are distinguished by an unusual variability. For strain DSM 32871 we identified numerous yet unknown variants mass spectrometrically. DSM 32871 produces polymyxins of type E (colistins), while M1 forms polymyxins P. For both strains, novel but not yet completely characterized polymyxin species were detected, which possibly are glycosylated. These compounds may be of interest therapeutically, because polymyxins have gained increasing attention as last-resort antibiotics against multiresistant pathogenic Gram-negative bacteria. In addition, the volatilomes of DSM 32781 and M1 were investigated with a GC–MS approach using different cultivation media. Production of volatile organic compounds (VOCs) was strain and medium dependent. In particular, strain M1 manifested as an efficient VOC-producer that exhibited formation of 25 volatiles in total. A characteristic feature of Paenibacilli is the formation of volatile pyrazine derivatives.
6
Cozzolino, Rosaria, Matteo Stocchero, Rosa Perestrelo e José S. Câmara. "Comprehensive Evaluation of the Volatomic Fingerprint of Saffron from Campania towards Its Authenticity and Quality". Foods 11, n.º 3 (27 de janeiro de 2022): 366. http://dx.doi.org/10.3390/foods11030366.
Resumo:
The volatile profiles of eight saffron samples (seven cultivated and one spontaneous) grown in different geographical districts within the Campania region (southern Italy) were compared. Using headspace solid-phase microextraction coupled to gas chromatography–mass spectrometry (HS-SPME/GC-MS), overall, 80 volatiles were identified in the eight landraces. Among them, safranal and its isomers and other related compounds such as isophorones, which are not only key odorants but also pharmacologically active metabolites, have been detected in all the investigated samples. Principal Component Analysis performed on the volatiles’ compounds revealed that the spontaneous sample turned out to be an outlier. In particular, the volatile organic compounds (VOCs) profile of the spontaneous saffron presented four lilac aldehydes and four lilac alcohol isomers, which, to the authors’ knowledge, have never been identified in the volatile signature of this spice. The multivariate statistical analysis allowed the discrimination of the seven cultivate saffron ecotypes in four well-separated clusters according to variety. Moreover, 20 VOCs, able to differentiate the clusters in terms of single volatile metabolite, were discovered. Altogether, these results could contribute to identifying possible volatile signature metabolites (biomarkers) or patterns that discriminate saffron samples grown in Campania region on a molecular basis, encouraging future biodiversity programs to preserve saffron landraces revealing valuable genetic resources.
7
González-Domínguez, Raúl, Ana Sayago, Ikram Akhatou e Ángeles Fernández-Recamales. "Volatile Profiling of Strawberry Fruits Cultivated in a Soilless System to Investigate Cultivar-Dependent Chemical Descriptors". Foods 9, n.º 6 (11 de junho de 2020): 768. http://dx.doi.org/10.3390/foods9060768.
Resumo:
Volatile compounds are essential for food organoleptic characteristics and of great utility for the food industry as potential markers for authenticity purposes (e.g., variety, geographical origin, adulteration). The aim of this study was to determine the characteristic volatile compounds of strawberry samples grown in a soilless system by using headspace solid phase micro-extraction coupled with gas chromatography and to investigate the influence of cultivar (Festival, Candonga, Camarosa) on this volatile profile. We observed that Festival and, to a lesser extent, Candonga varieties were characterized by the richest aroma-related profiles, including higher levels of esters, furanones and terpenes. In particular, methyl butyrate, hexyl hexanoate, linalool, geraniol and furaneol were the most abundant aromatic compounds detected in the three varieties of strawberries. Complementarily, the application of pattern recognition chemometric approaches, including principal component analysis and linear discriminant analysis, demonstrated that concentrations of specific volatiles can be employed as chemical descriptors to discriminate between strawberry cultivars. Accordingly, geraniol and hexyl hexanoate were found to be the most significant volatiles for the discrimination of strawberry varieties.
8
Piette, Anjali A. A., Peter Gao, Kara Brugman, Anat Shahar, Tim Lichtenberg, Francesca Miozzi e Peter Driscoll. "Rocky Planet or Water World? Observability of Low-density Lava World Atmospheres". Astrophysical Journal 954, n.º 1 (21 de agosto de 2023): 29. http://dx.doi.org/10.3847/1538-4357/acdef2.
Resumo:
Abstract Super-Earths span a wide range of bulk densities, indicating a diversity in interior conditions beyond that seen in the solar system. In particular, an emerging population of low-density super-Earths may be explained by volatile-rich interiors. Among these, low-density lava worlds have dayside temperatures that are high enough to evaporate their surfaces, providing a unique opportunity to probe their interior compositions and test for the presence of volatiles. In this work, we investigate the atmospheric observability of low-density lava worlds. We use a radiative-convective model to explore the atmospheric structures and emission spectra of these planets, focusing on three case studies with high observability metrics and substellar temperatures spanning ∼1900–2800 K: HD 86226 c, HD 3167 b, and 55 Cnc e. Given the possibility of mixed volatile and silicate interior compositions for these planets, we consider a range of mixed volatile and rock-vapor atmospheric compositions. This includes a range of volatile fractions and three volatile compositions: water-rich (100% H2O), water with CO2 (80% H2O+20% CO2), and a desiccated O-rich scenario (67% O2+33% CO2). We find that spectral features due to H2O, CO2, SiO, and SiO2 are present in the infrared emission spectra as either emission or absorption features, depending on dayside temperature, volatile fraction, and volatile composition. We further simulate JWST secondary-eclipse observations for each of the three case studies, finding that H2O and/or CO2 could be detected with as few as ∼five eclipses. Detecting volatiles in these atmospheres would provide crucial independent evidence that volatile-rich interiors exist among the super-Earth population.
9
Hussain, Hidayat, Ahmed Al-Harrasi, Ahmed Al-Rawahi e Javid Hussain. "Chemistry and Biology of Essential Oils of GenusBoswellia". Evidence-Based Complementary and Alternative Medicine 2013 (2013): 1–12. http://dx.doi.org/10.1155/2013/140509.
Resumo:
The properties ofBoswelliaplants have been exploited for millennia in the traditional medicines of Africa, China, and especially in the Indian Ayurveda. In Western countries, the advent of synthetic drugs has obscured the pharmaceutical use ofBoswellia, until it was reported that an ethanolic extract exerts anti-inflammatory and antiarthritic effects. Frankincense was commonly used for medicinal purposes. This paper aims to provide an overview of current knowledge of the volatile constituents of frankincense, with explicit consideration concerning the diverseBoswelliaspecies. Altogether, more than 340 volatiles inBoswelliahave been reported in the literature. In particular, a broad diversity has been found in the qualitative and quantitative composition of the volatiles with respect to different varieties ofBoswellia. A detailed discussion of the various biological activities ofBoswelliafrankincense is also presented.
10
Cozzolino, Rosaria, Bernardo Pace, Michela Palumbo, Carmine Laurino, Gianluca Picariello, Francesco Siano, Beatrice De Giulio, Sergio Pelosi e Maria Cefola. "Profiles of Volatile and Phenolic Compounds as Markers of Ripening Stage in Candonga Strawberries". Foods 10, n.º 12 (14 de dezembro de 2021): 3102. http://dx.doi.org/10.3390/foods10123102.
Resumo:
Volatile compounds, quality traits (total phenols and antioxidant capacity) and High-performance liquid chromatography (HPLC)-isolated polyphenols of strawberries, variety Sabrosa, commercially referred to as “Candonga”, harvested at three different times (H1, H2 and H3) and at two different ripening stages, namely half-red (Half-red-H1, Half-red-H2 and Half-red-H3) and red (Red-H1, Red-H2 and Red-H3) were evaluated. Dominant anthocyanins, namely cyanidin-3-O-glucoside, pelargonidin-3-O-glucoside and pelargonidin-3-O-rutinoside, as well as p-coumaryl hexoside increased during harvesting, differently from flavonoids, such as quercetin-3-O-glucoside, kaempferol-3-O-glucoronide and quercetin 3-O-glucoronide, that declined. Samples clustered in different quadrants of the principal component analysis (PCA) performed on volatiles, quality traits and phenolic compounds, highlighting that only the red samples were directly correlated to volatile components, as volatiles clearly increased both in number and amount during ripening. In particular, volatiles with a positive impact on the consumers’ acceptance, including butyl butyrate, ethyl hexanoate, hexyl acetate, nonanal, terpenes and lactones, were positively associated with the Red-H1 and Red-H2 strawberries, while volatiles with negative coefficients related to consumer liking, including isopropyl butyrate, isoamyl butyrate and mesifurane directly correlated with the Red-H3 samples. Accordingly, strawberries harvested at Red-H1 and Red-H2 ripening stages could be preferred by the consumers compared to the Red-H3 fruit. Altogether, these results could help to individuate quality traits as putative markers of the ripening stage, and optimize the process of post-harvesting ripening to preserve or improve the desirable aromatic characteristics of strawberries.
11
Linit, Marc, e W. Terrell Stamps. "Interaction of intrinsic and extrinsic chemical cues in the behaviour of Bursaphelenchus xylophilus (Aphelenchida: Aphelenchoididae) in relation to its beetle vectors". Nematology 3, n.º 4 (2001): 295–301. http://dx.doi.org/10.1163/156854101317020213.
Resumo:
AbstractBursaphelenchus xylophilus, its host trees and beetle vectors represent an unusual ecological system. The fourth stage, dispersal juvenile (JIV) of B. xylophilus is a specialised life stage that must alter its response to a variety of chemical cues over time to properly enter and exit its beetle vector. Neutral storage (NS) lipid content is proposed as a modifier of nematode response to beetleand tree-produced volatiles. The chemotactic response of JIV to a variety of chemicals was tested and the lipid contents of JIV attracted to particular chemicals were quantified. Nematodes with the lowest NS lipid content were attracted to β-myrcene, a pine volatile, while nematodes with the highest NS lipid content were attracted to toluene, a beetle cuticular hydrocarbon. A rolling fulcrum model of the integration of intrinsic (NS lipid) and extrinsic (volatiles) cues is proposed to explain the behavioural ontogeny of JIV in relation to the beetle vector.
12
Negro, Carmine, Rosanna Dimita, Samar Min Allah, Antonio Miceli, Andrea Luvisi, Federica Blando, Luigi De Bellis e Rita Accogli. "Phytochemicals and Volatiles in Developing Pelargonium ‘Endsleigh’ Flowers". Horticulturae 7, n.º 11 (20 de outubro de 2021): 419. http://dx.doi.org/10.3390/horticulturae7110419.
Resumo:
Rose-scented geranium (Pelargonium sp.) have been the subject of many studies concerning essential oil, unlike the edible flowers of scent Pelargonium despite the beneficial properties of chemical compounds present in such organ and the fragrances produced. Therefore, we investigated organic compounds, total phenols and the antioxidant activity of the flowers with particular attention to the volatile compounds emitted by flowers of Pelargonium ‘Endsleigh’ at three stages of development. We identified several major phenols and organic compounds that revealed significative difference compared with other Pelargonium flowers, and employing the solid-phase micro extraction (SPME) methodology we determined that the production of volatile compounds decreases during the flower development. In addition, the emission of volatiles is accomplished mainly by the sepals. In conclusion, to use Pelargonium ‘Endsleigh’ flowers, it is important in ensuring that they have not yet opened and that the sepals are in place.
13
Guo, Yanhong, Tengxun Zhang, Jian Zhong, Tingting Ba, Ting Xu, Qixiang Zhang e Ming Sun. "Identification of the Volatile Compounds and Observation of the Glandular Trichomes in Opisthopappus taihangensis and Four Species of Chrysanthemum". Plants 9, n.º 7 (6 de julho de 2020): 855. http://dx.doi.org/10.3390/plants9070855.
Resumo:
Opisthopappus taihangensis (Ling) Shih, a wild relative germplasm of chrysanthemum, releases a completely different fragrance from chrysanthemum species. We aimed to identify the volatile compounds of the leaves of O. taihangensis and four other Chrysanthemum species using headspace solid-phase micro-extraction combined with gas chromatography-mass spectrometry (HS-SPME-GC/MS). In total, 70 compounds were detected, and terpenoids accounted for the largest percentage in these five species. Many specific compounds were only emitted from O. taihangensis and not from the other four species. In particular, 1,8-cineole could be responsible for the special leaf fragrance of O. taihangensis as it accounted for the largest proportion of the compounds in O. taihangensis but a small or no proportion at all in other species. The glandular trichomes (GTs) in the leaves are the main organs responsible for the emission of volatiles. To explore the relationship between the emissions and the density of the GTs on the leaf epidermis, the shape and density of the GTs were observed and calculated, respectively. The results showed that the trichomes have two shapes in these leaves: T-shaped non-glandular trichomes and capitate trichomes. Histochemical staining analyses indicated that terpenoids are mainly emitted from capitate glandular trichomes. Correlation analysis showed that the volatile amount of terpenoids is highly related to the density of capitate trichomes. In O. taihangensis, the terpenoids content and density of capitate trichomes are the highest. We identified the diversity of leaf volatiles from O. taihangensis and four other Chrysanthemum species and found a possible relationship between the content of volatile compounds and the density of capitate trichomes, which explained the cause of the fragrance of O. taihangensis leaves.
14
Blasi, Francesca, Luna Pollini e Lina Cossignani. "Varietal Authentication of Extra Virgin Olive Oils by Triacylglycerols and Volatiles Analysis". Foods 8, n.º 2 (5 de fevereiro de 2019): 58. http://dx.doi.org/10.3390/foods8020058.
Resumo:
In recent years, there is an increasing interest in high-quality extra virgin olive oils (EVOOs) produced from local cultivars. They have particular chemical/organoleptic characteristics and are frequently subjected to fraud, whereby the control of quality requires a powerful varietal check. In the present research, triacylglycerols (TAGs) and volatiles have been studied as chemical markers for the authentication of EVOO samples from four Italian varieties of Olea europea (Dolce Agogia, Frantoio, Leccino, and Moraiolo). The monocultivar EVOO samples have been subjected to a chemical–enzymatic chromatographic method in order to perform a stereospecific analysis, an important procedure for the characterization of TAG of food products. The results, combined with chemometric analysis (linear discriminant analysis, LDA), were elaborated in order to classify Italian EVOO monocultivar samples. In accordance with the total and intrapositional fatty acid (FA) composition of TAG fraction, the results were allowed to carry out a varietal discrimination. In addition, volatile compounds were also determined by solid-phase micro-extraction gas chromatography-mass spectrometry analysis. All EVOO samples were correctly classified when TAG stereospecific data and volatile results were elaborated by the LDA procedure, even if volatile compounds showed a higher discriminant power.
15
Li, Youli, Xiaobei Han, Si Li, Rongchao Shi, Jiu Xu, Qian Zhao, Tianxiang Liu e Wenzhong Guo. "Improving Tomato Fruit Volatiles through Organic Instead of Inorganic Nutrient Solution by Precision Fertilization". Applied Sciences 14, n.º 11 (27 de maio de 2024): 4584. http://dx.doi.org/10.3390/app14114584.
Resumo:
This study investigated the effects of irrigation with a fully inorganic nutrient solution (control; NNNN) and an organic instead of an inorganic nutrient solution (OIINS) at the flowering–fruit setting (ONNN), fruit expanding (NONN), color turning (NNON), and harvest (NNNO) stages of the first spike on the type and content of tomato fruit volatiles to provide a theoretical basis for tomato aroma improvement and high-quality cultivation. Compared with the control (NNNN), the results showed that all OIINS-related treatments decreased the number of fruit volatiles and increased the relative content of common volatile compounds, characteristic effect compounds, aldehydes, and cis-3-hexenal. In particular, the relative order of performance of the OIINS-related treatments was NNNO > NNON > ONNN > NONN in terms of the relative content of characteristic compounds. For all treatments, the relative cis-3-hexenal and trans-2-hexenal percentages were 20.99–51.49% and 20.22–27.81%, respectively. Moreover, hexanal was only detected in tomato fruits under the NNNN and NNNO treatments. The effects of irrigation with OIINS on tomato fruit volatiles were related to the fruit developmental stage. At the mature stage, the organic nutrient solution was conducive to the accumulation of characteristic compounds and improved the fruit aroma quality.
16
Cao, Yu, Jie Wang, Giacinto Salvatore Germinara, Lijuan Wang, Hong Yang, Yulin Gao e Can Li. "Behavioral Responses of Thrips hawaiiensis (Thysanoptera: Thripidae) to Volatile Compounds Identified from Gardenia jasminoides Ellis (Gentianales: Rubiaceae)". Insects 11, n.º 7 (1 de julho de 2020): 408. http://dx.doi.org/10.3390/insects11070408.
Resumo:
Thrips hawaiiensis is a common thrips pest of various plant flowers with host preference. Plant volatiles provide important information for host-searching in insects. We examined the behavioral responses of T. hawaiiensis adults to the floral volatiles of Gardenia jasminoides Ellis, Gerbera jamesonii Bolus, Paeonia lactiflora Pallas, and Rosa chinensis Jacq. in a Y-tube olfactometer. T. hawaiiensis adults showed significantly different preferences to these four-flower plants, with the ranking of G. jasminoides > G. jamesonii > P. lactiflora ≥ R. chinensis. Further, 29 components were identified in the volatile profiles of G. jasminoides, and (Z)-3-hexenyl tiglate (14.38 %), linalool (27.45 %), and (E3,E7)-4,8,12-trimethyltrideca-1,3,7,11-tetraene (24.67 %) were the most abundant. Six-arm olfactometer bioassays showed that T. hawaiiensis had significant positive responses to (Z)-3-hexenyl tiglate, linalool, and (E3,E7)-4,8,12-trimethyltrideca-1,3,7,11-tetraene tested at various concentrations, with the most attractive ones being 10−3 μL/μL, 10−2 μL/μL and 100 μg/μL for each compound, respectively. In pairing of these three compounds at their optimal concentrations, T. hawaiiensis showed the preference ranking of (Z)-3-hexenyl tiglate > linalool > (E3,E7)-4,8,12-trimethyltrideca-1,3,7,11-tetraene. Large numbers of T. hawaiiensis have been observed on G. jasminoides flowers in the field, which might be caused by the high attraction of this pest to G. jasminoides floral volatiles shown in the present study. Our findings shed light on the olfactory cues routing host plant searching behavior in T. hawaiiensis, providing important information on how T. hawaiiensis targets particular host plants. The high attractiveness of the main compounds (e.g., linalool, (E3,E7)-4,8,12-trimethyltrideca-1,3,7,11-tetraene, particular (Z)-3-hexenyl tiglate) identified from volatiles of G. jasminoides flowers may be exploited further to develop novel monitoring and control tools (e.g., lure and kill strategies) against this flower-inhabiting thrips pest.
17
Xue, Jinjin, Panpan Liu, Junfeng Yin, Weiwei Wang, Jianyong Zhang, Wei Wang, Ting Le, Dejiang Ni e Heyuan Jiang. "Dynamic Changes in Volatile Compounds of Shaken Black Tea during Its Manufacture by GC × GC–TOFMS and Multivariate Data Analysis". Foods 11, n.º 9 (25 de abril de 2022): 1228. http://dx.doi.org/10.3390/foods11091228.
Resumo:
Changes in key odorants of shaken black tea (SBT) during its manufacture were determined using headspace solid-phase microextraction (HS-SPME) combined with comprehensive two-dimensional gas chromatography–time-of-flight mass spectrometry (GC × GC–TOFMS) and multivariate data analysis. A total of 241 volatiles was identified, comprising 49 aldehydes, 40 esters, 29 alcohols, 34 ketones, 30 aromatics, 24 alkenes, 17 alkanes, 13 furans, and 5 other compounds. A total of 27 volatiles had average relative odor activity values (rOAVs) greater than 1, among which (E)-β-ionone, (E,Z)-2,6-nonadienal, and 1-octen-3-one exhibited the highest values. According to the criteria of variable importance in projection (VIP) > 1, p < 0.05, and |log2FC| > 1, 61 discriminatory volatile compounds were screened out, of which 26 substances were shared in the shaking stage (FL vs. S1, S1 vs. S2, S2 vs. S3). The results of the orthogonal partial least squares discriminate analysis (OPLS-DA) differentiated the influence of shaking, fermentation, and drying processes on the formation of volatile compounds in SBT. In particular, (Z)-3-hexenol, (Z)-hexanoic acid, 3-hexenyl ester, (E)-β-farnesene, and indole mainly formed in the shaking stage, which promoted the formation of the floral and fruity flavor of black tea. This study enriches the basic theory of black tea flavor quality and provide the theoretical basis for the further development of aroma quality control.
18
Xue, Jinjin, Panpan Liu, Junfeng Yin, Weiwei Wang, Jianyong Zhang, Wei Wang, Ting Le, Dejiang Ni e Heyuan Jiang. "Dynamic Changes in Volatile Compounds of Shaken Black Tea during Its Manufacture by GC × GC–TOFMS and Multivariate Data Analysis". Foods 11, n.º 9 (25 de abril de 2022): 1228. http://dx.doi.org/10.3390/foods11091228.
Resumo:
Changes in key odorants of shaken black tea (SBT) during its manufacture were determined using headspace solid-phase microextraction (HS-SPME) combined with comprehensive two-dimensional gas chromatography–time-of-flight mass spectrometry (GC × GC–TOFMS) and multivariate data analysis. A total of 241 volatiles was identified, comprising 49 aldehydes, 40 esters, 29 alcohols, 34 ketones, 30 aromatics, 24 alkenes, 17 alkanes, 13 furans, and 5 other compounds. A total of 27 volatiles had average relative odor activity values (rOAVs) greater than 1, among which (E)-β-ionone, (E,Z)-2,6-nonadienal, and 1-octen-3-one exhibited the highest values. According to the criteria of variable importance in projection (VIP) > 1, p < 0.05, and |log2FC| > 1, 61 discriminatory volatile compounds were screened out, of which 26 substances were shared in the shaking stage (FL vs. S1, S1 vs. S2, S2 vs. S3). The results of the orthogonal partial least squares discriminate analysis (OPLS-DA) differentiated the influence of shaking, fermentation, and drying processes on the formation of volatile compounds in SBT. In particular, (Z)-3-hexenol, (Z)-hexanoic acid, 3-hexenyl ester, (E)-β-farnesene, and indole mainly formed in the shaking stage, which promoted the formation of the floral and fruity flavor of black tea. This study enriches the basic theory of black tea flavor quality and provide the theoretical basis for the further development of aroma quality control.
19
Zechman, James M., e John N. Labows Jr. "Volatiles of Pseudomonas aeruginosa and related species by automated headspace concentration – gas chromatography". Canadian Journal of Microbiology 31, n.º 3 (1 de março de 1985): 232–37. http://dx.doi.org/10.1139/m85-045.
Resumo:
The volatile metabolites of three strains of Pseudomonas aeruginosa and one strain each of Pseudomonas cepacia, Pseudomonas maltophilia, Pseudomonas fluorescens, and Pseudomonas putida were analyzed using an automated headspace concentrator incorporating a gas chromatograph. The procedure does not require sample preparation and automates the entire analytical sequence to yield reproducible profiles of volatile constituents. Gas chromatographic profiles of the volatile metabolites of each species were obtained using a 20-min concentration period and two fused silica capillary columns of different polarities. The production of headspace metabolites from trypticase soy broth was studied in relationship to culture incubation time and initial cell concentration. The volatiles identified after 24 h incubation consisted of 1-butanol, isopentanol, toluene, 1-undecene, 2-butanone, 2-heptanone, 2-nonanone, and 2-undecanone. Sufficient amounts of specific metabolites were produced after 5 h incubation to provide information of possible diagnostic value. In particular, all P. aeruginosa strains produced a distinctive series of 1-undecene and methyl ketones after 5 h incubation of media inoculated to provide 2 × 106 cells/mL. The results indicate that when growth and analytical conditions are held constant, P. aeruginosa and related species produce characteristic profiles of headspace metabolites. Since conventional bacteriological tests require 24 h or more for the identification of these pseudomonads, automated volatile analysis could provide an alternative means for the rapid detection of these bacteria.
20
Umar, Akrajas Ali, Muhamad Mat Salleh e Muhammad Yahaya. "Optical Electronic Nose Based on Fe (III) Complex of Porphyrins Films for Detection of Volatile Compounds". Key Engineering Materials 495 (novembro de 2011): 75–78. http://dx.doi.org/10.4028/www.scientific.net/kem.495.75.
Resumo:
Electronic nose is a device that attempts to mimic the living being smell system for detection of particular gases or volatile compounds. This paper reports the development of an optical electronic nose using Fe (III) based metalloporphyrins Langmuir-Blodgett thin films as sensing elements for discriminating four volatiles, 2-propanol, acetone, cyclohexane and ethanol. A multilayer feed forward neural network was developed to classify the input vectors from these two sensors. After the network being trained 100 times and introduced to blind samples, it was found that there are three fault decision for propanol, two for acetone, five for cyclohexane and one four ethanol, during 50 times being recognized to the samples.
21
Bento-Silva, Andreia, Noélia Duarte, Magda Santos, Carina Pedrosa Costa, Maria Carlota Vaz Patto, Sílvia M. Rocha e Maria Rosário Bronze. "Comprehensive Two-Dimensional Gas Chromatography as a Powerful Strategy for the Exploration of Broas Volatile Composition". Molecules 27, n.º 9 (23 de abril de 2022): 2728. http://dx.doi.org/10.3390/molecules27092728.
Resumo:
Broa is a Portuguese maize bread with characteristic sensory attributes that can only be achieved using traditional maize varieties. This study intends to disclose the volatile compounds that are mainly associated with the baking process of broas, which can be important contributors to their aroma. Twelve broas were prepared from twelve maize flours (eleven traditional maize varieties and one commercial hybrid). Their volatile compounds were analyzed by GC×GC–ToFMS (two-dimensional gas chromatography coupled with time-of-flight mass spectrometry) for an untargeted screening of the chemical compounds mainly formed during baking. It was possible to identify 128 volatiles that belonged to the main chemical families formed during this stage. Among these, only 16 had been previously detected in broas. The most abundant were furans, furanones, and pyranones, but the most relevant for the aroma of broas were ascribed to sulfur-containing compounds, in particular dimethyl trisulfide and methanethiol. Pyrazines might contribute negatively to the aroma of broas since they were present in higher amounts in the commercial broa. This work constitutes the most detailed study of the characterization of broas volatile compounds, particularly those formed during the Maillard reaction. These findings may contribute to the characterization of other maize-based foodstuffs, ultimately improving the production of foods with better sensory features.
22
Łyczko, Jacek, Anna Kiełtyka-Dadasiewicz, Hanán Issa-Issa, Mariusz Skrzyński, Renata Galek, Ángel A. Carbonell-Barrachina e Antoni Szumny. "Chemistry behind Quality—Emission of Volatile Enantiomers from Mentha spp. Plant Tissue in Relationship to Odor Sensory Quality". Foods 12, n.º 10 (19 de maio de 2023): 2057. http://dx.doi.org/10.3390/foods12102057.
Resumo:
The quality of food, considering increasing consumer demands and competition among producers, is a highly important issue. Quality concerns are also applicable to the odor quality of herbs and spices (HSs). Meanwhile, HSs commonly are graded based on their essential oils (EOs) content and analysis; but does the instrumental analysis really provide general information about the HSs sensory quality? Three chemotypes of Mentha spp. were used in the present study. From samples diversified by convective drying at different temperatures, EOs were hydrodistillated and analyzed by enantioselective GC-MS; moreover, the source plant material’s volatile profile was analyzed by the HS-SPME technique. The instrumental analysis was confronted with the results of the sensory panel. Changes in enantiomeric composition were observed during the drying process, although no clear correlations or trends could be found for individual chiral components. Furthermore, even with significant differences in particular volatiles’ contribution to plants’ EOs and their volatile profiles, judges were not able to match the sample EOs and plant samples with sufficient effectiveness (~40%). Based on those results, we suggest that volatile enantiomeric distribution does not have an actual influence on odor quality and that the sensory analysis should not be replaced with instrumental analysis, which cannot predict general sensory quality.
23
Robustelli della Cuna, Francesco Saverio, Jacopo Calevo, Elia Bari, Annalisa Giovannini, Cinzia Boselli e Aldo Tava. "Characterization and Antioxidant Activity of Essential Oil of Four Sympatric Orchid Species". Molecules 24, n.º 21 (28 de outubro de 2019): 3878. http://dx.doi.org/10.3390/molecules24213878.
Resumo:
The volatile fractions from fresh inflorescences of naturally growing orchids Anacamptis coriophora (L.) R. M. Bateman, Pridgeon & M. W. Chase subsp. fragrans (Pollini), Anacamptis pyramidalis (L.) R. Ophrys holosericea (Burm.) Greuter and Serapias vomeracea (Burm. f.) B. were isolated by steam distillation and analyzed by GC/FID and GC/MS. Saturated hydrocarbons were quantified as the major constituents of the volatile fraction (47.87–81.57% of the total essential oil), of which long-chain monounsaturated hydrocarbons accounted from 9.20% to 32.04% of the total essential oil. Double bond position in linear alkenes was highlighted by dimethyl disulfide derivatization and MS fragmentation. Aldehydes (from 3.45 to 18.18% of the total essential oil), alcohols (from 0.19% to 13.48%), terpenes (from 0.98 to 2.50%) and acids (0.30 to 2.57%) were also detected. These volatiles compounds may represent a particular feature of these plant species, playing a critical role in the interaction with pollinators. DPPH assay evaluating the antioxidant activity of the essential oils was carried out, showing a dose-dependent antioxidant activity.
24
Wang, Shuai, e Sen Hu. "Hydrogen Isotopic Variations in the Shergottites". Geosciences 10, n.º 4 (17 de abril de 2020): 148. http://dx.doi.org/10.3390/geosciences10040148.
Resumo:
Hydrogen isotopes in the shergottite Martian meteorites are among the most varied in Mars laboratory samples. By collating results of previous studies on major hydroxyl, deuterium, and H2O bearing phases, we provide a compendium of recent measurements in order to elucidate crustal-rock versus mantle-rock processes on Mars. We summarize recent works on volatile and δD measurements in a range of shergottite phases: from melt inclusions, apatite, merrillite, maskelynite, impact melt glass, groundmass glass, and nominal anhydrous minerals. We interpret these observations using an evidence-based approach, considering two particular scenarios: (1) water-rock crustal interactions versus (2) magmatic-based processes. We consider the implications of these measurements and the scope they have for future studies, paying particular attention to future works on H, S, and Cl isotopes in situ, shedding light on the nature of volatiles in the hydrosphere and lithosphere of Mars.
25
Muradova, Mariam, Alena Proskura, Francis Canon, Irina Aleksandrova, Mathieu Schwartz, Jean-Marie Heydel, Denis Baranenko, Liudmila Nadtochii e Fabrice Neiers. "Unlocking Flavor Potential Using Microbial β-Glucosidases in Food Processing". Foods 12, n.º 24 (14 de dezembro de 2023): 4484. http://dx.doi.org/10.3390/foods12244484.
Resumo:
Aroma is among of the most important criteria that indicate the quality of food and beverage products. Aroma compounds can be found as free molecules or glycosides. Notably, a significant portion of aroma precursors accumulates in numerous food products as nonvolatile and flavorless glycoconjugates, termed glycosidic aroma precursors. When subjected to enzymatic hydrolysis, these seemingly inert, nonvolatile glycosides undergo transformation into fragrant volatiles or volatiles that can generate odor-active compounds during food processing. In this context, microbial β-glucosidases play a pivotal role in enhancing or compromising the development of flavors during food and beverage processing. β-glucosidases derived from bacteria and yeast can be utilized to modulate the concentration of particular aroma and taste compounds, such as bitterness, which can be decreased through hydrolysis by glycosidases. Furthermore, oral microbiota can influence flavor perception by releasing volatile compounds that can enhance or alter the perception of food products. In this review, considering the glycosidic flavor precursors present in diverse food and beverage products, we underscore the significance of glycosidases with various origins. Subsequently, we delve into emerging insights regarding the release of aroma within the human oral cavity due to the activity of oral microbial glycosidases.
26
Kröncke, Nina, Sandra Grebenteuch, Claudia Keil, Sebastian Demtröder, Lothar Kroh, Andreas Thünemann, Rainer Benning e Hajo Haase. "Effect of Different Drying Methods on Nutrient Quality of the Yellow Mealworm (Tenebrio molitor L.)". Insects 10, n.º 4 (27 de março de 2019): 84. http://dx.doi.org/10.3390/insects10040084.
Resumo:
Yellow mealworm (Tenebrio molitor L.) represents a sustainable source of proteins and fatty acids for feed and food. Industrial production of mealworms necessitates optimized processing techniques, where drying as the first postharvest procedure is of utmost importance for the quality of the final product. This study examines the nutritional quality of mealworm larvae processed by rack oven drying, vacuum drying or freeze drying, respectively. Proximate composition and fatty acid profile were comparable between the dried larvae. In contrast, larvae color impressions and volatile compound profiles were very much dependent on processing procedure. High-temperature rack oven drying caused pronounced darkening with rather low content of volatiles, pointing toward the progress of Maillard reaction. On the other hand, vacuum drying or freeze drying led to enrichment of volatile Maillard reaction and lipid oxidation intermediates, whose actual sensory relevance needs to be clarified in the future. Beyond sensory and visual importance drying intermediates have to be considered with regard to their metal ion chelating ability; in particular for essential trace elements such as Zn2+. This study found comparable total zinc contents for the differently dried mealworm samples. However, dried larvae, in particular after rack oven drying, had only low zinc accessibility, which was between 20% and 40%. Therefore, bioaccessibility rather than total zinc has to be considered when their contribution to meeting the nutritional requirements for zinc in humans and animals is evaluated.
27
Robustelli della Cuna, Francesco Saverio, Cinzia Boselli, Adele Papetti, Barbara Mannucci, Jacopo Calevo e Aldo Tava. "Composition of Volatile Fraction from Inflorescences and Leaves of Dendrobium moschatum (Orchidaceae)". Natural Product Communications 13, n.º 1 (janeiro de 2018): 1934578X1801300. http://dx.doi.org/10.1177/1934578x1801300127.
Resumo:
The volatile fractions from fresh inflorescences and leaves of Dendrobium moschatum (Buchanan-Hamilton) Swartz (Orchidaceae) were isolated by steam distillation with a yield of 0.498% and 0.041% (weight/fresh weight basis), respectively. From GC/FID and GC/MS analyses, coumarin was identified to be the most abundant constituent and quantified as 48.8% and 47.8% of the total volatiles from inflorescences and leaves, respectively. Hydrocarbons, ketones, esters, acids and aldehydes were also detected. Long chain mono unsaturated hydrocarbons were quantified in higher amount in leaves and their structures were elucidated by GC/MS of their dimethyl disulfide derivatives. These compounds together with long chain ethyl esters and methyl ketones may represent a particular feature of this plant species and can play a critical role in the interaction with pollinator insect.
28
Bertamini, Massimo, Maria Stella Grando, Pietro Zocca, Michele Pedrotti, Silvia Lorenzi e Luca Cappellin. "Linking monoterpenes and abiotic stress resistance in grapevines". BIO Web of Conferences 13 (2019): 01003. http://dx.doi.org/10.1051/bioconf/20191301003.
Resumo:
Rising temperatures and ozone levels are among the most striking stressful phenomena of global climate changes, and they threaten plants that are unable to react rapidly and efficiently. Generic responses of plants to stresses include the production of excess reactive oxygen species (ROS). Excessive ROS accumulation can lead to extensive oxidation of important components such as nucleic acids, proteins and lipids which can further exacerbate ROS accumulation leading to programmed cell death. Although most studies on plant antioxidants have focused on non-volatile compounds, volatiles belonging to the isoprenoid family have been implicated in the protection against abiotic stresses, in particular thermal and oxidative stress whose frequency and extent is being exacerbated by ongoing global change and anthropogenic pollution. Historically, research has focused on isoprene, demonstrating that isoprene-emitting plants are more tolerant to ozone exposure and heat stress, reducing ROS accumulation. Yet, evidence is being compiled that shows other volatile isoprenoids may be involved in plant responses against abiotic stresses. Grapevines are not isoprene emitters but some varieties produce other volatile isoprenoids such as monoterpenes. We investigated photosynthesis and emission of volatile organic compounds upon heat stress in two Vitis vinifera cv. ‘Chardonnay’ clones differing only for a mutation in the DXS gene (2-C-methyl-D-erythritol 4-phosphate (MEP) pathway), regulating volatile isoprenoid biosynthesis. We showed that the mutation led to a strong increase in monoterpene emission upon heat stress. At the same time, maximum photochemical quantum yield (Fv/Fm ratio) of PSII was affected by the stress in the non-emitting clone while the monoterpene emitter showed a significant resilience, thus indicating a possible antioxidant role of monoterpenes in grapevine. Future mechanistic studies should focus on unveiling the actual mechanism responsible for such findings.
29
Blake, D., A. L. Hinwood e P. Horwitz. "Peat fires and air quality: Volatile organic compounds and particulates". Chemosphere 76, n.º 3 (julho de 2009): 419–23. http://dx.doi.org/10.1016/j.chemosphere.2009.03.047.
30
Sawoszczuk, Tomasz, Justyna Syguła-Cholewińska e Julio M. del Hoyo-Meléndez. "The detection of active moulds on historical silk by the means of the headspace–solid phase micro-extraction–gas chromatography–mass spectrometry method". Textile Research Journal 88, n.º 9 (17 de fevereiro de 2017): 1013–25. http://dx.doi.org/10.1177/0040517517693984.
Resumo:
The goal of this work was to analyze the profile of microbial volatile organic compounds (MVOCs) emitted by moulds growing on silk samples in search of particular volatiles mentioned in the literature as indicators of active mould growth. The selected moulds were inoculated on three types of media: (1) samples of pure silk placed on microbial media, (2) samples of historical silk placed on microbial media, and (3) agar containing amino acids that are elements of the structure of fibroin. All samples were prepared inside vials (closed system). In the first and second cases the media did not contain any sources of organic carbon, nitrogen, or sulfur—the silk was the only nutrient for the moulds. A fourth type of sample was historical silk prepared in a Petri dish without a microbial medium and inoculated with a fibroinolytically active mould (open system). The MVOCs emitted by moulds were sampled with the headspace–solid phase micro-extraction method. Volatiles extracted on Divinylbenzene/Carboxen/Polydimethylsiloxane (DVB/CAR/PDMS) fibers were analyzed in a gas chromatography–mass spectrometry system. Qualitative and quantitative analyses of chromatograms were carried out in search of indicators of metabolic activity. The results showed that there are three groups of volatiles that can be used for the detection of active forms of moulds on silk. Thus, this can be a valuable tool for the fast detection of mould activity on historical silk objects. To the best of our knowledge, this is the first work to measure MVOCs emitted by moulds growing on silk.
31
Coletta, Antonio, Aline Theodoro Toci, Sandra Pati, Giuseppe Ferrara, Francesco Grieco, Maria Tufariello e Pasquale Crupi. "Effect of Soil Management and Training System on Negroamaro Wine Aroma". Foods 10, n.º 2 (19 de fevereiro de 2021): 454. http://dx.doi.org/10.3390/foods10020454.
Resumo:
This study aimed to assess the impact of two soil managements and training systems on yield and wine aroma compounds of Negroamaro variety grown in a warm climate region (southern Italy). Cover crop (CC) and soil tillage (ST) as soil management, whilst bilateral Guyot (BG) and monolateral Guyot (MG) as training systems were compared. Free and bound volatile fractions were evaluated by GC-MS. ST and CC as well as BG and MG significantly affected yield parameters. In particular, yield was higher in ST and BG than in CC and MG, respectively; moreover, it was found to be positively influenced by interaction between BG and ST. Regarding aroma compounds, significant interactions between soil management and training system factors were observed. In case of free volatiles, the most positive interaction was found between BG and ST, whereas, for bound volatiles, the best interaction was represented by MG with both soil tillage and cover crop. Vine leaf area and development over vine growth stages along with water stress levels played an important role in determining the aroma profile as well as yield parameters. In conclusion, the training system significantly interacted with soil management and affected most of important aroma compounds in Negroamaro wine.
32
Ramya, Mummadireddy, Seonghoe Jang, Hye-Ryun An, Su-Young Lee, Pil-Man Park e Pue Hee Park. "Volatile Organic Compounds from Orchids: From Synthesis and Function to Gene Regulation". International Journal of Molecular Sciences 21, n.º 3 (10 de fevereiro de 2020): 1160. http://dx.doi.org/10.3390/ijms21031160.
Resumo:
Orchids are one of the most significant plants that have ecologically adapted to every habitat on earth. Orchids show a high level of variation in their floral morphologies, which makes them popular as ornamental plants in the global market. Floral scent and color are key traits for many floricultural crops. Volatile organic compounds (VOCs) play vital roles in pollinator attraction, defense, and interaction with the environment. Recent progress in omics technology has led to the isolation of genes encoding candidate enzymes responsible for the biosynthesis and regulatory circuits of plant VOCs. Uncovering the biosynthetic pathways and regulatory mechanisms underlying the production of floral scents is necessary not only for a better understanding of the function of relevant genes but also for the generation of new cultivars with desirable traits through molecular breeding approaches. However, little is known about the pathways responsible for floral scents in orchids because of their long life cycle as well as the complex and large genome; only partial terpenoid pathways have been reported in orchids. Here, we review the biosynthesis and regulation of floral volatile compounds in orchids. In particular, we focused on the genes responsible for volatile compounds in various tissues and developmental stages in Cymbidium orchids. We also described the emission of orchid floral volatiles and their function in pollination ecology. Taken together, this review will provide a broad scope for the study of orchid floral scents.
33
Königsberger, Erich, Sebastian Bochmann, Peter M. May e Glenn Hefter. "Thermodynamics of impurities in hydrometallurgical processes". Pure and Applied Chemistry 83, n.º 5 (7 de abril de 2011): 1075–84. http://dx.doi.org/10.1351/pac-con-11-02-07.
Resumo:
Impurities in hydrometallurgical process liquors frequently impact on product quality and yield, change physicochemical properties of the liquor, and form hard scale on heat exchangers and condensers. Organic compounds are of particular concern especially in the Bayer process, where impurities build up in the recycled liquor if not controlled. Depending on the redox state of the liquor, such compounds can undergo a variety of complex chemical reactions, including the formation of volatiles that can potentially cause environmental, health, and safety concerns. To aid in the development of appropriate control strategies, robust thermodynamic models for multicomponent aqueous systems containing large numbers of electrolytes and nonelectrolytes are required. Applications of thermodynamic models are discussed that range from the partitioning of volatile compounds in flash trains to the prediction of mixing properties of organic impurities with major Bayer liquor components.
34
Özdemir, Nilgün, Ömer Şimşek, Hasan Temiz e Ahmet Hilmi Çon. "The effect of fermentation time on the volatile aromatic profile of tarhana dough". Food Science and Technology International 25, n.º 3 (3 de dezembro de 2018): 212–22. http://dx.doi.org/10.1177/1082013218815325.
Resumo:
Tarhana is a traditional food produced by fermentation of a dough prepared by mixing wheat flour, yoghurt, tomato, paprika, onion and mint. The fermentation of mixture of natural products gives the tarhana an aromatized desired food characteristic. Therefore, we aimed to determine the effects of fermentation time at home and commercial scale on the aromatic volatile profile of tarhana. In this respect, nine different tarhana dough samples were prepared at home and commercial scale and analysed for volatile and organic acid composition during fermentation which were then evaluated by principal component analysis. In all dough samples, the lactic, succinic and acetic acids were the most produced organic acids while the amounts of ketones decreased, and the alcohols, in particular the esters, increased within fermentation. Particularly, ethyl-lactate and ethyl-acetate increased significantly as well as ethyl-caprylate, ethyl-capronate and ethyl-hexanote responsible for fruity and flower flavour were also accumulated. Tarhana doughs were clustered in two main groups after five days of fermentation with principal component analysis and these clusters remained stable until the end of fermentation. As a conclusion, fermentation time determines the desirable tarhana by ensuring the formation of aromatic volatiles particularly esters. It is necessary to ferment tarhana for at least five days in order to obtain typical aromatic properties.
35
Li, Jufen, Tao Lin, Dandan Ren, Tan Wang, Ying Tang, Yiwen Wang, Ling Xu, Pinkuan Zhu e Guobin Ma. "Transcriptomic and Metabolomic Studies Reveal Mechanisms of Effects of CPPU-Mediated Fruit-Setting on Attenuating Volatile Attributes of Melon Fruit". Agronomy 11, n.º 5 (19 de maio de 2021): 1007. http://dx.doi.org/10.3390/agronomy11051007.
Resumo:
N1-(2-chloro-4-pyridyl)-N3-phenylurea (CPPU), a synthetic cytokinin-active compound, is widely applied to induce parthenocarpic fruit set and enhance melon fruit enlargement (Cucumis melo L.). CPPU may also influence fruit quality; however, the mechanisms through which this occurs remain unknown. We investigated the differences in volatile emissions between parthenocarpic fruit set by CPPU (C) and seeded fruit set by artificial pollination (P). Gas chromatography–mass spectrometry (GC–MS) analysis revealed that six volatile organic compounds (VOCs) emitted by the P-group fruits were not detected in C-group fruits. The relative abundances of another 14 VOCs emitted by the CPPU-treated fruits were less than those in the P-group fruits. RNA sequencing analysis indicated that a total of 1027, 994, and 743 differentially expressed genes (DEGs) were detected in the C20 (treatment with 20 mg·L–1 CPPU) vs. P, P-C20 (pollination followed by 20 mg·L−1 CPPU treatment) vs. P, and P-C20 vs. C20 treatments, respectively. Compared with the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases, the DEGs related to fatty acid degradation and metabolism, which contribute to volatile production, were enriched. In particular, DEGs such as carotenoid cleavage dioxygenase (CCD)-, lipoxygenase (LOX)-, alcohol dehydrogenase (ADH)-, and alcohol acyltransferase (ATT)-related genes were closely related to the formation of volatiles. In summary, our study provides a metabolic and transcriptomic atlas, reveals the impact of CPPU on VOCs, and enhances our understanding of the mechanisms of CPPU that contribute towards generally reducing the quality of melon fruit.
36
Breuer, Doris. "Early planetary atmospheres and surfaces: Origin of the Earth’s water, crust and atmosphere". Proceedings of the International Astronomical Union 14, S345 (agosto de 2018): 156–63. http://dx.doi.org/10.1017/s1743921319001807.
Resumo:
AbstractThe origin of the planets atmosphere is a profound question of comparative planetology. There are two competing models, i.e. outgassing from the interior or late delivery from comets or volatiles-rich asteroids after most of the planet has been formed, of which the former is currently preferred. Meteorite compositions as well as radial mixing during accretion derived from accretion models suggest that the building blocks of the terrestrial planets contained some volatiles. Processes like dehydration by hydrous melting, oxidation, impact devolatilization, and in particular degassing during magma ocean solidification will then lead to a significant volatile loss of the interior and to the formation of a dense atmosphere during the early stages of planetary evolution. These processes are also responsible for the oxidation state of this early atmosphere, i.e. whether it was more reduced or oxidized. Although this early volatile loss was very efficient, the interior probably retained some water. This was distributed in the subsequent evolution between interior and atmosphere, as well as on the surface as liquid water in case of favorable temperature and pressure conditions. The main processes responsible for the water distribution are volcanic outgassing driven by partial melting of the silicate mantle and formation of the crust and recycling of water-rich crustal material. Here, an important difference between the terrestrial planets is the tectonic style prevailing on the planet. For the Earth with its plate tectonics, recycling of water is very efficient and can even balance the outgassing. For terrestrial planets in the stagnant lid regime of mantle convection such as Mars, the exchange of water between the interior and the surface/atmosphere is mainly in one direction and results in a continuous depletion of the interior. In this talk, I will briefly review our current knowledge on these interactions between interior and atmosphere and on the problem we are facing to better understand the influence of the interior on the habitability of a planet.
37
Mucignat-Caretta, Carla, e Antonio Caretta. "CHEMICAL SIGNALS IN MALE HOUSE MICE URINE: PROTEIN-BOUND MOLECULES MODULATE INTERACTIONS BETWEEN SEXES". Behaviour 136, n.º 3 (1999): 331–43. http://dx.doi.org/10.1163/156853999501351.
Resumo:
AbstractThe role of urinary chemosignals in sexual interactions was investigated in pairs of adult mice. Based on previous findings, volatile molecules bound by the Major Urinary Proteins (MUPs) from adult male urine were thought to be sufficient to carry information about the sex of the emitter, and thus sufficient to modify the behaviour of conspecifics. In the first experiment, virgin and stud adult males were exposed to receptive females painted or not with MUPs-borne molecules. Both virgin and stud males showed an increased latency to the first anogenital sniff and a reduced number of sniffings towards MUPs-treated females. This suggests that adult mice are repelled by MUPs-borne volatile molecules, even in the presence of female stimuli conveyed by receptive mates. In the second experiment only stud males were tested, with ovariectomized or estrogen-primed females. These latter were either untreated, painted with MUPs-borne molecules or MUPs without volatile ligands. Ovariectomized females and those treated with MUPs without ligands received less sniffs than the other two groups. Estrogen-primed females were mounted more times, with a shorter latency. Ovariectomized females and females treated with MUPs-borne ligands were attacked earlier by males. The presence of chemical cues from male urine is thus sufficient to modify the behaviour of stud males towards receptive females. In particular, MUPs-borne volatiles are sufficient to act as male cues and to induce aggression towards receptive females. It can be speculated that in nature adult male mice rely on olfactory cues like MUPs-borne odorants to firstly identify a male conspecific and possibly use similar chemical cues from their own urine to signal their presence.
38
Schulz, Hans, Gilberto Bandeira De Melo e Farid Ousmanov. "Volatile organic compounds and particulates as components of diesel engine exhaust gas". Combustion and Flame 118, n.º 1-2 (julho de 1999): 179–90. http://dx.doi.org/10.1016/s0010-2180(98)00146-1.
39
Kacergis, Julie B., Robert B. Jones, Carolyn K. Reeb, William A. Turner, John L. Ohman, Margarett R. Ardman e Beverly Paigen. "Air Quality in an Animal Facility: Particulates, Ammonia, and Volatile Organic Compounds". American Industrial Hygiene Association Journal 57, n.º 7 (julho de 1996): 634–40. http://dx.doi.org/10.1080/15428119691014693.
40
Ciganek, M., e J. Neca. "Chemical characterization of volatile organic compounds on animal farms". Veterinární Medicína 53, No. 12 (29 de dezembro de 2008): 641–51. http://dx.doi.org/10.17221/1969-vetmed.
Resumo:
More than one hundred volatile organic substances were identified by gas chromatography and mass spectrometry (GC/MS) in the indoor and outdoor air, stable and farm road dust and farm soil samples from two pig and cattle farms in the South Moravian Region. Volatile fatty acids (acetic, propanoic, butanoic and pentanoic acids) and their esters dominated along with aldehydes (butanal, pentanal and hexanal) and 4-methylphenol in the indoor and outdoor air samples. Road dust and soil samples contained mainly volatile aromatic compounds (toluene, benzene, ethylbenzene, styrene and xylenes), aliphatic hydrocarbons (largely n-alkanes), dichloromethane and carbon disulphide. The health risks associated with particular volatile compounds detected in the indoor and outdoor samples from the farms need to be assessed.
41
Leigh, Victoria, e Sarah MacLean. "Silent deaths: a commentary on new mortality data relating to volatile substance abuse in Great Britain". Drugs and Alcohol Today 19, n.º 2 (3 de junho de 2019): 86–96. http://dx.doi.org/10.1108/dat-08-2018-0039.
Resumo:
Purpose The purpose of this paper is to provide a commentary on new information from the Office for National Statistics (ONS) on deaths caused by volatile substance abuse (VSA) in Great Britain which occurred between 2001 and 2016. Design/methodology/approach Comparing the new study with previous mortality data, the authors consider the strengths and some limitations of the analysis provided by ONS. Findings By utilising a broader range of codes and collating additional information from death certificates, the new report provides a more comprehensive measure of VSA mortality than was previously available, showing increasing prevalence of deaths. The age profile of people dying is older than in previous studies. Most deaths were associated with inhalation of gases and almost three-quarters of deaths involved volatile substances alone. Practical implications Understanding VSA mortality is essential for service planning. It is important that we identify why so many people whose deaths are associated with VSA are not accessing treatment, with particular concern about treatment access for those who only use volatiles. Training to support drug and alcohol and other health service staff to respond to VSA is essential. In future reports, data to identify socioeconomic correlations of VSA deaths would enable targeted responses. Additionally, information on whether deaths occur in long term rather than episodic or one-off users could enable risk reduction education. Originality/value This paper shows how data on VSA deaths may inform for policy and service planning.
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Najar, Basma, Sonia Demasi, Matteo Caser, Walter Gaino, Pier Luigi Cioni, Luisa Pistelli e Valentina Scariot. "Cultivation Substrate Composition Influences Morphology, Volatilome and Essential Oil of Lavandula Angustifolia Mill." Agronomy 9, n.º 8 (26 de julho de 2019): 411. http://dx.doi.org/10.3390/agronomy9080411.
Resumo:
Aromatic plants are commonly produced for ornamental, cosmetic and medicinal purposes. Their morphological traits and the amounts and compositions of the volatile substances and essential oils (EOs) produced can be influenced by several factors, including the cultivation technique. In the present study, the influence of substrate composition on Lavandula angustifolia Mill. production was evaluated. In particular, substrates containing mixes of peat (P), green compost (C) and/or demolition aggregates (A) were tested in the following ratios: 70%:30% v/v, P:C; 70%:30% v/v, P:A; and 40%:30%:30% v/v, P:C:A. The P:C mixture allowed to obtain the best results in terms of survival rate, compactness of the plant and flower production. The P:C:A led to higher yields and better quality of EOs, with higher amounts of linalool, an important compound for medicinal uses. The volatiles and the blooming trend were not affected by the different cultivation substrates. Therefore, substrate composition in pot lavender cultivation can be regulated depending on the final use of the plant, successfully using locally sourced material in addition to peat.
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Stevenson, R. J., X. D. Chen e O. E. Mills. "Modern analyses and binding studies of flavour volatiles with particular reference to dairy protein products". Food Research International 29, n.º 3-4 (abril de 1996): 265–90. http://dx.doi.org/10.1016/0963-9969(96)00028-2.
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Simon, Timothy R., e Fu Zhao. "Chemical characterization of particulates and volatile organic compounds emitted during fused deposition modeling". Manufacturing Letters 35 (agosto de 2023): 1284–92. http://dx.doi.org/10.1016/j.mfglet.2023.07.003.
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Van Ba, Hoa, Kyeong Seon Ryu, Nguyen Thi Kim Lan e Inho Hwang. "Influence of particular breed on meat quality parameters, sensory characteristics, and volatile components". Food Science and Biotechnology 22, n.º 3 (junho de 2013): 651–58. http://dx.doi.org/10.1007/s10068-013-0127-4.
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Staszewska, Ewelina, e Małgorzata Pawłowska. "Control of Landfill Gases Emission with Particular Emphasis on Btex". Ecological Chemistry and Engineering S 19, n.º 2 (1 de janeiro de 2012): 239–48. http://dx.doi.org/10.2478/v10216-011-0018-7.
Resumo:
Control of Landfill Gases Emission with Particular Emphasis on BtexLandfilling is the most popular way for waste disposal and has been widely applied globally. A large quantity of volatile organic compounds (VOCs) is released from landfills. Among them, BTEX (benzene, toluene ethylbenzene and xylene) is a major group of pollutants, which have now become a cause for concern worldwide because of their toxic properties. For this reason, strict regulations have come into force which induce researchers to find methods to reduce their emissions. This article contains descriptions of several aerobic metabolic pathways for the degradation of BTEX, which are provided by two enzymatic systems (dioxygenases and monooxygenases). Special attention was paid to biofiltration - a method for improving the efficiency of treatment of BTEX released from landfills.
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Pestoni, B., K. Altwegg, H. Balsiger, N. Hänni, M. Rubin, I. Schroeder, M. Schuhmann e S. Wampfler. "Detection of volatiles undergoing sublimation from 67P/Churyumov-Gerasimenko coma particles using ROSINA/COPS". Astronomy & Astrophysics 651 (julho de 2021): A26. http://dx.doi.org/10.1051/0004-6361/202140634.
Resumo:
Context. In an earlier study, we reported that the ram gauge of the COmet Pressure Sensor (COPS), one of the three instruments of the Rosetta Orbiter Spectrometer for Ion and Neutral Analysis (ROSINA), could be used to obtain information about the sublimating content of icy particles, made up of volatiles and conceivably refractories coming from comet 67P/Churyumov-Gerasimenko. Aims. In this work, we extend the investigation to the second COPS gauge, the nude gauge. In particular, we analyse the volume of the volatile content of coma particles, along with a search for possible dependencies between the nude gauge detection rate (i.e. the rate at which icy particles are detected by the nude gauge) and the position of the Rosetta spacecraft. We also investigate the correlations of the nude gauge detection rate with the quantities associated with cometary activity. Methods. We inspected the density measurements made by the nude gauge for features attributable to the presence of icy particles inside the instrument. These data were then analysed statistically based on the amplitude of the feature and on the position of the spacecraft at the time of detection. Results. Although it was not originally designed for such a purpose, the COPS nude gauge has been able to detect ~67 000 features generated by the sublimation of the volatile content of icy particles. The nude gauge detection rate follows a trend that is inversely proportional to the heliocentric distance. This result is interpreted as a confirmation of a possible relation between the nude gauge detection rate and cometary activity. Thus, we compared the former with parameters related to cometary activity and obtained significant correlations, indicating that the frequency of icy particle detection is driven by cometary activity. Furthermore, by representing the volatile part of the icy particles as equivalent spheres with a density of 1 g cm−3, we obtained a range of diameters between 60 and 793 nm, with the smaller ones (<390 nm in diameter) having a size distribution power index of −4.79 ± 0.26.
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Wang, Shuzhen, Jinying Wang, Guoxin Dong, Xia Chen, Shulin Wang, Feng Lei, Xuebing Su e Qin Bai. "Effect of Different Extraction Methods on Quality Characteristics of Rapeseed and Flaxseed Oils". Journal of Food Quality 2022 (19 de setembro de 2022): 1–12. http://dx.doi.org/10.1155/2022/8296212.
Resumo:
This study reports the effect of roasted pretreatment combined with screw press, hydraulic press, and Soxhlet extraction methods on various quality indexes of rapeseed and flaxseed oils, including the oil yield, sensory indexes (color, smell, clarity, viscosity, and colligation score), physicochemical properties (acid value, peroxide value, saponification value, moisture and volatiles), major components (fatty acid composition and triglyceride composition), and minor components (volatile compounds, total phenols, and vitamin E contents). The results indicated that the oil yield, sensory indexes, physicochemical properties, fatty acid composition, volatile compounds, total phenol, and vitamin E contents in vegetable oils have been significantly affected by different extraction methods. The yields of rapeseed and flaxseed oils of Soxhlet extraction method were increased by 30.10%–73.90% and 6.30%–54.40%, respectively, compared with other treatment groups. In addition, roasted pretreatment significantly increased the yields of oils by 4.10%–25.00% and 6.70%–23.15%, respectively, compared with the untreated group. The contents of linolenic acid and vitamin E in rapeseed and flaxseed oils extracted from screw press method were higher. In particular, the linolenic acid content of cold-pressed rapeseed oil extracted by screw press increased by 1.50%–23.80% compared with other treatment groups. In addition, the contents of vitamin E in cold-pressed rapeseed oil and flaxseed oil obtained by screw press increased by 1.22%–78.91% and 3.00%–18.80%, respectively. The Soxhlet extraction could improve oil yield and total phenol content, but the quality of the oil was inferior due to high acid values (0.93–3.36 mg KOH/g) and peroxide values (0.70–5.23 meq O2/kg). Furthermore, the hydraulic press method could extract vegetable oils with excellent sensory scores. The roasted pretreatment gives the rapeseed and flaxseed oils a good smell. The major volatile compounds in rapeseed and flaxseed oils were aldehydes, acids, alcohols, heterocycles, and ketones. Different extraction methods and pretreatment had no significant effect on the compositions and contents of triglycerides. This study provides a basic understanding on the selection of appropriate oil extraction techniques for oil extraction at a large scale.
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Hosseini, Seyed Ali, Seyed Hossein Goldansaz, Astrid T. Groot, Steph B. J. Menken, Frans Van Der Wielen, Cedric Wissel, Joeri Vercammen, Eva De Rijke e Peter Roessingh. "Identification of Bioactive Plant Volatiles for the Carob Moth by Means of GC-EAD and GC-Orbitrap MS". Applied Sciences 11, n.º 18 (16 de setembro de 2021): 8603. http://dx.doi.org/10.3390/app11188603.
Resumo:
The aim of this study was to validate a workflow that allows structural identification of plant volatiles that induce a behavioral response in insects. Due to the complexity of plant volatile emissions and the low levels at which these bioactive components tend to occur, gas chromatography-electroantennography (GC-EAD) was applied as the prime differentiator technique, i.e., to indicate particular peaks of interest in the chromatogram. In a next step, the analysis was repeated under identical conditions using GC-Orbitrap mass spectrometry (MS). Combining electron impact (EI) ionization and chemical ionization (CI) with the superior spectral resolution and mass accuracy of the technique enabled straightforward identification of these unknowns, with high confidence in a minute amount of time. Moreover, because of the intrinsic sensitivity of the technique, components that occur at trace amounts but may induce disproportional large behavioral responses are evenly well-identified. We were able to positively identify β-caryophyllene as a bioactive compound in female carob moths. Behavioral attraction was negatively correlated with the amount of β-caryophyllene in host fruits. In an oviposition experiment on filter paper, β-caryophyllene was stimulated in the range of 40–100 ng, while concentrations above 200 ng inhibited oviposition.
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Dimita, Rosanna, Samar Min Allah, Andrea Luvisi, Davide Greco, Luigi De Bellis, Rita Accogli, Carlo Mininni e Carmine Negro. "Volatile Compounds and Total Phenolic Content of Perilla frutescens at Microgreens and Mature Stages". Horticulturae 8, n.º 1 (12 de janeiro de 2022): 71. http://dx.doi.org/10.3390/horticulturae8010071.
Resumo:
Microgreens are considered products of high biological value because they contain natural and beneficial metabolites and antioxidants in high amounts; also, consumers appreciate them very much for their aromas. In this work, we focused our attention on the volatile organic compounds (VOCs) emitted from whole fresh leaves of two Chinese basil varieties (Perilla frutescens var. frutescens and var. crispa) at the microgreens stage; to show that the emission is microgreens specific we tested whether this capacity remains during subsequent growth of the plants. We found differences between the VOCs produced by the leaves of the two varieties at the microgreens stage and significantly reduced emission after development (additional four weeks of growth) particularly for the green variety (var. frutescens). The main volatiles emitted by whole leaves were D-Limonene for the red variety (crispa) and 2-Hexanoylfuran for the green one. In addition, the total phenolic content (TPC) and antioxidant power increase in adult leaves. These results clearly indicate that the particular smell of microgreens Perilla leaves depends on the specific variety and is not related to the amount of total phenols or antioxidant capacity of the leaves.