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Volatile constituents in mango ‘Ataulfo’ (Mangifera indica L.) fruit were isolated by HS–SPME and solvent-assisted flavor evaporation (SAFE). Analyses were performed by GC–FID, GC–MS and GC–O. Aroma extract dilution analysis (AEDA) and odor activity value (OAV) were applied to find the odor-active compounds. A total of 108 volatile compounds comprising > 99% of the SAFE extract were identified. Major compounds were δ-3-carene, terpinolene, α-pinene, limonene and myrcene. The application of the AEDA and OAV strategies afforded 28 odor-active compounds. For the first time, hexan-1-ol, heptan-1-ol, β-pinene, α-phellandrene, γ-terpinene, dodecanal and α-humulene are described as important contributors to mango aroma.

In the present work, the footprint of carbonyl compounds in hand scent was achieved by a miniaturized method consisting of sampling with cotton gauze, extraction and derivatization using 2,4-dinitrophenylhydrazine (DNPH) and preconcentration, separation and detection by in-tube solid-phase microextraction (IT-SPME) coupled to nano-liquid chromatography/Uv–vis diode array detection. The coupling IT-SPME-nanoLC-DAD was solved by using a two-valve system: the first valve for loading the sample and the second one to perform IT-SPME. To this aim, a nanoparticle-based capillary column was employed. Firstly, the transfer time from the load loop to the NP-based capillary column in the IT-SPME system was optimized. Additionally, the conditioning and clean-up steps were also studied. For the chromatographic separation of DNPH derivatives, gradient elution mode (acetonitrile/water) and a C18 nanocolumn were employed. The detection limits achieved were between 0.5 and 1.5 μg/L and % rsd was lower than 5% for quantification limits. The proposed methodology gave rise to different chromatographic profiles of carbonyl compounds in the hand scent of several volunteers. These profiles were obtained by estimating the relative peak area of selected carbonyls in hand scent. Nonanal, decanal and dodecanal and other low polarity carbonyl compounds (unknown hydrazones) were detected in the odor profiles.

Purpose Silicon (Si) plays beneficial role in alleviating biotic and abiotic stresses but comparative investigations with Si nanoparticles (Si-NPs) under water restriction on medicinal plants is not recognized. The aim of this study was to observe the Si and Si-NPs effects on growth, physio-chemical attributes, and essential oil (EO) profile in aerial parts of coriander (coriandrum sativum L.) under water stress. Methods A split-plot experiment was conducted with irrigation regimes (irrigation after 60, 90, and 120 mm evaporation from Class A pan) in the main plots and foliar application of Si (in the form of Na2SiO3) and Si-NPs in the subplots during 2019 and 2020. Results The results represented drought particularly severe stress decreased biological yield and relative water content (RWC) but increased total soluble sugar (TSS). Both Si and Si-NPs improved plant growth and yield through improved RWC, TSS, total phenolic content (TPC) and total flavonoid content (TFC). Moderate drought stress with Si-NPs was highly effective on TPC, TFC, EO percentage and yield. The main EO constitutes were n-Decanal (20.8-27.6%), 2E-Dodecanal (13.3-16.7%), 2E-Decanal (13.9-18.7%), 2E-Tridecen-1-al (7.3-10.5%), Dodecanal (7.2-10.6%), and n-Nonane (4.3-8.7%). Heat map analysis (HMA) showed foliar application of Si and Si-NPs were significantly distinguished from control treatment, which was mainly explained by EO yield and TFC attributes. Conclusion Foliar-applied Si-NPs was the rapidly and highly effective practice to reach the optimum antioxidant capacity and EO yield of coriander plants when experience moderate drought stress.

Plants of the Daucus genus (Apiaceae) are used worldwide as traditional medicines or culinary ingredients. In this work, in order to explore a new chemotype, the essential oil obtained from the aerial parts of Daucus reboudii Coss., collected from the National Park of Gouraya (Bejaïa, Algeria), was analyzed by GC-MS. Twenty-eight compounds were identified, accounting for 96.6% of the total oil. (E)-anethol was the main constituent (59.4%), followed by estragol (21.2%) and dodecanal (4.4%). (E)-anethol is an uncommon constituent of Daucus genus, hence it could be considered as a marker that contributes to differentiating D. reboudii from other species. Metal chelating, ABTS•+ and DPPH• assays were performed to determine the antioxidant activity. The highest activity was revealed by the DPPH• method, where D. reboudii essential oil showed a significantly higher activity compared to the reference standard BHT at doses of 50 and 100 µg/mL. Results suggest that the essential oil from D. reboudii could have a potential use in the food industry as food preservative. Nevertheless, further studies are needed to assess its applicability, and to elucidate also the composition of non-volatile compounds of this plant. This research was funded by the Ministry of Higher Education and Scientific Research of Algeria.

[EN] Chemical characterization of clementine varieties (Citrus clementina Hort. ex Tan.) essential oils (EO) can lead to variety identification and valorization of their potential use in food and aroma industries. The goal of this study was the chemometric discrimination between two very closely related and morphologically identical clementine varieties, Clemenules (NL) and Clemenpons (PO), based on their rind EO, to identify the differential volatile organic compounds (VOCs) and to determine their antioxidant capacity. EO rind volatile profile was determined by gas chromatography coupled to mass spectrometry in Citrus fruit at different ripening stages grown two independent years in two different locations. Untargeted metabolomics and multivariate data analysis showed an evolution of EO volatile profiles markedly parallel in both varieties. Although EO qualitative composition was identical in both varieties, PLS-DA allowed the identification of characteristic VOCs, quantitatively discriminating them along all the ripening process. PO showed higher accumulation of several mono- and sesquiterpene compounds such as trans-carveol, while NL showed higher levels of aldehyde and alcohol non-terpenoids like dodecanal. Both varieties evinced identical EO antioxidant activities, indicating a similar value for food preservation. Hence, untargeted metabolomics approach based on rind EO volatiles was revealed as a powerful technique able to differentiate between morphologically undistinguishable Citrus varieties., This work was funded by the European Commission H2020 research and innovation program through the TOMGEM project (679796.), TRADITOM project (634561), SusCrop-ERA-NET proposal SOLNUE, and Spanish Ministry project BIO2016-78601-R. J.L. Rambla is supported by the Spanish Ministry of Economy and Competitiveness through a Juan de la Cierva-Formacion grant (FJCI-2016-28601).

There are various secondary metabolites that have been identified in Polygonum minus Huds. or kesum plant, but the production is often very low and depending on growth stage. Therefore, elicitation and in vitro techniques have been suggested as an effective way for inducing secondary metabolites production in plant. This study was conducted to determine the optimal conditions for P. minus root formation in vitro and to profile the metabolite content from P. minus root culture with and without elicitor treatment. From the root induction study, it was found that the fresh weight of induced root for nodal explant in MS liquid media supplemented with 0.5 mg/L NAA and shaken had the highest production (0.38±0.08 g) compared to other treatments including the control. The results from metabolite profile showed that the volatile compound of P. minus root produced without any elicitation contained 50.11% aliphatic (27.59% aldehide, 9.17% alkane and 13.35% others) and 19.39% sesquiterpene (β-caryophyllene, α-bergamotene, β-farnesene, α-caryophyllene dan β-curcumene) where the dodecanal compound (22.27%) and β-caryophyllene (8.09%) have the highest percentage value for aliphatic and sesquiterpene group, respectively. Moreover, elicitation of P. minus root culture using yeast extract at 100 mg/L concentration for 1 day demonstrated the ability to increase the production of secondary metabolites in many volatile compounds of kesum in vitro root including the sesquiterpene compounds compared to control treatment and other yeast extract elicitation treatments.

Hawk tea, prepared from the young leaves of Litsea coreana Levl. var. lanuginosa, is consumed as a tonic in China. Essential oils (EOs) from Hawk tea collected from six habitats in China were obtained by hydro distillation. Extraction yields ranged from 0.42% (g/g) in samples from Ningguo to 0.11% (g/g) in samples from Qingchuan. A total of 50 compounds in the six EO samples were identified by Gas Chromatography-Mass Spectrometer. The dominant compounds were citral (4.67–21.12%), caryophyllene (2.31–15.74%), dodecanal (2.10–15.38%), α-humulene (1.45–13.56%) and decanal (1.91–13.17%). Altitude may contribute the greatest effect on the chemical variation of the six EO samples. All the EO samples showed bioactivities. Among them, the EOs from the Pingshan sample showed the best ABTS radical scavenging activity (78.67 mg TEs /g) and better antimicrobial activities (MIC = 156.25–625 μg/mL) and had stronger DPPH radical scavenging activity (IC50 = 0.71 mg/mL) than BHT (IC50 = 0.76 mg/mL). The EOs from the Ningguo sample showed the highest reducing power (26.06 mg Fe2+/g) in a FRAP assay, the best inhibitory effect on α-glucosidase (1.71 mg/mL) and was the most cytotoxic (66.03–77.03 μg/mL) in an MTS assay. Therefore, the EOs from Hawk tea could be suitable for commercialization in the food, cosmetic or medical industries. Due to the activities of their EOs, plants growing in Pingshan and Ningguo are the optimal candidates.

This study was conducted to determine the essential oil components in Macrura pomifera, a North American plant. The essential oil components were determined by GC / MS method after the essential oil isolation of the fruit sample was completed. The relative abundances of the chromatograms obtained as a result of the analyses were compared with the similarity indices of the probable results in the library of the GC / MS for the highest peaks and retention index calculations were made from the retention time. As a result of the analyzes, the structure of 28 essential oil components in the fruit was clarified. When the components were examined, dodecanal (9.05%), Eugenol (8.36%) and α-humulene (7.84%) emerged as the first three major components. Other compounds are less common than these three compounds., Thisstudy was conducted to determine the essential oil components in Macrura pomifera,a North American plant. The essential oil components were determined by GC / MSmethod after the essential oil isolation of the fruit sample was completed. Therelative abundances of the chromatograms obtained as a result of the analyses werecompared with the similarity indices of the probable results in the library of theGC / MS for the highest peaks and retention index calculations were made from theretention time. As a result of the analyzes, the structure of 28 essential oil componentsin the fruit was clarified. When the components were examined, dodecanal (9.05%),Eugenol (8.36%) and α-humulene (7.84%) emerged as the first three major components.Other compounds are less common than these three compounds.

The leaves of harvested tea [Camellia sinensis (L.) O. Kuntze] can be processed into different products such as black tea, green tea and oolong tea. Black tea is the mostly consumed worldwide among these products. Black tea production is achieved by a series of processing steps namely withering, rolling, fermentation, drying, sieving and packaging. Rolling is one of the most important steps in the production as it ensures uniform maceration of tea leaves and promotes oxidation reactions catalysed by phenol oxidase enzymes during the fermentation process. The rolling of tea leaves is generally performed by either Crushing-Tearing-Curling (CTC), rotorvane or Orthodox methods. However, in Turkey, rolling is also performed using a combination of rotorvane and orthodox which is called the “CAYKUR” method. The rolling method provides a unique taste and flavours. Thus, this study was conducted to compare volatile constituents of the black teas produced by the above rolling methods and to determine the volatiles during the 6-month storage period. Some specific compounds such as 2,6-nonadienal, 3-hexen-2-one and dodecanal for CAYKUR, 2,5-octanedione for Orthodox and methylpyrazine for CTC were identified to differentiate the rolling system. This study also showed that a few compounds can be used as markers of storage. The number and amounts of volatiles, especially compounds with a high molecular weight, increased by storage. In addition, the flavour quality of the teas was evaluated by the Wickremasinghe–Yamanishi ratio (WYR), Mahanta ratio (MR) and Owuor Flavour Index.

The volatile composition of yogurt produced by Streptococcus thermophilus fermentation at different time points was investigated by gas chromatography-mass spectrometry combined with simultaneous distillation and extraction. A total of 53 volatile compounds including 11 aldehydes, 10 ketones, 8 acids, 7 benzene derivatives, 13 hydrocarbons, and 4 other compounds were identified in all of the samples. Ketones and hydrocarbons were the predominant volatile components in the early stage, whereas acids were the predominant volatiles in the late stage. The importance of each volatile was evaluated based on odor, threshold, and odor activity values (OAVs). Twenty-nine volatiles were found to be odor-active compounds (OAV > 1), among which (E, E)-2,4-decadienal had the highest OAV (14623–22278). Other aldehydes and ketones such as octanal, dodecanal, 2-nonen-4-one, and 2-undecanone also showed high odor intensity during fermentation. Heat map analysis was employed to evaluate the differences during fermentation. The results demonstrated that the volatile profile based on the content and OAVs of volatile compounds enables the good differentiation of yogurt during fermentation.

Escherichia coli and salivary Klebsiella oxytoca and Staphylococcus saccharolyticus were subjected to different concentrations of silver nanoparticles (AgNPs), namely: 12.5, 50, and 100 &micro, g mL&minus, 1. Matrix-assisted laser desorption/ionization&ndash, time-of-flight mass spectrometry (MALDI-TOF MS) spectra were acquired after specified periods: 0, 1, 4, and 12 h. For study of volatile metabolites, headspace solid-phase microextraction coupled to gas chromatography/mass spectrometry (HS-SPME-GC-MS) was employed&mdash, AgNPs were added to bacteria cultures and the headspace was analyzed immediately and after 12 h of incubation. Principal components analysis provided discrimination between clusters of protein profiles belonging to different strains. Canonical correlation, network analysis, and multiple linear regression approach revealed that dimethyl disulfide, dimethyl trisulfide, 2-heptanone, and dodecanal (related to the metabolism of sulfur-containing amino acids and fatty acids synthesis) are exemplary molecular indicators, whose response variation deeply correlated to the interaction with bacteria. Therefore, such species can serve as biomarkers of the agent&rsquo, s effectiveness. The present investigation pointed out that the used approaches can be useful in the monitoring of response to therapeutic treatment based on AgNPs. Furthermore, biochemical mechanisms enrolled in the bactericidal action of nanoparticles can be applied in the development of new agents with enhanced properties.

Plant derived compounds are a source of long term research focus due to their applications in a variety of fields, particularly food preservation. One key way in which phytochemicals are crucial in this area is by disrupting enzyme functionality. In this work, essential oil was extracted by steam distillation from the fresh leaves of Polygonum odoratum (Polygonaceae), commonly known as Vietnamese coriander, and shown to effectively inhibit the oxidation of L-3,4-dihydroxyphenylalanine (L-DOPA) catalyzed by mushroom tyrosinase (EC1.14.18.1). Using GC-MS analysis, twenty five compounds were identified in the essential oil. The most abundant compounds in the essential oil were Alkanals - dodecanal (55.49%), and decanal (11.57%) - followed by anisaldehyde (6.35%); these compounds were individually investigated for inhibitory activity by performing single-compound screening. Each of the top three most abundant compounds inhibited the tyrosinase-catalyzed oxidation of L-DOPA, as identified by UV-VIS spectroscopy and oxygen consumption assays. The inhibitory activity of the major compounds increased when pre-incubated with tyrosinase and without significant additional oxygen consumption, suggesting kcat-type inactivation is not involved. Interactions of the head and tail components of the major alkanals may disrupt the tertiary structure of the enzyme, presenting a potential inhibitory mechanism., Food science; Food technology; Biochemistry; Biotechnology; Plant biology; Natural products; Enzyme inhibition; Mushroom tyrosinase; Polygonum odoratum; Food preservation

The volatile aroma compounds of traditional Chinese rose vinegar were identified by headspace solid-phase micro extraction gas chromatography–mass spectrometry (HS–SPME–GC–MS) and GC–MS–olfactometry (GC–MS–O), and the metabolites were identified by silylation–GC–MS in this study. A total of 48 and 76 kinds of flavors and metabolites, respectively were detected in this study. Quantitative analysis showed that aldehydes and acids were present in relatively high amounts. Furthermore, the data colleted by the calculated odor activity values (OAVs) suggested that aldehydes are likely to contribute greatly to the aroma of traditional Chinese rose vinegar, especially, nonanal (OAV: 133, rose), 3–methyl–butanal (OAV: 57, apple-like), decanal (OAV: 23, orange peel), heptanal (OAV: 17, fruity), and dodecanal (OAV: 4–9, violet scents). Moreover, among the detected nonvolatile acids, 14 kinds of hydroxy acids, such as lactic acid, citric acid, 3–phenyllactic acid (PLA) and d –gluconic acid were detected in rose vinegar. The acids provide a well buffer system, not only greatly reduce the irritation of acetic acid, but also improve the flavor of rose vinegar. This study suggests that the fragrance and sour notes in rose vinegar are from aldehydes and hydroxy acids.

Powdered mealworm (MW) and buffalo worm (BW) larvae were used to functionalize sourdough Italian-style breads. Sourdough inoculum was started with Levilactobacillus brevis, Weissella cibaria and Leuconostoc citreum. The doughs were SBS (semolina plus powdered BW larvae and sourdough) and SMS (semolina plus powdered MW larvae and sourdough) whose pHs (4.32 and 4.21, respectively) were higher than that of control (3.81). The highest fermentation quotient (lactate/acetate molar ratio) was recorded in SMS (4.46). LAB reached viable counts of about 109 CFU g−1 in almost all doughs. Insects impacted bread VOCs with dodecanal, 2.4-dodecadienal and 2-octenal-2-butyl. SBS and SMS increased the antioxidant capacity of breads by 42 and 69%, respectively. SMS decreased the glucose release in the bio-accessible fraction by 70% reducing the glycemic index of bread. Control breads were more appreciated by the sensory panel than insect-containing breads, though SMS breads were characterized by a slightly lower overall assessment.

Coriander ( Coriandrum sativum L.) is mainly cultivated for its fruits and/or leaves, which are used for different purposes such as food, drugs, and spice as both a fresh and dried herb. To determine the effect of drying methods on essential oil of coriander, the stem and leaves of an Iranian landrace of coriander were dried in sunlight, shade, mechanical ovens (40 and 60 °C), microwave oven (500 and 700 W), and by freeze–drying. The essential oils were analyzed using GC-FID and GC/MS. The highest essential oil yield was obtained from freeze–dried tissue followed by the shade–dried sample. In total, 39 components were determined in the essential oils from fresh and dried coriander. The main components were decanal (0–37.5%), cis -phytol (1.0–34.1%), 1-tetradecanol (trace – 31.7%), 2 E -dodecenal (8.3–17.2%), dodecanal (0.5–14.8%), n -decanol (0.5–14.8%), trans -2-undecen-1-ol (trace – 12.9%), 2 E -decenal (0–11.3%), 1-eicosanol (0–6.4%), and methyl chavicol (0–6.0%). The percentages of decanal and n -decanol in the oil, however, decreased significantly when the plant material was dried in the oven at 60 °C or microwaved. The percentages of 1-tetradecanol, 1-eicosanol, and cis -phytol increased significantly when the plant tissue was dried in the oven at 60 °C or microwaved. Generally, the drying of coriander in freeze–drying is most suitable and can be recommended for high–oil yield.

Acylation of 2,2':5',2''-terthiophene and biphenyl gave 1-(2,2':5',2''-terthiophen-5-yl)dodecan-1-one and 1-(biphenyl-4-yl)dodecan-1-one, which upon treatment with phosphorus oxychloride and dimethylformamide were converted to 2-[(2,2':5',2''-terthiophen-5-yl)-chloromethylidene]dodecanal and 2-[(biphenyl-4-yl)chloromethylidene]dodecanal. The reaction of these compounds with ethyl 2-mercaptoacetate led to the formation of ethyl 3-decyl-2,2':5',2'':5'',2'''-quaterthiophene-5- and 5-(biphenyl-4-yl)-4-decylthiophene-2-carboxylates, which are of interest as building blocks for the synthesis of organic semiconductors. Ethyl 3-decyl-2,2':5',2'':5'',2'''-quaterthiophene-5-carboxylate was also obtained by palladium-catalyzed cross coupling of ethyl 5'-bromo-3-decyl-2,2'-bithiophene-5-carboxylate with 2,2'-bithiophene.

El género Peperomia (Piperaceae), es bien conocido por sus especies ornamentales y usos etnomedicinales. En el presente trabajo se describe la caracterización química y la actividad antibacteriana del aceite esencial de Peperomia acuminata Ruiz & Pav. proveniente del Estado Mérida Venezuela. El aceite esencial se obtuvo por hidrodestilación de las hojas y la separación de los componentes se realizó por Cromatografía de gases-Espectrometría de Masas (CG/EM). Se logró la elucidación de ocho compuestos (96,7%), siendo el 2E-dodecenal el componente mayoritario (65%) seguido de dodecanal (14,8%) y tetradecanal (9,2%). Esta investigación muestra el potencial del aceite esencial de P. acuminata frente a bacterias Gram positivas (Staphylococcus aureus ATCC 25923 y Enterococcus faecalis 29212), con un valor de Concentración inhibitoria mínima de 1μL/mL. Este es el primer reporte sobre la composición química del aceite esencial de esta especie, por lo tanto una contribución importante al estudio del género Peperomia.

This research focuses on extraction of medicinal plant Launaea acanthodes ( L. acanthodes ) by using supercritical carbon dioxide (SC CO 2 ) and hydro-distillation (HD) methods. The influence of pressure, temperature, flow rate and volume of co-solvent on the extraction yield of L. acanthodes was investigated by response surface methodology (RSM) and artificial neural network (ANN). The error values of RSM (R 2 = 0.9871, MSE = 0.000016 and AARD = 2.395) and ANN (R 2 = 0.9968, MSE = 0.0000057 and AARD = 1.301) were calculated. The results exhibited that both models have the ability to predict the experimental data, but ANN was more reliable than the RSM. The maximum extraction yield was estimated by RSM to be 1.0250% under the operational conditions of pressure 240 bar, temperature 328 K, flow rate 4.06 g/min and co-solvent 663 μl; whereas the optimum extraction yield estimated by hybrid ANN-GA method was 1.0238% applying the operational conditions of pressure 240 bar, temperature 328 K, flow rate 3.98 g/min and co-solvent 650 μl. The maximum yield (1.0238%) obtained at the optimal conditions was more than that achieved by hydro-distillation method (0.7530%). The extracted components obtained from both methods were analyzed by GC/MS and GC-FID. The main compounds found in the extracts were γ-Phenylbutyric acid (9.29, 9.19%), Geranyl acetone (7.67, 7.87%), n -Hexadecane (7.34, 6.26%), ( Z )-3-Hexen-1-yl-benzoate (7.10, 6.91%), n -Dodecanal (5.87, 6.56%), (2Z,6E)-Farnesol (5.65, 4.34%) and Benzoic acid n -hexyl ester (5.13, 4.51%) and β-Ionone (4.55, 4.58%) for SC CO 2 and HD methods, respectively. To the best of our knowledge, this is the first report on the extraction of essential oil from L. acanthodes.

5 páginas.-- 4 figuras.-- 24 referencias.-- Supporting information for this article can be found under: http://dx.doi.org/10.1002/anie.201604915., Este artículo está en abierto en el enlace de la revista y puede descargar el pdf. original, A new heme–thiolate peroxidase catalyzes the hydroxylation of n-alkanes at the terminal position—a challenging reaction in organic chemistry—with H2O2 as the only cosubstrate. Besides the primary product, 1-dodecanol, the conversion of dodecane yielded dodecanoic, 12-hydroxydodecanoic, and 1,12-dodecanedioic acids, as identified by GC–MS. Dodecanal could be detected only in trace amounts, and 1,12-dodecanediol was not observed, thus suggesting that dodecanoic acid is the branch point between mono- and diterminal hydroxylation. Simultaneously, oxygenation was observed at other hydrocarbon chain positions (preferentially C2 and C11). Similar results were observed in reactions of tetradecane. The pattern of products formed, together with data on the incorporation of 18O from the cosubstrate H218O2, demonstrate that the enzyme acts as a peroxygenase that is able to catalyze a cascade of mono- and diterminal oxidation reactions of long-chain n-alkanes to give carboxylic acids., The research was financed by the project NCN DEC-2012/07/B/ST5/02448 and the research program P1-0055 of the Slovenian Research Agency. Authors thank Prof. Mojca Cepic and Prof. Hideo Takezoe for valuable discussions.

The chemical composition of the essential oil (EO) obtained from the aerial parts of Stachys benthamiana Boiss. was analyzed by GC and GC-MS. Thirty-four components were identified in the oil. Undecanoic acid (20.86%), dodecanoic acid (14.49%), dodecanal (11.07%), caryophyllene oxide (9.4%), spathulenol (8.6%), decanoic acid (6.84%) and β-eudesmol (4.94%), were the main compounds in the EOs. This is the first report of different chemical compositions of S. benthamiana EOs from the southern Zagros of Iran.

Yarrowia lipolytica possesses twelve ALK genes, which encode cytochromes P450 in the CYP52 family. In this study, using a Y. lipolytica strain from which all twelve ALK genes had been deleted, strains individually expressing each of the ALK genes were constructed and their roles and substrate specificities were determined by observing their growth on n-alkanes and analyzing fatty acid metabolism. The results suggested that the twelve Alk proteins can be categorized into four groups based on their substrate specificity: Alk1p, Alk2p, Alk9p, and Alk10p, which have significant activities to hydroxylate n-alkanes; Alk4p, Alk5p, and Alk7p, which have significant activities to hydroxylate the ω-terminal end of dodecanoic acid; Alk3p and Alk6p, which have significant activities to hydroxylate both n-alkanes and dodecanoic acid; and Alk8p, Alk11p, and Alk12p, which showed faint or no activities to oxidize these substrates. The involvement of Alk proteins in the oxidation of fatty alcohols and fatty aldehydes was also analyzed by measuring viability of the mutant deleted for twelve ALK genes in medium containing dodecanol and by observing growth on dodecanal of a mutant strain, in which twelve ALK genes were deleted along with four fatty aldehyde dehydrogenase genes. It was suggested that ALK gene(s) is/are involved in the detoxification of dodecanol and the assimilation of dodecanal. These results imply that genes encoding CYP52-family P450s have undergone multiplication and diversification in Y. lipolytica for assimilation of various hydrophobic compounds.

The object of this study is the flowers of Kazakhstan species of “AkMai” safflower, collected in the flowering stage in Southern Kazakhstan. Volatile oil was carry out to study the component composition of Kazakhstan “AkMai” safflower flowers. The composition of the volatile oil obtained from the dried flowers of Carthamus tinctorius L. growing in Kazakhstan. Pale yellow oily extracts were obtain by varying the process parameters. The volatile oil obtained by hydrodistillation of the petals Carthamus tinctorius L. was analyzed by gas chromatography/mass spectrometry (GC/MS). The yield of the oil was 0.175 % (v/w). 20 compounds representing 99.81% of the oil were characterized. Volatile oil from the flowers of Kazakhstan safflower species "AkMai" were investigated by gas chromatography/mass spectrometry GC/MS which allowed detecting 20 compounds. The volatile oil was found rich in undecanoic acid, octane, 2-nonen -1-ol, hexadecanal, dodecanal, dec-2-en-1-ol, nonanoic acid, tetradecanoic acid, 2 pentadecanone, 6,10,14trimethyl, 1,2-benzenedicarboxylic acid, isobutyl-beta-phenylpropionate, 1.3-cyclohexadiene, myrtenoic acid, octadecanoic acid, heneicosanoic acid, 2(3H)-furanone, 4,4-dipropylheptane, hexcosane,1-eicosanol, and also heptocosane.

Most of the studies concerning the optimal harvest date of aromatic herbs have dealt with different parts of plant such as flowers, leaves, stems, roots and seeds, but none have evaluated the effect of different harvest date at different vegetative stages on shoots (leaves and stems). Therefore, the main objective was to investigate the effects of harvest date of two consecutive seasons on the volatile composition of shoots of 4 aromatic herbs (dill, parsley, coriander and mint) widely cultivated worldwide. The impact of harvest date during the evolution of vegetative part of four aromatic herbs (parsley, dill, coriander and mint) was investigated. Volatile compounds of shoots of the four herbs were identified by GC–MS. The main compounds were 1,3,8-p-menthatriene, beta-phellandrene, myristicin and myrcene for parsley, alpha-phellandrene, dillether and beta-phellandrene for dill, decanal, E-2-dodecenal, 1-decanol and dodecanal for coriander, and carvone and limonene in case of mint. There was a significant effect of harvest date on the content of volatile compounds of the four species. The results showed that highest total concentration of volatiles and therefore the optimal harvest date of parsley was found 9 weeks after planting date with a total concentration of 2543 mg kg−1, for dill was 2619 mg kg−1 14 weeks after planting date, for coriander was 2191 mg kg−1 3 weeks after planting date, and 23329 mg kg−1 for mint 6 weeks after planting date.

In order to optimize the temperature-resistant and thickening performance of single anionic Gemini surfactant in cleaning fracturing fluid, and to explore the thickening effect and mechanism of additives on its solution viscosity, the effects of the preferred novel sulfonate Gemini surfactant(DS18-3-18) concentration, NaCl, dodecanal, SDBS, and nano-MgO on the viscosity of DS18-3-18 solution were systematically studied by MR301 rheometer at 90 ℃ andγ = 170 s−1; and the microstructure of the solution was studied by scanning electron microscopy. The results showed that the greater the concentration of DS18-3-18 solution, the stronger its tackifying ability, and the optimal concentration is 4%. The addition of NaCl reduced the viscosity of 4% DS18-3-18 solution, while the additives of dodecanol, SDBS, and nano-MgO can effectively improve the viscosity of 4% DS18-3-18 solution at high temperature. The optimal system of 4% DS18-3-18 and 3% dodecanol was selected, which could meet the requirement of 25 mPa s for the effective carrying of proppant in clean fracturing fluid at 90 ℃ and its microstructure showed that the arrangement of close-packed sheet micelles was beneficial to improve the temperature resistance and thickening performance. What’s more, this phenomenon provides the experimental and theoretical basis for the thickening system of DS18-3-18 in cleaning fracturing fluid.

Recent studies provide a convincing support that the presence of cancer cells in the body leads to the alteration of volatile organic compounds (VOCs) emanating from biological samples, particularly of those closely related with tumoral tissues. Thus, a great interest emerged for the study of cancer volatilome and subsequent attempts to confirm VOCs as potential diagnostic biomarkers. The aim of this study was to determine the volatile metabolomic signature of bladder cancer (BC) cell lines and provide an in vitro proof-of-principle that VOCs emanated into the extracellular medium may discriminate BC cells from normal bladder epithelial cells. VOCs in the culture media of three BC cell lines (Scaber, J82, 5637) and one normal bladder cell line (SV-HUC-1) were extracted by headspace-solid phase microextraction and analysed by gas chromatography-mass spectrometry (HS-SPME/GC–MS). Two different pH (pH 2 and 7) were used for VOCs extraction to infer the best pH to be used in in vitro metabolomic studies. Multivariate analysis revealed a panel of volatile metabolites that discriminated cancerous from normal bladder cells, at both pHs, although a higher number of discriminative VOCs was obtained at neutral pH. Most of the altered metabolites were ketones and alkanes, which were generally increased in BC compared to normal cells, and alcohols, which were significantly decreased in BC cells. Among them, three metabolites, namely 2-pentadecanone, dodecanal and γ-dodecalactone (the latter only tentatively identified), stood out as particularly important metabolites and promising volatile biomarkers for BC detection. Furthermore, our results also showed the potential of VOCs in discriminating BC cell lines according to tumour grade and histological subtype. We demonstrate that a GC–MS metabolomics-based approach for analysis of VOCs is a valuable strategy for identifying new and specific biomarkers that may improve BC diagnosis. Future studies should entail the validation of volatile signature found for BC cell lines in biofluids from BC patients.

This study reports the chemical composition, antioxidant, and antimicrobial activity of the essential oil and ethanol extract of Coriandrum sativum L. leaves. Gas chromatography/mass spectrometry analysis identified 19 compounds representing 95.30% of the oil. (E)-2-decenal (29.87%), linalool (21.61%), (E)-2-dodecenal (7.03%), dodecanal (5.78%), (E)-2-undecenal (3.84%), (E)-2-tridecenal (3.56%), (E)-2-hexadecenal (2.47%), tetradecenal (2.35%), and α-pinene (1.64%) were the main components identified in the essential oil. The samples were screened for their antioxidant activities using 2,2-diphenyl-1-picrylhydrazyl radical scavenging and β-caroten bleaching assay. IC50 value for ethanol extract of C. sativum was determined as 74.87 ± 0.03 μg/mL. Total antioxidant activity value for C. sativum ethanol extract was 85.85 ± 0.04%. Total phenolic content for ethanol extract of the plant was determined as 14.97 ± 0.05 mg gallic acid equivalents/g dry weight. The essential oil and ethanol extract were also tested...

Volatiles of six sweet orange essential oils with different origins were characterized by descriptive sensory analysis, gas chromatography-mass spectrometry (GC-MS) and gas chromatography-olfactometry (GC-O). Six attributes (green, fruity, peely, fatty, floral and wood) were selected to assess sweet orange essential oils, in which 64 volatile compounds were detected by GC-MS. Monoterpenes constituted the largest chemical group among the volatiles of the essential oils. Thirty-one aroma compounds having more than a 50% detection frequency and large span were selected as major odour active compounds correlated with sensory evaluation assessed by partial least squares regression (PLSR). The correlation result showed α-pinene, sabinene, limonene, δ-terpinolene, hexanal, octanal, decanal and dodecanal were typical aroma compounds, which co-varied with a characteristic aroma of the sweet orange essential oil. Copyright © 2015 John Wiley & Sons, Ltd.

This study collected 120 figs, classified them into six degrees of maturity according to hardness values, and analyzed contents of organic acids and free sugars. Volatile compounds in figs were investigated using the solid- phase microextraction method of gas chromatography/mass spectrometry. For measurement of texture, elasticity increased up to stage 4 and decreased again. Cohesiveness and brittleness increased with maturation. Organic acids in figs were mainly composed of citric acid, malic acid, and tartaric acid in the final stage. Fructose and glucose were the major sugar components of figs. Fructose content decreased from stage 1 to stage 4 and then increased significantly. One hundred and nineteen volatile compounds were identified in figs, and classes were 14 acids, 15 alcohols, 23 aldehydes, 10 esters, 33 hydrocarbons, 11 ketones, four aromatics, six miscellaneous, and five terpenes. The dominant volatile components in figs were hexadecanoic acid, hexane, dodecanal, DL-limonene, 2-hexanal, nonanal, and 6-methyl-5-hepten-2-one.

Essential oil of the leaves of Ducrosia anethifolia (DC.) Boiss. from Iran was extracted by hydrodistillation (HD), steam distillation (SD) and supercritical fluid extraction (SFE). The constituents of the essential oils extracted with those three methods were analyzed by GC-MS. Kovates indexes and mass spectra of standard substance was employed for compounds identification. 30, 32 and 28 compounds detected in the HD, SD and SFE extracts, respectively. The major components of HD extract were n-decanal (30.31 %), dodecenal (14.35 %) and n-decanol (11.04 %). The major components of SD extract were n-decanal (27.64 %), dodecanal (15.26 %), n-decanol (14.06 %) and dodecenal (9.80 %) and the major components of SFE extract were n-decanal (25.67 %), dodecanal (17.25 %) and dodecenal (16.23 %).

Convolvulus persicus L. (Convolvulaceae) is distributed in the Southern coasts of Caspian Sea. The aerial parts of this species were collected from Sari (Mazandaran, Iran) in July 2012. The chemical composition of the essential oil obtained by hydrodistillation of the aerial parts of C. persicus was investigated by GC and GC-MS. Twenty components, representing 89.0 % of the total oil, were characterized with β-caryophyllene (47.0 %), dodecanal (8.8 %), caryophyllene oxide (5.7 %), tetradecanal (4.4 %) and dihydroedulan I (4.4 %) as the major components. This is the first report on the analysis of the essential oil from a species of Convolvulus genus.

Essential oil derived from the fresh leaves of Polygonum odoratum Lour was tested for their effects on a foodborne bacterium Salmonella choleraesuis subsp. choleraesuis ATCC 35640 using a broth dilution method. This essential oil showed a significant antibacterial activity against S. choleraesuis at the concentration of 200 µg/mL. Twenty-five volatile compounds were characterized from this essential oil by GC-MS, and aldehyde compounds were found abundant and accounted for more than three-fourths of the essential oil. Among the compounds characterized, dodecanal (C12) was the most abundant (55.5%), followed by decanal (C10) (11.6%). Both alkanals were effective against S. choleraesuis with the minimum growth inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values of 100 µg/mL. The most potent antibacterial activity against this bacterium was found with two minor compounds, dodecanol (lauryl alcohol) and 2E-dodecenal, both with each MBC of 6.25 µg/mL. Their primary antibacterial action against S. choleraesuis provably comes from their ability to function as nonionic surface-active agents (surfactants), disrupting the native function of integral membrane proteins nonspecifically. Thus, the antibacterial activity is mediated by biophysical processes. In the case of 2E-alkenals, a biochemical mechanism is also somewhat involved, depending on their alkyl chain length. Copyright © 2015 John Wiley & Sons, Ltd.

Multiwall carbon nanotubes supported MoO3 (Mo/MWCNTs) and potassium containing Mo/MWCNTs (K/Mo/MWCNTs) catalysts were prepared and characterized with XRD, N2-physisorption, SEM, TEM, NH3-TPD, and TGA/DTA. Increasing the Mo content (5–15 wt%) in Mo/MWCNTs samples diminished BET surface area and pore volume with concomitant increase of MoO3 particle size. Potassium addition to Mo/MWCNTs resulted in apparent decrease of their acid amounts and MoO3 particle sizes. These catalysts were utilized for selective oxidation of 1-dodecanol (DCOL) with air to obtain 1-dodecanal (DCAL). Various reaction parameters were investigated. It was found that K/Mo/MWCNTs exhibited much better catalyst performance than Mo/MWCNTs. Potassium loading on Mo/MWCNTs greatly enhanced DCOL conversion, DCAL selectivity, and catalyst stability due to smaller MoO3 particles and decreased acid sites.

Polygonum minus Huds. is an aromatic plant with potential anti-inflammatory, antiulcer and diuretic properties. Although the volatile compounds from the essential oil of P. minus have been extensively studied, knowledge of the aroma-active compounds is still incomplete. Hence, the aim of this study is to investigate and to characterise the aroma-active compounds that contribute to the potent odour of P. minus. Essential oil was extracted from the leaves of kesum (P. minus) using hydrodistillation and was analysed by gas chromatography-mass spectrometry (GC-MS) to identify the volatile constituents. The important aroma-active compounds were further analysed by GC-MS/Olfactometry (GC-MS/O) and aroma extraction dilution analysis (AEDA). The GC-MS analysis using Kovats retention indices detected 39 volatile compounds in the essential oil. Aldehydes represented the major class of compounds, encompassing 75.43% of the total peak area, followed by sesquiterpenes (13.19%), alcohols (8.07%) and organic acids (0.83%). The dominant components of the kesum essential oil were dodecanal (54.25%) and decanal (18.27%) in the aldehyde group. The sesquiterpenes that were detected include β-farnesene (1.74%), α-caryophyllene (1.72%), β-caryophyllene oxide (1.51%) and βselinene (1.36%). In this study, GC-MS/O and AEDA analysis identified dodecanal, decanal, farnesol, 1-nonanal and α-bergamotene as the main contributors to the characteristic fragrance of this plant. This is the first olfactometric study on the essential oil of P. minus, and it is important for our understanding of the biosynthesis of volatile compounds in this medicinal herb. Moreover, the characterisation of aromatic compounds that contributed to the potent odour of P. minus can be further applied in the flavour and fragrance industries.

Essential oils of the leaf and root of Eryngium foetidum L. from Port Blair (Andaman and Nicobar) and Nadugani (Tamil Nadu) in India were investigated by GC and GC-MS analyses. The oils of the leaf and root from the two locations were found to contain alkanes, alkanals, alkenals, fatty acids, aromatic aldehydes, mono-, sesqui- and diterpenes, aromatic aldehydes and terpene aldehyde esters. The main components of the oil of the leaf from Port Blair were identified as a trimethyl benzaldehyde (16.5 %), dodecanal (4.7 %), muurola- 4,10(14)-dien-1α-ol (10.2 %), neophytadiene isomer (4.5 %), hexahydrofarnesyl acetone (5.5 %), palmitic acid (4.6 %) and phytol (4.9 %). The composition of the root oil from Port Blair was found to be qualitatively similar to that of leaf oil, having the major constituents two isomers of trimethyl benzaldehydes (4.00 % and 57.0 %) and 2-formyl 1,1,5-trimethyl 2,5-cyclohexadien-4-yl-2-methylbutenoate (4.9 %). The leaf and root oils from Nadugani were found to be qualitative...

The volatile organic compounds (VOCs) produced by antagonistic microbes have great antifungal potential against soil-borne fungal pathogens. The VOCs produced by Paenibacillus polymyxa strain WR-2 in the presence of root exudates and organic fertilizer were identified and their effects on the growth and spore germination of Fusarium oxysporum f. sp. niveum were evaluated. The VOCs produced by WR-2 inhibited the growth of F. oxysporum by 38%, 36% and 40% in agar medium, sterilized soil and natural soil, respectively. This inhibitory effect was increased to 60%, 58% and 64% with the addition of organic fertilizer in agar medium, sterilized soil and natural soil, respectively. The addition of root exudates did not affect the production of antifungal VOCs by WR-2. The VOCs produced by WR-2 completely inhibited the germination of F. oxysporum spores. Out of 42 identified VOCs, seven VOCs; benzothiazole, benzaldehyde, undecanal, dodecanal, hexadecanal, 2-tridecanone and phenol were found to inhibit the growth of F. oxysporum. The results of these experiments suggest another significance of using organic fertilizer as a carrier material with the biocontrol agents to control soil-borne fungal pathogens.

Due to their particular properties, detergents are widely used in household cleaning products, cosmetics, pharmaceuticals, and in agriculture as adjuvants tailoring the features of pesticides or other crop protection agents. The continuously growing use of these various products means that water soluble detergents have become one of the most problematic groups of pollutants for the aquatic and terrestrial environments. Thus it is important to identify bacteria having the ability to survive in the presence of large quantities of detergent and efficiently decompose it to non-surface active compounds. In this study, we used peaty soil sampled from a surface flow constructed wetland in a wastewater treatment plant to isolate bacteria that degrade sodium dodecyl sulfate (SDS). We identified and initially characterized 36 Pseudomonas spp. strains that varied significantly in their ability to use SDS as their sole carbon source. Five isolates having the closest taxonomic relationship to the Pseudomonas jessenii subgroup appeared to be the most efficient SDS degraders, decomposing from 80 to 100% of the SDS present in an initial concentration 1 g/L in less than 24 h. These isolates exhibited significant differences in degree of SDS degradation, their resistance to high detergent concentration (ranging from 2.5 g/L up to 10 g/L or higher), and in chemotaxis toward SDS on a plate test. Mass spectrometry revealed several SDS degradation products, 1-dodecanol being dominant; however, traces of dodecanal, 2-dodecanol, and 3-dodecanol were also observed, but no dodecanoic acid. Native polyacrylamide gel electrophoresis zymography revealed that all of the selected isolates possessed alkylsulfatase-like activity. Three isolates, AP3_10, AP3_20, and AP3_22, showed a single band on native PAGE zymography, that could be the result of alkylsulfatase activity, whereas for isolates AP3_16 and AP3_19 two bands were observed. Moreover, the AP3_22 strain exhibited a band in presence of both glucose and SDS, whereas in other isolates, the band was visible solely in presence of detergent in the culture medium. This suggests that these microorganisms isolated from peaty soil exhibit exceptional capabilities to survive in, and break down SDS, and they should be considered as a valuable source of biotechnological tools for future bioremediation and industrial applications.

Many rhodococci are oleaginous and, as such, have considerable potential for the sustainable production of lipid-based commodity chemicals. Herein, we demonstrated that Rhodococcus jostii RHA1, a soil bacterium that catabolizes a wide range of organic compounds, produced wax esters (WEs) up to 0.0002% of its cellular dry weight during exponential growth on glucose. These WEs were fully saturated and contained primarily 31 to 34 carbon atoms. Moreover, they were present at higher levels during exponential growth than under lipid-accumulating conditions. Bioinformatics analyses revealed that RHA1 contains a gene encoding a putative fatty acyl coenzyme A (acyl-CoA) reductase (FcrA). The purified enzyme catalyzed the NADPH-dependent transformation of stearoyl-CoA to stearyl alcohol with a specific activity of 45 ± 3 nmol/mg · min and dodecanal to dodecanol with a specific activity of 5,300 ± 300 nmol/mg · min. Deletion of fcrA did not affect WE accumulation when grown in either carbon- or nitrogen-limited medium. However, the Δ fcrA mutant accumulated less than 20% of the amount of WEs as the wild-type strain under conditions of nitric oxide stress. A strain of RHA1 overproducing FcrA accumulated WEs to ∼13% cellular dry weight under lipid-accumulating conditions, and their acyl moieties had longer average chain lengths than those in wild-type cells (C 17 versus C 16 ). The results provide insight into the biosynthesis of WEs in rhodococci and facilitate the development of this genus for the production of high-value neutral lipids. IMPORTANCE Among the best-studied oleaginous bacteria, rhodococci have considerable potential for the sustainable production of lipid-based commodity chemicals, such as wax esters. However, many aspects of lipid synthesis in these bacteria are poorly understood. The current study identifies a key enzyme in wax ester synthesis in rhodococci and exploits it to significantly improve the yield of wax esters in bacteria. In so doing, this work contributes to the development of novel bioprocesses for an important class of oleochemicals that may ultimately allow us to phase out their unsustainable production from sources such as petroleum and palm oil.

The aim of this research was to identify the volatile metabolites produced in different organs (leaves, stem and roots) of Polygonum minus, an important essential oil producing crop in Malaysia. Two methods of extraction have been applied: Solid Phase Microextraction (SPME) and hydrodistillation coupled with Gas Chromatography-Mass Spectrometry (GC-MS). Approximately, 77 metabolites have been identified and aliphatic compounds contribute significantly towards the aroma and flavour of this plant. Two main aliphatic compounds: decanal and dodecanal were found to be the major contributor. Terpenoid metabolites were identified abundantly in leaves but not in the stem and root of this plant. Further studies on antioxidant, total phenolic content, anticholinesterase and antimicrobial activities were determined in the essential oil and five different extracts. The plant showed the highest DPPH radical scavenging activity in polar (ethanol) extract for all the tissues tested. For anti-acetylcholinesterase activity, leaf in aqueous extract and methanol extract showed the best acetylcholinesterase inhibitory activities. However, in microbial activity, the non-polar extracts (n-hexane) showed high antimicrobial activity against Methicillin-resistant Staphylococcus aureus (MRSA) compared to polar extracts. This study could provide the first step in the phytochemical profiles of volatile compounds and explore the additional value of pharmacology properties of this essential oil producing crop Polygonum minus.

Leishmaniasis is a chronic infectious disease caused by different Leishmania species. Global occurrences of this disease are primarily limited to tropical and subtropical regions. Treatments are available; however, patients complain of side effects. Different species of plants have been screened as a potential source of new drugs against leishmaniasis. In this study, we investigated the antileishmanial activity of cilantro (Coriandrum sativum) essential oil and its main components: (E)-2-undecenal, (E)-2-decenal, (E)-2-dodecenal, decanal, dodecanal, and tetradecanal. The essential oil of C. sativum leaves inhibits growth of Leishmani donovani promastigotes in culture with an IC50 of 26.58 ± 6.11 µg/mL. The aliphatic aldehydes (E)-2-decenal (7.85 ± 0.28 µg/mL), (E)-2-undecenal (2.81 ± 0.21 µg/mL), and (E)-2-dodecenal (4.35 ± 0.15 µg/mL), all isolated from C. sativum essential oil, are effective inhibitors of in vitro cultures of L. donovani promastigotes. Aldehydes (E)-2-decenal, (E)-2-undecenal, and (E)-2-dodecenal were also evaluated against axenic amastigotes and IC50 values were determined to be 2.47 ± 0.25 µg/mL, 1.25 ± 0.11 µg/mL, and 4.78 ± 1.12 µg/mL, respectively. (E)-2-Undecenal and (E)-2-dodecenal demonstrated IC50 values of 5.65 ± 0.19 µg/mL and 9.60 ± 0.89 µg/mL, respectively, against macrophage amastigotes. These cilantro compounds showed no cytotoxicity against THP-1 macrophages.