Aromatic Constituents Research Articles

Assessment of AMMI model for delineating the stability indices of high yielding variety of Java Citronella (Jor Lab C-5) evaluated in different location of NE India

An industrially important plant, Cymbopogon winterianus Jowitt ex Bor commonly known as Java Citronella belonging to Poaceae family gains its significance due to the presence of aromatic constituents and its capacity to yield a high quantity of essential oil. However, due to varied agronomic and climatic conditions, fluctuations in the chemical constituents and essential oil yield can be noticed. However, till now studies on stability analysis of Citronella are very scarce. Focusing the crop’s exceptional oil-yielding capacity and its high importance in industrial purposes extensive commercial cultivation of superior variety of Citronella is need of the hour. Hence, a study was conducted to establish a stable genotype of Java citronella where Jor Lab C-5 was taken to test the stability along with two check genotypes (Jor lab C-2 and Assam local). For two years (2021-2022 and 2022-2023) six agronomical traits were constantly studied with two sets of environmental factors for the eight different locations in a randomized block design. The Analysis of variance (ANOVA) by regression method revealed herbage recovery rate and essential oil yield as extensively high for Jor Lab C-5 as compared to the other two genotypes. Further, AMMI (Additive Main-effects and Multiplicative Interactions) ANOVA was used for the confirmation of uniform performance of various characters where Jor Lab C-5 was found to be stable in case of plant height, herbage yield, essential oil yield, citronellal content, and total essential oil yield. The GC-MS analysis of essential oil revealed 19 compounds with area percent 94.28% of which citronellal (42.52%) outcomes as major constituent. Additionally, environment such as Runne, Khehoyi, Yaongyimsen, and Jorhat were considered as the best suited locations for Jor Lab C-5, thus highlighting its multi-location stability and its potential industrial significance in the long run.

Deciphering Isotopic Fine Structures of Silylated Compounds in Gas Chromatography-Vacuum Photoionization Orbitrap Mass Spectrometry of Bio-Oils.

We introduce vacuum resonance-enhanced multiphoton ionization (REMPI) with high-resolution Orbitrap Fourier transform mass spectrometry (FTMS) for analyzing silylated polar compounds. UV laser radiation at 248 nm sensitively and selectively targets aromatic constituents, while high-resolution mass spectrometry (HRMS) enables high-performance mass spectrometric detection. This workflow enhances the detection confidence of polar constituents by identifying unique isotopologue patterns, including at the isotopic fine structure (IFS) level, in analytical standards and complex bio-oils. A direct and derivatized gas chromatography (GC) procedure on a polar standard component mixture allowed us to explore the general ionization and detection characteristics of REMPI FTMS. HRMS enabled the examination of the complex isotopologue profiles, revealing distinct patterns for the CHOxSiy-class compounds. Particularly in complex mixtures, this isobaric/isonucleonic complexity exceeded the classical mass resolution capabilities of the employed Orbitrap D30 series and prompted the usage of prolonged transients via an external data acquisition system. This procedure substantially improved mass spectrometric results by recording the unreduced time-domain transient data for up to 2 s. Notably, the ability to distinguish diagnostic isotopic pairs, such as 12C/29Si vs 13C/28Si with a mass split of ∼3.79 mDa and 13C12C/28Si29Si vs 13C2/28Si2, with an approximate mass difference of ∼3.32 mDa, demonstrates a significant and expected performance improvement. Finally, we benchmark the GC HRMS methodology to identify silylated oxygenated and nitrogen-containing constituents in ultracomplex bio-oil samples. The presented approach of utilizing the silicon isotope pattern and unique isotopologue mass splits for increasing attribution confidence can be applied beyond bio-oils toward the general GC analyses of polar oxygenates.

PHYSICOCHEMICAL, BIOCHEMICAL AND SENSORY CHARACTERIZATION OF BEE BREAD FROM BURSA (TÜRKİYE) REGION

Bee bread, also known as perga, is a product created through anaerobic lactic fermentation, meticulously crafted by bees. Worker bees mix collected pollen with nectar and their specialized enzymes, then pack and store this nutrient-dense substance in honeycomb cells. Bee bread is highly esteemed as a valuable food source due to its rich protein content, antioxidants, phenolic compounds, vitamins, and minerals. Its health benefits have been increasingly recognized in recent years. This study aims to investigate the physical and chemical properties, as well as the aroma constituents, of bee bread samples sourced from Bursa and its surrounding areas. The analysis includes measurements of moisture content (17.89%), ash (2.53%), crude fat (9.16%), and crude protein (19.06%). Additionally, total phenolic content was determined 9.91 mg gallic acid equivalent per gram (mg GA/g), total flavonoid content at 0.32 mg quercetin equivalent per gram (mg QE/g), CUPRAC activity at 12.97 mg Trolox equivalent per gram (mg Trolox/g), and TEAC activity at 0.55 mM Trolox per milliliter (mg Trolox/mL). Aromatic compounds were identified and their percentage ratios determined using Solid Phase Microextraction (SPME) combined with Gas Chromatography-Mass Spectrometry (GC-MS). These findings align with previous research in the field, although significant variations among parameters are noted due to factors such as geographic location, climate, vegetation, collection time, and sample collection methodology.

An integrative pharmacology-based study on the efficacy and mechanism of essential oil of Chaihu Guizhi Decoction on influenza A virus induced pneumonia in mice

Ethnopharmacological relevanceChaihu Guizhi Decoction (CGD) has a long history of use in China for the treatment of influenza, which involves the use of a variety of aromatic herbs. Our previous studies have found that the contents of aromatic constituents in CGD affected the efficacy of treatment of influenza-infected mice, suggesting a clue that essential oil from CGD may play a relatively important role in ameliorating influenza induced pneumonia. Aim of the studyTo evaluate the anti-influenza potential of essential oil derived from Chaihu Guizhi Decoction (CGD-EO), to characterize and predict the key active components in CGD-EO, and to explore the mechanism of action of CGD-EO. Materials and methodsCGD-EO was obtained by steam distillation, and the components of the essential oil were characterized by gas chromatography-mass spectrometry (GC-MS) in conjunction with the retention index. The constituents absorbed into the blood of mice treated with CGD-EO were analyzed by headspace solid phase microextraction gas chromatography/mass spectrometry (HS-SPME-GC/MS). The potential anti-influenza active constituents and their possible action pathway were predicted by simulation using a network pharmacology approach. The protective effect of CGD-EO and its major components on H1N1/PR8-infected cells was determined using the CCK8 assay kit. Mice infected with influenza A virus H1N1/PR8 were administered different doses of CGD-EO orally and the body weights and lung weights were recorded. Mice with varying degrees of H1N1/PR8 infection were administered CGD-EO orally, and their daily weight, water consumption, and clinical indicators were recorded. Necropsies were conducted on days 3 and 5, during which lung weights were measured and lung tissues were preserved. Furthermore, the mRNA expression of the H1N1/PR8 virus and inflammatory factors in lung tissue was analyzed using RT-qPCR. Results(E)-cinnamaldehyde was the most abundant compound in the CGD-EO. The results of serum medicinal chemistry combined with network pharmacological analysis indicated that (E)-cinnamaldehyde and 3-phenyl-2-propenal may be potential active components of the CGD-EO anti-influenza, and may be involved in the NF-κB signalling pathway. In vitro studies have demonstrated that both CGD-EO and cinnamaldehyde exert a protective effect on MDCK cells infected with H1N1/PR8. In a 0.5 TCID50 H1N1/PR8-induced influenza model, mice treated with CGD-EO at a dose of 63.50 μg/kg exhibited a reduction in lung index, pathological lung lesions, and H1N1/PR8 viral gene levels. In addition, CGD-EO treatment was found to regulate the levels of inflammatory cytokines, including IL-6, TNF-α, and IFN-γ. Moreover, following three days of administration, an upregulation of NF-κB mRNA levels in mouse lung tissue was observed in response to CGD-EO treatment. ConclusionsThe findings of our study indicate CGD-EO exerts a protective effect against H1N1-induced cytopathic lesions in vitro and is capable of alleviating H1N1-induced pneumonitis in mice. Moreover, it appears to be more efficacious in the treatment of mild symptoms of H1N1 infection. Studies have demonstrated that CGD-EO has antiviral potential to attenuate influenza-induced lung injury by modulating inflammatory cytokines and NF-κB signalling pathways during the early stages of influenza infection. It is possible that (E)-cinnamaldehyde is a potential active ingredient in the anti-influenza efficacy of CGD-EO.

Rock-to-Pharma: Characterization of Shale Oil-Based Nonbiological Complex Drugs along the Production Process by High-Resolution Mass Spectrometry.

Antibiotic resistance has become a primary concern in medicine because of the overuse and misuse of classical pharmaceuticals. Recently, nonbiological complex drugs (NBCDs) have gained interest for their complex pharmacological profiles. Bituminosulfonates, which have lately been tentatively allocated toward NBCDs, are pharmacologically well-studied and show low potential in resistance development. However, molecular composition knowledge is limited. With this work, we present a comprehensive approach to investigate the manufacturing process of complex pharmaceuticals like bituminosulfonates on a molecular level via Fourier-transform ion cyclotron resonance mass spectrometry. The application of various hyphenations and ionization techniques comprehensively covers the entire mass and polarity range of the matrix, and the high sensitivity enables the identification of significant and minor chemical alterations caused by the multistep manufacturing process. The distillation of the shale crude oil eliminates highly aromatic PAH and PASH constituents. ESI(-) revealed strong PAH- and PASH-sulfonate formation after reacting the shale oil distillate with sulfuric acid. Increasing alkylation reduced the sulfonation yield, instead causing oligomerization side reactions, as observed by APPI analysis. Furthermore, multidimensional gas chromatography coupled with high-resolution mass spectrometry verified core structural motifs. With this work, we demonstrate the high potential of FT-ICR MS in NBCD process analysis. The results also give valuable information for future pharmacological investigations focusing on specific compound classes or properties.

Moringa oleifera flowers: insights into their aroma chemistry, anti-inflammatory, antioxidant, and enzyme inhibitory properties

BackgroundMoringa oleifera is a highly nutritious plant widely used in traditional medicine.ResultsThe aroma constituents present in the fresh flowers of M. oleifera versus the hydrodistilled oil and hexane extract were studied using GC-MS. Aldehydes were the major class detected in the fresh flowers (64.75%) with E-2-hexenal being the predominant component constituting > 50%. Alkane hydrocarbons, monoterpenes, and aldehydes constituted > 50% of the hydrodistilled oil, while alkane hydrocarbons exclusively constitute up to 65.48% of the hexane extract with heptacosane being the major component (46.2%). The cytotoxicity of the hexane extract was assessed on RAW 264.7 macrophages using the MTT assay which revealed no significant cytotoxicity at concentrations of 1 µg/mL and displayed IC50 value at 398.53 µg/mL as compared to celecoxib (anti-inflammatory drug) with IC50 value at 274.55 µg/ml. The hexane extract of Moringa flowers displayed good anti-inflammatory activity through suppression of NO, IL-6, and TNF-α in lipopolysaccharide-induced RAW 264.7 macrophages. The total phenolic and flavonoid content in the hexane extract was found to be 12.51 ± 0.28 mg GAE/g extract and 0.16 ± 0.01 mg RuE/g extract, respectively. It displayed moderate antioxidant activity as indicated by the in vitro DPPH, ABTS, CUPRAC, FRAP, and phosphomolybdenum (PBA) assays. No metal chelating properties were observed for the extract. The enzyme inhibitory potential of the hexane extract was evaluated on acetyl- and butyrylcholinesterases (for neuroprotective assessment), α-amylase and α-glucosidase (for antihyperglycemic assessment), and tyrosinase (for dermoprotective assessment) revealing promising results on cholinesterases, tyrosinase, and α-glucosidase.ConclusionOur findings suggested that M. oleifera leaves can be considered as a multidirectional ingredient for preparing functional applications.Graphical abstract

Metabolomics-guided discrimination of constituents in five commercial apple (Malus × domestica Borkh.) cultivars: Assessment of their antioxidant, neuroprotective, and antidiabetic activities for potential use as functional food

Apples (Malus × domestica Borkh.) are available in different cultivars, we investigated the similarities and differences in the chemical composition and biological activities of the extracted apple oils by hydrodistillation and hexane extraction. The aroma constituents obtained by hydrodistillation and n-hexane extraction of five commercial Egyptian apple cultivars namely Pink Lady (Cripps pink), Red Delicious, Ambrosia, Golden Delicious, and Granny Smith were investigated by Gas chromatography-mass spectrometry (GC-MS). The total phenolic (TPC) and total flavonoid contents (TFC), in vitro antioxidant analysis, and enzyme inhibition assays were performed. Results showed that TPC and TFC were the highest in the hexane extract of pink ladies with values of 12.42 (mg GAE/g FW) and 1.35 (mg RE/g FW), respectively. Similarly, pink lady hexane extract showed the highest efficacy in antioxidant assays like 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS), Cupric reducing antioxidant capacity (CUPRAC), ferric reducing antioxidant power (FRAP), metal chelation, and phosphomolybdenum tests with values of 25.21 mg TE/g, 39.82 mg TE/g, 19.27 mg TE/g, 28.16 mg EDTAE/g, and 1.36 mmol TE/g, respectively. Assessments of enzyme inhibition potential of the hexane extracts of the five cultivars on acetylcholinesterase (AChE) showed efficacy for ambrosia only with inhibition value at 2.53 mg GALAE/g. All other cultivars showed comparable efficacies in inhibiting tyrosinase, amylase, and glucosidase enzymes. Significant differences were observed in the chemical composition of the five apple cultivars which were reflected by differences in their antioxidant and enzyme inhibition capacities. Results of biological studies were further confirmed with in silico investigations.

Sensomics-assisted analysis unravels the formation of the Fungus Aroma of Fu Brick Tea

Fu Brick Tea (FBT) is characterized by Fungus Aroma (FA), which determines the quality of FBT products. However, the aroma constituents and their interactive mechanism for FA remain unclear. In this study, the FBT sample with the optimal FA characteristics was selected from 29 FBTs. Then, 19 components with OAV ≥ 1 were identified as the odorants involved in the FA formation. The aroma recombination test suggested that the FA was potentially produced by the synergistic interplay among the 15 key odorants, including (E,E)-2,4-heptadienal, (E,E)-2,4-nonadienal, (E)-2-nonenal, (E,Z)-2,6-nonadienal, (E)-2-octenal, (E)-β-ionone, 4-ketoisophorone, dihydroactinidiolide, (E)-β-damascenone, 1-octen-3-ol, linalool, geraniol, heptanal, hexanal, and phenylacetaldehyde. And, the synergistic effects between them were preliminarily studied by aroma omissions, such as modulatory effects, masking effects, compensatory effects, and novelty effects, ultimately contributing to the FA. In all, this work helps us better understand the formation of the FA and provides a basis for the improvement of FBT production technology.

RSM optimization of fermentation technology of yellow wine produced from Millets rice (containing Daylily and Agaricus blazei Murr) and analysis of volatile aroma constituents and amino acid contents by GC–MS and HPLC

The fermentation process was carried out with varied input variables, and all the models showed significant p-values for interaction of variance (<0.05). Millet rice yellow wine with ethanol yield of 15.68%, v/v was produced at an optimized temperature of 32 °C, yeast addition quantity of 9%, and time of 41 days. The volatile compounds in millet rice wine were analyzed by gas chromatography coupled with mass spectrometry (GC/MS). Amino acid components in yellow wines were analyzed by high performance liquid chromatography (HPLC). Ten, twelve and sixteen volatile compounds were detected in wines in fermentation time of 41, 55 and 70 days, respectively. HPLC shows that the content of amino acids in rice wine is not only the highest, but also has 20 kinds, including 8 kinds of essential amino acids for human body. The difference in volatile components and amino acids composition greatly contribute to the flavor of the wine.

Characterization and correlation analysis of microbial flora and flavor profile of stinky acid, a Chinese traditional fermented condiment

To explore the microbial diversity and flavor profiles of stinky acid, we utilized high-throughput sequencing, culture-based techniques, and bionic E-sensory technologies. The results revealed a significant correlation between the acidity levels of stinky acid and the richness of its microbial community. Ten core bacterial genera and three core fungal genera exhibited ubiquity across all stinky acid samples. Through E-nose analysis, it was found that sulfides constituted the principal odor compounds responsible for stinky acid's distinct aroma. Further insights arose from the correlation analysis, indicating the potential contribution of Debaryomyces yeast to the sour taste profile. Meanwhile, three genera—Rhizopus and Thermoascus and Companilactobacillus—were identified as contributors to aromatic constituents. Interestingly, the findings indicated that Rhizopus and Thermoascus could reduce the intensity of the pungent odor of stinky acid. In summary, this investigation's outcomes offer new insights into the complex bacterial diversity of stinky acid.

Aroma Profile of Apple Spirits Fermented With non-Saccharomyces Yeasts and Their Dynamic Changes During Maturation

Recently, non-Saccharomyces yeasts have gained considerable attention as a novel strategy to enhance the aroma diversity of alcoholic beverages. This study explores the effect of sequential fermentations involving Lachancea thermotolerans and Torulaspora delbrueckii on the aroma profile of apple spirits. Additionally, the influence of time, temperature, and alcohol content on the volatile composition during the maturation of distillates was described. The results revealed that distillates obtained from mixed cultures exhibited improved aroma complexity, primarily due to increased ester production. Torulaspora delbrueckii positively influenced the synthesis of 2-phenethyl acetate, diethyl succinate, and hexyl acetate. Lachancea thermotolerans promoted the formation of ethyl lactate, ethyl myristate, and ethyl phenylacetate while reducing the concentration of higher alcohols. During maturation, changes in aroma constituents were observed. In general, the concentration of the investigated volatile compounds tends to decrease during maturation, with this trend being strongly related to the alcohol content of the distillates. Temperature did not affect the variations of methanol, acetaldehyde, 1-propanol, 2-butanol, 2-methyl-1-butanol, cis-2-hexen-1-ol, and diethyl succinate. Regarding esters, increases were observed in the concentration of ethyl octanoate, ethyl myristate, and, under certain circumstances, ethyl acetate and isoamyl acetate. No correlation was found between changes in acetaldehyde and the conditions tested.

Profiling volatile compounds in fresh leaves of 22 major oolong tea germplasm cultivated in Fujian of China

Tea is highly esteemed by consumers due to its distinct aroma and the abundance of nutrients that contribute to human well-being. While volatile compounds in fresh tea leaves serve as the essential foundation for tea aroma, the understanding of cultivar-specific aroma constituents and their genetic regulation remains a research gap. In this study, we extracted and profiled the volatile compounds in fresh leaves from 22 major oolong tea cultivars using gas chromatography-mass spectrometry. A total of 140 volatile compounds were identified, of which 61 were consistently found in all tea cultivars. The volatile profiles of the 22 tea cultivars exhibited considerable dissimilarity, with several distinct cultivar-specific volatiles identified. Subsequent analysis of nonadditive volatiles in tea hybrids revealed a noteworthy positive mid-parent heterosis (MPH) in ‘Mingke 1’ (also known as ‘Jinguanyin’) and ‘Huangmeigui’. Comprehensive heterosis across various volatile compounds was also documented. Our study elucidated the composition of volatile compounds in the fresh leaves from the major oolong tea cultivars and provided an extensive exploration of volatile heterosis in tea plants. These cultivar-specific volatile variations will offer essential insights for enhancing the genetic aspects of tea aroma flavor and deepen our understanding of the molecular mechanisms underlying volatile compound formation in fresh tea leaves.

Investigation of lignin substructures participating in self-assembly for the synthesis of monodisperse lignin spherical particles

The intricate structure of lignin, characterized by a mix of hydrophilic components and hydrophobic structures from its aliphatic and aromatic constituents, poses challenges in creating monodisperse particles. This is due to the need for precise modulation of self-assembly kinetics. Herein, we explore a correlation between the substructure of lignin and its capacity for self-assembly. We have conducted an in-depth investigation into the interactions between hydrophilic groups, such as phenolic and aromatic-OH, and monolignols with interunit linkages that are involved in the formation of lignin particles (LPs). A high degree of hydrophilicity with a condensed structure is crucial for high supersaturation levels, which in turn determines the growth phase and leads to small LPs. An approach based on tailoring the supersaturation level which is contingent on the structural characteristics of extracted organosolv lignin was used to obtain remarkably uniform LPs with mean diameters of approximately 230 and 480 nm. The results of this study have the potential to serve as a foundation for the preparation of monodisperse LPs derived from various lignin sources as well as for the development of methods to extract lignin containing a specific chemical substructure.

Insight into the aroma quality of ‘Callista’ cultivar of hop (Humulus lupulus L.): impact of harvest timing, year, and location

Hops (Humulus lupulus L.) are essential ingredients in brewing, contributing to beer’s flavor, aroma, and stability. This study pioneers an in-depth analysis of the 'Callista' cultivar, aiming to unravel how harvest timing, annual variations, and cultivation location synergistically influence its molecular profile, sensory perception, and biochemistry. Leveraging high-performance liquid chromatography and gas chromatography-mass spectrometry-olfactometry, we identified significant year-to-year and location-based fluctuations in bitter acids—the quintessential aroma constituents in hops. Our comprehensive aroma profiling discerned 55 volatile compounds, marking the first-ever sensory detection of 2-butanone in hops, with its presence showing remarkable interannual variability. This study showed significant differences among the three years tested, whereas hops were perceived “fruitier” and more “citrusy” in 2021, even though the bitter acid and aroma analysis showed that 2022 sticks out due to extremely high lupulone values up to 10% dry cone weight and 78% β-myrcene in the oil fraction compared to 60% and 45% in 2020 and 2021, respectively. Molecular analysis of key enzymes involved in hop aroma biosynthesis revealed no significant associations with location, but a strong diurnal pattern for all genes. The results indicated that especially the hot temperatures of 2022 may have induced significant changes of cone quality, while 2021 was more interesting from the sensory evaluations, which may justify the usage of viticultural terms such as “vintage” for hop marketing. These findings contribute to a better understanding of the factors influencing hop aroma and quality.

Recent Advancement in Agarwood Induction Technology: A Comprehensive Review for the Transformation of Artificial Agar Resin Induction Methods

Agarwood is a high valued resinous wood containing aromatic constituents of sesquiterpenes and phenyl-ethylchromones. They are typically found in the wood tissue of Thymalaeaceae family trees such as Aquilaria and Gyrinops species once they have been physically or chemically damaged or diseased by microbial pathogens. However, the natural occurrence based agarwood production is inadequate to fulfill the worldwide market demand as it never reach to the potential yield. As a result, recent advancements in artificial agarwood induction technology have led to the efficient production of agarwood resin, surpassing conventional methods. These technologies include mechanical, biological, and chemical methods, as well as combinations of these techniques such as fungal inoculation, nailing, drilling, partly trunk pruning, aeration method, agar-wit, C-A kits, Agar-sit, Bottle dipping, ChemJet, Pinhole infusion, Automated transfusion, Agar-Bit and Bamboo stick method. While interdisciplinary approaches have pros and cons, chemical inducers have shown rapid invasion inside particular tree species trunks to produce superior agarwood resin at consistent rate. Therefore, diverse forms of inducers can be utilized to develop this finest fragrance resinous wood in cultivated trees within a short period of time compared to the natural approach and almost similar in the quality compared to the natural agarwood formations. The objective of this review paper was to presents a comprehensive collection of agarwood resin inducing methods and their potential to enhance the total production and the quality of agarwood in the final harvest. The application of these techniques has significant implications to the agarwood industry as it seeks to meet the growing global demand for this highly sought-after and valuable product leading to a high profitable business. Therefore, this review article serves as a valuable collection of resource for the researchers and industry professionals who are ambitious to develop their agarwood industry to a new level.

Chemical Composition, Preliminary Toxicity, and Antioxidant Potential of Piper marginatum Sensu Lato Essential Oils and Molecular Modeling Study.

The essential oils (OEs) of the leaves, stems, and spikes of P. marginatum were obtained by hydrodistillation, steam distillation, and simultaneous extraction. The chemical constituents were identified and quantified by GC/MS and GC-FID. The preliminary biological activity was determined by assessing the toxicity of the samples to Artemia salina Leach larvae and calculating the mortality rate and lethal concentration (LC50). The antioxidant activity of the EOs was determined by the DPPH radical scavenging method. Molecular modeling was performed using molecular docking and molecular dynamics, with acetylcholinesterase being the molecular target. The OES yields ranged from 1.49% to 1.83%. The EOs and aromatic constituents of P. marginatum are characterized by the high contents of (E)-isoosmorhizole (19.4-32.9%), 2-methoxy-4,5-methylenedioxypropiophenone (9.0-19.9%), isoosmorhizole (1.6-24.5%), and 2-methoxy-4,5-methylenedioxypropiophenone isomer (1.6-14.3%). The antioxidant potential was significant in the OE of the leaves and stems of P. marginatum extracted by SD in November (84.9 ± 4.0 mg TE·mL-1) and the OEs of the leaves extracted by HD in March (126.8 ± 12.3 mg TE·mL-1). Regarding the preliminary toxicity, the OEs of Pm-SD-L-St-Nov and Pm-HD-L-St-Nov had mortality higher than 80% in concentrations of 25 µg·mL-1. This in silico study on essential oils elucidated the potential mechanism of interaction of the main compounds, which may serve as a basis for advances in this line of research.

Resonance enhanced multiphoton ionization detection of aromatics formation in fuel-rich flames

Polycyclic aromatic hydrocarbons (PAHs) are formed in fuel-rich and sooting hydrocarbon flames. These compounds and smaller aromatic flame constituents, such as benzene, toluene and naphthalene can be detected by flame-sampling molecular beam mass spectrometry (MBMS). They are readily ionized by photoionization with UV light, either in resonant or non-resonant ionization processes. The multiphoton ionization of benzene, toluene, and styrene with MBMS detection was investigated as a function of laser power and wavelength and the quantitative relation between ion signal and mole fractions in the flames was established. These measurements were prerequisites for the measurement of quantitative mole fraction profiles of these species in flames of various fuels. In addition, the measurements provide relative mole fraction profiles of various other aromatic flame species. The results are compared to measurements of aromatics in butadiene, propyne, and allene flames by single-photon ionization with vacuum ultraviolet radiation from a synchrotron source and other literature data.

Urate oxidase treatment increases the quality of autumn Yellowish Yinghong 9 black tea

Microbes can be used to improve the quality of fermented beverages and food. Colletotrichum camelliae is one of the most dominant fungi associated with tea leaves. In the present study, black tea produced from the autumn leaves of Yellowish Yinghong 9 was treated with C. camelliae urate oxidase (CcUOX) to determine whether this treatment could improve tea quality. The effects of recombinant CcUOX on several black tea quality parameters were assessed, such as liquor color, aroma, and levels of theabrownins, thearubigins, total polyphenols, catechins, caffeine, xanthine, and hypoxanthine. CcUOX treatment significantly affected the aroma composition and volatile compound profiles. Specifically, volatiles in the benzenoid/phenylpropanoid, fatty acid metabolism, and amino acid pathways were increased in CcUOX-treated black tea, whereas levels of volatiles in the terpineol and carotenoid pathways were reduced. This suggested that the balance of aroma constituents in Yellowish Yinghong 9 black tea was affected by treatment with CcUOX. The present study provides evidence that pre-treatment of black tea with a single enzyme from a common tea-associated microbe could significantly improve autumn tea quality, validating this method for use in further studies of tea improvement.

Impact of frying methods on colours, morphological properties, and aroma compounds of arrowhead (Sagittaria latifolia) corm chips

Arrowhead is a starchy vegetable with a unique taste and many health promoting effects. To diversify the usage and increase the consumption of arrowhead, the effects of different frying methods on the morphology and aroma compounds of arrowhead corm chips were studied. The analysis of aroma compounds by accelerated solvent extraction coupled with high-vacuum flavour extraction analysis (ASE-HVFEA), gas chromatography-mass spectrometry (GC-MS), and gas chromatography-olfactometry (GC-O) of deep- and air-fried arrowhead corm chips was conducted. The aim was to understand the variability and abundance of aroma compounds between deep- and air-fried arrowhead chips. In addition, the colours and morphological characteristics of the corm chips were also studied. Twenty-three aroma compounds were identified in the differently fried chips. The predominant aroma compounds were the Strecker-aldehydes, in which 2-methylbutanal, (E)-2-heptenal, hexanal, and (E,E)-2,-4-decadienal were identified as the major aroma constituents of the fried chips. This was followed by the pyrazines. Results of the odour activity values (OAVs) revealed significant (p &lt; 0.05) differences in the aroma profiles of the differently fried chips. Deep-fried chips produced more potency for the baked-like, 2-3-diethyl-5-methylpyrazine, potato-like, methional, deep-fried, (E,E)-2,4-decadienal, roasty, 2-ethyl-3,5-dimethylpyrazine, malty, and 2-methylbutanal. However, air-fried chips exhibited similar but lower potency for the same compounds. Whilst there was no significant (p ≥ 0.05) difference in the external appearance of the differently fried chips, deep-frying significantly (p &lt; 0.05) altered the cell walls of the deep-fried chips more than the air-fried chips. These results would serve as a guidance for aroma flavour evaluation, improvement, and quality control during oil- and air-frying of chips.

Evaluation of Phenolic and Aromatic Compound of Placenta Three Cocoa Varieties (Theobroma cacao L) Cultivated in Côte d’Ivoire

Cocoa placenta obtained after the removal of beans is a huge cocoa by-product usually regarded as waste by farmers. Cocoa placenta from three cocoa varieties: forastero, criollo and national were investigated to provide more comprehensive informations on aroma and phenolic compounds present in these cocoa placenta. For this, these 3 cocoa placenta widely produced in Côte d’Ivoire were oven-dried (50°C/3 days) after fermentation before analysis of phenolics and aromatics compounds. A total of 14 phenolic compounds were identified in all cocoa placenta samples with the highest amount observed in criollo (212.99 mg/g). Kaempferol pentosyldihexoside was found as the major phenolic substance in all the samples with an important amount in criollo (54.63 mg/g). According to the findings of compounds volatiles profile, a total of 48, 55 and 60 aroma constituents with variable groups including esters, alcohols, aldehydes, terpenes, furans, acids, volatile phenols, hydrocarbons, and ketones were detected in criollo, forastero and national, respectively. The highest total amount was detected in national placenta (406.76 mg/kg). 2-hexanol (73.56 mg/kg), 3-Methyl-3-pentanol (19.96 mg/kg), Methoxy-1-butanol (11.75 mg/kg) was the prominent volatile substance in all cocoa placenta. The results of the present study clearly demonstrate that cocoa placenta is a potential by-product that could be used in animal feed or human food formulation in order to be valued in the dietetic field.