Analysis of volatile compounds from three species of Atractylodes by Gas Chromatography-Mass Spectrometry

A total of 99 different volatile compounds were detected through Gas Chromatography-Mass Spectrometry (GC-MS) from three species of Atractylodes, namely Atractylodes lancea, Atractylodes japonica, and Atractylodes chinensis. Thirteen-volatile flavor compounds i.e., acid, alcohol, aldehyde, alkane, alkene, alkyne, ester, ketone, monoterpene, oxygenated monoterpene, sesquiterpene, oxygenated sesquiterpene, and oxygenated triterpenoid detected from different species of Atractylodes. It was observed that all the species contained 38 common compounds, while A. lancea contained 7 unique compounds, A. japonica has 4 unique compounds, and A. chinensis hold 6 compounds not detected in the other extracts. In addition, essential oils from A. lancea and A. japonica possessed 11 compounds in common, and A. lancea and A. chinensis possessed 19 compounds in common. The remaining 14 compounds were detected only in A. japonica and A. chinensis. The total content of all components in the species was comparable, with 82.528%, 81.766%, and 81.799% of volatile components being detected for A. lancea, A. japonica, and A. chinensis, respectively. Curzerene was found to be the most predominant compound in both A. lancea (14.1%) and A. chinensis (16.7%), while murolan-3,9(11)-diene-10-peroxy was found predominantly in A. japonica (16.8%). The present study suggests that the identified volatile compounds may possess important biological properties, and could be suitable for application in both oriental medicines and the pharmaceutical industry.

The Effects of Post-Harvest Treatments on the Quality of Agastache aurantiaca Edible Flowers

Agastache spp. are used as ornamental plants for their pleasant aroma and the different colors of flowers. Nowadays, their edible flowers have become attractive for their nutraceutical properties. Post-harvest treatment appears as a crucial point to avoid impairment of the nutraceutical compounds and aroma, so different treatments were tested to analyze their effect on the bioactive metabolites and volatilome. Results indicated that freeze-drying was the best solution to prolong the shelf life of these flowers. The use of high temperatures (50, 60, 70 °C) led to altered the composition of antioxidant compounds (phenolic compounds, flavonoids, anthocyanins, carotenoids). Air-drying at 30 °C was a reasonable method, even though time consuming. Concerning the aroma profile, all samples were dominated by oxygenated monoterpene compounds. Pulegone was the main or one of the major constituents of all samples together with p-menthone. Gas Chromatography-Mass Spectrometry results showed a correlation between the temperature and the number of identified compounds. Both fresh and freeze-dried samples evidenced a lesser number (10 and 19, respectively); when the temperature raised, the number of identified constituents increased. Statistical analyses highlighted significant differences between almost all aromatic compounds, even if both Principal Component and Hierarchical Cluster analyses differed at 60 and 70 °C and from the other treatments.

Effectiveness of recombinant Escherichia coli on the production of (R)-(+)-perillyl alcohol

Background (R)-(+)-perillyl alcohol is a naturally oxygenated monoterpene widely used as the natural flavor additives, insecticides, jet fuels and anti-cancer therapies. It was also readily available monoterpene precursors. However, this natural product is present at low concentrations from plant sources which are not economically viable. Therefore, alternative microbial production methods are rapidly emerging as an attractive alternative to make (R)-(+)-perillyl alcohol production more sustainable and environmentally friendly. Results We engineered Escherichia coli to possess a heterologous mevalonate (MVA) pathway, including limonene synthase, P-cymene monoxygenase hydroxylase and P-cymene monoxygenase reductase for the production of (R)-(+)-perillyl alcohol. The concentration of (R)-(+)-limonene (the monoterpene precursor to (R)-(+)-perillyl alcohol) reached 45 mg/L from glucose. Enhanced (R)-(+)-perillyl alcohol production was therefore achieved. The strain produced (R)-(+)-perillyl alcohol at a titer of 87 mg/L and a yield of 1.5 mg/g glucose in a 5 L bioreactor fed batch system. Conclusions These datas highlight the efficient production of (R)-(+)-perillyl alcohol through the mevalonate pathway from glucose. This method serves as a platform for the future production of other monoterpenes.

Oligomer and highly oxygenated organic molecule formation from oxidation of oxygenated monoterpenes emitted by California sage plants

Plants emit a diverse range of biogenic volatile organic compounds (BVOCs) whose oxidation leads to secondary organic aerosol (SOA) formation. The majority of studies of biogenic SOA have focused on single or simple multicomponent BVOC mixtures thought to be representative of Northern hemispheric deciduous or mixed forest conditions. Gaps remain in our understanding of SOA formation from complex mixtures of real plant emissions in other environments. Towards the goal of understanding SOA in other regions, we conducted the first comprehensive study of SOA from oxygenated monoterpenes. These are the dominant emissions from the most common plant species in southern California's coastal sage ecosystem: black sage (Salvia mellifera) and California sagebrush (Artemisia californica). Emissions from sage plants, as well as single compounds representing their major emissions (camphor, camphene and eucalyptol), were oxidised in an Aerodyne potential aerosol mass oxidation flow reactor (PAM-OFR). The chemical composition of SOA was characterised using a high-resolution time-of-flight iodide-anion chemical-ionisation mass spectrometer equipped with a Filter Inlet for Gases and AEROsols (FIGAERO-I-HR-ToF-CIMS) under low- and medium-NOx conditions. SOA from oxygenated monoterpenes showed a higher-order oligomer content and a greater presence of highly oxygenated organic molecules (HOMs) than non-oxygenated monoterpenes, with HOM contributing 27 %–47 % and 12 %–14 % of SOA product signal from oxygenated and non-oxygenated monoterpenes respectively. This study highlights the potential importance of oxygenated monoterpene emissions for SOA formation in woody shrub ecosystems.

The effect of drying time on the yield and the chemical composition of essential oil and dissolved oil in hydrolat from aerial parts of Moroccan Thymbra capitata (L.) Cav

<p>The present research aimed to study the effect of drying time on the yield and chemical composition of essential oil (EO) and dissolved oil in hydrolat (HY) from aerial parts of Moroccan <em>Thymbra capitata</em> (L.) Cav. Drying of plant material was carried out naturally in the shade of a draughty place at room temperature (25–27°C). A series of 10 plant samples were subjected to hydrodistillation using a Clevenger-type apparatus. The results indicated that the yield of EO increased with drying time to reach the highest value on the 8^th drying day (2.7%), while the yield of HY has not undergone an apparent variation (0.2% – 0.6%). Based on the GC-MS analyses, EO was composed mainly of the phenolic monoterpene carvacrol (80.10%–92.27%) along with its biogenetic precursors' monoterpene hydrocarbons in a 1.02%–4.81% range <em>p</em>-cymene and 0.24% -1.86 % <em>γ</em>-terpinene. Other essential components occurring in minor quantity were sesquiterpene hydrocarbon <em>a</em>-humulene (2.58% – 4.67%) and oxygenated monoterpene linalool (0.80% –2.06%). At the same time, HY was constituted mainly of carvacrol (94.67–98.42%) along with <em>a</em>-humulene at much lower concentrations (0.31%–0.86%) and the oxygenated derivative acetovanillone acetate (0.2%–1.80%). On the other hand, the highest concentration of carvacrol in EO was reached on the 5^th day of the drying plant process (92.27%), while the HY recovered on the 7^th day has shown carvacrol in its highest concentration (98.42%).</p>

Essential Oil Compositions of Aframomum danielli Seed (Ataiko)

Background: Differentiation in oil quality and the volatile component of essential oils (EOs) is associated with climatic conditions, the geographical location of collection sites and other ecological and genetic factors defining its chemotypes. Objective: Hence this study was aimed at characterizing volatile constituents of Aframomum danielli seed collected in Choba, Port Harcourt in Rivers State, South-South region of Nigeria. Methods: Essential oils (EOs) were analyzed using gas chromatography–flame ionization detector (GC-FID). Results: A total of forty-two EO (99.96%) constituents were identified, monoterpenes were 32 (99.93%) and sesquiterpenes: 10 (0.03%) No oxygenated sesquiterpenes were detected. Oxygenated monoterpene was higher consisting of 18 EO compounds; 66.94% while monoterpene hydrocarbons comprised of 14 EO compounds; 32.99%. Chemical constituents in the EO include: 1,8- cineole (50.95%), β-pinene (11.79%) –terpineol (9.15%), γ –terpinene (7.45%), Sabinene (6.03%), - pinene (3.41%), α –terpinenly acetate (3.38%), terpinene-4-of(2.44%) and α-thujene (2.11%). Conclusion: Aframomum danielli from this geographical location could serve as a rich source of 1,8- cineole.

Oligomer and highly oxygenated organic molecule formation from oxidation of oxygenated monoterpenes emitted by California sage plants

Plants emit a diverse range of biogenic volatile organic compounds (BVOC) whose oxidation leads to secondary organic aerosol (SOA) formation. The majority of studies of biogenic SOA have focused on single or simple multi-component BVOC mixtures thought to be representative of Northern Hemispheric deciduous or mixed forest conditions. Gaps remain in our understanding of SOA formation from complex mixtures of real plant emissions in other environments. Towards the goal of understanding SOA in other regions, we conducted the first comprehensive study of SOA from oxygenated monoterpenes. These are the dominant emissions from the most common plant species in southern California’s coastal sage ecosystem: black sage (Salvia mellifera) and California sagebrush (Artemisia californica). Emissions from sage plants, and single compounds representing their major emissions (camphor, camphene and eucalyptol), were oxidised in an Aerodyne potential aerosol mass oxidation flow reactor (PAM-OFR). The chemical composition of SOA was characterised using a high-resolution time-of-flight iodide-anion chemical-ionization mass spectrometer equipped with a Filter Inlet for Gases and AEROsols (FIGAERO-I-HR-ToF-CIMS) under low and medium-NOx conditions. SOA from oxygenated monoterpenes showed higher order oligomer content and a greater presence of highly oxygenated organic molecules (HOM) than non-oxygenated monoterpenes, with HOM contributing 27–47 % and 12–14 % of SOA product signal from oxygenated and non-oxygenated monoterpenes, respectively. This study highlights the potential importance of oxygenated monoterpene emissions for SOA formation in woody shrub ecosystems.

Effectiveness of recombinant Escherichia coli on the production of (R)-(+)-perillyl alcohol

Background : ( R )-(+)-perillyl alcohol is a naturally oxygenated monoterpene that is produced in perilla leaves, citrus, lemon and lavender. Perillyl alcohols have many uses, including as natural flavor additives, insecticides, jet fuels and anti-cancer therapies. The bioconversion of readily available monoterpene precursors, such as ( R )-(+)-limonene, are recognized as valuable oxygenated derivatives. However, as this natural product is present at low concentrations in plant oils, alternative microbial production methods are required for its extraction from natural plant sources. Results : We engineered Escherichia coli to possess a heterologous mevalonate (MVA) pathway, including limonene synthase , P-cymene monoxygenase hydroxylase and P-cymene monoxygenase reductase for the production of ( R )-(+)-perillyl alcohol. The concentration of ( R )-(+)-limonene (the monoterpene precursor to ( R )-(+)-perillyl alcohol) reached 27.3 mg/L from glucose. Enhanced ( R )-(+)-perillyl alcohol production was therefore achieved. The strain produced ( R )-(+)-perillyl alcohol at a titer of 45.7 mg/L in a 5 L bioreactor fed batch system. Conclusions : These data highlight the efficient production of ( R )-(+)-perillyl alcohol through the mevalonate pathway from glucose. This method serves as a platform for the future production of other monoterpenes.

Effectiveness of recombinant Escherichia coli for the production of (R)-(+)-perillyl alcohol 

Background:(R)-(+)-perillyl alcohol is a naturally oxygenated monoterpene that is produced in perilla leaves, citrus, lemon and lavender. Perillyl alcohols have many uses, including natural flavor additives, insecticides, jet fuels and anti-cancer therapies. The bioconversion of readily available monoterpene precursors, such as (R)-(+)-limonene are recognized as valuable oxygenated derivatives. However, as this natural product is present at low concentrations in plant oils, alternative microbial production methods are required for its extraction from natural plant sources. Results:In this study, we engineered Escherichia coli to possess a heterologous mevalonate (MVA) pathway, including limonene synthase, P-cymene monoxygenase hydroxylase and P-cymene monoxygenase reductase for the production of (R)-(+)-perillyl alcohol. The concentration of (R)-(+)-limonene (the monoterpene precursor to (R)-(+)-perillyl alcohol) reached 27.3 mg/L from glucose. Enhanced (R)-(+)-perillyl alcohol production was therefore achieved. The strain produced (R)-(+)-perillyl alcohol at a titer of 45.7 mg/L in a 5 L bioreactor fed batch system. Conclusions:These data highlight the efficient production of (R)-(+)-perillyl alcohol through microbial fermentation. This can serve as a platform for the future production of other monoterpenes.

Composition and Anti-inflammatory Effect of the Common Myrtle’s (Myrtus communis L.) Essential Oil Growing Wild in Algeria

This study was designed to evaluate the chemical composition and anti-inflammatory activity of the common myrtle essential oil (Myrtus communis L.). The essential oil composition of Myrtus communis L. extracted by steam distillation was characterized by a high oxygenated monoterpene fraction (80.9%). The major components were myrtenyl acetate (38.7%), eucalyptol (12.7%), α-pinene (13.7%), and linalool (7.00%). The chemical profile of this essential oil allows us to classify it as myrtényle acétate/α-pinène chemotype, but with atypical proportions, related to the harvesting area. In the carrageenan-induced paw edema, five different groups were established and the essential oil was administered orally in three different doses. The common myrtle essential oil (100 mg/kg) was able to reduce the paw edema, with a comparable effect to that observed with Diclofenac (positive control). This is the first report to demonstrate a significant anti-inflammatory activity of Algerian common myrtle essential oil.