Sesquiterpenes Β-caryophyllene Research Articles

Volatile and non-volatile metabolite profiling of under-explored crop Piper colubrinum link. With chromatography mass spectrometry approach and its biochemical diversity from medicinally valued Piper species

Piper colubrinum Link. is an underexplored crop regarding its metabolites and therapeutic attributes. Current study aimed to identify the possible volatile and non-volatile metabolites of P. colubrinum fruit and studied its metabolite diversity with medicinally valued Piper species viz. P. nigrum L., P. longum L. and P. chaba Hunter. The volatile constituents of P. colubrinum essential oil by GC–MS revealed the presence of sesquiterpenes as the major contribution. The sesquiterpenes α-muurolol (12.5 %) and β-caryophyllene (11.3 %) were the predominant volatile components. Few aliphatic compounds like n-heptadecane and trace amounts of monoterpenes (α- and β-pinene and α-terpineol) were also identified from this crop. The fatty acid profiling by GC–MS revealed mainly oleic acid (41.3 %) followed by palmitic and linoleic acids. HPLC analysis demonstrated that the major pungent alkaloid piperine was found to be trace (0.04 %) in P. colubrinum. The LC-QTOF-MS/MS profiling of the chloroform extract of the P. colubrinum revealed the presence of non-volatile constituents including phenolic and alkaloid compounds. Ferulic acid, rosmarinic acid, salicylic acid, kaempferol-5-glucoside, 5-methoxysalicylic acid, apigenin-7-galactoside, kaempferide-3-glucoside, luteolin, kaempferol, apigenin and scutellarein-4′-methyl ether were the phenolic compounds whereas piperlonguminine was the alkaloid compound identified. Finally, the biochemical parameters of this crop were compared with that of P. nigrum, P. longum and P. chaba and average linkage cluster dendrogram revealed that P. colubrinum was biochemically distinct from other three Piper species.

Potential Anti-Infectious Activity of Essential Oil Chemotypes of Lippia origanoides Kunth on Antibiotic-Resistant Staphylococcus aureus Strains.

Staphylococcus aureus infections are prevalent in healthcare and community environments. Methicillin-resistant S. aureus is catalogued as a superbug of high priority among the pathogens. This Gram-positive coccus can form biofilms and produce toxins, leading to persistent infection and antibiotic resistance. Limited effective antibiotics have encouraged the development of innovative strategies, with a particular emphasis on resistance mechanisms and/or virulence factors. Medicinal aromatic plants have emerged as promising alternative sources. This study investigated the antimicrobial, antibiofilm, and antihemolysis properties of three different chemotypes of Lippia origanoides essential oil (EO) against susceptible and drug-resistant S. aureus strains. The chemical composition of the EO was analyzed using GC-MS, revealing high monoterpene concentrations, with carvacrol and thymol as the major components in two of the chemotypes. The third chemotype consisted mainly of the sesquiterpene β-caryophyllene. The MIC values for the two monoterpene chemotypes ranged from 62.5 to 500 µg/mL for all strains, whereas the sesquiterpene chemotype showed activity against seven strains at concentrations of 125-500 µg/mL, which is the first report of its anti-S. aureus activity. The phenolic chemotypes inhibited biofilm formation in seven S. aureus strains, whereas the sesquiterpene chemotype only inhibited biofilm formation in four strains. In addition, phenolic chemotypes displayed antihemolysis activity, with IC50 values ranging from 58.9 ± 3.8 to 128.3 ± 9.2 µg/mL. Our study highlights the importance of L. origanoides EO from the Yucatan Peninsula, which has the potential for the development of anti-S. aureus agents.

ANTIMICROBIAL AND CYTOTOXIC ACTIVITIES OF ESSENTIAL OIL FROM THE AERIAL PARTS OF PULICARIA DYSENTERICA (L.) BERNH. (ASTERACEAE)

The chemical composition of Pulicaria dysenterica(L.) Bernh. aerial parts essential oil (EO), growing wildin Bosnia and Herzegovina, was presented in the study. In addition to the EO composition, antimicrobial and cytotoxic activities were also tested. The aerial parts of P. dysentericacontained 0.3% of yellow, liquid, fragrant EO. The 51 components identified accounted for 81.09% of the oil. The EO was characterized by the presence of a high concentration of oxygenated sesquiterpenes 51.83% while oxygenated monoterpenes constituted 15.57%, sesquiterpene hydrocarbons 9.32% and non-terpene compounds presented 4.37% of the EO. The dominant compounds were the sesquiterpenes caryophyllene oxide, (E)-nerolidol, β-caryophyllene and monoterpene nerol. The antimicrobial activity of EO was tested against selected ATCC strains of microorganisms, the bacteria Staphylococcus aureus, Pseudomonas aeruginosaand Escherichia coli, and the fungus Candida albicans. The results showed that the investigated EO inhibited the growth of all selected ATCC strains of microorganisms. The best result was obtained against Escherichia colibacteria with MIC value of 1 mgmL-1. The cytotoxicity of EO was measured against the HeLa cell line using the MTT method with IC50of 188.52 μgmL-1.This study has provided scientific baseline data on the therapeutic properties of P. dysenterica. KEYWORDS:Pulicaria dysenterica, essential oil,antimicrobial activity,citotoxicity

Beta-Caryophyllene, a Cannabinoid Receptor Type 2 Selective Agonist, in Emotional and Cognitive Disorders.

Mental disorders account for one of the most prevalent categories of the burden of disease worldwide, with depression expected to be the largest contributor by 2030, closely followed by anxiety. The COVID-19 pandemic possibly exacerbated these challenges, especially amongst adolescents, who experienced isolation, disrupted routines, and limited healthcare access. Notably, the pandemic has been associated with long-term neurological effects known as "long-COVID", characterized by both cognitive and psychopathological symptoms. In general, psychiatric disorders, including those related to long-COVID, are supposed to be due to widespread inflammation leading to neuroinflammation. Recently, the endocannabinoid system (ECS) emerged as a potential target for addressing depression and anxiety pathophysiology. Specifically, natural or synthetic cannabinoids, able to selectively interact with cannabinoid type-2 receptor (CB2R), recently revealed new therapeutic potential in neuropsychiatric disorders with limited or absent psychotropic activity. Among the most promising natural CB2R ligands, the bicyclic sesquiterpene β-caryophyllene (BCP) has emerged as an excellent anti-inflammatory and antioxidant therapeutic agent. This review underscores BCP's immunomodulatory and anti-inflammatory properties, highlighting its therapeutic potential for the management of depression and anxiety.

Association effect of the phytocannabinoid beta-caryophyllene and indomethacin carried in topical nanoemulgels: an evaluation by in vivo anti-inflammatory model

The sesquiterpene β-caryophyllene, classified as a phytocannabinoid compound, has been widely studied owing to its multi-target action. In addition, this compound has demonstrated application as a skin permeation promoter. In this context, this study aimed to evaluate the feasibility of associating β-caryophyllene and indomethacin in the oily core of hydrogel thickened nanoemulsions, as well as, to evaluate the in vivo anti-inflammatory effect of this association by croton oil ear edoema induced model. After topical application, the nanoemulgels resulted in increased edoema mass when compared to the substances in their free form. Overall, the results differed from expected, and the data found may be owing to the specificities of the in vivo model applied, as well as the tested ratio between β-caryophyllene and indomethacin (200:1). New perspectives arise from the data found regarding the evaluation of the association of terpenic compounds with indomethacin in nanoemulsified systems.

An Update on Microbial Biosynthesis of β-Caryophyllene, a Sesquiterpene with Multi-Pharmacological Properties

The sesquiterpene β-caryophyllene (BCP) is a major component of various plant essential oils, to which it confers a unique spicy aroma. It is mainly used as a fragrance additive in the food, cosmetic and perfume industries, with an annual consumption ranging between 100 and 1000 metric tons worldwide. Recently, BCP has attracted attention as a promising precursor for the production of high-density fuels and for its various biological activities and pharmacological effects. These include antioxidant, anti-inflammatory, anticancer, immune–modulatory, and many other activities. Due to its underlying mechanisms, β-caryophyllene interacts with various human receptors, including CB2 of the endocannabinoid system, which defines it as a phytocannabinoid with therapeutic potential for certain serious conditions. Due to β-caryophyllene’s high utility, various green and sustainable strategies for its production in microorganisms have been developed. This article provides an update on the state-of-the-art in this field to identify directions for further development to extend the compound’s potential.

Sesquiterpene-evoked phytochemical toxicity in PC12 neuronal cells reveals a variable degree of oxidative stress and alpha-tocopherol and glutathione-dependent protection

Phytochemicals are often promoted generally as antioxidants and demonstrate variable levels of reactive oxygen species (ROS) sequestration in vitro, which attributes to their neuroprotective bioactivity. Sesquiterpenes from cannabis and essential oils may demonstrate bifunctional properties towards cellular oxidative stress, possessing pro-oxidant activities by generating ROS or scavenging ROS directly. Sesquiterpenes can also oxidize forming sesquiterpene oxides, however the relative contribution they make to the bioactivity or cytotoxicity of complex botanical extracts more generally is unclear, while selected cannabis-prevalent terpenes such as β-caryophyllene may also activate cannabinoid receptors as part of their biological activity. In the present study, we investigated selected sesquiterpenes β-caryophyllene and humulene and their oxidized forms (β-caryophyllene oxide and zerumbone, respectively) against established antioxidants (ascorbic acid, α-tocopherol, and glutathione) and in the presence of cannabinoid receptor 1 and cannabinoid receptor 2 antagonists, to gain a better understanding of the molecular and cellular mechanisms of neuroprotection versus neurotoxicity in semi-differentiated rat neuronal phaeochromocytoma (PC12) cells. Our results demonstrate that the sesquiterpenes β-caryophyllene, humulene and zerumbone possess concentration-dependent neurotoxic effects in PC12 cells. Both β-caryophyllene- and humulene-evoked toxicity was unaffected by CB1 or CB2 receptor antagonism, demonstrating this occurred independently of cannabinoid receptors. Both glutathione and α-tocopherol were variably able to alleviate the concentration-dependent loss of PC12 cell viability from exposure to β-caryophyllene, humulene and zerumbone. During 4-hour exposure to sesquiterpenes only modest increases in ROS levels were noted in PC12 cells, with glutathione co-incubation significantly inhibiting intracellular ROS production. However, significant increases in ROS levels in PC12 cells were demonstrated during 24-hour incubation with either antioxidants or sesquiterpenes individually, and with additive toxicity exhibited in combination. Overall, the results highlight a concentration-dependent profile of sesquiterpene neurotoxicity independent of cannabinoid receptors and dissociated from the formation of reactive oxygen species as a marker or correlate to the loss of cell viability.

Chemical Composition and Antimicrobial Activity against the Listeria monocytogenes of Essential Oils from Seven Salvia Species.

In recent years, essential oils (EOs) have received interest due to their antibacterial properties. Accordingly, the present study aimed to investigate the effectiveness of the EOs obtained from seven species of Salvia on three strains of Listeria monocytogenes (two serotyped wild strains and one ATCC strain), a bacterium able to contaminate food products and cause foodborne disease in humans. The Salvia species analysed in the present study were cultivated at the Botanic Garden and Museum of the University of Pisa, and their air-dried aerial parts were subjected to hydrodistillation using a Clevenger apparatus. The obtained EOs were analysed via gas chromatography coupled with mass spectrometry for the evaluation of their chemical composition, and they were tested for their inhibitory and bactericidal activities by means of MIC and MBC. The tested Eos showed promising results, and the best outcomes were reached by S. chamaedryoides EO, showing an MIC of 1:256 and an MBC of 1:64. The predominant compounds of this EO were the sesquiterpenes caryophyllene oxide and β-caryophyllene, together with the monoterpenes bornyl acetate and borneol. These results suggest that these EOs may possibly be used in the food industry as preservatives of natural origins.

Pterodon emarginatus Seed Preparations: Antiradical Activity, Chemical Characterization, and In Silico ADMET Parameters of β-caryophyllene and Farnesol.

The study of medicinal plants and their active compounds is relevant to maintaining knowledge of traditional medicine and to the development of new drugs of natural origin with lower environmental impact. From the seeds of the Brazilian plant Pterodon emarginatus, six different preparations were obtained: essential oil (EO), ethanol extract (EthE) prepared using the traditional method, and four extracts using solvents at different polarities, such as n-hexane, chloroform, ethyl acetate, and methanol (HexE, ChlE, EtAE, and MetE). Chemical characterization was carried out with gas chromatography, allowing the identification of several terpenoids as characteristic components. The two sesquiterpenes β-caryophyllene and farnesol were identified in all preparations of Pterodon emarginatus, and their amounts were also evaluated. Furthermore, the total flavonoid and phenolic contents of the extracts were assessed. Successively, the antiradical activity with DPPH and ORAC assays and the influence on cell proliferation by the MTT test on the human colorectal adenocarcinoma (HT-29) cell line of the preparations and the two compounds were evaluated. Lastly, an in silico study of adsorption, distribution, metabolism, excretion, and toxicity (ADMET) showed that β-caryophyllene and farnesol could be suitable candidates for development as drugs. The set of data obtained highlights the potential medicinal use of Pterodon emarginatus seeds and supports further studies of both plant preparations and isolated compounds, β-caryophyllene and farnesol, for their potential use in disease with free radical involvement as age-related chronic disorders.

The chemical composition of the aerial parts’ essential oil of Nepeta apuleji Ucria (Lamiaceae) growing in Sicily (Italy)

The genus Nepeta L. (Lamiaceae) comprises about 300 species as annual or perennial herbs or small shrubs, spread in central and southern Europe, the Near East, central and southern Asia, and some areas of Africa. Several species have been used in the traditional medicine. In the present study, the chemical composition of the essential oils from aerial parts of two populations of Nepeta apuleji Ucria collected in Sicily, a rare species, growing also in South Spain and NW Africa, were analysed by GC-MS. No one has been previously worked and published on the essential oil of this species. Main constituents of the two oils of the two populations were the monoterpenes β-pinene (11.6–6.3%) and γ-terpinene (9.4–5.0%), and the sesquiterpenes β-caryophyllene (11.9–9.8%) and germacrene D (1.8–13.0%). The chemical profile of the two essential oils presented herein and they compared with previously investigated Nepeta taxa oils, reported in the article.

Metabolomic Approach Based on Analytical Techniques for the Detection of Secondary Metabolites from Humulus lupulus L. Dried Leaves.

Currently, the leaves of the hop plant (Humulus lupulus L.) are an unexploited and still little-investigated agricultural by-product. In our study, with the aim of exploring the metabolome of dried hop leaves (Chinook cultivar), a metabolomic approach was applied using multiple analytical tools such as SPME/GC-MS, GC-MS, PTR-ToF-MS, and NMR to identify the secondary metabolites. The obtained results showed the presence of a high number of components belonging to different chemical classes. In fact, thanks to the multi-methodological approach, volatile organic compounds (VOCs) with low molecular weight, terpenic compounds, fatty acids, sugars, amino acids, organic acids, and alcohols have been detected and identified. Among the revealed terpenes in the untreated matrix, the sesquiterpenes α-humulene, β-caryophyllene, and α-copaene were the most abundant. Among the saturated and unsaturated fatty acids, palmitic and linolenic acids, respectively, were those with the highest relative percentages. Particularly relevant was the sugar content, where sucrose was the main exponent while glutamate and asparagine were the principal detected amino acids. Conversely, alcohols and organic acids were the least abundant compound classes, and xanthohumol was also identified in the methanolic extract.

Anti-Coccal Activity and Composition of the Essential Oils and Methanolic Extracts Obtained from Brewing Quality Humulus lupulus L. Hop Pellets.

This study examined the chemical composition and anti-coccal properties of essential oils and methanolic extracts of six different Humulus lupulus L. varieties from Poland: Iunga, Marynka, Sybilla, Magnum, Tradition and Chinook. The activity of an α-acid-enriched fraction of methanolic extracts was also studied. The chemical composition of essential oils and extracts was determined by gas chromatography-mass spectrometry (GC/MS) and liquid chromatography-mass spectrometry (LC/MS) techniques. The compounds characteristic to H. lupulus extracts include xanthohumol, α-acids, β-acids, and prenylated flavonoids. Essential oil compositions showed a high prevalence of monoterpene hydrocarbon, myrcene and sesquiterpene hydrocarbons, α-humulene and β-caryophyllene. The antimicrobial activity was investigated against eight human cocci pathogenic strains: Staphylococcus aureus MRSA (ATCC 43300), S. aureus MRSA (29213), S. aureus MSSA (ATCC 29213), S. epidermidis (ATCC 12228), Enterococcus faecalis (ATCC 29212), E. faecalis VRE (ATCC 51299), E. faecium (ATCC 19434) and Micrococcus luteus (ATCC 10240). The lowest minimum inhibitory concentrations (MIC) were obtained for extracts and essential oils from Iunga hop samples. Extracts were significantly more active than essential oils. The most susceptible strain to both essential oils and extracts was M. luteus, whilst the least susceptible was E. faecium. The antimicrobial activity correlated with a high concentration of xanthohumol of active extracts rather than with the content of α-acids. Xanthohumol showed considerable activity against MRSA with an MIC value of 3.9 µg/mL. The activity of the α-acid-enriched fraction was mediocre compared to the results of all extracts.

Disease-modifying effects of cannabidiol, β-caryophyllene and their combination in Syn1-Cre/Scn1aWT/A1783V mice, a preclinical model of Dravet syndrome

Cannabidiol (CBD) has been recently approved as an antiseizure agent in Dravet Syndrome (DS), a pediatric epileptic encephalopathy, but CBD could also be active against associated comorbidities. Such associated comorbidities were also attenuated by the sesquiterpene β-caryophyllene (BCP). Here, we have compared the efficacy of both compounds and further initiated the analysis of a possible additive effect between both compounds in relation with these comorbidities using two experimental approaches. The first experiment was aimed at comparing the benefits of CBD and BCP, including their combination in conditional knock-in Scn1a-A1783V mice, an experimental model of DS, treated since the postnatal day 10th to 24th. As expected, DS mice showed impairment in limb clasping, delay in the appearance of hindlimb grasp reflex and additional behavioural disturbances (e.g., hyperactivity, cognitive deterioration, social interaction deficits). This behavioural impairment was associated with marked astroglial and microglial reactivities in the prefrontal cortex and the hippocampal dentate gyrus. BCP and CBD administered alone were both able to partially attenuate the behavioural disturbances and the glial reactivities, with apparently greater efficacy against glial reactivities obtained with BCP, whereas superior effects in a few specific parameters were obtained when both compounds were combined. In the second experiment, we investigated this additive effect in cultured BV2 cells treated with BCP and/or CBD and stimulated with LPS. As expected, addition of LPS induced a marked increase in several inflammation-related markers (e.g., TLR4, COX-2, iNOS, catalase, TNF-α, IL-1β), as well as elevated Iba-1 immunostaining. Treatment with BCP or CBD attenuated these elevations, but, again and in general, superior results were obtained when both cannabinoids were combined. In conclusion, our results support the interest to continue investigating the combination of BCP and CBD to improve the therapeutic management of DS in relation with their disease-modifying properties.

The hops (Humulus lupulus) genome contains a mid-sized terpene synthase family that shows wide functional and allelic diversity

BackgroundHops (Humulus lupulus L.) are a dioecious climbing perennial, with the dried mature “cones” (strobili) of the pistillate/female inflorescences being widely used as both a bittering agent and to enhance the flavour of beer. The glandular trichomes of the bract and bracteole flowering structures of the cones produce an abundance of secondary metabolites, such as terpenoids, bitter acids and prenylated phenolics depending on plant genetics, developmental stage and environment. More knowledge is required on the functional and allelic diversity of terpene synthase (TPS) genes responsible for the biosynthesis of volatile terpenes to assist in flavour-directed hop breeding.ResultsMajor volatile terpene compounds were identified using gas chromatography–mass spectrometry (GC–MS) in the ripe cones of twenty-one hop cultivars grown in New Zealand. All cultivars produced the monoterpene β-myrcene and the sesquiterpenes α-humulene and β-caryophyllene, but the quantities varied broadly. Other terpenes were found in large quantities in only a smaller subset of cultivars, e.g. β-farnesene (in seven cultivars) and α-pinene (in four). In four contrasting cultivars (Wakatu™, Wai-iti™, Nelson Sauvin™, and ‘Nugget’), terpene production during cone development was investigated in detail, with concentrations of some of the major terpenes increasing up to 1000-fold during development and reaching maximal levels from 50–60 days after flowering. Utilising the published H. lupulus genome, 87 putative full-length and partial terpene synthase genes were identified. Alleles corresponding to seven TPS genes were amplified from ripe cone cDNA from multiple cultivars and subsequently functionally characterised by transient expression in planta. Alleles of the previously characterised HlSTS1 produced humulene/caryophyllene as the major terpenes. HlRLS alleles produced (R)-(-)-linalool, whilst alleles of two sesquiterpene synthase genes, HlAFS1 and HlAFS2 produced α-farnesene. Alleles of HlMTS1, HlMTS2 and HlTPS1 were inactive in all the hop cultivars studied.ConclusionsAlleles of four TPS genes were identified and shown to produce key aroma volatiles in ripe hop cones. Multiple expressed but inactive TPS alleles were also identified, suggesting that extensive loss-of-function has occurred during domestication and breeding of hops. Our results can be used to develop hop cultivars with novel/improved terpene profiles using marker-assisted breeding strategies to select for, or against, specific TPS alleles.

Anti-inflammatory effects of α-humulene and β-caryophyllene on pterygium fibroblasts.

To investigate the anti-inflammatory effects of the sesquiterpenes α-humulene and β-caryophyllene on pterygium fibroblasts. Primary cultures of pterygium fibroblasts were established. Third passage pterygium fibroblasts were exposed to α-humulene and β-caryophyllene separately and together. The cell viability was assessed by 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide (MTT) assay at 12, 24, 48, and 72h after exposure. The levels of the inflammatory cytokines interleukin (IL)-1β, IL-6, IL-8, tumor necrosis factor (TNF)-α and IL-10 in the conditioned culture medium were assessed by enzyme-linked immunosorbent assay (ELISA) at 12, 24 and 48h after exposure. Data were statistically analyzed using Friedman repeated measures analysis of variances on ranks. The 25 µmol/L β-caryophyllene induced significant decrease in the IL-6 production by pterygium fibroblasts 48h after the exposure (P=0.041). The levels of IL-1β, IL-8, IL-10, and TNF-α were very low and had no statistically significant variations after exposure to α-humulene, β-caryophyllene, or both compounds together. The exposure to 25 µmol/L of β-caryophyllene significantly reduce the production of IL-6 by pterygium fibroblasts after 48h. This sesquiterpene may be a potential alternative adjuvant agent for the treatment of pterygium.

Unravelling the Chemotaxonomic Identity of "White" and "Black" Oregano (Origanum vulgare) in Northern Greece.

The two types of oregano used by the inhabitants of the villages of Μount Belles (GR1260001), the "white" oregano with white flowers and "black" oregano with purple flowers, were studied. The two oregano types were collected from five localities along an altitudinal gradient from 217 m up to 1299 m. "White" oregano, was found in the three lowland regions (up to 752 m) where the Pannonian-Balkanic turkey oak-sessile oak forest habitat (code 91M0) dominates. The "black" oregano was collected from the two higher altitudes, at 1177 m and 1299 m, where the Asperulo-Fagetum beech forest habitat (9130) occurs. Measurements of the density and size of peltate glandular hairs (sessile glands) on calyces, bracts, and leaves suggest that "white" oregano is distinguished by its conspicuous - apparently larger - glands. These differences were reflected in the total essential oil content, with the "white" oregano being much richer (up to 4.3 mL/100 g dry weight) than the "black" (up to 0.6%). Striking differences have also been found in the volatile fraction of their essential oil composition. The "white" oregano oils were characterized by the high content of carvacrol (up to 92.6% of identified peaks, by Headspace GC-MS). On the other hand, the two "black" oregano oils have a different aromatic profile, first reported from Greece, with main components including the sesquiterpenes β-caryophyllene, D-germacrene, δ-cadinene and β-bisabolene. The results so far indicate that "white" and "black" oregano, Origanum vulgare subsp. hirtum and subsp. vulgare respectively, can be clearly distinguished either by their morphological (glandular) differences or by chemical (essential oil) composition.

β-Caryophyllene Counteracts Chemoresistance Induced by Cigarette Smoke in Triple-Negative Breast Cancer MDA-MB-468 Cells.

Exposure to cigarette smoke (CS) has been associated with an increased risk of fatal breast cancers and recurrence, along with chemoresistance and chemotherapy impairment. This strengthens the interest in chemopreventive agents to be exploited both in healthy and oncological subjects to prevent or repair CS damage. In the present study, we evaluated the chemopreventive properties of the natural sesquiterpene β-caryophyllene towards the damage induced by cigarette smoke condensate (CSC) in triple negative breast cancer MDA-MB-468 cells. Particularly, we assessed the ability of the sesquiterpene to interfere with the mechanisms exploited by CSC to promote cell survival and chemoresistance, including genomic instability, cell cycle progress, autophagy/apoptosis, cell migration and related pathways. β-Caryophyllene was found to be able to increase the CSC-induced death of MDA-MB-468 cells, likely triggering oxidative stress, cell cycle arrest and apoptosis; moreover, it hindered cell recovery, autophagy activation and cell migration; at last, a marked inhibition of the signal transducer and activator of transcription 3 (STAT3) activation was highlighted: this could represent a key mechanism of the chemoprevention by β-caryophyllene. Although further studies are required to confirm the in vivo efficacy of β-caryophyllene, the present results suggest a novel strategy to reduce the harmful effect of smoke in cancer patients and to improve the survival expectations in breast cancer women.

Transcriptome sequencing and gas chromatography–mass spectrometry analyses provide insights into β-caryophyllene biosynthesis in Brassica campestris

Sesquiterpenes are important defensive secondary metabolites and aroma components. However, limited information is available on the mechanism of sesquiterpene formation and composition in the non-heading Chinese cabbage (NHCC) leaf. Therefore, headspace solid-phase microextraction/gas chromatography–mass spectrometry (HS-SPME/GC–MS) combined with transcriptome analysis was used to study the mechanism of volatile organic compound formation. A total of 26 volatile organic compounds were identified in two NHCC cultivars ‘SZQ’ and ‘XQC’ and their F1 hybrids. Among these, sesquiterpene β-caryophyllene was identified only in ‘XQC’ and F1. Five genes encoding caryophyllene synthase were identified. The candidate β-caryophyllene synthase genes BcTPSa11 and BcTPSa21 had high expression levels only in ‘XQC’ and F1. In addition, several transcription factors of MYB-related, MYB, bHLH, and AP2/ERF families were identified by co-expression, suggesting that they regulate β-caryophyllene biosynthesis. Our results provide a molecular basis for sesquiterpene biosynthesis as well as insights into the regulatory network of β-caryophyllene in NHCC.

Óleos essenciais das partes aéreas de quatro espécies of Protium (Burseraceae) – Uma contribuição para a flora aromática da Reserva Florestal Adolpho Ducke, Amazonas, Brasil

The Adolpho Ducke Forest Reserve is a fragment of the Amazon Rainforest that has the highest density of collections deposited in the INPA herbarium, and this characterized, vascular flora has been an important basis for chemical studies. This paper describes the chemical composition of the volatiles of aerial parts of the four species of Protium that occurr in the Ducke Reserve. The essential oils obtained by hydrodistillation were analyzed using GC-FID and GC-MS. P. altsonii showed high percentages of the monoterpenes α-pinene (22.05%) and limonene (17.76%) in the leaves, and linear long-chain fatty alcohols, such as n-tetradecanol (19.93%) and hexadecanol (32.56%), in the branches. The essential oil from leaves of P. laxiflorum provided sesquiterpenes α-copaene (18.98%), epi-α-cadinol (9.17%) and β-caryophyllene (9.04%) as the main compounds. In P. pallidum, the sesquiterpenes caryophyllene oxide (29.72%), α-cadinol (28.82%) and epi-α-cadinol (13.96%) were predominant in the leaves, and α-cadinol (25.50%), α-eudesmol (22.29%) and caryophyllene oxide (12.81%) predominated in the branches. β-Caryophyllene (30.59%) and caryophyllene oxide (20.63%) were the main compounds in the leaves of P. paniculatum var. riedelianum. The results presented herein contribute to the knowledge of the aromatic flora of the Ducke Reserve.

Engineering of tomato type VI glandular trichomes for trans-chrysanthemic acid biosynthesis, the acid moiety of natural pyrethrin insecticides

Glandular trichomes, known as metabolic cell factories, have been proposed as highly suitable for metabolically engineering the production of plant high-value specialized metabolites. Natural pyrethrins, found only in Dalmatian pyrethrum (Tanacetum cinerariifolium), are insecticides with low mammalian toxicity and short environmental persistence. Type I pyrethrins are esters of the monoterpenoid trans-chrysanthemic acid with one of the three rethrolone-type alcohols. To test if glandular trichomes can be made to synthesize trans-chrysanthemic acid, we reconstructed its biosynthetic pathway in tomato type VI glandular trichomes, which produce large amounts of terpenoids that share the precursor dimethylallyl diphosphate (DMAPP) with this acid. This was achieved by coexpressing the trans-chrysanthemic acid pathway related genes including TcCDS encoding chrysanthemyl diphosphate synthase and the fusion gene of TcADH2 encoding the alcohol dehydrogenase 2 linked with TcALDH1 encoding the aldehyde dehydrogenase 1 under the control of a newly identified type VI glandular trichome-specific metallocarboxypeptidase inhibitor promoter. Whole tomato leaves harboring type VI glandular trichomes expressing all three aformentioned genes had a concentration of total trans-chrysanthemic acid that was about 1.5-fold higher (by mole number) than the levels of β-phellandrene, the dominant monoterpene present in non-transgenic leaves, while the levels of β-phellandrene and the representative sesquiterpene β-caryophyllene in transgenic leaves were reduced by 96% and 81%, respectively. These results suggest that the tomato type VI glandular trichome is an alternative platform for the biosynthesis of trans-chrysanthemic acid by metabolic engineering.