Terpenoid Composition Research Articles

Intraspecific plant chemodiversity at the individual and plot levels influences flower visitor groups with consequences for germination success

Abstract Chemodiversity, the diversity of specialised (secondary) metabolites, plays a crucial role in mediating interactions between plants and animals, including insect herbivores and mutualists. Chemodiversity can be observed at both the individual and the population level. However, the impacts of chemodiversity at these two levels on interactions between plants and floral visitors, mainly pollinators and floral herbivores (florivores), are only poorly understood. This study aimed to investigate the effects of chemodiversity at both individual (chemotype) and plot level on pollinators and florivores, examining their mutual interactions. To investigate these questions, we used individuals of the perennial Tanacetum vulgare differing in their terpenoid composition, representing different chemotypes. We planted individuals of five distinct chemotypes in a common garden design with homogeneous (five plants of the same chemotype) and heterogeneous (five different chemotypes) plots and observed flower visits in dependence of individual chemotype and plot type. Seeds were collected from a subset of plants and germination rates determined. Our findings revealed that chemodiversity at the plot level significantly influenced pollinator visitation, with more visits on plants of heterogeneous plots. We also observed marginally more pollinators on one of the chemotypes grown in homogeneous plots. In contrast, chemotype but not plot type had a significant effect on florivore visits. Pollinator and florivore species richness did not vary with plot type. Furthermore, a negative correlation was observed between pollinator and florivore visits in 1 year. Germination rates were positively correlated with pollinator visits and affected by chemotype but not by florivore visits or plot type. Synthesis. Our study emphasises the significance of the spatial level at which plant chemistry is perceived by flower visitors, potentially influencing the germination success of plants. Exploring the ecology of these visitors and the varying selection pressures they exert on floral chemistry can help to elucidate the evolutionary processes that maintain chemodiversity in natural environments. Read the free Plain Language Summary for this article on the Journal blog.

Genome-wide investigation of WRKY gene family in Lavandula angustifolia and potential role of LaWRKY57 and LaWRKY75 in the regulation of terpenoid biosynthesis.

The WRKY transcription factors are integral to plant biology, serving essential functions in growth, development, stress responses, and the control of secondary metabolism. Through the use of bioinformatics techniques, this research has effectively characterized 207 members of the WRKY family (LaWRKY) present in the entire genome of Lavandula angustifolia. Phylogenetic analysis classified LaWRKYs into three distinct categories based on conserved domains. Collinearity analysis revealed tandem repeats, segmental duplications, and whole genome duplications in LaWRKYs, especially for segmental duplication playing a significant role in gene family expansion. LaWRKYs displayed distinct tissue-specific expression profiles across six different tissues of L. angustifolia. Particularly noteworthy were 12 genes exhibiting high expression in flower buds and calyx, the primary sites of volatile terpenoid production, indicating their potential role in terpenoid biosynthesis in L. angustifolia. RT-qPCR analysis revealed a notable increase in the expression levels of most examined LaWRKY genes in flower buds in response to both intense light and low-temperature conditions, whereas the majority of these genes in leaves were primarily induced by drought stress. However, all genes exhibited downregulation following GA treatment in both flower buds and leaves. Overexpression of LaWRKY57 (La13G01665) and LaWRKY75 (La16G00030) in tobacco led to a reduction in the density of glandular trichomes on leaf surfaces, resulting in changes to the volatile terpenoid composition in the leaves. Specifically, the content of Neophytadiene was significantly elevated compared to wild-type tobacco, while compounds such as eucalyptol, cis-3-Hexenyl iso-butyrate, and D-Limonene were produced, which were absent in the wild type. These findings provide a valuable reference for future investigations into the biological functions of the WRKY gene family in L. angustifolia.

The Study of the Biologically Active Effect of the Rubia Tinctorum L. Plant on Rats with Experimental Kidney Stone Disease and Issues of Introduction

Since ancient times, madder dye (Rubia tinctorum L.) has been used in Uzbekistan to help alleviate stone deposits in organs. In the experiment we conducted, we aimed to demonstrate that this plant can prevent the occurrence of kidney stone disease in rats using an induced model of the disease. The kidney stone disease model in rats was created by administering ethylene glycol and ammonium chloride to the animals over a period of 10 days. The substances contained in the madder dye plant mitigated the effects of the substances used to induce the disease. According to the study results, simultaneous oral administration of the madder dye extract prevented the development of kidney stone disease in rats. The extract of Rubia tinctorum L. was found to be highly effective, showing a significant nephroprotective effect due to its specific and rich composition of terpenes and terpenoids.

Transcriptome Analyses Reveal Differences in the Metabolic Pathways of the Essential Oil Principal Components of Different Cinnamomum Chemotypes

The genus Cinnamomum exhibits a rich variety of chemotypes and is an economically important essential oil (EO)-producing plant belonging to the family Lauraceae. Here, we aimed to explore the potential differences in the terpenoid (the principal components of EOs) biosynthesis pathways of different chemotypes at the molecular level in four Cinnamomum species—C. camphora var. linaloolifera, C. kanehirae, C. longipaniculatum, and C. micranthum. Gas chromatography–mass spectrometry (GC-MS) was employed to elucidate the discrepancies in the chemical profiles and compositions of leaf EO terpenoids among the four Cinnamomum species. The results revealed significant variations in leaf EO yields. The main constituents of the leaf EOs from C. camphora var. linaloolifera and C. kanehirae were the acyclic monoterpene linalool, and those of C. longipaniculatum and C. micranthum were the monoterpene eucalyptol and the sesquiterpene β-caryophyllene, respectively. Furthermore, a comparative transcriptome analysis of the leaves from the four Cinnamomum species revealed that differentially expressed genes (DEGs) were significantly enriched in terpene-related entries. Specifically, 42 and 24 DEGs were significantly enriched to the mevalonate (MVA)/2-methylerythritol 4-phosphate (MEP) pathways and terpene synthase (TPS) activity, respectively. Most genes encoding proteins involved in the terpenoid precursor MVA and MEP pathways exhibited differential expression across the four species, which correlated with the distinct terpenoid profiles observed in their leaf EOs. Four acyclic monoterpene linalool synthase genes—Maker00024100, Maker00014813, Maker00014818, and Maker00018424—were highly expressed in C. camphora var. linaloolifera and C. kanehirae. A monoterpene eucalyptol synthesis gene, Maker00001509, was highly expressed in C. longipaniculatum, and a sesquiterpene β-stigmasterol synthesis gene, Maker00005791, was highly expressed in C. micranthum. These expression levels were subsequently validated through quantitative real-time polymerase chain reaction (qRT-PCR). In conclusion, the combined results of the GC-MS and transcriptome analyses revealed a strong correlation between the metabolite content of the EOs and gene expression. This research contributes to a better understanding of the differences in terpene accumulation in various chemotypes of Cinnamomum at the molecular and mechanistic levels, laying a solid foundation for the cultivation of an ideal Cinnamomum variety.

Exogenous stimulation of Tanacetum vulgare roots with pipecolic acid leads to tissue-specific responses in terpenoid composition.

Tanacetum vulgare L., tansy, is a perennial plant with highly variable terpenoid composition, with mono- and sesquiterpenoids being the most abundant. The high diversity of terpenoids plays an important role in mediating ecological interactions. However, the distribution of terpenoids in different tissues and inducibility of terpenoids in these tissues via biotic stress are poorly understood. We investigated changes in terpenoid profiles and concentrations in different organs following treatment of roots with pipecolic acid (Pip), a non-proteinogenic amino acid that triggers defence responses leading to induce systemic resistance (SAR) in plants. Tansy leaves and midribs contained mainly monoterpenoids, while coarse and fine roots contained mainly sesquiterpenoids. Rhizomes contained terpenoid profiles of both midribs and roots but also unique compounds. Treatment with Pip led to an increase in concentrations of mono- and sesquiterpenoids in all tissues except rhizomes. However, significantly more sesquiterpenoids was formed in root tissues in response to Pip treatment, compared to shoots. The metabolic atlas for terpenoids presented here shows that there is exceptionally strong differentiation of terpenoid patterns and terpenoid content in different tissues of tansy. This, together with differential inducibility by Pip, suggests that the chemical diversity of terpenoids may play an important role in tansy ecological interactions and defence against biotic stressors that feed on below- and aboveground organs.

Lavandula angustifolia Herb from Ukraine: Comparative Chemical Profile and in vitro Antioxidant Activity.

Lavandula L. genus plants have always been relevant as medicines for various purposes in food, medicine, pharmaceuticals, cosmetology and aromology. Ukraine is a new territory in the mass plant cultivation and lavender essential oil production. Therefore, the issue of integrated use of herbal raw materials and their intended use is still relevant. For the first time, ten samples of Lavendula angustifolia herb from 5 growing regions of Ukraine were studied for the composition and content of polyphenols and terpenoids using HPLC and HPTLC methods, respectively, to assess the prospects and quality of herbal raw materials. The results obtained showed that L. angustifolia herb has pronounced antioxidant activity due to the high content of phenolic compounds, namely hyperoside (5.665-11.629 mg/g), vanillic acid (5.986-11.196 mg/g), rosmarinic acid (0.211 to 1.488 mg/g), caffeic acid (0.369-3.835 mg/g), chlorogenic acid (0.239-4.619 mg/g), genistein-7-O-glucoside, as well as due to the presence of linalool and linalyl acetate, which was confirmed by qualitative analysis. The total antioxidant activity was the highest in samples from Lviv Botanical Garden (0.293 Trolox mg/mL), Kyiv OLawander (0.288 Trolox mg/mL), Kharkiv Bohodukhiv (0.270 Trolox mg/mL) which is due to the qualitative composition of phenolic compounds. At the same time, the most intense zones of terpenoids in lavender herb were noted for images from Kharkiv region Lebiazhe and Kitchenkivka villiges. Cluster analysis showed priority in the selection of marker compounds (vanillic acid, hyperoside, chlorogenic acid, rosmarinic acid) for lavender herb based on their quantitative content in the samples. In the future, lavender herb from Ukraine can be considered as a promising raw material with neuroprotective properties as part of its complex use, as research continues.

Effect of Hemp Extraction Procedures on Cannabinoid and Terpenoid Composition.

A variety of techniques have been developed to extract hemp phytochemicals for research and consumption. Some of the most common processes in the industry include supercritical CO2 extraction, hydrodistillation, and solvent-based (ethanol) extractions. Each of these processes has the potential to differentially extract various phytochemicals, which would impact their efficacy, tolerability, and safety. However, despite these differences, there has been no direct comparison of the methods and the resulting phytochemical composition. This work aimed to compare cannabinoid and terpene profiles using the three primary commercial procedures, using hemp inflorescence from a CBD/CBG dominant Cannabis sativa L. cultivar. Extracts were then evaluated for their terpene and cannabinoid content using GC-MS and LC-MS/MS, respectively. Hydrodistilled extracts contained the most variety and abundance of terpenes with β-caryophyllene to be the most concentrated terpene (25-42 mg/g). Supercritical CO2 extracts displayed a minimal variety of terpenes, but the most variety and abundance of cannabinoids with CBD ranging from 12.8-20.6 mg/g. Ethanol extracts contained the most acidic cannabinoids with 3.2-4.1 mg/g of CBDA along with minor terpene levels. The resulting extracts demonstrated substantially different chemical profiles and highlight how the process used to extract hemp can play a large role in product composition and potential biological effects.

Citrus limon var. pompia Camarda var. nova: A Comprehensive Review of Its Botanical Characteristics, Traditional Uses, Phytochemical Profile, and Potential Health Benefits.

Citrus limon var. pompia Camarda var. nova, commonly known as pompia, is a distinctive citrus ecotype native to Sardinia, notable for its unique botanical, phytochemical, and potential health benefits. It holds cultural significance as a traditional food product of Sardinia, recognized by the Italian Ministry of Agricultural Food and Forestry Policies. This comprehensive review examines pompia's traditional uses, taxonomic classification, pomological characteristics, phytochemical profile, and potential health benefits. Pompia phytochemical analyses reveal a rich composition of flavonoids and terpenoids, with notable concentrations of limonene, myrcene, and various oxygenated monoterpenes. Pompia essential oils are primarily extracted from its peel and leaves. Peel essential oils exhibit a high concentration of the monoterpene limonene (82%) and significantly lower quantities of myrcene (1.8%), geranial (1.7%), geraniol (1.5%), and neral (1.4%). In its rind extract, flavanones such as naringin (23.77 µg/mg), neoeriocitrin (46.53 µg/mg), and neohesperidin (44.57 µg/mg) have been found, along with gallic acid (128.3 µg/mg) and quinic acid (219.67 µg/mg). The main compounds detected in the essential oils from pompia leaves are oxygenated monoterpenes (53.5%), with limonene (28.64%), α-terpineol (41.18%), geranial (24.44%), (E)-β-ocimene (10.5%), linalool (0.56%), and neryl acetate (13.56%) being particularly prominent. In pompia juice, the presence of phenolic compounds has been discovered, with a composition more similar to lemon juice than orange juice. The primary flavonoid identified in pompia juice is chrysoeriol-6,8-di-C-glucoside (stellarin-2) (109.2 mg/L), which has not been found in other citrus juices. The compound rhoifolin-4-glucoside (17.5 mg/L) is unique to pompia juice, whereas its aglycone, rhoifolin, is found in lemon juice. Other flavonoids identified in pompia juice include diosmetin 6,8-C-diglucoside (54.5 mg/L) and isorhamnetin 3-O-rutinoside (79.4 mg/L). These findings support the potential of pompia in developing nutraceuticals and natural health products, further confirmed by its compounds' antioxidant, anti-inflammatory and antibacterial properties. Future research should focus on optimizing extraction methods, conducting clinical trials to evaluate efficacy and safety, and exploring sustainable cultivation practices. The potential applications of pompia extracts in food preservation, functional foods, and cosmetic formulations also warrant further investigation. Addressing these areas could significantly enhance pompia's contribution to natural medicine, food science, and biotechnology.

FhMYB108 Regulates the Expression of Linalool Synthase Gene in Freesia hybrida and Arabidopsis.

Acting as the most abundant and widely distributed volatile secondary metabolites in plants, terpenoids play crucial roles in diverse physiological regulations and metabolic processes. Terpene synthases play a decisive role in determining the composition and diversity of terpenoids. Though the regulation of terpene synthases has been extensively investigated across various plant species, limited studies have focused on the upstream transcriptional regulation of terpene synthases. In this study, we have identified linalool as the predominant volatile compound that is released gradually from Freesia hybrida flowers throughout flower blooming. In the context of the transcriptome, a typical MYB transcription factor, FhMYB108, was screened based on homologous gene comparison. FhMYB108 is capable of regulating the expression of FhTPS1, and both their expression levels showed gradual increase during flower opening. Moreover, FhMYB108 exerts a stimulatory effect on the transcription of Arabidopsis thaliana AtTPS14, while no significant increase in AtTPS14 expression is observed upon the stabilization of FhMYB108 in A. thaliana. The highly expressed AtMYC2 in A. thaliana could interact with FhMYB108 to suppress the activation of AtTPS14 by FhMYB108. The present study not only elucidates the regulatory mechanism underlying linalool synthesis but also discovers the synergistic effect of MYB and bHLH transcription factors in governing the biosynthesis of volatile terpenoids.

Whole-genome resequencing identifies exonic single-nucleotide variations in terpenoid biosynthesis genes of the medicinal and aromatic plant common sage (Salvia officinalis L.)

Common sage (Salvia officinalis L.), the type species of the genus Salvia, is a historically acknowledged medicinal and aromatic plant that is utilized in several different industries for manufacturing diverse end products, including food, pharmaceuticals, cosmetics, personal hygiene products and insect repellants. The medical uses of sage essential oil terpenoids have made these secondary metabolites a focus of medical/pharmaceutical chemistry research. In the present work, the common sage genome was resequenced and assembled, and the protein-encoding gene content was annotated. The terpenoid biosynthesis gene repertoire, which includes 75 terpene synthase and 67 terpenoid backbone biosynthesis pathway genes, was predicted and located on assembly scaffolds, revealing tandem duplication blocks on the chromosomes. Variant analysis identified 188 variable single-nucleotide loci in the coding sequences of sage terpenoid biosynthesis genes. A total of 24,570 single-nucleotide polymorphisms were identified in the common sage total exome, representing a database of potential variable loci for targeted genotyping research. Given that terpene synthase activity is highly prone to modulation by point mutations and that the genotype plays an important role in the complex traits of terpenoid composition, single-nucleotide polymorphisms located in coding sequences constitute candidate functional markers that can be associated with terpenoid compositional traits in future research.

Chemodiversity affects preference for Tanacetum vulgare chemotypes in two aphid species

Plants of the same species can strongly differ in their specialized metabolite profiles, which can affect insect presence and abundance in the field. However, how specialized chemistry shapes plant attractiveness to herbivorous insects is not fully understood. Here, we used common tansy Tanacetum vulgare, Asteraceae) – a perennial plant that is highly diverse in terpenoid composition and is known to have variable chemotypes – to test whether 1) plants with different chemotype profiles differ in attractiveness to two specialist aphid species, Macrosiphoniella tanacetaria and Uroleucon tanaceti, in pairwise choice assays; 2) the diversity of the terpenoid blend affects plant attractiveness to aphids; 3) how plant chemical traits relate to plant morphological traits and which traits best explain aphid preference. We found that M. tanacetaria preferred two out of five chemotypes, dominated by α‐thujone/β‐thujone and β‐trans‐chrysanthenyl acetate, while avoiding a chemotype dominated by α‐pinene/sabinene. Uroleucon tanaceti showed no clear preference towards chemotypes, but when given a choice between chemotypes dominated by α‐thujone/β‐thujone and by α‐pinene/sabinene, they preferred the former. Importantly, plant attractiveness to aphids was marginally negatively correlated with chemodiversity, i.e. the number of terpenoid compounds, in M. tanacetaria, but not in U. tanaceti. Interestingly, the relative concentration and number of terpenoids were generally higher in larger and bushier plants. Hence, we did not observe a tradeoff between plant growth and defence. We conclude that plant chemical composition affects plant attractiveness to aphids and hence may contribute to variation in natural aphid colonization patterns on plants of the same species.

Solvent effects on terpenoid compositions and antioxidant activities of Cinnamomum camphora (L.) J. Presl extracts and the main antioxidant agent evaluation through in vitro and in vivo assay

Plant secondary metabolites can protect organisms against oxidative stress caused by adverse environmental conditions. Cinnamomum camphora (L.) J. Presl contains plentiful terpenoids and is subdivided into 5 chemotypes. To develop natural antioxidants using the plant terpenoids, the terpenoid composition and antioxidant abilities of methanol, ethyl acetate, n-hexane and petroleum ether extracts from linalool and eucalyptol chemotypes were investigated, and the solvent effects on in vitro antioxidant activity of 8 main terpenoids were analyzed. Meanwhile, the in vivo effects of two strong antioxidant terpenoids were evaluated. For the two chemotypes, the 4 solvents exhibited the same extracting effects on the terpenoid types, but methanol extracts contained the highest content of terpenoids, which should contribute to their strongest scavenging activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) free radicals. In linalool and eucalyptol chemotype extracts, linalool, eucalyptol, ocimene, α-pinene, D-limonene, terpinene, β-pinene and longifolene were the 8 main terpenoids. Among the 4 solvents, the 8 terpenoids showed the strongest free radical-scavenging activity with methanol as the reaction medium, which might result from strong-polarity methanol easily activating C = C unsaturated bonds in these compounds. This might also contribute to the strongest scavenging activity of methanol extracts against free radicals. Among these main components, ocimene and longifolene separately showed the strongest activity in scavenging DPPH and ABTS free radical. In in vivo assay, the two compounds significantly lowered the reactive oxygen species (ROS) levels in Chlamydomonas reinhardtii, a single-celled model organism, under H2O2 stress, and the lowering effects gradually enhanced with increasing the compound concentration, resulting in the corresponding promoting effect on the algal growth. At the same concentration, longifolene showed the strongest effect on protecting the algal cells against oxidative stress. Therefore, methanol was suitable for extracting terpenoids in natural antioxidant development, and ocimene and longifolene were two strong antioxidant terpenoids without cell toxicity, with the latter having stronger in vivo antioxidant activity.Graphical

Optical discrimination of terpenes in citrus peels with a host:guest sensing array.

A simple aqueous host:guest sensing array can selectively discriminate between different types of citrus varietal from peel extract samples. It can also distinguish between identical citrus samples at varying stages of ripening. The discrimination effects stem from detection of changes in the terpenoid composition of the peel extracts by the host:guest array, despite the overwhelming excess of a single component, limonene, in each sample. The hosts are insensitive to limonene but bind other monoterpenes strongly, even though they are similar in structure to the major limonene component. This work demonstrates the capability of host:guest arrays in sensing target molecules in environments with the competing agents present at high abundances in the sample matrix.

Characterization and In Vitro Antioxidant and Anti-Inflammatory Activities of Ginsenosides Extracted from Forest-Grown Wild Panax quinquefolius L.

American ginseng (Panax quinquefolius L.) is known for its health benefits, which are attributed to various terpenoids. However, the specific composition and activities of these terpenoids in forest-grown wild American ginseng remain understudied. This study aimed to characterize the terpenoid composition, particularly triterpene saponins, in forest-grown wild American ginseng. The analysis revealed that triterpene saponins, notably American ginseng ginsenosides (AGGs), are the predominant active components, as identified through LC-MS/MS and HPLC. A subsequent in vitro evaluation of AGGs showcased their potent antioxidant capabilities, displaying the dose-dependent scavenging of free radicals and reducing agents. Moreover, AGGs demonstrated efficacy in reducing oxidative injury and intracellular ROS levels in RAW 264.7 macrophages treated with H2O2. In addition to their antioxidant properties, AGGs exhibited anti-inflammatory effects, significantly inhibiting NO and inflammatory substance production in lipopolysaccharide-treated RAW 264.7 macrophages. These findings highlight the potential of AGG-rich forest-grown wild American ginseng as a functional food with promising implications for improving human health.

Identification of algicidal monoterpenoids from four chemotypes of Cinnamomum camphora and their algicidal mechanisms on Microcystis aeruginosa

Cyanobacterial blooms cause serious environmental issues, and plant secondary metabolites are considered as new algaecide for controlling them. Cinnamomum camphora produces a wide spectrum of terpenoids and has 4 main chemotypes, including linalool, camphor, eucalyptol and borneol chemotype. To develop the new cyanobacterial algaecide by using suitable chemotype of Cinnamomum camphora and the main terpenoids, we analyzed the terpenoid composition in the 4 chemotype extracts, evaluated the algicidal effects of the extracts and their typical monoterpenoids on Microcystis aeruginosa, and investigated the algicidal mechanism of the stronger algicidal agents. Among the 4 chemotypes, eucalyptol and borneol chemotype extracts exhibited stronger algicidal effects. In the 4 chemotype extracts, monoterpenoids were the main compounds, of which linalool, camphor, eucalyptol and borneol were the typical components. Among the 4 typical monoterpenoids, eucalyptol and borneol showed stronger algicidal effects, which killed 78.8% and 100% M. aeruginosa cells, respectively, at 1.2 mM after 48 h. In 1.2 mM eucalyptol and borneol treatments, the reactive oxygen species levels markedly increased, and the caspase-3-like activity also raised. With prolonging the treatment time, M. aeruginosa cells gradually shrank and wrinkled, and the cell TUNEL fluorescence intensity and DNA degradation gradually enhanced, indicating that the lethal mechanism is causing apoptosis-like programmed cell death (PCD). Therefore, eucalyptol and borneol chemotype extracts and their typical monoterpenoids have the potential for developing as algaecides to control cyanobacteria through triggering apoptosis-like PCD.

The Capsicum terpenoid biosynthetic module is affected by spider-mite herbivory

In response to herbivory, Capsicum annuum leaves adapt their specialized metabolome that may protect the plant against herbivore feeding either directly or indirectly through volatile metabolites acting as cues for natural enemies of the herbivore. The volatile blend of spider-mite infested leaves differs from non-challenged leaves predominantly by a higher contribution of mono- and sesquiterpenes. In addition to these terpenoids released into the headspace, the terpenoid composition of the leaves alters upon herbivory. All this suggests an important role for terpenoids and their biosynthetic machinery in the defence against herbivory. Here, we show that the C. annuum genome contains a terpene synthase (TPS) gene family of 103 putative members of which structural analysis revealed that 27 encode functional enzymes. Transcriptome analysis showed that several TPS loci were differentially expressed upon herbivory in leaves of two C. annuum genotypes, that differ in susceptibility towards spider mites. The relative expression of upstream biosynthetic genes from the mevalonate and the methylerythritol phosphate pathway also altered upon herbivory, revealing a shift in the metabolic flux through the terpene biosynthetic module. The expression of multiple genes potentially acting downstream of the TPSs, including cytochrome P450 monooxygenases, UDP-glucosyl transferases, and transcription factors strongly correlated with the herbivory-induced TPS genes. A selection of herbivory-induced TPS genes was functionally characterized through heterologous expression and the products that these enzymes catalysed matched with the volatile and non-volatile terpenoids induced in response to herbivory.

Chemodiversity in flowers of Tanacetum vulgare has consequences on a florivorous beetle.

The chemical composition of plant individuals can vary, leading to high intraspecific chemodiversity. Diversity of floral chemistry may impact the responses of flower-feeding insects. Tanacetum vulgare plants vary significantly in their leaf terpenoid composition, forming distinct chemotypes. We investigated the composition of terpenoids and nutrients of flower heads and pollen in plants belonging to three chemotypes - dominated either by β-thujone (BThu), artemisia ketone (Keto) or a mixture of (Z)-myroxide, santolina triene, and artemisyl acetate (Myrox) - using different analytical platforms. We tested the effects of these differences on preferences, weight gain and performance of adults of the shining flower beetle, Olibrus aeneus. The terpenoid composition and diversity of flower heads and pollen significantly differed among individuals belonging to the above chemotypes, while total concentrations of pollen terpenoids, sugars, amino acids, and lipids did not differ. Beetles preferred BThu over the Myrox chemotype in both olfactory and contact choice assays, while the Keto chemotype was marginally repellent according to olfactory assays. The beetles gained the least weight within 48 h and their initial mortality was highest when feeding exclusively on floral tissues of the Myrox chemotype. Short-term weight gain and long-term performance were highest when feeding on the BThu chemotype. In conclusion, the beetles showed chemotype-specific responses towards different T.vulgare chemotypes, which may be attributed to the terpenoid composition in flower heads and pollen rather than to differences in nutrient profiles. Both richness and overall diversity are important factors when determining chemodiversity of individual plants and their consequences on interacting insects.

Terpenoid diversity and antimicrobial activity of five Himalayan Senecio species

The terpenoid composition of essential oils from the leaves of five Senecio species, viz., S. chrysanthemoides DC., S. rufinervis DC., S. graciliflorus DC., S. kunthianus and S. alatus Wall.ex DC., collected from the Indian Himalayan Region, was examined by GC, GC/MS, and NMR analysis. Comparison of the results with previous reports revealed new chemotype of S. chrysanthemoides and S. graciliflorus, whereas, S. kunthianus have been explored first time for their terpenoid composition. The analysis was carried out in order to discern the similarities and differences within the essential oil composition at their subspecies/chemotype level. Based on the major constituents of the essential oils, seven chemical groups were obtained. The antibacterial activity tests were also performed against five pathogenic bacteria and two fungi.

Transcriptional regulation modulates terpenoid biosynthesis of Pinus elliottii under drought stress

Global climate change has increased the frequency and severity of droughts, which may affect the biosynthesis of coniferous terpenes, but the regulatory mechanism is still unclear. We explored the mechanisms of terpenoid regulation in response to drought stress by resolving changes in terpenoid composition and gene expression under drought stress to better understand the expression profile of terpenoid synthesis in slash pine. We obtained three main results: (1) A total of 1393 differentially expressed genes (DEGs) were identified, mainly including MYB, AP2/ERF, WRKY and other transcription factors, which were reported to be associated with plant resistance. Real-time quantitative PCR (RT-qPCR) verified the reliability of transcriptomic data, and the analysis of its results shows a close correlation with the data obtained by RNA-seq. (2) A total of 39 DEGs encoding 7 types of the proteins that were identified in the terpene synthesis pathway; what’s more, TPS (e.g., PITA_24906, PITA_00655, PITA_09277) and CYP720B11 (PITA_22711) showed high expressions in diterpene synthesis. (3) A weighted coexpression network analysis (WGCNA) showed high correlations between levopimaric acid content and module genes expression. Network visualization of the 70 hub genes revealed this high degree of connectivity between PITA_24906 and other genes, suggesting that PITA_24906 might play a regulatory role in levopimaric acid under drought stress. Thus, the results of this study will lead to a better understanding of the defense mechanisms of slash pine and provide a basic reference for the management and genetic improvement of slash pine stands.

Geographical Classification of Saffron (Crocus Sativus L.) Using Total and Synchronous Fluorescence Combined with Chemometric Approaches.

There is an increasing interest in food science for high-quality natural products with a distinct geographical origin, such as saffron. In this work, the excitation-emission matrix (EEM) and synchronous fluorescence were used for the first time to geographically discriminate between Moroccan saffron from Taroudant, Ouarzazate, and Azilal. Moreover, to differentiate between Afghan, Iranian, and Moroccan saffron, a unique fingerprint was assigned to each sample by visualizing the EEM physiognomy. Moreover, principal component analysis (LDA) and linear discriminant analysis (LDA) were successfully applied to classify the synchronous spectra of samples. High fluorescence intensities were registered for Ouarzazate and Taroudant saffron. Yet, the Azilal saffron was distinguished by its low intensities. Furthermore, Moroccan, Afghan, and Iranian saffron were correctly assigned to their origins using PCA and LDA for different offsets (Δλ) (20-250 nm) such that the difference in the fluorescence composition of the three countries' saffron was registered in the following excitation/emission ranges: 250-325 nm/300-480 nm and 360-425 nm/500-550 nm. These regions are characterized by the high polyphenolic content of Moroccan saffron and the important composition of Afghan saffron, including vitamins and terpenoids. However, weak intensities of these compounds were found in Iranian saffron. Furthermore, a substantial explained variance (97-100% for PC1 and PC2) and an important classification rate (70-90%) were achieved. Thus, the non-destructive applied methodology of discrimination was rapid, straightforward, reliable, and accurate.