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Lettuce is the most highly consumed raw leafy vegetable crop eaten worldwide, making it nutritionally important in spite of its comparatively low nutrient density in relation to other vegetables. However, the perception of bitterness caused by high levels of sesquiterpenoid lactones and comparatively low levels of sweet tasting sugars limits palatability. To assess variation in nutritional and taste-related metabolites we assessed 104 members of a Lactuca sativa cv. Salinas x L. serriola (accession UC96US23) mapping population. Plants were grown in three distinct environments, and untargeted NMR and HPLC were used as a rapid chemotyping method, from which 63 unique Quantitative Trait Loci (QTL) were identified. We were able to identify putative regulatory candidate genes underlying the QTL for fructose on linkage group 9, which accounted for up to 36 % of our population variation, and which was stable across all three growing environments; and for 15-p-hydroxyyphenylacetyllactucin-8-sulfate on linkage group 5 which has previously been identified for its low bitterness, while retaining anti-herbivory field effects. We also identified a candidate gene for flavonoid 3,5- hydroxylase underlying a polyphenol QTL on linkage group 5, and two further candidate genes in sugar biosynthesis on linkage groups 2 and 5. Collectively these candidate genes and their associated markers can inform a route for plant breeders to improve the palatability and nutritional value of lettuce in their breeding programmes.

Sesquiterpene lactones (STLs) are a prominent group of plant secondary metabolites predominantly found in the Asteraceae family and have multiple ecological roles and medicinal applications. This review describes the evolutionary and ecological significance of STLs, highlighting their roles in plant defence mechanisms against herbivory and as phytotoxins, alongside their function as environmental signalling molecules. We also cover the substantial role of STLs in medicine and their mode of action in health and disease. We discuss the biosynthetic pathways and the various modifications that make STLs one of the most diverse groups of metabolites. Finally, we discuss methods for identifying and predicting STL biosynthesis pathways. This article is part of the theme issue 'The evolution of plant metabolism'. [ABSTRACT FROM AUTHOR]

Arctic ecosystems have long been thought to be minimal sources of volatile organic compounds (VOCs) to the atmosphere because of their low plant biomass and cold temperatures. However, these ecosystems experience rapid climatic warming that alters vegetation composition. Tundra vegetation VOC emissions have stronger temperature dependency than current emission models estimate. Thus, warming, both directly and indirectly (via vegetation changes) likely increases the release and alters the blend of emitted plant volatiles, such as isoprene, monoterpenes, and sesquiterpenes, from Arctic ecosystems. Climate change also increases the pressure of both background herbivory and insect outbreaks. The resulting leaf damage induces the production of volatile defense compounds, and warming amplifies this response. Soils function as both sources and sinks of VOCs, and thawing permafrost is a hotspot for soil VOC emissions, contributing to ecosystem emissions if the VOCs bypass microbial uptake. Overall, Arctic VOC emissions are likely to increase in the future, with implications for ecological interactions and atmospheric composition. [ABSTRACT FROM AUTHOR]

The root of Paeonia lactiflora pall. is a significant component of traditional Chinese medicine, with terpenoids and their glycosides, such as paeoniflorins, serving as key active ingredients known for their anti-inflammatory, hepatoprotective, and analgesic properties. By generating a transcriptome and functionally characterizing 32 terpene synthases (TPSs) from P. lactiflora, we successfully constructed 24 pESC-Trp-PlTPS expression vectors. Through expression in Saccharomyces cerevisiae engineered strains, we identified four mono-TPSs and five sesqui-TPSs that produce 18 compounds, including eight monoterpenes and ten sesquiterpenes in vitro. This includes a bifunctional enzyme (PlTPS22). Additionally, PlTPS21 was characterized as a pinene synthase with α-pinene as its main product. The expression pattern of PlTPS21 aligns closely with the accumulation patterns of paeoniflorins and α-pinene in the plant, suggesting that PlTPS21 is a key enzyme in the biosynthesis of paeoniflorin. [ABSTRACT FROM AUTHOR]

Abscisic acid (ABA) is an important phytohormone with diverse applications. It currently relies on the fermentation of Botrytis cinerea, which suffers from limited availability of genetic engineering tools. Here, Yarrowia lipolytica was engineered to enable de novo biosynthesis of ABA. To overcome the rate-limiting P450 enzymes, systematic engineering strategies were implemented. Firstly, the dissolved oxygen was increased to boost the activity of P450 enzymes. Secondly, the expansion of endoplasmic reticulum was implemented to improve the functional expression of P450 enzymes. Lastly, rate-limiting enzymes were assembled to facilitate substrate trafficking. Moreover, ABA production was further improved by strengthening the mevalonate pathway. Finally, the engineered strain produced 1221.45 mg/L of ABA in a 5-L bioreactor. The study provides effective approaches for alleviating rate-limiting P450 enzymes to enhance ABA production and achieve competitive industrial-level ABA production in Y. lipolytica.

Owing to the challenges of antimicrobial resistance, investigations of new antibiotics from medicinal plants are continuously being conducted. Peperomia pellucida is a pantropical plant used in traditional medicine for the treatment of various disorders. From the ethanol extract of a whole P. pellucida plant, one previously undescribed carotane sesquiterpene (pellucarotine), one known carotane sesquiterpene (daucol), and one phenylpropanoid (dillapiol) were isolated and structurally elucidated. Their structures were determined based on 1D and 2D NMR, HR-ESI-Mass, experimental, and computational electronic circular dichroism spectroscopic data and compared with those reported in the literature. Antimicrobial assay results showed that pellucarotine had an anti-infective effect on Candida albicans with an MIC of 512 µg/mL. [ABSTRACT FROM AUTHOR]

Agrobacterium tumefaciens can harm various fruit trees, leading to significant economic losses in agricultural production. It is urgent to develop new pesticides to effectively treat this bacterial disease. In this study, four new sesquiterpene derivatives, trichoderenes A-D (1-4), along with six known compounds (5-10), were obtained from the marine-derived fungus Trichoderma effusum. The structures of 1-4 were elucidated by extensive spectroscopic analyses, and the calculated ECD, ORD, and NMR methods. Structurally, the hydrogen bond formed between the 1-OH group and the methoxy group enabled 1 to adopt a structure resembling that of resorcylic acid lactones, thereby producing the ECD cotton effect. Compound 3 represents the first example of C12 norsesquiterpene skeleton. Compounds 1-10 were tested for their antimicrobial activity against A. tumefactions. Among them, compounds 1-3 and 8-10 exhibited inhibitory activity against A. tumefactions with MIC values of 3.1, 12.5, 12.5, 6.2, 25.0, and 12.5 µg/mL, respectively. [ABSTRACT FROM AUTHOR]

Atractylodes lancea rhizomes (ARs) are rich in essential oil, which contains a high amount of volatile organic compounds (VOCs), especially sesquiterpenes. The essential oil of A. lancea has high medicinal and economic value. In this study, we investigated the impact of alteration in light quality on the production and composition of VOCs in A. lancea. We applied red light, blue light, and mixed red and blue light of different ratios (red : blue = 3:1, 6:1, and 9:1) treatment on A. lancea plantlets and analyzed their VOCs by gas chromatography-mass spectrometry (GC-MS). Our results showed that light quality mainly affected the production rather than the composition of VOCs in A. lancea. We identified a total of 27 VOCs in the rhizome, 13 of them were sesquiterpenes. The concentration of sesquiterpenes increased as the proportion of red light increased. We performed transcriptomic analysis and identified differentially expressed genes (DEGs) between the white light group (the control group) and the other groups. These DEGs were enriched in the following pathways: plant-pathogen interaction, endocytosis, plant hormone signal transduction, photosynthesis-antenna proteins, photosynthesis, and circadian rhythm. We analyzed the Pearson correlation between the relative expression of the DEGs and the concentration of the key medicinal component in ARs, atractylon, and verified gene expression by RT-qPCR. The results indicated that the genes WRKY2, and MYC2, HSPs, EBF1, SAUR72, PYL4, and MKK5 of the enriched pathways were positively associated with atractylon accumulation. [ABSTRACT FROM AUTHOR]

We report the synthesis of two novel halogenated nitro-arylhimachalene derivatives: 2-bromo-3,5,5,9-tetramethyl-1-nitro-6,7,8,9-tetrahydro-5H-benzo[7]annulene (bromo-nitro-arylhimachalene) and 2-chloro-3,5,5,9-tetramethyl-1,4-dinitro-6,7,8,9-tetrahydro-5H-benzo[7]annulene (chloro-dinitro-arylhimachalene). These compounds were derived from arylhimachalene, an important sesquiterpene component of Atlas cedar essential oil, via a two-step halogenation and nitration process. Characterization was performed using 1H and 13C NMR spectrometry, complemented by X-ray structural analysis. Quantum chemical calculations employing density functional theory (DFT) with the Becke3-Lee-Yang-parr (B3LYP) functional and a 6-31++G(d,p) basis set were conducted. The optimized geometries of the synthesized compounds were consistent with X-ray structure data. Frontier molecular orbitals and molecular electrostatic potential (MEP) profiles were identified and discussed. DFT reactivity indices provided insights into the compounds' behaviors. Moreover, Hirshfeld surface and 2D fingerprint analyses revealed significant intermolecular interactions within the crystal structures, predominantly H–H and H–O contacts. Molecular docking studies demonstrate strong binding affinities of the synthesized compounds to the active site of protein 7B2W, suggesting potential therapeutic applications against various isolated smooth muscles and neurotransmitters. [ABSTRACT FROM AUTHOR]

Introduction: Oral Squamous Cell Carcinoma (OSCC) is a prevalent form of oral cancer, ranking 17th in prevalence in Indonesia. It is typically managed through surgical procedures, chemotherapy, and radiotherapy, though these interventions may adversely impact patients' quality of life. Additionally, OSCC often exhibits resistance to conventional drugs, prompting research into potential and effective anticancer therapies, particularly targeting the epidermal growth factor receptor (EGFR). Qusthul hindi (Saussurea costus), commonly known as qust, is a biopharmaceutical plant native to South Asia. It is extensively employed for medicinal purposes, especially its root extracts, known for their high concentration of sesquiterpene compounds, which demonstrate notable anticancer properties. Objectives: To predict the potential of sesquiterpene compound of qust extract (SCoQE) as anticancer therapy in inhibiting EGFR. Materials and methods: The study design is descriptive, using an in silico method involving computational prediction. It consists of several stages, including preparation, PASS prediction test, physicochemical tests, ADMET prediction, and molecular docking simulation. Results: SCoQE exhibits distinct anticancer properties against OSCC by effectively inhibiting the active site of EGFR. Additionally, SCoQE demonstrates drug-like characteristics, with a considerable likelihood (probability greater than 0.700) of acting as an anticancer agent. Furthermore, SCo-QE is anticipated to be adequately absorbed and distributed throughout the body during the initial metabolic pass, with a predicted absence of toxic effects. Conclusion: SCoQE has ability to inhibit EGFR with the most promising compound being costunolide and dehydrocostus lactone. In further studies will be carried out other comprehensive studies to mapping anticancer ability. [ABSTRACT FROM AUTHOR]

A new sesquiterpene acid, named dihydrophaseic acid A (1), along with four known organic acids, p -hydroxybenzoic acid (2), vanillic acid (3), dihydrophaseic acid (4), and 4-methylpyrazole-3-carboxylic acid (5), were obtained by isolation and purification from the ethyl acetate extract of the seeds of Phaseolus lunatus L. (Fabaceae). The structural elucidation of the new sesquiterpene acid was performed using a variety of spectroscopic methods (HRESIMS, UV, IR, 1D and 2D NMR) and ECD calculations. All compounds were evaluated for in vitro anti-inflammatory activity using mouse mononuclear macrophages cells (RAW264.7). The anti-inflammatory evaluation demonstrated that the new compound exhibited moderate NO inhibitory effect on lipopolysaccharide (LPS)-stimulated RAW264.7 cells with IC 50 value of 28.30 ± 0.76 µM, compound 5 displayed the most active inhibitory activity with an IC 50 value of 5.55 ± 0.79 µM. [Display omitted] ● A new sesquiterpene acid structurally similar to the abscisic acid metabolite was isolated from Phaseolus lunatus L.. ● All organic acids were isolated from the seeds of Phaseolus lunatus L. for the first time. ● The new sesquiterpene acid exhibited a moderate NO inhibitory effect. [ABSTRACT FROM AUTHOR]

Four undescribed sesquiterpenes, namely faberivax A-B (1 - 2) and faberine A-B (3 - 4), were isolated from the whole plant of Carpesium faberi , along with nine known sesquiterpenes (5 − 13). The structures were identified using NMR, HRESIMS, and ECD analysis, and by comparing them with literature data. To initially explore the presence of multidrug resistance (MDR) reversal activities, molecular docking was conducted to explore the binding energies and conformations between all the isolates and P-glycoprotein. The computed binding energy data suggested that six sesquiterpenes docked into the P-glycoprotein with good binding affinity as evidenced by the lower computed binding energies ranging between −7.14 to −7.85 kcal/mol. [Display omitted] • Four new sesquiterpenes were isolated from Carpesium faberi. • Their structures were confirmed by NMR data and ECD calculations. • Nine known sesquiterpenes obtained for the first time from the Carpesium genus. • The existence of multidrug resistance (MDR) reversal activity was preliminarily explored by molecular docking. [ABSTRACT FROM AUTHOR]

One previously undescribed sesquiterpene analogue, M2 (1), together with five known ones, indole-3-carboxylic acid (2), methyl 4-hydroxycinnamate (3), ergosterol peroxide (4), 6β-hydroxystigmast-4-en-3-one (5), as well as betulonic acid (6), were isolated from the EtOAc extract of the culture broth of an actinomycete Streptomyces sp. M2. The structures of all isolates were elucidated on the basis of extensive analyses of spectroscopic data and comparison with literature data. [ABSTRACT FROM AUTHOR]

Plant stress alters emissions of volatile organic compounds. However, little is known about how this could influence climate-relevant properties of secondary organic aerosol (SOA), particularly from complex mixtures such as real plant emissions. In this study, the chemical composition and viscosity were examined for SOA generated from real healthy and aphid-stressed Canary Island pine (Pinus canariensis) trees, which are commonly used for landscaping in Southern California. Healthy Canary Island pine (HCIP) and stressed Canary Island pine (SCIP) aerosols were generated in a 5 m3 environmental chamber at 35-84% relative humidity and room temperature via OH-initiated oxidation. Viscosities of the collected particles were measured using an offline poke-flow method, after conditioning the particles in a humidified air flow. SCIP particles were consistently more viscous than HCIP particles. The largest differences in particle viscosity were observed in particles conditioned at 50% relative humidity where the viscosity of SCIP particles was an order of magnitude larger than that of HCIP particles. The increased viscosity for the aphid-stressed pine tree SOA was attributed to the increased fraction of sesquiterpenes in the emission profile. The real pine SOA particles, both healthy and aphid-stressed, were more viscous than α-pinene SOA particles, demonstrating the limitation of using a single monoterpene as a model compound to predict the physicochemical properties of real biogenic SOA. However, synthetic mixtures composed of only a few major compounds present in emissions (

Sesquiterpene cyclases (STC) catalyse the cyclization of the C15 molecule farnesyl diphosphate into a vast variety of mono- or polycyclic hydrocarbons and, for a few enzymes, oxygenated structures, with diverse stereogenic centres. The huge diversity in sesquiterpene skeleton structures in nature is primarily the result of the type of cyclization driven by the STC. Despite the phenomenal impact of fungal sesquiterpenes on the ecology of fungi and their potentials for applications, the fungal sesquiterpenome is largely untapped. The identification of fungal STC is generally based on protein sequence similarity with characterized enzymes. This approach has improved our knowledge on STC in a few fungal species, but it has limited success for the discovery of distant sequences. Besides, the tools based on secondary metabolite biosynthesis gene clusters have shown poor performance for terpene cyclases. Here, we used four sets of sequences of fungal STC that catalyse four types of cyclization, and specific amino acid motives to identify phylogenetically related sequences in the genomes of basidiomycetes fungi from the order Polyporales. We validated that four STC genes newly identified from the genome sequence of Leiotrametes menziesii, each classified in a different phylogenetic clade, catalysed a predicted cyclization of farnesyl diphosphate. We built HMM models and searched STC genes in 656 fungal genomes genomes. We identified 5605 STC genes, which were classified in one of the four clades and had a predicted cyclization mechanism. We noticed that the HMM models were more accurate for the prediction of the type of cyclization catalysed by basidiomycete STC than for ascomycete STC.

(-)-Geosmin has high demand in perfumes and cosmetic products for its earthy congenial aroma. The current production of (-)-geosmin is either by distillation of sun-baked soil or by inefficient chemical synthesis because of the presence of multiple chiral centers. Fermentation processes are not viable as the titers of the Streptomyces sp. based processes are low. This work presents an alternative route by the heterologous synthesis of (-)-geosmin in Saccharomyces cerevisiae. The enzyme involved is the bifunctional geosmin synthase that catalyzes the conversion of farnesyl diphosphate to germacradienol and germacradienol to geosmin. This study evaluated the activity of many orthologs of geosmin synthase when expressed heterologously in S. cerevisiae. When the well-characterized CAB41566 from Streptomyces coelicolor origin was tested, germacradienol and germacrene D were detected but no geosmin. Bioinformatic analysis based on high/low identities to N-terminal and C-terminal domains of CAB41566 was carried out to identify different orthologs of geosmin synthase proteins from different bacterial and fungal origins. ADO68918 of Stigmatella aurantiaca origin showed the best activity among the tested orthologs, not only in terms of geosmin production but also an order of magnitude higher total abundance of the products of geosmin synthase as compared to CAB41566. This study successfully demonstrated the production of (-)-geosmin in S. cerevisiae and offers an alternative, sustainable and environment-friendly approach to producing (-)-geosmin. • Functional expression of geosmin synthase orthologs in Saccharomyces cerevisiae • ADO68918 of Stigmatella aurantiaca showed best germacradienol and geosmin synthesis • Successful production of (-)geosmin in yeast was demonstrated [ABSTRACT FROM AUTHOR]

A new bisabolane sesquiterpenoid, named calkbisabenacid (1), was isolated from the leaves of Callicarpa kwangtungensis, along with four known compounds: 5-O-coumaroylquinic acid (2), kaempferol (3), and soyasapogenol B (4). The structure of compound 1 was determined by ¹H NMR, 13C NMR, COSY, HSQC, and HMBC spectra, in combination with the HRESIMS data. The absolute configuration of C-1 in compound 1 was determined by comparing the experimental ECD spectrum with the calculated ECD spectra of the two possible stereoisomers. The known compounds were identified by comparing their NMR data with those reported in the literature. Compound 4 was isolated from this species for the first time. None of these compounds demonstrated any inhibitory effects against Staphylococcus aureus ATCC 25923. [ABSTRACT FROM AUTHOR]

An investigation of the secondary metabolites of the sea sediment-derived Penicillium sp. LPFH-ZW- 1 resulted in the identification of a new compound, named penicipeneacid (1), along with seven known compounds. The structures of these compounds were established by extensive analysis of the 1D and 2D NMR data, combined with HRESIMS data. The absolute configuration of 1 was determined by comparing the experimental and predicted ECD spectra. The bicyclo[4.1.0]heptane nucleus in compounds 1 and 2 was rarely found in nature. The known compounds were identified to be sesquicaranoic acid B (2), 9-cycloneren-3,7,11- triol (3), fumiquinazoline J (4), versiquinazoline H (5), penipurdin A (6), questinol (7), and 2-hydroxy-4- ethoxybenzoic acid (8). Compounds 4 and 7 exhibited moderate cytotoxicity against MCF-7 and K562 tumor cell lines, with IC50 values ranging from 12.6 to 37.1 μM. [ABSTRACT FROM AUTHOR]

Two new sesquiterpene glucosides, 1α,6β,9β-trihydroxy-eudesm-4(15)-en-1,6-O-β-diglucopyranoside (1) and 1α,6β,9β-trihydroxy-eudesm-3-en-1,6-O-β-diglucopyranoside (2) were obtained along with the 1α,6β,9β-trihydroxy-5,10-bis-epi-eudesm-3-en-6-O-β-D-glucopyranoside (3), chlorogenic acid (4), luteolin 7-O-rutinoside (5) and luteolin 7-O- glucoside (6) from the whole plant parts of Lecokia cretica. Their structures were determined on the basis of 1 D, 2 D NMR and HRMS analyses. The in vitro cytotoxic activity of compounds 1-3 against human lung cancer cells (A549) and normal human lung cells (BEAS-2B) was determined using the MTT colorimetric assay. All the tested eudesmane derivatives were found to be inactive. [ABSTRACT FROM AUTHOR]

Alantolactone is a eudesmane-type sesquiterpene lactone containing an α-methylene-γ-lactone moiety. Previous studies showed that alantolactone inhibits the nuclear factor κB (NF-κB) signaling pathway by targeting the inhibitor of NF-κB (IκB) kinase. However, in the present study, we demonstrated that alantolactone selectively down-regulated the expression of tumor necrosis factor (TNF) receptor 1 (TNF-R1) in human lung adenocarcinoma A549 cells. Alantolactone did not affect the expression of three adaptor proteins recruited to TNF-R1. The down-regulation of TNF-R1 expression by alantolactone was suppressed by an inhibitor of TNF-α-converting enzyme. Alantolactone increased the soluble forms of TNF-R1 that were released into the culture medium as an ectodomain. The structure–activity relationship of eight eudesmane derivatives revealed that an α-methylene-γ-lactone moiety was needed to promote TNF-R1 ectodomain shedding. In addition, parthenolide and costunolide, two sesquiterpene lactones with an α-methylene-γ-lactone moiety, increased the amount of soluble TNF-R1. Therefore, the present results demonstrate that sesquiterpene lactones with an α-methylene-γ-lactone moiety can down-regulate the expression of TNF-R1 by promoting its ectodomain shedding in A549 cells. [ABSTRACT FROM AUTHOR]

The resinous stem of Aquilaria sinensis (Lour.) Gilg is the sole legally authorized source of agarwood in China. However, whether other tissue parts can be potential substitutes for agarwood requires further investigation. In this study, we conducted metabolic analysis and transcriptome sequencing of six distinct tissues (root, stem, leaf, seed, husk, and callus) of A. sinensis to investigate the variations in metabolite distribution characteristics and transcriptome data across different tissues. A total of 331 differential metabolites were identified by chromatography–mass spectrometry (GC-MS), of which 22.96% were terpenoids. The differentially expressed genes (DEGs) in RNA sequencing were enriched in sesquiterpene synthesis via the mevalonate pathway. The present study establishes a solid foundation for exploring potential alternatives to agarwood. [ABSTRACT FROM AUTHOR]

The objective of this study was to identify the major compounds present in Cedar tar obtained by distillation of Cedrus atlantica wood from the Taza forest (Morocco) and to evaluate its antidermatophytic activity in vitro against the three strains of dermatophytes most widespread in Morocco, considered the main prevailing causes of fungal infections of the skin, hair and nails. GC/MS analysis revealed that cedar tar is composed mainly of hydrocarbon sesquiterpenes and oxygenated sesquiterpenes, with nine major compounds identified, including α-Cedrene, β-Cadinene, γ-Cadinene, β-Himachelene, α-Turmerone, β-Turmerone, Ar-tumerone, α-Atlantone and Himachalol. The evaluation of antifungal activity was carried out by the micro dilution technique. The MIC values found were 100µg/mL, 2µg/mL and 0.1µg/mL on Trichophyton rubrum, Trichophyton mentagrophytes and Microsporum canis strains respectively. The observed strong antifungal activity of cedar tar is attributed to the prevalence of oxygenated and hydrocarbon sesquiterpenes, known for their established antidermatophytic properties. This study highlights the potential of the Atlas Cedar tar as an effective antifungal agent for the treatment of superficial mycoses, particularly dermatophytoses. [ABSTRACT FROM AUTHOR]

Plant resources are used as raw materials in various industries related to humans, such as edible, medicinal, taste, and flavor industries, depending on processes such as drying, processing, and collection period. In this study, we investigated the terpene compound composition and antioxidant activity of essential oils extracted from the needles of Pinus densiflora, Pinus koraiensis, Abies holophylla, and Juniperus chinensis collected in the harvest period (February, April, July, and October) planted on the campus of Chungbuk National University. The essential oil was separated by hydrodistillation. According to the analysis results of gas chromatography–mass spectrometry, the terpene compounds changed depending on the season and tree species. The proportions of monoterpene and sesquiterpene classes in the needles of P. densiflora, P. koraiensis, A. holophylla, and J. chinensis changed depending on the harvest period. The antioxidant activity by DPPH and ABTS assays varied depending on the species and seasons, and needles harvested from P. koraiensis showed the highest activity in all harvest periods. High antioxidant activity has been confirmed even at low concentrations in pine trees, so it is expected to play a role as a natural antioxidant. Additionally, since the composition of terpene compounds varies depending on the harvesting time and species, it is expected to have various uses in the pharmaceutical, cosmetics, and food industries. [ABSTRACT FROM AUTHOR]

The yellow-flowering plant Cladanthus arabicus (L.) Cass., commonly called Arabian Cladanthus or palm springs daisy, is typical of the West Mediterranean region and is particularly abundant in Morocco. The plant is used in traditional Moroccan medicine for the treatment of diabetes and other ailments. Over the past 20 years, this abundant wild plant has been neglected from a phytochemical viewpoint. For the first time, the present review provides a survey of the pharmacological properties reported from extracts of C. arabicus and from essential oils derived from the aerial parts, mainly antimicrobial, antioxidant, and anti-inflammatory properties. The main bioactive natural products are discussed, with a focus on two rare sesquiterpenes of major interest, which are abundant in the stems and leaves: the 6,12-guaianolide cladantholide and the germacranolide sintenin. These sesquiterpene lactones and their analogues are presented to highlight their properties, extraction or total synthesis, and their therapeutic benefits. They both represent convenient biosourced precursors for the synthesis of derivatives. Sintenin may be used as a starting material for the design of hemi-synthetic germacradienolide-type costunolide or parthenolide derivatives. The 6,12-guaianolide scaffold of cladantholide offers opportunities to design novel arglabin derivatives. The therapeutic potential of the neglected and under-utilized plant Cladanthus arabicus and its original phytochemicals shall be explored further. [ABSTRACT FROM AUTHOR]

The yellow-flowering plant Cladanthus arabicus (L.) Cass., commonly called Arabian Cladanthus or palm springs daisy, is typical of the West Mediterranean region and is particularly abundant in Morocco. The plant is used in traditional Moroccan medicine for the treatment of diabetes and other ailments. Over the past 20 years, this abundant wild plant has been neglected from a phytochemical viewpoint. For the first time, the present review provides a survey of the pharmacological properties reported from extracts of C. arabicus and from essential oils derived from the aerial parts, mainly antimicrobial, antioxidant, and anti-inflammatory properties. The main bioactive natural products are discussed, with a focus on two rare sesquiterpenes of major interest, which are abundant in the stems and leaves: the 6,12-guaianolide cladantholide and the germacranolide sintenin. These sesquiterpene lactones and their analogues are presented to highlight their properties, extraction or total synthesis, and their therapeutic benefits. They both represent convenient biosourced precursors for the synthesis of derivatives. Sintenin may be used as a starting material for the design of hemi-synthetic germacradienolide-type costunolide or parthenolide derivatives. The 6,12-guaianolide scaffold of cladantholide offers opportunities to design novel arglabin derivatives. The therapeutic potential of the neglected and under-utilized plant Cladanthus arabicus and its original phytochemicals shall be explored further.

The root of Paeonia lactiflora pall. is a significant component of traditional Chinese medicine, with terpenoids and their glycosides, such as paeoniflorins, serving as key active ingredients known for their anti-inflammatory, hepatoprotective, and analgesic properties. By generating a transcriptome and functionally characterizing 32 terpene synthases (TPSs) from P. lactiflora, we successfully constructed 24 pESC-Trp-PlTPS expression vectors. Through expression in Saccharomyces cerevisiae engineered strains, we identified four mono-TPSs and five sesqui-TPSs that produce 18 compounds, including eight monoterpenes and ten sesquiterpenes in vitro. This includes a bifunctional enzyme (PlTPS22). Additionally, PlTPS21 was characterized as a pinene synthase with α-pinene as its main product. The expression pattern of PlTPS21 aligns closely with the accumulation patterns of paeoniflorins and α-pinene in the plant, suggesting that PlTPS21 is a key enzyme in the biosynthesis of paeoniflorin.

Eight new 12,8-eudesmanolide sesquiterpenes, eutypellaolides A-H (1-8), and two new eudesmane-type sesquiterpenes, eutypellaolides I-J (9-10), along with four known 12,8-eudesmanolide compounds 11-14, were isolated from the culture extract of the polar fungus Eutypella sp. D-1 by one strain many compounds (OSMAC) approach. The structures of these compounds were determined through comprehensive spectroscopic data and experimental and calculated ECD analysis. Antibacterial, immunosuppressive, and PTP1B inhibition activities of these compounds were evaluated. Compounds 1 and 11 exhibited strong inhibitory activities against Bacillus subtilis and Staphylococcus aureus, with each showing an MIC value of 2 µg/mL. Compound 9 displayed weak immunosuppressive activity against ConA-induced T-cell proliferation with an inhibitory rate of 61.7% at a concentration of 19.8 µM. Compounds 5, 11, and 14 exhibited weak PTP1B inhibition activities with IC50 values of 44.8, 43.2, and 49.5 µM, respectively. [ABSTRACT FROM AUTHOR]

One previously undescribed sesquiterpene analog, M5205 (1), together with four known analogs, betulinic acid (2), betulin (3), messagenic acid D (4), and betulonic acid (5), were isolated from the EtOAc extract of the culture broth of the actinomycete Streptomyces sp. M5205. The structures of all isolates were elucidated on the basis of extensive analyses of spectroscopic data and comparison with literature data. Their antifungal activity was also evaluated. Our results showed that 4 constituents (Compounds 1 & 3-5) possessed mild antifungal activity against Fusarium sp. LC8, Neopestalotiopsis sp. BCRC 35002, and Colletotrichum gloeosporioides BCRC 35178. It is worth mentioning that the chemical composition of the type strain Streptomyces sp. M5205 has never been studied. [Display omitted] • One diterpene, M5205 (1) was isolated from Streptomyces M5205. • 3 demonstrated the highest antifungal activity against 3 test organisms. • 1 , 4 and 5 showed different sensitivities in inhibiting the growth of test organisms. • These data suggest the potential use of compound 3 as a biocontrol agent. [ABSTRACT FROM AUTHOR]

A comprehensive study was conducted on the diversity and characteristics of five Thymus species native to Hungary, concerning frequency of occurrence, habitat preferences, essential oil content of the dried flowering shoots, and chemotype patterns determined by GC/MS. Our main aims were to provide an overview of the essential oil diversity of thyme resources and select the best genotypes with potential for cultivation and utilization. Based on the results obtained in 74 populations of 63 localities belonging to 15 regions of the Transdanubian and Northern Hungarian Mountains, considerable essential oil diversity was found. Thymus pannonicus (TPA), of generalist character, was proven to be the most frequent species (38 populations), while T. serpyllum (TSE) occurred only in two habitats. High average amounts of essential oil (EO) were shown for T. pannonicus (0.46 mL/100 g DW), T. pulegioides (TPU: 0.47 mL/100 g DW), and T. serpyllum (0.59 mL/100 g DW), while low EO accumulating ability was detected in T. glabrescens (TGL: 0.26 mL/100 g DW) and in T. praecox (TPR: 0.10 mL/100 g DW). In general, the thymol chemotype was the most frequent (34 populations), found together with the related molecules (p-cymene: 26; γ-terpinene: 15), while numerous other monoterpenes (M: geraniol: 12, linalool: 7) or sesquiterpenes (S: germacrene D: 25, β-caryophyllene: 21) were dominant, as well as combined (MS) chemotypes, which were also described in the Eos of Thymus species in Hungary. Our findings confirmed that T. pannonicus shows potential for cultivation with homogenous drug quality, adequate amounts of essential oil, and stability in EO composition. Data from original habitats also supports its high tolerance and adaptability to diverse environmental conditions, which is advantageous when facing climate change and extremities. [ABSTRACT FROM AUTHOR]

[Objective] To establish a HPLC method determinate seven sesquiterpenes in different parts of Ligularia fischeri. [Method] Chromatographic column was Kromasil C18(4. 6 mm)×250 mm, 5 μm), mobile phase was acetonitrile water (40 ∶ 60); column temperature was 35 ℃ ;detection wavelength was 240 nm; injection volume was 10 μL. [Result] The linearity of seven sesquiterpenes was good in the range of their mass concentration (R²≥0. 999 0); the average recovery rates were 95. 18%-97. 61%, RSDs were 0. 41%-1. 60%. The content of seven sesquiterpenoids detected in different parts of the root, stem and leaf of Ligularia fischeri were significantly different. The content and kinds of compounds in roots were higher than that in other parts. [Conclusion] The method was fast, simple and accurate,and can be used for the quality control of Ligularia fischeri. [ABSTRACT FROM AUTHOR]

Ferula is a genus of flowering plants known for its edible and medicinal properties. Since ancient times, many species of Ferula have been used in traditional medicine to treat various health issues across countries, such as digestive disorders, respiratory problems, and even as a remedy for headaches and toothaches. In addition, they are also used as a flavoring agent in various cuisines. As the main active ingredients in Ferula, sesquiterpenes and their derivatives, especially sesquiterpene coumarins, sesquiterpene phenylpropanoids, and sesquiterpene chromones, have attracted the attention of scientists due to the diversity of their chemical structures, as well as their extensive and promising biological properties, such as antioxidative, anti-inflammatory, antibacterial properties. However, there has not been a comprehensive review of sesquiterpenes and their derivatives from this plant. This review aims to provide an overview of the chemical structures, biosynthetic pathways, and biological properties of sesquiterpenes and sesquiterpene derivatives from Ferula, which may help guide future research directions and possible application methods for this valuable edible and medicinal plant. [ABSTRACT FROM AUTHOR]

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Previously, we reported two cytotoxic ψ-santonin–amino acid conjugates isolated from the EtOAc layer of Crossostephium chinense. However, a further phytochemical investigation seems to be required because of the few reports of similar derivatives. In this study, we targeted the 1-BuOH layer, which resulted in the isolation of seven new ψ-santonin derivatives (1–7) together with ten known compounds (8–17). The structures of 1–7 were elucidated based on spectroscopic methods, including 1D and 2D NMR experiments (1H, 13C, DEPT, COSY, HSQC, and HMBC), IR spectrum, and high-resolution electrospray ionization–mass spectrometry (HR-ESI–MS). The stereochemistry of new compounds was confirmed by NOESY and ECD calculations. All isolated compounds were evaluated by in vitro experiments for their anti-proliferative activities against Leishmania major, human lung cancer cell line A549, and Vero cells. As a result, most of the ψ-santonin derivatives, especially 1–5, showed significant cytotoxicity against L. major with a lower IC50 than the positive control we used (miltefosine). [ABSTRACT FROM AUTHOR]

Beta‐elemene, a class of sesquiterpene derived from the Chinese medicinal herb Curcuma wenyujin, is widely used in clinical medicine due to its broad‐spectrum antitumor activity. However, the unsustainable plant extraction prompted the search for environmentally friendly strategies for β‐elemene production. In this study, we designed a Yarrowia lipolytica cell factory that can continuously produce germacrene A, which is further converted into β‐elemene with 100% yield through a Cope rearrangement reaction by shifting the temperature to 250°C. First, the productivity of four plant‐derived germacrene A synthases was evaluated. After that, the metabolic flux of the precursor to germacrene A was maximized by optimizing the endogenous mevalonate pathway, inhibiting the competing squalene pathway, and expressing germacrene A synthase gene in multiple copies. Finally, the most promising strain achieved the highest β‐elemene titer reported to date with 5.08 g/L. This sustainable and green method has the potential for industrial β‐elemene production. [ABSTRACT FROM AUTHOR]

Ginger extracts (GEs) are antioxidant, antimicrobial, and anti-inflammatory. Their bioactivity can benefit foods and active packaging by extending shelf life, enhancing safety, and providing health benefits. Highly bioactive GEs are crucial to formulating potent active products and avoiding negative effects on their properties. Sesquiterpenes and phenolics are the main bioactives in ginger, but drying and extraction affect their composition. GEs are usually obtained from dry rhizomes; however, these operations have been studied independently. Therefore, a combined study of innovative drying and extraction technologies to evaluate their influence on extracts' composition will bring knowledge on how to increase the bioactivity of GEs. The effects of an emergent drying (vacuum microwave, VMD) followed by an emergent extraction (ultrasound, UAE, 20 or 80 °C) were investigated in this work. Microwave extraction (MAE) of fresh ginger was also studied. Convective oven drying and Soxhlet extraction were the references. Drying kinetics, powder color, extract composition, and antioxidant activity were studied. While MAE preserved the original composition profile, VMD combined with UAE (20 °C) produced extracts richer in phenolics (387.6 mg.GAE/g) and antioxidant activity (2100.7 mmol.Trolox/mL), with low impact in the sesquiterpenes. VMD generated shogaols by its high temperatures and facilitated extracting bioactives by destroying cellular structures and forming pores. UAE extracted these compounds selectively, released them from cell structures, and avoided losses caused by volatilization and thermal degradation. These findings have significant implications, as they provide an opportunity to obtain GE with tailored compositions that can enhance the formulation of food, active packaging, and pharmacological products. [ABSTRACT FROM AUTHOR]

This study describes the cloning, expression and functional characterization of α-humulene synthase, responsible for the formation of the key aromatic compound α-humulene in agarwood originating from Aquilaria malaccensis. The partial sesquiterpene synthase gene from the transcriptome data of A. malaccensis was utilized for full-length gene isolation via a 3′ RACE PCR. The complete gene, denoted as AmDG2, has an open reading frame (ORF) of 1671 bp and encodes for a polypeptide of 556 amino acids. In silico analysis of the protein highlighted several conserved motifs typically found in terpene synthases such as Asp-rich substrate binding (DDxxD), metal-binding residues (NSE/DTE), and cytoplasmic ER retention (RxR) motifs at their respective sites. The AmDG2 was successfully expressed in the E. coli:pET-28a(+) expression vector whereby an expected band of about 64 kDa in size was detected in the SDS-PAGE gel. In vitro enzyme assay using substrate farnesyl pyrophosphate (FPP) revealed that AmDG2 gave rise to two sesquiterpenes: α-humulene (major) and β-caryophyllene (minor), affirming its identity as α-humulene synthase. On the other hand, protein modeling performed using AlphaFold2 suggested that AmDG2 consists entirely of α-helices with short connecting loops and turns. Meanwhile, molecular docking via AutoDock Vina (Version 1.5.7) predicted that Asp307 and Asp311 act as catalytic residues in the α-humulene synthase. To our knowledge, this is the first comprehensive report on the cloning, expression and functional characterization of α-humulene synthase from agarwood originating from A. malaccensis species. These findings reveal a deeper understanding of the structure and functional properties of the α-humulene synthase and could be utilized for metabolic engineering work in the future.

Abstract Valencene is a natural sesquiterpene with desirable bioactivity and aroma, making it a valuable ingredient in the food and cosmetics industries. Traditionally, valencene was extracted from the citrus fruits, and its applications were restricted by the low concentrations in natural sources and high costs for extraction. Photosynthetic biomanufacturing represents a promising route for efficient and stable production of valencene, while cyanobacteria have been considered one of the most promising platforms regarding biotechnological routes for the direct conversion of CO2. In this work, we engineered Synechocystis sp. PCC 6803 to synthesize valencene. By introducing a heterologous valencene synthase and modifying the native MEP pathway, we obtained an efficient cyanobacterial cell factory that produced 154 mg/L valencene during a semi‐continual cultivation, with an average productivity of 4.3 mg/L/day, and the cell factory exhibited robust growth and production in non‐sterilized conditions. We also achieved the production of other sesquiterpenes including bisabolene, amorpha‐4,11‐diene, farnesene, and nerolidol by engineered cyanobacteria with enhanced MEP pathway flux, showing promising potentials as a universal chassis.

Sesquiterpenes are a large variety of terpene natural products, widely existing in plants, fungi, marine organisms, insects, and microbes. Value-added sesquiterpenes are extensively used in industries such as: food, drugs, fragrances, and fuels. With an increase in market demands and the price of sesquiterpenes, the biosynthesis of sesquiterpenes by microbial fermentation methods from renewable feedstocks is acquiring increasing attention. Synthetic biology provides robust tools of sesquiterpene production in microorganisms. This review presents a summary of metabolic engineering strategies on the hosts and pathway engineering for sesquiterpene production. Advances in synthetic biology provide new strategies on the creation of desired hosts for sesquiterpene production. Especially, metabolic engineering strategies for the production of sesquiterpenes such as: amorphadiene, farnesene, bisabolene, and caryophyllene are emphasized in: Escherichia coli, Saccharomyces cerevisiae, and other microorganisms. Challenges and future perspectives of the bioprocess for translating sesquiterpene production into practical industrial work are also discussed.

We report the synthesis of two novel halogenated nitro-arylhimachalene derivatives: 2-bromo-3,5,5,9-tetramethyl-1-nitro-6,7,8,9-tetrahydro-5H-benzo[7]annulene (bromo-nitro-arylhimachalene) and 2-chloro-3,5,5,9-tetramethyl-1,4-dinitro-6,7,8,9-tetrahydro-5H-benzo[7]annulene (chloro-dinitro-arylhimachalene). These compounds were derived from arylhimachalene, an important sesquiterpene component of Atlas cedar essential oil, via a two-step halogenation and nitration process. Characterization was performed using 1H and 13C NMR spectrometry, complemented by X-ray structural analysis. Quantum chemical calculations employing density functional theory (DFT) with the Becke3-Lee-Yang-parr (B3LYP) functional and a 6-31++G(d,p) basis set were conducted. The optimized geometries of the synthesized compounds were consistent with X-ray structure data. Frontier molecular orbitals and molecular electrostatic potential (MEP) profiles were identified and discussed. DFT reactivity indices provided insights into the compounds’ behaviors. Moreover, Hirshfeld surface and 2D fingerprint analyses revealed significant intermolecular interactions within the crystal structures, predominantly H–H and H–O contacts. Molecular docking studies demonstrate strong binding affinities of the synthesized compounds to the active site of protein 7B2W, suggesting potential therapeutic applications against various isolated smooth muscles and neurotransmitters.

The production of safe food with a little to no artificial preservatives is the main and most important challenge for the food manufacturing industry. Increasing demand of using the safe preservatives has pushed the food industry to use the herbal or natural preservatives. The essential oil of the piper species consists of complex compounds like the monoterpene that has a power in the activity of the antioxidant and antibacterial. The object of research is the essential oil of piper species like the Piper nigrum, Piper betle, Piper retrofractum, Piper caninum, and Piper cubeba. The review methodology used in this research is the PRISMA flowchart (2020). PRISMA aims to identify the quality of papers and transparency of the number of articles. The objective of this research is to summarize the research related to the chemical content of the piper essential oil, the antioxidant and anti-microbe as the potential natural preservatives. The anti-microbe activity on the piper species shows the MIC score ranging from 1.5 to 12.8 mg/mL towards the standard of bacterial preservatives in preventing pathogens in foods. The essential oil of piper species has the higher antioxidant compared to the synthetic ones, like the BHA and BHT that have the score of IC₅₀

One new sesquiterpene, (6S,7R,11S)-13-carboxy-1(10)-en-dihydroartemisinic acid (1), together with three known sesquiterpenes, ainsliaea acid B (2), mongolicumin B (3), and 11β,13-dihydroxydeacetylmatricarin (4) were isolated from Taraxacum mongolicum Hand.-Mazz. The structures were established on the basis of UV, IR, HR-ESI-MS, 1D and 2D NMR spectroscopy, ECD spectroscopy, and X-ray diffraction analysis. Compound 1 was found to have potential anti-inflammatory activity and could reduce LPS-induced NO levels in murine macrophage, with inhibitory rate of 37%. [ABSTRACT FROM AUTHOR]

Phlomis olivieri Benth. is an aromatic plant endemic to Iran belonging to the Lamiaceae family. It is used to treat pain, stomach ache and common cold in Iranian traditional medicine. P. olivieri also has valuable biological properties including antioxidant, antimicrobial and analgesic ones. This was the first study designed to assess the quality, quantity and antimicrobial activity of Phlomis olivieri Benth. essential oil (POEO). Samples were randomly collected from flowering twigs of this species in three locations between Azeran and Kamoo in Kashan, Iran at peak flowering in June 2019. Water distillation extraction was used to obtain the POEO the quantity of which was calculated by weight. Gas chromatography coupled to mass spectrometry (GC/MS) was also used for POEO qualitative analysis, which revealed its chemical compounds and their percentages. Antimicrobial activity of POEO was also determined using the agar well diffusion method. Minimum inhibitory concentration (MIC) and minimum bactericidal/fungicidal concentration (MBC/MFC) were also measured using the broth microdilution method. The results of the quantitative and qualitative analysis showed that the POEO yield was ~ 0.2292% and its main chemical compounds included the sesquiterpenes germacrene D (26.43%), β-caryophyllene (20.72%), elixene (6.58%), β-trans-farnesene (6.17%), β-Cyclogermacrane (5.04%), germacrene B (4.73%), α-humulene (4.22%), and monoterpene α-pinene (3.22%). The agar diffusion method demonstrated the highest antimicrobial activity of POEO (MIC ~ 14.50 mm) was against the Gram-positive species Streptococcus pyogenes. The POEO also showed the strongest inhibitory and lethal activity against the gram-negative bacterial species Pseudomonas aeruginosa (MIC < 62.50 μg/mL) and S. paratyphi-A (MIC < 62.50 μg/mL and MBC = 125 μg/mL), and fungal species Candida albicans (MIC and MBC = 250 μg/mL) as compared to control-positive antibiotics. Therefore, POEO is a valuable natural alternative rich in sesquiterpenes with strong antimicrobial and antifungal activities against some fungal and bacterial strains. It can also be used in the pharmaceutical, food and cosmetic industries. [ABSTRACT FROM AUTHOR]

Protoilludene-type sesquiterpene aryl esters are a unique and very diverse compound class that were exclusively isolated from members of the genus Armillaria (Agaricomycetes, Physalacriaceae) up to this point. Herein, we describe the isolation and structural characterization of 5′-O-methyl-14-hydroxyarmillane (1), a new armillane-type derivative, that was obtained from submerged cultures of Guyanagaster necrorhiza (CBS 138623) together with the known congeners melleolide G (2), melleolide B (3), and 10-dehydroxy-melleolide B (4). ROESY data and coupling constants assigned the relative configurations of 1, while common absolute configurations were confirmed from comparison of its ECD spectrum to the one of 10-hydroxy-5′-methoxy-6′-chloroarmillane (5). Additionally, the configuration of melleolide G (2) was revised based on observed ROESY correlations. It is the first time that protoilludene-type sesquiterpene aryl esters were isolated from another genus, namely, Guyanagaster, that is closely related to Armillaria. 1–4 were evaluated for their biological activities in a serial dilution assay against several yeast, fungi, and bacteria, as well as in a cytotoxicity assay against different cell lines. Compound 4 was moderately active against Bacillus subtilis, Staphylococcus aureus, and Mucor hiemalis. Furthermore, 1, 3, and 4 showed weak cytotoxic effects against the mouse fibroblast cell line L929 and the cervix carcinoma cell line KB3.1. [ABSTRACT FROM AUTHOR]

A new sesquiterpene (Prosoterpene, 1) and eleven reported compounds (2–12) of several classes, such as flavonoids, alkaloids, phenolic acids, and long-chain alcohols, were isolated from the BuOH extract of Prosopis africana (Guill. & Perr.) Taub. Compounds 2–10 were reported for the first time from this plant. Isomers 11 and 12 were separated for the first time. Extensive spectroscopic techniques and literature comparisons were used to characterise their structures. Furthermore, compounds 3, 5–8, and 10–12 were performed for anti-glycation and cytotoxicity activities. Compound 3 (quercetin-3-O-α-L-rhamnoside) exhibited moderate anti-glycation activity. All tested compounds were non-cytotoxic against MCF-7 (breast cancer), NCI-H460 (lung cancer), Hela (cervical cancer), and BJ (normal human fibroblast) cell lines. [ABSTRACT FROM AUTHOR]

Sixteen conjugates of dihydroartemisinin and zerumbone with 2-mercapto-1,3,4-oxadiazoles were synthesized and structurally elucidated by ID NMR, 2D NMR, and HRMS spectra. The cytotoxic screening results showed that all the conjugates of dihydroartemisinin with 2-mercapto-1,3,4-oxadiazoles (19a-h) exhibited cytotoxic activity against two human cancer cell lines, HepG2 and LU-I, with the IC50 values ranging from 2.22 to 40.69 µM. Among dihydroartemisinin conjugates, conjugate 19b displayed the strongest activity against both HepG2 and LU-I cell lines, with the IC50 values of 3.49 and 2.22 µM, respectively. The zerumbone conjugates (20a-h) expressed their cytotoxic activity stronger than that of 19a-h series, with IC50 values ranging from 1.54 to 2.00 µM. In addition, all 16 compounds exhibited an impressively inhibitory effect against EGFR tyrosine kinase with binding affinities ranging from -8.61 to -10.2 kcal/mol, higher than that of the erlotinib drug (-7.50 kcal/mol), a co-crystallized inhibitor of EGFR receptor. Both conjugates ( 19a and 20a) containing the 2-hydroxyphenyl-2mercapto-1,3,4-oxadiazole moiety had the best binding energies (-10.2 and -9.494 kcal/mol, respectively) on the EGFR tyrosine kinase. Furthermore, the potential interactions and binding patterns between the compounds and the relevant amino acid residues revealed the most significant contribution to amplifying their efficacy against this protein, according to docking studies, which identified both hydrogen bonds and hydrophobic contacts at the active site of the EGFR protein. [ABSTRACT FROM AUTHOR]

Valencene is a natural sesquiterpene with desirable bioactivity and aroma, making it a valuable ingredient in the food and cosmetics industries. Traditionally, valencene was extracted from the citrus fruits, and its applications were restricted by the low concentrations in natural sources and high costs for extraction. Photosynthetic biomanufacturing represents a promising route for efficient and stable production of valencene, while cyanobacteria have been considered one of the most promising platforms regarding biotechnological routes for the direct conversion of CO2. In this work, we engineered Synechocystis sp. PCC 6803 to synthesize valencene. By introducing a heterologous valencene synthase and modifying the native MEP pathway, we obtained an efficient cyanobacterial cell factory that produced 154 mg/L valencene during a semi‐continual cultivation, with an average productivity of 4.3 mg/L/day, and the cell factory exhibited robust growth and production in non‐sterilized conditions. We also achieved the production of other sesquiterpenes including bisabolene, amorpha‐4,11‐diene, farnesene, and nerolidol by engineered cyanobacteria with enhanced MEP pathway flux, showing promising potentials as a universal chassis. [ABSTRACT FROM AUTHOR]