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We report the helix‐sense‐selective memory polymerization (HSMP) of achiral biphenylylacetylenes bearing carboxy and amino pendant groups in the presence of basic and acidic chiral guests in water, respectively. The HSMP proceeds in a highly helix‐sense‐selective manner driven by noncovalent chiral ionic interactions between the monomers and guests under kinetic control, producing the one‐handed helical polymers with a static memory of helicity in one‐pot during the polymerization in a very short time, accompanied by amplification of asymmetry. The carboxy‐bound helicity‐memorized polymer self‐assembles into a cholesteric liquid crystal in concentrated water, in which a variety of basic achiral fluorophores further co‐assembles to form supramolecular helical aggregates that exhibit an induced circularly polarized luminescence in a color tunable manner. [ABSTRACT FROM AUTHOR]

To explore the chirality induction and switching of topological chirality, poly[2]catenanes composed of helical poly(phenylacetylenes) (PPAs) main chain and topologically chiral [2]catenane pendants are described for the first time. These poly[2]catenanes with optically active [2]catenanes on side chains were synthesized by polymerization of enantiomerically pure topologically chiral [2]catenanes with ethynyl polymerization site and/or point chiral moiety. The chirality information of [2]catenane pendants was successfully transferred to the main chain of polyene backbones, leading to preferred‐handed helical conformations, while the introduction of point chiral units has negligible effect on the overall helices. More interestingly, attributed to unique dynamic feature of the [2]catenane pendants, these polymers revealed dynamic response behaviors to solvents, temperature, and sodium ions, resulting in the fully reversible switching on/off of the chirality induction. This work provides not only new design strategy for novel chiroptical switches with topologically chiral molecules but also novel platforms for the development of smart chiral materials. [ABSTRACT FROM AUTHOR]

Human DNA topoisomerase I (Topo I) is an essential enzyme in regulating DNA supercoiling during transcription and replication, and it is an important therapeutic target for anti-tumor agents. Bidens pilosa L. is a medicinal herb that is used as a folk medicine for cancers in China. A new flavonoid (1) and a new polyacetylene (20), along with eighteen flavonoids (2–19) and nine polyacetylenes (21–29), were isolated and identified from the methanol extract of the whole plant of B. pilosa, and some of the compounds (4, 5, 6 and 7) exhibited potent cytotoxicity against a panel of five human cancer cell lines. The DNA relaxation assay revealed that some flavonoids and polyacetylenes exerted inhibitory activities on human DNA Topo I, among them compounds 1, 2, 5, 6, 7, 8, 15, 19, 20, 22, and 24 were the most active ones, with IC50 values of 393.5, 328.98, 145.57, 239.27, 224.38, 189.84, 89.91, 47.5, 301.32, 178.03, and 218.27 μM, respectively. The structure–activity analysis of flavonoids was performed according to the results from the Topo I inhibition assay. The DNA content analysis revealed that 5, 6, and 7 potently arrested cell cycle at the G1/S and G2/M phases in human colon cancer cell DLD-1 depending on the concentration of the inhibitors. The levels of protein expression related to the G1/S and G2/M cell cycle checkpoints were in accordance with the results from the DNA content analysis. These findings suggest that flavonoids are one of the key active ingredients accounting for the anti-tumor effect of B. pilosa. [ABSTRACT FROM AUTHOR]

Ericameria nauseosa (Pall. ex Pursh) G.L. Nesom & G.I. Baird) is used in traditional medicine to treat various diseases; however, little is known about the immunomodulatory activity of essential oil from this plant. Thus, we isolated essential oil from the aerial parts of E. nauseosa and evaluated their chemical composition and biological activity. Compositional analysis of E. nauseosa essential oil revealed that the main (>2%) components were γ-decalactone (13.3%), cryptone (9.4%), terpinen-4-ol (9.3%), (E)-methyl cinnamate (6.0%), T-cadinol (4.7%), spathulenol (3.6%), 8Z-2,3-dihydromatricaria ester (3.1%), β-phellandrene (3.0%), p-cymen-8-ol (2.2%), 3-ethoxy-2-cycloocten-1-one (2.2%), and trans-p-menth-2-en-1-ol (2.1%). Distinctive features were the lactones (up to 15%) and polyacetylenes (up to 3.1%), including (2Z,8Z)-matricaria ester and 8Z-2,3-dihydromatricaria ester. A comparison with other reported E. nauseosa essential oil samples showed that our samples were distinct from those collected in other areas of the country; however, they did have the most similarity to one sample collected in North Central Utah. Pharmacological studies showed that E. nauseosa essential oil activated human neutrophil Ca2+ influx, which desensitized these cells to subsequent agonist-induced functional responses. Based on our previously reported data that nerolidol, β-pinene, spathulenol, sabinene, and γ-terpinene were active in human neutrophils, these compounds are the most likely constituents contributing to this immunomodulatory activity. However, the relatively high amount of polyacetylenes may also contribute, as these compounds have been characterized as potent immunomodulators. [ABSTRACT FROM AUTHOR]

Codonopsis radix is the dried root of C. pilosula (Franch.) Nannf., C. pilosula Nannf. var. modesta (Nannf.) L. T. Shen, or C. tangshen Oliv., constitutes a botanical medicine with a profound historical lineage. It encompasses an array of bioactive constituents, including polyacetylenes, phenylpropanoids, alkaloids, triterpenoids, and polysaccharides, conferring upon it substantial medicinal and edible values. Consequently, it has garnered widespread attention from numerous scholars. In recent years, driven by advancements in modern traditional Chinese medicine, considerable strides have been taken in exploring resources utilization, traditional processing, quality evaluation and polysaccharide research of Codonopsis radix. However, there is a lack of systematic and comprehensive reporting on these research results. This paper provides a summary of recent advances in Codonopsis research, identifies existing issues in Codonopsis studies, and offers insights into future research directions. The aim is to provide insights and literature support for forthcoming investigations into Codonopsis. [ABSTRACT FROM AUTHOR]

A phytochemical investigation of Bidens procera L.C.Xu ex X.W.Zheng afforded two novel polyacetylenes, tridecane-2E-monoene-4,6,8-triyntylen-1,13-diol-12-O-β-glucoside (1) and tetradecane-2E,8E-diene-4,6-diyne-1,14-diol-13-O-β-glucoside (2), together with ten known compounds (3 − 12). Their chemical structures were elucidated by NMR and MS spectrums as well as the comparison of the published data. Furthermore, the chemotaxonomy of the yielded compounds was also discussed. [ABSTRACT FROM AUTHOR]

A new generation of soluble phenothiazinyl merocyanine substituted polyacetylenes can be readily synthesized by rhodium‐catalyzed polymerization of the corresponding 3‐ethynyl phenothiazines, accessible by Sonogashira coupling and Knoevenagel condensation. UV/Vis and fluorescence spectroscopy of 7‐acceptor‐substituted phenothiazinyl polyacetylenes reveal that these polyacetylenes with conjugatively ligated merocyanines are luminescent in solution with positive emission solvatochromism and, in some cases, with distinct solid‐state luminescence. [ABSTRACT FROM AUTHOR]

Sensory parameters as well as the volatile and non-volatile compound profiles of sixteen carrot cultivars were recorded to obtain insight into consumer preference decisions. The sensory test was carried out with a consumer panel of 88 untrained testers allowing a clear acceptance-based differentiation of the cultivars. Five individual sensory characters (sweetness, overall aroma, bitterness, astringency and off-flavor) supported this discrimination. Chemical analyses of volatile organic compounds, polyacetylenes, phenylpropanoids and sugars enabled us to correlate the influence of these ingredients on sensory perception. Higher concentrations of α-pinene, hexanal, styrene and acetophenone correlated with a better acceptance, as well as sweetness and overall aroma perception. In contrast, a low acceptance as well as a stronger perception of bitterness, astringency and off-flavor correlated with enhanced concentrations of camphene, bornylacetate, borneol, myristicine, falcarindiol, falcarindiol-3-acetate, laserin and epilaserin. The present study should support the development of new breeding strategies for carrot cultivars that better satisfy consumer demands. [ABSTRACT FROM AUTHOR]

Anisotropic NMR spectroscopy, revealing residual dipolar couplings (RDCs) and residual chemical shift anisotropies (RCSAs) has emerged as a powerful tool to determine the configurations of synthetic and complex natural compounds. The deduction of the absolute in addition to the relative configuration is one of the primary goals in the field. Therefore, the investigation of the enantiodiscriminating capabilities of chiral alignment media becomes essential. While RDCs and RCSAs are now used for the determination of the relative configuration routinely, RCSAs have not been measured in chiral alignment media such as chiral liquid crystals. Herein, we present this application by measuring RCSAs for chiral analytes such as indanol and isopinocampheol in the lyotropic liquid crystalline phase of an L‐valine derived helically chiral polyacetylenes. We have also demonstrated that a single 1D 13C−{1H} NMR spectrum suffices to get the RCSAs circumventing the necessity to acquire two spectra at two alignment conditions. [ABSTRACT FROM AUTHOR]

A series of poly(biarylylacetylene)s (PBAs) bearing axially‐chiral (S)‐and (R)‐pyridyl‐N‐oxide residues with a methoxy, propoxy, or acetyloxy substituent at the 3‐position of the biaryl units was synthesized. All the PBAs formed a preferred‐handed helix, while the helical sense preference was varied depending on the substituents despite the same twist‐sense of the biaryl units. Among them, the propoxy‐bound helical PBA showed an exceptionally high chiral recognition ability as a chiral stationary phase (CSP) for high‐performance liquid chromatography (HPLC) and efficiently resolved not only various chiral aromatic alcohols, but also a variety of chiral aliphatic alcohols; the latter still remains difficult to resolve by commercially‐available CSPs in HPLC. Such practically‐useful both handed helical PBA‐based CSPs can be produced from the racemic PBA composed of fully racemic monomer units through deracemization of the biaryl units with a chiral alcohol. [ABSTRACT FROM AUTHOR]

Centella asiatica (L.) Urban is an herbaceous perennial plant of the Apiaceae family that has diverse medicinal uses. Its active components are saponin, phenolics, and polyacetylenes. Plant cell cultures have been exploited for the efficient production of metabolites with pharmacological activity. In this work, we prepared adventitious root cultures of C. asiatica and analyzed their content and biological activity. Adventitious root extracts were found to increase glucose uptake by differentiated L6 skeletal muscle cells and to be more efficient than the extract of whole plants. Chromatographic fractionation of the extracts from adventitious roots of C. asiatica led to the isolation of two known polyacetylenes, araliadiol (1) and 8-acetoxy-1,9-pentadecadiene-4,6-diyn-3-ol (2), in addition to a new polyacetylene, which we have named centellidiol (3). All the three polyacetylenes stimulated glucose uptake in a dose-dependent manner. The methanol extract of adventitious roots contained 0.53% and 0.82% of compounds 1 and 2 , respectively, which are values that were 15 and 21 times higher that are found in mother plants. We therefore suggest that the high content of these polyacetylenes contributes to the high efficacy of C. asiatica adventitious root cultures. Overall, adventitious root cultures of C. asiatica can be part of a secure supply of effective ingredients including polyacetylenes. • Adventitious roots of C. asiatica increased glucose uptake more efficiently than original plants. • One new polyacetylene, named centellidiol (3), and two known ones (1 - 3) were isolated. • Three polyacetylenes stimulated glucose uptake in a dose-dependent manner. • Extract of adventitious roots contained 0.53% and 0.82% of polyacetylenes 1 and 2. • High content of polyacetylenes contributed to the efficacy of C. asiatica adventitious roots. [ABSTRACT FROM AUTHOR]

A series of novel biphenylylacetylene (BPA)‐based chiral/achiral copolymers bearing a small amount of configurationally labile optically active [5]helicene pendants (5, 10, and 20 mol%) introduced at the 4′‐position of the biphenyl units was synthesized. An almost fully right (P)‐handed helical copolymer was obtained when copolymerized with 10 mol% of the (M)‐[5]helicene‐bound BPA monomer, indicative of a very strong sergeants and soldiers effect. The (M)‐helicene units of the copolymers are configurationally labile and gradually racemized over time. However, the copolymer with 10 mol% of the (M)‐[5]helicene‐bound BPA mostly maintained its preferred‐handed helicity even after the pendant helicene units were completely racemized, which can be ascribed to the static memory of the main‐chain helicity stabilized by the bulky yet racemic helicene units. Hence, the helicity memory of the corresponding helicene‐free homopolymer was lost rapidly. For comparison, an optically inactive copolymer containing 10 mol% of the racemic [5]helicene units was also prepared, and noncovalent helicity induction and subsequent memory of the helicity as well as its helix‐memory stability were investigated. [ABSTRACT FROM AUTHOR]

We report the unprecedented sergeants and soldiers (S&S)‐type remote control of one‐handed helicity in copolymers of chiral/achiral biphenylylacetylenes bearing amphiphilic oligo(ethylene glycol) (OEG) side chains. A small amount of chiral binaphthyl residues (≤10 mol %) introduced at the terminal of the achiral OEG spacers as many as 80 bonds away from the polymer backbones induced a complete one‐handed helix in water through preferential intramolecular encapsulation of the binaphthyl groups within a cavity of the copolymers. A fully one‐handed helix can be induced virtually independent of the OEG spacer length and concentrations. At a specific spacer length, however, its helix‐sense was inverted. The copolymers also form an excess one‐handed helix in organic solvents in an OEG spacer‐length dependent manner, yet far from the polymer backbones. We show the superiority of the present covalent‐bond driven S&S‐type remote helicity control over the corresponding noncovalent helicity induction approach. [ABSTRACT FROM AUTHOR]

Diverse secondary metabolites are biosynthesized by plants via various enzymatic cascades. These have the capacity to interact with various human receptors, particularly enzymes implicated in the etiology of several diseases. The n-hexane fraction of the whole plant extract of the wild edible plant, Launaea capitata (Spreng.) Dandy was purified by column chromatography. Five polyacetylene derivatives were identified, including (3S,8E)-deca-8-en-4,6-diyne-1,3-diol (1A), (3S)-deca-4,6,8-triyne-1,3-diol (1B), (3S)-(6E,12E)-tetradecadiene-8,10-diyne-1,3-diol (2), bidensyneoside (3), and (3S)-(6E,12E)-tetradecadiene-8,10-diyne-1-ol-3-O-β-D-glucopyranoside (4). These compounds were investigated for their in vitro inhibitory activity against enzymes involved in neuroinflammatory disorders, including cyclooxygenase-2 (COX-2), 5-lipoxygenase (5-LOX), and butyrylcholinesterase (BchE) enzymes. All isolates recorded weak–moderate activities against COX-2. However, the polyacetylene glycoside (4) showed dual inhibition against BchE (IC50 14.77 ± 1.55 μM) and 5-LOX (IC50 34.59 ± 4.26 μM). Molecular docking experiments were conducted to explain these results, which showed that compound 4 exhibited greater binding affinity to 5-LOX (−8.132 kcal/mol) compared to the cocrystallized ligand (−6.218 kcal/mol). Similarly, 4 showed a good binding affinity to BchE (−7.305 kcal/mol), which was comparable to the cocrystallized ligand (−8.049 kcal/mol). Simultaneous docking was used to study the combinatorial affinity of the unresolved mixture 1A/1B to the active sites of the tested enzymes. Generally, the individual molecules showed lower docking scores against all the investigated targets compared to their combination, which was consistent with the in vitro results. This study demonstrated that the presence of a sugar moiety (in 3 and 4) resulted in dual inhibition of 5-LOX and BchE enzymes compared to their free polyacetylenes analogs. Thus, polyacetylene glycosides could be suggested as potential leads for developing new inhibitors against the enzymes involved in neuroinflammation. [ABSTRACT FROM AUTHOR]

The antimicrobial activity of native antimicrobial peptides (AMPs) is often attributed to their helical structure, but the effectiveness of synthetic mimics with dynamic helical conformations, such as antimicrobial cationic polymers (ACPs), has not been well studied. Herein we demonstrate the antimicrobial activity of pyrrolidinium-pendant polyacetylenes (PAs) with dynamic helical conformations. The PAs exhibit fast and efficient antimicrobial activity against a wide range of pathogens, with low toxicity to mammalian cells and minimal risk of antibiotic resistance. In addition, the full-thickness wound infection model in mice has demonstrated the favorable biocompatibility and effective in vivo antibacterial capabilities of these PAs. Our data suggest that the dynamic helical structure of these PAs allows them to adapt and form pores in the bacterial membrane upon interaction, leading to their potent antimicrobial activity. This work investigated the antibacterial mechanism of dynamic helical ACPs, which provides valuable guidance for the rational design of high-performance antimicrobial agents. Our study represents a significant contribution to the literature on antimicrobial cationic polymers (ACPs) as alternatives to antibiotics. Through a systematic investigation of the role of dynamic helical conformation in polyacetylenes (PAs) and the use of PAs with adaptive structure for the first time, we have provided valuable insights into the bacterial membrane action and killing mechanisms of these polymers. The results of our study, including fast killing rates and minimum inhibitory concentrations as low as 4–16 µg/mL against a broad range of pathogens and strong in vivo antibacterial activity, demonstrate the potential of these ACPs as high-performance antimicrobials. Our findings may guide the design of future ACPs with enhanced antimicrobial activity. [Display omitted] [ABSTRACT FROM AUTHOR]

As a low energy consumption, simple operation and environmentally friendly separation method, membrane separation has attracted extensive attention. Therefore, researchers have designed and synthesized various types of separation membrane, such as metal organic framework (MOF), covalent organic framework (COF), polymer of intrinsic micro-porosity (PIM) and mixed matrix membranes. Some substituted polyacetylenes have distorted structures and formed micropores due to the existence of rigid main chains and substituted side groups, which can be applied to the field of membrane separation. This article mainly introduces the development and application of substituted polyacetylenes in gas separation and liquid separation based on membrane technology. [ABSTRACT FROM AUTHOR]

Polyacetylene phytochemicals are emerging as potentially responsible for the chemoprotective effects of consuming apiaceous vegetables. There is some evidence suggesting that polyacetylenes (PAs) impact carcinogenesis by influencing a wide variety of signalling pathways, which are important in regulating inflammation, apoptosis, cell cycle regulation, etc. Studies have shown a correlation between human dietary intake of PA-rich vegetables with a reduced risk of inflammation and cancer. PA supplementation can influence cell growth, gene expression and immunological responses, and has been shown to reduce the tumour number in rat and mouse models. Cancer chemoprevention by dietary PAs involves several mechanisms, including effects on inflammatory cytokines, the NF-κB pathway, antioxidant response elements, unfolded protein response (UPR) pathway, growth factor signalling, cell cycle progression and apoptosis. This review summarises the published research on falcarinol-type PA compounds and their mechanisms of action regarding cancer chemoprevention and also identifies some gaps in our current understanding of the health benefits of these PAs. [ABSTRACT FROM AUTHOR]

Two types of disubstituted polyacetylenes were synthesized and these polyacetylenes exhibited both liquid crystallinity and luminescence. First, a simple disubstituted polyacetylene with short alkyl chains was synthesized by one-step reaction. The disubstituted polyacetylene derivative showed high molecular weight and high crystallinity. Next, a disubstituted polyacetylene derivative having long alkyl chains with photo-cross-linking of liquid crystal domains under visible light was prepared via multi-step reaction. Both the polymers showed good solubility. The polymers exhibited lyotropic liquid crystallinity, a smectic phase, and liquid crystal concentration chromism as a function of color change depends on concentration in solution. The polymers were oriented under a magnetic field. Characterization of the disubstituted polyacetylenes was carried out with nuclear magnetic resonance spectroscopy, gel permeation chromatography, infrared spectroscopy, UV–vis absorption spectroscopy, fluorescence spectroscopy, and polarizing optical microscopy observations. Magnetic orientation in evaporation process via formation of lyotropic liquid crystal for obtaining uniaxial domain structure was performed. [ABSTRACT FROM AUTHOR]

Two series of hyper-cross-linked microporous polyacetylene networks containing either -[CH=C(CH=O)]- or -[CH=C(CH2OH)]- monomeric units are reported. Networks are prepared by chain-growth copolymerization of acetal-protected propargyl aldehyde and acetal-protected propargyl alcohol with a 1,3,5-triethynylbenzene cross-linker followed by hydrolytic deprotection/detemplating. Deprotection not only liberates reactive CH=O and CH2OH groups in the networks but also modifies the texture of the networks towards higher microporosity and higher specific surface area. The final networks with CH=O and CH2OH groups attached directly to the polyene main chains of the networks have a specific surface area from 400 to 800 m2/g and contain functional groups in a high amount, up to 9.6 mmol/g. The CH=O and CH2OH groups in the networks serve as active centres for the reversible capture of CO2 and water vapour. The water vapour capture capacities of the networks (up to 445 mg/g at 297 K) are among the highest values reported for porous polymers, making these materials promising for cyclic water harvesting from the air. Covalent modification of the networks with (R)-(+)-3-aminopyrrolidine and (S)-(+)-2-methylbutyric acid enables the preparation of porous chiral networks and shows networks with CH=O and CH2OH groups as reactive supports suitable for the anchoring of various functional molecules. [ABSTRACT FROM AUTHOR]

Conjugated polymers (CPs) are electronic materials which always attract the joint attention of synthetic chemistry, physics, and engineering. The present article deals with "classical" CPs such as polyacetylenes and polyarylenes, and also with more sophisticated cases such as ladder polymers and graphene nanoribbons. CPs exhibit a wide variety of fascinating electrical and optical properties which qualify them as active components of devices. Their performance, however, is shown to sensitively depend upon structural perfection and purity as well as on the thin‐film morphology, which is also influenced by processing procedures. Nowadays, the need for innovative energy technologies and sustainable materials and processes as well as the emerging new opportunities of quantum technologies, are adding further momentum to CP research. [ABSTRACT FROM AUTHOR]

A prospectively followed Danish cohort of 55,756 citizens with an observation time upwards of 25 years was investigated for association between eating raw carrots on a regular basis and developing various adenocarcinoma-dominant cancers and leukemia. Mean age at inclusion was 56.2 years (SD 4.4 years), and 52% were females. A dose-dependent reduction in incidence was seen for cancer of the lung (HR 0.76, CI95% 0.66; 0.87) and pancreas (HR 0.79, CI95% 0.61; 1.03), as well as leukemia (HR 0.91, CI95% 0.68; 1.21). Only for lung cancer was the association significant. In the case of pancreatic cancer, a possible type 1 error was present due to a low number of cancers. In cases of breast and prostate cancer, no association and no dose response were demonstrated. The association seen for lung and pancreatic cancer parallels that earlier demonstrated for large bowel cancer and indicates a cancer-protective effect from daily intake of raw carrots not limited to gastrointestinal adenocarcinomas. Processed carrots exhibited no effect. The preventive effect could be due to the polyacetylenic compounds falcarinol and falcarindiol in carrots, whereas carotene may not have an effect. The polyacetylenes are inactivated by heating, supporting our findings that only raw carrot intake has an effect. Indirect evidence for the cancer preventive effect of carrots in humans has reached a level where a prospective human trial is now timely. [ABSTRACT FROM AUTHOR]

In vitro studies and animal studies have shown that chemical compounds contained in carrots, such as falcarinol and falcarindiol, can prevent inflammation. The present study was designed to test whether the oral intake of carrot juice containing falcarinol and falcarindiol affects the activity of cyclooxygenase (COX) enzymes and the secretion of inflammatory cytokines in human blood. Carrot juice (500 mL) was administered orally to healthy volunteers, and blood samples were drawn before and 1 h after juice intake at the time point when peak concentrations of falcarinol and falcariondiol have been shown in the blood. The blood samples were divided, and one sample was allowed to coagulate for 1 h at room temperature before analyzing the synthesis of thromboxane B2 (TBX2) by the COX1 enzyme using an enzyme linked immunosorbent assay (ELISA). The other blood samples were stimulated ex vivo with lipopolysaccharide and incubated at 37 °C for 24 h. The ELISA and cytokine multiplex analysis assessed the levels of COX-2-induced prostaglandin E2 (PGE2) and inflammatory markers interleukin (IL) 1α, IL1β, IL6, IL16, and tumor necrosis factor α (TNFα). Inflammatory cytokines such as IL1α and IL16 were significantly reduced in the LPS stimulated blood samples with higher concentrations of falcarinol and falcariondiol compared to the control samples taken before the intake of carrot juice. The levels of TBX2, PGE2, IL1β, IL6, and TNFα were not affected by the carrot juice intake blood samples not stimulated with LPS. In conclusion, carrot juice rich in the polyacetylens falcarinol and falcarindiol affects blood leukocytes, priming them to better cope with inflammatory conditions, evident by the reduced secretion of the proinflammatory cytokines IL1α and IL16. [ABSTRACT FROM AUTHOR]

Sensory parameters as well as the volatile and non-volatile compound profiles of sixteen carrot cultivars were recorded to obtain insight into consumer preference decisions. The sensory test was carried out with a consumer panel of 88 untrained testers allowing a clear acceptance-based differentiation of the cultivars. Five individual sensory characters (sweetness, overall aroma, bitterness, astringency and off-flavor) supported this discrimination. Chemical analyses of volatile organic compounds, polyacetylenes, phenylpropanoids and sugars enabled us to correlate the influence of these ingredients on sensory perception. Higher concentrations of α-pinene, hexanal, styrene and acetophenone correlated with a better acceptance, as well as sweetness and overall aroma perception. In contrast, a low acceptance as well as a stronger perception of bitterness, astringency and off-flavor correlated with enhanced concentrations of camphene, bornylacetate, borneol, myristicine, falcarindiol, falcarindiol-3-acetate, laserin and epilaserin. The present study should support the development of new breeding strategies for carrot cultivars that better satisfy consumer demands.

The developments of pure organic room-temperature phosphorescence (RTP) materials with circularly polarized luminescence (CPL) have significantly facilitated the future integration and systemization of luminescent material in fundamental science and technological applications. Here, a type of photoinduced circularly polarized RTP materials are constructed by homogeneously dispersing phosphorescent chiral helical substituted polyacetylenes into a processable poly(methyl methacrylate) (PMMA) matrix. These substituted polyacetylenes play vital roles in the propagation of CPL and present prominently optical characteristics with high absorption and luminescent dissymmetric factors up to 0.029 (gabs) and 0.019 (glum). The oxygen consumption properties of the films under UV light irradiation endow materials with dynamic chiro-optical functionality, which can leverage of light to precisely control and manipulate the circularly polarized RTP properties with the remarkable advantages of being contactless, wireless and fatigue-resistant. Significantly, the distinct materials with dynamic properties can be used as anti-counterfeiting materials involving photoprogrammability. 'Pure organic room-temperature phosphorescence (RTP) materials with circularly polarized luminescence (CPL) gained increasing interest. Here, the authors propose a photoinduced circularly polarized RTP material by homogeneously dispersing phosphorescent chiral polyacetylenes into a processable polymer matrix. [ABSTRACT FROM AUTHOR]

A new polyacetylenic glucoside together with three known compounds were isolated from the whole herb of Bidens pilosa L. The structure elucidation of these four compounds was employed by combining NMR and HR-MS data as 4-O-β-D-glucopyranosyloxy-1-hydroxy- 6-(E)-tetradecene-8,10,12-triyne (1), 3-O-β-D-glucopyranosyloxy-1-hydroxy-6-(E)-tetradec- ene-8,10,12-triyne (2), 2-O-β-D-glucopyranosyloxy-1-hydroxy-5-(E)-tetradecene-7,9,11-triy- ne (3) and icthyothereol acetate (4). Additionally, bioactivity study showed that these compounds have potential anti-inflammatory activity. This study has certain guiding significance for the development and utilisation of polyacetylene compounds in Bidens pilosa L. [ABSTRACT FROM AUTHOR]

Cyclopolymerization is a powerful method for synthesizing polyacetylenes containing four‐ to seven‐membered rings. However, the structure of the repeat unit only consists of mono‐cycloalkene due to the single cyclization of diyne monomers. Herein, we demonstrate a novel cascade cyclopolymerization to synthesize polyacetylenes containing fused bicyclic rings from triyne monomers containing bulky dendrons via sequential cascade ring‐closing metathesis. These dendrons provided solubility and stability to the rigid bicyclic polyacetylene backbone. In addition, we controlled the regioselectivity of the catalyst approach by altering its structure and synthesized polymers containing fused bicyclo[4,3,0] or [4,4,0] rings with high molecular weights of up to 120 kg mol−1. Interestingly, the resulting polymers showed narrower band gaps (down to 1.6 eV) than polymers with mono‐cycloalkene repeat units due to the planarization of the conjugated segment resulting from the fused bicyclic structure. [ABSTRACT FROM AUTHOR]

Although C17 polyacetylenes from Panax ginseng exhibit cytotoxic properties against various tumor cells, there have been few experiments on epithelial ovarian carcinoma cells. This study aimed to investigate the cytotoxic effects of C17 polyacetylenes from P. ginseng against ovarian cancer cell lines. Four unreported (1–4) and fifteen known (5–19) C17 polyacetylenes were obtained from the roots of P. ginseng using repeated chromatography (open column, MPLC, and preparative HPLC). The chemical structures of all the compounds were determined by analyzing their spectroscopic data (NMR, IR, and optical rotation) and HR-MS. The structures of new polyacetylenes were elucidated as (3S,8S,9R,10R)-(-)-heptadeca-9,10-epoxy-4,6-diyne-3,8-diyl diacetate (1), (3S,8S,9R,10R)-(−)-heptadeca-1-en-9,10-epoxy-4,6-diyne-3,8-diyl diacetate (2), (−)-haptadeca-9,10-epoxy-8-methoxy-4,6-diyne-3,11-diol (3), and (3R,9R,10R)-(+)-3-acetoxy-9,10-dihydroxyheptadeca-1-en-4,6-diyne (4), named ginsenoynes O, P, and Q, and 3-acetyl panaxytriol, respectively. Subsequently, in vitro experiments on A2780 and SKOV3 human epithelial ovarian carcinoma cells were performed to assess the cytotoxic properties of the isolates. Among the isolates, panaquinquecol 4 (15) exhibited the most remarkable cytotoxic effects on both human ovarian cancer cells A2780 (IC50 value of 7.60 μM) and SKOV3 (IC50 value of 27.53 μM). Therefore, C17 polyacetylenes derived from P. ginseng may warrant further investigation for their therapeutic potential in epithelial ovarian cancer. [ABSTRACT FROM AUTHOR]

Conducting polymers (CPs) are highly conjugated organic macromolecules, where the electrical charge is transported in intra- and inter-chain pathways. Polyacetylene, polythiophene and its derivatives, polypyrrole and its derivatives, and polyaniline are among the best-known examples. These compounds have been used as electrode modifiers to gain sensitivity and selectivity in a large variety of analytical applications. This review, after a brief introduction to the electrochemistry of CPs, summarizes the application of CPs' electrode interfaces towards heavy metals' detection using potentiometry, pulse anodic stripping voltammetry, and alternative non-classical electrochemical methods. [ABSTRACT FROM AUTHOR]

SUMMARY: Plants are able to construct lineage‐specific natural products from a wide array of their core metabolic pathways. Considerable progress has been made toward documenting and understanding, for example, phenylpropanoid natural products derived from phosphoenolpyruvate via the shikimate pathway, terpenoid compounds built using isopentyl pyrophosphate, and alkaloids generated by the extensive modification of amino acids. By comparison, natural products derived from fatty acids have received little attention, except for unusual fatty acids in seed oils and jasmonate‐like oxylipins. However, scattered but numerous reports show that plants are able to generate many structurally diverse compounds from fatty acids, including some with highly elaborate and unique structural features that have novel bioproduct functionalities. Furthermore, although recent work has shed light on multiple new fatty acid natural product biosynthesis pathways and products in diverse plant species, these discoveries have not been reviewed. The aims of this work, therefore, are to (i) review and systematize our current knowledge of the structures and biosynthesis of fatty acid‐derived natural products that are not seed oils or jasmonate‐type oxylipins, specifically, polyacetylenic, very‐long‐chain, and aromatic fatty acid‐derived natural products, and (ii) suggest priorities for future investigative steps that will bring our knowledge of fatty acid‐derived natural products closer to the levels of knowledge that we have attained for other phytochemical classes. Significance Statement: Plant chemicals play important roles in human health and renewable, petroleum‐like bioproducts, underscoring the importance of fundamental knowledge of these compounds. Substantial progress has been made toward understanding the structures and biosynthesis of plant chemicals such as terpenoids and alkaloids, but our knowledge of fatty acid‐derived chemicals, with the exception of seed oils and jasmonate‐type oxylipins, is not as well developed. This review summarizes our understanding of the structures and biosynthesis of polyacetylenic, very‐long‐chain, and aromatic fatty acid‐derived natural products and outlines areas for future investigation. [ABSTRACT FROM AUTHOR]

Using the non-equilibrium Green's function formalism in combination with density functional theory, we performed ab initio calculations of spin-dependent electron transport in molecular devices consisting of a polyacetylene (CnHn+1) chain vertically attached to a carbon chain sandwiched between two semi-infinite zigzag-edged graphene nanoribbon electrodes. Spin-charge transport in the device could be modulated to different magnetic configurations by an external magnetic field. The results showed that single spin conduction could be obtained. Specifically, the proposedCnHn+1 devices exhibited several interesting effects, including (dual) spin filtering, spin negative differential resistance, odd-even oscillation, and magnetoresistance (MR). Marked spin polarization with a filtering efficiency of up to 100% over a large bias range was found, and the highest MR ratio for the CnHn+1 junctions reached 4.6x104. In addition, the physical mechanisms for these phenomena were also revealed. [ABSTRACT FROM AUTHOR]

Herein, 17 previously undescribed polyacetylenes and 9 known ones were isolated from Tridax procumbens L. Their structures were identified using spectroscopic techniques (NMR, UV, IR, MS and optical rotation), the modified Mosher method, electronic circular dichroism (ECD) data and ECD calculation. The cytotoxicity of polyacetylenes on six human tumour cell lines (K562, K562/ADR, AGS, MGC-803, SPC-A-1 and MDA-MB-231) was evaluated. (3 S ,10 R)-tridaxin B (2a), (3 S ,10 S)-tridaxin B (2b) and tridaxin F (8) demonstrated substantial cytotoxic effects against the K562 cell line, with half-maximal inhibitory concentration (IC 50) values of 2.62, 14.43 and 17.91 μM, respectively. Cell and nucleus morphology assessments and Western blot analysis confirmed that the cytotoxicity of the three polyacetylenes on K562 cells was mediated through a dose-dependent apoptosis pathway. Furthermore, (3 S ,10 R)-tridaxin A (1a) and tridaxin G (9) exhibited considerable inhibitory effects on lipopolysaccharide-stimulated nitric oxide production in RAW 264.7 macrophages, with IC 50 values of 15.92 and 20.35 μM, respectively. Further investigations revealed that 9 exerted anti-inflammatory activities by impeding the nuclear translocation of NF- κ B and down-regulating the expression of pro-inflammatory factors, including those of iNOS, COX-2, IL-1 β and IL-6, in a concentration-dependent manner. The study provides evidence that polyacetylenes from T. procumbens may serve as a potential source of anti-tumour or anti-inflammatory agents for treating related diseases. Twenty-six polyacetylenes, including seventeen previously undescribed compounds, were isolated from Tridax procumbens L. [Display omitted] • Seventeen previously undescribed polyacetylenes were isolated from Tridax procumbens. • Cytotoxic and anti-inflammatory activities of these polyacetylenes were investigated. • Polyacetylenes from T. procumbens may serve as anti-tumor or anti-inflammatory agent. [ABSTRACT FROM AUTHOR]

The measurement of anisotropic residual dipolar couplings (RDCs) parameters for the structure elucidation of organic molecules relies on suitable alignment media. Employment of self‐assembled liquid crystalline systems to create anisotropic alignment can be an effective way to realize aligned samples and acquire RDCs. This Mini‐review highlights the recent advances on amino acid‐based helical polymers and supramolecular oligomers forming rigid, rod‐like structures that aggregate into ordered liquid crystalline phases, including amino acid‐based helical polyisocyanides, polyacetylenes, polypeptides, and oligopeptides assembled alignment media. The methodology for the determination of anisotropic liquid crystals is briefly discussed, and a summary of recent research progress in the enantiodifferentiation of helical polymers aligned media is followed. In addition, the self‐assembled mechanism of oligopeptides and their RDCs structural analysis are also described. [ABSTRACT FROM AUTHOR]

Four new polyacetylene substances, sadivaethynes A–D, were isolated from the ethanol extract of the roots of Saposhnikovia divaricata (Turcz.) Schischk using repeated column chromatography. Structural elucidation of compounds 1–4 was established by 1D and 2D NMR spectra referring to the literature, together with high-resolution mass spectrometric analysis. All compounds were evaluated for cytotoxicity against two human cancer cell lines (MGC-803, Ishikawa) in vitro. [ABSTRACT FROM AUTHOR]

Angelica dahurica (A. dahurica) root is a famous edible medicinal herb that has been used in China for thousands of years. To date, more than 300 chemical constituents have been discovered from A. dahurica. Among these ingredients, coumarins and volatile oils are the major active compounds. Moreover, a few other compounds have also been isolated from the root of A. dahurica, such as alkaloids, phenols, sterols, benzofurans, polyacetylenes and polysaccharides. Modern pharmacological studies demonstrated that the root of A. dahurica and its active components displayed various bioactivities such as anti-inflammation, anti-tumor, anti-oxidation, analgesic activity, antiviral and anti-microbial effects, effects on the cardiovascular system, neuroprotective function, hepatoprotective activity, effects on skin diseases and so on. Based on these studies, this review focused on the research publications of A. dahurica and aimed to summarize the advances in the traditional uses, phytochemistry and pharmacology which will provide reference for the further studies and applications of A. dahurica. [ABSTRACT FROM AUTHOR]

Polymer‐based circularly polarized luminescent (CPL) materials have attracted ever‐increasing interest. However, to construct CPL materials from achiral monomers is still a big challenge. Here, a series of chiral helical substituted polyacetylenes are prepared by helix‐sense‐selective polymerization (HSSP) of achiral acetylenic monomers (achiral monomer + fluorescent monomer). HSSPs are accomplished in a bi‐solvent mixture consisting of chloroform and chiral α‐pinene (chiral component). Chirality transfers from the chiral component to the helical copolymers during polymerization, thereby endowing the copolymers with helical chirality. The resulting copolymers are then fabricated into blend films which exhibit intense optical activity and CPL. The monomer ratio and the physical state of the copolymers have significant impacts on their chiroptical and CPL properties. The maximum luminescence dissymmetry factor of the blend films can be up to 1.3 × 10−2. The universality of the established strategy for exploring polymer‐based CPL materials is demonstrated by using different achiral fluorescent monomers. The present work opens a novel alternative for developing CPL‐active polymeric materials starting from achiral monomers. [ABSTRACT FROM AUTHOR]

Thirteen root extract samples of four goldenrod (Solidago) species present in Europe were investigated by hyphenated high-performance thin-layer chromatography (HPTLC). Only S. virgaurea is native, whereas S. gigantea, S. canadensis, and S. graminifolia have been introduced from North America. The bioactive zones in the Aliivibrio fischeri bioautogram were identified as polyacetylenes, labdane diterpenes, or clerodane diterpenes by HPTLC coupled to high-resolution mass spectrometry, exploiting the two interfaces, heated electrospray ionization, and direct analysis in real time. Principal component analysis of the obtained bioprofiles enabled the discrimination of the Solidago species. Furthermore, chemometrics pointed to the discriminative components, the main bioactive markers of the species: Z,Z-matricaria ester from S. virgaurea, solidagenone from S. canadensis, solidagoic acid A, and a dialdehyde clerodane diterpene from S. gigantea, and Z-dehydromatricaria ester from S. graminifolia. [ABSTRACT FROM AUTHOR]

The plant species Pimpinella serbica (Vis.) Drude, endemic to West Balkans, belongs to the genus Pimpinella L. (Apiaceae) according to newer botanical classification. Initially, the plant was described as Pancicia serbica Vis. and long considered as a monotypic genus. Previous phytochemical investigations of this plant were limited to the essential oil analysis by the GC–MS method. This is first study that includes LC-DAD–MS screening of the extracts of the roots and aerial parts, followed by isolation of secondary metabolites using chromatographic techniques. Five compounds belonging to phenylpropanoids and polyacetylenes, well known for their bioactivities, were isolated and structurally determined by combined spectroscopic methods (UV, NMR, MS). Dillapiole (1), nothoapiole (2) and oplopantriol A 18-acetate (4) were found in both extracts, while falcarindiol (3) was isolated from the roots and dendrotrifidol (5) from the aerial parts only. The phytochemical profile of P. serbica L. supports its position in the Pimpinella L. genus.

Severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) main protease (S-CoV-2 Mpro) is one of the main targets in designing antiviral against SARS-CoV-2. Centella asiatica contains several triterpenoids, polyacetylenes, and benzoic ester derivative with various biological activities including anti-inflammation and antiviral. Triterpenoids from C. asiatica could act as inhibitors of S-CoV-2 Mpro. The main objective of this study was to identify potential natural products from C. asiatica as S-CoV-2 Mpro inhibitor with better pharmacokinetic through in silico molecular docking method. : As much as 11 compounds from C. asiatica were docked with S-CoV-2 Mpro (PDB ID: 6LU7) using AutoDock v4.2.6. Pharmacokinetic parameters of these compounds were assessed using SwissADME (free access webserver). Molecular docking results of 11 natural products indicated that asiatate 6 and asiatate 10 have strong interaction with quite similar binding free energy compared to native ligand (‒9.00 and‒9.58 kcal/mol compared to ‒9.18 kcal/mol, respectively) with proper interaction to the catalytic dyad (His41 and Cys145). Pharmacokinetic analysis revealed that asiatate 4, asiatate 10, and asiatate 11 have poor pharmacokinetic properties. These results indicated that asiatate 6 could be recommended for further study as S-CoV-2 Mpro inhibitor.

Three new polyacetylenes (1–3), together with six known polyacetylenes (4–9), were isolated from a 95% aqueous ethanol extract of the Atractylodes japonica Koidz.ez Kitam. Their structures were elucidated by HR-ESI -MS and NMR techniques as well as comparison with those reported in literatures. The cytotoxic activity of 1–3 were also evaluated. [ABSTRACT FROM AUTHOR]

Aim: The subterranean tissues of Panax ginseng, especially the root, have long been used in traditional Asian medicine. In traditional medicine, various formulas contain ginseng to relieve fatigue, improve splenic function, and strengthen immunity, while recent studies have reported many additional benefits, including improvement of Alzheimer's dementia. Multiple ginsenosides, polyacetylenes, and polysaccharides in ginseng root and rhizome contribute to these therapeutic activities. Most ginseng used today is cultivated and takes a long time to mature, so changes in the bioactive constituent profile with age could alter the potential health benefits. However, most studies on such age‐dependent changes in chemical composition have focused on ginsenosides. To examine the full spectrum of age‐dependent changes, the current study analyzed the contents of multiple secondary metabolites and primary metabolites in samples cultivated from one to five years. Methods: The contents of multiple secondary metabolites such as polyacetylenes and primary metabolites such as fatty acids, sugars, and phospholipids as well as ginsenosides were determined by liquid or gas chromatography–mass spectroscopy (LC/MS or GC/MS). Results: Ginsenoside Ro and 1,2‐dilinoleoyl‐sn‐glycero‐3‐phosphocholine increased substantially and progressively with number of years of cultivation. Other ginsenosides and sugars also increased with age, but with greater variability. Conversely, concentrations of falcarinol, fatty acids, and phosphatidic acid decreased with cultivation time. Conclusion: Cultivation years may influence the specific medicinal properties and other health benefits of ginseng preparations. [ABSTRACT FROM AUTHOR]

In the planting of crops, especially medicinal plants, formula fertilization is important for improving the utilization rate of elements, soil quality, crop yield, and quality. Therefore, it is important to study targeted fertilizer application schemes for sustainable agricultural development and environmental protection. In this study, an L9(34) orthogonal design was used to conduct a field experiment to study the effects of NPK combined application on the growth and pharmacodynamic component biosynthesis of Atractylodes chinensis (DC.) Koidz. Results showed that after applying a base fertilizer at the seedling stage (late May), topdressing at the vegetative stage (late June) and fruit stage (late August) was beneficial to the growth and development of A. chinensis. The high concentrations of phosphorus were conducive to the accumulation of yield and effective components, and the best harvest time was after late October. Principal component analysis (PCA) showed that the comprehensive score of T6 treatment was the highest, indicating that the optimal fertilization scheme for the high yield and high quality of A. chinensis was (N2P3K1): N 180, P2O5 225, and K2O 105 kg⋅ha–1. A signaling response analysis showed that during the growth and development of A. chinensis , the T6 fertilization scheme had clear effects on the activity and gene expression of the key enzymes acetyl-CoA carboxylase (ACC) and farnesyl pyrophosphate synthase (FPPS). Under the T4 [(N2P1K2): N 180, P2O5 75, and K2O 210 kg⋅ha–1] fertilization scheme, the activity and gene expression of the key enzyme 3-hydroxy-3-methylglutaryl-CoA reductase (HMGR) were higher. Moreover, ACC was closely related to the synthesis of the polyacetylene component atractylodin, and FPPS played an important regulatory role in the synthesis of sesquiterpene components atractylenolide II, β-eudesmol, and atractylon. In summary, the high phosphorus fertilization scheme T6 could notably increase the yield of A. chinensis , and promote the accumulation of polyacetylene and sesquiterpene volatile oils by increasing the expression of ACC and FPPS. Therefore, we postulate that the precise application of nutrients (NPK) plays a vital role in the yield formation and quality regulation of A. chinensis. [ABSTRACT FROM AUTHOR]

Background: Falcarinol-type polyacetylenes (PAs) such as falcarinol (FaOH) and falcarindiol (FaDOH) are produced by several Apiaceae vegetables such as carrot, parsnip, celeriac and parsley. They are known for numerous biological functions and contribute to the undesirable bitter off-taste of carrots and their products. Despite their interesting biological functions, the genetic basis of their structural diversity and function is widely unknown. A better understanding of the genetics of the PA levels present in carrot roots might support breeding of carrot cultivars with tailored PA levels for food production or nutraceuticals. Results: A large carrot F2 progeny derived from a cross of a cultivated inbred line with an inbred line derived from a Daucus carota ssp. commutatus accession rich in PAs was used for linkage mapping and quantitative trait locus (QTL) analysis. Ten QTLs for FaOH and FaDOH levels in roots were identified in the carrot genome. Major QTLs for FaOH and FaDOH with high LOD values of up to 40 were identified on chromosomes 4 and 9. To discover putative candidate genes from the plant fatty acid metabolism, we examined an extended version of the inventory of the carrot FATTY ACID DESATURASE2 (FAD2) gene family. Additionally, we used the carrot genome sequence for a first inventory of ECERIFERUM1 (CER1) genes possibly involved in PA biosynthesis. We identified genomic regions on different carrot chromosomes around the found QTLs that contain several FAD2 and CER1 genes within their 2-LOD confidence intervals. With regard to the major QTLs on chromosome 9 three putative CER1 decarbonylase gene models are proposed as candidate genes. Conclusion: The present study increases the current knowledge on the genetics of PA accumulation in carrot roots. Our finding that carrot candidate genes from the fatty acid metabolism are significantly associated with major QTLs for both major PAs, will facilitate future functional gene studies and a further dissection of the genetic factors controlling PA accumulation. Characterization of such candidate genes will have a positive impact on carrot breeding programs aimed at both lowering or increasing PA concentrations in carrot roots. [ABSTRACT FROM AUTHOR]

Infectious disease-causing pathogenic microorganisms grow rapidly within quorum sensing mediated biofilms. Attempts are made to restrict quorum sensing in pathogens, and the formation of biofilms has paved the way for the identification of bioactive phytochemicals. Anti-QS compounds have been proven to reduce bacterial pathogenicity in the past. Medicinal plants provide an enticing repertoire of phytochemicals with distinct microbial disease-controlling potential due to the vast spectrum of secondary metabolites included in extracts such as phenolics, quinones, flavonoids, alkaloids, terpenoids, and polyacetylenes. This review makes a specialty of the bioactive molecules produced using vegetation which have a target closer to quorum sensing accompanied via biofilm formation in pathogenic microbes. [ABSTRACT FROM AUTHOR]

Two novel poly(biphenylylacetylene)s (PBPAs) bearing achiral alkylphenyl groups at the 4′‐position of the biphenyl pendant through ester linkers with different sequences were synthesized by the rhodium‐catalyzed polymerization of the corresponding monomers. The influence of the alkylphenyl pendants and the ester sequences on the macromolecular helicity induction and subsequent static helicity memory was investigated. In addition, the chiral recognition ability as chiral stationary phases for high‐performance liquid chromatography of the helicity‐memorized PBPAs was also examined. Both polymers formed almost perfect right‐ and left‐handed helical conformations through noncovalent chiral interactions with enantiomeric alcohols, and their induced macromolecular helicities were completely retained ("memorized") after removal of the helix inducer. A PBPA bearing a 4‐n‐butylphenoxycarbonyl pendant group with a static helicity memory showed a remarkably high chiral recognition ability toward a wide variety of chiral aromatics, including simple point chiral compounds, axially chiral biaryls, a chiral spiro compound, helicenes, and planar chiral cyclophanes, particularly under the reversed‐phase conditions. [ABSTRACT FROM AUTHOR]