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The alkamide content and specific tissue localization in the cypselae of Heliopsis longipes were investigated using gas chromatography–electron ionization mass spectrometry (GC-EIMS) and multiphoton fluorescence microscopy (MPFM). GC-EIMS analysis identified two olefinic alkamides: affinin (spilanthol) and N-2-methylbutyl-2E,6Z,8E-decatrienamide. Microscopic analysis revealed that alkamides are localized within the cotyledons, and specifically compartmentalized in lipid bodies, highlighting their spatial organization. The linear unmixing of fluorescence emission fingerprints showed that affinin exhibits autofluorescence at 693 nm, corresponding to the red spectral region. This emission is attributed to the conjugated double bonds in its acyl chain. This study is the first to report on the presence and precise localization of alkamides in the cypselae of H. longipes. [ABSTRACT FROM AUTHOR]

Zanthoxylum species have long been utilized in traditional medicine; among their various properties, they provide an analgesic effect. Central to this medicinal application are alkamides, a class of alkaloids characterized by their unsaturated fatty acid chains. These compounds are particularly noted for their distinctive alleviation of tingling and numbing effects, which are beneficial in dental pain management and local anesthesia. This review synthesizes the existing phytochemical research on alkamides derived from 11 Z. species, focusing on their chemical properties, pharmacodynamics and clinical implications. The analysis includes an examination of the structure–activity relationships (SARs), pharmacokinetics and mechanisms by which these compounds modulate sensations such as pungency and numbness, contributing to their analgesic and local anesthetic efficacy. This systemic review identifies significant research gaps, including the need for comprehensive evaluations of alkamide efficacy, detailed explorations of their pharmacological mechanisms and expanded clinical applications. These areas represent key opportunities for future investigations to enhance the understanding and utilization of alkamides in medical treatments. [ABSTRACT FROM AUTHOR]

Background: Echinacea species, particularly Echinacea purpurea, Echinacea angustifolia, and Echinacea pallida, are renowned for their immunomodulatory, antibacterial, and antiviral properties. Objectives: This review explores the mechanisms by which echinacea herbal extracts modulate immune responses, focusing on their effects on both innate and adaptive immunity in bacterial and viral infections. Results: Key bioactive compounds, such as alkamides, caffeic acid derivatives, flavonoids, and polysaccharides, contribute to these effects. These compounds enhance immune cell activity, including macrophages and natural killer cells, stimulating cytokine production and phagocytosis. The antibacterial activity of echinacea against respiratory pathogens (Streptococcus pneumoniae, Haemophilus influenzae, Legionella pneumophila) and skin pathogens (Staphylococcus aureus, Propionibacterium acnes) is reviewed, as well as its antiviral efficacy against viruses like herpes simplex, influenza, and rhinovirus. Echinacea's potential as a complementary treatment alongside conventional antibiotics and antivirals is discussed, particularly in the context of antibiotic resistance and emerging viral threats. Conclusions: Challenges associated with variability in phytochemical content and the need for standardized extraction processes are also addressed. This review provides a comprehensive overview of echinacea's therapeutic potential and outlines future directions for research, including clinical trials and dosage optimization. [ABSTRACT FROM AUTHOR]

Purple coneflower (Echinacea purpurea Moench [L.]) is widely used as a health supplement and is cultivated for its production of bioactive phytochemicals. However, there is a lack of information on how agronomic planting designs and environment affect the phytochemical content of different coneflower tissues. Experimental plots were established at two locations in Minnesota to evaluate the effect of environment and agronomic planting design on the phytochemical profile of purple coneflower, as well as the relative content of several provisionally identified compounds. Root, stem, leaf, flower, and seed tissues were harvested, and extracts were analysed using liquid chromatography-mass spectrometry. The growing environment affected the levels of several caffeic acid derivatives in leaf, stem, and root tissue, but agronomic design had little to no effect on phytochemical content. Although all tissue types contained phytochemicals of medicinal interest, no single tissue contained the highest amount of all compounds with known bioactive properties, indicating that the most beneficial purple coneflower supplements may be the combination of several tissue types. Additionally, the phytochemical content of purple coneflower seed, which is uncommon in Echinacea supplements, was chemically similar to root tissue. Seed tissue, after additional evaluations, may be a suitable alternative for root in supplement mixtures. [ABSTRACT FROM AUTHOR]

Background: Echinacea species, particularly Echinacea purpurea, Echinacea angustifolia, and Echinacea pallida, are renowned for their immunomodulatory, antibacterial, and antiviral properties. Objectives: This review explores the mechanisms by which echinacea herbal extracts modulate immune responses, focusing on their effects on both innate and adaptive immunity in bacterial and viral infections. Results: Key bioactive compounds, such as alkamides, caffeic acid derivatives, flavonoids, and polysaccharides, contribute to these effects. These compounds enhance immune cell activity, including macrophages and natural killer cells, stimulating cytokine production and phagocytosis. The antibacterial activity of echinacea against respiratory pathogens (Streptococcus pneumoniae, Haemophilus influenzae, Legionella pneumophila) and skin pathogens (Staphylococcus aureus, Propionibacterium acnes) is reviewed, as well as its antiviral efficacy against viruses like herpes simplex, influenza, and rhinovirus. Echinacea’s potential as a complementary treatment alongside conventional antibiotics and antivirals is discussed, particularly in the context of antibiotic resistance and emerging viral threats. Conclusions: Challenges associated with variability in phytochemical content and the need for standardized extraction processes are also addressed. This review provides a comprehensive overview of echinacea’s therapeutic potential and outlines future directions for research, including clinical trials and dosage optimization.

Alkylamides are secondary metabolites in Acmella oleracea and display wide applications in treating several diseases. Since alkylamides can inhibit pain, this work aims to evaluate the antinociceptive profile of A. Oleracea methanolic extracts used in vivo and in silico assays. The extracts inhibited the neurogenic and inflammatory phases of the formalin test, ratifying the antinociceptive effect of alkylamides. Furthermore, the results from molecular docking demonstrated the interaction of A. oleracea alkylamides with the CB1/CB2 and TRPV1 receptors. Additionally, the crude methanolic extract of flowers did not induce potential side effects related to the classical cannabinoid tetrad: hypolocomotion and catalepsy. In conclusion, this work confirms the potential of the alkylamides of A. Oleracea as antinociceptive agents and, for the first time, correlates its effects with the endocannabinoid and vanilloid systems through in silico assays. [ABSTRACT FROM AUTHOR]

Nanobiotechnology is a popular branch of science that is gaining interest among scientists and researchers as it allows for the green manufacturing of nanoparticles by employing plants as reducing agents. This method is safe, cheap, reproducible, and eco-friendly. In this study, the therapeutic property of Piper nigrum fruit was mixed with the antibacterial activity of metallic copper to produce copper nanoparticles. The synthesis of copper nanoparticles was indicated by a color change from brown to blue. Physical characterization of Piper nigrum copper nanoparticles (PN-CuNPs) was performed using UV-vis spectroscopy, FT-IR, SEM, EDX, XRD, and Zeta analyzer. PN-CuNPs exhibited potential antioxidant, antibacterial, and cytotoxic activities. PN-CuNPs have shown concentration-dependent, enhanced free radical scavenging activity, reaching maximum values of 92%, 90%, and 86% with DPPH, H2O2, and PMA tests, respectively. The antibacterial zone of inhibition of PN-CuNPs was the highest against Staphylococcus aureus (23 mm) and the lowest against Escherichia coli (10 mm). PN-CuNPs showed 80% in vitro cytotoxicity against MCF-7 breast cancer cell lines. Furthermore, more than 50 components of Piper nigrum extract were selected and subjected to in silico molecular docking using the C-Docker protocol in the binding pockets of glutathione reductase, E. coli DNA gyrase topoisomerase II, and epidermal growth factor receptor (EGFR) tyrosine to discover their druggability. Pipercyclobutanamide A (26), pipernigramide F (32), and pipernigramide G (33) scored the highest Gibbs free energy at 50.489, 51.9306, and 58.615 kcal/mol, respectively. The ADMET/TOPKAT analysis confirmed the favorable pharmacokinetics, pharmacodynamics, and toxicity profiles of the three promising compounds. The present in silico analysis helps us to understand the possible mechanisms behind the antioxidant, antibacterial, and cytotoxic activities of CuNPs and recommends them as implicit inhibitors of selected proteins.

A new nor-ent-kaurene diterpene and ten other compounds were isolated from Annona vepretorum stems, including four kaurene diterpenes, three alkamides, one sesquiterpene and two steroids. Their chemical structures were elucidated using spectroscopic methods, including 1D-, 2D-NMR, and HRESIMS. The absolute configuration of compounds 1, 5, 8, 9 and 10 was confirmed by CD experiments. Compounds 1–5 and 8–10 were evaluated for cytotoxic activity using (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) MTT method, against three human carcinoma cell lines: human colon (HCT-116), glioblastoma (SF295) and prostate (PC3). However, all isolated compounds exhibited low cytotoxic activity. [ABSTRACT FROM AUTHOR]

Chemotherapy‐induced neuropathy represents the main dose‐limiting toxicity of several anticancer drugs, such as oxaliplatin, leading to chronic pain and an impairment of the quality of life. Echinacea purpurea n‐hexane extract (EP4–RE; rich in alkamides) and butanolic extract (EP4–RBU; rich in polyphenols) have been characterized and tested in an in vivo model of oxaliplatin‐induced neuropathic pain, addressing the endocannabinoid system with alkamides and counteracting the redox imbalance with polyphenols. Thermal hypersensitivity was evaluated by the Cold Plate test. EP4–RE showed a dose‐dependent anti‐hyperalgesic profile. The extract was more effective than its main constituent, dodeca‐2 E,4 E,8Z,10 E/Z‐tetraenoic acid isobutylamide (18 mg kg−1, twofold to equimolar EP4–RE 30 mg kg−1), suggesting a synergy with other extract constituents. Administration of cannabinoid type 2 (CB2) receptor‐selective antagonist completely blocked the anti‐allodynic effect of EP4–RE, differently from the antagonism of CB1 receptors. EP4–RBU (30 mg kg−1) exhibited anti‐neuropathic properties too. The effect was mainly exerted by chicoric acid, which administered alone (123 μg kg−1, equimolar to EP4–RBU 30 mg kg−1) completely reverted oxaliplatin‐induced allodynia. A synergy between different polyphenols in the extract had not been highlighted. Echinacea extracts have therapeutic potential in the treatment of neuropathic pain, through both alkamides CB2‐selective activity and polyphenols protective properties. [ABSTRACT FROM AUTHOR]

Acmella oleracea (L.) R. K. Jansen, commonly referred to as "Jambu", is a valuable medicinal plant native to the Amazon regions. Inflorescences of A. oleracea is utilized as local anesthetic properties and for its insecticidal, antiparasitic, and anthelmintic attributes. This study aimed to evaluate the in vitro and in vivo antiparasitic properties of A. oleracea extract and spilanthol (SPL) against Schistosoma mansoni. The ethanolic extract of A. oleracea inflorescences (AoE) was prepared, analyzed by HPLC-DAD, and characterized by UHPLC-HRMS/MS. SPL was isolated from AoE by chromatographic fractionation. The antischistosomal properties of AoE and SPL were evaluated in vitro against adult schistosomes and in preclinical assays using murine models of patent S. mansoni infection. Through UHPLC-HRMS/MS analysis, 14 alkamides were annotated in AoE. HPLC-DAD analysis of AoE revealed a peak with a substantial relative area of ∼85%, which was isolated and identified as SPL. AoE and SPL caused mortality of adult schistosomes ex vivo , showing EC 50 values of 32.6 μg/mL and 27.8 μM, respectively, without affected Vero cells or Caenorhabditis elegans. In preclinical studies, the oral administration (400 mg/kg) of AoE and SPL resulted in significant reductions in worm burden of 28% and ∼42%, respectively. Additionally, SPL exhibits remarkable effects on oogram, decreasing egg burden and the number of immature eggs by over 80%, while also promoting significant reductions in hepato- and splenomegaly. The research underscores the antischistosomal activity of A. oleracea highlighting the potential of SPL as a lead for the development of new schistosomicidal drugs and encouraging further studies to validate the traditional anthelmintic use of A. oleracea inflorescences. [Display omitted] • A. oleracea extract exhibited in vitro antischistosomal effects. • A number of alkamides were annotated in A. oleracea extract by UHPLC-HRMS/MS. • Spilanthol was isolated and displayed in vitro and in vivo antischistosomal effects. • Spilanthol and A. oleracea extract were active against S. mansoni in mice. • This study encourages further research to substantiate the traditional anthelmintic use of A. oleracea inflorescences. [ABSTRACT FROM AUTHOR]

The ability of dermatophytes to develop biofilms is possibly involved in therapeutic failure because biofilms impair drug effectiveness in the infected tissues. Research to find new drugs with antibiofilm activity against dermatophytes is crucial. In this way, riparins, a class of alkaloids that contain an amide group, are promising antifungal compounds. In this study, we evaluated the antifungal and antibiofilm activity of riparin III (RIP3) against Trichophyton rubrum, Microsporum canis, and Nannizzia gypsea strains. We used ciclopirox (CPX) as a positive control. The effects of RIP3 on fungal growth were evaluated by the microdilution technique. The quantification of the biofilm biomass in vitro was assessed by crystal violet, and the biofilm viability was assessed by quantifying the CFU number. The ex vivo model was performed on human nail fragments, which were evaluated by visualization under light microscopy and by quantifying the CFU number (viability). Finally, we evaluated whether RIP3 inhibits sulfite production in T. rubrum. RIP3 inhibited the growth of T. rubrum and M. canis from 128 mg/L and N. gypsea from 256 mg/L. The results showed that RIP3 is a fungicide. Regarding antibiofilm activity, RIP3 inhibited biofilm formation and viability in vitro and ex vivo. Moreover, RIP3 inhibited the secretion of sulfite significantly and was more potent than CPX. In conclusion, the results indicate that RIP3 is a promising antifungal agent against biofilms of dermatophytes and might inhibit sulfite secretion, one relevant virulence factor. [ABSTRACT FROM AUTHOR]

The cultivation of Echinacea purpurea for commerce and obtaining high-quality plant material on a large scale remain a challenge for growers. Another challenge for the following decades is to create sustainable agriculture that meets society's needs, has no environmental impact, and reduces the use of fertilizers and pesticides. The aims of this overview were: (1) to present the importance of the chemical compounds reported in E. purpurea; (1) to synthesize results about cultivation of the E. purpurea with arbuscular mycorrhizal fungi (AMF) and associated microorganisms; (2) to exemplify similar research with plants from the Asteraceae family, due to the limited number of published Echinacea studies; (3) to collect recent findings about how the inoculation with AMF affects gene expressions in the host plants; (4) to propose perspective research directions in the cultivation of E. purpurea, in order to increase biomass and economic importance of secondary metabolite production in plants. The AMF inocula used in the Echinacea experiments was mainly Rhizophagus irregularis. The studies found in the selected period (2012–2022), reported the effects of 21 AMFs used as single inocula or as a mixture on growth and secondary metabolites of 17 plant taxa from the Asteraceae family. Secondary metabolite production and growth of the economic plants were affected by mutualistic, symbiotic or parasitic microorganisms via upregulation of the genes involved in hormonal synthesis, glandular hair formation, and in the mevalonate (MVA), methyl erythritol phosphate (MEP) and phenylpropanoid pathways. However, these studies have mostly been carried out under controlled conditions, in greenhouses or in vitro in sterile environments. Since the effect of AMF depends on the variety of field conditions, more research on the application of different AMF (single and in various combinations with bacteria) to plants growing in the field would be necessary. For the identification of the most effective synergistic combinations of AMF and related bacterial populations, transcriptomic and metabolomic investigations might also be useful. [ABSTRACT FROM AUTHOR]

The bungeanools are a family of alkamide natural products isolated from the pericarps of Zanthoxylum bungeanum (Sichuan pepper), and they are structurally related to the sanshools. While the sanshools, especially hydroxy-α-sanshool, have been studied in a variety of contexts, research regarding the bungeanools has been much more limited. To facilitate their study, we have developed stereoselective syntheses of all four members of this family of compounds by using flexible routes that are also amenable to the synthesis of analogues. The key transformation in the syntheses was the stereoselective triphenylphosphine/phenol-catalyzed isomerization of an alkynoate to the corresponding conjugated E , E -dienoate. [ABSTRACT FROM AUTHOR]

N-acyl-L-homoserine lactones (AHLs) are involved in cell-to-cell communication in Gram-negative bacteria through a process termed quorum-sensing (QS). In this report, we evaluated the response of Arabidopsis thaliana primary roots to abscisic acid (ABA) in wild-type (WT) and decanamide resistant root 1 (drr1) mutant, previously reported to be resistant to N-decanoyl-L-homoserine lactone (C10-HL). When compared to WT seedlings, drr1 mutants were hypersensitive to ABA and had primary roots shorter, which correlated with lower cell division in meristems, a higher concentration of endogenous ABA, and a greater expression of ABI5 gene; and this shortened primary root phenotype was reversed in drr1abi5 double mutants. An analysis of expression of ABSCISIC ACID INSENSITIVE 4 (ABI4) showed an ABA-inducible pattern in primary root tips, which was further increased in drr1 mutant seedlings. Comparison of seed germination in WT, drr1, abi5, and drr1abi5 lines showed higher germination percentages in the following order under control condition: abi5 > drr1abi5 > WT > drr1, while abi5 and drr1abi5 germinated faster and drr1 germinated slower with respect to WT under ABA condition. Taken together, our results suggest that DRR1 is a negative regulator of ABA signaling probably acting upstream of the transcription factors ABI4 and ABI5, which influence ABA responsiveness in primary roots and seed germination. [ABSTRACT FROM AUTHOR]

The cultivation of Echinacea purpurea for commerce and obtaining high-quality plant material on a large scale remain a challenge for growers. Another challenge for the following decades is to create sustainable agriculture that meets society’s needs, has no environmental impact, and reduces the use of fertilizers and pesticides. The aims of this overview were: (1) to present the importance of the chemical compounds reported in E. purpurea; (1) to synthesize results about cultivation of the E. purpurea with arbuscular mycorrhizal fungi (AMF) and associated microorganisms; (2) to exemplify similar research with plants from the Asteraceae family, due to the limited number of published Echinacea studies; (3) to collect recent findings about how the inoculation with AMF affects gene expressions in the host plants; (4) to propose perspective research directions in the cultivation of E. purpurea, in order to increase biomass and economic importance of secondary metabolite production in plants. The AMF inocula used in the Echinacea experiments was mainly Rhizophagus irregularis. The studies found in the selected period (2012–2022), reported the effects of 21 AMFs used as single inocula or as a mixture on growth and secondary metabolites of 17 plant taxa from the Asteraceae family. Secondary metabolite production and growth of the economic plants were affected by mutualistic, symbiotic or parasitic microorganisms via upregulation of the genes involved in hormonal synthesis, glandular hair formation, and in the mevalonate (MVA), methyl erythritol phosphate (MEP) and phenylpropanoid pathways. However, these studies have mostly been carried out under controlled conditions, in greenhouses or in vitro in sterile environments. Since the effect of AMF depends on the variety of field conditions, more research on the application of different AMF (single and in various combinations with bacteria) to plants growing in the field would be necessary. For the identification of the most effective synergistic combinations of AMF and related bacterial populations, transcriptomic and metabolomic investigations might also be useful.

Introduction. The alcohol extract of Pellitory (Anacyclus pyrethrum) roots has been previously shown to exert anticancer activities on the Human Colorectal Cancer Cell Line (HCT) by targeting apoptosis, metastasis and cell cycle arrest. However, the nature of the cytotoxic molecules associated with this activity remains unexplored.

The present work aimed to determine the safety parameters of two new alkamides, affinin and hexahydroaffinin, with antinociceptive activity. To predict the preliminary acute toxicity, we used the acute and subchronic toxicity (50 mg/kg, orally [po]) in Swiss Webster mice. Genotoxicity assayed via analysis of cell micronuclei of the femoral bone marrow in mice; at the same time, metabolic parameters determined from peripheral blood samples. Furthermore, to discard the neuropharmacological effects, we assessed the ambulatory activity in mice to determine the possible effects in the central nervous system. Finally, we used capsaicin as a positive control of alkamides. According to our results, hexahydroaffinin (LD50 ≥ 5,000 mg/kg, po) is significantly less noxious than affinin (LD50 = 1,442.2 mg/kg, po) or capsaicin (LD50 = 489.9 mg/kg, po). In subchronic administration, we did not observe any changes in hematological or biochemical parameters in any compound analyzed from peripheral blood samples. Finally, the data from the genotoxicity assay showed micronuclei formation in 28%, 5%, and 3% of mice in the capsaicin, affinin, and hexahydroaffinin groups, respectively. With the results obtained in the present investigation, we suggest that affinin and hexahydroaffinin are not only useful candidates for possible new drugs but also safe compounds. [ABSTRACT FROM AUTHOR]

Echinacea species are reported for a large content of bioactive compounds, but their effects on phytoparasitic nematodes are still unknown. This study comparatively investigated the in vitro activity of chemically characterized extracts from E. angustifolia, E. pallida and E. purpurea on juveniles and eggs of the root-knot nematode Meloidogyne incognita. Suppressiveness of soil amendments with Echinacea plant biomasses was also investigated against M. incognita on tomato in potting mixes. More than 50% juvenile mortality occurred after a 48-h exposure to a 500 µg mL−1 solution of all Echinacea extracts, as well as more than 50% of M. incognita eggs did not hatch after a 1-week exposure to the same concentration of E. angustifolia extracts. Nematode multiplication on tomato roots was always significantly reduced in soil amended with all Echinacea biomasses, as well as almost all treatments also resulted in a significant tomato growth increase. Polar compounds such as echinacoside and chicoric acid were the main components of the extracts from Echinacea aerial parts, whereas apolar components as alkamides prevailed in root extracts. Data confirmed the potential of the three Echinacea species, mainly E. angustifolia, for the formulation of new formulates for a sustainable nematode management. [ABSTRACT FROM AUTHOR]

• Five new compounds of T. inamoena were isolated. • Were isolated one phytosteroid and four amides derived from hydroxycinnamic acid. • Fractions derived from the plant extract showed antibacterial activity;. • The products from this species reduced the MIC of conventional antibiotics. Tacinga inamoena is a cactus na''tive to the Northeast region of Brazil, used in popular medicine to treat disorders of the urethra as well as asthma and inflammation. Of the roots from T. inamoena , five previously unreleased compounds in the genus, β-sitosterol-3- O - d -glucopyranoside, N -trans-feruloyl-4- O -methyldopamine, N -cis-feruloyl-4- O -methyldopamine, N-trans-feruloyl tyramine and N -cis-feruloyl tyramine were isolated and their structures were elucidated by spectroscopic analysis (IR, MS and NMR). The antimicrobial activities of the partitioned phases were evaluated against bacterial and fungal strains, with promising results, especially of the ethyl acetate phase against Staphylococcus aureus ATCC 25,923. Furthermore, in the modulation tests between the phases and β-sitosterol-3- O - d -glucopyranoside with aminoglycosides, cephalosporins and quinolones, against the strains of E. coli 5A and Pseudomonas aeruginosa , there was a substantial increase of the activity of these antibiotics, with a significant decrease of MICs. The products from T. inamoena showed low toxicity in human erythrocytes. The present study presented relevant compounds and important antibacterial activities and suggests that the glycosylated β-sitosterol can be used to modulate the activity of antibiotics. [ABSTRACT FROM AUTHOR]

In the present study, ethanolic extract from Heliopsis longipes roots and affinin/spilanthol against Aspergillus parasiticus growth and aflatoxins production were studied in relation to the expression of aflD and aflR, two key genes of aflatoxins biosynthetic pathway. Phytochemical analysis of the ethanolic extract by GC-EIMS identified affinin/spilanthol (7.84 ± 0.27 mg g−1) as the most abundant compounds in H. longipes roots. The antifungal and anti-aflatoxigenic assays showed that affinin/spilanthol at 300 µg mL−1 produced the higher inhibition of radial growth (95%), as well as, the higher aflatoxins production inhibition (61%) in comparison to H. longipes roots (87% and 48%, respectively). qRT-PCR revealed that the expression of aflD and aflR genes showed a higher downregulation in affinin/spilanthol at 300 µg mL−1. The expression ratio of alfD was suppressed by affinin/spilanthol in 79% and aflR in 84%, while, a lower expression ratio suppressed by H. longipes was obtained, alfD (55%) and aflR (59%). Affinin/spilanthol possesses higher antifungal and anti-aflatoxigenic activity against A. parasiticus rather than H. longipes roots, and this anti-aflaxotigenic activity occurring via downregulation of the aflD and aflR genes. Thus, H. longipes roots and affinin/spilanthol can be considered potent antifungal agents against aflatoxigenic fungus, especially, affinin/spilanthol. [ABSTRACT FROM AUTHOR]

Fatty acid amide hydrolase (FAAH) is an enzyme that belongs to the amidase signature (AS) superfamily and is widely distributed in multicellular eukaryotes. FAAH hydrolyzes lipid signaling molecules – namely, N -acylethanolamines (NAEs) – which terminates their actions. Recently, the crystal structure of Arabidopsis thaliana FAAH was solved and key residues were identified for substrate-specific interactions. Here, focusing on residues surrounding the substrate-binding pocket, a comprehensive analysis of FAAH sequences from angiosperms reveals a distinctly different family of FAAH-like enzymes. We hypothesize that FAAH, in addition to its role in seedling development, also acts in an N -acyl amide communication axis to facilitate plant–microbe interactions and that structural diversity provides for the flexible use of a wide range of small lipophilic signaling molecules. Fatty acid amide hydrolase (FAAH) is the signal-terminating enzyme of the N -acylethanolamine signaling pathway with an established role in seedling development. The crystal structure of Arabidopsis thaliana FAAH was recently solved, revealing for the first time the structural features of FAAH from plants and explaining the enzyme's promiscuity toward N -acyl amide substrates. A second group of FAAH enzymes in angiosperms has been identified with conserved substitutions in the substrate-binding pocket altering the size, shape, and physicochemical properties for substrate recognition. [ABSTRACT FROM AUTHOR]

Alkamides refer to a class of natural active small-molecule products composed of fatty acids and amine groups. These compounds are widely distributed in plants, and their unique structures and various pharmacological activities have caught the attention of scholars. This review provides a collection of literatures related to the phytochemistry, pharmacological effects, pharmacokinetics, and toxicity of alkamides published in 2016 – 2022 and their summary to provide references for further development of this class of ingredients. A total of 234 components (including chiral isomers) were summarized, pharmacological activities, such as anti-inflammatory, antitumor, antidiabetic, analgesic, neuroprotective, insecticidal, antioxidant, and antibacterial, and miscellaneous properties of alkamides were discussed. In addition, the pharmacokinetic characteristics and toxicity of alkamides were reviewed. However, information on the pharmacological mechanisms of the action, drug safety, and pharmacokinetics of alkamides is limited and thus requires further investigation and evaluation. This review presents a comprehensive summarization of the phytochemistry, pharmacology, pharmacokinetics, and toxicity of alkamides reported during 2016 – 2022. [Display omitted] • Overview of alkamides with specific structures from plants (2016 – 2022). • A total of 234 compounds are summarized. • Pharmacology, pharmacokinetics, and toxicity of alkamides are concluded. [ABSTRACT FROM AUTHOR]

Alkamides are the major and characteristic chemical compounds of the plants belonging to the Piper genus. These compounds are responsible for the flavor of pepper spices and for its broad use in cuisine across many regions of the world. Humans are in contact every day with these substances, which additionally show a broad variety of pharmacological activities, making them an important research target. A large amount of NMR data for these natural products is dispersed throughout literature. Its organization will help those research groups interested in their identification and structural elucidation. This review summarizes the 1H and 13C NMR data of 268 Piper amides in a systematic and orderly way, with a discussion on their biological activities, biosynthetic aspects, and NMR analysis of typical and relevant aspects of this information. [ABSTRACT FROM AUTHOR]

Heliopsis longipes is a common spice and a medicinal plant widely used in Mexico and South America due to its mouth anesthetic, analgesic, and anti-inflammatory properties related to its spilanthol content. Previous reports have demonstrated that N -alkylamides exhibit cytotoxic effect against different cancer cell lines; however, the anti-cancer potential of the species remains unknown. Therefore, we investigated the effects of H. longipes extract (HLE) and spilanthol on HeLa, K-562, MCF-7, and HaCaT cells. HLE displayed significative antiproliferative effects and increased the rate of cell apoptosis on all cancer cell lines tested. These effects were measured by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, cell counting by flow cytometry, cell cycle analysis, Annexin V-FITC/PI activation, and nuclear DAPI staining. Significant growth inhibition was found, with emphasis to K-562 and MCF-7 cells, exhibiting IC 50 values of 87.14 and 134.25 μg/mL, respectively, without inducing substantial damage to HaCaT after 48 h of treatment. Spilanthol displayed a more pronounced inhibitory effect on cell lines, maintaining the selectivity index observed for the extract. Furthermore, real-time polymerase chain reaction revealed that HLE activated caspase 3 and caspase 8 after treatment for 48 h. Annexin V-FITC staining to detect early stage of apoptosis and DAPI staining of chromatin substantiated the cytotoxic effects. GC–MS analysis of the extract confirmed spilanthol as the major constituent present (63.94%), followed by other minor alkamides, which could also contribute to the biological effect observed. These results confirm the induction of apoptosis by Heliopsis longipes as well as the potential usefulness of the species and their alkamides as compounds to develop new anti-cancer agents. • Heliopsis longipes extract (HLE) is a rich source of N -alkylamides, mainly of bioactive spilanthol. • HLE showed a higher antiproliferative and better selectivity index established for K-562 cancer cells. • Extract was not deleterious for the non-cancerous HaCaT cells. • HLE-induced apoptosis occur via activation of caspases 3 and 8. [ABSTRACT FROM AUTHOR]

Abstract Ethno–pharmacological relevance Tropaeolum tuberosum , commonly known as "Mashua", is one of the plants most frequently used by Andean (Peruvian–Bolivian) people as food and medicine. It is used as a remedy against a wide range of diseases, especially those related with inflammation. Objectives This study aims to identify compounds active against inflammatory related conditions. Materials and methods A bioassay–guided isolation of anti–inflammatory compounds from black and purple tubers of T. tuberosum was performed measuring TNF–α and NF–κB production in THP–1 monocytic cells. Results The bioassay–guided isolation led to one active compound from purple T. tuberosum , N–oleoyldopamine (1), and another active compound from black T. tuberosum , N–(2–Hydroxyethyl)–7Z,10Z,13Z,16Z–docosatetraenamide (2). Both compounds displayed anti–TNF–α activity with IC 50 values of 3.12 ± 0.19 μM and 1.56 ± 0.15 μM, respectively. Also, both compounds suppressed NF–κB with IC 50 of 3.54 ± 0.02 μM and 1.77 ± 0.07 μM, respectively. Conclusions We identified bioactive compounds from purple and black Tropaeolum tuberosum responsible for their anti–inflammatory activity: N– oleoyldopamine (1) and N– (2 – Hydroxyethyl) – 7Z,10Z,13Z,16Z – docosatetraenamide (2). This is the first report which isolates these compounds from T. tuberosum and describes their anti–inflammatory activities. Graphical abstract fx1 [ABSTRACT FROM AUTHOR]

Alkamides have been observed to interact in different ways in several superior organisms and have been used in traditional medicine in many countries e.g., to relieve pain. Previous studies showed that affinin when applied to other plant species induces prominent changes in the root architecture and induces transcriptional adjustments; however, little is known about the metabolic pathways recruited by plants in response to alkamides. Previous published work with Arabidopsis seedlings treated in vitro with affinin at 50 µM significantly reduced primary root length. In tomato seedlings, that concentration did not reduce root growth but increase the number and length of lateral roots. Non-targeted metabolomic analysis by Gas Chromatography couplet to Mass Spectrometry (GC/EIMS) showed that, in tomato seedlings, affinin increased the accumulation of several metabolites leading to an enrichment of several metabolic pathways. Affinin at 100 µM alters the accumulation of metabolites such as organic acids, amino acids, sugars, and fatty acids. Finally, our results showed a response possibly associated with nitrogen, GABA shunt and serine pathways, in addition to a possible alteration in the mitochondrial electron transport chain (ETC), interesting topics to understand the molecular and metabolic mechanisms in response to alkamide in plants.

The current therapies of leishmaniasis, the second most widespread neglected tropical disease, have limited effectiveness and toxic side effects. In this regard, natural products play an important role in overcoming the current need for new leishmanicidal agents. The present study reports a bioassay-guided fractionation of the ethanolic extract of leaves of Piper pseudoarboreum against four species of Leishmania spp. promastigote forms, which afforded six known alkamides (1–6). Their structures were established on the basis of spectroscopic and spectrometric analysis. Compounds 2 and 3 were identified as the most promising ones, displaying higher potency against Leishmania spp. promastigotes (IC50 values ranging from 1.6 to 3.8 µM) and amastigotes of L. amazonensis (IC50 values ranging from 8.2 to 9.1 µM) than the reference drug, miltefosine. The efficacy of (E)-piplartine (3) against L. amazonensis infection in an in vivo model for cutaneous leishmaniasis was evidenced by a significant reduction of the lesion size footpad and spleen parasite burden, similar to those of glucantime used as the reference drug. This study reinforces the therapeutic potential of (E)-piplartine as a promising lead compound against neglected infectious diseases caused by Leishmania parasites.

Recently, several publications revealed the presence of potentially active volatile substances in the roots of yarrow species. Though their specific function is not clear, they are supposed to have an important role in plant-environment interactions. In the present paper, chemical composition of hydrodistilled essential oil (EO), headspace (HS) volatiles and dichloromethane extracts (DE) of the roots of 10 different Achillea collina Becker accessions were analysed by GC-FID and GC-MS and compared. Volatility and solubility of active ingredients and the sensitivity of extraction methods resulted in different chemical compositions. Only a few of the main constituents (alismol, (E)-β-farnesene, β-sesquiphellandrene and neryl esters) were found in each extract type. In the EOs, the main compound was component with RI 1874 tentatively identified as heptadecen-7-one (28.9-43.0%). Albene (20.8-52.1%) and β-pinene (8.3-47.1%) were the most represented constituents among HS volatiles. The main and universal constituents of DEs were component with RI 1874 tentatively identified as heptadecen-7-one, linoleic acid, 2,4,6-decatrienoic acid piperideide, sterols (RI 3280, 3338 and 3360) and a triterpene (RI 3456) which together amounted 34.4-61.7% of the extracts. [ABSTRACT FROM AUTHOR]

Three new alkamides, zanthoamides G-I ( 1-3 ), together with ten known compounds, araliopsine, skimmianine, N -methylplatydesminium cation, isoplatydesmine, myrtopsine, atanine, N -methylatanine, sesamin, hesperetin and hesperidin, were isolated from the fruits of Zanthoxylum zanthoxyloides . Their structures were elucidated by spectroscopic means. All isolated compounds were assessed for their cytotoxicity against A549, MCF7, PC3 and PNT2 cell lines. Among the alkamides, only zanthoamide G ( 1 ) showed low level of cytotoxicity against MCF7 cells. [ABSTRACT FROM AUTHOR]

Background Spilanthol is a bioactive alkamide widespread in Asteraceae and Piperaceae plant species. The species from Asteraceae are famous because of their sensorial anesthetic and spicy properties. One of these plants is Acmella oleracea, popularly known as jambu, is widely used as a spice in Brazilian cuisine and as a folk remedy. Many scientific papers can be found in the literature regarding the biological importance of spilanthol and its methods of extraction. However, to date, none of the studies has presented a technological mapping of patents involving this natural product. Scope and approach The present study aimed to compile data relating the state of the art on patents filed or granted between 1996 and 2016 involving spilanthol. To that end, a patent research was performed in the international patent database Patentscope, in a period of 20 years (1996–2016), using the keyword spilanthol. Key findings Patents were separated into four groups of interest, according to the technological use of spilanthol: a) pharmacological properties; b) use in cosmetics; c) methods for obtaining and d) sensorial effects. Only 91 patents were found regarding the first three groups, which showed that there is a scope for the development of new technologies. The sensorial properties of spilanthol are widely used in oral care compositions, personal products, cleaning products, foodstuffs and beverages. Conclusions This study presents different technological approaches to apply spilanthol, which helps to visualize opportunities and to boost innovation for new products. [ABSTRACT FROM AUTHOR]

In previous studies the aerial parts of Achillea fragrantissima were found to have substantial antileishmanial and antitrypanosomal activity. A bioassay-guided fractionation of a dichloromethane extract yielded the isolation of the essential anti-trypanosomal compounds of the plant. Seven sesquiterpene lactones (including Achillolide-A), two flavonoids, chrysosplenol-D and chrysosplenetine, and four alkamides (including pellitorine) were identified. This is the first report for the isolation of the sesquiterpene lactones 3 and 4 , chrysosplenetine and the group of alkamides from this plant. Bioevaluation against Trypanosoma brucei brucei TC221 (T.b brucei) using the Alamar-Blue assay revealed the novel alkamide 13 to have an IC 50 value of 40.37 μM. A compound library, derived from the alkamide pellitorine ( 10 ), was synthesized and bioevaluated in order to find even more active substances. The most active compounds 26 and 27 showed activities in submicromolar concentrations and selectivity indices of 20.1 and 45.6, respectively, towards macrophage cell line J774.1 . Toxicity of 26 and 27 was assessed using the greater wax moth Galleria mellonella larvae as an in vivo model. No significant toxicity was observed for the concentration range of 1.25–20 mM. [ABSTRACT FROM AUTHOR]

Black pepper ( Piper nigrum) contains a variety of alkamides. Among them, piperine has been reported to have antidepressant-like effects in chronically stressed mice, but little is known about the biological activity of other alkamides. In this study, we investigated the effects of alkamides from white pepper ( P. nigrum) on neuronal cells. Twelve alkamides were isolated from white pepper MeOH extracts, and their chemical structures were identified by NMR and MS analyses. The compounds were subjected to assays using the luciferase-reporter gene under the control of the BDNF promoter or cAMP response element in mouse neuroblastoma Neuro-2a cells. In both assays, marked reporter-inducing activity was observed for piperine ( 1), piperettine ( 2) and piperylin ( 7), all of which have in common an ( E)-5-(buta-1,3-dien-1-yl)benzo[d] [1, 3] dioxole moiety. Piperettine ( 2) and piperylin ( 7) tended to increase endogenous BDNF protein levels. Furthermore, piperylin ( 7) promoted retinoic acid-induced neurite outgrowth. These results suggest that piperylin ( 7), or analogues thereof, may have a beneficial effect on disorders associated with dysregulation of BDNF expression, such as depression. [ABSTRACT FROM AUTHOR]

Bragantina and Cingapura are the main black pepper (Piper nigrum L.) cultivars and the Pará state is the largest producer in Brazil with about 90% of national production, representing the third largest production in the world. The infection of Fusarium solani f. sp. piperis, the causal agent of Fusarium disease in black pepper, was monitored on the cultivars Bragantina (susceptible) and Cingapura (tolerant), during 45 days' post infection (dpi). Gas Chromatography-Mass spectrometry (GC-MS) analysis of the volatile concentrates of both cultivars showed that the Bragantina responded with the production of higher contents of α-bisabolol at 21 dpi and a decrease of elemol, mostly at 30 dpi; while Cingapura displayed an decrease of δ-elemene production, except at 15 dpi. The phenolic content determined by the Folin Ciocalteu method showed an increase in the leaves of plants inoculated at 7 dpi (Bragantina) and 7-15 dpi (Cingapura); in the roots, the infection caused a phenolic content decrease in Bragantina cultivar at 45 dpi and an increase in the Cingapura cultivar at 15, 30 and 45 dpi. High Performance Liquid Chromatography-Mass spectrometry (HPLC-MS) analysis of the root extracts showed a qualitative variation of alkamides during infection. The results indicated that there is a possible relationship between secondary metabolites and tolerance against phytopathogens. [ABSTRACT FROM AUTHOR]

Objective To establish the role of TRPV1 receptor in the antinociceptive effect of natural alkamides (i.e. affinin, longipinamide A, longipenamide A and longipenamide B) isolated from Heliopsis longipes (A. Gray) S.F. Blake and some related synthetic alkamides (i.e. N-isobutyl-feruloylamide and N-isobutyl-dihydroferuloylamide). Methods The orofacial formalin test was used to assess the antinociceptive activity of natural (1-30 μg, orofacial region) and synthetic alkamides (0.1-100 μg, orofacial region). The alkamide capsaicin was used as positive control, while capsazepine was used to evaluate the possible participation of TRPV1 receptor in alkamide-induced antinociception. Key findings Natural (1-30 μg) and synthetic (0.1-100 μg) alkamides administered to the orofacial region produced antinociception in mice. The antinociceptive effect induced by affinin, N-isobutyl-feruloylamide and N-isobutyl-dihydroferuloylamide was antagonized by capsazepine but not by vehicle. Conclusions These results suggest that alkamide affinin, longipinamide A, longipenamide A and longipenamide B isolated from Heliopsis longipes as well as the synthesized analogue compounds N-isobutyl-feruloylamide and N-isobutyl-dihydroferuloylamide produce their effects by activating TRPV1 receptor and they may have potential for the development of new analgesic drugs for the treatment of orofacial pain. [ABSTRACT FROM AUTHOR]

[Display omitted] • Validated method for simultaneous determination of six bioactive alkamides in Piper longum. • Green analytical chemistry approach was applied for screening of bioactive phytochemical from underutilized plant parts of highly traded spices. • Anti-obesity potential of P. longum roots is assigned to pancreatic lipase inhibitory action of piplartine and other related alkamides. • Greenness assessment of method was done by multi-approaches viz., NEMI, ESA, GAPI and AGREE tools. • Method enables sustainable utilization of agro-waste of P. longum for functional-food and therapeutic application. The substantial structural similarity of alkamides poses a challenge in the chromatographic separation for simultaneous quantification of bioactive alkaloids in agro-waste of Piper longum. Here, we report a novel HPTLC method for the simultaneous quantitation of six alkamides, viz., pellitorine (1) , piperanine (2) , piperine (3) , piperdardine (4) , piplartine (5) , and piperlonguminine (6) in Piper longum. PRISMA approach was applied for optimum separation on silica gel 60 F 254 plates using n -hexane-dichloroethane-diethylamine (7.8:1.2:0.5, v/v/v) as the solvent system. In addition to R f and colour visualization, the specificity of determination was demonstrated by UV, and mass spectral matching. The method was consistent with the Beer's law over the 1–5 µg/band range. The detection limits and the limits of quantification are in the range of 0.073–0.531, and 0.243–0.769 µg for pellitorine (1) , piperanine (2) , piperine (3) , piperdardine (4) , piplartine (5), and piperlonguminine (6) ; respectively. The proposed method was successfully applied to determine the six cited alkamides with mean recoveries ranging from 98.81 to 100.05 %, and intra- and inter-day precisions with relative standard deviations below 2 %. Moreover, the greenness was investigated using National Environmental Methods Index (NEMI), Eco-scale Assessment (ESA), Green Analytical Procedure Index (GAPI), and Analytical GREEness metric (AGREE) metrics revealing the current HPTLC method environmentally benign and energy efficient. It is the first report of an analytical method that supports precise, high-throughput, and simultaneous quantification of six alkamides (1 – 6) in Piper longum roots with application in food and pharmaceutical. [ABSTRACT FROM AUTHOR]

A new aristolactam, aristolactam 9-O-β-D-glucopyranosyl-(1→2)-β-D-glucoside, and two alkamides, N-cis- and N-trans-p-coumaroyl-3-O-methyldopamine, were isolated from stems of Aristolochia gigantea, together with the known compounds allantoin, E-nerolidol, β-sitosterol, (+)-kobusin, (+)-eudesmin, trans-N-feruloyltyramine, trans-N-coumaroyltyramine, trans-N-feruloyl-3-O-methyldopamine, aristolactam Ia-N-β-D-glucoside, aristolactam Ia 8-β-D-glucoside, aristolactam IIIa, and magnoflorine. Their structures were determined by spectroscopic analyses.

The synthesis of the alkamides 2Z,4E-undeca-2,4-dien-8,10-diynoic acid isobutyl amide (1) and 2Z,4E-undeca-2,4-dien-8,10-diynoic acid isobutyl amide (5) was accomplished by organometallic coupling followed by introduction of the doubly unsaturated amide moiety. The distribution of these two amides in accessions of the nine species of Echinacea was determined.

The Echinacea genus is exemplary of over 30 plant families that produce a set of bioactive amides, called alkamides. The Echinacea alkamides may be assembled from two distinct moieties, a branched-chain amine that is acylated with a novel polyunsaturated fatty acid. In this study we identified the potential enzymological source of the amine moiety as a pyridoxal phosphate-dependent decarboxylating enzyme that uses branched-chain amino acids as substrate. This identification was based on a correlative analysis of the transcriptomes and metabolomes of 36 different E. purpurea tissues and organs, which expressed distinct alkamide profiles. Although no correlation was found between the accumulation patterns of the alkamides and their putative metabolic precursors (i.e., fatty acids and branched-chain amino acids), isotope labeling analyses supported the transformation of valine and isoleucine to isobutylamine and 2-methylbutylamine as reactions of alkamide biosynthesis. Sequence homology identified the pyridoxal phosphate-dependent decarboxylase-like proteins in the translated proteome of E. purpurea. These sequences were prioritized for direct characterization by correlating their transcript levels with alkamide accumulation patterns in different organs and tissues, and this multi-pronged approach led to the identification and characterization of a branched-chain amino acid decarboxylase, which would appear to be responsible for generating the amine moieties of naturally occurring alkamides. [ABSTRACT FROM AUTHOR]

The anticholinesterase and antioxidant effects of five different extracts of Piper nigrum were evaluated. Twenty-one known alkamides were isolated from active ethyl acetate extract and investigated for their cholinesterase inhibitory and antioxidant effects. Among them, piperine (2), piperettine (5) and piperettyline (20) exhibited dual inhibition against AChE and BChE, and feruperine (18) was the most potent selective inhibitor of BChE. Molecular docking simulation was performed to get insight into the binding interactions of the ligands and enzymes. In addition, N-trans-feruloyltyramine (3) contributed to the strongest DPPH radical-scavenging activity. The self-induced Aβ aggregation inhibition of 2, 5 and 18 was further evaluated. Results indicated that some alkamides could be multifunctional lead candidates for Alzheimer's disease therapy. [ABSTRACT FROM AUTHOR]

Two simple synthetic approaches were developed for the total synthesis of δ-sanshool, an isobutylamide characterized by a C14 pentaunsaturated chain with all trans double bonds and proposed as a promising lead for the treatment of type-1 diabetes due to its dual activity on cannabinoid (CB) receptors. The syntheses are based on a suitably protected core fragment derived from 1,4-butanediol. These strategies also enable the preparation of small libraries of chemical analogues modified at either the polyunsaturated alkyl chain or the amidic head for use in SAR studies. [ABSTRACT FROM AUTHOR]

Maca, Lepidium meyenii Walpers (Brassicaceae), is an annual herbaceous plant native to the high plateaus of the Peruvian central Andes. Its underground storage hypocotyls have been a traditional medicinal agent and dietary staple since pre-Columbian times. Reported properties include energizing and fertility-enhancing effects. Published reports have focused on the benzylalkamides (macamides) present in dry hypocotyls as one of the main bioactive components. Macamides are secondary amides formed by benzylamine and a fatty acid moiety, with varying hydrocarbon chain lengths and degree of unsaturation. Although it has been assumed that they are usually present in fresh undamaged tissues, analyses show them to be essentially absent from them. However, hypocotyls dried by traditional Andean postharvest practices or industrial oven drying contain up to 800 μg g −1 dry wt (2.3 μmol g −1 dry wt) of macamides. In this study, the generation of macamides and their putative precursors were studied during nine-week traditional drying trials at 4200 m altitude and in ovens under laboratory conditions. Freeze–thaw cycles in the open field during drying result in tissue maceration and release of free fatty acids from storage and membrane lipids up to levels of 1200 μg g −1 dry wt (4.3 μmol g −1 dry wt). Endogenous metabolism of the isothiocyanates generated from glucosinolate hydrolysis during drying results in maximal benzylamine values of 4300 μg g −1 dry wt (40.2 μmol g −1 dry wt). Pearson correlation coefficients of the accumulation profiles of benzylamine and free fatty acid to that of macamides showed good values of 0.898 and 0.934, respectively, suggesting that both provide sufficient substrate for amide synthesis during the drying process. [ABSTRACT FROM AUTHOR]

Heliopsis longipes has been recognized as a potential source of insecticidal compounds called alkamides, which can be used to control populations of insect vector transmitters of several diseases that affect the human health. To determine the insecticidal activity of H . longipes against Anopheles albimanus and Aedes aegypti , crude extract of H. longipes roots and affinin were obtained. Catalytic reduction of affinin was performed to obtain two reduced amides, N -isobutil-2 E -decenamide and N -isobutil-decanamide. Crude extract, affinin and its reduced amides were evaluated against third instar larvae of An. albimanus and Ae. aegypti . Results show that crude extract of H. longipes possess larvicidal activity against larval stage of An. albimanus and Ae. aegypti . This effect could be attributed to affinin, on which the conjugated double bonds present in the structure of the molecule are necessary to maintain larvicidal activity. This study demonstrated the potential of H. longipes to control larval stage of An. albimanus and Ae. aegypti , transmitter vectors of malaria and dengue fever, respectively. [ABSTRACT FROM AUTHOR]

The impact of the ploidy level on biomass accumulation and the production of high-value secondary metabolites was studied in Echinacea purpurea (L.) Moench. Tetraploid E. purpurea was obtained by treating diploid explants with colchicine. The morphology, biomass yield, the contents of caffeic acid derivatives and alkamides, and the activities of phenylalanine ammonia-lyase (PAL) and cinnamate 4-hydroxylase (C4H) were compared between diploid plants and tetraploid plants of E. purpurea. The total fresh root weight and total dry root weight of the tetraploid plants were 39.32 and 40.48 % higher than those of the diploid plants, respectively. The chemical profiles of the diploid and tetraploid E. purpurea plants were similar, as determined through a comparison of their FTIR spectra and second derivative spectra. The caffeic acid derivatives and alkamides in the diploid and tetraploid plants were determined by HPLC. The tetraploid plants had higher contents of both of these types of molecules. In addition, the tetraploid plants had higher PAL and C4H activities compared with the diploid plants. The enhancement in the PAL and C4H activities was accompanied with an increase in the cichoric acid content, which indicates that the induction of polyploidy in E. purpurea resulted in higher PAL and C4H expression and promoted the biosynthesis of cichoric acid. Therefore, the induction of polyploidy may be a valid strategy to achieve a higher yield of biomass and bioactive compounds in E. purpurea. [ABSTRACT FROM AUTHOR]