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A study proposing cyclodextrins as eco-friendly compounds to enhance the physicochemical properties of phthalimide-lactones to produce complexes inducing the germination of parasitic weeds even without using organic co-solvents.

Strigolactones (SLs) are natural products with promising applications as agrochemicals to prevent infestation with parasitic weeds due to their ability to trigger seed germination. However, their use is still limited because of the low yields in which they are isolated from natural sources. As such, numerous studies have led to strategies for obtaining them, and various structural analogues, by organic synthesis. These analogues have focused attention on the study of SLs, as some of them are easier to synthesize and possess enhanced properties, such as the level of bioactivity. This review provides an overview of the synthesis of SLs, subsequently focusing on the production of analogues with the canonical structure. The germinating activity of the compounds is also described herein, with positive effects on different species of the problematic genera Striga, Orobanche and Phelipanche having been found. The highly active analogue GR24 is currently the most widely studied in the literature, and relevant structural-activity relationships have been proposed as a result of the study of derivatives functionalized in different positions. Analogues based on other natural SLs such as strigol and orobanchol have also been developed, as have some novel canonical SLs derived from eudesmanolide or guaianolide sesquiterpene lactones. This review aims to provide useful information for the development of bioactive compounds applicable in new generation herbicides, in an attempt to employ similar compounds to those produced naturally in ecosystems that provoke effective herbicide effects at low concentrations.

Natural products have been postulated as an alternative to the use of synthetic herbicides in pest control. The latter compounds have caused numerous problems and these include the appearance of resistance to such herbicides. Aminophenoxazinones are natural products that have shown multiple biological activities, such as pharmacological or phytotoxic effects. In the case of phytotoxicity, the mode of action of aminophenoxazinones has not been widely exploited in agriculture and resistant weeds have not been reported to date. This fact makes aminophenoxazinones promising candidates in the development of herbicides. In the study reported here, seven aminophenoxazinone derivatives have been synthesized and their phytotoxicity has been evaluated on wheat coleoptiles and two important agricultural weeds (Lolium rigidum and Portulaca oleracea). Several derivatives have shown phytotoxic activity, which is similar to the positive control pendimethalin, and even higher in some cases at the highest concentrations tested. The most affected parameter in weeds was root length and the most susceptible weed was P. oleracea. Compound 2, in which nitrogen atoms are present in the heterocycles, was the most active and this was followed by compound 1. Modifications at C-8 led to a reduced activity, with the exception of the nitro compound on the root length of P. oleracea. However, the phytotoxicity also increased on introducing an iodo-substituent at C-4. The results highlight aminophenoxazinones as promising candidates in the development of natural herbicides.

C-17-sesquiterpenoids are a group of natural products that have been recently discovered. These compounds have the peculiarity of lacking the alpha,beta-methylene butyrolactone system, which is known to be quite relevant for many of the biological activities reported for sesquiterpene lactones. Unfortunately, the biological interest of C-17-sesquiterpenoids has not been studied in-depth, mainly due to the poor isolation yields in which they can be obtained from natural sources. Therefore, in order to allow a deeper study of these novel molecules, we have worked out a synthetic pathway that provides C-17-sesquiterpenoids in enough quantities from easily accessible sesquiterpene lactones to enable a more thorough investigation of their bioactivities. With this synthesis method, we have successfully synthesized, for the first time, three natural C-17-sesquiterpenoids, pertyolides A, B, and C, with good overall yields. Furthermore, we have also evaluated their phytotoxicity against etiolated wheat coleoptiles and corroborated that pertyolides B and C present strong phytotoxic activity., This research was supported by the Ministerio de Economia, Industria y Competitividad (MINEICO), Spain, AGL2017-88083-R.

Natural products are a promising source for the development of new pesticides with alternative mechanisms of action. In this study, we evaluated the phytotoxic and antifungal activity of a novel family of natural CMany tested compounds exhibited a strong phytotoxic activity. Lappalone and pertyolide B were the most potent molecules from the tested group. Lappalone displayed a strong inhibition profile against selected weed species, reaching a half-maximal inhibitory concentration (ICThe bioassays revealed that frequently the presence of the α-methylene-γ-butyrolactone system is not essential for the bioactivities of sesquiterpene lactones, and suggest that C

The encapsulation of bioactive natural products has emerged as a relevant tool for modifying the poor physicochemical properties often exhibited by agrochemicals. In this regard, natural guaiane-type sesquiterpene lactones isolated from Cynara cardunculus L. have been encapsulated in a core/shell nanotube@agrochemical system. Monitoring of the F and O signals in marked sesquiterpenes confirmed that the compound is present in the nanotube cavity. These structures were characterized using scanning transmission electron microscopy–X-ray energy-dispersive spectrometry techniques, which revealed the spatial layout relationship and confirmed encapsulation of the sesquiterpene lactone derivative. In addition, biological studies were performed with aguerin B (1), cynaropicrin (2), and grosheimin (3) on the inhibition of germination, roots, and shoots in weeds (Phalaris arundinacea L., Lolium perenne L., and Portulaca oleracea L.). Encapsulation of lactones in nanotubes gives better results than those for the nonencapsulated compounds, thereby reinforcing the application of fully organic nanotubes for the sustainable use of agrochemicals in the future.

Strigolactones are natural products that are exuded by plants and stimulate parasitic weed germination. Their use in herbicides is limited since they are produced in small quantities, but the synthesis of bioactive analogues provides an alternative source. In this work, eleven analogues have been synthesized. Among them, nine compounds belong to a novel family named eudesmanestrigolactones. The procedure is short (3-6 steps), the starting materials are isolated on a multigram scale, and global yields are up to 8%, which significantly enhance isolated yields. In bioassay, the compounds germinated high percentages of Phelipanche ramosa, Orobanche cumana, and Orobanche crenata seeds, even at nanogram doses (100 nM). Bioactivity was stereochemistry-dependent, and it was discussed in terms of the presence and geometry of the enol ether, orientation of the butenolide, and unsaturation of ring A. The reported compounds provide a set of readily obtained allelochemicals with potential applications as preventive herbicides.

Weeds have been a major threat in agriculture for several generations as they lead to decreases in productivity and cause significant economic losses. Parasitic plants are a specific type of weed causing losses in crops of great relevance. A new strategy has emerged in the fight against parasitic plants, which is called 'suicidal germination' or the 'honey-pot strategy'. Regarding the problem of weed control from an ecological point of view, it is interesting to investigate new natural compounds with allelopathic activity with the aim of developing new natural herbicides that can inhibit the growth of weeds without damaging the environment. Safflower crops have been affected by parasitic plants and weeds and, as a consequence, the secondary metabolites exuded by safflower roots have been studied. The sesquiterpene lactone dehydrocostuslactone was isolated and characterised, and the structurally related costunolide was identified by UHPLC-MS/MS in safflower root exudates. These sesquiterpene lactones have been shown to stimulate germination of Phelipanche ramosa and Orobanche cumana seeds. In addition, these compounds were phytotoxic on three important weeds in agriculture, namely Lolium perenne, Lolium rigidum and Echinochloa crus-galli. The exudation of the strigolactones solanacol and fabacyl acetate have also been confirmed by UHPLC-MS/MS. The study reported here contributes to our knowledge of the ecological role played by some secondary metabolites. Moreover, this knowledge could help identify new models for the development of future agrochemicals based on natural products.

Nitrogen (N) and phosphorus (P) are among the most important macronutrients for plant growth and development, and the most widely used as fertilizers. Understanding how plants sense and respond to N and P deficiency is essential to optimize and reduce the use of chemical fertilizers. Strigolactones (SLs) are phytohormones acting as modulators and sensors of plant responses to P deficiency. In the present work, we assess the potential role of SLs in N starvation and in the N-P signalling interplay. Physiological, transcriptional and metabolic responses were analysed in wild-type and SL-deficient tomato plants grown under different P and N regimes, and in plants treated with a short-term pulse of the synthetic SL analogue 2 '-epi-GR24. The results evidence that plants prioritize N over P status by affecting SL biosynthesis. We also show that SLs modulate the expression of key regulatory genes of phosphate and nitrate signalling pathways, including the N-P integrators PHO2 and NIGT1/HHO. The results support a key role for SLs as sensors during early plant responses to both N and phosphate starvation and mediating the N-P signalling interplay, indicating that SLs are involved in more physiological processes than so far proposed., This work was supported by grants RTI2018-094350-B-C31 from the Spanish National R&D Plan of the Ministry of Science, Innovation and Universities (MICIU) and the European Regional Development Fund (ERDF) 'a way a making Europe'. JL was supported by PhD fellowship BES-2016-077850. The contribution of NM and MJ was supported by the Research Development Programme RVO67985939 of Czech Academy of Sciences. We thank Dr Koichi Yoneyama and Dr Xiaonan Xie (Weed Science Centre, Utsunomiya University, Japan) for kindly providing the natural SLs used to set up their analytical quantification and the synthetic SL analogue 2-epi-GR24. We also thank Dr Harro Bouwmeester (Faculty of Science, University of Amsterdam) for the seeds of the SL-deficient line SlCCD8-RNAi L09. We acknowledge the Scientific Instrumentation Service (SIC) and Nitrogen/Carbon Analysis Service (SANC) of the EEZ-CSIC for technical support in the nutrient analysis.

3D printing is a manufacturing technique that is transforming numerous industrial sectors, particularly where it is key tool in the development and fabrication of medicinees that are personalised to the individual needs of patients. Most 3D printers are relatively large, require trained operators and must be located in a pharmaceutical setting to manufacture dosage forms. In order to realise fully the potential of point-of-care manufacturing of medicines, portable printers that are easy to operate are required. Here, we report the development of a 3D printer that operates using a mobile smartphone. The printer, operating on stereolithographic principles, uses the light from the smartphone's screen to photopolymerise liquid resins and create solid structures. The shape of the printed dosage form is determined using a custom app on the smartphone. Warfarin-loaded Printlets (3D printed tablets) of various sizes and patient-centred shapes (caplet, triangle, diamond, square, pentagon, torus, and gyroid lattices) were successfully printed to a high resolution and with excellent dimensional precision using different photosensitive resins. The drug was present in an amorphous form, and the Printlets displayed sustained release characterises. The promising proof-of-concept results support the future potential of this compact, user-friendly and interconnected smartphone-based system for point-of-care manufacturing of personalised medications.

Piptocarpha rotundifolia (Less.) Baker stands out as one of the species with the highest frequency, density, and relative dominance in the Cerrado formations. However, no phytochemical studies have been carried out with this species to date. The aim of this study was to evaluate the phytotoxic activity of P. rotundifolia leaves in the search of new environmentally friendly tools for weed control. Thus, a wheat coleoptile and phytotoxic bioassay, using relevant agricultural weeds, was used to identify the most active extracts and fractions. The subsequent purification process allowed the isolation of 11 compounds, the phytotoxicity of which was evaluated in terms of wheat coleoptile elongation and with the most sensitive weeds. Piptocarphin A was found to be the major compound and the most active. To confirm its phytotoxic potential, the effect on Ipomea grandifolia grown in a hydroponic culture and on metaxylem cells was studied. The results obtained in this study demonstrate that the inhibitory activity displayed by P. rotundifolia leaf extract is mainly due to the presence of piptocarphin A. The phytotoxicity shown by P. rotundifolia leaf extract, and the isolated compounds, on weeds could provide new tools for weed control in agricultural fields., This research was supported by CAPES - Coordination for the Improvement of Higher Education Personnel (Brazil) (Project 88881.119937/2016-01) and "Ministerio de Economia, Industria y Competitividad" (MINEICO), Spain, Project AGL201788-083-R.

Higher Pi acquisition efficiency in wheat was related to an improved root system under Pi starvation, allowing higher Pi uptake. This response correlated with faster modulation of the IPS1–miR399–PHO2 pathway and strigolactone levels., Inorganic phosphorus (Pi) fertilizers are expected to become scarce in the near future; so, breeding for improved Pi acquisition-related root traits would decrease the need for fertilizer application. This work aimed to decipher the physiological and molecular mechanisms underlying the differences between two commercial wheat cultivars (Crac and Tukan) with contrasting Pi acquisition efficiencies (PAE). For that, four independent experiments with different growth conditions were conducted. When grown under non-limiting Pi conditions, both cultivars performed similarly. Crac was less affected by Pi starvation than Tukan, presenting higher biomass production, and an enhanced root development, root:shoot ratio, and root efficiency for Pi uptake under this condition. Higher PAE in Crac correlated with enhanced expression of the Pi transporter genes TaPht1;2 and TaPht1;10. Crac also presented a faster and higher modulation of the IPS1–miR399–PHO2 pathway upon Pi starvation. Interestingly, Crac showed increased levels of strigolactones, suggesting a direct relationship between this phytohormone and plant P responses. Based on these findings, we propose that higher PAE of the cultivar Crac is associated with an improved P signalling through a fine-tuning modulation of PHO2 activity, which seems to be regulated by strigolactones. This knowledge will help to develop new strategies for improved plant performance under P stress conditions.

Natural product anhydrojudaicin (7) is a eudesmanolide that has been synthesized from costunolide (1) in three steps with good yield, simplifying procedures available in the literature. The key step was the efficient oxidation and rearrangement using 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ). Following the same methodology, 11,13-dehydroanhydrojudaicin (8) was prepared for the first time. All compounds were characterized and tested in three specific bioassays: phytotoxicity bioassays on wheat coleoptile and on weed seeds (Amaranthus viridis, Echinochloa crus-galli and Panicum maximum); as well as bioassay of germination of parasitic weed seeds of broomrape (Orobanchaceae). The final products showed better activity profiles than the starting eudesmanolide in all bioassays. The data allow us to propose compounds 7 and 8 as leads for new natural product-based agrochemicals.

Aminophenoxazinones are degradation products resulting from the metabolism of different plant species, which comprise a family of natural products well known for their pharmacological activities. This review provides an overview of the pharmacological properties and applications proved by these compounds and their structural derivatives during 2000–2021. The bibliography was selected according to our purpose from the references obtained in a SciFinder database search for the Phx-3 structure (the base molecule of the aminophenoxazinones). Compounds Phx-1 and Phx-3 are among the most studied, especially as anticancer drugs for the treatment of gastric and colon cancer, glioblastoma and melanoma, among others types of relevant cancers. The main information available in the literature about their mechanisms is also described. Similarly, antibacterial, antifungal, antiviral and antiparasitic activities are presented, including species related directly or indirectly to significant diseases. Therefore, we present diverse compounds based on aminophenoxazinones with high potential as drugs, considering their levels of activity and few adverse effects.

Several strategies have been proposed to control parasitic plants and these include biological control, the use of herbicides, and suicidal germination or trap crops. In the case of sunflower, the most effective solution is genetic resistance. Nevertheless, the use of resistant cultivars is followed by the appearance of new and more virulent races of the parasite that overcome the existing sources of resistance. For this reason, it is necessary to increase our knowledge of the mechanisms involved in the resistant varieties. In this study, the presence of compounds involved in pre-attachment resistance mechanisms in sunflower varieties was analyzed. The production of stimulators of the germination of parasitic plant seeds and the concentration of the haustorial elongation inhibitor, scopoletin, were measured in exudates of resistant and susceptible sunflower varieties. It was found that dehydrocostuslactone and orobanchyl acetate are not involved in the resistance of the sunflower varieties studied. The results demonstrate that costunolide, heliolactone, and scopoletin are related to sunflower resistance. The sunflower varieties studied do not use all available options to fight parasitic plants. This could be one of the reasons that sunflower resistance is rapidly overcome by broomrape.

Strigolactones (SLs) are a prime example of allelochemicals, promoting parasitic plant germination and certain hyphal branching factors associated to the growth of symbiotic arbuscular mycorrhizal fungi (AMF). However, the study of SLs is complex, and various issues have yet to be studied in depth. This review intends to provide an overview of the works that have been conducted on the identification, isolation, and evaluation of the allelopathic activity of natural canonical and non-canonical SLs on parasitic weeds and AMF growth. These topics were related with their application in agriculture through trap crops, suicidal germination or intercropping strategies. The high applicability of SLs in agriculture, for example, as preventing herbicides for parasitic weed control, has increased the interest for these compounds and the number of research articles published. This review updates and discusses the last findings in this field, with special emphasis in the results published since 2015, using tables and graphs to summarize and discuss that information. The promising results and conclusions obtained from the bioassays herein presented provide a good reason to encourage and support further research works on these natural products, which must also consider the disadvantages or current limitations that SLs present., This work was supported by the "Ministerio de Economia, Industria y Competitividad" (MINEICO), Spain, Project AGL2017-88-083-R; and by grants RTI2018-094350-B-C31 from the Spanish National R&D Plan of the Ministry of Science, Innovation and Universities Economy and Competitiveness (MICIU) and the European Regional Development Fund (ERDF).

Strigolactones (SLs) are important ex-planta signalling molecules in the rhizosphere, promoting the association with beneficial microorganisms, but also affecting plant interactions with harmful organisms. They are also plant hormones in-planta, acting as modulators of plant responses under nutrient-deficient conditions, mainly phosphate (Pi) starvation. In the present work, we investigate the potential role of SLs as regulators of early Pi starvation signalling in plants. A short-term pulse of the synthetic SL analogue 2′-epi-GR24 promoted SL accumulation and the expression of Pi starvation markers in tomato and wheat under Pi deprivation. 2′-epi-GR24 application also increased SL production and the expression of Pi starvation markers under normal Pi conditions, being its effect dependent on the endogenous SL levels. Remarkably, 2′-epi-GR24 also impacted the root metabolic profile under these conditions, promoting the levels of metabolites associated to plant responses to Pi limitation, thus partially mimicking the pattern observed under Pi deprivation. The results suggest an endogenous role for SLs as Pi starvation signals. In agreement with this idea, SL-deficient plants were less sensitive to this stress. Based on the results, we propose that SLs may act as early modulators of plant responses to P starvation., Consejo Superior de Investigaciones Científicas, Grant/Award Number: 201640I040; European Regional Development Fund, Grant/Award Numbers: AGL2017‐88‐083‐R, RTI2018‐094350‐B‐C31; Generalitat Valenciana, Grant/Award Number: CDEIGENT/2018/015; Ministerio de Ciencia, Innovación y Universidades, Grant/Award Numbers: AGL2017‐88‐083‐R, RTI2018‐094350‐B‐C31, FJCI‐2015‐23575; National Network of Carotenoids, Grant/Award Number: BIO2017‐90877‐REDT

The work described here follows on from a previous study focused on the influence of the genotype and harvest time on the sesquiterpene lactone (STL) profile of Cynara cardunculus L. leaf extracts. The aim of this study was to investigate the effect that 60% plant shading in cultivated cardoon (C. cardunculus var. altilis) leaf extracts harvested in winter and spring had on the composition of STLs and the phytotoxicity. The phytotoxicity of leaf extracts was evaluated by assessing wheat coleoptile elongation along with seed germination and the root and shoot length of the weeds Amaranthus retroflexus L. and Portulaca oleracea L. Shading increased the production of STLs in spring, and this effect correlated positively with the phytotoxic activity. The induction of shading can therefore be used to modulate STL concentrations and their phytotoxic potential in cultivated cardoon leaves for industrial applications.

Stigmasterol, bergapten, and α-tomatine were isolated from tomato roots. The preliminary phytotoxic activities of stigmasterol and α-tomatine were evaluated in a wheat-coleoptile bioassay, and α-tomatine was more active than stigmasterol. To confirm its phytotoxic activity, α-tomatine was tested on Lactuca sativa and two weeds ( Lolium perenne and Echinochloa crus-galli), and it was active in all cases. The stimulatory activities of α-tomatine and stigmasterol on parasitic-plant germination were also evaluated, and α-tomatine was found to be active on Phelipanche ramosa, a parasitic plant of tomato. α-Tomatine was identified in root exudates by LC-MS/MS. This confirms that α-tomatine is exuded by roots into the environment, where it could act as both an allelochemical and a stimulator of P. ramosa, a parasitic plant of tomato.

Isohexenylnaphthazarins are commonly found in the root periderm of several Boraginaceous plants and are known for their broad range of biological activities. The work described herein concerns the biological activity of compounds from the roots of Echium plantagineum L. and Echium gaditanum Boiss (Boraginaceae) collected from field sites in southern Spain and Australia. Bioactivity was assessed using etiolated wheat coleoptile bioassay and in vitro growth inhibitory activity in HeLa and IGROV-1 cells. The quantification of four isohexenylnaphthazarins (shikonin/alkannin, deoxyshikonin/deoxyalkannin, acetylshikonin/acetylalkannin and dimethylacrylshikonin/dimethylacrylalkannin) was performed by LC-MS/MS using juglone as internal standard. Correlation coefficient values for the activities and concentrations of these four analytes were in the linear range and were greater than 0.99. Acetylshikonin/acetylalkannin and dimethylacrylshikonin/dimethylacrylalkannin were present in the highest concentrations in extracts of both species. The results reveal that greatest overall inhibition was observed in both bioassays with E. gaditanum extracts. Strong correlations between time of collection, sampling location and bioactivity were identified.

Strigolactones (SLs) are a family of natural products produced by the plants as shoot branching factors and responsible for the induction of hyphal branching in arbuscular mycorrhizal (AM) fungi. They have been also used by parasitic plant seeds as stimulators of their germination as a strategy to ensure the presence of a host in the environment. For all these bioactivities, SLs have kept the attention of the researchers in the last years, increasing the number of published papers, and have opened new areas of research in the multiple roles that they play in the rhizosphere and as plant hormones. However, the low amount of them produced by plants and their rapid degradability make it crucial to develop fast analytical methods with very low limits of quantification. Herein, it is described a protocol for the development of an LC-MS/MS method for the quantification of SLs, using GR24 as IS, in roots exudates and extracts.

Strigolactones (SLs) are a family of natural products produced by the plants as shoot branching factors and responsible for the induction of hyphal branching in arbuscular mycorrhizal (AM) fungi. They have been also used by parasitic plant seeds as stimulators of their germination as a strategy to ensure the presence of a host in the environment. For all these bioactivities, SLs have kept the attention of the researchers in the last years, increasing the number of published papers, and have opened new areas of research in the multiple roles that they play in the rhizosphere and as plant hormones. However, the low amount of them produced by plants and their rapid degradability make it crucial to develop fast analytical methods with very low limits of quantification. Herein, it is described a protocol for the development of an LC-MS/MS method for the quantification of SLs, using GR24 as IS, in roots exudates and extracts.

It has been hypothesized that the α-methylene-γ-lactone moiety of sesquiterpene lactones is a key unit for their bioactivity. As a consequence, modifications of these compounds have been focused on this fragment. In the work reported here, two sesquiterpene lactones, namely, dehydrocostuslactone and β-cyclocostunolide, a eudesmanolide obtained by controlled cyclization of costunolide, were chosen for modification by Michael addition at C-13. On applying this reaction to both compounds, it was possible to introduce the functional groups alkoxy, amino, carbamoyl, hydroxy, and thiol to give products in good to high yields, depending on the base and solvent employed. In particular, the introduction of a thiol group at C-13 in both compounds was achieved with outstanding yields (90%) and this is unprecedented for these sesquiterpene lactones. The bioactivities of the products were evaluated on etiolated wheat coleoptile elongation and germination of seeds of parasitic weeds, with significant activity observed on

A bio-guided study of leaf extracts allowed the isolation of two new macrobicyclic hydrolysable tannins, namely merianin A (1) and merianin B (2), and oct-1-en-3-yl &beta, xylopyranosyl-(1&rdquo, 6&rsquo, )-&beta, glucopyranoside (3) from Meriania hernandoi, in addition to 11 known compounds reported for the first time in the Meriania genus. The structures were elucidated by spectroscopic analyses including one- and two-dimensional NMR techniques and mass spectrometry. The bioactivities of the compounds were determined by measuring the DPPH radical scavenging activity and by carrying out antioxidant power assays (FRAP), etiolated wheat coleoptile assays and phytotoxicity assays on the standard target species Lycopersicum esculentum W. (tomato). Compounds 1 and 2 exhibited the best free radical scavenging activities, with FRS50 values of 2.0 and 1.9 &micro, M, respectively.

The excessive and inappropriate application of herbicides has caused environmental pollution. The use of allelochemicals as bioherbicides could provide a solution to this problem. The allelopathic activity of Cynara cardunculus L. has been studied previously, and sesquiterpene lactones (STLs) were identified as the most relevant allelochemicals. The goal of the study reported here was to investigate the effect of six genotypes and three harvest times on the qualitative and quantitative composition of STLs in C. cardunculus leaves through a new ultra-high-performance liquid chromatography-tandem mass spectrometry analysis method and, thus, the effect on phytotoxicity. Overall, wild cardoon contained the highest levels of STLs of the three botanical varieties studied. Nevertheless, climatic conditions had a marked influence on the presence of STLs among the six genotypes, which was higher in the April harvest. Cynaropicrin was the most abundant STL detected. A close relationship was found between the STL profiles and the allelopathic activity, expressed as inhibition of wheat coleoptile elongation. The data provide a new and important contribution to our understanding of C. cardunculus allelopathy.

[Context]: SDHB mutations are found in an increasing number of neoplasms, most notably in paragangliomas and pheochromocytomas (PPGLs). SDHB-PPGLs are slow-growing tumors, but ∼50% of them may develop metastasis. The molecular basis of metastasis in these tumors is a long-standing and unresolved problem. Thus, a better understanding of the biology of metastasis is needed. [Objective]: This study aimed to identify gene methylation changes relevant for metastatic SDHB-PPGLs. DESIGN: We performed genome-wide profiling of DNA methylation in diverse clinical and genetic PPGL subtypes, and validated protocadherin γ-C3 (PCDHGC3) gene promoter methylation in metastatic SDHB-PPGLs. [Results]: We define an epigenetic landscape specific for metastatic SDHB-PPGLs. DNA methylation levels were found significantly higher in metastatic SDHB-PPGLs than in SDHB-PPGLs without metastases. One such change included long-range de novo methylation of the PCDHA, PCDHB, and PCDHG gene clusters. High levels of PCDHGC3 promoter methylation were validated in primary metastatic SDHB-PPGLs, it was found amplified in the corresponding metastases, and it was significantly correlated with PCDHGC3 reduced expression. Interestingly, this epigenetic alteration could be detected in primary tumors that developed metastasis several years later. We also show that PCDHGC3 down regulation engages metastasis-initiating capabilities by promoting cell proliferation, migration, and invasion. [Conclusions]: Our data provide a map of the DNA methylome episignature specific to an SDHB-mutated cancer and establish PCDHGC3 as a putative suppressor gene and a potential biomarker to identify patients with SDHB-mutated cancer at high risk of metastasis who might benefit from future targeted therapies., This work was supported by the Spanish Group of Neuroendocrine Tumors (GETNE), Fundación para el Fomento en Asturias de la Investigación Científica Aplicada y la Tecnología (GRUPIN14-003), Instituto de Salud Carlos III (PI17/01901), and by European Regional Development funds (FEDER, CIBERONC).

Cultivated cardoon [Cynara cardunculus L. var. altilis (DC)] has been found to manifest phytotoxic activity on weeds and standard target species. The sesquiterpene lactones cynaripicrin, groshemin and aguerin B, as well as chlorogenic acid, luteolin and apigenin derivatives, have been indicated as the phytotoxic compounds. However, different extraction methodologies have been carried out in previous studies, resulting in different extract yields and biological activities. This work aimed to select the most efficient extraction method for the analysis of cultivated cardoon phytotoxic compounds and to broad the spectrum of its allelochemicals. Methanol, ethanol, ethyl acetate and water were used as extracting solvents and tested on wheat coleoptile bioassay. All the extracts had inhibitory effects (more than 50%), and the ethyl acetate extract was the most active (close to 100%). Extracts with the highest allelopathic potential were tested on germination rate, root length, and shoot length of six weed species (Amaranthus retroflexus L., Portulaca oleracea L., Stellaria media L., Anagallis arvensis (L.) Vil., Echinochloa crus-galli L. and Lolium perenne L.). Root length was the most affected parameter, and ethanolic and ethyl acetate extracts were the most actives. Nevertheless, as the ethyl acetate extract was previously isolated and with the aim to increase the knowledge of the allelochemicals present in the extracts of C. cardunculus, the aqueous extract was fractioned by using liquid-liquid partitions, column chromatography and HPLC analysis. Four sesquiterpene lactones (cynaropicrin, cynaratriol, desacylcynaropicrin and 11,13-dihydro-desacylcynaropicrin) and a lignan (pinoresinol) were isolated from the ethyl acetate fraction of the aqueous extract, and three of them are described in cultivated cardoon for the first time. Their general phytotoxicity was evaluated using the wheat coleoptile bioassay. Four of them evidenced allelopathic effects, with cynaropicrin, desacylcynaropicrin and pinoresinol showed the highest activity, inhibiting the wheat coleoptile by 93, 96 and 83% at 10–3 M.

Introduction: Strigolactones (SLs) are the most representative germination stimulants for seeds of root parasitic plants, and they show activity even at concentrations below 10 M. The low amounts of stimulants produced by the host and their rapid degradability make it crucial to develop analytical methods with very low limits of quantification. Objective: To develop a sensitive and validated analytical method for the simultaneous quantification of seven SLs [7-oxoorobanchyl acetate (1), solanacol (2), orobanchol (4), strigol (5), fabacyl acetate (6), orobanchyl acetate (7), and 5-deoxystrigol (8)]. Methods: SLs were analysed using ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS), with (±)-GR24 (3) employed as internal standard (IS). Validation was based on selectivity, linearity, precision of the peak areas (repeatability and intermediate precision), detection and quantification limits, and stability. Results: A simple, rapid and reliable UHPLC-MS/MS method has been validated for the routine analysis of seven SLs and has been successfully applied to quantify them in exudates and extracts from tomato roots (Solanum lycopersicum). The limits of quantifications range from 0.05 μg/L for 5-deoxystrigol to 0.96 μg/L for solanacol. Conclusion: The method provides a useful tool for research in all the fields related to SLs, both for studies related to their function as hormones, and signalling molecules in the rhizosphere, without sample preparation required for extracts and root exudates in less than 11 minutes., The authors thank Professor Miguel Palma from the University of Cadiz for his comments and help with the manuscript. Ministerio de Economía, Industria y Competitividad (MINEICO) of Spain AGL2017‐88083‐R, AGL2015‐64990‐C2‐1‐R and AGL2013‐42238‐R.

Crocus sativus stigmas are the main source of crocins, which are glucosylated apocarotenoids derived from zeaxanthin cleavage that give saffron its red color. Phytoene synthase (PSY) mediates the first committed step in carotenoid biosynthesis in plants. Four PSY genes encoding functional enzymes were isolated from saffron. All the proteins were localized in plastids, but the expression patterns of each gene, CsPSY1a, CsPSY1b, CsPSY2, and CsPSY3, in different saffron tissues and during the development of the stigma showed different tissue specialization. The CsPSY2 transcript was primarily detected in the stigmas where it activates and stimulates the accumulation of crocins, while its expression was very low in other tissues. In contrast, CsPSY1a and CsPSY1b were mainly expressed in the leaves, but only CsPSY1b showed stresslight regulation. Interestingly, CsPSY1b showed differential expression of two alternative splice variants, which differ in the intron retention at their 50 UTRs, resulting in a reduction in their expression levels. In addition, the CsPSY1a and CsPSY1b transcripts, together with the CsPSY3 transcript, were induced in roots under different stress conditions. The CsPSY3 expression was high in the root tip, and its expression was associated with mycorrhizal colonization and strigolactone production. CsPSY3 formed a separate branch to the stress-specific Poaceae homologs but was closely related to the dicot PSY3 enzymes.

The work described herein is a continuation of a previous study centered on the bioprospect of cardoon (Cynara cardunculus) leaf extracts through the isolation of secondary metabolites with phytotoxic activity. Chromatographic fractionations of the ethyl acetate extract and spectroscopic analysis showed that the majority of the components were sesquiterpene lactones. Of these compounds, aguerin B, grosheimin, and cynaropicrin were very active on etiolated wheat coleoptile, standard target species, and weed growth. The joint action of binary mixtures of these three active sesquiterpene lactones and one nonactive compound (11,13-dihydroxy-8-desoxygrosheimin) was studied. The activities of fixed-ratio mixtures were assessed on wheat coleoptile. The results can be interpreted with respect to a reference model by considering dose−response analyses and isobolograms with linear regression analyses. A total of 17 binary mixtures at different levels of inhibition (ED25, ED50, and ED75) were studied, and predominantly they responded additively (25). Deviations from additivity included seven synergistic responses and two antagonistic responses. The joint action of major sesquiterpene lactones isolated from C. cardunculus can explain the activities observed in extracts and fractions. The results reported here reiterate the utility of the wheat coleoptile bioassay as a quick tool to detect potential synergistic effects in binary mixtures.

Decachaeta , Salvia and Podachaenium genera are known for their wide variety of biological activities. Synthetic herbicides have caused a variety of environmental and resistance problems. Natural products represent an important alternative to combat such issues. Sesquiterpene lactones and diterpenes are families of bioactive natural products for which a range of activities have been described. The bioactivities of nine sesquiterpene lactones, eight heliangolides, one guaianolide and twenty two diterpenes isolated from species of the Decachaeta , Salvia and Podachaenium genera were tested by applying a methodical procedure that involves assays of compounds on etiolated wheat coleoptiles ( Triticum aestivum ), Standard Target Species (STS) and two important weeds (barnyardgrass and brachiaria). The results clearly show that all of the sesquiterpene lactones studied were active on coleoptiles. In addition, six lactones were phytotoxic on both STS and weeds, meaning that these compounds could be used in the development of natural herbicide models.

Resumen Introduccion Los cordomas de clivus son neoplasias benignas con una alta tasa de recurrencia y mortalidad. La dificultad para conseguir una reseccion total y su naturaleza infiltrativa les confieren esta agresividad. Material y metodo Se presenta una serie retrospectiva de 8 casos tratados quirurgicamente en nuestro servicio desde 1993 hasta 2006. Resultados Los 8 pacientes fueron sometidos a un total de 14 procedimientos quirurgicos, de los que 6 fueron abordajes anteriores (5 transmandibulares), 2 subtemporales-preauriculares, 2 extremolateral transcondileos y 2 transcocleares. En 7 pacientes, la intencion fue curativa. En 2 casos fue preciso realizar la cirugia de forma secuencial, en dos tiempos. Se consiguio la reseccion total en el 58% de los procedimientos. El seguimiento medio fue de 40 meses. Dos pacientes fallecieron como consecuencia de recidiva local, un paciente fallecio durante el postoperatorio y otro paciente fallecio por causas no relacionadas con el tumor. Discusion La baja incidencia de los cordomas de clivus dificulta la elaboracion de estudios randomizados acerca de su manejo. El tratamiento de eleccion es la cirugia, complementado con radioterapia en casos seleccionados. Preferimos emplear el abordaje transmandibular, combinandolo con extremolateral transcondileo, en el caso de afectacion condilar. Para extensiones laterales, optamos por el abordaje subtemporal-preauricular o vias transpetrosas. Las nuevas modalidades radioterapicas permiten el tratamiento eficaz de los remanentes tumorales. Conclusiones Los abordajes extradurales implican regiones anatomicas familiares para el otorrinolaringologo. Es imprescindible conocer las limitaciones de cada abordaje, a fin de evitar morbilidades innecesarias y resecciones incompletas.

Jugular fossa tumors are uncommon diseases. During the surgery and due to the interposition of the facial nerve in the tumor approach, the facial nerve must be elevated from the fallopian canal and placed permanently into an anterior position. Although this maneuver provides a wide exposure, most of the patients suffer a long-term total or partial facial palsy. The purpose of this article is to check whether the infratemporal fossa approach without transposition of the facial nerve is equivalent to the approach with rerouting of the facial nerve regarding postsurgical morbidity. The clinical records of 52 patients who underwent an infratemporal fossa approach were reviewed in which 34 patients were segregated into two comparable groups regarding the presence or absence of transposition of the facial nerve. There were 19 women and 15 males. The majority of the patients (73%) had jugular paragangliomas. The mean follow-up of the full series was 66 months. It was statistically significant that the worst facial nerve function at hospital discharge was in the patients who underwent facial nerve transposition (p = 0.001). Equally the facial nerve function in the no-rerouting group 1 year after the surgery was significantly much better than in the rerouting group (p = 0.003). Regarding to survival, recurrence or complications no significant differences were observed between both groups. Our study suggests that most of cases avoiding facial nerve transposition allow significant better functional results thereof without affecting other parameters such as recurrence, complications or survival.

Objective Successful resection of complex tumors involving the skull base (SB) depends on the ability to reconstruct the resulting defects. The objective of this study was to assess the outcomes of patients undergoing reconstruction after resection of SB tumors with free flaps. Methods From 1995 to 2010 a retrospective review of cases was undertaken. Demographics, histology, surgical management, complications, locoregional control, and survival were analyzed. Results We performed 62 flaps in 57 patients. There was a preponderance of sinonasal malignancies (45%), and most lesions involved the anterior SB (81%). A total of 94% of patients underwent radiotherapy. Reconstruction was undertaken mainly with anterolateral thigh (37%) or radial forearm (34%) flaps. Complications occurred in 17% of patients, and the flap's success rate was 94%. Conclusion Free flaps are versatile and highly reliable for reconstructing defects resulting from resections of the SB. They should be considered for SB reconstruction of large three-dimensional defects as well as defects involving an irradiated field. Successful reconstruction of the SB can be performed using a small number of highly dependable flaps.

Introduction Clival chordomas are benign neoplastic tumours displaying high morbidity and mortality rates. The difficulties involved in obtaining a total resection and its infiltrative nature explain this aggressiveness. Materials and method We present a retrospective clinical series of 8 cases of clival chordomas treated surgically at our department from 1993 to 2006. Results All 8 patients underwent a total of 14 surgical procedures, 6 of which were anterior approaches (5 transmandibular), 2 subtemporal-preauricular, 2 from the extreme lateral transcondylar and 2 transcochlear. In 7 patients, the surgery was performed with curative intent. In 2 cases, it was necessary to perform the surgery sequentially, in two steps. Total resection was achieved in 58% of patients. Average follow up was 40 months. Two patients died due to local recurrence, one patient died in the postoperative period and another died due to causes not related with the tumour. Discussion The low incidence of clival chordomas makes it difficult to carry out random clinical studies of its management. The treatment of choice is surgery, supplemented by radiotherapy in selected cases. We prefer the transmandibular approach, combined with extreme lateral transcondylar approach when the occipital condyle is infiltrated. For lateral extensions, we use the subtemporal-preauricular or transpetrosal approaches. New radiotherapy modalities provide an effective treatment of tumour residues. Conclusions Extradural approaches imply anatomical regions familiar for otolaryngologists. Specific knowledge about the limitations of each approach is essential to avoid unnecessary morbidity and incomplete resections.

In recent years, meningitis caused by methicillin-resistant S. aureus has increased. This study was undertaken to compare the clinical characteristics and prognosis of methicillin-resistant S. aureus (MRSA) postneurosurgical meningitis and methicillin-sensible S. aureus (MSSA) postneurosurgical meningitis.Twenty-five episodes of postneurosurgical meningitis due to S. aureus (13 methicillin-resistant strains) seen during a ten-year period were retrospectively reviewed.Most common underlying diseases were: intracerebral hemorrhage (50% of MRSA patients and 46% of MSSA patients) and neoplasm (53% of MRSA patients and 33% of MSSA patients). Eleven patients (6 of them with MRSA infection) had received antibiotic treatment previously. Thirteen patients were carriers of intraventricular catheters (8 with MRSA infection), 5 wore a ventriculoperitoneal shunt (4 with infections by MSSA), 5 cases had a CSF leakage (4 with infections by MRSA), and one patient with infection by MSSA wore an epidural catheter. Fifteen patients were cured (7 with MRSA infection), and 8 died due to the infection (27% with MSSA infection and 38% with MRSA infection).The prognosis of postneurosurgical meningitis by S. aureus does not depend on the presence of resistance to methicillin. Nowadays, the intravenous administration of vancomycin is the treatment of choice in MRSA meningitis.

Fundamento y objetivo En los ultimos anos se ha descrito con frecuencia creciente casos de meningitis producidas por cepas de Staphylococcus aureus resistentes a meticilina (SARM). Se estudian las caracteristicas diferenciales tanto clinicas como pronosticas de los pacientes diagnosticados de meningitis posquirurgicas debidas a SARM y las debidas a Staphylococcus aureus sensibles a meticilina (SASM). Pacientes y metodos Estudio retrospectivo, de 1992 a 2002, de 25 episodios de meningitis nosocomial posquirurgica por Staphylococcus aureus, de los que 13 fueron por SARM. Resultados Las enfermedades subyacentes mas frecuentemente diagnosticadas fueron la hemorragia cerebral (el 50% de los pacientes con SARM y el 46% de los pacientes con SASM) y las neoplasias (el 53% de los pacientes con SARM y el 33% de los pacientes con SASM). En 11 enfermos se recogia el antecedente de tratamiento antibiotico previo (6 de ellos con infeccion por SARM). Trece de los pacientes eran portadores de cateteres intraventriculares (8 con infecciones por SARM), 5 portaban una derivacion ventriculoperitoneal (4 con infecciones por SASM), otros 5 casos presentaban una fistula de liquido cefalorraquideo (4 con infecciones por SARM) y 1 paciente con infeccion por SASM tenia un cateter epidural. En 15 casos se produjo la curacion (7 con SARM), 1 enfermo de cada grupo recidivo y 8 fallecieron a consecuencia directa de la infeccion (el 27% de los pacientes con SASM y el 38% de los enfermos con SARM). Conclusiones La presencia de resistencia a la meticilina no parece empeorar el pronostico de los pacientes con meningitis posquirurgica por Staphylococcus aureus. Aunque la vancomicina permanece como tratamiento de eleccion, es posible que nuevos antibioticos de reciente aparicion cambien en el futuro el tratamiento de esta entidad.