Role of adaptive leadership in learning organizations to boost organizational innovations with change self-efficacy.

The present study investigates the direct impact of learning organizations on organizational innovations and investigates the mediating mechanism of change self-efficacy between learning organizations and organizational innovations. Furthermore, this study proposes adaptive leadership as a moderator between learning organizations, change self-efficacy, and organizational innovations. Three hundred seventy-three permanent employees from the pharmaceutical industry voluntarily participated. Data was collected using a simple random sampling technique through the temporal separation method (One-month interval between two temporal separations). SPSS v.25, AMOS v.22, and Smart-PLS were utilized to analyze reliability, validity, descriptive statistics, and correlations, and PROCESS-macro v3.4 was used for direct, indirect (mediation), and interaction (moderation) effects analysis. The study supports the hypothesized link between learning organizations and organizational innovations. In addition, change self-efficacy partially mediates the learning organizations - organizational innovations relationship. Moreover, adaptive leadership moderates the association between learning organization and organizational innovation, learning organizations and change self-efficacy, and change self-efficacy and organizational innovations relationship. The study's findings suggest that adaptive leadership is imperative not only for higher change self-efficacy of the individuals but also helps the organizations for organizational innovations with the utilization of learning organizations phenomenon. Additionally, this study highlights the importance of change self-efficacy, which plays a vital role in learning organizations for organizational innovations. Supplementary Information: The online version contains supplementary material available at 10.1007/s12144-023-04669-z.

Preparation and Phytotoxicity Evaluation of 11,13-Dehydro seco-Guaianolides.

11,13-Dehydro seco-guaianolides, a particular type of sesquiterpene lactones, were synthesized from the commercially available α-santonin (11) using a facile strategy involving a high-yielding photochemical reaction. Natural products 10 and 17 from Artemisia gorgonum were synthesized in good yields. Specifically, compound 10 was obtained in five steps with an overall yield of 17%. The sesquiterpene lactones were tested in the etiolated wheat coleoptile bioassay, and the most active compounds were assayed on standard target species. Guaianolide 13 showed the highest phytotoxic activities when compared with the known herbicide Logran.

Resistance modulatory and efflux-inhibitory activities of capsaicinoids and capsinoids.

Capsaicinoids are reported to have a bunch of promising pharmacological activities, among them antibacterial effects against various strains of bacteria. In this study the effect on efflux pumps of mycobacteria was investigated. The importance of efflux pumps, and the inhibition of these, is rising due to their involvement in antibiotic resistance development. In order to draw structure and activity relationships we tested natural and synthetical capsaicinoids as well as synthetical capsinoids. In an accumulation assay these compounds were evaluated for their ability to accumulate ethidium bromide into mycobacterial cells, a well-known substrate for efflux pumps. Capsaicin and dihydrocapsaicin, the two most abundant capsaicinoids in Capsicum species, proved to be superior efflux pump inhibitors compared to the standard verapamil. A dilution series showed dose dependency of both compounds. The compound class of less pungent capsinoids qualified for further investigation as antibacterials against Mycobacterium smegmatis.

Synthesis of bioactive speciosins G and P from Hexagonia speciosa.

The first total synthesis of speciosins P and G, previously isolated from Hexagonia speciosa, is reported. These compounds have been synthesized by Sonogashira coupling from readily available starting materials. Siccayne was also synthesized from the same starting material in two steps along with a number of other derivatives. The compounds were tested in the wheat coleoptile bioassay. The most active compound was the intermediate 18, followed by 29 and 17. The structural requirements for activity in these compounds are the presence of methoxy groups in the aromatic ring and a formyl or hydroxy group in the side chain.

On the formulation of disulfide herbicides based on aminophenoxazinones: polymeric nanoparticle formulation and cyclodextrin complexation to combat crop yield losses.

BACKGROUND: The resistance of weeds to herbicides is a significant issue in ensuring future food supply. Specific examples are Plantago lanceolata, Portulaca oleracea and Lolium rigidum, which mainly infect rice, wheat, barley and pastures, and cause high yield losses every year. In this regard, natural products and their mimics have provided new hope as a result of their different modes-of-action, activity at low concentrations and reduced pollution effects relative to conventional herbicides. However, the poor water solubility and physicochemical properties of these compounds limit their broad application. These problems can be addressed by formulation techniques, and encapsulation appears to be of great interest. RESULTS: Disulfide herbicides inspired by aminophenoxazinones have been formulated with 2-hydroxypropyl-ß-cyclodextrin (HP-ß-CD), γ-CD and polymeric nanoparticles (NPs). In silico studies were employed to identify which complexes would be generated and complex formation was confirmed by nuclear magnetic resonance spectroscopy. Solubility diagrams were generated to assess any improvement in water solubility, which was enhanced 2-13-fold. Scanning electron microscopy and energy-dispersive X-ray spectra confirmed the success of the formulation process for the nanoparticles. Formulated compounds were evaluated in an in vitro wheat coleoptile bioassay, with almost 100% elongation inhibition achieved using only water for the bioassay. Specific in vitro testing on weed phytotoxicity showed that the application of core/shell NPs is highly effective in the fight against P. lanceolata seed germination. CONCLUSIONS: The formulation of disulfide herbicides with CD complexes and NPs led to an enhancement in water solubility and bioactivity. These systems can be applied in pre-emergent mode against P. lanceolata, using only water to prepare the sample, and they showed better activity than the positive controls. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Biological Activity of Naphthoquinones Derivatives in the Search of Anticancer Lead Compounds.

Naphthoquinones are a valuable source of secondary metabolites that are well known for their dye properties since ancient times. A wide range of biological activities have been described highlighting their cytotoxic activity, gaining the attention of researchers in recent years. In addition, it is also worth mentioning that many anticancer drugs possess a naphthoquinone backbone in their structure. Considering this background, the work described herein reports the evaluation of the cytotoxicity of different acyl and alkyl derivatives from juglone and lawsone that showed the best activity results from a etiolated wheat coleoptile bioassay. This bioassay is rapid, highly sensitive to a wide spectrum of activities, and is a powerful tool for detecting biologically active natural products. A preliminary cell viability bioassay was performed on cervix carcinoma (HeLa) cells for 24 h. The most promising compounds were further tested for apoptosis on different tumoral (IGROV-1 and SK-MEL-28) and non-tumoral (HEK-293) cell lines by flow cytometry. Results reveal that derivatives from lawsone (particularly derivative 4) were more cytotoxic on tumoral than in non-tumoral cells, showing similar results to those obtained with of etoposide, which is used as a positive control for apoptotic cell death. These findings encourage further studies on the development of new anticancer drugs for more directed therapies and reduced side effects with naphthoquinone skeleton.

Determination of Caffeoylquinic Acids Content by UHPLC in Scolymus hispanicus Extracts Obtained through Ultrasound-Assisted Extraction.

Scolymus hispanicus L., also known as golden thistle, Spanish oyster thistle or, more commonly, as tagarnina is a plant that belongs to the Asteraceae family. It is collected from the wild for human consumption in Mediterranean countries. It is a relevant ingredient in Andalusian culinary culture, where the midribs of young plants are harvested for consumption. Scolymus hispanicus L. contains a wide variety of phenolic compounds such as caffeoylquinic acids (CQAs), among others. In the present work, the major phenolic compounds present in tagarnina have been identified, with 5-caffeoylquinic acid (5-CQA) and 3,5-dicaffeoylquinic acid (3,5-diCQA) being the main ones. A method based on ultrasound-assisted extraction (UAE) has been developed for the extraction of these compounds, with the percentage of methanol, sample-to-solvent ratio and the pH being the most influential factors. The developed method has been validated and employed to determine the concentration of 5-CQA and 3,5-diCQA in the midribs of Scolymus hispanicus, collected in six different places in the south of Spain. The antioxidant activity of the samples has also been determined, and a direct correlation with their caffeoylquinic compounds content has been established, showing an antioxidant effect.

Effects of Sesquiterpene Lactones on Primary Cilia Formation (Ciliogenesis).

Sesquiterpene lactones (SLs), plant-derived metabolites with broad spectra of biological effects, including anti-tumor and anti-inflammatory, hold promise for drug development. Primary cilia, organelles extending from cell surfaces, are crucial for sensing and transducing extracellular signals essential for cell differentiation and proliferation. Their life cycle is linked to the cell cycle, as cilia assemble in non-dividing cells of G0/G1 phases and disassemble before entering mitosis. Abnormalities in both primary cilia (non-motile cilia) and motile cilia structure or function are associated with developmental disorders (ciliopathies), heart disease, and cancer. However, the impact of SLs on primary cilia remains unknown. This study evaluated the effects of selected SLs (grosheimin, costunolide, and three cyclocostunolides) on primary cilia biogenesis and stability in human retinal pigment epithelial (RPE) cells. Confocal fluorescence microscopy was employed to analyze the effects on primary cilia formation (ciliogenesis), primary cilia length, and stability. The effects on cell proliferation were evaluated by flow cytometry. All SLs disrupted primary cilia formation in the early stages of ciliogenesis, irrespective of starvation conditions or cytochalasin-D treatment, with no effect on cilia length or cell cycle progression. Interestingly, grosheimin stabilized and promoted primary cilia formation under cilia homeostasis and elongation treatment conditions. Thus, SLs have potential as novel drugs for ciliopathies and tumor treatment.

Enhancing Anthocyanin Extraction from Wine Lees: A Comprehensive Ultrasound-Assisted Optimization Study.

Wine lees, an important by-product of the wine industry, pose a major environmental problem due to the enormous quantities of solid-liquid waste that are discarded annually without defined applications. In this study, the optimization of a method based on a Box-Behnken design with surface response has been carried out to obtain extracts with high anthocyanin content and potent antioxidant activity. Six variables have been considered: %EtOH, temperature, amplitude, cycle, pH, and ratio. The developed method exhibited important repeatability properties and intermediate precision, with less than 5% CV being achieved. Furthermore, these novel methods were successfully applied to diverse wine lees samples sourced from Cabernet Sauvignon and Syrah varieties (Vitis vinifera), resulting in extracts enriched with significant anthocyanin content and noteworthy antioxidant activity. Additionally, this study evaluated the influence of grape variety, fermentation type (alcoholic or malolactic), and sample treatment on anthocyanin content and antioxidant activity, providing valuable insights for further research and application in various sectors. The potential applications of these high-quality extracts extend beyond the winemaking industry, holding promise for fields like medicine, pharmaceuticals, and nutraceuticals, thus promoting a circular economy and mitigating environmental contamination.

In Silico Evaluation of Sesquiterpenes and Benzoxazinoids Phytotoxins against Mpro, RNA Replicase and Spike Protein of SARS-CoV-2 by Molecular Dynamics. Inspired by Nature.

In the work described here, a number of sesquiterpenes and benzoxazinoids from natural sources, along with their easily accessible derivatives, were evaluated against the main protease, RNA replicase and spike glycoprotein of SARS-CoV-2 by molecular docking. These natural products and their derivatives have previously shown remarkable antiviral activities. The most relevant compounds were the 4-fluoro derivatives of santamarine, reynosin and 2-amino-3H-phenoxazin-3-one in terms of the docking score. Those compounds fulfill the Lipinski's rule, so they were selected for the analysis by molecular dynamics, and the kinetic stabilities of the complexes were assessed. The addition of the 4-fluorobenzoate fragment to the natural products enhances their potential against all of the proteins tested, and the complex stability after 50 ns validates the inhibition calculated. The derivatives prepared from reynosin and 2-amino-3H-phenoxazin-3-one are able to generate more hydrogen bonds with the Mpro, thus enhancing the stability of the protein-ligand and generating a long-term complex for inhibition. The 4-fluoro derivate of santamarine and reynosin shows to be really active against the spike protein, with the RMSD site fluctuation lower than 1.5 Å. Stabilization is mainly achieved by the hydrogen-bond interactions, and the stabilization is improved by the 4-fluorobenzoate fragment being added. Those compounds tested in silico reach as candidates from natural sources to fight this virus, and the results concluded that the addition of the 4-fluorobenzoate fragment to the natural products enhances their inhibition potential against the main protease, RNA replicase and spike protein of SARS-CoV-2.

Aneugenic effects of benzoxazinones in cultured human cells.

Benzoxazinones (BAs) are natural products that are present in Gramineae and represent part of the plant defence system against pests. In recent years, sprouts of maize, wheat and rye have been used for the production of dietary supplements. We have investigated the potential genotoxic activities of a diverse range of synthetic derivatives of the most abundant natural BA, namely DIBOA (2,4-dihydroxy-1,4-benzoxazin-3-one), proposed for use as a potential herbicide. We have tested 18 synthetic BAs for potential effects in cultured HeLa cells. We found significantly higher micronucleus (MN) induction over the background level, with the solvent DMSO used as an internal control. Concentration-dependent effects were found between 1nM and 20nM for all the synthetic compounds studied. Immunostaining with an anticentromere antibody showed that >80% of MN induced gave a centromere-positive signal. Similarly, fluorescence in situ hybridization (FISH) analysis with alphoid centromere probes showed a positive hybridization signal, indicating that all compounds analyzed are aneugenic. Chemical modification of the N in the heterocyclic aromatic amine served us to suggest a relationship between the structure and the aneugenic effects of the compounds analyzed. Our findings indicate that benzoxazinoids could be potential genotoxins for human cells.

Structure-activity relationship studies on naphthoquinone analogs. The search for new herbicides based on natural products.

BACKGROUND: Allelopathy and bioassays constitute fundamental tools in the search for new herbicide templates. The work described here is a continuation of a previous study focused on the structure-activity relationships between transport phenomena and phytotoxic activity. Different modifications were made to the naphthoquinone backbone and two key factors were identified as being responsible for changes in activity: lipophilicity and the nature of the functional group. The study of other naturally occurring and semi-synthetic naphthoquinones was also proposed. RESULTS: A total of 12 5-O-acyl plumbagins and 18 analogs with unsaturated and aromatic substituents at positions 2 and 5 were synthesized. These compounds were evaluated in the wheat coleoptile bioassay and against Standard Target Species (STS) and three weeds, namely Echinochloa crus-galli L., Lolium rigidum Gaud. and Lolium perenne L. A strong structure-function relationship was observed for the different naphthoquinones and root and shoot length were the parameters that were most affected. CONCLUSION: Strong inhibitory effects were observed for the isomeric forms 23 and 33 and the derivatives with a free hydroxyl group, i.e. 24 and 30, gave values higher than 70% inhibition for root length in barnyardgrass and perennial ryegrass. These results highlight the potential of these compounds as models in the development of herbicides based on natural products. © 2019 Society of Chemical Industry.

Influence of lipophilicity in O-acyl and O-alkyl derivatives of juglone and lawsone: a structure-activity relationship study in the search for natural herbicide models.

BACKGROUND: Naphthoquinones are known for their broad range of biological activities. Given the increasing demands of consumers in relation to food quality and growing concerns about the impact of synthetic herbicides, it is necessary to search for new agrochemicals. Natural products and allelopathy provide new alternatives for the development of pesticides with lower toxicity and greater environmental compatibility. RESULTS: A structure-activity relationship to evaluate the effect of bioavailability was performed. A total of 44 O-acyl and O-alkyl derivatives of juglone and lawsone with different linear chain lengths were prepared. These compounds were tested on etiolated wheat coleoptiles, standard target species (STS) and four weeds, Echinochloa crus-galli L., Lolium rigidum Gaud., Lolium perenne L. and Avena fatua L. The results showed a strong influence of lipophilicity and, in most cases, the data fitted a logP-dependent quadratic mathematical model. CONCLUSION: The effects produced were mostly stunting and necrosis caused by growth inhibition. The potential structure and activity behaviour is described. © 2017 Society of Chemical Industry.

Qualitative Study on the Production of the Allelochemicals Benzoxazinones by Inducing Polyploidy in Gramineae with Colchicine.

The possibility of inducing polyploidy in grasses by treatment with colchicine and its effect on the production and root exudate content of 2,4-dihydroxy-7-methoxy-2 H-1,4-benzoxazin-3-one (DIMBOA) and 2,4-dihydroxy-2 H-benzoxazin-3-one (DIBOA) was studied in wheat, corn, and rye. Caryopses treated with colchicine at concentrations in the range of 0.1-10 mg/mL for 8 and 48 h and with inoculation of the growth medium are markedly affected in terms of both the distribution and concentration levels of allelochemicals in plants. A greater accumulation was observed in the root with respect to the stem, and this increased with an increasing concentration of colchicine and with treatment time. Analysis of the compounds released by root exudates showed that treatment with colchicine at a concentration higher than 1 mg/mL caused a significant increase in the concentrations of allelochemicals measured in the growth medium. It is proposed that treatment with colchicine of seedling caryopses mixoploids plant populations and that the overall effect is an increase in the levels of allelochemicals released. The ecological implications of this behavior are discussed along with the impact of plant-plant interactions (allelopathy).

Chemical evidence for the effect of Urochloa ruziziensis on glyphosate-resistant soybeans.

BACKGROUND: Soybean (Glycine max) is an important oleaginous legume that has been cultivated in new areas in Brazil, including pastures. Problems of reduced production yields have been reported by soybean growers when the crop is sown immediately after desiccation of pastures of Urochloa spp. using glyphosate. The objective of this work was to extract, isolate and identify the major chemicals from U. ruziziensis that have phytotoxic activity and to evaluate the possible relation between this effect and reduced soybean yield. RESULTS: U. ruziziensis plants at the flowering stage were desiccated using glyphosate at 1.44 kg ha-1 . The plants were collected between five and ten days after treatment. Extracts of dried and ground shoots were obtained by sequential extraction with hexane, dichloromethane and methanol. The results of wheat coleoptile bioassays indicated that the methanol extract was more inhibitory than the dichloromethane extract regardless of glyphosate application. CONCLUSION: Protodioscin, a steroidal saponin, was isolated from the extract as the major component and the activities of this compound were in good agreement with those found for the extract. The release of this compound into the soil is a plausible explanation for the decrease in production observed in transgenic soybean crop after desiccation of U. ruziziensis. © 2017 Society of Chemical Industry.

Bioactive steroids from Oryza sativa L.

Rice is one of the most interesting crops in the world from both the social and the economic point of views. The monoculture practices along with the heavy use of herbicides are characteristic of modern agriculture and are inducing the appearance of tolerant and/or herbicide resistant weed biotypes. This is the case the world's main weed of rice barnyardgrass (Echinochloa crus-galli). Alternative strategies for weed suppression consist of the use of chemicals from rice due to necessity of obtaining new herbicides with new modes of action that could prevent resistance phenomena. In order to carry out a study that guides to the isolation of the most active compounds from rice, different extracts were achieved, and their activities evaluated. So, all the plant material was divided into three parts: fresh plant, dried plant, and fresh plant from Pluviotron. The aerial part was separated from roots in all cases and extracted in water, in organic solvents as well as with the Pluviotron device. The activity of the 12 extracts obtained was evaluated using a generalist bioassay, wheat etiolated coleoptiles bioassay, and a phytotoxic bioassay on barnyardgrass as target species. The bioactive extracts were fractionated and 15 compounds were isolated and identified by spectroscopic methods. Eight of these compounds were isolated for the first time in Oryza sativa. The most phytotoxic compounds on E. crus-galli were ergosterol peroxide and 7-oxo-stigmasterol. In the case of ergosterol peroxide the activity was higher than the commercial herbicide Logran. This is the first report of potential allelopathic activity of steroids on weeds based on their phytotoxicity.

New herbicide models from benzoxazinones: aromatic ring functionalization effects.

The utility of benzoxazinones and some of their synthetic derivatives in the search for new leads for herbicide model development has been widely discussed. As the benzoxazinone skeleton contains three different potential areas for functionalization (C-2, N-4, and aromatic protons H-5, H-6, H-7, and H-8), and the first two have already been optimized, the main objective of this work was the substitution of aromatic protons for different substituent types and the study of the effects of the prepared chemicals on selected standard target species (STS) and weeds. Thus, different combinations of aromatic substituents, including methoxy, methoxycarbonyl, fluorine, chlorine, and trifluoromethyl, were introduced at different positions. Phytotoxicity results were successfully correlated with steric and electronic molecular parameters, the resulting molecular volume (V) and dipole moment (mu) being the most influential ones. Halogenations at C-6 and fluorination at C-7 were the most successful modifications. Compounds 6-fluoro-(2H)-1,4-benzoxazin-3(4H)-one (6F-D-DIBOA), 7-fluoro-(2H)-1,4-benzoxazin-3(4H)-one (7F-D-DIBOA), and 6-chloro-(2H)-1,4-benzoxazin-3(4H)-one (6Cl-D-DIBOA) had the highest phytotoxic activities. The dose-response profiles on wheat and two of its most common weeds (Lolium rigidum Gaud. and Avena fatua L.) were compared by means of a proposed selectivity index, which displayed 7F-D-DIBOA as the most selective of the tested benzoxazinones.

Structure-activity relationship studies of benzoxazinones and related compounds. Phytotoxicity on Echinochloa crus-galli (L.) P. Beauv.

Echinochloa crus-galli (E. crus-galli; barnyardgrass) is a weed widely distributed. It constitutes a serious weed problem in 42 countries and has been found in at least 27 more. It is the world's main weed of rice affecting up to 36 crops worldwide. Several biotypes of this plant, with resistance to herbicides with different modes of action have evolved. In our ongoing studies regarding the potential application of benzoxazinones and their soil degradation products for weed control, a complete structure-activity relationships (SARs) study was made by using barnyardgrass as the target plant. Compounds used in this study were previously tested on a wide variety of standard target species (STS), and they include natural allelochemicals 2-O-beta-D-glucopyranosyl-4-hydroxy-(2H)-1,4-benzoxazin-3(4H)-one (DIBOA-Glc), 2,4-dihydroxy-7-methoxy-(2H)-1,4-benzoxazin-3(4H)-one (DIMBOA), and 2,4-dihydroxy-(2H)-1,4-benzoxazin-3(4H)-one (DIBOA), together with some degradation derivatives found in wheat crop soil and some synthetic analogues. Their phytotoxicity on E. crus-galli is discussed and compared with the results obtained from previous screening. This work constitutes the next step in the search for natural herbicide models based on benzoxazinones and their degradation products. The most active compounds were the degradation product 2-aminophenol (APH) and the synthetic analogue 4-hydroxy-(2H)-1,4-benzoxazin-3(4H)-one (D-DIBOA). Their activities confirm the direction proposed in our previous SAR study, which establishes D-DIBOA to be the best lead for natural herbicide model development with benzoxazinone structure.

Structure-activity relationship studies of the phytotoxic properties of the diterpenic moiety of breviones.

BACKGROUND: Brevianes are a family of bioactive meroterpenoids originally described in fungi of the family Penicillium. These compounds have attracted a great deal of interest not only because of their unusual skeleton, suggesting a mixed mevalonate and polyketide biogenetic pathway, and their unusual oxa-spiro ring fused to an α-pyrone, but also because of the bioactivities shown by many members of this family. RESULTS: During the course of a project aimed at the total synthesis of natural breviones A to E, the authors were able to synthesise the diterpenic moiety of brevianes and abeo-brevianes. As a result, a collection of 25 compounds were synthesised and tested for bioactivity by two different bioassays. The bioassays used were etiolated wheat coleoptiles (Triticum aestivum) and seedlings in petri dishes. The plant species tested in the seedling bioassay were the commercial dicots lettuce and cress and the monocot weeds Echinochloa crus-galli and Lolium rigidum. CONCLUSIONS: The results clearly show that expanded phenanthrene-like compounds corresponding to the diterpenic moiety of abeo-brevianes are more selective towards E. crus-galli in comparison with L. rigidum. Such selectivity can reach up to one order of magnitude (200-fold) and makes some of the compounds good candidates as leads for the development of more specific herbicides.

Evidence for an allelopathic interaction between rye and wild oats.

Allelopathy is a biological phenomenon in which an organism produces one or more biochemicals that influence the growth, survival, and reproduction of other organisms. Allelopathy has been the subject of a great deal of research in chemical ecology since the 1930s. The characterization of the factors that influence this phenomenon has barely been explored, mainly due to the complexity of this area. The main aim of the research carried out to date has been to shed light on the importance of these interactions in agroecosystems, especially in relation to the interactions between crops and weeds. Herein we report the characterization of a complete allelochemical pathway involving benzoxazinones, which are known to participate in allelopathic plant defense interactions of several plants of high agronomic interest. The production of the defense chemicals by a donor plant (crop), the route and transformations of the chemicals released into the environment, and the uptake and phytotoxic effects on a target plant (weed) were all monitored. The results of this study, which is the first of its kind, allowed a complete dynamic characterization of the allelopathic phenomenon for benzoxazinones.