Academic literature on the topic 'Chalcones'
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Journal articles on the topic "Chalcones"
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Olender, Dorota, Anna Pawełczyk, Anna Leśków, Katarzyna Sowa-Kasprzak, Lucjusz Zaprutko, and Dorota Diakowska. "Synthesis of bis-Chalcones Based on Green Chemistry Strategies and Their Cytotoxicity Toward Human MeWo and A375 Melanoma Cell Lines." Molecules 29, no. 21 (October 31, 2024): 5171. http://dx.doi.org/10.3390/molecules29215171.
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Chalcone is an aromatic ketone that forms the central core of many important biological compounds. Chalcone derivatives show various biological activities, especially anti-inflammatory, antibacterial, antioxidant, and anticancer activities, and also inhibit melanoma cell growth. In this study, we synthesized chalcone compounds with bis-chalcone’s chemical structure under microwave (MW) and microwave–ultrasound (MW-US) conditions and compared them to chalcones produced using the classical synthesis method. All bis-chalcones were synthesized with terephthalaldehyde and an appropriate aromatic ketone as substrates in Claisen–Schmidt condensation. All the obtained compounds were tested regarding their roles as potential anticancer agents. The cytotoxic effect of the bis-chalcones against human MeWo and A375 melanoma cell lines was investigated through colorimetric MTT and SRB assays. The data were analyzed statistically. In the case of the synthesis of bis-chalcones, it was determined that the use of green conditions supported by the MW or MW-US factors led to an increase in the yield of the final products and a reduction in the reaction time compared to the classic method. The biological results showed the high cytotoxic effect of bis-chalcones. The present results show the compounds’ high antiproliferative and cytotoxic potential, especially for the two selected bis-chalcone derivatives (3b and 3c), in particular, at concentrations of 50 μM–200 μM at 24, 48 h, and 72 h of incubation. The use of MW and US for the synthesis of bis-chalcones significantly improved the process compared to the classical method. The derivatives containing two hydroxy and two methoxy groups were the most effective against the tested cancer cells.
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Georgiou, Nikitas, Andromachi Tzani, Kyriaki Vavougyiou, Christos Papadopoulos, Nikolaos Eleftheriadis, Primož Šket, Demeter Tzeli, Tuomas Niemi-Aro, Anastasia Detsi, and Thomas Mavromoustakos. "Synthesis of Anti-Inflammatory Drugs’ Chalcone Derivatives and a Study of Their Conformational Properties Through a Combination of Nuclear Magnetic Resonance Spectroscopy and Molecular Modeling." Pharmaceuticals 18, no. 1 (January 13, 2025): 88. https://doi.org/10.3390/ph18010088.
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Background: In this study, two chalcone analogs were synthesized through in silico and experimental methods, and their potential to inhibit the lipoxygenase enzyme, which plays a role in the inflammation pathway, was assessed. Specifically, this study is a continuation of previous research in which chalcone derivatives were synthesized and characterized. Objectives/Methods: In the current work, we present the re-synthesis of two chalcones, with a focus on their docking studies, NMR analysis, and dynamic simulations. The structure of each chalcone was elucidated through a combination of Nuclear Magnetic Resonance (NMR) and Density Functional Theory (DFT). The substituent effect on the absorption spectrum of the two chalcone derivatives was studied. Results: A “LOX–chalcone” complex, predicted by docking studies, was further examined using molecular dynamics (MD) simulations to evaluate the stability of the complex. After fully characterizing the “LOX–chalcone” complexes in silico, the atomic details of each chalcone’s interaction with LOX-1 and 5-LOX were revealed through Saturation Transfer Difference (STD) NMR (Nuclear Magnetic Resonance). Finally, their selectivity profile was investigated against human 15-LOX-1 and general Lipoxidase activity. Conclusions: The in silico methods suggest that chalcones could be promising lead compounds for drug designs targeting the LOX enzyme.
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Rudrapal, Mithun, Johra Khan, Abdul Aziz Bin Dukhyil, Randa Mohammed Ibrahim Ismail Alarousy, Emmanuel Ifeanyi Attah, Tripti Sharma, Shubham Jagdish Khairnar, and Atul Rupchand Bendale. "Chalcone Scaffolds, Bioprecursors of Flavonoids: Chemistry, Bioactivities, and Pharmacokinetics." Molecules 26, no. 23 (November 26, 2021): 7177. http://dx.doi.org/10.3390/molecules26237177.
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Chalcones are secondary metabolites belonging to the flavonoid (C6-C3-C6 system) family that are ubiquitous in edible and medicinal plants, and they are bioprecursors of plant flavonoids. Chalcones and their natural derivatives are important intermediates of the flavonoid biosynthetic pathway. Plants containing chalcones have been used in traditional medicines since antiquity. Chalcones are basically α,β-unsaturated ketones that exert great diversity in pharmacological activities such as antioxidant, anticancer, antimicrobial, antiviral, antitubercular, antiplasmodial, antileishmanial, immunosuppressive, anti-inflammatory, and so on. This review provides an insight into the chemistry, biosynthesis, and occurrence of chalcones from natural sources, particularly dietary and medicinal plants. Furthermore, the pharmacological, pharmacokinetics, and toxicological aspects of naturally occurring chalcone derivatives are also discussed herein. In view of having tremendous pharmacological potential, chalcone scaffolds/chalcone derivatives and bioflavonoids after subtle chemical modification could serve as a reliable platform for natural products-based drug discovery toward promising drug lead molecules/drug candidates.
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Chen, Jie, Chen-Fu Liu, and Guo-Wu Rao. "Progress in the Synthesis, Angiogenesis Activity and Mechanism of Chalcone Derivatives." Mini-Reviews in Organic Chemistry 17, no. 7 (October 9, 2020): 814–27. http://dx.doi.org/10.2174/1570193x17666191223161941.
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Cancer is a common disease that poses a serious threat to human health. Angiogenesis is essential for the growth and metabolism of tumors, providing oxygen and nutrition for the growth of cells and tissues. However, angiogenesis of tumors depends on the stimulation of growth factors. Vascular Endothelial Growth Factor (VEGFR) is the most unique factor. Therefore, VEGF/VEGFR targeting anticancer drugs are playing an increasingly significant role in clinical trials. In addition, it has been proved that chalcone, the precursor of natural flavonoids, has potential anti-tumor activity, especially anti-angiogenesis activity. This review summarizes the reports about the anti-angiogenesis of chalcone derivatives. Based on the chalcone skeleton, it is divided into substituted chalcones and modified chalcones. The anti-angiogenesis activities of natural or synthetic chalcones, benzene ring modified or connecting bridge modified chalcones are described in this review.
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George, Ginson, Vishal Payyalot Koyiparambath, Sunitha Sukumaran, Aathira Sujathan Nair, Leena K. Pappachan, Abdullah G. Al-Sehemi, Hoon Kim, and Bijo Mathew. "Structural Modifications on Chalcone Framework for Developing New Class of Cholinesterase Inhibitors." International Journal of Molecular Sciences 23, no. 6 (March 14, 2022): 3121. http://dx.doi.org/10.3390/ijms23063121.
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Due to the multifaceted pharmacological activities of chalcones, these scaffolds have been considered one of the most privileged frameworks in the drug discovery process. Structurally, chalcones are α, β-unsaturated carbonyl functionalities with two aryl or heteroaryl units. Amongst the numerous pharmacological activities explored for chalcone derivatives, the development of novel chalcone analogs for the treatment of Alzheimer’s disease (AD) is among the research topics of most interest. Chalcones possess numerous advantages, such as smaller molecular size, opportunities for further structural modification thereby altering the physicochemical properties, cost-effectiveness, and convenient synthetic methodology. The present review highlights the recent evidence of chalcones as a privileged structure in AD drug development processes. Different classes of chalcone-derived analogs are summarized for the easy understanding of the previously reported analogs as well as the importance of certain functionalities in exhibiting cholinesterase inhibition. In this way, this review will shed light on the medicinal chemistry fraternity for the design and development of novel promising chalcone candidates for the treatment of AD.
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Jasim, Hiba A., Lutfun Nahar, Mohammad A. Jasim, Sharon A. Moore, Kenneth J. Ritchie, and Satyajit D. Sarker. "Chalcones: Synthetic Chemistry Follows Where Nature Leads." Biomolecules 11, no. 8 (August 13, 2021): 1203. http://dx.doi.org/10.3390/biom11081203.
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Chalcones belong to the flavonoid class of phenolic compounds. They form one of the largest groups of bioactive natural products. The potential anticancer, anti-inflammatory, antimicrobial, antioxidant, and antiparasitic properties of naturally occurring chalcones, and their unique chemical structural features inspired the synthesis of numerous chalcone derivatives. In fact, structural features of chalcones are easy to construct from simple aromatic compounds, and it is convenient to perform structural modifications to generate functionalized chalcone derivatives. Many of these synthetic analogs were shown to possess similar bioactivities as their natural counterparts, but often with an enhanced potency and reduced toxicity. This review article aims to demonstrate how bioinspired synthesis of chalcone derivatives can potentially introduce a new chemical space for exploitation for new drug discovery, justifying the title of this article. However, the focus remains on critical appraisal of synthesized chalcones and their derivatives for their bioactivities, linking to their interactions at the biomolecular level where appropriate, and revealing their possible mechanisms of action.
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Dhaliwal, Jagjit Singh, Said Moshawih, Khang Wen Goh, Mei Jun Loy, Md Sanower Hossain, Andi Hermansyah, Vijay Kotra, et al. "Pharmacotherapeutics Applications and Chemistry of Chalcone Derivatives." Molecules 27, no. 20 (October 19, 2022): 7062. http://dx.doi.org/10.3390/molecules27207062.
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Chalcones have been well examined in the extant literature and demonstrated antibacterial, antifungal, anti-inflammatory, and anticancer properties. A detailed evaluation of the purported health benefits of chalcone and its derivatives, including molecular mechanisms of pharmacological activities, can be further explored. Therefore, this review aimed to describe the main characteristics of chalcone and its derivatives, including their method synthesis and pharmacotherapeutics applications with molecular mechanisms. The presence of the reactive α,β-unsaturated system in the chalcone’s rings showed different potential pharmacological properties, including inhibitory activity on enzymes, anticancer, anti-inflammatory, antibacterial, antifungal, antimalarial, antiprotozoal, and anti-filarial activity. Changing the structure by adding substituent groups to the aromatic ring can increase potency, reduce toxicity, and broaden pharmacological action. This report also summarized the potential health benefits of chalcone derivatives, particularly antimicrobial activity. We found that several chalcone compounds can inhibit diverse targets of antibiotic-resistance development pathways; therefore, they overcome resistance, and bacteria become susceptible to antibacterial compounds. A few chalcone compounds were more active than conventional antibiotics, like vancomycin and tetracycline. On another note, a series of pyran-fused chalcones and trichalcones can block the NF-B signaling complement system implicated in inflammation, and several compounds demonstrated more potent lipoxygenase inhibition than NSAIDs, such as indomethacin. This report integrated discussion from the domains of medicinal chemistry, organic synthesis, and diverse pharmacological applications, particularly for the development of new anti-infective agents that could be a useful reference for pharmaceutical scientists.
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Ouyang, Yang, Juanjuan Li, Xinyue Chen, Xiaoyu Fu, Si Sun, and Qi Wu. "Chalcone Derivatives: Role in Anticancer Therapy." Biomolecules 11, no. 6 (June 16, 2021): 894. http://dx.doi.org/10.3390/biom11060894.
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Chalcones (1,3-diaryl-2-propen-1-ones) are precursors for flavonoids and isoflavonoids, which are common simple chemical scaffolds found in many naturally occurring compounds. Many chalcone derivatives were also prepared due to their convenient synthesis. Chalcones as weandhetic analogues have attracted much interest due to their broad biological activities with clinical potentials against various diseases, particularly for antitumor activity. The chalcone family has demonstrated potential in vitro and in vivo activity against cancers via multiple mechanisms, including cell cycle disruption, autophagy regulation, apoptosis induction, and immunomodulatory and inflammatory mediators. It represents a promising strategy to develop chalcones as novel anticancer agents. In addition, the combination of chalcones and other therapies is expected to be an effective way to improve anticancer therapeutic efficacy. However, despite the encouraging results for their response to cancers observed in clinical studies, a full description of toxicity is required for their clinical use as safe drugs for the treatment of cancer. In this review, we will summarize the recent advances of the chalcone family as potential anticancer agents and the mechanisms of action. Besides, future applications and scope of the chalcone family toward the treatment and prevention of cancer are brought out.
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Rezende-Júnior, Luís Mário, Leila Maria de Sousa Andrade, Antonio Linkoln Alves Borges Leal, Avilnete Belem de Souza Mesquita, Ana Lurdes Portela de Araújo dos Santos, José de Sousa Lima Neto, José Pinto Siqueira-Júnior, et al. "Chalcones Isolated from Arrabidaea brachypoda Flowers as Inhibitors of NorA and MepA Multidrug Efflux Pumps of Staphylococcus aureus." Antibiotics 9, no. 6 (June 20, 2020): 351. http://dx.doi.org/10.3390/antibiotics9060351.
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Bacterial resistance to antibiotics has become a public health issue around the world. The present study aimed to evaluate the antibacterial activity of chalcones isolated from flowers of Arrabidaea brachypoda, and their potential as efflux pump inhibitors of Staphylococcus aureus efflux pumps. Microdilution assays were performed with natural products from A. brachypoda. Chalcones 1, 3, 4, and 5 did not show intrinsic antimicrobial activity against all S. aureus strains tested, but they were able to potentiate the Norfloxacin action against the SA1199-B (norA) strain, with a better modulating action for the 4 trimethoxylated chalcone. All chalcones were also able to potentiate the action of EtBr against SA1199-B strain, suggesting a potential NorA inhibition. Moreover, chalcone 4 was able to interfere in the activity of MepA, and interfered weakly in the QacA/B activity. Molecular docking analyzes showed that tested chalcones are capable of binding in the hydrophobic cavity of NorA and MepA, in the same Norfloxacin binding site, indicating that chalcone 4 compete with the antibiotic for the same NorA and MepA binding sites. Association of chalcone 4 with Norfloxacin could be an alternative against multidrug resistant S. aureus over-productive of NorA or MepA.
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Tantawy, Mohamed A., Farid M. Sroor, Magda F. Mohamed, Mostafa E. El-Naggar, Fatma M. Saleh, Hamdi M. Hassaneen, and Ismail A. Abdelhamid. "Molecular Docking Study, Cytotoxicity, Cell Cycle Arrest and Apoptotic Induction of Novel Chalcones Incorporating Thiadiazolyl Isoquinoline in Cervical Cancer." Anti-Cancer Agents in Medicinal Chemistry 20, no. 1 (April 10, 2020): 70–83. http://dx.doi.org/10.2174/1871520619666191024121116.
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Background: Chalcones are naturally occurring compounds found in various plant species which are widely used for the traditional popular treatments. Chalcones are distinguished secondary metabolites that are reported to display diverse biological activities such as antiviral, antiplatelet, anti-inflammatory, anticancer, antibacterial and antioxidant agents. The presence of a,ß-unsaturated carbonyl group in chalcones is assumed to be responsible for their bioactivity. In addition, heterocyclic compounds having nitrogen such as isoquinolines are of considerable interest as they constitute the core structural element of many alkaloids that have enormous pharmacological activities. Objective: The objective of this study is the synthesis and biological activity of novel chalcones incorporating thiadiazolyl isoquinoline as potential anticancer candidates. Different genetic tools were used in an attempt to know the mechanism of action of this compound against breast cancer. Methods: An efficient one pot synthesis of novel chalcones incorporating thiadiazolyl isoquinoline has been developed. The cytotoxic activity of the novel synthesized compounds was performed against four different kinds of cancer cell lines. Results: Among all the tested derivatives, chalcone 3 has the best cytotoxic profile against A549, MCF7, and HeLa cell lines, with IC50s (66.1, 51.3, and 85.1μM, respectively). Molecular docking studies for chalcone 3 revealed that CDK2, and EGFRTK domains have strong binding affinities toward the novel chalcone 3, while tubulin-colchicine-ustiloxin, and VEGFRTK domains illustrated moderate mode of binding. Conclusion: We have developed an efficient method for the synthesis of novel chalcones incorporating thiadiazolyl isoquinoline. All compounds showed better cytotoxicity results against four kinds of cancer cell lines (A549, MCF7, HCT116, and HELA cells). The results depicted that chalcone 3 has a high and promising cytotoxic effect against HELA cell line and the mechanism of cytotoxicity was widely studied through different theoretical and experimental tools. Thus, the newly synthesized derivative 3 can be utilized as a novel chemotherapeutic compound for cervical carcinoma.
Dissertations / Theses on the topic "Chalcones"
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Rivera, Sylvie. "Synthèse et réactivité des chalcones." Paris 5, 1997. http://www.theses.fr/1997PA05P150.
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Gomes, Junior Walter Alves. "Aplicações dos heteropoliácidos do tipo Keggin à acilação Friedel-Crafts e à síntese de chalconas." Programa de Pós-Graduação em Química da UFBA, 2008. http://www.repositorio.ufba.br/ri/handle/ri/10020.
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Os heteropoliácidos são polioxometalatos, compostos de um cluster óxido, com prótons associados, apresentando alta acidez de Brönsted, que tem atraído interesse acadêmico e industrial, devido a capacidade de promover catálise “verde”, atuando como catalisador homogênea e heterogênea. Diversas reações orgânicas já foram conduzidas neste sistema catalítico, sendo que a acilação Friedel-Crafts do metoxinaftaleno (2-MN) com anidrido acético (Ac2O) e as condensações de Claisen-Schmidt da acetofenona com benzaldeídos foram testados neste trabalho utilizando heteropoliácidos do tipo Keggin mássico (HPW), suportado em sílica (HPW-SiO2) e na forma de sal de césio (Cs2,2H0,8PW) e de potássio (K2,5H0,5PW). A acilação Friedel-Crafts do 2-MN com anidrido acético foi realizada em fase líquida, utilizando diversos solventes. Os melhores resultados de conversão e seletividade foram obtidos com nitrobenzeno. A máxima conversão foi obtida para concentrações iniciais de reagentes equivalentes ([2-MN]0 = [Ac2O]0). Dos catalisadores utilizados, as melhores conversões foram obtidas com o HPW mássico, que também se mostrou mais seletivo ao 2-acetil-6-metoxinaftaleno , chegando a 90,1%, a 130ºC em 1h de reação. O isômero cineticamente favorável, 1-acetil-2-metoxinaftaleno é formado e logo convertido a 2-acetil-6-metoxinaftaleno a 130ºC em nitrobenzeno. A temperatura de reação afeta a seletividade, mas tem pouco efeito na conversão do 2-MN. As reações de condensação de Claisen-Schmidt da acetofenona com benzaldeídos substituídos (benzaldeido, 4-clorobenzaldeído, 4-nitrobenzaldeído, 4- metoxibenzaldeído e 4-hidroxibenzaldeído) para a síntese de chalconas conduzidas sem o uso de solventes, se mostraram muito efetivas, com conversões e seletividade superiores a 60% e 90%, respectivamente, sobre HPW mássico, em fase homogênea, com uso de pequenas quantidades de catalisador (razão molar substrato/catalisador = 200 ou superior). Os sais de césio e de potássio apresentaram resultados modestos, sendo que estes materiais conduziram reações em fase heterogênea. As reações com benzaldeídos substituídos mostraram grande influência dos grupos substituintes. Além do ótimo desempenho catalítico, esses materiais mostraram possibilidade de regeneração e re-utilização.
Salvador
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Rodriguez, Peña Miguel Angel. "Synthèse et évaluation biologique de dérivés de sulfanyl et sulfonyl chalcones, et du métronidazole, avec une possible activité antimalarique et leishmanicide." Thesis, Bordeaux, 2017. http://www.theses.fr/2017BORD0962/document.
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Ces travaux de thèse décrivent la synthèse de trente-quatre nouveauxdérivés de sulfanyl et de sulfonyl chalcones et de trente-quatre nouveaux dérivés dumétronidazole, ainsi que leurs évaluations biologiques en tant que possibles agentsantipaludiques et leishmanicides. L'évaluation antimalarique in vitro sur la formationde la β-hématine a montré que douze de ces dérivés possèdent une activitéinhibitrice supérieure à 80%. In vivo, deux composés ont conduit à une diminution dela parasitémie au quatrième jour après infection et à une augmentation significativedu temps de survie chez la souris. Dans le cas de l’évaluation leishmanicide in vitro,trois composés ont montré une activité inhibitrice sur la croissance despromastigotes des espèces L. mexicana et L. braziliensis. Les composés les plusactifs sont des dérivés de type benzoate possédant des substituants hydroxyles surles positions 3,4,5 et 3,4 du cycle benzéniqueThis research work describes the chemical synthesis of thirty-four newsulfanyl and sulfonyl chalcone derivatives, and thirty-four new metronidazolederivatives, as well as their biological assays as antimalarial and leishmanicidalagents. The antimalarial in vitro evaluation on the β-hematin formation showed thattwelve of these derivatives display an inhibitory activity higher than 80%. In vivo, twocompounds were found to decrease the parasitaemia by the fourth day after infectionand to increase significantly the survival time of mice. In the case of the in vitroleishmanicidal evaluation, three compounds showed an inhibitory activity on thegrowth of promastigotes of L. mexicana and L. braziliensis species. The most activecompounds are benzoate derivatives featuring hydroxyl substituents at the 3,4,5 and3,4 positions of the benzene ring
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Machado, Carmem Lucia dos Santos. "Estudo da apocinina e diapocinina e seus derivados de chalconas como antioxidante e antibacterianos potenciais: síntese, avaliação da ação antibacteriana, antioxidante e das propriedades físico-químicas." Universidade Federal do Pampa, 2016. http://dspace.unipampa.edu.br:8080/xmlui/handle/riu/533.
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A apocinina é uma acetofenona que apresenta estrutura pequena e possui diversas atividades biológicas. Sua estrutura pode ser oxidada em certas condições químicas ou biológicas e resultar na formação do seu dímero, a diapocinina. As chalconas são compostos que contém em sua estrutura básica a porção 1,3-diarilpro-2-em-1-ona e se caracterizam por apresentar ampla variedade de atividades biológicas, como atividade antioxidante e antibacteriana. Estudos demostram que modificações estruturais nos anéis aromáticos das chalconas resultam na obtenção de compostos com atividade aceptora de radicais e antibacterianas. Neste trabalho foram realizadas a síntese de chalconas derivadas da apocinina e diapocinina, a avaliação da atividade antioxidante e antibacteriana. Adicionalmente foram realizados estudos de modelagem molecular, determinação de propriedades físico-químicas e a avaliação da toxicidade in silico, com a finalidade de se obter compostos que possam ser utilizadas como protótipos a novos fármacos. As chalconas derivadas da apocinina e da diapocinina, com substituintes 4-OCH3, 3,4-OCH3, e 3,4,5-OCH3 ligados ao anel B, e não substituída (H), foram sintetizadas através da condensação de Claisen-Schmidth, dos benzaldeídos com a apocinina e diapocinina, em meio básico, temperatura ambiente, por 24 horas. Ao final de cada reação, os compostos foram analisados e purificados por recristalização ou em cromatografia em coluna. Os compostos foram caracterizados por CCD, ponto de fusão, espectroscopia de infravermelho (IV), e por 1H e 13C RMN. A análise de capacidade aceptora de radicais das moléculas sintetizadas, foram realizadas através do emprego do método colorimétrico de análise do DPPH e ABTS, utilizando como padrão BHT e Trolox, respectivamente, nas concentrações 6,75, 12,5, 25, 50, 100, 200 e 400 μM. A avaliação da atividade antibacteriana dos compostos obtidos foi realizada através do método de difusão ágar-cilindro e leitura de halos de inibição, onde foram testadas as cepas de Staphylococcus aureus ATCC 25923 (bactéria Gram positiva) e Escherichia coli ATCC 25922 (bactéria Gram negativa), utilizando como padrão o antibiótico cloranfenicol. A análise de toxidade in silico, como a genotoxidade, mutagenicidade, efeitos irritante e sobre sistema reprodutor, foi realizado através do programa computacional Osiris Property Explorer. Os compostos apresentaram atividade aceptora do radical DPPH e ABTS na faixa de concentração de 400 a 12,5μM, sendo superiores ao padrão de BHT e Trolox. No ensaio de avaliação da atividade antibacteriana todos os compostos apresentaram atividade antibacteriana frente à cepa Staphylococcus aureus, sendo, no entanto, inferior ao padrão cloranfenicol. Não foi observada atividade contra a cepa Escherichia coli. A partir da análise da toxicidade in silico observou-se que somente os compostos que tinham grupamentos OCH3 substituídos em posição para, apresentaram risco médio e alto para efeito irritante e tóxico para o sistema reprodutor. Os demais compostos apresentaram risco teórico baixo de desenvolver os efeitos tóxicos citados. Diante dos resultados obtidos, observa-se que as chalconas derivadas da apocinina e diapocinina se apresentam como compostos promissores para o estudo e o desenvolvimento de agentes com atividade antioxidante, com ação antibacteriana e baixa toxicidade teórica, sendo assim demonstrando potenciais agentes para se utilizar na terapêutica.
The apocynin is an acetophenone which has little structure and has several biological activities. Its structure can be oxidized in certain chemical or biological conditions and result in the formation of the dimer, the diapocinina. The chalcones are compounds containing in its basic structure portion 1,3-diaryl-pro-2-en-1-one and are characterized by having variety of biological activities such as antibacterial and antioxidant activity. Studies show that structural modifications on the aromatic rings of chalcones result in obtaining the compounds with acceptor radical and antibacterial activity. In this work were performed chalcones derived synthesis of apocynin and diapocinina, the evaluation of antioxidant and antimicrobial activity. It was also performed molecular modeling studies, determination of physicochemical properties and toxicity evaluation in silico, in order to obtain compounds which can be used as prototypes of new drugs. The derivatives of the chalcones and apocynin diapocinina, substituents 4-OCH3, 3,4-OCH3, and 3,4,5-OCH3 attached to B ring, unsubstituted (H) were synthesized by Claisen-Schmidth condensation, of benzaldehydes with apocynin and diapocinina, in basic medium at room temperature for 24 hours. After each reaction, the compounds were analyzed and purified by recrystallization or column chromatography. The compounds were characterized by TLC, melting point, infrared spectroscopy (IR) and 1H and 13C NMR. The acceptor capacity analysis of radical synthesized molecules were carried out by employing the colorimetric method of analysis of DPPH and ABTS using standard as BHT and Trolox, respectively, at concentrations 6.75, 12.5, 25, 50, 100 200 and 400 uM. The evaluation of the antibacterial activity of the obtained compounds was performed by the method of agar-cylinder diffusion and reading inhibition zones, where Staphylococcus aureus ATCC 25923 (Gram positive bacterium) and Escherichia coli ATCC 25922 (Gram negative bacteria) were tested using as standard antibiotic chloramphenicol. The analysis of in silico toxicity, such as genotoxicity, mutagenicity, and irritating effects on reproductive system, was performed using the computer program Osiris Property Explorer. The compounds showed acceptor activity of DPPH and ABTS radical in the concentration range of 400 to 12,5μM, being superior to the standard of BHT and Trolox. The evaluation of the antibacterial activity test all compounds showed antibacterial activity against Staphylococcus aureus strain being, however, lower than the standard chloramphenicol. There was no activity against Escherichia coli strain. From the analysis of in silico toxicity it was observed that only compounds which had OCH3 groups substituted in the para position, exhibited medium and high risk of irritating and toxic effect on the reproductive system. Other compounds showed low theoretical risk of developing toxic effects reported. Considering the results, it is observed that the derivatives of apocynin and diapocinina chalcones present as promising compounds for the study and development of agents having antioxidant activity, antibacterial action and low theoretical toxicity, thus demonstrating potential agents for use in therapy.
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John, Elisa Beatriz de Oliveira. "Desenvolvimento de parâmetros para simulação de flavonoides e chalconas no campo de força GROMOS." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2017. http://hdl.handle.net/10183/180600.
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Chalconas e flavonoides são compostos comumente presentes em plantas, e constituem uma grande família de produtos naturais com um amplo espectro de atividades farmacológicas. Mudanças na estrutura destas moléculas tem se provado úteis no desenvolvimento de novos agentes terapêuticos, sendo assim, esses compostos tem sido intensamente estudados. Métodos computacionais como a dinâmica molecular (DM) são ferramentas poderosas para o acesso a informações de difícil obtenção por outros meios experimentais. Campos de força acurados são essenciais para a descrição de sistemas biológicos em simulações de DM, assim, um conjunto de parâmetros associado a um composto necessita ser cuidadosamente calibrado para garantir a obtenção de resultados confiáveis. Considerando a relevância dessa família de moléculas e a falta de parâmetros validados para a estrutura básica de chalconas e flavonoides no campo de força GROMOS, o presente trabalho tem como objetivo prover um novo conjunto de parâmetros para a simulação destes compostos. Um protocolo que combina cálculos ab initio e simulações de DM foi aplicado para obter novas cargas atômicas e parâmetros torsionais Propriedades experimentais como densidade e entalpia de vaporização foram usadas como comparação aos valores obtidos em simulações, como forma de validação dos parâmetros. A comparação dos perfis torsionais obtidos por cálculos quânticos e por mecânica molecular auxiliou na geração de novos potenciais que permitem uma descrição conformacional mais acurada dos diedros de interesse. Diversos ajustes em grupos de cargas foram feitos, e os valores para propriedades termodinâmicas obtidos nas simulações estão em concordância com os dados experimentais. Simulações de metadinâmica foram realizadas para avaliar o comportamento conformacional de chalconas e flavonoides completos, e contatos de NOE foram medidos durante simulações de DM, obtendo uma reprodução quase completa das distâncias entre alguns grupos de prótons. O protocolo empregado gerou parâmetros de campo de força que reproduzem bem dados experimentais, e espera-se que estes resultados contribuam para a realização de estudos computacionais acurados envolvendo chalconas e flavonoides.Chalcones and flavonoids are polyphenolic compounds extensively distributed in plants, constituting a large family of natural products with a broad spectrum of pharmacological activities. Changes in their structure have been proven useful for the development of new therapeutic agents, thus these biomolecules are being intensively studied and modified. Computational methods such as molecular dynamics (MD) simulations are powerful tools to assess information that is difficult to obtain experimentally. Accurate force fields are essential for describing biological systems in a MD simulation, thus a parameter set associated to a certain compound need to be carefully calibrated to ensure reliable results. Considering the relevance of this family of molecules and the lack of validated parameters for the basic structure of chalcones and flavonoids in the GROMOS force field, this work intends to provide a new parameter set for the simulation of these compounds. We employed a protocol combining ab initio calculations and MD simulations for the obtention of new atomic charges and torsional parameters Experimental properties such as density and enthalpy of vaporization were compared to the calculated values in order to validate the parameters. A fitting of molecular-mechanical to quantum-mechanical torsional profiles was performed for each of the dihedrals of interest in the structures, generating new torsional potentials that provide accurate description of conformational behavior. Additionally, adjustments in charge groups were made in topologies used for the MD simulations and the obtained values of the thermodynamic properties are in good agreement with experimental data. Metadynamics simulations were performed to evaluate the conformation of complete chalcones and flavonoids, and NOE contacts during MD simulations were measured, obtaining an almost complete reproduction of inter-proton interactions. The employed protocol generated force field parameters that reproduce well the target data and we expect they will contribute to more accurate computational studies on the biological role of chalcones and flavonoids.
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Pascoal, Aislan Cristina Rheder Fagundes 1982. "Prospecção de antioxidantes e de substâncias com atividade antiproliferativa em campomanesia adamantium (Myrtaceae)." [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/315310.
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Orientador: Marcos José SalvadorDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: Campomanesia adamantium (Cambess.) O. Berg (Myrtaceae) é uma planta popularmente conhecida como gabiroba ou guaviroba, cujos frutos são comestíveis. Suas folhas e cascas são usadas na medicina popular como antiinflamatórias, antidiarréicas, anti-sépticas das vias urinárias e para o tratamento da gripe. Como parte de um programa de bioprospecção que visa à descoberta de produtos naturais bioativos, o presente estudo teve por objetivo a prospecção de metabólitos secundários com atividade antioxidante e antiproliferativa acumulados no extrato etanólico das folhas de C. adamantium. Para tanto, adequou-se a metodologia para a avaliação in vitro da atividade antioxidante (redução do radical DPPH e ORACFL) e antiproliferativa, frente a linhagens de células tumorais humanas e procedeu-se o estudo fitoquímico, buscando-se a identificação dos constituintes majoritários ativos. Inicialmente obteve-se o perfil dos extratos ativos (HPLC-DAD e ESI-MS), identificando algumas substâncias conhecidas diretamente no extrato bruto e frações (desreplicação). Os extratos ativos foram submetidos ao fracionamento guiado pela atividade antioxidante e antiproliferativa e para a substância isolada e purificada realizou-se a elucidação estrutural utilizando-se métodos espectroscópicos de análise (RMN (1D e 2D ) e espectrometria de massas). Ainda, buscou-se avaliar se a substância purificada induz a morte celular por apoptose frente à linhagem de célula de câncer de próstata (PC-3) com análise de expressão do RNAm por PCR semiquantitativo do genes BAX e BCl-2 e a fragmentação do DNA por citometria de fluxo. Com base nos resultados sugere-se que: (1) o extrato bruto etanólico das folhas de C. adamantium e suas frações butanólica e acetato de etila apresentaram atividade antiproliferativa frente a linhagens tumorais humanas; (2) o extrato bruto etanólico das folhas de C. adamantium e suas frações butanólica e acetato de etila apresentaram atividade antioxidante tanto pelo método indireto DPPH (baseado em mecanismos de transferência de elétrons), quanto pelo ensaio ORACFL (método direto, cinético, baseado em mecanismos de transferência de hidrogênio). A atividade antioxidante destas amostras pode ser relacionada com o alto teor de substâncias fenólicas totais solúveis estimado pelo método colorimétrico Folin Ciocalteu; (3) análises empregando HPLC-DAD e ESI-MS e MS-MS dos extratos e frações com atividade antioxidante sugeriram a presença dos flavonóides isoquercitrina (Ca1), quercitrina (Ca2), miricetina (Ca3), quercetina (Ca4) e das chalconas 2',4'-diidroxi-6'-metoxichalcona (Ca5), 2',4'-diidroxi-5'-metil-6'-metoxichalcona (Ca6) e 2',4'-diidroxi-3',5'-dimetil-6'-metoxichalcona (Ca7); (4) o estudo fitoquímico da fração acetato de etila levou ao isolamento e identificação da chalcona Ca5, que apresentou promissora atividade antiproliferativa frente a algumas das linhagens de células tumorais humanas estudadas; (5) as análises de expressão dos genes BAX e BCl-2 não apresentaram alterações significativas em relação às células controles que indicassem indução de apoptose. Porém, com a análise por citometria de fluxo da fragmentação do DNA pode-se observar que as células que foram tratadas com a chalcona isolada (Ca5) tiveram um aumento significativo da fragmentação, indicando indução do processo apoptótico. Assim, procedeu-se o estudo com C. adamantium para a busca de compostos com atividade antioxidante e antiproliferativa de origem vegetal, o que pode vir a contribuir para a quimioprevenção de doenças relacionadas com o estresse oxidativo (doenças degenerativas, câncer, cardiovasculares, inflamatórias) e para obter novas fontes de insumos farmacêuticos
Abstract: Campomanesia adamantium (Cambess.) O. Berg (Myrtaceae) is a plant popularly known as gabiroba or guaviroba, whose fruits are edible. Its leaves and bark are used in folk medicine as anti-inflammatory, antidiarrheal, antiseptic of the urinary tract and treatment of flu. As part of a bioprospecting program aimed at the discovery of bioactive natural products, this study aims at prospecting with phyto-derived antioxidant and antiproliferative activity accumulated in the ethanol extract from leaves of C. adamantium. To this end, it has adapted methods for in vitro evaluation of antioxidant activity (DPPH radical reduction and ORACFL assays) and antiproliferative activity against human tumor cell lines and proceeded to the phytochemical study, seeking to identify the major constituents active. Initially, we obtained the profile of the active extracts (HPLC-DAD and ESI-MS), identifying some known substances directly into the crude extract and fractions (dereplication). The active extracts were subjected to fractionation guided by the antioxidant and antiproliferative activities and the compound isolated and purified held structural elucidation using spectroscopic analysis (NMR (1D and 2D) and mass spectrometry). Still, we sought to assess whether the purified substance induces cell death by apoptosis front of the cell line of prostate cancer (PC-3) with analysis of mRNA expression by semiquantitative PCR of the genes BAX and BCL-2 and DNA fragmentation by flow cytometry. The results suggest that: (1) the crude ethanol extract of leaves of C. adamantium and its fractions in butanol and ethyl acetate showed antiproliferative activity against human tumor lines; (2) the crude ethanol extract of leaves of C. adamantium and its fractions butanol and ethyl acetate showed antioxidant activity proved both by DPPH method (based on mechanisms of electron transfer), and by the ORACFL assay (kinetic method based on mechanisms of hydrogen transfer). The antioxidant activity of these samples may be related to the high content of total soluble phenolic substances estimated by the Folin Ciocalteu colorimetric assay; (3) analysis employing HPLC-DAD, ESI-MS and MS-MS of extracts and fractions with antioxidant activity suggested the presence of flavonoids isoquercitrin (Ca1), quercitrin (Ca2), myricetin (Ca3), quercetin (Ca4) chalcones and 2 ', 4'-dihydroxy- 6'-metoxichalcona (Ca5), 2', 4'-dihydroxy-5'-methyl-6 '-metoxichalcona (Ca6) and 2', 4'-dihydroxy-3 ', 5'-dimethyl-6'-metoxichalcona (Ca7); (4) the phytochemical study of ethyl acetate fraction led to the isolation and identification of the chalcone Ca5 which showed promising antiproliferative activity against some human tumor cell lines studied; (5) analysis of gene expression of BAX and BCL-2 showed no changes, but DNA fragmentation can be observed apoptosis in cells that were treated with chalcone Ca5. Thus, we proceeded the study of C. adamantium to search of natural products with antioxidant and antiproliferative activities, to contribute to the chemoprevention of diseases related to oxidative stress (degenerative diseases, cancer, cardiovascular, inflammatory) and to obtain new sources of pharmaceutical products
Mestrado
Biologia Vegetal
Mestre em Biologia Vegetal
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Lipinski, Célio Fernando. "Estudo de relações quantitativas estrutura-atividade de chalconas análogas à combretastatina A4." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/75/75134/tde-07052015-112219/.
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A combretastatina A4 é um promissor agente anticâncer. Na célula, inibe a polimerização dos microtúbulos, os quais são fundamentais nos processos de motilidade, manutenção estrutural e mitose. Essa inibição se dá a partir do sítio de interação da αβ-tubulina bloqueando o fluxo do sangue que alimenta os tumores, o que resulta na morte dos mesmos. Com estrutura semelhante às combretastatinas, as chalconas constituem uma classe de compostos que atuam no mesmo sítio de interação na tubulina. Baseando-se nos trabalhos experimentais de Ducki e colaboradores, estudou-se a estrutura molecular de 87 chalconas análogas à combretastatina A4 por meio do método quântico DFT com o propósito de desenvolver modelos de Relações Quantitativas Estrutura-Atividade (QSAR) aplicados a tais antagonistas. A partir dos métodos dos Mínimos Quadrados Parciais (PLS) e de Redes Neurais Artificiais (ANN), foram gerados modelos que conduzem à elucidação da relação dos compostos estudados com suas respectivas atividades biológicas. Os descritores eletrônicos e moleculares selecionados apresentam alta concordância com as características das moléculas, havendo predominância de comportamento linear com a atividade biológica, podendo, eventualmente, apresentar comportamento não-linear, o que torna o modelo gerado altamente consistente.Combretastatin A4 is a promising anticancer agent. It inhibits the polymerization of microtubules in the cell, which are essential in the process of motility, structural maintenance and mitosis. This inhibition is given from the interaction site of αβ-tubulin blocking the blood flow that feeds the tumor, what results in its death. The chalcones, sharing a similar structure of the combretastatin, are also a class of compounds that act in the same site of interaction in the tubulin. Based on the experimental work of Ducki and co-workers, we proposed a molecular structure study of 87 chalcones similar to combretastatin A4 using the DFT method in order to develop Quantitative Structure-Activity Relationships (QSAR) applied to the given antagonists. Through Partial Least Squares (PLS) and Artificial Neural Network (ANN) methods, some models has been generated to lead the understanding on the relationship between the compounds studied and their respective biological activities. The electronic and molecular descriptors selected have high correlation with the molecule features, being linear most of the time, although with eventual non-linear behavior, which makes the generated model highly consistent.
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Bocelli, Marcio David. "Estudo da atividade de chalconas no controle de biofilmes bacterianos." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/75/75133/tde-17112016-141016/.
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Os biofilmes constituem uma forma de crescimento que permite a maior sobrevivência e resistência de microrganismos a agentes de controle como antibióticos e desinfetantes. Apesar da grande disponibilidade de agentes antimicrobianos no mercado, há escassez de produtos específicos e efetivos na erradicação/inibição de biofilmes. Existe atualmente grande interesse na seleção de moléculas capazes de inibir o crescimento dos biofilmes ou removê-los quando já estabelecidos. Doenças como fibrose cística (P. aeruginosa) e cárie dentária (S. mutans), são patologias intrinsecamente ligadas à formação de biofilmes. O principal objetivo deste trabalho foi avaliar o potencial de chalconas sintéticas e derivados no controle e erradicação de biofilmes. As chalconas foram testadas quanto à capacidade de inibir a formação de biofilme e de remover biofilmes pré-estabelecidos. Os biofilmes de P. aeruginosa foram inibidos pela presença da molécula (E)-1-(3-hidroxinaftalen-2-il)-3-fenilprop-2-em-1-ona (11), mostrando redução de 48,8% na biomassa e 60,2% na viabilidade. A redução máxima na biomassa atingiu 70,9%. Já para o tratamento de biofilmes pré-estabelecidos, a molécula (1E,4E)-1,5-difenilpenta-1,4-dien-3-ona (10) mostrou redução de 53,5% na biomassa do biofilme de P. aeruginosa. Na formação do biofilme de S. mutans, a presença da molécula (1E, 4E)-1,5-bis(4-bromofenil)penta-1,4-dien-3-ona (15) reduziu a biomassa em 67,4%. Em concentrações elevadas essa redução chegou a 95,1%. Em biofilmes pré-estabelecidos de S. mutans, o tratamento com a molécula (2E,4E)-1,5-difenilpenta-2,4-dien-1-ona (12) reduziu a biomassa celular em 62,7%, e a viabilidade celular em 58,4%. Já a molécula (E)-3-(2-hidroxifenil)-1-fenilprop-2-en-1-ona (21), quando utilizada no tratamento de biofilmes pré-estabelecidos, mostrou redução de 26,4% na biomassa e 91,6% na viabilidade de S. mutans; além de evidenciar danos à estrutura celular do microrganismo. Todas as moléculas supracitadas promoveram redução na espessura dos biofilmes. Os antibióticos ampicilina e polimixina foram menos eficientes na remoção de biofilmes comparativamente às moléculas testadas. As moléculas não apresentaram CIM frente às bactérias, entretanto, afetaram a viabilidade celular. O tratamento da superfície de poliestireno com as chalconas não impediu a adesão das bactérias, e resultou na redução da hidrofobicidade do material. A superfície celular de S. mutans apresentou predomínio de cargas negativas e forte caráter hidrofóbico enquanto que P. aeruginosa apresentou baixa hidrofobicidade além de caráter básico. Os resultados evidenciam a potencialidade do uso das chalconas e seus derivados para o controle e erradicação de biofilmes Streptococcus mutans e Pseudomonas aeruginosa.Biofilms constitute a growth mode which allows greatest survival and resistance of microorganisms to antibiotics and disinfectants. Despite the wide availability of antimicrobial agents in the market, there are few specific and effective products to the eradication / inhibition of biofilms. Thus, there is a great interest in the search of molecules able to inhibit biofilms or remove them once established. Diseases such as cystic fibrosis (P. aeruginosa) and dental caries (S. mutans), are intrinsically linked to the formation of biofilms. The aim of this study was to evaluate the potential of chalcones and their synthetic derivatives to the control and eradication of biofilms. The chalcones were tested for the ability to inhibit biofilm formation and also to remove pre-established biofilms. Biofilms of P. aeruginosa was inhibited by the presence of the molecule (E) -1- (3-hydroxynaphthalen-2-yl) -3-phenylprop-2-en-1-one (11) showing reduction of 48.8% biomass and 60.2% viability. The maximum reduction in biomass reached 70.9%. For the treatment of pre-established biofilms, the molecule (1E, 4E) -1,5-difenilpenta-1,4-dien-3-one (10) showed a 53.5% reduction in biomass of P. aeruginosa biofilm. Biofilms of S. mutans, growing in the the presence of the molecule (1E, 4E) -1,5-bis (4-bromophenyl) penta-1,4-dien-3-one (15) showed a biomass reduction of 67.4 %. At higher concentrations this reduction reached 95.1%. In pre-established biofilms of S. mutans, treatment with the molecule (2E, 4E) -1,5-difenilpenta-2,4-dien-1-one (12) reduced cell biomass in 62.7%, and cell viability by 58.4%. The molecule (E) -3- (2-hydroxyphenyl) -1-phenylprop-2-en-1-one (21), when used in the treatment of pre-established biofilms, showed 26.4% reduction in biomass and 91.6% in the viability of S. mutans; furthermore, the chalcone 21 caused damage to the cellular structure of the microorganism. All the aforementioned molecules promoted a reduction in the thickness of biofilms. The antibiotics polymyxin and ampicillin were less efficient on removing biofilms comparatively to the chalcones. The molecules affected cell viability however, no MIC was observed under the range of concentrations evaluated. The treatment of the polystyrene surface with chalcones did not prevent bacterial adhesion moreover, hydrophobicity of the material was reduced. S. mutans cell surface showed a predominance of negative charges and strong hydrophobic character while P. aeruginosa showed low hydrophobicity and basic character. The results demonstrate that synthetic chalcones and derivatives are potential candidates to the control and eradication of Streptococcus mutans and Pseudomonas aeruginosa biofilms.
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Dridi, Delel. "Synthèse de dérivés coumariniques d’intérêts biologiques et antioxydants." Thesis, Université de Lorraine, 2015. http://www.theses.fr/2015LORR0335/document.
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Dans le cadre des travaux développés sur les coumarines et autres flavonoïdes au laboratoire (aurones inhibitrices de NFkB, polycycles chromaniques inhibiteurs de CDC25), le travail de la thèse a consisté à poursuivre dans ce domaine en construisant de nouvelles chalcones à partir de dérivés acétylés de coumarines par condensation avec des aldéhydes cinnamiques préparées suivant différentes méthodes. Les chalcones ainsi préparées ont été étudiées pour les effets antioxydants en utilisant la spectrophotométrie ainsi que pour l’inhibition des phosphatases CDC25As part of the work developed on coumarin and other flavonoids in our laboratory (aurones as potential NFK-B inhibitors, chromanic polycycles as CDC25 phosphatases inhibitors), the aim of this thesis was to pursue the research in this area by synthesizing new chalcones from acetylated coumarines derivatives by condensation with cynnamic aldehydes prepared by different methods. The prepared chalcones were studied for their antioxidant activity using spectrophotometry and for their inhibition of CDC25 phosphatases
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Kandepu, Narayana Murthi. "Mannich bases of chalcones and cyclohexanones as candidate cytotoxic agents." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape7/PQDD_0035/NQ63974.pdf.
Full textBooks on the topic "Chalcones"
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Litwin, Andrej. Chalcogen dopants in silicon electronic devices. [s.l.]: [s.n.], 1985.
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Larsson, Kaj. Optical and electrical studies of chalcogen-doped silicon and germanium. [s.l.]: [s.n.], 1986.
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Koes, Ronald Edwin. Genes involved in flavonoid biosynthesis in Petunia hybrida: The chalcone synthase multigene family. [s.l.]: [s.n.], 1988.
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A, Devillanova Francesco, ed. Handbook of chalcogen chemistry: New perspectives in sulfur, selenium and tellurium. Cambridge: RSC Pub., 2007.
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Devillanova, Francesco A. Handbook of chalcogen chemistry: New perspectives in sulfur, selenium and tellurium. Cambridge: Royal Society of Chemistry, 2007.
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1st, Konda Shankaraiah G. Systematic Synthesis of Chalcones. INSC International Publisher (IIP), 2021.
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Perjési, Pà l. Chalcones and Their Synthetic Analogs. Nova Science Publishers, Incorporated, 2020.
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Perjési, Pál. Chalcones and Their Synthetic Analogs. Nova Science Publishers, Incorporated, 2020.
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Papoh Ndibewu, Peter, ed. Chalcogen Chemistry. IntechOpen, 2019. http://dx.doi.org/10.5772/intechopen.73066.
Full textBook chapters on the topic "Chalcones"
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Suharoschi, Ramona, Oana Lelia Pop, Călina Ciont, Carmen Ioana Muresan, and Simona Codruţa Hegheş. "Chalcones." In Handbook of Food Bioactive Ingredients, 365–406. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-28109-9_10.
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Suharoschi, Ramona, Oana Lelia Pop, Călina Ciont, Carmen Ioana Muresan, and Simona Codruţa Hegheş. "Chalcones." In Handbook of Food Bioactive Ingredients, 1–42. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-030-81404-5_10-1.
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Mah, Siau Hui. "Chalcones in Diets." In Handbook of Dietary Phytochemicals, 1–52. Singapore: Springer Singapore, 2019. http://dx.doi.org/10.1007/978-981-13-1745-3_10-1.
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Mah, Siau Hui. "Chalcones in Diets." In Handbook of Dietary Phytochemicals, 273–324. Singapore: Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-15-4148-3_10.
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Ninomiya, Masayuki, and Mamoru Koketsu. "Minor Flavonoids (Chalcones, Flavanones, Dihydrochalcones, and Aurones)." In Natural Products, 1867–900. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-22144-6_62.
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Nielsen, Simon F., S. B. Christensen, A. Kharazmi, and Tommy Liljefors. "Antileishmanial Chalcones: Statistical Design and 3D-QSAR Analysis." In Molecular Modeling and Prediction of Bioactivity, 316–17. Boston, MA: Springer US, 2000. http://dx.doi.org/10.1007/978-1-4615-4141-7_57.
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Misra, Ram A. "Reactivity of Superoxide Ion with Organohalogens and Chalcones." In Novel Trends in Electroorganic Synthesis, 275–77. Tokyo: Springer Japan, 1998. http://dx.doi.org/10.1007/978-4-431-65924-2_83.
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Nath, Shreya, Anish Nag, Swarnali Dey, Rita Kundu, and Subhabrata Paul. "Involvement of Chalcones and Coumarins in Environmental Stress Tolerance." In Biology and Biotechnology of Environmental Stress Tolerance in Plants, 191–226. New York: Apple Academic Press, 2023. http://dx.doi.org/10.1201/9781003346173-10.
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Mahapatra, Debarshi Kar, Vivek Asati, and Sanjay Kumar Bharti. "Promising Anticancer Potentials of Natural Chalcones as Inhibitors of Angiogenesis." In Natural Products Chemistry, 253–68. Names: Volova, Tatiana G., editor. | Mahapatra, Debarshi Kar, editor. | Khanna, Sonia, editor. | Haghi, A. K., editor. Description: Includes bibliographical references and index.: Apple Academic Press, 2020. http://dx.doi.org/10.1201/9781003000693-11.
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Ghoran, Salar Hafez, Fatemeh Taktaz, Pouya Alipour, Farah Khameis Farag Teia, Pascal D. Douanla, and Amna Hamad Abdallah Atia. "Anti-SARS-CoV-2 Activity of Chalcones and Their Synthetic Derivatives." In Anti-SARS-CoV-2 Activity of Flavonoids, 125–39. Boca Raton: CRC Press, 2024. http://dx.doi.org/10.1201/9781003433200-10.
Full textConference papers on the topic "Chalcones"
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Septianingtyas, Dewi, Nahda Zafira, Zulhipri, Fera Kurniadewi, and Hanhan Dianhar. "Green synthesis of chalcones derivatives." In THE 2ND SCIENCE AND MATHEMATICS INTERNATIONAL CONFERENCE (SMIC 2020): Transforming Research and Education of Science and Mathematics in the Digital Age. AIP Publishing, 2021. http://dx.doi.org/10.1063/5.0042002.
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Silva, Marina Goulart da, Graziele Diniz da Silva, Clebson L.Veber, Andersson Barison, Gustavo H. R. Viana, and José Augusto F. P. Villar. "Design and synthesis of triazole-chalcones." In 14th Brazilian Meeting on Organic Synthesis. São Paulo: Editora Edgard Blücher, 2013. http://dx.doi.org/10.5151/chempro-14bmos-r0263-1.
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Santos, *Mariana Bastos dos, Fernanda Patricia Gullo, Luiz Antonio Dutra, Maria José Soares Mendes-Giannini, Ana Marisa Fusco-Almeida, and Luis Octávio Regasini. "Preparation of New Prenylated (E)-Chalcones." In 15th Brazilian Meeting on Organic Synthesis. São Paulo: Editora Edgard Blücher, 2013. http://dx.doi.org/10.5151/chempro-15bmos-bmos2013_201382002510.
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Kurniadewi, F., Y. M. Syah, L. D. Juliawaty, E. H. Hakim, K. Koyama, and K. Kinoshita. "Cytotoxic chalcones from some Indonesian Cryptocarya." In INTERNATIONAL SYMPOSIUM ON CURRENT PROGRESS IN MATHEMATICS AND SCIENCES 2016 (ISCPMS 2016): Proceedings of the 2nd International Symposium on Current Progress in Mathematics and Sciences 2016. Author(s), 2017. http://dx.doi.org/10.1063/1.4991189.
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Lazić, Anita, Luka Matović, Jelena Lađarević, Aleksandra Mašulović, Kristina Gak Simić, and Nataša Valentić. "In vitro antioxidant activity evaluation of ferrocenyl chalcones." In 36th International Congress on process engineering. SMEITS, 2023. http://dx.doi.org/10.24094/ptk.023.207.
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Ferrocene derivatives are known as antioxidants, antiparasitic, antitumor, antiviral, antibacterial and antifungal agents. In addition to applications in medicinal chemistry and drug design, ferrocene derivatives are of exceptional importance in synthetic organic chemistry, especially in catalytic asymmetric transformations. They are also used in electrochemistry and polymer chemistry, as additives in fuels, as chemosensors in agrochemistry and biosensors of glucose and active components in molecular electronics. To design new antioxidant agents, five ferrocenyl chalcones were synthesized, and fully characterized by melting points, FT-IR, 1H and 13C NMR spectroscopic methods. The synthesized chalcones differ in the nature and the position of the substituent attached to the phenyl group in position 1 of the linear unsaturated carbonyl system. The potential antioxidant activity of the synthesized compounds was evaluated using the ABTS (2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) method and IC50 values of the most effective compounds were further determined.
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Rocha, Sílvia, Álvaro Tomé, Ana Teresa Rufino, Marisa Freitas, Félix Carvalho, Artur Silva, and Eduarda Fernandes. "Chalcones as Potential Inhibitors of Pancreatic Lipase." In International Electronic Conference on Medicinal Chemistry. Basel Switzerland: MDPI, 2022. http://dx.doi.org/10.3390/ecmc2022-13413.
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Keta, Otilija, Vladana Petković, Neda Đorđević, Miloš Đorđević, Branka Ivković, and Vladimir Dobričić. "The effects of a selected methoxy substituted chalcone in human melanoma cells irradiated with γ-rays." In 2nd International Conference on Chemo and Bioinformatics. Institute for Information Technologies, University of Kragujevac, 2023. http://dx.doi.org/10.46793/iccbi23.471k.
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Given the well-established potential of chalcones in modulating the response of cancer cells to therapeutic interventions, coupled with the growing imperative to enhance their biological attributes, the objective of this study was to synthesize a methoxy-substituted chalcone (OCH3) and assess its capacity to amplify the inhibitory effects of radiation in melanoma cells known for their resistance to radiotherapy. The A375 melanoma cells were subjected to a clinically relevant dose of 2 Gy gamma irradiation. OCH3 was employed either as a standalone treatment or in conjunction with irradiation. The obtained results unveiled the substantial radiosensitizing potential of OCH3 within this specific cell line. Our subsequent investigations will be designed to investigate the underlying mechanisms that contribute to the radiosensitizing properties of OCH3. Moreover, we intend to evaluate the efficacy of OCH3 against other types of radioresistant cancer cells. The presented data not only illuminates the enhanced therapeutic possibilities offered by OCH3 but also highlights its potential as a valuable agent in addressing a wider array of challenging malignancies.
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Hussein, Ola, Feras Alali, Ala‐Eddin Al Mustafa, and Ashraf Khalil. "Development of Novel Chalcone Analogs as Potential Multi-Targeted Therapies for Castration-Resistant Prostate Cancer." In Qatar University Annual Research Forum & Exhibition. Qatar University Press, 2021. http://dx.doi.org/10.29117/quarfe.2021.0114.
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Prostate cancer (PCa) is the second most frequently diagnosed malignancy, as well as a leading cause of cancer-related mortality in men globally. Despite the initial response to hormonal targeted therapy, the majority of patients ultimately progress to a lethal form of the disease, castration-resistant prostate cancer (CRPC). Therefore, the objective of this study was to discover and develop novel treatment modalities for CRPC. Chalcones are among the highly attractive scaffolds being investigated for their antitumor activities. A library of 26 chalcone analogs were designed, synthesized and evaluated as potential therapies for CRPC. The design was guided by in-silico ADMET prediction in which analogs with favorable drug-likeness properties were prioritized. The new compounds were synthesized, purified and characterized by extensive structural elucidation studies. The compounds in vitro cytotoxicity was evaluated against two androgen receptor (AR)-negative prostate cancer cell lines (PC3 and DU145). Among the tested compounds, pyridine containing analogs (13, 15 and 16) showed potent antiproliferative activities with IC50 values ranging between 4.32-6.47 µM against PC3 and DU145 cell lines. Detailed biological studies of the lead molecule 16 revealed that it can significantly induce apoptosis through upregulation of Bax and downregulation of Bcl-2. In addition, compound 16 potently inhibited colony formation and reduced cell migration of AR-negative PCa cell lines (PC3 and DU145). The molecular pathway analysis showed that the anticancer activity of compound 16 is associated with blocking of ERK1/2 and Akt activities. Furthermore, compound 16 inhibited angiogenesis in the chick chorioallantoic membrane (CAM) model as compared to control. Structure-activity relationship study revealed that the cytotoxicity could dramatically improve via changing the methoxylation pattern by more than 2-folds (IC50 << 2.5 μM). These results indicate that pyridine-based chalcones could serve as promising lead molecules for the treatment of CRPC; thus, further in vitro and in vivo studies are warranted.
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Tran, Thanh-Dao, Cat-Dong Tran, Khac-Minh Thai, Tuong-Ha Do, and Thao-Nhu Nguyen. "Synthesis and Antimicrobial Activity of Novel Heterocyclic Chalcones." In The 15th International Electronic Conference on Synthetic Organic Chemistry. Basel, Switzerland: MDPI, 2011. http://dx.doi.org/10.3390/ecsoc-15-00789.
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Silva, Wender A., Lennine R. Melo, and Júlia Galvez B. Pedreira. "Microwave Assisted Reduction of Chalcones: A Versatile Method." In 14th Brazilian Meeting on Organic Synthesis. São Paulo: Editora Edgard Blücher, 2013. http://dx.doi.org/10.5151/chempro-14bmos-r0352-1.
Full textReports on the topic "Chalcones"
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Riley, Brian J., David A. Pierce, and Jaehun Chun. Efforts to Consolidate Chalcogels with Adsorbed Iodine. Office of Scientific and Technical Information (OSTI), August 2013. http://dx.doi.org/10.2172/1097940.
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Riley, Brian J., William C. Lepry, Jaehun Chun, and Denis M. Strachan. Initial Assessment of Alternate Metals in Chalcogels. Office of Scientific and Technical Information (OSTI), June 2012. http://dx.doi.org/10.2172/1045128.
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Mazur, Eric. Femtosecond Laser Microstructuring and Chalcogen Inclusion in Silicon. Fort Belvoir, VA: Defense Technical Information Center, February 2011. http://dx.doi.org/10.21236/ada544798.
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Riley, Brian J., and William C. Lepry. Initial Assessment of the Consolidation of Chalcogels into a Viable Waste Form. Office of Scientific and Technical Information (OSTI), August 2012. http://dx.doi.org/10.2172/1051204.
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Campbell, Stephen, A. Final Scientific Report : Development of Transition Metal/ Chalcogen Based Cathode Catalysts for PEM Fuel Cells. Office of Scientific and Technical Information (OSTI), February 2008. http://dx.doi.org/10.2172/924399.
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Eyal, Yoram, Gloria Moore, and Efraim Lewinsohn. Study and Manipulation of the Flavanoid Biosynthetic Pathway in Citrus for Flavor Engineering and Seedless Fruit. United States Department of Agriculture, October 2003. http://dx.doi.org/10.32747/2003.7570547.bard.
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The proposal was aimed to identify and functionally characterize key genes/enzymes in the citrus flavanone neohesperidoside biosynthetic pathway and to use them as tools for metabolic engineering to decrease bitterness levels in grapefruit. The proposed section on fruit seediness was dropped as suggested by the reviewers of the proposal. Citrus flavor and aroma is composed of complex combinations of soluble and volatile compounds. The former includes mainly sugars, acids and flavanones, a subgroup of flavonoids that includes bitter compounds responsible for the bitter flavor of grapefruit and pummelo. Bitter species contain mostly bitter flavanone neohesperidosides, while non-bitter species contain mostly tasteless flavanone rutinosides. Both flavanone versions are diglycosides consisting of a rhamnose-glucose oligosaccharide a-linked at position 7 to the flavanone skeleton. However, in the bitter neohesperidosides the rhamnose is attached at position 2 of the glucose moiety, while in the tasteless rutinosides the rhamnose is attached at position 6 of the glucose moiety. Thus, the position of the rhamnose moiety, determined by the specificity of the last enzymes in the pathway- rhamnosyltransferase (1,2 or 1,6 specificity), is the determinant of the bitter flavor. Flavanones, like all flavonoids are synthesized via one of the branches of the phenylpropanoid pathway; the first committed step is catalyzed by the enzyme Chalcone synthase (CHS) followed by Chalcone isomerase (CHI). During the course of the work a key gene/enzyme in the biosynthesis of the bitter flavanones, a 1,2 rhamnosyltransferase (1,2RT), was functionally characterized using a transgenic cell-culture biotransformation system, confirming that this gene is a prime candidate for metabolic engineering of the pathway. This is the first direct functional evidence for the activity of a plant recombinant rhamnosyltransferase, the first confirmed rhamnosyltransferase gene with 1,2 specificity and the second confirmed rhamnosyltransferase gene altogether in plants. Additional genes of the flavanone pathway that were isolated during this work and are potential tools for metabolic engineering include (I) A putative 1,6 rhamnosyltransferase (1,6RT) from oranges, that is presumed to catalyze the biosynthesis of the tasteless flavanones. This gene is a prime candidate for use in future metabolic engineering for decreased bitterness and is currently being functionally characterized using the biotransformation system developed for characterizing rhamnosyltransferases. (2) A putative 7-0-glucosyltransferase presumed to catalyze the first glycosylation step of the flavanone aglycones. Silencing of gene expression in grapefruit was attempted using three genes: (1) The "upstream" flavonoid biosynthesis genes CHS and CHI, by antisense and co-suppression; and (2) The "downstream" 1,2R T, by an RNAi approach. CHS and CHI silencing resulted in some plants with a dramatically decreased level of the bitter flavanone neohesperidoside naringin in leaves. We have yet to study the long-term effect of silencing these genes on tree physiology, and on the actual bitterness of fruit. The effect of 1,2RT silencing on naringin content in grapefruit has yet to be examined, but a slow growth phenotype for these plants was noted. We speculate that silencing of the final glycosylation step of the flavanones delays their evacuation to the vacuole, resulting in accumulation of flavanones in the cytoplasm, causing inhibitory effects on plant growth. This speculation is yet to be established at the product level. Future metabolic engineering experiments are planned with 1,6RT following functional characterization.
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Phillips, Donald, and Yoram Kapulnik. Using Flavonoids to Control in vitro Development of Vesicular Arbuscular Mycorrhizal Fungi. United States Department of Agriculture, January 1995. http://dx.doi.org/10.32747/1995.7613012.bard.
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Vesicular-arbuscular mycorrhizal (VAM) fungi and other beneficial rhizosphere microorganisms, such as Rhizobium bacteria, must locate and infect a host plant before either symbiont profits. Although benefits of the VAM association for increased phosphorous uptake have been widely documented, attempts to improve the fungus and to produce agronomically useful amounts of inoculum have failed due to a lack of in vitro production methods. This project was designed to extend our prior observation that the alfalfa flavonoid quercetin promoted spore germination and hyphal growth of VAM fungi in the absence of a host plant. On the Israeli side of the project, a detailed examination of changes in flavonoids and flavonoid-biosynthetic enzymes during the early stages of VAM development in alfalfa found that VAM fungi elicited and then suppressed transcription of a plant gene coding for chalcone isomerase, which normally is associated with pathogenic infections. US workers collaborated in the identification of flavonoid compounds that appeared during VAM development. On the US side, an in vitro system for testing the effects of plant compounds on fungal spore germination and hyphal growth was developed for use, and intensive analyses of natural products released from alfalfa seedlings grown in the presence and absence of microorganisms were conducted. Two betaines, trigonelline and stachydrine, were identified as being released from alfalfa seeds in much higher concentrations than flavonoids, and these compounds functioned as transcriptional signals to another alfalfa microsymbiont, Rhizobium meliloti. However, these betaines had no effect on VAM spore germination or hyphal growth i vitro. Experiments showed that symbiotic bacteria elicited exudation of the isoflavonoids medicarpin and coumestrol from legume roots, but neither compound promoted growth or germination of VAM fungi in vitro. Attempts to look directly in alfalfa rhizosphere soil for microbiologically active plant products measured a gradient of nod-gene-inducing activity in R. meliloti, but no novel compounds were identified for testing in the VAM fungal system in vitro. Israeli field experiments on agricultural applications of VAM were very successful and developed methods for using VAM to overcome stunting in peanuts and garlic grown in Israel. In addition, deleterious effects of soil solarization on growth of onion, carrot and wheat were linked to effects on VAM fungi. A collaborative combination of basic and applied approaches toward enhancing the agronomic benefits of VAM asociations produced new knowledge on symbiotic biology and successful methods for using VAM inocula under field conditions
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Droby, Samir, Michael Wisniewski, Ron Porat, and Dumitru Macarisin. Role of Reactive Oxygen Species (ROS) in Tritrophic Interactions in Postharvest Biocontrol Systems. United States Department of Agriculture, December 2012. http://dx.doi.org/10.32747/2012.7594390.bard.
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To elucidate the role of ROS in the tri-trophic interactions in postharvest biocontrol systems a detailed molecular and biochemical investigation was undertaken. The application of the yeast biocontrol agent Metschnikowia fructicola, microarray analysis was performed on grapefruit surface wounds using an Affymetrix Citrus GeneChip. the data indicated that 1007 putative unigenes showed significant expression changes following wounding and yeast application relative to wounded controls. The expression of the genes encoding Respiratory burst oxidase (Rbo), mitogen-activated protein kinase (MAPK) and mitogen-activated protein kinase kinase (MAPKK), G-proteins, chitinase (CHI), phenylalanine ammonia-lyase (PAL), chalcone synthase (CHS) and 4-coumarate-CoA ligase (4CL). In contrast, three genes, peroxidase (POD), superoxide dismutase (SOD) and catalase (CAT), were down-regulated in grapefruit peel tissue treated with yeast cells. The yeast antagonists, Metschnikowia fructicola (strain 277) and Candida oleophila (strain 182) generate relatively high levels of super oxide anion (O2−) following its interaction with wounded fruit surface. Using laser scanning confocal microscopy we observed that the application of M. fructicola and C. oleophila into citrus and apple fruit wounds correlated with an increase in H2O2 accumulation in host tissue. The present data, together with our earlier discovery of the importance of H₂O₂ production in the defense response of citrus flavedo to postharvest pathogens, indicate that the yeast-induced oxidative response in fruit exocarp may be associated with the ability of specific yeast species to serve as biocontrol agents for the management of postharvest diseases. Effect of ROS on yeast cells was also studied. Pretreatment of the yeast, Candida oleophila, with 5 mM H₂O₂ for 30 min (sublethal) increased yeast tolerance to subsequent lethal levels of oxidative stress (50 mM H₂O₂), high temperature (40 °C), and low pH (pH 4). Suppression subtractive hybridization analysis was used to identify genes expressed in yeast in response to sublethal oxidative stress. Transcript levels were confirmed using semi quantitative reverse transcription-PCR. Seven antioxidant genes were up regulated. Pretreatment of the yeast antagonist Candida oleophila with glycine betaine (GB) increases oxidative stress tolerance in the microenvironment of apple wounds. ROS production is greater when yeast antagonists used as biocontrol agents are applied in the wounds. Compared to untreated control yeast cells, GB-treated cells recovered from the oxidative stress environment of apple wounds exhibited less accumulation of ROS and lower levels of oxidative damage to cellular proteins and lipids. Additionally, GB-treated yeast exhibited greater biocontrol activity against Penicillium expansum and Botrytis cinerea, and faster growth in wounds of apple fruits compared to untreated yeast. The expression of major antioxidant genes, including peroxisomal catalase, peroxiredoxin TSA1, and glutathione peroxidase was elevated in the yeast by GB treatment. A mild heat shock (HS) pretreatment (30 min at 40 1C) improved the tolerance of M. fructicola to subsequent high temperature (45 1C, 20–30 min) and oxidative stress (0.4 mol-¹) hydrogen peroxide, 20–60 min). HS-treated yeast cells showed less accumulation of reactive oxygen species (ROS) than non-treated cells in response to both stresses. Additionally, HS-treated yeast exhibited significantly greater (P≥0.0001) biocontrol activity against Penicillium expansum and a significantly faster (Po0.0001) growth rate in wounds of apple fruits stored at 25 1C compared with the performance of untreated yeast cells. Transcription of a trehalose-6-phosphate synthase gene (TPS1) was up regulated in response to HS and trehalose content also increased.