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Submitted by Raquel Sabará da Cruz null (raqsabara@hotmail.com) on 2016-03-21T22:33:50Z No. of bitstreams: 1 dissertação versão final-impressão.pdf: 2574095 bytes, checksum: 8540d453330bcae116046e55b480b86b (MD5) / Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2016-03-22T19:26:18Z (GMT) No. of bitstreams: 1 cruz_rs_me_araiq_par.pdf: 1393236 bytes, checksum: fb9a7d96afc03bc23ad50d07330e227c (MD5) / Made available in DSpace on 2016-03-22T19:26:18Z (GMT). No. of bitstreams: 1 cruz_rs_me_araiq_par.pdf: 1393236 bytes, checksum: fb9a7d96afc03bc23ad50d07330e227c (MD5) Previous issue date: 2016-03-04 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Beta-aminoésteres/ácidos quirais enantiomericamente puros são blocos construtores quirais economicamente importantes para a indústria farmacêutica, de química fina, e agroquímica. As transaminases, também conhecidas como aminotransferases têm emergido como uma importante classe de enzimas com grande potencial na síntese enantiosseletiva desses compostos. Neste trabalho foi avaliada a reatividade de omega-transaminases frente a beta-cetoésteres arílicos (benzoilacetato de etila) e alquílicos (acetoacetato de etila) visando à síntese enantiosseletiva de beta-aminoésteres/ácidos. As enzimas utilizadas neste trabalho foram produzidas no laboratório a partir de plasmídeos contendo genes que codificam omega-transaminases (R) e (S)-seletivas provenientes de diferentes micro-organismos. Essas enzimas juntamente com uma enzima comercial (S)-seletiva foram empregadas em reações de aminação assimétrica utilizando substratos beta-cetoésteres, e na resolução cinética da (R,S)-feniletilamina. Parâmetros como concentração de enzima:substrato, compostos doadores de grupo amino, temperatura e pH foram avaliados visando à otimização dos rendimentos e enantiosseletividade. As enzimas produzidas apresentaram excelentes conversões (> 99 %) nas reações de síntese assimétrica e elevados excessos enantioméricos (> 99 %) em praticamente todas as reações de resolução cinética nas quais o acetoacetato de etila foi empregado como substrato. Por outro lado, nas reações onde o benzoilacetato de etila foi empregado como aceptor de amina, não se observou a formação do produto de interesse. / Optically pure beta-amino esters/ acids constitute economically important chiral building blocks for the pharmaceutical, fine chemical and agrochemical industries. Transaminases, also known as aminotransferases have emerged as an important class of enzymes with great potential in the enantioselective synthesis of these compounds. In this work, was evaluated the reactivity of omega-transaminase against aryl (ethyl benzoylacetate) and alkyl (ethyl acetoacetate) beta-keto esters for the enantioselective synthesis of beta-amino esters/acids. The enzymes used in this work were produced in the laboratory from plasmids containing genes encoding (R) and (S)-selective omega-transaminases from different micro-organisms. These enzymes along with a (S)-selective commercial enzyme were employed in the asymmetric amination reactions using beta-keto esters substrates and kinetic resolution of (R,S)-phenylethylamine. Parameters such as concentration of enzyme:substrate, amino group donors, temperature and pH were evaluated aiming to optimize yields and enantioselectivity. The enzymes produced showed excellent conversion (> 99%) in the asymmetric synthesis reactions and high enantiomeric excess (> 99%) in practically all kinetic resolution reactions in which ethyl acetoacetate was used as substrate. On the other hand, in reactions where the ethyl benzoylacetate was used as amino acceptor, was not observed the formation of the product of interest. / CNPq: 132685/2014-0

Orientador: Anita Jocelyne Marsaioli / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Quimica / Made available in DSpace on 2018-08-07T11:17:14Z (GMT). No. of bitstreams: 1 Pinheiro_Lucimar_D.pdf: 3524874 bytes, checksum: 8abbae35ad9ff5f54218f4dac80a18bf (MD5) Previous issue date: 2006 / Resumo: A utilização de enzimas para a transformação de compostos orgânicos é cada vez mais utilizada como alternativa à síntese clássica. As enzimas são utilizadas como biocatalisadores para as sínteses in vitro de compostos assimétricos uma vez que elas são intrinsicamente quirais e apresentam alta eficiência catalítica. Diante da biodiversidade de microrganismos existentes na natureza e da necessidade de descobrir novos biocatalisadores para as sínteses de blocos de construções quirais e de produtos químicos de alto valor agregado, esta tese teve como objetivos a avaliação enzimática de células microbianas íntegras, o isolamento e a identificação de compostos enantiomericamente puros obtidos através da ação enzimática de oxidorredutases. Inicialmente, a avaliação da presença de Baeyer-Villiger monooxigenases em 12 espécies de fungos através de biocatálise convencional levou a produção de (R)-(+)-5-metil-e-caprolactona (1b), produzida pelos fungos Aspergillus oryzae CCT 0975 e Geotricum candidum CCT 1205 em excelentes conversões (ambas 98%) e excessos enantioméricos (96% e 91%), respectivamente. Na etapa seguinte foi desenvolvida uma metodologia alternativa a biocatálise convencional, denominada "multibiorreações", objetivando uma triagem mais rápida e eficiente. A metodologia foi aplicada na detecção de atividade de monooxigenase permitindo um aumento no conhecimento do perfil de seletividade dos substratos analisados. A ação enzimática das células íntegras de Trichosporum cutaneum CCT 1903 resultou na redução de metilcicloexanonas orto- e para-substituídas (1 e 6) e na oxidação da cis-jasmona (8). Posteriormente realizou-se o isolamento, identificação, determinação dos excessos enantioméricos, determinação das configurações relativas e absolutas dos produtos obtidos a partir da oxidação da cis-jasmona (8): (7S,8R)-epoxijasmona, 12 (92% e.e.), 7,8-diidróxijasmona, 13 (53% e.e.) e (4S)-hidroxijasmona (86% e.e.). Nesta etapa, a determinação do perfil de seletividade de T. cutaneum CCT 1903 foi avaliado frente a 14 substratos contendo ligações duplas olefínicas (24-37). A atividade de monooxigenase foi verificada sobre os seguintes monoterpenos monocíclicos: (R)-(-)-carvona (25), a- e b- iononas (26 e 27) e (R)-(+)-limoneno (32). As biotransformações destes compostos de fragrâncias levaram às sínteses de: (1S,2R,4R)-neoisodiidrocarveol (41), (6R)-isoprenil- (3R)-metil-2-oxo-oxepanona (42), ácido-(3R)-isopropenil-6-oxo-heptanóico (43), 2,3-epóxi-(5R)-isopropenil-2-metilcicloexanol (44), 4-oxo-7,8-diidro-b-ionona (50), a-homociclogeraniol (51), limoneno-1,2-diol (54) e (+)-(4R)-p-1-menteno-8,9-diol (55), os quais foram identificados espectroscopicamente (RMN de H e C, H e H gCOSY, H e C HSQC, H e C gHMBC). Finalmente, foi realizado um estudo das atividades enzimáticas para os fungos CCT 5632, Rhyzopus oryzae CCT 1022 e a levedura AMA 7, utilizando a metodologia de multibiorreações e reações de biotransformações convencionais (substratos 8, 25-27 e 32). Uma atividade oxidorredutase foi detectada em AMA7 e R. oryzae CCT 1022. A levedura AMA7 produziu a: 7,8-epoxijasmona (12), 7,8-diidroxijasmona (13), 4- hidroxijasmona (14) e a diidrocarvona (45), enquanto que R. oryzae CCT 1022 produziu o composto 14 e o neoisodiidrocarveol (41). O fungo 5632 também apresentou atividade monooxigenase verificada a partir da formação da 4-oxo-7,8-diidro-b-ionona (50) / Abstract: The utilization of enzymes for organic compound transformations is an alternative to classical syntheses. Enzymes are used as biocatalysts for the syntheses in vitro of asymmetric compounds because they are intrinsically chiral and result in high catalytic efficiency. In front of the biodiversity of existing microorganisms in Nature and of the necessity to discover new biocatalysts for the syntheses of blocks of chiral constructions and of chemical products with high added value, this thesis aimed at enzymatic evaluation of oxidoreductase from microbial whole cells and their application of the production of enantiomerically pure compounds. First of all, Baeyer-Villiger monooxygenase (BVMO) activity was monitored using traditional biocatalytic methods. Bioprospection in 14 fungi resulted in the detection of cyclohexanone BVMO in Aspergillus oryzae CCT 0975 and Geotrichium candidum CCT 1205. The lactone (R)-(+)-1b was obtained in high enantiomeric excesses (96% and 91%, respectively) and conversion (98%). Searching for rapid screening method, multibioreaction methodology was implemented and applied to the detection of monooxigenase activity, which increased n times the amount of evaluated microorganisms per unit of time, where n is the number of added substrates. Trichosporum cutaneum CCT 1903 produced outstanding results, reducing the ortho- and para-substituted (1 and 6) methyl-cyclohexanones and oxidizing cis-jasmone (8). After isolation, identification and determination of the enantiomeric excess, the relative and absolute configuration of the cis-jasmone bioproducts were: (7S,8R)-epoxyjasmone, 12 (e.e. 92%), 7,8-dihydroxyjasmone, 13 (e.e. 53%) and (4S)-hydroxyjasmone, 14 (e.e. 86%). The enantioselectivity and substrate specificity of alkene monooxygenase in T. cutaneum CCT 1903 was further investigated using 14 substrates (24-37), applying the multibioreaction approach. Monooxygenase activity was detected in (R)-(-)-carvone, a- and b-ionones and (R)-(+)-limonene. Batch reactions of these fragrance compounds produced: (1S,2R,4R)- neoisodihydrocarveol (41), (6R)-isoprenyl-(3R)-methyl-2-oxo-oxepanone (42), (3R)- isopropenyl-6-oxoheptanoic acid (43), 2,3-epoxy-(5R)-isopropenyl-2-methylcyclohexenol (44), 4-oxo-7,8-dihydro-b-ionone (50), a-homo-cyclogeraniol (51), (R)-(+)-limonene-1,2-diol (54) and uroterpenol (55) as pure samples for spectroscopic identification (H and C NMR, H and H gCOSY, H and C HSQC, H and C gHMBC). Oxidoreductase activity was monitored using multibioreaction methodology and traditional biocatalytic methods with the fungi CCT 5632, Rhyzopus oryzae CCT 1022 and the yeast AMA 7 (substrates 8, 25-27 and 32). Thus AMA7 produced epoxyjasmone (12), 7,8- dihydroxyjasmone (13), hydroxyjasmone (14) and dihydrocarvone (45), while that R. oryzae CCT 1022 produced 14 and neoisodihydrocarveol (41). The fungus 5632 also presented monooxygenase activity confirmed through formation from 4-oxo-7,8-dihydro-b- ionone (50) / Doutorado / Quimica Organica / Doutor em Ciências

O primeiro capítulo desta tese é dedicado aos estudos que visaram à aplicação da biocatálise na síntese de γ-butirolactonas quirais. Inicialmente investigou-se a preparação de fenilseleno-γ-butirolactonas quirais, através da resolução cinética enzimática dos fenilseleno-γ-hidróxi ésteres correspondentes. Através desta estratégia, ambos os enantiômeros da fenilseleno-γ-butirolactona foram preparados em excessos enantioméricos razoáveis. Ainda no primeiro capítulo é demonstrado o potencial sintético do (R)-3-(5-oxotetraidro-2-furanil)-propanoato de benzila, obtido através de uma enantiolactonização catalisada por PPL na etapa chave. Este intermediário quiral foi utilizado com sucesso na síntese enantiosseletiva da (R)- e da (S)-y-jasmolactona, aromatizantes de interesse industrial, além de ambos enantiômeros da (7Z)-7,15-hexadecadien-4-oIida, feromônio sexual da \"Yellowish Elongate Chafer, Heptophy/a picea\" . A segunda parte deste trabalho foi efetuada na Universidade da Califórnia, EUA, sob a orientação do professor Bruce H. Lipshutz, durante o período de novembro de 2003 a outubro de 2004. Dois novos reagentes foram desenvolvidos e aplicados com sucesso na preparação estereosseletiva de polienos conjugados com estrutura análoga a da vitamina A . / The first chapter of this thesis is dedicated to the studies on the application of biocatalysis in the synthesis of chiral γ-butyrolactones. We started investigating the preparation of phenylselanyl-γ-butyrolactones through the kinetic enzymatic resolution of the corresponding phenylselanyl-γ-hydroxyesters. By using this strategy both enantiomers of phenylselanyl-γ-butyrolactone were prepared in reasonable enantiomeric excesses . In the first chapter is also demonstrated the synthetic potential of benzyl 3[(R)-tetrahydro-5-oxofuran-2-yl] propanoate, obtained through a PPL catalyzed enantiolactonization in the key step. This chiral intermediate was successfully applied in the enantioselective synthesis of (R)- and (S)-γ-jasmolactone, flavors that find industrial use, and both enantiomers of (7Z)-7,15-hexadecadien-4-olide, the sex pheromone of Yellowish Elongate Chafer, Heptophy/a picea. The second part of this work was carried out at University of California, USA, between November 2003 and October 2004, under supervision of Professor Bruce H. Lipshutz. Two new reagents were developed and successfully applied in the stereoselective synthesis of conjugated polienes analogs to vitamin A .

Enantiomerically pure amines have a variety of industrial applications. They are valuable components within the pharmaceutical and agrochemical industry, resolving agents for separation of racemic mixtures by dimeric salt formation and ligands for transition metal catalysts and chemocatalysts. Biocatalysis is increasingly seen as the method of choice for the synthesis of chiral amines. New commercial enzymes being readily available and new screening/evolution technologies allow for enzyme optimisation towards a set of required conditions for chiral amine synthesis. Transaminases are a class of pyridoxal 5’-phosphate (PLP) dependant enzymes that catalyse the reversible transfer of ammonia from an amine donor (e.g. alanine) to a keto acceptor (e.g. acetophenone), allowing the potential for asymmetric methodologies. Transaminases are already well established for the industrial production of α-amino acids and now that research scientists have dealt with some of the problems with equilibrium and substrate/product inhibition, they are being investigated for the industrial application of chiral amines. A multi-enzyme kinetic assay has been utilised for characterisation of newly identified transaminase enzymes in solution phase. Identified transaminases that showed desirable characteristics were cloned and expressed and utilised in the synthesis of amines of interest to industry. Dual enzyme cascade reactions utilising transaminases and either galactose oxidase from Fusarium sp. or monoamine oxidase from Aspergillus niger were used to produce a number of primary and secondary amines in high e.e. and conversion.

Yes / For the development of applications and novel uses for peptide nanostructures, robust routes for their surface functionalization, that ideally do not interfere with their self‐assembly properties, are required. Many existing methods rely on covalent functionalization, where building blocks are appended with functional groups, either pre‐ or post‐assembly. A facile supramolecular approach is demonstrated for the formation of functionalized nanofibers by combining the advantages of biocatalytic self‐assembly and surfactant/gelator co‐assembly. This is achieved by enzymatically triggered reconfiguration of free flowing micellar aggregates of pre‐gelators and functional surfactants to form nanofibers that incorporate and display the surfactants’ functionality at the surface. Furthermore, by varying enzyme concentration, the gel stiffness and supramolecular organization of building blocks can be varied. / FP7 Marie Curie Actions of the European Commission. Grant Number: 289723; EPSRC; HFSP; ERC; Leverhulme Trust

Biocatalysis is becoming an increasingly attractive alternative to more traditional chemical transformations for use in pharmaceutical and industrial applications. This interest is primarily a consequence of the high regio-, stereo- and enantioselectivity that is associated with enzyme catalysed reactions. However, the proliferation of such techniques has been limited due to the dependence of enzyme activity upon the presence of redox cofactors, which are typically expensive and must be used in conjunction with efficient regeneration systems. Whilst numerous methods have been described, of particular potential are those that employ exogenous photosensitisers as a means of generating reducing equivalents to promote catalytic turnover. In this study the potential of transition metal complexes as photosensitisers towards the development of light-driven biocatalytic systems is evaluated. Use of such compounds gives great scope towards fine-tuning the spectral and redox properties of the sensitisers with the aim of optimising catalytic efficiency. Detailed herein is an extensive study towards the synthesis and characterisation of a range of ruthenium(II) and iridium(III) coordination compounds. Using NMR, UV-vis, and electrochemical techniques, all complexes were fully characterised and the origins of the photophysical properties further investigated using time-dependent density functional theory (TD-DFT) calculations. A series of ruthenium compounds were synthesised containing the bis(2,2′-bipyrazyl)ruthenium(II) moiety, investigating the impact of changes made to the functionality of the ancillary ligand upon the overall properties of the complex. New synthetic procedures have been developed towards the preparation of both 2,2′-bipyrazine and the related complexes, exhibiting significant benefits over previously established methods. Through manipulating the electron density of the ancillary ligand it is shown that the redox properties may be effectively tuned upon inducing changes in the energy of the metal-based HOMO. The utilisation of cyclometalated iridium(III) complexes in aqueous systems has been limited due to a poor water solubility that is typically associated with these compounds. Herein it is demonstrated that this issue may be effectively circumvented on inclusion of the positively charged pyridinium moiety. Upon incorporation of this functional group into either the cyclometalating or ancillary ligands, two distinct series of compounds were successfully prepared. Complexes of the substituted quaterpyridinium ligands possess complicated UV-vis spectra that exhibit low intensity absorbance up to 650 nm. A number of monoquaternised bipyridinium compounds were also utilised as pyridine derived N-heterocyclic carbene cyclometalating ligands, to afford a range of complexes with unique redox properties. The prepared photosensitisers were subsequently used to induce catalytic turnover in light-driven biocatalytic systems utilising the flavin dependent oxidoreductase enzymes, pentaerythritol tetranitrate reductase (PETNR) and the thermophilic old yellow enzyme (TOYE). Through an extensive investigation, optimal reaction conditions have been identified and a mechanism of electron transfer proposed. These systems were successfully implemented in the reduction of a broad range of substrates under both aqueous and biphasic conditions, delivering yields and enantiomeric excesses comparable to those obtained utilising an enzyme coupled regeneration system. This study clearly demonstrates that transition metal complexes are excellent candidates in developing practical light-driven biocatalytic systems. It is expected that, with further investigation, this approach can be readily expanded to incorporate a variety of applications and provide an effective alternative to the use of costly redox cofactors and a reliance upon complex regeneration techniques.

Biocatalysis is an ever evolving field that uses enzymes or microorganisms for chemical synthesis. By utilizing enzymes that generally have evolved for specific reactions under mild conditions and temperatures, biocatalysis can be a more environmentally friendly option compared to traditional chemistry. Amide-type chemistries are important and bond formation avoiding poor atom economy is of high priority in organic chemistry. Biocatalysis could potentially be a solution but restricted substrate scope is a limitation. Esterases/lipases usually display broad substrate scope and catalytic promiscuity but are poor at hydrolyzing amides compared to amidases/proteases. The difference between the two enzyme classes is hypothesized to reside in one key hydrogen bond present in amidases, which facilitates the transition state for nitrogen inversion during catalysis. In this thesis the work has been focused on introducing a stabilizing hydrogen bond acceptor in esterases, mimicking that found in amidases, to develop better enzymatic catalysts for amide-based chemistries. By two strategies, side-chain or water interaction, variants were created in three esterases that displayed up to 210-times increased relative amidase specificity compared to the wild type. The best variant displayed reduced activation enthalpy corresponding to a weak hydrogen bond. The results show an estimated lower limit on how much the hydrogen bond can be worth to catalysis. MsAcT catalyze kinetically controlled N-acylations in water. An enzymatic one-pot one-step cascade was developed for the formation of amides from aldehydes in water that gave 97% conversion. In addition, engineered variants of MsAcT with increased substrate scope could synthesize an amide in water with 81% conversion, where the wild type gave no conversion. Moreover, variants of MsAcT displayed up to 32-fold change in specificity towards amide synthesis and a switch in reaction preference favoring amide over ester synthesis. / <p>QC 20161125</p>

Whole-cell biocatalysts are preferred in many biocatalysis applications. However, cell envelope often represents a formidable permeability barrier. As a result, reactions catalyzed by whole-cells are reportedly orders of magnitude slower than those of by their free enzyme counterparts. The present research addresses this critical issue by using membrane engineering approaches. Two E. coli strains with genetically altered outer membrane structures were used in the study, a lipopolysaccarides (LPS) mutant SM101 and a Braun's lipoprotein mutant E609L. The effects of outer membrane mutation on the permeability of substrates differing substantially in size and hydrophobicity were investigated by combining the mutant cells with model enzymes. The reduction of the outer membrane permeability barrier by these mutations led to significant accelerations (2 to 14 fold) in reaction rates of all whole-cell catalyzed reactions investigated. In the case of tetrapeptide, LPS mutation of the outer membrane can render the outer membrane completely permeable to substrate, a barrier-less condition that maximizes the reaction rate. For reaction rates of toluene dioxygenase (TDO)-catalyzed reactions, a dramatic increase of up to six fold was observed with the lipoprotein mutant for each of the three small, hydrophobic substrates tested. Mutations in either the LPS or in the Braun's lipoprotein are effective for accelerating reactions with UDP-glucose, resulting in a striking acceleration (up to 14 fold) of reaction rate. The magnitude of reaction rate acceleration was found to be dependent upon the substrate concentrations, the enzyme expression level, and on the nature of the mutations and substrates. In addition, the mutations have been demonstrated to be far more superior to common permeabilization procedures like freeze-thaw (FT) or treatment with the chelating agent EDTA (ethylene diamine tetraacetic acid). Importantly, lipoprotein mutant E609L exhibited a normal growth rate and expressed the recombinant multi-component enzyme as well as the isogenic parent. The exact nature of lpp lipoprotein mutation in E609L was further studied and deletion of lpp was successfully introduced into E. coli strain with different genetic background for whole-cell biocatalysis applications. An example was provided by introducing an lpp deletion into an E. coli O44K74 strain to achieve a higher yield for L-carnitine production. This research and the results outlined in this dissertation demonstrate a valid strategy for addressing permeability issues in whole-cell biocatalysis. The work also highlights a need for accessing substrate permeabilities in biocatalysis research and development.

Face à l’apparition croissante de troubles pigmentaires liés à l’exposition aux UV, le développement de nouveaux actifs blanchissants représente un enjeu majeur pour l’industrie cosmétique. De plus en plus de consommateurs s’orientent vers des produits eco-responsables, il devient urgent de développer de nouvelles méthodes de biocatalyse pour accéder à des antipigmentants. Certains glycosides, comme l’arbutine présentent des propriétés blanchissantes qui restent toutefois limitées face à l’hydrolyse rapide de la liaison O-glycosidique. L’enjeu du projet consiste à synthétiser des analogues de cette molécule en série thioglycosidique. En effet, cette liaison permet une plus grande stabilité vis à vis de l’hydrolyse. La mutation d’une glycosidase native issue de dictyoglomus thermophilum a permis d’accéder à une thioglycoligase. Cette dernière permet d’obtenir par catalyse enzymatique des analogues de l’arbutine. Six composés en série S- et O-glycosidique ont pu être synthétisés et testés en tant qu’agents dépigmentants. La méthodologie de synthèse a ensuite été appliquée pour l’obtention de thioglycolipides. Ces molécules sont connues pour leurs propriétés hydrogélifiantes permettant d’accéder à des matériaux thermoreversibles. Cinq molécules ont été identifiées en tant qu’agents hydrogélifiants. Les propriétés rhéologiques, thermiques et structurales ont été caractérisées mettant en évidence des différences significatives parmi les composés. Enfin les résultats préliminaires sur la formulation d’un produit à la fois antipigmentant et texturant s’avèrent prometteurs pour la validation d’un concept de matériau intelligent pour l’industrie cosmétique. / Considering the increasing appearance of pigmentation disorders caused by UV exposure, the development of new whitening agents is a major challenge for the cosmetics industry. Consumers are turning to ecoresponsible products, it is urgent to develop new methods of biocatalysis for the access to new depigmenting agents. Some glycosides, such as arbutin, have whitening properties which are still limited because of therapid hydrolysis of the O-glycosidic bond. The challenge of this project is synthesize analogues of this molecule in thioglycoside series. Endeed, this bond allows a greater stability against the hydrolysis. The mutation of anative glycosidase to dictyoglomus thermophilum gives access to a thioglycoligase. This makes possible the enzymatic synthesis of arbutine analogues. Six molécules were synthesized and tested as depigmenting agents. The synthesis methodology was then applied to the preparation of thioglycolipids. These moleculesare known for their hydrogellating properties allowing access to thermoreversible materials. Five molecules have been identified as hydrogellating agents. The rheological, thermal and structural properties have been characterized and showed significant differences depending of the compound structure. Lastly, the preliminary results on the formulation of a product that is both antipigmenting and texturizing are promising for the validation of an smart material concept for the cosmetic industry.