López Nicolás, José Manuel

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López Nicolás, José Manuel

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López Nicolás, José Manuel

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Universidad de Murcia. Departamento de Bioquímica y Biología MolecularA

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Reactividad de lipoxigenasas vegetales frente a micelas mixtas, complejos de ciclodextrinas y agregados de linoleato cálcico / José Manuel López Nicolás ; dirección Francisco García Carmona, Roque Bru Martinez.
(Murcia : Universidad de Murcia, Facultad de Química,, 1997) López Nicolás, José Manuel
Open Access
Prácticas. Técnicas Instrumentales: HPLC y Refractometría
(2018-09-27) Gandía Herrero, Fernando; López Nicolás, José Manuel; Facultad de Biología; Departamento de Bioquímica y Biología Molecular A
Material docente utilizado para desarrollar clases prácticas de técnicas instrumentales, en asignaturas de Ciencias Biológicas.
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Study of oxyresveratrol complexes with insoluble cyclodextrin based nanosponges: Developing a novel way to obtain their complexation constants and application in an anticancer study
(Elsevier, 2019-12-17) Kumar Dhakarb, Nilesh; Bessonec, Federica; Musso, Giorgia; Cavallic, Roberta; Dianzanic, Chiara; Matencio Durán, Adrián; López Nicolás, José Manuel; García Carmona, Francisco; Bioquímica y Biología Molecular A
The complexation of the bioactive compound oxyresveratrol (OXY) with a polymer called cyclodextrin-based nanosponge (CD-NS) and its application was studied.A new methodology is used to calculate, an apparent inclusion complex constant (KFapp) between a ligand and CD-NSs. Moreover, the KFapp of resveratrol was also evaluated and compared. The complex of OXY with the nanosponge β-CDI 1:4, was studied in vitro using DSC, TGA and FTIR techniques and its drug loading and release behavior were studied. An in vitro digestion showed higher protection of OXY complexed than free OXY. The bioactivity enhancing capacity of OXY was also studied against prostate (PC-3) and colon (HT-29 and HCT-116) cancer cell lines, where it showed stronger cell viability inhibition than the free drug. The findings as a whole represent a new opportunity for studying the complexation of drugs in CD-NSs and the use of oxyresveratrol as an ingredient in nutraceutical products.
Open Access
Stilbenes: Characterization, bioactivity, encapsulation and structural modifications. A review of their current limitations and promising approaches
(Taylor and Francis Group, 2022-03-02) Navarro Orcajada, Silvia; Vidal Sánchez, Francisco José; Albadelejo Maricó, Lorena; Matencio Durán, Adrián; Conesa Valverde, Irene; López Nicolás, José Manuel; Vidal Sánchez, Francisco José; García Carmona, Francisco; Bioquímica y Biología Molecular A
Stilbenes are phenolic compounds naturally synthesized as secondary metabolites by the shikimate pathway in plants. Research on them has increased in recent years due to their therapeutic potential as antioxidant, antimicrobial, anti-inflammatory, anticancer, cardioprotective and anti-obesity agents. Amongst them, resveratrol has attracted the most attention, although there are other natural and synthesized stilbenes with enhanced properties. However, stilbenes have some physicochemical and pharmacokinetic problems that need to be overcome before considering their applications. Human clinical evidence of their bioactivity is still controversial due to this fact and hence, exhaustive basis science on stilbenes is needed before applied science. This review gathers the main physicochemical and biological properties of natural stilbenes, establishes structure-activity relationships among them, emphasizing the current problems that limit their applications and presenting some promising approaches to overcome these issues: the encapsulation in different agents and the structural modification to obtain novel stilbenes with better features. The bioactivity of stilbenes should move from promising to evident.
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Applications of cyclodextrins in food science. A Review
(Elsevier, 2020-08-25) Matencio Durán, Adrián; Navarro Orcajada, Silvia; López Nicolás, José Manuel; García Carmona, Francisco; Bioquímica y Biología Molecular A; Facultad de Biología
Background: The food industry is constantly attempting to develop better products that will have a positive effect on health (commonly known as functional foods). In this respect, cyclodextrins (CDs) could be of interest because they are tasteless, non-caloric and odourless molecules with several valuable characteristics, such as a capacity to separate chiral compounds and solubilize or stabilize bioactive compounds (BaC). Scope and approach: This review represents a revision of the state-of-the-art of CDs and their uses in the food industry. Key findings and conclusions: We analysed their metabolism and regulatory aspects of current applications of CDs: as carriers, for removing components, to produce or extract BaC, their use as nanosensors or in food packaging. We study how inclusion complexed are formed referring to the most common techniques and parameters Moreover, how inclusion complexes are formed will be studied with reference to the most common techniques and parameters. In conclusion, their applications in the food and other industries will increase in the coming years without a doubt.
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Comparative study of the antioxidant capacity of four stilbenes using ORAC, ABTS+, and FRAP Techniques
(Springer, 2017-03-17) Rodríguez-Bonilla, Pilar; Matencio Durán, Adrián; Gandía Herrero, Fernando; López Nicolás, José Manuel; García Carmona, Francisco; Bioquímica y Biología Molecular "A"
Researchers use several different analytical techniques, such as ORAC, ABTS·+, or FRAP, for measuring the antioxidant capacity of bioactive compounds. However, many authors do not take into account that these three techniques have different objectives. This contribution reports on the use of two types of tests to evaluate the antioxidant activity of four stilbene tests based first on the hydrogen atom transfer reaction (ORAC method) and the second on the single electron transfer reaction (ABTS·+ and FRAP assays). For the ORAC assay, the greatest antioxidant activity was shown by resveratrol, followed by oxyresveratrol, pterostilbene, and pinosylvin, while in the ABTS.+ assay, the highest antioxidant capacity was presented by oxyresveratrol, followed by resveratrol, pinosylvin, and finally pterostilbene. In the FRAP assay, the reducing activity shown by all the stilbenes was below that obtained for trolox. The role of phenolic hydroxyl groups was studied. The technique used should be selected taking into account the objectives and the conditions of the medium.
Open Access
Comunicaciones Orales.-Estudio de la nanoencapsulación molecular del ácido Ruménico con diferentes tipos de ciclodextrinas.
(2020-05-28) García Hernández Gil, Carlos J.; Matencio Durán, Adrián; López Nicolás, José Manuel; García Carmona, Francisco; Facultades, Departamentos, Servicios y Escuelas::Departamentos de la UMU::Bioquímica y Biología Molecular A
Open Access
A way to increase the bioaccesibility and photostability of roflumilast, a COPD treatment, by cyclodextrin monomers
(MDPI, 2019-05-04) Matencio Durán, Adrián; López Nicolás, José Manuel; García Carmona, Francisco; Hernández García, Samanta; Bioquímica y Biología Molecular A; Facultad de Biología
Roflumilast is an orally available inhibitor of phosphodiesterase (PDE) type 4, which is widely used in chronic obstructive pulmonary diseases. However, it has low solubility and adverse effects include diarrhea and nausea. Since its solubilization may improve treatment and, dismissing any adverse effects, its interaction with cyclodextrins (CDs) was studied. The Higuchi-Connors method was used to determine the complexation constant with different CDs, pH values and temperatures. Molecular docking was used to predict interaction between the complexes. An in vitro digestion experiment was carried out to test roflumilast protection. Finally, the photostability of the complex was evaluated. The complex formed with β-CD had the highest K11 value (646 ± 34 M−1), although this value decreased with increasing temperature. Similarly, K11 decreased as the pH increased. In vitro digestion showed that CDs protect the drug during digestion and even improve its bioaccessibility. Finally, CDs reduced the drug’s extreme photosensitivity, originating a fluorescence signal, which is described for first time. The kinetic parameters of the reaction were obtained. This study not only completes the complexation study of roflumilast-CD, but also points to the need to protect roflumilast from light, suggesting that tablets containing the drug might be reformulated.
Open Access
The inclusion complex of oxyresveratrol in modified cyclodextrins: a thermodynamic, structural, physicochemical, fluorescent and computational study
(Elsevier, 2017-04-06) Matencio Durán, Adrián; López Nicolás, José Manuel; García Carmona, Francisco; Bioquímica y Biología Molecular A; Facultad de Biología
The interaction between oxyresveratrol (a type of stilbene with high biological activity) and modified cyclodextrins (CDs) was studied. Using HPLC-RP, was seen to form a 1:1 complex with all the CDs tested. The best CD in this respect was MβCD (KF = 606.65 ± 30.18 M−1), the complexation showing a strong dependence on pH and temperature: The complexation constant (KF) decreased as the pH and temperature increased. The thermodynamic parameters studied (ΔH°, ΔS° and ΔG°) showed negative entropy, enthalpy and Gibbs free energy change at 25 °C. In addition, fluorescence signal of oxyresveratrol increased when MβCD was added. The oxyresveratrol emission and excitation spectra were obtained for first time. A 1H NMR was carried out to study the structure of the complex and, DSC studied demonstrated the complexation. A computational study by molecular docking was made to complement the structural study.
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Nanoparticles of betalamic acid derivatives with cyclodextrins. Physicochemistry, production characterization and stability
(Elsevier, 2020-07-14) Guerrero Rubio, Alejandra; Matencio Durán, Adrián; Gandía Herrero, Fernando; López Nicolás, José Manuel; García Carmona, Francisco; Bioquímica y Biología Molecular A
The use of betalains as bioactive compounds has been widely investigated. However, their use as a functional food requires a more exhaustive study because of their photosensitivity and poor stability. For this reason, this works studies the stabilization of two highly bioactive betalain derivatives, phenylethylamine-betaxanthin (Ph- Bx) and indoline-betacyanin (In-Bc) by nanoencapsulation in natural a modified cyclodextrins (CDs). Methyl- β-CD (Mβ-CD) showed the best results for Ph-Bx while Hydroxypropyl-β-CD (HPβ-CD) was better in the case of In- Bc. In addition, the effect of pH and temperature on encapsulation was studied finding that the encapsulation constant (KF) value increased as the pH decreased in the case of Ph-Bx but not in the case of In-Bc. The KF decreased as the temperatures increased. The thermodynamic parameters, ΔH◦, ΔS◦ and ΔG◦, were also calculated. Molecular docking provided further insight into how the different interactions influenced the encapsulation constant. The results show that the presence of CDs during the biotechnological synthesis of Ph-Bx and In- Bc increased production by 51 and 26%, respectively, and also increased the stability of both derivatives. This study represents a first step towards increasing the production of this type of compound for introduction into functional foods.