The antioxidant activity, as a consequence of the presence and polyphenols chemical structure, has lead their interest in the possible beneficial effects on foods health and beverages with high content in polyphenols. Antioxidants protect the body from free radicals, highly reactive molecules that can damage the body in the cellular level. This damage by free radicals can increase the risk to the cancer development, cardiovascular diseases and other degenerative diseases. The present work aim is to get cocoa seeds (Theobroma cacao) polyphenolic extracts and from Chuchuhuaso (Maytenus macrocarpa) cortex as a possible natural Amazonian antioxidant. The species were collected at the Research, Postgraduate and Amazonian Conservation Center, whose specimens were identified by the botanist Dr. David Neill and rested in the Ecuadorian Amazonian Herbarium. Polyphenolic activity was determined to hydroalcoholic extracts by Folin. Total polyphenolic concentration results on gallic acid in the cocoa (Teobroma cacao) extracts and chuchuhuaso (Maytenus laevis) cortex were 24,437 mg.mL-1 and 19,895, respectively. It is concluded that the two Amazonian species investigated provided relevant results in relation to the presence of total polyphenolic compounds, which allows preliminary prediction of a promising antioxidant activity. This preliminary study allowed to identify, for the first time, new polyphenols sources in promising plant species of the Ecuadorian Amazon region.

In a recent paper we have discussed the innovative and original concept the “squalenoylation” of nanoparticles. This method may be used in the nanoparticle-based formulation of a wide range of drug molecules (both hydrophilic and lipophilic). The "squalenoylation" approach is based on the covalent linkage between the squalene, a natural and biocompatible lipid belonging to the terpenoid family, and a drug, in order to increase its pharmacological efficacy. Fundamentally, the dynamically folded conformation of squalene triggers the resulting squalene-drug bioconjugates to self-assemble as nanoparticles of 100–300 nm. In general, these nanoparticles showed long blood circulation times after intravenous administration and improved pharmacological activity with reduced side effects and toxicity. This flexible and generic technique opens exciting perspectives in the drug delivery field.
Ref: Curr Top Med Chem 2017, https://www.ncbi.nlm.nih.gov/pubmed/28730957

Our recent review discusses the substantial cyclopentenyl fatty acid class of naturally occurring lipids. These compounds are historically important and have recently been shown to exhibit remarkable biological activity relevant to producing new antibiotic agents. Information about the history of cyclopentenyl fatty acids, their use in traditional and modern medicine, as well as biological activity, and methods for their synthesis are given. Please, see full reference: Almahli H.Cyclopentenyl Fatty Acids: History, Biological Activity and Synthesis.Curr Top Med Chem. 2017 Aug 21https://www.ncbi.nlm.nih.gov/pubmed/28828992

Active packaging is a packaging system that has incorporated additives and that interact directly with the food in order to prolong its quality and its useful life. Due to the bioindecomposability and toxicity of synthetic polymers and additives, the search for natural substances, which present more suitable characteristics for the production of active packages, such as chitosan, which is a naturally occurring polymer and flavonoids, increase, because they have low toxicity and activities antioxidant and antimicrobial. The purpose of this study to perform the interaction of flavonoids quercetin, rutin, quercitrin and artemetin with chitosan by molecular docking, aiming at the planning of new biodegradable and non-toxic active films. The molecular docking study was performed using Autodock 4.0. The three-dimensional structure of the chitosan was obtained through the PolySac3DB bank, while the flavonoid structures were acquired through PubChem. The results showed that the flavonoids quercetin, quercitrin and artemetin interacted attractively with chitosan. Quercetin was the flavonoid that interacted more stable, with an energy expenditure of -3.61 kcal / mol. The rutin was the only flavonoid, among those involved in the study, that did not interact attractively with chitosan, as its binding energy was 0.49 kcal / mol. It is observed that the interaction of rutin with chitosan is impaired due to its high level of torsion. It was observed that the flavonoids targets of this study, with the exception of rutin, interacted attractively with chitosan, suggesting that they are good candidates for additives for the production of active films.

In this report, the blood brain barrier (BBB) permeability prediction is carried out using a decision tree. A recently published data set of 497 compounds is selected to develop the tree model. The developed model shows an accuracy of 87.66% for training set; 86.09% in the 10-fold cross-validation procedure and 87.93% for the test set. Some structural explanation of how our model describe the passage of molecules through the BBB is given. Moreover, a comparison with other approaches is carried out showing good behaviour of our method. Finally, we can say that, the present results could represent a useful tools available and reproducible by all scientific community in the early stages of neuropharmaceutical drug discovery/development projects.

Vector-borne diseases are one of the important health problems in most tropical countries. Aedes aegypti is an important vector for transmission of dengue, yellow fever, chikungunya, arthritis, and Zika fever. According to the World Health Organization, it is estimated that Ae. aegypti causes 50 million infections and 25,000 deaths per year. The emerging scenario highlights that the eco-friendly and effective control measures for mosquito vectors is of crucial importance. One of the most effective vector control measures has been the use of larvicidal compounds however; this success was short lived due to development of resistance against them in many mosquito strains, ecological imbalance and undesirable effects on non-target organisms. For this reason, the aim of present study was to deduce a mathematical model to predict the larvicidal action of chemical compounds, based on their structure. A series of different compounds with experimental evidence of larvicidal activity were selected to develop a predictive model, using Multiple Linear Regression and a Genetic Algorithm for the selection of variables, implemented in the QSARINS software. The model was assessed and validated using the OECDs principles. The best model showed good value for the determination coefficient (R² = 0.752), and others parameters were appropriate for fitting (s = 0.278 and RMSE_tr= 0.261). The validation results confirmed that the model has good robustness (Q²_LOO=0.682) and stability (R²–Q²_LOO=0.070) with low correlation between the descriptors (K_XX=0.241), an excellent predictive power (R²_ext=0.834) and was product of a non-random correlation (R²_Yscr=0.100). The present model shows better parameters than the models reported earlier in the literature, using the same dataset, indicating that the proposed computational tools are more efficient in identifying novel larvicidal compounds against Ae. aegypti.

Psidium guayava essential oil (EO) from Ecuador was screened for its antiproliferative activity against three human colon carcinoma cell lines: HCT116 a human colon adenocrcinoma grade II, sensitive to 5-fluorouracil and oxaliplatin; CaCO2, a primary adenocarcinoma grade II; SW620, a highly resistant cell line deriving from a lymph-node mestastasis. Peripheral Blood Mononucleated Cells (PBMC) from a healthy donor buffy coat were utilized as healthy control cells. Cells were treated with increasing concentrations of P. guajava EO (40-80  µg/ml) dissolved in 0.25 DMSO and added to growth medium. 24 hours after cells were detached with trypsin and number of viable cells was determined by Tripan blue exclusion and/or or calcein-AM method, thus providing percentage of viable cells and rate of proliferation as well. Dose dependent antiproliferative and cytotoxic effects were observed, with a percentage of growth inhibition ranging from 40 to 80 %. 48h treatment did not increased effectiveness of the EO (probably because of a short half-life) Interestingly treating PBMC with 50µg/ml no anti-proliferative effects were observed, suggesting that this concentration, corresponding to IC 50 of this OE, did not lead evaluable toxicity to healthy cells such as PBMC. Further studies regarding chemical characterization and combination with commonly utilized anticancer drugs may be done as next step.

Nanoparticulate NiO and NiO/C composites with different carbon proportions have been prepared for anode application in lithium and sodium ion batteries. Structural characterization demonstrated the presence of metallic Ni in the composites. Morphological study revealed that the NiO and Ni nanoparticles were well dispersed in the matrix of amorphous carbon. The electrochemical study showed that the lithium ion batteries (LIBs) containing composites with carbon have promising electrochemical performances delivering specific discharge capacities of 550 mAh/g after operating for 100 cycles at 1C. These excellent results could be explained by the homogeneity of particle size and structure as well as the uniform distribution of NiO/Ni nanoparticles in the in situ generated amorphous carbon matrix. On the other hand, the sodium ion battery (NIB) with the NiO/C composite revealed a poor cycling stability. Post-mortem analyses revealed that this fact could be ascribed to the absence of a stable SEI or passivation layer upon cycling.

The synthesis of tetracarbonyl (pyrrolylimine) complexes of rhenium bearing chirality on the pyrrolyl ligands was reported. The reactivity of these compounds towards the substitution of one carbonyl ligand with triphenyl phosphine, tricyclohexyl phosphine and trimethyl phosphite was studied. The rhenium becoming a stereogenic center in that transformation, the resulting tricarbonyl species were obtained as mixtures of diastereomers, with diastereomeric excesses varying from 8 to 84%, according to the reaction conditions and the relative steric hindrances of the pyrrolylimine and the organophosphorus ligands.

In this work, a very useful and accurate procedure, based on the spectrophotometric method published by the American Public Health Association in the Standards Methods for the Examination of Water and Wastewater, was developed to determine cell density of Isochrysis galbana performing a single direct absorbance measurement in exponential phase of growth, which is the desirable operating mode for any microalgae production plant. Thus, Isochrysis galbana was cultured in serial batch cultures from a larger scale fed-batch culture. The growth performance of this species of microalgae under laboratory conditions was analysed by spectrophotometry at different wavelengths and cell counting in a haemocytometer (Neubauer chamber) showing that doubling times and cell death increased with increasing initial cell density. Besides, it was demonstrated that the absorbance of these cultures followed a linear trend as a function of time and cell density during the exponential phase of growth, results in which the developed direct method is based on.

https://www.ucv.es/investigacion/publicaciones/catalogo-de-revistas/revista-nereis (NEREIS Nº9)