Augusto Lopes Souto’s research while affiliated with Federal University of Paraíba and other places

Introduction The prevalence of hypertension and obesity are a worldwide concern. Objetives Assess the metabolites profile after intervention with mixed dietary fiber in overweight and obese normotensive women. Methods This is a randomized double blind placebo-controlled study. Through a simple randomization process, two groups were allocated, with eleven women (group 1) receiving 12 g of mixed dietary fiber and thirteen women (group 2) receiving 12 g of placebo (corn starch) for eight weeks. Anthropometric and biochemical tests and lifestyle were analyzed. As for evaluation metabolomics, used a ¹H NMR. The data matrix generated 96 samples and 225 variables, which was exported in the ASCII format for the “The Unscrumbler” statistics software (version 9.7, CAMO Process). Results After the intervention with mixed dietary fiber, significant differences were observed between the main types of metabolites, referring to the increase in the relative peak areas of in three HDL metabolites 4.94 ppm (0.0086*), HDL 1.28 ppm (0 .0337*), HDL 0.88 ppm (0.0224*) and an α-glucose metabolite 4.90 ppm (0.0106) and the reduction in systolic blood pressure (SBP) (0.0292*) of 7 mmHg in the reference range and in the placebo group there was a reduction in SBP (0.0118*) of 4 mmHg and of a choline metabolite 3.65 ppm (0.0266*), which does not call into question the validity of these results in the literature. Conclusion The synergism of the functions of these statistically highlighted metabolites contributed to prevention the increase in SBP after fiber intervention in overweight and obese normotensive women.

Sapindales comprise nine families with a mainly tropical distribution and include numerous species of high economic importance. Members of this order are known for the production of chemical constituents with medicinal properties, such as antioxidant, anti-inflammatory, and antimicrobial activity, as well as species with insecticidal properties. Such diversity of chemical compounds is attributed to a variety of secretory structures, which may occur in both vegetative and reproductive organs. During the past decades, tremendous progress has been made in anatomical and analytical chemistry studies, which has led to the next level of knowledge regarding the secretory structures of Sapindales. This comprehensive review embraces the most important data of the secretory structures of Sapindales: ducts, cavities, laticifers, floral and extrafloral nectaries, osmophores, colleters, idioblasts, and trichomes. Our review comprises structural, functional, and evolutionary aspects of these glands, which are fundamental for further studies of the diversification within Sapindales.

Pests and diseases are responsible for most of the losses related to agricultural crops, either in the field or in storage. Moreover, due to indiscriminate use of synthetic pesticides over the years, several issues have come along, such as pest resistance and contamination of important planet sources, such as water, air and soil. Therefore, in order to improve efficiency of crop production and reduce food crisis in a sustainable manner, while preserving consumer’s health, plant-derived pesticides may be a green alternative to synthetic ones. They are cheap, biodegradable, ecofriendly and act by several mechanisms of action in a more specific way, suggesting that they are less of a hazard to humans and the environment. Natural plant products with bioactivity toward insects include several classes of molecules, for example: terpenes, flavonoids, alkaloids, polyphenols, cyanogenic glucosides, quinones, amides, aldehydes, thiophenes, amino acids, saccharides and polyketides (which is not an exhaustive list of insecticidal substances). In general, those compounds have important ecological activities in nature, such as: antifeedant, attractant, nematicide, fungicide, repellent, insecticide, insect growth regulator and allelopathic agents, acting as a promising source for novel pest control agents or biopesticides. However, several factors appear to limit their commercialization. In this critical review, a compilation of plant-derived metabolites, along with their corresponding toxicology and mechanisms of action, will be approached, as well as the different strategies developed in order to meet the required commercial standards through more efficient methods.

Metabolomics has been increasingly used to evaluate metabolic changes associated with morbidities. The objective of this study is to assess the metabolic profile before and after intervention with mixed dietary fiber in overweight and obese hypertensive women. This is an intervention study, and the sample consists of 14 women aged 28 to 58 years. An intervention with 12 g of mixed soluble and insoluble fiber is performed for a period of eight weeks. Serum metabolites are identified using a Bruker 1H NMR spectrometer at 400 MHz. Multivariate data analysis, including principal component analysis (PCA), is used to differentiate the two groups. After supplementation with dietary fiber, there is a significant increase in the peak intensity values of the metabolites HDL-C (0.0010*), choline (0.0012*) and hydroxybutyrate (0.0010*) as well as a decrease in systolic (0.0013*) and diastolic (0.0026*) blood pressure. The analysis of the metabolomic profile allows the identification of metabolites that have been associated in the literature with hypertension and excess weight (choline, hydroxybutyrate and amino acids) and with fiber intake (choline, hydroxybutyrate and amino acids) in addition to an increase in HDL-C. The increase in the detection of the described metabolites possibly occurs due to the presence of pathologies and the use of fiber in the intervention, which also contributes to elevated HDL-c and reduced blood pressure.

Ocotea duckei Vattimo, popularly known as “louro-de-cheiro”, “louro-pimenta”, and “louro-canela” is a member of the Lauraceae family found in the Northeast region of Brazil. It is popularly used to treat neuralgia, dyspepsia, anorexia and pain. This current study aimed to promote the isolation and the identification / determination of new secondary metabolites of the species O. duckei Vattimo. In order to obtain the vegetable drug of O. duckei, its stem barks were harvested and submitted to a drying process followed by pulverization. The Crude Ethanolic Extract (BSE), obtained from the vegetable drug, was then subjected to an alkaloid extraction protocol in order to generate its Total Alkaloid Fraction (TAF). The isolation and identification of chemical compounds were carried out by chromatographic and spectroscopic methods respectively. The chemical investigation of O. duckei resulted in the isolation of three compounds: Ocoteaduccin A (OD-1, 0.020 g), Ocoteaduccin B (OD-2, 0.015 g), and N-methylcoclaurine (OD-3, 0.008 g). O. duckei proved to be a promising species, due to the variety of isolated chemical compounds. Further chemical, pharmacological and toxicological studies must be conducted in order to improve the phytochemical knowledge about this plant.

Monocrotaline (MCT) is a bioactive pyrrolizidine alkaloid (PAs) isolated from Crotalaria retusa seeds. The PAs when taken orally may be toxic to animals and humans. However, studies of pyrrolizidine alkaloids in topic formulations did not show toxic effects, otherwise demonstrated several pharmacological activities. The goal of the present work was to characterize MCT employing thermal analysis (DSC, TG/DTG and DTA) and non-thermal techniques (FTIR and capturing images of the decomposition process). The TG curves presented five mass loss events, at a heating rate of 10 °Cmin−1, being the third event, occurring between 204 °C and 292 °C, the one with the greater decomposition, with a mass loss of 62.2% and with an initial decomposition temperature of about 100 °C. Five events (three endothermic and two exothermic) were observed in the DSC curves at the same heating rate. The first event occurred at temperatures between 133 °C and 149 °C. A sample contraction was observed in the images captured at 150 °C, and it was attributed to a part of the decomposition process. Furthermore, the images of the decomposition process revealed that the sample melts at around 202 °C, which was the temperature of the second event of the DSC curve. The other three events were attributed to the sample decomposition. DTA curves were similar to the DSC curves. Fourier transform infrared spectrometry (FTIR) was employed to compare the spectra of the heated samples at several temperatures (50, 100, 150, 200 and 250 °C), with the spectrum of monocrotaline at room temperature. The spectra were compared by an ad hoc algorithm that performs Pearson correlation analysis. FTIR showed that monocrotaline had a significant change in its structure at 150 °C. The kinetic parameters for degradation process were calculated through the experimental data adjustment in the temperature range of 170–300 °C, using a general kinetic model, which was firstly proposed by Ng and improved by Cai-Liu. The results detected a contribution of kinetic models, mainly geometrical contraction models, with activation energy of 108.39 kJ mol−1 and frequency factor of 4.464 × 1011 min−1. This result corroborates the sample contraction, as seen by the images. With the results of mass loss obtained in the thermogravimetric analysis, the thermal degradation mechanism was proposed in association with the FTIR results.

Introduction: Given the diversity of secondary metabolites produced by species of the genus Erythroxylum, in addition to the many methods that have already been described in the literature, modern screening and identification methodologies, such as dereplication, represent an efficient and quick strategy compared to the classic techniques linked to natural product research. Objective: The objective of the present study was to determine the phenolic profiles obtained from three species of Erythroxylum (Erythroxylum pauferrense Plowman, Erythroxylum pulchrum A.St.-Hil. and Erythroxylum simonis Plowman) by dereplication using liquid chromatography coupled with ESI-MSn and HRESIMS. Material and methods: Ethyl acetate and n-butanolic fractions from crude ethanolic extract of Erythroxylum species were analyzed by HPLC-ESI-MSn and HPLC-HRESIMS, in order to identify its corresponding compounds. Experiments were performed in negative ionization mode, and the metabolites were provisionally identified based on deprotonated molecules, molecular formulas, fragmentation patterns and literature data. The corresponding isolated compounds were characterized by 1 H and 13 C NMR spectroscopy. Results: According to the dereplication method, it was possible to establish and compare the phenolic profile of the corresponding species by the assignment of 55 compounds, most of which were first described in these species and among which some were also new to the Erytroxylum genus. Additionally, nine compounds were isolated, including biphenyl-3,3',4,4'-tetraol, where the mass spectral data were not sufficient for their identification, and reported for the first time in the Erythroxylaceae family. Conclusion: This research contributes to the phytochemical knowledge of the Erythroxylum genus and demonstrates the importance of the dereplication method regarding the investigation of natural products, enabling accurate identification of the metabolites while avoiding the efforts and material expenses involved in the isolation of known compounds.

The chemical investigation of Macroptilium martii (Fabaceae) has provided the identification of twelve compounds obtained by liquid chromatography coupled to mass spectrometry (LC–MS/MS), among which, a new flavonoid: isorhamnetin-3-O-galactose-6′'-O-rhamnose-4′”-O-galactose-2-methylbutyric acid (10) and two other flavonoids already reported. The structural elucidation of the new compound was carried out by HR-ESI-MS spectrometric analysis, ¹H, ¹³C and two-dimensional NMR. Cytotoxic activity of 10 was evaluated towards HCT-116 (colorectal carcinoma), HeLa (cervical carcinoma), SK-MEL-28 (melanoma), PC-3 (prostate cancer) and MDA-MB-231 (breast cancer) cells.

Background: Currently there is a high prevalence of humor disorders such as anxiety and depression throughout the world, especially concerning advanced age patients. Aniba riparia (Nees) Mez. (Lauraceae), popular known as "louro", can be found from the Amazon through Guianas until the Andes. Previous studies have already reported the isolation of alkamide-type alkaloids such as riparin III (O-methyl-N-2,6-dyhydroxy-benzoyl tyramine) which has demonstrated anxiolytic and antidepressant-like effects in high doses by intraperitoneal administration. Methods: Experimental protocol was conducted in order to analyze the anxiolytic-like effect of riparin III at lower doses by intravenous administration to Wistar rats (Rattus norvegicus) (n = 5). The experimental approach was designed to last 15 days, divided in 3 distinct periods of five days: control, anxiogenic and treatment periods. The anxiolytic-like effect was evaluated by experimental behavior tests such as open field and elevated plus-maze test, combined with urine metabolic footprint analysis. The urine was collected daily and analyzed by 1H NMR. Generated data were statistically treated by Principal Component Analysis in order to detect patterns among the distinct periods evaluated as well as biomarkers responsible for its distinction. Results: It was observed on treatment group that cortisol, biomarker related to physiological stress was reduced, indicating anxiolytic-like effect of riparin III, probably through activation of 5-HT2A receptors, which was corroborated by behavioral tests. Conclusion: 1H NMR urine metabolic footprint combined with multivariate data analysis have demonstrated to be an important diagnostic tool to prove the anxiolytic-like effect of riparin III in a more efficient and pragmatic way.