Clécio S. Ramos’s research while affiliated with Federal Rural University of Pernambuco and other places

Here we report the most complete study of a plant used for culinary and medicinal purposes. This study was conducted with Solanum paniculatum L., Solanaceae, mentioned in several ethnobotanical surveys carried out in traditional and urban communities in Brazil. Chromatographic and bromatological analysis were used to determine chemical and nutritional composition; Thermal degradation was determined by TG/DTA and accelerated oxidation test by Rancimat method; anti-inflammatory activity was evaluated by carrageenan-induced mice paw edema model, subcutaneous air pouch model, TNF-α levels and vascular permeability induced by acetic acid; the cytotoxicity was evaluated in human cancer cell lines and in erythrocytes; acute and subchronic toxicity were investigated by administration of the extract concentration by oral route to male and female; the antimicrobial activity was evaluated by disk-diffusion and microdilution methods. The extract showed chlorogenic acid as chemical marker as well as predominance of carbohydrates (47.46 g.100 g− 1) and fibers (37.28 g.100 g− 1). Thermal degradation by TG/DTA was carried out in thirteen steps with endothermic and exothermic events. Roots showed capacity to prolong the stability of soybean oil at 6.55 h when exposed to accelerated thermo-oxidation. Root extract did not cause adverse effects on hematological, biochemical, anatomical or histopathological parameters in an in vivo toxicological evaluation. Extract exhibited anti-inflammatory, cytotoxic and antimicrobial activities. Additionally, a specific HPLC method was developed and validated for the analysis of S. paniculatum root extracts. This study contributes to the safe use and quality control of S. paniculatum roots.

This is the first report of the antimicrobial and antioxidant potential of extract from Piper marginatum roots . The extract showed highest antioxidant activity with an EC 50 of 47.3 ± 0.80 µg/mL and a total phenolic content of 42.7 ± 1.10 mg GAE/g. The extract exhibited strong antimicrobial activity with minimum inhibitory concentrations of 250, 250 and 125 µg/mL for the bacteria Bacillus subtilis , Staphylococcus aureus and fungus Mycobacterium smegmatis. Antimicrobial activity was attributed to ( E,E )- N -Isobutyl -2,4-octadienamide and ( E,E )- N -Isobutyl-2,4-decadienamide amides isolated as major compounds of the roots. Structural elucidation of the two amides was determined based on the interpretation of their IR, UV, MS, ¹ H and ¹³ C NMR spectra. The results contribute significantly to the development of a herbal remedies based on P. marginatum roots.

Solanum paniculatum L., a species endemic to tropical America and used in folk medicine in the treatment of anemia, hepatic and digestive disorders, has been widely studied. However, to date, no previous studies on correlations between the contents of mineral nutrients in plant roots with their contents in soil have been reported. The aim of this study was to determine the main mineral nutrients found in S. paniculatum roots and the soil in their natural habitat. It was observed that S. paniculatum roots grow in soils rich in calcium and had a positive correlation in the concentration of Ca with Fe, Na and K and a negative correlation with Zn and Mg. The results contribute to the knowledge of mineral nutrients in S. paniculatum as well as to its cultivation.

Purpose: To evaluate the effects of rosemary leaf essential oil-based ointments on the healing of rat skin lesions. Methods: Sixty adult male rats, with dorsal excisional skin wounds made surgically under anesthesia, were divided into three groups (n = 20): Sham group (untreated wounds); control group (CG, wounds treated with vehicle); and essential oil (EO) treated group (wounds treated with essential oil-based ointments), administered topically once daily. Skin wounds were evaluated at 4, 7, 14, and 21 days after EO or vehicle treatments. Lesions were analyzed macroscopically for the contraction degree. Formalin-fixed paraffin-embedded sections of skin wounds were used for histopathological evaluation. Results: Macroscopic evaluation showed wounds edges with thin crust without firmness and yellowish color, along with an improvement in wound contraction in EO group when compared to the other groups. A reduced inflammatory reaction, along with newly formed small diameter capillaries and more organized and elongated collagen fibers, were more frequently observed in EO group than in the other groups. Moreover, blood vessel number and collagen fibers density were significantly higher in EO group. Conclusions: Skin lesion treatment with rosemary leaf essential oil-based ointments accelerates the initial stages of healing, reduces inflammation, and increases angiogenesis, collagen fibers density, and wound contraction in rats.

Medicinal plants are used for primary health care in many countries. In Brazil, there are hundreds of street markets selling a wide variety of herbs for medicinal purposes without quality control or scientific evidence; instead, their purported efficacy is based exclusively on empirical ethnobotanical knowledge. The present study evaluated the effectiveness of five medicinal plants widely utilized in Brazil to treat infections, as well as determined their chemical profiles. The results revealed that the five plants investigated (Anacardium occidentale L., Handroanthus impetiginosus Mart., Bumelia sartorum Sw., Zornia brasiliensis Vogel and Cnidosculus urens Pohl) demonstrated moderate to strong antimicrobial activity against most fungi and bacteria tested, principally for infections caused by gram-negative bacteria. The extracts of four plants exhibited MIC of 19.5 µg mL-1 against the bacterium Escherichia coli. The results also confirmed that these five traditional medicinal plants are efficient and inexpensive alternative sources of substances to treat infections. The samples of the commercially marketed plants did not have consistent chemical compositions in at least one type of HPLC, GC/MS, UV or 1H NMR analysis.

This paper proposes the development of a simple experiment with easily accessible and low cost materials, enabling its practice with or without laboratory infrastructure, with feasibility for computational theoretical study. On the other hand, the objective of the work is to develop a chemical experiment that demonstrates that the chromophore curcumin (natural indicator) is responsible for indicating the acidity or basicity of a given solution. The experiment has different applicability, being useful in the approach of different chemical contents, showing potential for multi and interdisciplinary approaches. Subjects such as tautomeric equilibrium, chromophoric compounds, hydrogen potential, UV-Vis electron absorption spectra analysis and molecular modeling are explored.

Amides have been recognized as potent insecticidal natural products but, despite their variety of targets and mechanisms of action, their metabolic fate in insects is virtually unknown. The currently accepted hypothesis is that specialist herbivores are capable of biotransforming xenobiotics rendering them more polar and excretable while generalist insects do not have comparable capacity. The leaves from Piper tuberculatum, rich in insecticide amides, were offered to two insect species found on Piper leaves under natural conditions and also to four generalist grasshoppers in order to compare their capacity of biotransforming xenobiotics. The amides 1-7 were identified in the P. tuberculatum leaves and their corresponding carboxylic acids 8-13 were detected in frass samples of two host insects suggesting that these species promote the amides hydrolysis. The four generalist grasshoppers when offered P. tuberculatum leaves, starved to death after 72 h, indicating a strong antifeedant activity of P. tuberculatum leaves.

The investigation of processes to use oil-rich organic wastes to generate biodiesel is an important research area nowadays. In this respect, quantifying oil/fat and biodiesel with less labor demanding analytical tools such as proton nuclear magnetic resonance (1H NMR) can provide faster and more accurate acquisition of the chemical quality parameters of the organic samples. In the present study, the fat obtained from mango seed kernel (MSK) and its biodiesel were investigated using 1H NMR spectra to identify its physicochemical parameters. The results indicate that MSK fat shows high oxidative stability, and the biodiesel produced from MSK fat was compatible with European (EN 14214) and Brazilian (RANP 07/08) standards. The 1H NMR technique was efficient for providing the chemical parameters of MSK fat and its biodiesel without the need of any pretreatment. In addition, complementary analysis was performed to determine the MSK biodiesel quality.