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In this work, we investigated in vitro the antioxidant, cytotoxic and anti-leishmanial activities of a lignin extracted from the leaves of Morinda citrifolia. Initially, an analysis of the composition of the sheets was performed, then the lignin was obtained by alkaline delignification and characterized by different techniques: elemental analysis, FT-R, UV–vis, HSQC-NMR, thermal analysis, Py-GC/MS and by GPC. The results showed that the leaves had in their composition cellulose (31.29%), hemicellulose (25.01%), lignin (18.34%), extractives (14.39%) and ash (10.03%). The lignin extraction yield was 89.8%. The lignin obtained is of the GSH type with the following contents 79.39%, 13.58% and 7.03% respectively. Furthermore, it is low molecular weight and thermally stable. It had a phenolic content of 93.3 mg GAE/g and low antioxidant activity. In macrophage cytotoxicity assays, it presented a CC50 of 31.0 μg/mL, showing less toxicity than amphotericin B. In assays against the promastigote forms of Leishmania amazonensis, lignin presented an IC50 of 29.56 μg/mL, a less effective concentration than amphotericin B (IC50 = 0.14 μg/mL). However, it was able to promote inhibition of the parasites, a fact confirmed by structural changes. These findings reinforce that M. citrifolia lignin is a promising macromolecule for use as an antiparasitic and antioxidant agent.

In this article, a series of 20 new thiosemicarbazone derivatives containing indole were synthesized and evaluated for their anti-inflammatory potential. The compounds were obtained through a synthetic route of only two steps, with yields that varied between 33.6 and 90.4%, and characterized by spectroscopic and spectrometric techniques. An initial screening through the lymphoproliferation assay revealed that compounds LT76, LT81, and LT87 were able to inhibit lymphocyte proliferation, with CC50 of 0.56 ± 0.036, 0.9 ± 0.01 and 0.5 ± 0.07 µM, respectively, better results than indomethacin (CC50 > 12 µM). In addition, these compounds were able to suppress the in-vitro production of TNF-α and NO, in addition to stimulating the production of IL-4. Reinforcing in-vitro assays, the compounds were able to inhibit COX-2 similar to Celecoxib showing greater selectivity for this isoform (LT81 SI: 23.06 versus Celecoxib SI: 11.88). Animal studies showed that compounds LT76 (64.8% inhibition after 6 h), LT81 (89% inhibition after 6 h) and LT87 (100% inhibition after 4 h) were able to suppress edema in mice after inoculation carrageenan with greater potency than indomethacin, and immunohistochemistry revealed that the groups treated with LT76, LT81 and LT87 reduced the expression of COX-2, similar or better results when compared to indomethacin. Complementarily, in-silico studies have shown that these compounds have a good pharmacokinetic profile, for respecting the parameters of Lipinski and Veber, showing their good bioavailability. These results demonstrate the potency of thiosemicarbazone derivatives containing indole and confirm their importance as scaffolds of molecules with notorious anti-inflammatory activity.

The leaves of P. edulis were subjected to physicochemical analysis, such as ion content, extractives, and structural molecules. The hexanic, ethanolic and ethyl acetate extracts were submitted to phytochemical analyzes by GC-MS, HPLC-MS, and spectrophotometry. In addition, antioxidant (DPPH, ABTS and TAA methods) potential, antimicrobial (MIC method) action, cytotoxicity and immunostimulant activity (flow cytometry analysis) were performed. The extracts showed a moderate antioxidant capacity and revealed the presence of several metabolites, mainly phenols, such as caffeic acid, p-coumaric acid and luteolin. The ethyl acetate and ethanolic extracts showed antifungal activity. In addition, the extracts did not affect splenocytes viability at 12.5 μg/mL and promoted the production of IL-6, IL-10, IL-17 and TNF-α cytokines. P. edulis extracts showed antifungal and antioxidant activity and were able to induce immunostimulatory action in splenocyte cultures in vitro.

Caesalpinia pulcherrima is a species widely used in folk medicine for various diseases such as fever, infections and mouth ulcers. In addition, scientific studies have reported medicinal properties such as antitumor, antiviral, antibacterial and antifungal. Therefore, the objective of this work was to evaluate if organic extracts obtained from leaves of C. pulcherrima have medicinal properties. Three organic extracts were obtained (hexane, ethyl acetate and ethanol) from the leaves collected from the Soxhlet equipment. The characterization was made by GC-MS and UPLC-MS and biological properties as antioxidant (AAT, DPPH, ABTS and lipid peroxidation radicals), antimicrobial, cytotoxicity and immunostimulant (using splenocytes of mice Balb/c) were investigated. Results showed several classes of secondary metabolites, but the ethyl acetate showed more phenols and flavonoids than the other extracts. Extracts showed good results in antioxidant tests, especially the ethyl acetate, but did not show antibacterial activity. The fungal evaluation showed high antifungal properties, especially the hexanic and the ethyl acetate against Candida tropicalis, Aspergillus terreu, Candida krusei and Cryptococcus neoformans strains. Cytotoxicity evaluation showed that under 25 μg/mL are the safety doses that can be used for in vitro tests, besides that, extracts were able to induce cytokine stimulation. These results show that the ethyl acetate extract was the best formulation found in this study to be used against fungal infections, for antioxidant proposes and for promote immunostimulation.

Effluents from textile processes, when discarded of inappropriately, have been shown to be a major environmental concern. In this way, different methods can be used, among them adsorption is an economical and efficient technique in the removal of dyes. Therefore, we propose to analyze the adsorptive capacity of bacterial cellulose (CB) against effluents containing the dye Remazol Black B (RBB). CB was produced by the bacterium Gluconacetobacter hansenii and characterized by the techniques of FTIR, DRX, TGA / DTG and pH (PCZ). The RBB removal tests were initially performed at different pHs. From the best experimental condition, new tests were performed at temperatures of 30, 40, 60 and 100 ± 2 °C, 150 rpm, pH 3.5, using 0.5 g of adsorbent in the concentrations of dye from 25 to 65 mg·L-1. The kinetic study showed that the system balance was achieved in 80 minutes. The experimental data were better described by the pseudo-second order model. The equilibrium results showed that the experimental data fit the Langmuir model (qmax 17.513 mg·g-1). The thermodynamic parameters of adsorption showed that the process is exothermic, not spontaneous and also presented low system randomness. The activation energy (Ea) was 23.8 kJ·mol-1 characterizing physical adsorption. The residual water was not toxic to animal or microbial cells. Bacterial cellulose proved to be a good low-cost adsorbent, easy to acquire and which can be used in the adsorption process.

Lignins are phenolic macromolecules that have several applications. In this work, we examine some biological activities of a lignin-like macromolecule isolated from the Crataeva tapia leaves, not yet studied to evaluate its potential applications in medicinal and cosmetic formulations. Lignin was obtained by alkaline delignification and its physical-chemical characterization was made by means of FT-IR, UV–Vis, NMR spectroscopy, elementary analysis, molecular mass determination and thermal analysis. Lignin is of the GSH type, with levels of hydrogen (5.10%), oxygen (27.18%), carbon (67.60%), nitrogen (0.12%) and phenolic content of 189.6 ± 9.6 mg GAE/g. In addition, it is a thermally stable macromolecule with low antioxidant activity. Cytotoxicity and cytokine production were assessed by flow cytometry. The photoprotective activity was evaluated by adding different concentrations of lignin to a commercial cream. Lignin was not cytotoxic, it stimulated the production of TNF-α, IL-6 and IL-10 and did not promote a significant change in nitric oxide levels. In addition, this macromolecule was able to promote increased absorption of ultraviolet light from a commercial cream. These results reinforce the ethnopharmacological use of C. tapia leaves and suggest the need for further studies to determine the potential medicinal and cosmetic applications (sunscreen) of lignin from C. tapia leaves.

Caesalpinia pulcherrima is a shrub with worldwide distribution used as an ornamental plant. In this study, we extracted a lignin from the C. pulcherrima leaves and investigated its biological functions. The lignin was characterized by FT-IR, UV–Vis, GPC, TGA and nuclear magnetic resonance (1H and 13C). The antioxidant activity was evaluated using phosphomolybdenum complexation methods (TAA), sequestration of DPPH and ABTS radicals, reducing power, formation of nitrite radical and iron chelating activity (Fe2 +). Antifungal activity was made using Candida spp., Aspergillus spp. and Cryptococcus neoformans strains. Cytotoxicity, oxidative stress, and cytokine production were performed using mouse splenocytes. The lignin showed maximal UV–Vis at ~280 nm, 22.27 L/g·cm of absorptivity and, 2,503 kDa of molecular weight. Phenolic compounds (41.33 ± 0.65 mg GAE/g) and indications of a guaiacyl-syringyl-hydroxyphenyl (GSH)-type composition were found. Antioxidant activities of lignin to TAA (40±1.2%) and to DPPH (16.9±0.2%) was high and showed antifungal potential, especially against Candida spp. (IC50 = 31.3 μg/mL) and C. neoformans (15.6 μg/mL). In mouse splenocytes, the lignin was not cytotoxic and stimulated the cell proliferation and cytokine release. These results indicate that C. pulcherrima lignin has the potential to be used as antifungal and immunostimulant compound.

Pectins are complex heteropolysaccharides made up of a linear main chain of repeated units of galacturonic acid that can promote different biological activities. This work aimed to isolate and elucidate the chemical structure of a polysaccharide similar to pectin, obtained from C. erectus leaves. Furthermore, we evaluate the antioxidant and immunomodulatory potential promoted by this macromolecule. The physical-chemical analyzes showed that the pectin obtained showed low degree of esterification and low molecular weight. In addition, it presented in its structure galacturonic acid, glucose, xylose, rhamnose and arabinose. In antioxidant assays in vitro the pectin expressed high activity for the DPPH and ABTS methods. In addition, the pectin obtained was able to promote the growth of probiotic microorganisms in vitro. Immunological tests have shown that pectin was able to stimulate immune cells through the oxidative stress mechanism, promoting lymphocyte proliferation and activation TCD4+ and inhibit lymphocyte activation TCD8+ and stimulate its effector mechanisms through the production of cytokines and nitric oxide, mainly producing a pro-inflammatory immune response, without causing damage to cells. These results highlight the potential use of pectin extracted from C. erectus leaves as an antioxidant, prebiotic and immunomodulatory agent.

Opuntia ficus-indica and Opuntia cochenillifera are species of Cactaceae, found in the arid regions of the planet. They present water, cellulose, hemicellulose, pectins, extractives, ashes and lignins. Here we aimed to study the immunomodulatory action of lignins from these two species against mice splenocytes, since no study for this purpose has yet been reported. The antioxidant activities of these lignins were evaluated by the DPPH, ABTS, NO assays and total antioxidant activity. Cytotoxicity was evaluated through Annexin V-FITC and propidium iodide-PE probs and cell proliferation was determined by CFSE. Immunomodulation studies with Opuntia lignins obtained were performed through investigation of ROS levels, cytosolic calcium release, changes on mitochondrial membrane potential, cytokine production and NO release. Results showed that Opuntia cochenillifera lignin presented more phenolic amount and antioxidant activities than Opuntia ficius-indica. Both lignins showed high cell viability (>96%) and cell proliferation. Activation signal was observed for both lignins with increase of ROS and cytosolic calcium levels, and changes in mitochondrial membrane potential. In addition, lignins induced high TNF-α, IL-6 and IL-10 production and reduced NO release. Therefore, these lignins present great potential to be used as molecules with a proinflammatory profile, being shown as a promising therapeutic agent.

Objective: To evaluate the structural and chemical composition of plant and the antioxidant and antimicrobial activities promoted by hexanic, ethanolic and ethyl acetate fractions obtained from leaves of Conocarpus erectus. Methods: Organic fractions were characterized through UPLC-MS and GC-MS. Antioxidant potential was performed through DPPH and molybdenum phosphate techniques. Antibacterial and antifungal assays were performed in accordance with Clinical and Laboratory Standards Institute protocols. Results: The obtained biomass of Conocarpus erectus leaves showed the high presence of glucose (0.45 g/L), cellulose (28.69%), Na (55.126 μg/L) and K (31.163 μg/L). We identified seven compounds in the hexanic and ethyl acetate fractions, and eight compounds in ethanolic fraction. Moreover, phenolic compounds are prevalent in all organic fractions with values of (10.04 ± 0.24), (221.26 ± 1.84), (340.53 ± 0.84) mg/g GAE to hexanic, ethyl acetate and ethanolic fraction, respectively. Antioxidant results showed a high potential in ethyl acetate fraction (71.82 ± 6.87)% and (10.89 ± 0.05)% in DPPH and molybdenum phosphate techniques, respectively. The ethanolic fraction showed moderate bacteriostatic and bactericidal activity against Staphylococcus aureus and presented a high fungistatic potential for all Candida species tested. Conclusions: Organic fractions obtained from leaves of Conocarpus erectus present antimicrobial and antioxidant properties, and these findings contribute to scientific information for the effectiveness on use of this plant in the development of a phytotherapic compound.

Objective: To evaluate antimicrobial and antioxidant properties of saline extract from Tithonia diversifolia leaves by phytochemical bioprospecting, and investigate its safety against animal cells. Methods: The saline extract was prepared, with NaCl (0.15 M), by constant stirring of the dried and pulverized leaves, followed by volume reduction by lyophilization. The extract was phytochemical characterized using ultra-performance liquid chromatography, and total phenol and flavonoid analysis also was performed. The antioxidant capacity was determined through DPPH· radical, the antimicrobial property was evaluated against standard bacteria and fungi, and the viability assays were performed against mice splenocytes. Results: Fifteen compounds were identified belonging to two main classes terpenoids and phenolics. The extract showed 22.185 mg GAE/g of total phenolic compounds and 3.220 mg QE/g of flavonoid. Moreover, extract showed higher antioxidant ability similar to butylated hydroxytoluene a standard molecule [(3.042±0.019) mg AAE/g and (4.12±0.10) mg AAE/g to saline extract and butylated hydroxytoluene, respectively]. The antimicrobial assays demonstrated that the extract had a significant antifungal potential against Candida species and could be used with safety against mice splenocytes, in concentrations lower than 50 μg/mL, promoting higher proliferation in these cells. Conclusions: Saline extract from Tithonia diversifolia leaves presents potential antioxidant, antifungal properties and induces immunostimulation in mice splenocytes.