Phytochemical profile and determination of cytotoxicity, acute oral toxicity, genotoxicity, and mutagenicity of aqueous and ethanolic extracts of Pseudobombax marginatum (A. St.-Hil.) A. Robyns.

Pseudobombax marginatum, popularly known as "embiratanha," is widely used by traditional communities as anti-inflammatory and analgesic agent. This study aimed to determine the phytochemical profile as well as cytotoxicity, acute oral toxicity, genotoxicity, and mutagenicity attributed to exposure to aqueous (AqEx) and ethanolic (EtEx) extracts of embiratanha bark. Phytochemical screening was conducted using thin-layer chromatography (TLC). Cell viability was analyzed using MTT assay with human mammary gland adenocarcinoma (MDA-MB-231) and macrophage (J774A.1) cell lines, exposed to concentrations of 12.5, 25, 50, or 100 µg/ml of either extract. For acute oral toxicity, comet assay and micronucleus (MN) tests, a single dose of 2,000 mg/kg of either extract was administered orally to Wistar rats. TLC analysis identified classes of metabolites in the extracts, including cinnamic acid derivatives, flavonoids, hydrolyzable tannins, condensed tannins, coumarins, and terpenes/steroids. In the cytotoxicity assay, the varying concentrations of extracts derived from embiratanha induced no significant alterations in the viability of MDA-MB-231 cells. The lowest concentration of EtEx significantly increased macrophage J774A.1 viability. However, the higher concentrations of AqEx markedly lowered macrophage J774A.1 viability. Animals exhibited no toxicity in the parameters analyzed in acute oral toxicity, comet assay, and MN tests. Further, EtEx promoted a significant reduction in DNA damage index and DNA damage frequency utilizing the comet assay, while the group treated with AqEx exhibited no marked differences. Thus, data demonstrated that AqEx or EtEx of embiratanha may be considered safe at a dose of 2,000 mg/kg orgally under our experimental conditions tested.

Toxicological safety, antioxidant activity and phytochemical characterization of leaf and bark aqueous extracts of Commiphora leptophloeos (Mart.) J.B. Gillett.

This study aimed to characterize the phytochemical profile of bark and leaves aqueous extract Commiphora leptophloeos, and conduct in vivo and in vitro assays to determine the presence of any toxicological consequences due to exposure. The phytochemical analysis was carried out using high-performance liquid chromatography (HPLC). The antioxidant activity was estimated utilizing DPPH free radical scavenging and phosphomolybdenum assays. Cell viability was measured by the MTT method on J774 and human adenocarcinoma cells, which were treated with concentrations of 12,5, 25, 50, 100 or 200 µg/ml of both extracts. Acute oral toxicity, genotoxicity, and mutagenicity assays were determined using a single oral dose of 2000 g/kg in male Swiss albino mice (Mus musculus). Biochemical analysis of the blood and histological analyses of the kidneys, liver, spleen, pylorus, duodenum and jejunum were undertaken. Genotoxicity and mutagenicity were determined utilizing blood samples. Gallic acid, catechin, and epicatechin were identified in the bark and chlorogenic acid in leaves. Data demonstrated a high content of phenolic compounds and flavonoids associated with significant antioxidant potential. No significant signs in damage or symptoms of toxicity were detected. No marked reduction in cell viability was found at lower concentrations tested. On histomorphometry, only the gastrointestinal organs exhibited significant difference. Renal hepatic and blood parameters were within the normal range. No apparent signs of toxicity, genotoxicity, mutagenicity or cytotoxicity were found in vivo and in vitro experiments.

Evaluation of the antioxidant, antibacterial, and antibiofilm activity of the sesquiterpene nerolidol.

The aim of this study was to evaluate the antioxidant, antibacterial, and antibiofilm activities of nerolidol. The antioxidant activity of nerolidol was determined using the total antioxidant activity method. Antibacterial activity was performed using the microdilution method to determine the minimum inhibitory concentration (MIC) against seven standard strains of the ATCC and four bacterial clinical isolates with a resistance profile, following the Clinical and Laboratory Standards Institute (CLSI). The antibiofilm activity of nerolidol was performed using the crystal violet method. The results of the antioxidant test revealed a total antioxidant activity of 93.94%. Nerolidol inhibited the growth of Staphylococcus aureus (MIC = 1 mg/mL), Streptococcus mutans (MIC = 4 mg/mL), Pseudomonas aeruginosa (MIC = 0.5 mg/mL), and Klebsiella pneumoniae (MIC = 0.5 mg/mL). For clinical isolates, nerolidol showed an inhibitory potential against multidrug-resistant P. aeruginosa, K. pneumoniae carbapenemase (MIC = 0.5 mg/mL), methicillin-susceptible S. aureus (MIC = 2 mg/mL), and methicillin-resistant S. aureus (MIC = 2 mg/mL). Nerolidol showed similar antibacterial activity against ATCC strains and hospital clinical isolates with resistance profile, suggesting that even though these strains are resistant to antibiotics, they are still sensitive to nerolidol. Nerolidol exerted a dose-dependent effect on the inhibition of biofilm formation, even at subinhibitory concentrations. Nerolidol inhibited bacterial biofilms of ATCC strains at a rate ranging from 51 to 98%, at concentrations ranging from 0.5 to 4 mg/mL. For clinical bacterial isolates, biofilm inhibition ranged from 6 to 60%. Therefore, the present study showed the antioxidant, antibacterial, and antibiofilm properties of nerolidol.

Effect of acute exposure in swiss mice (Mus musculus) to a fibrinolytic protease produced by Mucor subtilissimus UCP 1262: An histomorphometric, genotoxic and cytological approach.

The fibrinolytic enzyme produced by Mucor subtilissimus UCP 1262 was obtained by solid fermentation and purified by ion exchange chromatography using DEAE-Sephadex A50. The enzyme toxicity was evaluated using mammalian cell lineages: HEK-293, J774.A1, Sarcoma-180 and PBMCs which appeared to be viable at a level of 80%. The biochemical parameters of the mice treated with an acute dose of enzyme (2000 mg/mL) identified alterations of AST and ALT and the histomorphometric analysis of the liver showed a loss of endothelial cells (P < 0.001). However, these changes are considered minimal to affirm that there was a significant degree of hepatotoxicity. The comet assay and the micronucleus test did not identify damage in the DNA of the erythrocytes of the animals treated. The protease did not degrade the Aα and Bß chains of human and bovine fibrinogens, thus indicating that it does not act as anticoagulant, but rather as a fibrinolytic agent. The assay performed to assess blood biocompatibility shows that at dose of 0.3-5 mg/mL the hemolytic grade is considered insignificant. Moreover, the enzyme did not prolong bleeding time in mice when dosed with 1 mg/kg. These results indicate that this enzyme produced is a potential competitor for developing novel antithrombotic drugs.

Assessment of Cytotoxic/Antitumour Potential and in silico Study of Salazinic Acid Isolated from Parmotrema concurrens.

INTRODUCTION: Despite numerous scientific advances, cancer continues to be one of the main causes of death in the world. This situation has driven the search for promising molecules. Lichen substances have been widely described for their pharmacological potential. OBJECTIVE: The present study evaluated the antitumour potential of a depsidone isolated from Parmotrema concurrens- salazinic acid (SAL) - through in vitro, in vivo and in silico studies. METHODS: The molecule was isolated from the acetonic extract of the lichen and recrystallized in acetone. The macrophage J774, sarcoma-180 and MDA-MB-231 cell lines were used for the MTT cytotoxicity assay. The antitumor assay used a murine model (Swiss albino mice) with sarcoma-180. The animals were treated for seven consecutive days with doses of SAL (25 and 50 mg/kg) and 5-fluorouracil (20 mg/kg). RESULTS: Its purity was determined using high-performance liquid chromatography (94%), and its structure was confirmed by H1 and C13 nuclear magnetic resonance. SAL was not considered toxic to cancer cell lines, showing cell viability rates of 79.49 ± 4.15% and 86.88 ± 1.02% for sarcoma-180 and MDA-MB-231, respectively. The tumour inhibition rate was greater than 80% in the animals treated with SAL and 65% for those that received 5-fluorouracil. Simulations of molecular dynamics to estimate the flexibility of the interactions between human thymidylate synthase and derivatives of SAL and 5-fluorouracil revealed that SAL exhibited greater enzymatic interaction capacity, with highly favourable energy, compared to 5-fluorouracil. CONCLUSION: The present results demonstrate the potential of salazinic acid as a tumour inhibition agent.

Biological safety of Syagrus coronata (Mart.) Becc. Fixed oil: Cytotoxicity, acute oral toxicity, and genotoxicity studies.

ETHNOPHARMACOLOGICAL RELEVANCE: Syagrus coronata, popularly known as licuri, is a palm native to caatingas. The fixed oil extract of licuri nuts is used by the population of Northeast Brazil for therapeutic purposes, including as an antifungal, anti-inflammatory, and a cicatrizant agent. However, there is no scientific information on the possible harmful health effects of the oil and hence its medicinal usability is unknown. AIM OF THE STUDY: We aimed to analyze the biological safety and possible antioxidant activity of fixed S. Coronata oil. MATERIALS AND METHODS: Chemical analysis of the oil was performed using gas chromatography with flame ionization detection (CG-FID). The cytotoxicity of varying concentrations of the oil (12.5, 25, 50, 100, and 200 µg/mL) was evaluated using the tetrazolium reduction assay in three cell lines: HEK-293 kidney embryonic cells, J774.A1 macrophages, and the tumor line Sarcoma-180 (S-180). Oral toxicity, genotoxicity, and mutagenicity tests were performed in mice which were administered a single dose of 2000 mg/kg of fixed licuri oil, by gavage. For acute toxicity tests, changes in blood and biochemical parameters, behavior, and weight were analyzed; histomorphometric analyses of the liver, kidney, and spleen were also performed. The comet assay and micronucleus (MN) test were performed to analyze genotoxicity. The antioxidant potential was assessed by the total antioxidant capacity (AAT) and DPPH elimination activity. RESULTS: Licuri oil consists predominantly of saturated fatty acids, and lauric acid is the major compound. The highest concentrations of the oil showed low levels of cytotoxicity; however, LC50 was not reached in any of the tests. The acute toxicity study did not reveal any evidence of adverse effects in animals treated with oil; biochemical investigation of blood showed a decrease in blood concentration of total proteins and uric acid. The kidneys, spleen, and liver showed no morphological changes indicative of a pathological process. Genotoxic or mutagenic activity was not detected through both the comet assay and MN test. In addition, the oil showed low antioxidant activity in both methods. CONCLUSION: Licuri oil from the stem of S. coronata did not present significant toxic effects as well as absence of genetic damage when administered orally. Future studies are needed to investigate its pharmacological potential.

Evaluation of the cytotoxicity, oral toxicity, genotoxicity, and mutagenicity of the latex extracted from Himatanthus drasticus (Mart.) Plumel (Apocynaceae).

ETHNOPHARMACOLOGICAL RELEVANCE: Himatanthus drasticus is a tree popularly known as janaguba. Endemic to Brazil, it is found in the Cerrado and Caatinga biomes, rock fields, and rainforests. Janaguba latex has been used in folk medicine for its antineoplastic, anti-inflammatory, analgesic, and antiallergic activities. However, studies investigating the safety of its use for medicinal purposes are limited. AIM OF THE STUDY: This study aimed to evaluate the toxicity of the latex extracted from H. drasticus. MATERIALS AND METHODS: The latex was extracted from H. drasticus specimens by removing a small area of bark (5 × 30 cm) and then dissolving the exudate in water and lyophilizing it. Phytochemical screening was performed by TLC and GC-MS, protein, and carbohydrate levels. Cell viability was performed by the MTT method. Acute oral toxicity, genotoxicity, and mutagenicity assays were performed in mice. RESULTS: TLC showed the presence of saponins and reducing sugars, as well as steroids and terpenes. The GC-MS analysis of the nonpolar fraction identified lupeol acetate, betulin, and α/ß-amyrin derivatives as the major compounds. The latex was toxic to S-180 cells at 50 and 100 µg/mL. No signals of toxicity or mutagenicity was found in mice treated with 2000 mg/kg of the latex, but genotoxicity was observed in the Comet assay. CONCLUSIONS: H. drasticus latex showed toxicity signals at high doses (2000 mg/kg). Although the latex was not mutagenic to mice, it was genotoxic in the Comet assay in our experimental conditions. Even testing a limit dose of 2000 mg/kg, which is between 10 to 35-fold the amount used in folk medicine, caution must be taken since there is no safe level for genotoxic compounds exposure. Further studies on the toxicological aspects of H. drasticus latex are necessary to elucidate its possible mechanisms of genotoxicity.