Polymyxin combined with Ocimum gratissimum essential oil: one alternative strategy for combating polymyxin-resistant Klebsiella pneumoniae.

Introduction. Multidrug-resistant infections present a critical public health due to scarce treatment options and high mortality. Ocimum gratissimum L. essential oil (O.geo) is a natural resource rich in eugenol known for its antimicrobial activity.Hypothesis/Gap Statement. O.geo may exert effective antimicrobial activity against polymyxin-resistant Klebsiella pneumoniae and, when combined with Polymyxin B (PMB), may exhibit a synergistic effect, enhancing treatment efficacy and reducing antimicrobial resistance.Aim. This study aims to investigate the antimicrobial activity of O.geo against polymyxin-resistant K. pneumoniae using in vitro tests and an in vivo Caenorhabditis elegans model.Methodology. The O.geo was obtained by hydrodistillation followed by gas chromatography. The MIC and antibiofilm activity were determined using broth microdilution. Checkerboard and time-kill assays evaluated the combination of O.geo and polymyxin B (PMB), whereas a protein leakage assay verified its action.Results. Eugenol (39.67%) was a major constituent identified. The MIC of the O.geo alone ranged from 128 to 512 µg ml-1. The fractional inhibitory concentration index (0.28) and time-kill assay showed a synergism. In addition, O.geo and PMB inhibited biofilm formation and increased protein leakage in the plasma membrane. The treatment was tested in vivo using a Caenorhabditis elegans model, and significantly increased survival without toxicity was observed.Conclusion. O.geo could be used as a potential therapeutic alternative to combat infections caused by multidrug-resistant bacteria, especially in combination with PMB.

Exploring the antiparasitic and antimicrobial potential of Schinus terebinthifolius Raddi essential oil against fish and shrimp pathogens.

This study aimed to perform in vitro antiparasitic and antimicrobial tests with the essential oil (EO) of Schinus terebinthifolius against of fish and shrimp. The chemical composition of the EO of S. terebinthifolius was determined by gas chromatography. For the antiparasitic test, the protozoan Epistylis sp. obtained from parasitized Oreochromis niloticus was used, and exposed to different concentrations of EO (2%, 1%, 0.5%, 0.25%), and control with 1% grain alcohol. The Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) test with EO of S. terebinthifolius evaluated the antimicrobial potential, with serial dilutions starting at 2% and control with 1% grain alcohol, using the strains of Aeromonas hydrophila (2.2 × 108 CFU mL-1), Edwardsiella tarda, Vibrio parahaemolyticus, V. harveyi, and V. alginolyticus (2.0 × 108 CFU mL-1). Chemical analysis revealed that the major EO compounds of S. terebinthifolius were δ-3-Carene (56.00%) and α-Pinene (16.89%). In the antiparasitic test, the concentration of 2% EO showed 100% efficacy against Epistylis sp. within 5 min. In the antimicrobial tests, the concentration of 2% EO was effective against all bacteria tested. The EO of S. terebinthifolius demonstrated antiparasitic and antimicrobial activity at a concentration of 2%, standing out as an alternative to conventional antibiotics.

Mangaba (hancornia speciosa): exploring potent antifungal and antioxidant properties in lyophilised fruit pulp extract through in vitro analysis.

Mangaba is a fruit native to Brazil, rich in bioactive compounds. To evaluate physicochemical composition, bioactive compounds, antioxidant and antifungal activity of mangaba fruit pulp. Moisture, ash, protein, lipid, energy values and phenolic compounds were determined. Antioxidant activity was determined by capture of 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical. Evaluation of antifungal activity was performed by Minimum Inhibitory Concentration, according to protocols M07-A9 and M27-S3, and minimum fungicidal concentration. Freeze-dried mangaba pulp presented high levels of carbohydrates, low levels of lipids, and high energy density. Phenolic analysis demonstrated that chlorogenic acid was found in the highest concentration, followed by p-coumaric acid and ferulic acid. Mangaba extract showed antioxidant activity like BHT. Mangaba extract inhibited the growth of Candida albicans (ATCC 90028), Cryptococcus gattii (AFLP4), Candida guilliermondii (ATCC 6260) and Candida albicans (MYA 2876). Freeze-dried mangaba inhibited fungal activity associated with antioxidant effect due to presence of phenolic compounds.

An approach to combat multidrug-resistant K. pneumoniae strain using synergistic effects of Ocotea diospyrifolia essential oil in combination with amikacin.

The natural antimicrobial properties of essential oils (EOs) have contributed to the battle against multidrug-resistant microorganisms by providing new ways to develop more effective antibiotic agents. In this study, we investigated the chemical composition of Ocotea diospyrifolia essential oil (OdOE) and its antimicrobial properties combined with amikacin (AMK). Through gas chromatography-mass spectrometry (GCMS) analysis, the primary constituents of OdOE were identified as α-bisabolol (45.8 %), ß-bisabolene (9.4 %), γ-elemene (7.6 %), (Z)- ß-farnesene (5.2 %), spathulenol (3.5 %), (Z)-caryophyllene (3.3 %), and (E)-caryophyllene (3.1 %). In vitro assessments showed that the combined administration of OdOE and AMK exerted a synergistic antibacterial effect on the multidrug-resistant K. pneumoniae strain. This synergistic effect demonstrated bacteriostatic action. OdEO combined with amikacin showed protein extravasation within 2 h of treatment, leading to bacterial death, which was determined by a reduction in viable cell count. The effective concentrations showed hemocompatibility. In vivo assessments using Caenorhabditis elegans as a model showed the survival of 85 % of infected nematodes. Therefore, the combination OdEO combined with amikacin exhibited antimicrobial activity against a multidrug-resistant K. pneumoniae strain. Thus, OdOE is a promising agent that may be considered for development of antimicrobial treatment.

Immunohistochemical Expression Levels of Epidermal Growth Factor Receptor, Cyclooxygenase-2, and Ki-67 in Canine Cutaneous Squamous Cell Carcinomas.

Squamous cell carcinoma (SCC) stands as the second most prevalent skin cancer in dogs, primarily attributed to UV radiation exposure. Affected areas typically include regions with sparse hair and pale or depigmented skin. The significance of spontaneous canine cutaneous SCC as a model for its human counterpart is underscored by its resemblance. This study assesses the expression of key markers-Epidermal Growth Factor Receptor (EGFR), Cyclooxygenase-2 (Cox-2), and Ki-67-in canine cutaneous SCC. Our objective is to investigate the association between their expression levels and classical clinicopathological parameters, unraveling the intricate relationships among these molecular markers. In our retrospective analysis of 37 cases, EGFR overexpression manifested in 43.2% of cases, while Cox-2 exhibited overexpression in 97.3%. The EGFR, Cox-2 overexpression, and Ki-67 proliferation indices, estimated through immunohistochemistry, displayed a significant association with the histological grade, but only EGFR labeling is associated with the presence of lymphovascular emboli. The Ki-67 labeling index expression exhibited an association with EGFR and Cox-2. These findings propose that EGFR, Cox-2, and Ki-67 hold promise as valuable markers in canine SCC. EGFR, Cox-2, and Ki-67 may serve as indicators of disease progression, offering insights into the malignancy of a lesion. The implications extend to the potential therapeutic targeting of EGFR and Cox-2 in managing canine SCC. Further exploration of these insights is warranted due to their translational relevance and the development of targeted interventions in the context of canine SCC.

Casearia sylvestris var. lingua (Càmbess.) Eichler leaves aqueous extract improves colon inflammation through mucogenic, antioxidant and anti-inflammatory actions in TNBS- induced IBD rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Casearia sylvestris var. lingua (Cambess.) Eichler, a member of the Salicaceae family, holds a prominent place in traditional medicine across various cultures due to its versatile therapeutic properties. Historically, indigenous communities have utilized different parts of the plant, including leaves, bark, and roots, to address a wide array of health conditions. Traditional uses of C. sylvestris var. lingua encompasses the treatment of gastrointestinal disorders, respiratory infections, wound healing, inflammation, and stomach ulcers. Pharmacological studies have demonstrated the plant's antimicrobial, anti-inflammatory, antioxidant, analgesic, gastroprotective, and immunomodulatory effects. This signifies the first scientific validation report for C. sylvestris var. lingua regarding its effectiveness against ulcerative colitis. The report aims to affirm the traditional use of this plant through pre-clinical experiments. AIM OF THE RESEARCH: This work uses an aqueous extract from C. sylvestris var. lingua leaves (AECs) to evaluate the acute anti-ulcerative colitis efficacy in rat and HT-29 (human colorectal cancer cell line) models. METHODS: To determine the secondary metabolites of AECs, liquid chromatography with a diode array detector (LC-DAD) study was carried out. 2,4,6-trinitrobenzenesulfonic acid (TNBS, 30 mg/0.25 mL EtOH 30% v/v) was used as an enema to cause acute colitis. Three days were spent giving the C. sylvestris var. lingua extract orally by gavage at dosages of 3, 30, and 300 mg/kg. The same route was used to deliver distilled water to the vehicle and naïve groups. After the animals were sacrificed on the fourth day, intestinal tissues were taken for histological examination and evaluation of biochemical tests such as those measuring superoxide dismutase (SOD), reduced glutathione (GSH), catalase (CAT), malondialdehyde (MDA), nitrite/nitrate, myeloperoxidase (MPO) activity. Additionally, interleukin 1 beta (IL-1ß), tumor necrosis factor alpha (TNF-α), and interleukin 10 (IL-10), were conducted on the intestinal tissues. Additionally, an MTT assay was used to evaluate the effect of AECs on the viability of HT-29 cells. Additionally, a molecular docking study was carried out to compare some potential target proteins with identified chemicals found in AECs. RESULTS: LC-DAD analysis identified five compounds (caffeic acid, ellagic acid, ferulic acid, gallic acid, and quercetin) in AECs. Pre-administration of AECs (3; 30; 300 mg/kg) and mesalazine (500 mg/kg) reduced macroscopic scores (55%, 47%, 45%, and 52%, p < 0.001) and ulcerated areas (70.3%, 70.5%, 57%, and 56%, p < 0.001), respectively. It also increased SOD, GSH, and CAT activities (p < 0.01), while decreasing MDA (p < 0.001), nitrite/nitrate (p < 0.05), and MPO (p < 0.001) activities compared to the colitis group. Concerning inflammatory markers, significant modulations were observed: AECs (3, 30, and 300 mg/kg) lowered levels of IL-1ß and TNF-α (p < 0.001) and increased IL-10 levels (p < 0.001) compared to the colitis groups. The viability of HT-29 cells was suppressed by AECs with an IC50 of 195.90 ± 0.01 µg/mL (48 h). During the molecular docking analysis, quercetin, gallic acid, ferulic acid, caffeic acid, and ellagic acid demonstrated consistent binding affinities, forming stable interactions with the 3w3l (TLR8) and the 3ds6 (MAPK14) complexes. CONCLUSION: These results imply that the intestinal mucogenic, anti-inflammatory, and antioxidant properties of the C. sylvestris var. lingua leaf extract may be involved in its therapeutic actions for ulcerative colitis. The results of the in silico study point to the possibility of quercetin and ellagic acid interacting with P38 and TLR8, respectively, in a beneficial way.

Efficacy of essential oil from ginger (Zingiber officinale) for anesthesia and transport sedation of pacu (Piaractus mesopotamicus).

This study evaluated the anesthetic and sedative effects of the essential oil of Zingiber officinale (EOZO) on juvenile pacu (Piaractus mesopotamicus). Experiment 1 evaluated concentrations of 0, 50, 100, 200 and 400 mg L-1 EOZO for times of induction and recovery from anesthesia. Furthermore, hematological responses and residual components of EOZO in plasma were determined immediately after anesthesia. Experiment 2 evaluated the effect of 0, 10, 20 and 30 mg L-1 EOZO on water quality, blood variables and residual components of EOZO in plasma and tissues (muscle and liver) immediately after 2 h of transport. Survival was 100%. The three main compounds of EOZO [zingiberene (32.27%), ß-sesquiphellandrene (18.42%) and ß-bisabolene (13.93%)] were observed in animal plasma and tissues (muscle and liver) after anesthesia and transport, demonstrating a direct linear effect among the evaluated concentrations. The concentration of 200 mg L-1 EOZO promoted surgical anesthesia of pacu and prevented an increase in monocyte and neutrophil levels, yet did not alter other hematological parameters. The use of 30 mg L-1 EOZO has a sedative effect on juvenile pacu, thereby reducing oxygen consumption during transport. Furthermore, the use of 30 mg L-1 EOZO in transport water prevented an increase in hemoglobin and hematocrit, with minimal influences on other blood variables.

Impact of PNPLA3 and TM6SF2 polymorphisms on the prognosis of patients with MASLD and type 2 diabetes mellitus.

BACKGROUND/AIMS: Longitudinal studies assessing the impact of genetic polymorphisms on outcomes in patients with Type 2 Diabetes Mellitus (T2DM) and Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD) are scarce. This study aimed to evaluate the effect of PNPLA3 and TM6SF2 risk alleles on hepatic and extrahepatic outcomes in T2DM-MASLD individuals. METHODS: Patients' polymorphisms were analysed as follows: PNPLA3 CC, CG and GG; TM6SF2 CC and CT + TT; combined comparing no mutant allele, one allele G or T or ≥2 alleles G or T. Hierarchical models were built to assess associations between polymorphisms and outcomes, independently of confounding factors. Multivariate logistic regression was used for cirrhosis and its complications and extrahepatic cancer, and Cox regression for cardiovascular events (CVEs) and all-cause mortality. RESULTS: In total, 407 T2DM-MASLD patients (62.1 ± 10.5 years, 67.6% women) were followed for 11 (6-13) years. Having at least one G or T allele independently increased the risk of cirrhosis in the separate analysis of PNPLA3 and TM6SF2. Combined polymorphism analysis demonstrated an even higher risk of cirrhosis if two or more risk alleles were present (OR 18.48; 95% CI 6.15-55.58; p < .001). Regarding cirrhosis complications, the risk was higher in PNPLA3 GG and TM6SF2 CT + TT, also with an even higher risk when two or more risk alleles were present in the combined evaluation (OR 27.20; 95% CI 5.26-140.62; p < .001). There were no associations with CVEs or mortality outcomes. CONCLUSION: In T2DM, PNPLA3 and TM6SF2 polymorphisms, individually and additively, impact MASLD severity, with an increased risk of cirrhosis and its complications.

Ocimum basilicum essential oil in pacu Piaractus mesopotamicus: anesthetic efficacy, distribution, and depletion in different tissues.

This study aimed to evaluate the anesthetic activity of Ocimum basilicum essential oil and the distribution and depletion of its major compounds in different tissues of the pacu, Piaractus mesopotamicus. Juveniles (319.08 ± 9.14 g) were individually anesthetized with six concentrations of essential oil from O. basilicum (150, 180, 210, 240, 270, and 300 mg L-1), while in a second experiment, fish (492.39 ± 51.51 g) were subjected to a 10 min immersion bath with essential oil from O. basilicum (300 mg L-1). After anesthetic recovery, blood and tissue samples of the brain, gills, liver, spleen, and white muscle were collected at 0, 0.5, 1.0, 3.0, 6.0, 12.0, and 24 h. A 300 mg L-1 concentration induced anesthesia in the shortest time (193.11 ± 9.31), while at 270 and 300 mg L-1 concentrations, the anesthetic recovery period was the longest (244.33 ± 12.44) Methyl chavicol and linalool were quantified in all tissue samples. The plasma concentrations of methyl chavicol differed (p < 0.05) at all evaluated times. Linalool decreased (p < 0.05) from 0 to 1 h and decreased again only after 12 h. Reduction percentages in 24 h were 92.9% for methyl chavicol, and 97.2% for linalool. Elimination of the compounds methyl chavicol and linalool is slower in the gills, where lower elimination constants (0.03 and 0.15 per h) and longer half-lives (25.84 and 4.53 h), respectively, are noted. In general, essential oil from O. basilicum compounds was readily eliminated, showing promising potential for use as an anesthetic in aquaculture.

Synergy between amikacin and Protium heptaphyllum essential oil against polymyxin resistance Klebsiella pneumoniae.

AIMS: We investigated the chemical composition and the in vitro and in vivo antibacterial effects of Protium heptaphyllum essential oil (PHEO) alone and in combination with antibiotics against polymyxin-resistant Klebsiella pneumoniae isolates. METHODS AND RESULTS: Hydrodistillation was used to obtain PHEO, and gas chromatography coupled with mass spectrometry revealed α-pinene, δ-3-carene, and ß-pinene as major components present in PHEO. Minimum inhibitory concentration was determined using the broth microdilution technique and ranged from 256 to 512 µg ml-1. The checkerboard method showed synergy with the combination of PHEO and amikacin (AMK) against the polymyxin-resistant K. pneumoniae isolates. In 8 of the 10 isolates tested, the fractional inhibitory concentration indexes (FICIs) ranged from 0.06 to 0.5, while in the remaining two isolates, the combination exerted an additive effect (FICI of 0.6 and 1.0), resulting in AMK dose reduce of range 2- to 16-fold, in the presence of PHEO. Analysis using zero interaction potency revealed high synergy score (63.9). In the in vivo assay, the survival of Caenorhabditis elegans was significantly improved in the presence of PHEO (1 µg ml-1) + AMK (µg ml-1) combination as compared to 32 µg ml-1 AMK alone. Furthermore, PHEO concentrations of 256 and 512 µg ml-1 were found to be non-toxic on the experimental model. CONCLUSION: To our knowledge, this is the first report of such type of synergism demonstrating an antimicrobial effect against polymyxin-resistant K. pneumoniae isolates.

Characterization and subchronic oral toxicity of Pentaclethra macroloba (pracaxi) oil in Rattus norvegicus (lin. Wistar).

The trend of replacing antimicrobials as growth promoters in animal nutrition is growing. Functional oils emerge as an alternative because of their richness in bioactive compounds and bioavailability. The present study aims to evaluate the fatty acid profile, antioxidant capacity, composition of phenolic compounds, and toxic capacity in Wistar rats of pracaxi oil (Pentaclethra macroloba). DDPH (2,2-diphenyl-1-picrylhydrazyl), FRAP (Ferric Reducing Antioxidant Power), and ABTS (6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid) were performed to assess antioxidant capacity. The composition of phenolic compounds was determined by specific reagents. For the evaluation of subchronic oral toxicity, 40 Wistar albino rats (20 males and 20 females) were randomized into 10 groups with different levels of pracaxi oil administered orally. The doses administered were 0, 300, 600, 1200 and 2400 mg/kg (Group 1 to 5 females and Group 6 to 10 males). The animals were submitted to evaluations described in the OECD manual (Guide 407). The analytical results showed that pracaxi oil has different fatty acids in its chemical composition: oleic, linoleic, arachidic, and behenic acids, which account for more than 90% of its composition. In a smaller percentage, lauric acid (0.17%), myristic (0.09%), palmitic (1.49%), stearic (3.45%), and linolenic acid (1.39%) were also found. According to the results of the antioxidant tests, pracaxi oil has a high antioxidant capacity and is a product with a high presence of phenolic compounds. Regarding the toxicity assessment, there were no alterations in the clinical signs and weight of organs. However, in histology, there were mild alterations of a possible toxic process with the increase in the oil dose. This research is extremely valuable since pracaxi oil is a product with little information about its potential use in animal nutrition.

Geographical variation in the chemical composition, anti-inflammatory activity of the essential oil, micromorphology and histochemistry of Schinus terebinthifolia Raddi.

ETHNOPHARMACOLOGICAL RELEVANCE: Schinus terebinthifolia Raddi (Anacardiaceae) is rich in essential oil, distinguished by a predominance of monoterpenes and sesquiterpenes, it being widely used in traditional medicine for the treatment of inflammations. AIM OF STUDY: This study's objective was to investigate the chemical composition of the essential oil of S. terebinthifolia (EOST) collected in six states of Brazil, evaluate its anti-inflammatory effects in mice, and analyze the histochemistry and micromorphology of leaves and stems. MATERIALS AND METHODS: Aerial parts of S. terebinthifolia were collected in six states of Brazil, and the essential oil was extracted by hydrodistillation and analyzed by gas chromatography-mass spectrometry (GC-MS). The histochemistry and micromorphology of leaves and stems were performed using standard reagents, light and field emission scanning electron microscopy, beyond energy-dispersive X-ray spectroscopy. The EOST were evaluated for anti-inflammatory activity and hyperalgesia using the carrageenan-induced paw edema methodology. RESULTS: The EOST showed variation across the six states in its yield (0.40%-0.86%) and chemical composition: hydrocarbon monoterpenes (28.76%-47.73%), sesquiterpenes, (31.43%-41.76%), oxygenated monoterpenes (14.31%-19.57%), and oxygenated sesquiterpenes (4.87%-14.38%). Both α-pinene and limonene were predominant constituents of essential in five regions, except for one state where α-phellandrene and limonene were the dominant components. A comprehensive description of the leaf and stem micromorphology and histochemistry was performed. In the in vivo testing, all EOST samples exerted antiedematogenic and anti-hyperalgesic effects, when tested in a carrageenan-induced paw inflammation (mechanical and thermal hyperalgesia) model with oral doses of 30 mg/kg. CONCLUSION: Our results indicate that the EOST samples collected in six Brazilian states differed in their chemical composition but not their anti-inflammatory and antihyperalgesic effects, which was correlated with the synergistic effect of its components, collaborating the etnhopharmacologycal use of this plant due to its an anti-inflammatory effect. Also, micromorphology and histochemistry of leaves and stems presented in this study provide anatomical and microchemical information, which aids species identification.

Green tea beneficial effects involve changes in the profile of immune cells in the adipose tissue of obese mice.

PURPOSE: During obesity, the adipose tissue is usually infiltrated by immune cells which are related to hallmarks of obesity such as systemic inflammation and insulin resistance (IR). Green tea (GT) has been widely studied for its anti-inflammatory actions, including the modulation in the proliferation and activity of immune cells, in addition to preventing cardiovascular and metabolic diseases. METHODS: The aim of the present study was to analyze the population of immune cells present in the subcutaneous and epididymal white adipose tissue (WAT) of mice kept at thermoneutrality (TN) and fed with a high-fat diet (HFD) for 16 weeks, supplemented or not with GT extract (500 mg/kg/12 weeks). RESULTS: The HFD in association with TN has induced chronic inflammation, and IR in parallel with changes in the profile of immune cells in the subcutaneous and epidydimal WAT, increasing pro-inflammatory cytokines release, inflammatory cells infiltration, and fibrotic aspects in WAT. On the other hand, GT prevented body weight gain, in addition to avoiding IR and inflammation, and the consequent tissue fibrosis, maintaining a lower concentration of cytokines and a profile of immune cells similar to the control mice, preventing the harmful modulations induced by both HFD and TN. CONCLUSIONS: GT beneficial effects in WAT abrogated the deleterious effects triggered by HFD and TN, maintaining all immune cells and fibrotic markers at the same level as in lean mice. These results place WAT immune cells population as a potential target of GT action, also highlighting the positive effects of GT in obese mice housed at TN.

Effect of thiamethoxam (organophosphate) on the flies and beetle visitation and cadaveric decomposition process

ABSTRACT Entomofauna associated with decaying cadavers may be useful in criminal investigation, either through the development of immature insects of interest or through entomological succession in corpses. These factors may vary if the insects are exposed to toxic substances that can modify the insect's developmental cycle, as well as its own occurrence, which would imply significant changes in the results of any investigation. However, there are few studies on how contamination by toxic compounds can affect the action of insects on carcasses and their consequence for forensic expertise. Therefore, this study aimed to test the hypothesis that the normal visitation of flies and beetles is altered in insecticide-contaminated carcasses. The experiment was carried out in a sugarcane plantation, using pig carcasses contaminated with insecticide and the same number of carcasses without any type of contamination as a control. In all experiments, the contaminated carcasses reached the final phase of decomposition in a longer time than the uncontaminated carcasses of the control group. A total of 2.767 specimens were collected and identified, 2.103 individuals from the order Diptera and 664 from the order Coleoptera. There was a significant geometric regression adjustment during the decomposition phases only for the control group, different from the contaminated carcasses in which this pattern did not occur. Results show that contamination by insecticide alters decomposition time and phase, altering the action of flies and beetles, affecting the abundance, composition of species as well as their activities, which can alter the data used by experts in criminal experts.

Biological potentialities and chemical composition of Tarenaya aculeata roots and stems

Plant extracts are rich in secondary metabolites responsible for numerous biological activities. This study aimed to evaluate the antioxidant, antibacterial and photoprotective potentials, toxicity and chemical composition of extracts and fractions of stems and roots of Tarenaya aculeata. Phytochemical analyses were performed at qualitative and quantitative levels to evaluate the classes of secondary metabolites. The sun protection factor (SPF) and antioxidant potentials were determined spectrophotometrically, the antibacterial activity was tested against seven bacteria and the toxicity was evaluated using Artemia salina assay. Phytochemical screening revealed the presence of alkaloids, phenolic compounds, flavonoids, glycosides, tannins and saponins. The levels of phenolic compounds, tannins and alkaloids, SPF and antioxidant potentials showed greater results in the stem (SF) and root (RF) fractions in relation to the stem (SE) and root (RE) extracts. All samples exhibited a broad spectrum of antibacterial activity, with MIC values ranging from 31.25 to 250 Hg mL-1. SE, SF and RF caused mortality in A. salina larvae, with LC50 of 347.06, 34.71 and 85.39 ng mL-1, respectively, whereas RE was non-toxic. Thus, T. aculeata is rich in bioactive secondary metabolites, although further studies will be needed to characterize its chemical constituents and investigate their adverse effects.

Los extractos de plantas son ricos en metabolitos secundarios responsables de numerosas actividades biológicas. Este estudio tuvo como objetivo evaluar el potencial antioxidante, antibacteriano y fotoprotector, ademas de la toxicidad y la composición química de extractos y fracciones de tallos y raíces de Tarenaya aculeata. Se realizaron análisis fitoquímicos a nivel cualitativo y cuantitativo para evaluar las clases de metabolitos secundarios. El factor de protección solar (SPF) y los potenciales antioxidantes se determinaron espectrofotométricamente, la actividad antibacteriana se probó contra siete bacterias y la toxicidad se evaluó mediante el ensayo con Artemia salina. El tamizaje fitoquímico reveló la presencia de alcaloides, compuestos fenólicos, flavonoides, glucósidos, taninos y saponinas. Los niveles de compuestos fenólicos, taninos y alcaloides, SPF y potencial antioxidante mostraron mayores resultados en las fracciones de tallo (SF) y raíz (RF) en relación a los extractos de tallo (SE) y raíz (RE). Todas las muestras exhibieron actividad antibacteriana de amplio espectro, con valores de MIC que oscilaron entre 31,25 y 250 Hg mL-1. SE, SF y RF causaron mortalidad en larvas de A. salina, con CL50 de 347,06; 34,71 y 85,39 µg mL-1, respectivamente, mientras que RE no fue tóxico. Por tanto, T. aculeata es rica en metabolitos secundarios bioactivos, aunque se necesitarán más estudios para caracterizar sus componentes químicos e investigar sus efectos adversos.

Extratos vegetais são ricos em metabólitos secundários responsáveis por inúmeras atividades biológicas. Este estudo teve como objetivo avaliar os potenciais antioxidante, antibacteriano e fotoprotetor, toxicidade e composição química de extratos e frações de caules e raízes de Tarenaya aculeata. Análises fitoquímicas foram realizadas em níveis qualitativo e quantitativo para avaliar as classes de metabólitos secundários. Fator de proteção solar (FPS) e potenciais antioxidantes foram determinados espectrofotometricamente, a atividade antibacteriana testada contra sete bactérias e a toxicidade avaliada pelo ensaio com Artemia salina. A triagem fitoquímica revelou a presença de alcaloides, compostos fenólicos, flavonoides, glicosídeos, taninos e saponinas. Os teores de compostos fenólicos, taninos e alcaloides, FPS e potencial antioxidante apresentaram maiores resultados nas frações caule (SF) e raiz (RF) em relação aos extratos de caule (SE) e raiz (RE). Todas as amostras exibiram atividade antibacteriana de amplo espectro, com valores de MIC variando de 31,25 a 250 µg mL-1. SE, SF e RF causaram mortalidade em larvas de A. salina, com LC50 de 347,06, 34,71 e 85,39 Hg mL-1, respectivamente, enquanto RE não foi tóxico. Portanto, T. aculeata é rico em metabólitos secundários bioativos, embora mais estudos sejam necessários para caracterizar seus constituintes químicos e investigar seus efeitos adversos.

Exploration of essential oil from Psychotria poeppigiana as an anti-hyperalgesic and anti-acetylcholinesterase agent: Chemical composition, biological activity and molecular docking.

ETHNOPHARMACOLOGICAL RELEVANCE: Leaves from Psychotria poeppigiana Müll. Arg. (accepted as Palicourea tomentosa (Aubl.) Borhidi), Rubiaceae, has traditionally been used in medicine for treatments of inflammation and pain; Synonymously, Cephaelis elata for the treatment of dementia; However, few scientific studies have been evidence demonstrating this activity. AIM OF THE STUDY: The aim of this study was to investigate the chemical composition of P. poeppigiana essential oil obtained from leaves (EOPP) and its antioxidant, anti-inflammatory and acetylcholinesterase (AChE) activities. Molecular docking simulations were carried out with the main constituents. MATERIALS AND METHODS: EOPP (hydrodistillation) was analysed by gas chromatography-mass spectrometry (GC-MS). The fractionation of EOPP afforded germacrene D and bicyclogermacrene. The antioxidant activity of EOPP was determined by MDA assay. The inflammatory parameters were evaluated using CFA model (with paw edema, mechanical, thermal hyperalgesia, MPO and NAG) in EOPP (30, 100 and 300 mg/kg), germacrene D and bicyclogermacrene (30 mg/kg). The AChE inhibition was evaluated in rat brain structures and molecular docking simulations were carried out using Autodock v.4.3.2. RESULTS: GC-MS analysis identified 19 compounds, and the major compounds were germacrene D (29.38%) and bicyclogermacrene (25.21%). EOPP exhibited high antioxidant capacity (IC50 = 12.78 ± 1.36 µg/mL). All the tested doses of EOPP and both major constituents significantly inhibited cold and mechanical hyperalgesia and significantly blocked the increase in MPO activity 24 h after the CFA injection. There was significant AChE inhibition by EOPP and germacrene D in the cerebral cortex and hippocampus (>50%). Enzyme-ligand molecular modelling showed that the major constituents of EOPP interacted differently with AChE. CONCLUSIONS: The chemical compounds of the essential oil from the leaves of P. poeppigiana is based mainly on terpenes, the sesquiterpenes germacrene D (29.38%) and bicyclogermacrene (25.21%) being the major compounds. EOPP presented antioxidant, anti-inflammatory and anti-acetylcholinesterase (AChE) activities. Besides, enzyme-ligand molecular modelling showed the EOPP may act as an anti-hyperalgesic and AChE inhibitory agent. Taken together, these results might be in accordance with if folk use for pain- and inflammation-related symptoms.

Studies related to the chemical composition, biological activities and toxicity of methanolic extracts of noni (Morinda citrifolia) fruits and leaves.

Morinda citrifolia is a plant that grows in Brazilian northeast and presented a wide range of therapeutic, industrial and technological applications. Based on this, the aim of this work was to study the chemical composition, main biological activities and potential toxicity of its extracts, aiming their industrial application. Important compounds were identified in the methanolic extracts obtained by ultrasonic and Soxhlet extractions from leaves and fruits. GC × GC allowed for the identification of phytosterols, fatty acids and methyl esters, besides others (scopoletin, hydrocarbons, alcohols, terpenes). By HPLC-DAD, compounds like catechin, rutin, quercetin could be also identified and quantified. Their content of polyphenols and flavonoids was considered between the international standards. The extracts showed high antioxidant activities (EC50 ∼ 300 µg mL-1, using DPPH assay) compared with those from the literature. The extracts did not show toxicity or mutagenicity, but presented cytotoxicity, which can indicate their use safely in phytotherapic or nutritional applications.

Determination of preclinical safety of oil obtained from Pachira aquatica Aublet (Malvaceae) seeds: histopathological, biochemical, hematological, and genetic toxicity studies in rats.

Pachira aquatica is a species used for medicinal and food purposes and has numerous phytochemicals that may have systemic toxic effects and damage to genetic material. This study aimed to evaluate acute and short-term oral toxicity, as well as genotoxic and clastogenic effects of oil extracted from P. aquatica (PASO) seeds in rats and Drosophila melanogaster. The results obtained with biochemical and hematological analyses did not show significant changes in any evaluated parameters when compared with reference values for the species used in the study. Data from the histopathological analysis corroborated results found in this study. These findings indicate low acute and short-term toxicity following oral PASO exposure in rats under the experimental conditions tested. Tests performed in rats showed that PASO did not present significant genotoxic or clastogenic effects on the cells analyzed with the three doses tested. Treatment with PASO in the offspring of HB crossing, which showed high cytochrome P450 levels, did not exhibit genotoxic activity, as demonstrated by the SMART test. These results suggest that products from the hepatic oil metabolism did not show genotoxicity under the conditions tested. Together, the results indicate that, under the experimental conditions tested, PASO is safe for repeated intake. As PASO exhibited low potential to cause harmful effects on living organisms, our study encourages further research aimed at assessing its pharmacological activity, since it is a widely consumed plant.

Cytotoxicity, mutagenicity and acute oral toxicity of aqueous Ocotea minarum leaf extracts.

Ocotea minarum (Nees & Mart.) Mez., a native species of Brazil, is used in the treatment of infections and oxidative stress; however, there is no scientific evidence of its toxicological characteristics. We assessed the cytotoxicity, mutagenic activity, and acute oral toxicity of the aqueous extract isolated from O. minarum leaves. The cytotoxicity of this extract was evaluated in tumour and non-tumour cell lines, while the Ames test with a Salmonella Typhimurium was used to determine the mutagenic activity. Wistar rats received a single 2 g/kg dose as part of an LD50 toxicity assessment. Our results showed that the aqueous extract of O. minarum leaves did not present cytotoxic and mutagenic properties and was not toxic, with an LD50 greater than 2 g/kg. Therefore, the O. minarum extracts are pharmacologically safe and can continue to be investigated for the development of new drugs and herbal medicines.