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.

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.

Chemical analysis and antioxidant, anti-inflammatory and toxicological evaluations of the hydromethanolic extract of Psidium guineense Swartz leaves.

ETHNOPHARMACOLOGICAL RELEVANCE: Psidium guineense, popularly known as "araçá-do-campo", is used in popular medicine for the treatment of inflammatory diseases. Our research group studied an essential oil obtained from its leaves and reported anti-inflammatory and analgesic properties. However, to date, the anti-inflammatory actions of the leaf extract have not been evaluated although the traditional folk use of this plant has these indications. AIM OF STUDY: The current study was designed to evaluate the antioxidant and anti-inflammatory effects and toxicity of the hydromethanolic extract of the leaves from P. guineense (HME-PG), as well as to investigate the chemical composition. MATERIALS AND METHODS: HME-PG was chemically investigated by Ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). The antioxidant activity was evaluated with 2, 2-diphenyl-1-picrylhydrazyl (DPPH) and malondialdehyde (MDA). Swiss mice were orally (p.o.) pretreated with HME-PG (30, 100 and 300 mg/kg), and after 1 h received carrageenan via paw injection (edema, cold sensitivity and mechanical hyperalgesia were analyzed) or pleural injection (leukocyte migration was analyzed after 4 h) and for nociception using the formalin model. Acute (14 days) and subacute (28 days) toxicity was assessed with female Wistar rats orally treated with 500 and 2000 mg/kg HME-PG. RESULTS: HME-PG showed high levels of phenolic and flavonoid compounds. Six compounds were identified based on UHPLC-MS/MS analysis, including gallic acid, quercetin, 3'-formyl-2',4',6'-trihydroxy-5'-methyldihydrochalcone, vanillic acid, ursolic acid and corilagin. HME-PG exhibited an IC50 of 48.14 µg/mL in the MDA assay and an IC50 of 45.15 µg/mL in the DPPH test. The treatment with HME-PG (100 and 300 mg/kg) significantly inhibited edema at all time points evaluated, mechanical hyperalgesia after 4 h and the response to cold 3 and 4 h after carrageenan injection and anti-nociceptive effects in both phases of formalin nociception. All oral HME-PG treatments significantly inhibited leukocyte migration and plasma extravasation in the pleurisy model. Toxicity tests did not cause signs of toxicity in the treated animals. CONCLUSIONS: The present study showed that HME-PG has antioxidant and anti-inflammatory properties, and no toxicity was detected after acute or subacute treatment with HME-PG, showing the possibility for the safe traditional use of P. guineense.