Essential oil of Eugenia stictopetala Mart. ex DC. has antioxidant, antibacterial, and gastrointestinal protective effect

This work aimed to investigate the chemical composition, antioxidant capacity, antibacterial activity, and intestinal and gastric protective effects, in addition to the acute toxicity of the essential oil of E. stictopetala (EOEs). (E)-caryophyllene (18.01%), β-pinene (8.84%), and (E)-nerolidol (8.24%), were the components found in higher content in the essential oil. The EOEs showed antioxidant capacity with IC50 values ranging from 220.28 to 283.67 μg/mL, in addition to presenting antibacterial activity against Escherichia coli, Enterobacter aerogenes, Vibrio cholerae, Salmonella enterica, and Listeria monocytogenes. The essential oil showed a gastroprotective effect, with a reduction in the levels of TNF-α, IL-1β, and IL-6, having multiple pharmacological mechanisms of action. An antidiarrheal effect of EOEs was observed in the castor oil-induced diarrheal model, with reduced intestinal motility. Our findings demonstrate that essential oil can be beneficial in pharmaceutical and therapeutic applications for treating gastrointestinal diseases.

Essential oil from leaves of Croton blanchetianus Baill does not present acute oral toxicity, has antigenotoxic action and reduces neurogenic and inflammatory nociception in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Croton blanchetianus Baill., popularly known as "marmeleiro preto", is an endemic plant from Brazil, being found mainly in the Northeast region. In traditional medicine, the use of medicines based on the leaves of this plant has been reported for the treatment of inflammatory processes, pain, urethral pain, gastrointestinal disorders, rheumatism and headache.

AIM OF THE STUDY

The present work describes the chemical characterization, as well as toxicological evaluation and antinociceptive activity of an essential oil of C. blanchetianus leaves (EOCb).

MATERIALS AND METHODS

The chemical constituents of the oil were identified by gas chromatography coupled to mass spectrometry (GC-MS). In vitro hemolytic activity was tested using mouse blood. Acute toxicity in mice was assessed by the oral or intraperitoneal administration of a single dose of 2000 mg/kg b.w. EOCb (1000 and 2000 mg/kg) was also evaluated for genotoxicity and antigenotoxicity in vivo using the micronucleus test. The antinociceptive activity of EOCb (25, 50 and 100 mg/kg) was evaluated through the abdominal writhing, formalin and tail flick tests.

RESULTS

The chemical characterization indicated as major components α-pinene (21.23%), β-phelandrene (13.92%), terpinolene (13.01%) and germacrene D (10.89%). EOCb did not cause hemolysis and was also neither toxic nor genotoxic, while protected the animals' bone marrow cells from damage caused by cyclophosphamide in oral treatment. However, all animals died after 15 min of intraperitoneal treatment. There was a reduction in the number of abdominal contortions (69.43-89.41%) as well as in licks in the first (38.77-84.47%) and second (59.75-90.74%) phases of the formalin test. In the latter case, the effects were reduced by naloxone and glibenclamide, indicating action via the opioid system and blockage of K+ channels. The latency time in the tail flick test also increased significantly.

CONCLUSION

In conclusion, ingestion of EOCb proved to be safe when administered orally; however, it was lethal intraperitoneally. Additionally, EOCb protected mouse blood cell DNA against the action of cyclophosphamide and showed an antinociceptive effect via the opioid system and dependent on K+ channels.

Antinociceptive and anti-inflammatory activities of essential oil of the leaves of Amburana cearensis (Allemão) A.C. Smith. from the semi-arid region of Northeastern Brazil

ETHNOPHARMACOLOGICAL RELEVANCE

Amburana cearensis (Allemão) A.C. Smith is a medicinal plant with wide distribution in South America, popularly known in Brazil as "cumaru" or "amburana de cheiro". In folk medicine, in the semi-arid region of Northeastern Brazil, infusions, teas and decoctions of leaves of Amburana cearensis have their practical use for treating fever, gastrointestinal disorders, inflammation, and inflammation pain. However, none of the ethnopharmacological properties has been scientifically evaluated using volatile compounds obtained from its leaves (essential oil).

AIM OF THE STUDY

This study investigated the chemical composition, acute oral toxicity, and antinociceptive and anti-inflammatory activities of the essential oil from the leaves of A. cearensis.

MATERIAL AND METHODS

The acute toxicity of the essential oil was investigated in mice. The antinociceptive effect was evaluated using the formalin test and, abdominal writhing induced by acetic acid, being investigated the possible mechanisms of action involved in antinociception. The acute anti-inflammatory effect was investigated through models of carrageenan-induced peritonitis, yeast-induced pyrexia, and carrageenan- and histamine-induced paw inflammation.

RESULTS

No acute toxicity was observed at doses up to 2000 mg/kg; p.o. The antinociceptive effect was statistically equal to morphine. In the formalin assay, the oil showed analgesic activity in the neurogenic and inflammatory phases, having as mechanisms the cholinergic, adenosinergic system, and ATP-sensitive potassium channels (K-ATP). In peritonitis, a reduction in TNF-α and IL-1β levels and leukocyte migration were observed. The antipyretic effect was statistically superior to dipyrone. The reduction in paw edema was statistically superior to the standard in both models.

CONCLUSION

The results obtained not only support the traditional use of the species in inflammatory conditions and pain in folk medicine but also demonstrate that this is a rich source of phytocomponents such as germacrone, which can be used as a natural and sustainable therapeutic agent with industrial applications.

Chemical composition, antinociceptive and anti-inflammatory effects in mice of the essential oil of Psidium cattleyanum Sabine leaves

ETHNOPHARMACOLOGICAL RELEVANCE

One of the native species of the genus most often mentioned by traditional people is Psidium cattleyanum Sabine, which is used mostly to treat disorders of the respiratory, genitourinary, and digestive systems. These symptoms are mainly treated by the decoction of the leaves. Additionally, there are gaps in the in vivo and toxicity investigations of this species.

AIM OF THE STUDY

The aim of this study was evaluate antinociceptive and anti-inflammatory potential of essential oil from P. cattleyanum leaves in vivo.

MATERIALS AND METHODS

Gas chromatography-mass spectrometry (GC/MS) was used to examine the essential oil of P. cattleyanum. The acute toxicity test was then done with a 2000 mg/kg dosage. The oil at 50, 100, and 200 mg/kg orally, as well as the reference medications Morphine 10.0 mg/kg IP and/or Indomethacin 20.0 mg/kg IP, were tested using nociception (abdominal writhing, formalin, and tail immersion) and inflammatory models (paw edema and peritonitis).

RESULTS

The phytochemical assay showed a high concentration of β-caryophyllene (46.68%) and α-caryophyllene (10.81%). In the in vivo assays, P. cattleyanum essential oil proved to be an important antinociceptive agent, reaching 76.96% inhibition of abdominal writhing with acetic acid and 67.12% in the formalin assay. An increase in latency time in the tail test was also reported. In the test with carrageenan, the oil showed significant inhibition compared to the control. A decrease in the migration of leukocytes was also reported in the group treated with P. cattleyanum, reaching 60.49% at the dose of 200 mg/kg.

CONCLUSIONS

The essential oil from the leaves of P. cattleyanum has anti-inflammatory and antinociceptive action and has potential for application in the pharmaceutical and food industry.

Anti-Trichomonas vaginalis activity of essential oils extracted from Caatinga Myrtaceae species and chemical composition of Eugenia pohliana DC

The current trichomoniasis treatment is restrict to 5-nitroimidazole drugs and the emergence of resistant isolates points the need for new therapeutical alternatives. In this study the anti-Trichomonas vaginalis activity of essential oils obtained from Myrtaceae occurring in Caatinga, a plant family with potential antiparasitic activity, was showed. The essential oils varied in their capacity to kill ATCC and fresh clinical T. vaginalis isolates, which was associated with heterogeneity and different patterns of endosymbiosis. Essential oils caused moderate to strong cytotoxicity against mammalian cells, but essential oil of Eugenia pohliana (EOEp) exhibited promising selectivity index towards vaginal epithelial cells. A checkerboard assay revealed a synergistic effect when EOEp and metronidazole were associated, indicating different mechanisms of action. The GC/MS analysis demonstrated the volatile composition of EOEp, with δ-cadinene as majoritary component. This molecule seems to contribute to the trichomonacidal effect and shows potential for the prospection of new antiparasitic compounds.

Eugenia gracillima essential oil has pharmaceutical applications in pain and inflammation without toxic effects in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Eugenia gracillima is widely used by the population in the manufacture of pulps and jellies, with popular reports of its use in the treatment of infections in the urinary system, respiratory and dermatological problems. A previous study reports that EO from E. gracillima leaves proved to be a promising antioxidant agent in combating the promastigote forms of protozoa. Despite this, this species has been little studied due to its pharmacological properties.

STUDY OBJECTIVE

In this study, an essential oil extracted (EO) from Eugenia gracillima leaves was evaluated for its acute toxicity and anti-inflammatory, antinociceptive and behavioral effects in mice.

METHODS

The EO was obtained by hydrodistillation, and the composition analysis was performed by gas chromatography coupled to mass spectrometry. Acute toxicity assessment was performed with observation of hematological parameters and histopathological evaluation, as well as tests to investigate antinociceptive, anti-inflammatory activities and behavioral effects.

RESULTS

Chromatographic analysis showed D-germacrene (16.10%), γ-muurolene-g (15.60%) and bicyclogermacrene (8.53%) as the majority of compounds. In the toxicity evaluation, no death or physiological changes were observed in mice treated with a single oral dose of up to 5000 mg/kg, and it did not lyse erythrocytes in vitro. The hematological parameters evaluated were not changed after treatment; however, 5,000 mg/kg promoted an increase in transaminase levels. In the histopathological evaluation, only the animals that received the dose of 5000 mg/kg showed discrete leukocyte infiltration around the centrilobular vein in the liver. Antinociceptive activity was detected through tests of acetic acid-induced writhing, formalin, and tail flick, promoted in part by the opioid receptor pathway. In the evaluation of anti-inflammatory activity, a reduction in inflammation was observed in the paw edema test and a decrease in the migration of leukocytes and neutrophils in the peritonitis test. The open field and elevated plus maze tests showed that EO did not affect the animals' motor functions or exploratory activity.

CONCLUSION

It was concluded that the essential oil of E. gracillima has potential for the development of pharmaceutical formulations with analgesic and anti-inflammatory actions in non-toxic concentrations.

Influence of seasonal variation on the chemical composition and biological activities of essential oil from Eugenia pohliana DC leaves

The purpose of this study was to analyse the influence of seasonal variation on the chemical composition and antimicrobial, antioxidant and cytotoxicity activities of the essential oil (EO) extracted from the leaves of Eugenia pohliana. Chemical characterisation of the samples- by gas chromatography-mass spectrometry- found 35 and 38 components for summer and winter, respectively, of the EO from E. pohliana leaves, totaling 47 different compounds. Analysis of antioxidant capacity (DPPH, ABTS and TAC) revealed that the summer EO showed greater free radical scavenging capacity than the winter. Similarly, the summer EO exhibited superior antimicrobial potential (MIC=128-512 μg/mL and MMC=128-1024 μg/mL, compared to the winter EO (128-2048 μg/mL and 256-2048 μg/mL, respectively). Results showed that both oils had a low potential to cause haemolysis. This study provides new scientific evidence on the influence of seasonality on the pharmacological properties of E. pohliana leaves and its potential for the development of herbal medicines.

Insecticidal activity of the essential oil of Piper corcovadensis leaves and its major compound (1-butyl-3,4-methylenedioxybenzene) against the maize weevil, Sitophilus zeamais

BACKGROUND

Sitophilus zeamais is one of the most economically impactful pests, attacking various grains and processed foods. Control of this insect has been achieved using synthetic insecticides, exacerbated and careless use of which has led to the development of resistant insect populations, toxicity to non-target organisms and environmental contamination. In this study, Piper corcovadensis leaf essential oil (PcLEO) and its major compound, 1-butyl-3,4-methylenedioxybenzene (BMDB), were investigated as alternative insecticidal agents against S. zeamais.

RESULTS

Characterization of PcLEO showed the presence of 40 compounds. The major components were the phenylpropanoid BMDB (35.77%) and the monoterpenes α-pinene (14.95%) and terpinolene (6.23%). PcLEO and BMDB were toxic by fumigation (half-maximal lethal concentration [LC₅₀ ]: 9.46 and 0.85 μl L^-1 of air, respectively), by contact (half-maximal lethal dose [LD₅₀ ]: 9.38 and 6.16 μg g^-1 of insect, respectively) and ingestion (LC₅₀ : 16.04 and 14.30 mg g^-1 , respectively). In the ingestion test, both PcLEO and BMDB promoted the loss of insect biomass and had a strong deterrent effect. In addition, both were able to inhibit trypsin and α-amylase activities.

CONCLUSION

PcLEO and BMDB exhibited insecticidal activity against S. zeamais, with a toxic effect by fumigation, contact and ingestion, in addition to food deterrence and inhibiting trypsin and α-amylase activities, suggesting their potential for use in the control of this pest.

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.

The essential oil of the leaves of Verbesina macrophylla (Cass.) S.F.Blake has antimicrobial, anti-inflammatory and antipyretic activities and is toxicologically safe

ETHNOPHARMACOLOGICAL RELEVANCE

Verbesina macrophylla (Cass.) S.F.Blake is a medicinal plant from South America, popularly known as "asa de peixe", "asa de peixe branco", "cambará branco" or "cambará guaçu", being used by traditional communities for its healing powers in the form of teas, infusions, liqueurs and extracts, for the treatment of bacterial and fungal infections of the urinary and respiratory tracts, such as kidney problems, bronchitis, inflammation and fever. However, none of the ethnopharmacological properties has been scientifically evaluated.

AIM OF THE STUDY

Based on the ethnopharmacological use of the species, this study investigated the chemical composition, and for the first time acute toxicity, hemolytic, antimicrobial, anti-inflammatory and antipyretic activities of the essential oil from leaves of V. macrophylla.

MATERIAL AND METHODS

The essential oil was obtained from the leaves by hydrodistillation (HD), being characterized by gas chromatography coupled to mass spectrometry (GC-MS) and gas chromatography coupled to flame ionization detection (GC-FID). The antimicrobial activity was evaluated by the broth microdilution technique in bacteria and fungi that cause infections of the respiratory and urinary tract, and toxicological safety regarding hemolytic activity on human red blood cells (hRBCs), and acute toxicity in mice. The anti-inflammatory activity was evaluated by the model carrageenan-induced peritonitis with quantification of the levels of TNF-α and IL-1β in the intraperitoneal fluid, and ear edema induced by croton oil. The antipyretic activity evaluated in mice with pyrexia induced by yeast.

RESULTS

The extraction of essential oil by hydrodistillation (HD) showed a yield of 0.33 ± 0.04%, with its composition constituted mainly by sesquiterpenes of hydrocarbons (94.00%). The essential oil demonstrated antibacterial and antifungal activity, with a low rate of hemolysis in human red blood cells (hRBCs) and no clinical signs of toxicity were observed in animals after acute treatment, which suggested that the LD₅₀ is greater than 5000 mg/kg; p.o. The essential oil demonstrated anti-inflammatory activity reducing levels of pro-inflammatory cytokines TNF-α (38.83%, 72.42% and 73.52%) and IL-1β (37.70%, 75.92% and 87.71%), and ear edema by 49.53%, 85.04% and 94.39% at concentrations of 4, 40 and 400 mg/kg, respectively. The antipyretic activity presented by the essential oil is statistically similar to dipyrone.

CONCLUSION

The set of results obtained, validates the main activities attributed to the traditional use of Verbesina macrophylla (Cass.) S.F.Blake. These data add industrial value to the species, considering that the antimicrobial, anti-inflammatory and antipyretic activities present results similar to the drugs already used also presenting safety. The results suggest that essential oil from V. macrophylla may be used by industry for the development of drugs with natural antimicrobial, anti-inflammatory and antipyretic effect.

First report on the chemical composition of leaf essential oil of Myrciaria pilosa Sobral & Couto and its antimicrobial and antivirulence activities against Staphylococcus aureus

Myrciaria pilosa is a tree species of the Brazilian Caatinga biome. This paper is the first report on the chemical composition and the antimicrobial and antivirulence activities of essential oil extracted from its leaves. The oil was extracted by hydrodistillation. Chemical composition determined by GC-MS and CG-FID revealed 63 compounds; the sesquiterpenes guaiol (13.17%) and (E)-β-caryophyllene (11.26%) dominated. Antimicrobial activity against strains of Staphylococcus aureus was evaluated by the broth microdilution method. It showed minimum inhibitory concentrations (MIC) of 5 μg/mL against evaluated strains and minimum bactericidal concentrations (MBC) ranging from 10 to 20 μg/mL. Evaluation of antivirulence activity showed reductions of 92.0% and 47.2%, respectively, in haemolytic action and production of staphyloxanthin. These findings show that the essential oil of M. pilosa has potential as an antimicrobial drug to control infection by multi-resistant strains of S. aureus.

Chemical composition, antimicrobial activity and synergistic effects with conventional antibiotics under clinical isolates by essential oil of Hymenaea rubriflora Ducke (FABACEAE)

This work aimed to investigate the chemical composition, antimicrobial activity, synergistic effect, and structure changes of the essential oil of Hymenaea rubriflora (EOHr). Forty-five constituents were identified in the essential oil, corresponding to 94.43% of the compounds present, being the main components E-Caryophyllene (36.72 ± 1.05%), Germacrene D (16.13 ± 0.31%), α-Humulene (6.06 ± 0.16%), β-elemene (5.61 ± 0.14%) and δ-Cadinene (3.76 ± 0.07%). Antimicrobial activity was evaluated, presenting antibacterial and antifungal activity with MIC ranging from 0.62 to 40 μL/mL. The essential oil had a synergistic effect when combined with gentamicin and fluconazole. Structural changes were also evaluated and it was possible to observe that EOHr action was related to changes in membrane permeability. The findings obtained here suggest that the use of the essential oil of H. rubriflora in the treatment of infectious diseases presents a potential for the future development of pharmaceutical products.

Chemical composition and evaluation of the antinociceptive, antioxidant and antimicrobial effects of essential oil from Hymenaea cangaceira (Pinto, Mansano & Azevedo) native to Brazil: A natural medicine

ETHNOPHARMACOLOGICAL RELEVANCE

Hymenaea cangaceira Pinto, Mansano & Azevedo (Fabaceae) is a Brazilian medicinal plant widely known as "Jatobá". In folk medicine, it is used to treat infections, respiratory problems, rheumatism, antitumoral, inflammation and pain, however, no activity has been scientifically validated.

AIM OF THE STUDY

This study investigated chemical composition of essential oil from Hymenaea cangaceira (EOHc), antimicrobial, antinociceptive and antioxidant activities besides protection against DNA damage and hemolysis.

MATERIAL AND METHODS

The essential oil was obtained by hydrodistillation, and characterized by GC-MS and GC-FID. The evaluation of antimicrobial activity was performed by microdilution method. The evaluation of the antioxidant activity was performed using the radicals DPPH, ABTS, O₂^- and OH^-, and the protection of DNA damage using plasmid pBR322. Different experimental models were used to evaluate the antinociceptive effect (acetic acid and formalin), and evaluate the mechanisms of action involved with pharmacological antagonists (naloxone, atropine and gibenclamide) in mice. The essential oil was evaluated for hemolysis on human erythrocytes.

RESULTS

The extraction of EOHc showed a yield of 0.18% on a dry basis, presenting high content of hydrocarbon sesquiterpenes (79.04%), high antioxidant activity and protect DNA from damage, besides presenting antifungal and antibacterial activity against Gram-positive and Gram-negative bacteria in vitro. It was found that the essential oil had no acute toxicity in mice up to 5000 mg/kg oral administration (o.a.), in addition to no hemolysis on human erythrocytes. The reduction of antinociceptive activity was 75%, with the opioid system as the mechanism of action.

CONCLUSION

Our results validate the main activities by the traditional use attributed to H. cangaceira for antimicrobial and analgesic activity. In addition, the oil has a potent antioxidant activity, protecting the body against oxidative stress damage, adding new value to an endemic species not known to the industry.

Algrizea Minor Sobral, Faria & Proença (Myrteae, Myrtaceae): chemical composition, antinociceptive, antimicrobial and antioxidant activity of essential oil

This work aimed to investigate the chemical composition, antimicrobial, antinociceptive, acute toxicity and antioxidant activity of the essential oil of Algrizea minor (EOAm). The essential oil presented as the major constituents β-Pinene (56.99%), α-Pinene (16.57%), Germacrene D (4.67%), Bicyclogermacrene (4.66%), (E)-Caryophyllene (3.76%) and Limonene (1.71%). It was verified that the essential oil did not show acute toxicity in the maximum dose of 5,000 mg/kg. In the evaluation of the antinociceptive activity it was verified that the essential oil reduced in 65.84% the number of writhing in the mice, reducing the pain in 59.17%, and the mechanism of action in pain reduction was opioid, similar to morphine. The essential oil also presented significant antimicrobial against Gram positive and Gram-negative bacteria and fungi, and the antioxidant activity was relevant. Therefore, these results demonstrate the great potential for the future development of pharmaceutical products with the essential oil of Algrizea minor (EOAm).