Antituberculosis Activities of Lapachol and ß-Lapachone in Combination with Other Drugs in Acidic pH.

Background: The treatment of multidrug-resistant tuberculosis (MDR-TB) is a challenge to be overcome. The increase of resistant isolates associated with serious side effects during therapy leads to the search for substances that have anti-TB activity, which make treatment less toxic, and also act in the macrophage acidic environment promoted by the infection. Objective: The aim of this study was to investigate lapachol and ß-lapachone activities in combination with other drugs against Mycobacterium tuberculosis at neutral and acidic pH and its cytotoxicity. Design: Inhibitory and bactericidal activities against M. tuberculosis and clinical isolates were determined. Drug combination and cytotoxicity assay were carried out using standard TB drugs and/or N-acetylcysteine (NAC). Results: Both naphthoquinones presented activity against MDR clinical isolates. The combinations with the first-line TB drugs demonstrated an additive effect and ß-lapachone+NAC were synergic against H37Rv. Lapachol activity at acidic pH and its association with NAC improved the selectivity index. Lapachol and ß-lapachone produced cell morphological changes in bacilli at pH 6.0 and 6.8, respectively. Conclusion: Lapachol revealed promising anti-TB activity, especially associated with NAC.

Effect of Lavender (Lavandula angustifolia) Essential Oil on Acute Inflammatory Response.

Lavandula angustifolia is a plant of Lamiaceae family, with many therapeutic properties and biological activities, such as anticonvulsant, anxiolytic, antioxidant, anti-inflammatory, and antimicrobial activities. The aim of this study was to evaluate the effect of Lavandula angustifolia Mill. essential oil (LEO) on acute inflammatory response. LEO was analyzed using gas chromatography-mass spectrometry (GC-MS) and nuclear magnetic resonance spectroscopy (NMR) methods and showed predominance of 1,8-cineole (39.83%), borneol (22.63%), and camphor (22.12%). LEO at concentrations of 0.5, 1, 3, and 10 µg/ml did not present in vitro cytotoxicity. Additionally, LEO did not stimulate the leukocyte chemotaxis in vitro. The LEO topical application at concentrations of 0.25, 0.5, and 1 mg/ear reduced edema formation, myeloperoxidase (MPO) activity, and nitric oxide (NO) production in croton oil-induced ear edema model. In carrageenan-induced paw edema model, LEO treatment at doses of 75, 100, and 250 mg/kg reduced edema formation, MPO activity, and NO production. In dextran-induced paw edema model, LEO at doses of 75 and 100 mg/kg reduced paw edema and MPO activity. In conclusion, LEO presented anti-inflammatory activity, and the mechanism proposed of LEO seems to be, at least in part, involving the participation of prostanoids, NO, proinflammatory cytokines, and histamine.

An optimized protocol for anthraquinones isolation from Rhamnus frangula L.

Different from works described in the literature, which use expansive analytical methods to separation of anthraquinones derivatives (AQs), this communication reported a simple and inexpensive methodology to get them. In this way, the expensive commercial AQs: Chrysophanol, physcione and emodine were extracted from plant material (Rhamnus frangula L.) and isolated by classical column chromatography technique under optimised binary mobile phase gradients (CHCl3 : AcOEt(a), a = 1 to 5%) in excellent yields.

Hepatoprotective Effect of Citral on Acetaminophen-Induced Liver Toxicity in Mice.

High doses of acetaminophen (APAP) lead to acute liver damage. In this study, we evaluated the effects of citral in a murine model of hepatotoxicity induced by APAP. The liver function markers alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), and gamma-glutamyl transferase (γGT) were determined to evaluate the hepatoprotective effects of citral. The livers were used to determine myeloperoxidase (MPO) activity and nitric oxide (NO) production and in histological analysis. The effect of citral on leukocyte migration and antioxidant activity was evaluated in vitro. Citral pretreatment decreased significantly the levels of ALT, AST, ALP, and γGT, MPO activity, and NO production. The histopathological analysis showed an improvement of hepatic lesions in mice after citral pretreatment. Citral inhibited neutrophil migration and exhibited antioxidant activity. Our results suggest that citral protects the liver against liver toxicity induced by APAP.

Protective Effect of Cymbopogon citratus Essential Oil in Experimental Model of Acetaminophen-Induced Liver Injury.

To investigate the hepatoprotective effect of Cymbopogon citratus or lemongrass essential oil (LGO), it was used in an animal model of acute liver injury induced by acetaminophen (APAP). Swiss mice were pretreated with LGO (125, 250 and 500[Formula: see text]mg/kg) and SLM (standard drug, 200[Formula: see text]mg/kg) for a duration of seven days, followed by the induction of hepatotoxicity of APAP (single dose, 250[Formula: see text]mg/kg). The liver function markers alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP) and gamma-glutamyl transferase were determined to evaluate the hepatoprotective effects of the LGO. The livers were used to determine myeloperoxidase (MPO) activity, nitric oxide (NO) production and histological analysis. The effect of LGO on leukocyte migration was evaluated in vitro. Anti-oxidant activity was performed by assessing the free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH) in vitro. LGO pretreatment decreased significantly the levels of ALT, AST and ALP compared with APAP group. MPO activity and NO production were decreased. The histopathological analysis showed an improved of hepatic lesions in mice after LGO pretreatment. LGO inhibited neutrophil migration and exhibited anti-oxidant activity. Our results suggest that LGO has protective activity against liver toxicity induced by paracetamol.

Effect of patchouli (Pogostemon cablin) essential oil on in vitro and in vivo leukocytes behavior in acute inflammatory response.

PURPOSE: The aim of this study was to evaluate the effect of Pogostemon cablin essential oil (PEO) on leukocyte behavior in the inflammatory response. METHODS AND RESULTS: PEO was analyzed using Gas Chromatography/Mass Spectrometry (GC/SM) and Nuclear Magnetic Resonance Spectroscopy (NMR) methods and showed predominance of patchoulol (38.50%), α-bulnesene (20.37%), α-guaiene (12.31%), seychellene (8.33%) and α-patchoulene (4.91%). PEO at concentrations of 1, 3, 10, 30, 60 and 90µg/ml reduced the in vitro neutrophil chemotaxis toward fMLP, and at concentrations of 3 and 10µg/ml, increased the phagocytic activity of neutrophils. Topical application of PEO in high concentrations promoted an increase of ear edema and myeloperoxidase (MPO) activity. However, the oral treatment with 100, 200 and 300mg/kg reduced leukocyte recruitment, nitric oxide (NO) production, and rolling and adherent leukocyte number in the microcirculation. CONCLUSION: PEO affects the leukocyte behavior, and the mechanism proposed of PEO seems to be, at least in part, involving the participation of NO and pro-inflammatory cytokines.

Effect of estragole on leukocyte behavior and phagocytic activity of macrophages.

Estragole, a chemical constituent of the essential oils of many aromatic plants, is used as flavoring in beverage and food industries. In vivo and in vitro experimental assays have shown that EST has sedative, anticonvulsant, antioxidant, antimicrobial, and anesthetic activity. In this work, we evaluate the effect of EST on leukocyte behavior and phagocytic activity of macrophages. In the peritonitis model, EST (500 and 750 mg/kg) decreased the infiltration of peritoneal exudate leukocytes. In vitro chemotaxis assay showed that EST (3, 10, 30, and 60 µg/mL) inhibited neutrophil migration toward fMLP. In the in vivo microcirculation assay, EST at doses of 250, 500, and 750 mg/kg significantly reduced the number of rolling and adherent leukocytes and at doses of 250 and 500 mg/kg decreased number of leukocyte migrated to perivascular tissue. The results showed that EST (3, 10, and 30 µg/mL) was able to stimulate the macrophages phagocytosis but only at concentration of 10 µg/mL promoted an increase in nitric oxide (NO) production. In conclusion, this study showed that EST had potential anti-inflammatory effects, likely by inhibiting leukocyte migration and by stimulating macrophages phagocytosis.

Hepatoprotective Effect of Pretreatment with Thymus vulgaris Essential Oil in Experimental Model of Acetaminophen-Induced Injury.

Acute liver damage caused by acetaminophen overdose is a significant clinical problem and could benefit from new therapeutic strategies. Objective. This study investigated the hepatoprotective effect of Thymus vulgaris essential oil (TEO), which is used popularly for various beneficial effects, such as its antiseptic, carminative, and antimicrobial effects. The hepatoprotective activity of TEO was determined by assessing serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase (ALP) in mice. Their livers were then used to determine myeloperoxidase (MPO) enzyme activity and subjected to histological analysis. In vitro antioxidant activity was evaluated by assessing the free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH•)-scavenging effects of TEO and TEO-induced lipid peroxidation. TEO reduced the levels of the serum marker enzymes AST, ALT, and ALP and MPO activity. The histopathological analysis indicated that TEO prevented acetaminophen-induced necrosis. The essential oil also exhibited antioxidant activity, reflected by its DPPH radical-scavenging effects and in the lipid peroxidation assay. These results suggest that TEO has hepatoprotective effects on acetaminophen-induced hepatic damage in mice.

In vitro genotoxicity of Melaleuca alternifolia essential oil in human lymphocytes.

ETHNOPHARMACOLOGICAL RELEVANCE: The volatile essential oil derived from the plant Melaleuca alternifolia, also called tea tree oil (TTO), is largely employed for its antimicrobial properties against several human pathogens. It is used in many topical formulations to treat cutaneous infections. AIM OF THE STUDY: Since very few studies have been done on the safety and toxicity of the crude Melaleuca alternifolia essential oil, current investigation evaluates the possible genotoxic effects of TTO in human lymphocyte cultures. MATERIAL AND METHODS: The composition of current TTO sample was determined by GC/MS and NMR. The level of cytotoxicity in TTO treated cultures was determined by decrease of mitotic index when compared to that in negative control. The genotoxic potential of TTO was assessed by the in vitro mammalian cell micronucleus and the chromosome aberrations (CA) tests. RESULTS: Twenty-seven compounds were identified, accounting for 98.9% of the constituents. Terpinen-4-ol (42.8%), γ-terpinene (20.4%), p-cymene (9.6%), α-terpinene (7.9%), 1,8-cineole (3%), α-terpineol (2.8%) and α-pinene (2.4%) were the major compounds of the oil sample. None of the tested TTO concentrations (95µg/ml, 182µg/ml and 365µg/ml) caused a significant increase in the observed frequencies of micronuclei when compared to those in the untreated cultures (negative control). Additionally, no significant differences regarding the frequencies of CA were observed among the tested TTO concentrations and the negative control. CONCLUSIONS: Results demonstrate that TTO, in the tested concentrations, is not genotoxic in in vitro mammalian cells.

Anti-inflammatory activity of Ocimum americanum L. essential oil in experimental model of zymosan-induced arthritis.

Essential oils are potential sources of novel components for medicinal use. The present study was performed to investigate the composition and anti-inflammatory activity of Ocimum americanum L. essential oil (OEO) and its components in an experimental model of zymosan-induced arthritis and paw edema. The essential oil was obtained by hydro-distillation and analyzed by gas chromatography-mass spectrometry. Twenty-six components, representing 98.9% of the total oil, were characterized, with linalool (19.63%) and 1,8-cineole (17.27%) as the main components. The OEO and its two constituents inhibited leukocyte influx into the synovial space and reduced paw edema induced by zymosan. The OEO also inhibited interferon-γ levels but did not reduce transforming growth factor-ß levels. Additionally, the OEO protected against leukocyte influx into the synovial membrane and cartilage destruction in knee joints in arthritic mice. These findings indicate that the essential oil of Ocimum americanum L. exerted significant anti-inflammatory effects, likely related to its main compounds.

Effect of Zingiber officinale essential oil on Fusarium verticillioides and fumonisin production.

The antifungal activity of ginger essential oil (GEO; Zingiber officinale Roscoe) was evaluated against Fusarium verticillioides (Saccardo) Nirenberg. The minimum inhibitory concentration (MIC) of GEO was determined by micro-broth dilution. The effects of GEO on fumonisin and ergosterol production were evaluated at concentrations of 500-5000 µg/mL in liquid medium with a 5mm diameter mycelial disc of F. verticillioides. Gas chromatography-mass spectrometry showed that the predominant components of GEO were α-zingiberene (23.9%) and citral (21.7%). GEO exhibited inhibitory activity, with a MIC of 2500 µg/mL, and 4000 and 5000 µg/mL reduced ergosterol biosynthesis by 57% and 100%, respectively. The inhibitory effect on fumonisin B1 (FB1) and fumonisin B2 (FB2) production was significant at GEO concentrations of 4000 and 2000 µg/mL, respectively. Thus, the inhibition of fungal biomass and fumonisin production was dependent on the concentration of GEO. These results suggest that GEO was able to control the growth of F. verticillioides and subsequent fumonisin production.

Evaluation of Anti-Inflammatory Activity of Citrus latifolia Tanaka Essential Oil and Limonene in Experimental Mouse Models.

The genus Citrus (Rutaceae) includes several species of plants that produce some of the most cultivated fruits in the world, providing an appreciable content of essential oil. In folk medicine, they are used as a cholagogue, antipyretic, anti-inflammatory, sedative, and antitoxic effects. Lemon essential oil has been used since ancient times for its antiseptic, carminative, diuretic, and eupeptic effects. In this study, we investigated the anti-inflammatory activity of Citrus latifolia Tanaka essential oil (CLEO) and its main constituent LIM. In the cell viability assay, CLEO and LIM (3, 10, 30, and 90 µ g/mL) had low cytotoxicity. In zymosan-induced peritonitis, LIM (500 mg/kg) decreased the infiltration of peritoneal exudate leukocytes and decreased the number of polymorphonuclear leukocytes. In vitro chemotaxis revealed that CLEO and LIM (1, 3, and 10 µg/mL) promoted a significant reduction of neutrophil migration toward fMLP and LTB4. LIM (500 mg/kg) also reduced TNF- α levels but did not alter IL-10 levels in the peritoneal exudate. In conclusion, this study showed that LIM isolated from CLEO had potential anti-inflammatory effects, likely by inhibiting proinflammatory mediators present in inflammatory exudate and leukocyte chemotaxis.

Inhibitory effect of the essential oil of Curcuma longa L. and curcumin on aflatoxin production by Aspergillus flavus Link.

Aflatoxins are highly toxic, mutagenic, teratogenic and carcinogenic mycotoxins. Consumption of aflatoxin-contaminated food and commodities poses serious hazards to the health of humans and animals. Turmeric, Curcuma longa L., is a native plant of Southeast Asia and has antimicrobial, antioxidant and antifungal properties. This paper reports the antiaflatoxigenic activities of the essential oil of C. longa and curcumin. The medium tests were prepared with the oil of C. longa, and the curcumin standard at concentrations varied from 0.01% to 5.0%. All doses of the essential oil of the plant and the curcumin standard interfered with mycotoxin production. Both the essential oil and curcumin significantly inhibited the production of aflatoxins; the 0.5% level had a greater than 96% inhibitory effect. The levels of aflatoxin B(1) (AFB(1)) production were 1.0 and 42.7 µg/mL, respectively, for the samples treated with the essential oil of C. longa L. and curcumin at a concentration of 0.5%.

Inhibitory effect of anethole in nonimmune acute inflammation.

Anethole [1-methoxy-4-(1-propenyl)benzene] occurs naturally as a major component of the essential oil of star anise (Illicium verum Hook.f., family Illiciaceae), comprising more than 90 % of its volatile components. Studies showed that this substance has antioxidant, antibacterial, antifungal, and anesthetic properties. In this study, the anti-inflammatory properties of anethole in animal models of nonimmune acute inflammation such as croton oil-induced ear edema and carrageenan-induced pleurisy were investigated. The investigated parameters were edema formation, leukocyte migration, and inflammatory mediators involved. Oral administration of anethole at a dose of 250 and 500 mg/kg reduced both the volume of pleural exudates and the number of migrated leukocytes. Levels of nitric oxide (NO) and prostaglandins (PGE2) in the inflammatory exudate were reduced by treatment with anethole, but levels of tumor necrosis factor-α and interleukin-1ß were not significantly altered. In ear edema, the oral treatment with anethole inhibited the formation of exudate and the activity of myeloperoxidase, but not after topical administration. These results suggest that the anethole may be effective in controlling some nonimmune acute inflammation-related disease, probably by an inhibitory action on production and/or release of PGE2 and NO.

Composição química e atividade do óleo essencial de origanum vulgare sobre fungos fitopatogênicos / Chemical composition and activity of origanum vulgare essential oil against phytopathogenic fungi

O orégano (Origanum vulgare) é uma planta aromática amplamente utilizada como condimento na culinária. Das folhas desse condimento obteve-se, a partir de hidrodestilação utilizando um aparelho de Clevenger modificado, um óleo essencial constituído majoritariamente por 4-terpineol (8,3%), acetato de linalila (2,0%), timol (32,0%), carvacrol (50,0%) e espatulenol (4,1%). Testou-se o efeito desse óleo essencial sobre a germinação de esporos e crescimento micelial de alguns fungos causadores de doenças em culturas de importância econômica (Corynespora cassiicola, Fusarium sp., Colletotrichum gloeosporioides e Rhizoctonia solani). Observou-se que todos os fungos testados tiveram inibição completa do crescimento micelial e da germinação de esporos pela ação do óleo essencial de Origanum vulgare para concentrações a partir de 500 ppm. A atividade antifúngica desse óleo essencial deve estar associada à presença dos fenóis monoterpênicos timol e carvacrol, que são reportados na literatura por suas atividades antimicrobianas. Esses resultados sugerem a potencialidade de aplicação do óleo essencial de orégano para o controle alternativo de doenças ocasionadas pelos fungos avaliados nesse trabalho.

Oregano (Origanum vulgare) is an aromatic plant widely used as a culinary condiment. From the leaves of this condiment, it was obtained, through hydrodistillation with a modified Clevenger device, an essential oil comprising 4-terpineol (8.3%), linallyl acetate (2.0%), thymol (32.0%), carvacrol (50.0%) and spathulenol (4.1%). The effect of this essential oil was tested on spore germination and mycelial growth of some fungi (Corynespora cassiicola, Fusarium sp., Colletotrichum gloeosporioides and Rhizoctonia solani), which cause diseases in crops of great economic importance. It was observed that all the tested fungi had complete inhibition of mycelial growth and spore germination, as a result of the action of the Origanum vulgare essential oil in concentrations starting in 500 ppm. The antifungal activity of this essential oil must be associated with the presence of thymol and carvacrol monoterpenic phenols, which are reported in literature for their antimicrobial activity. These results suggest the potential of oregano essential oil application for the alternative control of diseases caused by the fungi evaluated in this work.

Rosmarinus officinalis L. essential oil inhibits in vivo and in vitro leukocyte migration.

Rosmarinus officinalis L. (Lamiaceae), popularly known as rosemary, is used for food flavoring and in folk medicine as an antispasmodic, analgesic, antirheumatic, diuretic, and antiepileptic agent. Few studies have shown the anti-inflammatory effects of rosemary essential oil (REO). This study evaluated the effects of REO on leukocyte migration through in vivo leukocyte migration and in vitro chemotaxis assay. REO was analyzed by using gas chromatography-mass spectometry, and the main components identified were camphor (27.59%), 1,8-cineole (15.74%), α-pinene (16.58%), and ß-myrcene (10.02%). In rats, administration of REO reduced the number of leukocytes that rolled, adhered, and migrated to the scrotal chamber after carrageenan injection. All doses of REO tested significantly inhibited leukocyte chemotaxis induced by casein. The effects of REO on leukocyte migration highlight an important mechanism of the anti-inflammatory action of rosemary.

Inhibitory effects of ginger (Zingiber officinale Roscoe) essential oil on leukocyte migration in vivo and in vitro.

Zingiber officinale Roscoe, popular name ginger, is grown naturally in many parts of the world, including Brazil. Ginger is used in pharmaceutical, cosmetic, and food and beverage industries and the essential oil has been used in folk medicine for manifold conditions including as an analgesic, anti-inflammatory, and antirheumatic. The purpose of this study was to investigate the effects of ginger (Zingiber officinale Roscoe) essential oil (GEO) in an in vitro chemotaxis assay and on leukocyte-endothelial interactions in vivo. GEO was analyzed by GC-MS and the main components identified were ar-curcumene (59%), ß-myrcene (14%), 1,8-cineol (8%), citral (7.5%), and zingiberene (7.5%). Oral administration of GEO (200-500 mg/kg) reduced the rolling and leukocyte adherence after 2 h of carrageenan injection (100 µg) into the scrotal chamber. The number of leukocytes migrated to the perivascular tissue 4 h after the irritant stimulus was also diminished. GEO in all doses tested (10(-4), 10(-3), or 10(-2) µL/mL) caused a significant reduction of leukocyte chemotaxis (35.89 ± 4.33, 30.67 ± 0.70, and 35.85 ± 3.83%, respectively) toward casein stimuli. The data presented showed direct and systemic effects of GEO on leukocyte migration as an important mechanism of the anti-inflammatory action of ginger.