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1.
Bol. latinoam. Caribe plantas med. aromát ; 23(3): 382-389, mayo 2024. ilus, tab, graf
Article Dans Anglais | LILACS | ID: biblio-1538151

Résumé

The extraction of geraniol from palmarosa oil using hydrotropic solvents was investigated. Palmarosa oil possesses an appealing rose aroma and properties like anti - inflammatory, antifungal, and antioxidant due to the presence of geraniol. The extraction of geraniol from palmarosa oil by using distillation methods like steam dis tillation and fractional distillation was a laborious process. So hydrotropes were tried for extraction. The geraniol yield and purity depend on parameters like concentration of hydrotrope, solvent volume ratio, and time period. Using the Box Benkhem Desig n (BBD), the extraction process was optimized. One of the major advantages of using hydrotropic solvents is that they were classified as green solvents, and recovery of solvents is also possible. To reduce the extraction time probe sonication is carried ou t. Different hydrotropic solvents with probe sonication are done on palmarosa oil by altering various process parameters to study the separation, yield, and purity.


Se investigó la extracción de geraniol del aceite de palmarosa utilizando solventes hidrotrópicos. El aceite de palmarosa posee un atractivo aroma a rosa y propiedades antiinflamatorias, antifúngicas y antioxidantes debido a la pr esencia de geraniol. La extracción de geraniol del aceite de palmarosa mediante métodos de destilación como la destilación por vapor y la destilación fraccionada ha sido un proceso laborioso. Por lo tanto, se probaron los hidrotropos para la extracción. El rendimiento y la pureza del geraniol dependen de parámetros como la concentración del hidrotropo, la relación de volumen del solvente y el período de tiempo. Se optimizó el proceso de extracción usando el diseño Box Benkhem (BBD). Una de las principales v entajas de usar solventes hidrotrópicos es que se clasifican como solventes verdes y también es posible recuperar los solventes. Para reducir el tiempo de extracción, se lleva a cabo una sonda de ultrasonido. Se realizan diferentes solventes hidrotropos co n sonda de ultrasonido en el aceite de palmarosa alterando varios parámetros del proceso para estudiar la separación, el rendimiento y la pureza.


Sujets)
Huiles végétales/composition chimique , Cymbopogon/composition chimique , Monoterpènes acycliques/composition chimique , Chromatographie en phase gazeuse
2.
Chinese Pharmacological Bulletin ; (12): 431-439, 2024.
Article Dans Chinois | WPRIM | ID: wpr-1013653

Résumé

Aim To investigate the regulatory effect of geraniol on Nrf2/HO-1 signaling pathway after cerebral ischemia-reperfusion(I/R)in rats. Methods In this experiment,all the male SD rats were randomly divided into nine groups receiving the following treatments:sham operation(sham); sham operation+200 mg·kg-1 geraniol; I/R; I/R+50 mg·kg-1 geraniol; I/R+100 mg/kg geraniol; I/R+200 mg·kg-1 geraniol; edaravone; I/R+ brusatol(Nrf2 inhibitor); I/R+200mg·kg-1 geraniol+brusatol. All rats received intraperitoneal injection of geraniol for five consecutive days before MCAO and again after MCAO. During the construction of cerebral I/R injury models,the blood vessels were isolated without any suture in the sham operation and the sham operation +200 mg·kg-1 geraniol groups while the blood vessels with suture in other groups. The damage of neurological function was evaluated by the modified rating scale for neurological function. The TTC,HE and Tunel staining methods were used to determine the cerebral infarction volume,the damage of the ischemic cortex and the apoptosis of cortical cells,respectively. The oxidative stress-related parameters then were measured. The protein expressions of Nrf2 and HO-1 were detected by immunohistochemical staining and the target protein expressions of the injured cortex were detected by Western blot. Results Compared with the model group,it was found that the geraniol treatment significantly repaired neural injury,reduced cerebral infarction volume,cerebral cortex damage and cell apoptosis. Meanwhile,geraniol intervention could significantly increase the expression of Nrf2/HO-1 protein in the right-sided cortex and reduce oxidative stress level. Conclusion Geraniol can attenuate cerebral injury induced by ischemia-reperfusion in rats via activating Nrf2/HO-1 signaling pathway.

3.
Braz. J. Pharm. Sci. (Online) ; 59: e21248, 2023. tab, graf
Article Dans Anglais | LILACS | ID: biblio-1429972

Résumé

Abstract Ischemia/reperfusion (I/R) injury is one of the main causes of acute kidney injury. The pathological mechanisms underlying renal I/R injury are complex and remain uncertain. The protective effects of antioxidant properties of geraniol against renal ischemia reperfusion (I/R) damage were investigated in our study. 28 Wistar albino male rats were randomly selected and 4 groups of n = 7 were created. A right kidney nephrectomy surgery was conducted to all groups under anesthesia. 2 ml SF was given to Groups I and II, 50 mg/kg and 100 mg/ kg geraniol were administered intraperitoneally an hour before ischemia to Groups III and IV, respectively. Except for Group I, 45 minutes of ischemia and 4 hours of reperfusion were applied to the groups. At the end of the experiment, parameters related to oxidative stress and inflammation were determined by comparing kidney function, antioxidant enzyme activities and histological changes. Following comparison of BUN and CRE values with CAT and SOD values in tissue samples of Group I and Group II, an increase in Group II was observed and as a result I/R damage formation occurred. Values of geraniol-treated Group III and Group IV approximated to that of Group I, and that the 50 mg/kg geraniol dose proved more effective than 100 mg/kg geraniol.


Sujets)
Animaux , Mâle , Rats , Lésion d'ischémie-reperfusion/anatomopathologie , Atteinte rénale aigüe/anatomopathologie , Antioxydants/effets indésirables , Radicaux libres , Anesthésie/classification , Rein/malformations
4.
Braz. arch. biol. technol ; 62: e19180438, 2019. tab, graf
Article Dans Anglais | LILACS | ID: biblio-1055415

Résumé

Abstract Possible protective effects of geraniol, known as antioxidant properties, were analyzed biochemically and histologically on experimental long-term renal ischemia/reperfusion I/R injury in rats. This study used 3-4 months old male Wistar albino rats and were divided into 4 groups (n = 7) by random selection: Group I (Sham Group), Group II (I/R+SF), Group III (I/R+50 mg/kg geraniol), and Group IV (I/R+100 mg/kg geraniol). A right nephrectomy was performed in all groups under anesthesia. Groups I and II were inoculated with SF (1 ml/kg) and Groups III and IV were inoculated with 50 mg/kg and 100 mg/kg of geraniol, injected intraperitoneally. For Groups II, III, and IV, I/R durations were determined to be 60 mins ischemia and 24 hours reperfusion. At the end of the experiment, Urea (BUN), Creatinine (CRE) activities in the blood serum and the catalase (CAT), glutathione peroxidase (GPx) and Superoxide dismutases (SOD), enzyme activities in kidney tissue were measured. Histologic sections were examined by light microscopy using Hematoxylin & Eosine. As a result, it was determined that 100 mg / kg geraniol against renal I/R injury shows more antioxidant effect and protection than 50 mg / kg geraniol.


Sujets)
Animaux , Rats , Reperfusion , Ischémie/thérapie , Antioxydants/usage thérapeutique , Rat Wistar , Modèles animaux , Facteurs de protection
5.
Infectio ; 22(1): 9-12, ene.-mar. 2018. tab, graf
Article Dans Anglais | LILACS, COLNAL | ID: biblio-892744

Résumé

Objectives: Candida albicans as important opportunistic dimorphic fungi can cause the life threatening infections in humans. In this study, we evaluated the anticandidal activities of six samples of Pelargonium graveolens essential oils against 31 clinical isolates of C.albicans. Materials and methods: The anti-candidal activity was performed by disc diffusion and micro-broth dilution assays. The chemical compositions of essential oils were analyzed by Gas Chromatography (GC) apparatus. Results: P. graveolens essential oil samples with citronellol (7.7-43.7%) and geraniol (19.3-48.5%) showed the same anti-candidal activity in two different methods. There is no significant difference between the inhibition zone diameters (19.3-24.1 mm), and the MIC and MFC values (1.06-1.48 and 1.5-1.72 µl/ml) of essential oil samples with different percent of citronellol and geraniol. Conclusion: Therefore, P.graveolens essential oils can be used as anti-candidal agent for further studies.


Objetivos: Candida albicans es un importante hongo dimórfico oportunista que puede llegar a amenazar la vida de pacientes con inmunosupresión. En este estudio se evaluaron las actividades anti-Candida de seis muestras de aceites esenciales de Pelargonium graveolens contra 31 aislamientos clínicos de C. albicans. Materiales y métodos: La actividad anti-Candida se realizó por difusión en disco y ensayos de dilución micro-caldo. La composición química de los aceites esenciales se analizó mediante cromatografía de gases. Resultados: Las muestras de aceite esencial de P. graveolens con citronelol (7,7 a 43,7%) y geraniol (19,3 a 48,5%) mostraron la actividad anti-Candida en dos métodos diferentes. No hubo ninguna diferencia significativa entre los diámetros de la zona de inhibición (19,3-24,1 mm), y valores de MFC (1,06 a 1,48 y de 1,5 a 1,72 l / ml) de muestras de aceites esenciales con diferentes porcentajes de citronelol y geraniol. Conclusión: Los aceites esenciales de P.graveolens se pueden utilizar como agentes anti-Candida para estudios adicionales.


Sujets)
Humains , Candida albicans , Huile essentielle , Pelargonium , Isolement du patient , Plantes , Immunosuppression thérapeutique/soins infirmiers , Geranium , Cymbopogon , Champignons
6.
Article Dans Chinois | WPRIM | ID: wpr-851987

Résumé

Iridoids glycosides are a class of compounds which have pharmacological functions of anti-inflammatory, antitumor, hepato-protection, cardio-protection, etc. This review summarizes the biosynthetic pathway, related enzymes (GPPS, GES, G10, G10H, 10-HGO, IS, 7-DLS, 7-DLGT, 7-DLH, LAMT, and SLS) and the application of functional genes in iridoids glycosides, in hopes of regulating the production of metabolites and providing the valuable reference for discovering new drugs.

7.
Article Dans Chinois | WPRIM | ID: wpr-853011

Résumé

Objective: To clone the geraniol-10-hydroxylase (G10H) gene from Gentiana rigescens and analyze the gene expression. Methods: The cDNA sequence of G10H was obtained from G. rigescens using PCR technique. The physical and chemical properties, secondary structure and tertiary structure of G10H protein were forecasted and analyzed using related software. The expression of G10H gene was detected using real-time PCR in roots, stems, and leaves of G. rigescens. Results: The cloned G10H gene was 1 400 bp including 1 248 bp open reading frame and encoding a predicted protein of 415 amino acids. Bioinformatics predicted that the gene encoding protein molecular formula was C2131H3390N586O615S17, the isoelectric point was 7.62, the instability coefficient was 44.20, and the hydrophobic coefficient was -0.245. RT-PCR showed that G10H gene expressed in all organs. And the highest expression level was found in roots, while the lowest in the stems. Conclusion: This G10H gene is cloned from G. rigescens for the first time. The results provide a foundation for exploring the mechanism of gentiopicroside biosynthesis in G. rigescens.

8.
Chinese Pharmacological Bulletin ; (12): 535-541, 2017.
Article Dans Chinois | WPRIM | ID: wpr-511284

Résumé

Aim To study the analgesic effect of geraniol on neuropathic pain and to explore the possible mechanism.Method A neuropathic pain rat model of Spared Nerve Injury(SNI) was established to measure changes in the threshold of paw withdrawal before and after i.p.administration of geraniol.Patch clamp whole-cell recording was performed to measure activity of sodium channels using ipsilateral L3/L4/L5 dorsal root ganglion(DRG) cells isolated from the SNI rats.In addition, HEK 293 cells expressing hNav1.7 and hTRPA1 channels were used for measuring the changes in channel activities with or without geraniol by whole-cell patch clamp.Results Geraniol had a fast analgesic effect on hypersensitivity of mechanical pain in the SNI model.It significantly inhibited sodium channels on DRGs isolated from SNI rats and hNav1.7 but not hTRPA1 channels expressed by HEK293 cells.However, high concentrations of geraniol facilitated the activation of HTRPA1 channel stimulated by AITC.Conclusion Geraniol may abirritate hypersensitivity of mechanical pain in the SNI model by specifically inhibiting Nav1.7 channel activity on the DRG cells.

9.
Tianjin Medical Journal ; (12): 1221-1224, 2016.
Article Dans Chinois | WPRIM | ID: wpr-504038

Résumé

Objective To evaluate the effects of geraniol(GOH) on neointima hyperplasia in rat carotid artery balloon injury model, and explore the potential molecular mechanisms associated with this effect. Methods Totally 20 male Sprague-Dawley (SD) rats were randomly divided into sham operation group (without balloon injury), control group (with balloon injury), low concentration group (with 50 mg/kg GOH intervention after balloon injury) and high concentration group (with 200 mg/kg GOH intervention after balloon injury). The intima to media (I/M) area ratio of neointima was measured by hematoxylin- eosin (HE) staining. The expression of proliferating cell nuclear antigen (PCNA) was measured by immunohistochemical staining at 14th day after operation. As the marker of oxidative stress, the levels of 8-hydroxy-2’-deoxyguanosine (8-OHdG) and malondialdehyde (MDA) were measured by enzyme linked inmmnosorbent assay (ELISA). Results The I/M ratio, IOD, 8-OHdG and MDA values were increased in control group compared with those of sham group. The I/M ratio, IOD and 8-OHdG values were reduced in low concentration group compared with those of control group. But there was no significant difference in MDA level between low concentration group and control group. The I/M ratio, IOD, 8-OHdG and MDA values were significantly reduced in high concentration group compared with those of control group, which showed a more significant inhibitory effect than that of low concentration group (P<0.05). Conclusion GOH could attenuate balloon iniury induced neointima hyperplasia, which might be related to its effect on inhibiting expression of PCNA and decreasing oxidative stress.

11.
Rev. bras. farmacogn ; 24(6): 660-667, Nov-Dec/2014. tab, graf
Article Dans Anglais | LILACS | ID: lil-741833

Résumé

Dermatomycosis causes highly frequent dermal lesions, and volatile oils have been proven to be promising as antifungal agents. The antifungal activity of geraniol, nerol, citral, neral and geranial (monoterpenes), and terbinafine and anidulafungin (control drugs) against seven opportunistic pathogenic yeasts and four dermatophyte species was evaluated by the Clinical and Laboratory Standards Institute microdilution tests. Monoterpenes were more active against dermatophytes than yeasts (geometric mean of minimal inhibitory concentration (GMIC) of 34.5 and 100.4 µg.ml-1, respectively). Trichophyton rubrum was the fungal species most sensitive to monoterpenes (GMIC of 22.9 µg.ml-1). The trans isomers showed higher antifungal activity than the cis. The mechanism of action was investigated evaluating damage in the fungal cell wall (Sorbitol Protection Assay) and in the cell membrane (Ergosterol Affinity Assay). No changes were observed in the MIC of monoterpenes in the sorbitol protection assay.The MIC of citral and geraniol was increased from 32 to 160 µg.ml-1 when the exogenous ergosterol concentrations was zero and 250 µg.ml-1, respectively. The monoterpenes showed an affinity for ergosterol relating their mechanism of action to cell membrane destabilization.

12.
Article Dans Anglais | IMSEAR | ID: sea-151528

Résumé

Mosquitoes are vectors of many diseases like malaria, encephalitis, dengue, filaria, yellow fever etc. and thus possess severe threat to public health. Essential oils of some aromatic plants and many pure terpene compounds have been reported effective against different strains of mosquitoes by many authors. In the present investigation, five reported terpene compounds namely eugenol, geraniol, coumarin, eucalyptol and carvacrol were allowed to dock against octopamine receptor and acetyl cholinesterase protein models of Aedes aegypti and Homo sapiens to evaluate their comparative efficacy in terms of docking performance. All the compounds were found to dock with both the protein models of the two animal systems while some of them were found to better perform against the protein models of A.aegypti than the protein models of H.sapiens which can further be explored in mosquito control programme as a comparatively safe compound(s). The results are discussed on the basis of energy value. 3D structures of proteins were modeled using Modeller9v8. The structures assessment were established using the Procheck, WhatCheck and WhatIF server of Swiss Model Workspace. Ligands were prepared using the Commercial Software Exome HorizonTM.

13.
Indian J Exp Biol ; 2012 Oct; 50(10): 714-717
Article Dans Anglais | IMSEAR | ID: sea-145308

Résumé

Plant oils and oil components were screened in vitro for antibacterial and antifungal activity by disc diffusion method. Minimum Inhibitory Concentrations (MICs) of oils (% v/v) against bacteria and fungi were determined by agar dilution method. Results showed that potential antimicrobial activity was demonstrated by geranium oil, geraniol, and terpineol. These oils and oil components were active against Gram-positive and Gram-negative bacteria pathogens. Antifungal activity was also observed against dermatophytes, yeasts and Aspergillus species. Antimicrobial formulations containing geranium oil, geraniol and terpineol showed strong antibacterial and antifungal activity.

14.
J Environ Biol ; 2012 Mar; 33(2): 255-260
Article Dans Anglais | IMSEAR | ID: sea-146698

Résumé

The present study investigated the chemopreventive potential of geraniol, an acyclic monoterpene alcohol, by monitoring the tumor incidence and analyzing the status of phase II detoxification agents, lipid peroxidation by products and antioxidants in 7,12-dimethylbenz(a)anthracene (DMBA) induced mouse skin carcinogenesis. Skin tumor was developed by painting DMBA (25 μg in 0.1 ml acetone mouse-1) in the shaved back of the mice, twice weekly for 8 weeks. We noticed 100% skin tumor formation in mice treated with DMBA alone. The status of phase II detoxification agents and antioxidants were decreased where as lipid peroxidation by products were increased in tumor bearing mice. Oral administration of geraniol at a dose of 250 mg kg-1 body weight significantly prevented the tumor formation as well as brought back the status of phase II detoxification agents, lipid peroxidation by products and antioxidants to near normal range in DMBA treated mice. Present results suggest that geraniol might have inhibited abnormal cell proliferation occurring in skin carcinogenesis by modulating the activities of phase II detoxification agents and through its free radical scavenging potential.

15.
Article Dans Chinois | WPRIM | ID: wpr-500410

Résumé

Objective: To determine the best time of harvest for Melissa officinalis (M. officinalis) L. to gain highest amounts essential oil.Methods: M. officinalis leaves were harvested in three different stages (before flowering stage, flowering stage and after of flowering stage) and were dried. The essential oils were isolated by hydro- distillation and analyzed by GC/MS.Results: It showed that most essential oils of plants were in before flowering stage. In before flowering stage 37 compounds were identified in leaves oil of M.officinalis. The major components before flowering stage were decadienal (29.38%), geraniol (25.3%), caryophyllene oxide (8.75%), geranyl acetate (5.41%). In the flowering stage 36 compounds were identified as the major components of plant essential oils: decadienal (28.04%), geraniol (24.97%), caryophyllene oxide (7.55%), caryophyllene E (4.65%) and 16 components in the after flowering stage of plant were identified as the major components carvacrol (37.62%), methyl citronellate (32.34%), geranyl acetate (5.82%), caryophyllene (5.50%).Conclusions: The essential oils yields vary considerably from month-to-month and is also influenced by the micro-environment (sun or shade) in which the plant is growing. We found that the essential oil content of M. officinalis L. of leaves is significantly affected by harvesting stages.

16.
Braz. j. med. biol. res ; 44(6): 538-545, June 2011. ilus
Article Dans Anglais | LILACS | ID: lil-589976

Résumé

β-ionone (βI), a cyclic isoprenoid, and geraniol (GO), an acyclic monoterpene, represent a promising class of dietary chemopreventive agents against cancer, whose combination could result in synergistic anticarcinogenic effects. The chemopreventive activities of βI and GO were evaluated individually or in combination during colon carcinogenesis induced by dimethylhydrazine in 48 3-week-old male Wistar rats (12 per group) weighing 40-50 g. Animals were treated for 9 consecutive weeks with βI (16 mg/100 g body weight), GO (25 mg/100 g body weight), βI combined with GO or corn oil (control). Number of total aberrant crypt foci (ACF) and of ACF ≥4 crypts in the distal colon was significantly lower in the GO group (66 ± 13 and 9 ± 2, respectively) compared to control (102 ± 9 and 17 ± 3) and without differences in the βI (91 ± 11 and 14 ± 3) and βI+GO groups (96 ± 5 and 19 ± 2). Apoptosis level, identified by classical apoptosis morphological criteria, in the distal colon was significantly higher in the GO group (1.64 ± 0.06 apoptotic cells/mm²) compared to control (0.91 ± 0.07 apoptotic cells/mm²). The GO group presented a 0.7-fold reduction in Bcl-2 protein expression (Western blot) compared to control. Colonic mucosa concentrations of βI and GO (gas chromatography/mass spectrometry) were higher in the βI and GO groups, respectively, compared to the control and βI+GO groups. Therefore, GO, but not βI, represents a potential chemopreventive agent in colon carcrvpdate=20110329inogenesis. Surprisingly, the combination of isoprenoids does not represent an efficient chemopreventive strategy.


Sujets)
Animaux , Mâle , Rats , Anticarcinogènes/usage thérapeutique , Tumeurs du côlon/prévention et contrôle , Norisoprénoïdes/usage thérapeutique , Terpènes/usage thérapeutique , Anticarcinogènes/pharmacocinétique , Protocoles de polychimiothérapie antinéoplasique/usage thérapeutique , Cancérogènes , Côlon/métabolisme , Tumeurs du côlon/induit chimiquement , Tumeurs du côlon/métabolisme , Diméthylhydrazines , Tests de criblage d'agents antitumoraux/méthodes , Muqueuse intestinale/métabolisme , Norisoprénoïdes/pharmacocinétique , Rat Wistar , Terpènes/pharmacocinétique
17.
São Paulo; s.n; s.n; 2011. 107 p. tab, graf, ilus.
Thèse Dans Portugais | LILACS | ID: biblio-837179

Résumé

O isoprenóide geraniol (GO) apresentou atividade quimiopreventiva quando administrado continuamente durante as fases de iniciação e pós-iniciação em modelo de carcinogênese experimental de cólon por meio da redução do número de focos de criptas aberrantes (FCAs) totais FCAs ≥ 4 criptas e aumento de apoptose no cólon distal. Dessa forma, optou-se por avaliar os eventuais efeitos de três doses de GO (GO1: 25mg/100g de peso corpóreo [p.c.], G02: 50 mg/100g de p.c. e G03: 100 mg/100g de p.c.) em categorias de lesões pré-neoplásicas (LPNs) induzidas por dimetilhidrazina (DMH) durante a fase de pós-iniciação tardia de modelo de carcinogênese experimental de cólon, caracterizada por apresentar lesões mais avançadas e com alto grau de alterações celulares morfológicas, bioquímicas e moleculares denominadas de displasia. Para isso, analisamos diferentes biomarcadores como: FCAs totais e FCAs < ou ≥ 4 criptas em cólons corados com azul de metileno; focos depletados ou positivos de mucina (FPMs ou FDMs) em cólons corados com azul de toluidina; FCAs convencionais ou displásicos por meio de análise histopatológica em cortes corados com hematoxilina e eosina (HE) e focos positivos ou negativos para beta-catenina (FPBCs ou FNBCs) citoplasmática e/ou nuclear por meio de imunoistoquímica. Além disso, células apoptóticas foram identificadas utilizando-se critérios morfológicos clássicos em FCAs ≥ 4 no cólon distaI e a expressão de genes envolvidos na carcinogênese de cólon foi avaliada por meio de RT-PCR: HMGCoA-redutase na mucosa colônica e K-Ras e c-myc em FCAs microdissecados. Em relação ao grupo controle, foi possível observar que o grupo tratado com a maior dose de GO (G03) reduziu a freqüência de FCAs ≥ 4 criptas e FDMs, além de aumentar a apoptose em FCAs ≥ 4 displásicos no cólon distaI (p ≤ 0,05). Já, em relação aos outros biomarcadores e às expressões de HMGCoA-redutase, K-Ras e c-myc não observamos diferenças estatísticas entre os tratamentos (p > 0,05). A partir desses resultados, podemos concluir que a dose de 100 mg/100 g de p.c. de GO mostrou ser mais interessante do ponto de vista quimiopreventivo com efeitos observados principalmente no cólon distaI, onde há maiores relatos de incidência de adenocarcinomas colônicos, tanto em animais quanto em humanos. Assim, a indução da morte celular programada em FCAs ≥ 4 preferencialmente displásicos poderia representar um mecanismo importante de atuação de G03 na redução da freqüência de FCAs ≥ 4 criptas e de FDMs (também utilizado como marcador de displasia) durante a fase de pós-iniciação tardia de modelo de carcinogênese experimental de cólon


The isoprenoid geraniol (GO) showed chemopreventive activity when administered continuously during the initiation and post-initiation phases in an experimental model of colon carcinogenesis by reducing the number of total aberrant crypt foci (ACF) and ACFs ≥ 4 crypts, as well as increasing apoptosis in the distal colon. We therefore chose to evaluate the effects of three different doses of GO (GO1: 25 mg/100 g body weight [b.w.], GO2: 50 mg/100 g b.w. and GO3: 100 mg/100 g of b.w.) on preneoplastic lesions (PNLs) induced by dimethylhydrazine (DMH) during late post-initiation in an experimental model of colon carcinogenesis that is characterized by more advanced lesions and a higher degree of cellular alterations morphological, biochemical and molecular (dysplasia) than previous models. For this study, we analyzed the following biomarkers: total ACFs, ACFs < 4 crypts, and ACFs ≥ 4 erypts in colons stained with methylene blue; mucin-depleted or mucin-positive foci (MDFs or MPFs) in colons stained with toluidine blue; ACFs, through conventional or dysplastie histopathological analysis of sections stained with hematoxylin and eosin (HE); and cytoplasmic vs. nuclear foci reactivity for beta-catenin (foci positive for beta-eatenin (FPBC) or foci negative for beta catenin (FNBC)) using immunohistochemistry. Additionally, apoptotic cells were identified using classical morphologic criteria in ACFs ≥ 4 crypts in the distal colon, and the expression of several genes involved in colon carcinogenesis was assessed by RT-PCR, including HMG-CoA reductase in the colonic mucosa and K-Ras and c-myc in microdissected ACFs. Relative to the control group, we observed that the group receiving the highest dose of GO (GO3 group) had a reduced frequency of both ACFs ≥ 4 crypts and MDFs and that apoptosis increased in dysplastic ACFs ≥ 4 crypts in the distal colon (p < 0, 05). Expression of HMG-CoA reductase, K-Ras and c-myc did not differ between treatments (p > 0, 05). Based on these results, we conclude that the 100 mg/100 g b.w. dose of GO is the most promising, as it shows evidence of chemopreventive effects mainly in the distal colon, which is a region that is reported to have a higher incidence of colonic adenocarcinomas, both in animaIs and in humans. lnduction of programmed cell death by GO3 in ACFs ≥ 4 specifically dysplastic could represent an important mechanism of action in reducing the frequency of both ACFs ≥ 4 crypts and MDFs during late post-initiation in this experimental model of colon carcinogenesis


Sujets)
Animaux , Rats , États précancéreux , Tumeurs du côlon , Carcinogenèse , Dysplasie du col utérin , Chimioprévention
18.
Rev. bras. plantas med ; 13(1): 79-84, 2011. tab
Article Dans Anglais | LILACS | ID: lil-582765

Résumé

A produção de gengibre no Paraná concentra-se no município de Morretes, ocupando uma área de plantio de aproximadamente 300 ha. O objetivo deste trabalho foi avaliar o teor e a composição do óleo essencial de rizomas de gengibre produzidos em Morretes e submetidos a diferentes períodos de secagem em temperatura ambiente. O delineamento experimental foi inteiramente casualizado, em esquema fatorial 5 x 5, com quatro repetições (quatro plantas por repetição), avaliando cinco procedências e cinco períodos de secagem a temperatura ambiente (0, 15, 30, 45 e 60 dias). As extrações de óleo essencial foram realizadas por hidrodestilação em aparelho graduado Clevenger durante três horas e a análise dos constituintes foi realizada por meio de cromatografia em fase gasosa acoplada à espectrometria de massas. A secagem de rizomas de gengibre em temperatura ambiente por até 60 dias resultou na diminuição de teores de óleo essencial na maioria das procedências. Os constituintes geranial e o neral apresentaram maior concentração em todas as procedências e tiveram teores superiores com o aumento nos períodos de secagem. Os teores de geraniol e acetato de geranila foram inferiores após a secagem em todas as procedências, assim como eucaliptol, canfeno, zingibereno e β-bisaboleno na maioria das procedências.


Ginger production in Paraná State, Brazil, has predominated in Morretes Municipality, with around 300 ha cultivated area. The aim of this work was to evaluate the essential oil yield and composition of ginger rhizomes produced in Morretes and subjected to different drying periods at room temperature. Experimental design was completely randomized, in a 5x5 factorial arrangement, with four replicates (four plants each), five origins and five drying periods at room temperature (0, 15, 30, 45 and 60 days). The essential oil was extracted by hydrodistillation in a Clevenger-type device for 3h and the constituents were analyzed by gas chromatography-mass spectrometry (GC/MS). The drying of ginger rhizomes at room temperature for up to 60 days decreased the essential oil yield in most origins. Geranial and neral levels were higher in all origins and as drying periods were longer. Geraniol and geranyl acetate levels decreased after drying in all origins, as well as eucalyptol, camphene, zingiberene and β-bisabolene in most origins.


Sujets)
Conservation aliments/statistiques et données numériques , Zingiber officinale , Huile essentielle/analyse , Rhizome/composition chimique , Analyse de variance , Brésil , Plantes médicinales/enzymologie
19.
Braz. j. med. biol. res ; 42(10): 918-920, Oct. 2009. tab
Article Dans Anglais | LILACS | ID: lil-526191

Résumé

Human infection with fish parasites can result from the ingestion of incompletely cooked or raw fish, giving origin to parasitic diseases such as anisakiasis, caused by parasites of the Anisakidae family. The present study assessed the in vitro larvicidal effect of two monoterpene compounds, geraniol and citronellal, against Contracaecum sp (Nematoda: Anisakidae). Four hundred live larvae of Contracaecum sp obtained from "traíra" fish (Hoplias malabaricus, Bloch, 1974) were analyzed on 40 Petri dishes (10 larvae each) with the compounds to be tested. The final concentrations tested for each compound were 250, 125, 62.5, and 31.2 µg/mL and the evaluation was carried out at five different times (2, 4, 8, 24, and 48 h). The larvicidal action of geraniol and citronellal was statistically superior (P < 0.005) to the control (1 percent ethanol) at concentrations of 250 and 31.2 µg/mL (geraniol) and 250, 125, and 62.5 μg/mL (citronellal). However, no larvicidal activity was observed at concentrations of 125 and 62.5 µg/mL for geraniol and 31.2 µg/mL for citronellal. When the larvicidal action of geraniol was compared to that of citronellal, the former was found to be statistically superior (P < 0.05) to the latter at concentrations of 250 and 31.2 μg/mL. On the other hand, citronellal was statistically superior (P < 0.005) to geraniol at concentrations of 125 and 62.5 μg/mL. The larval mortality rate in terms of time (hours) was higher for geraniol with the passing of time at the 250 μg/mL concentration. At this concentration (in 48 h) the best larvicidal effect was observed with 90 percent lethality. The larvae were considered to be dead using no motility and loss of structural integrity as parameters. The data indicate that natural terpene compounds should be more explored for antihelminthic activity and can be useful for other studies about anisakiasis treatment.


Sujets)
Animaux , Aldéhydes/pharmacologie , Antihelminthiques antinématodes/pharmacologie , Monoterpènes/pharmacologie , Nematoda/effets des médicaments et des substances chimiques , Terpènes/pharmacologie , Évaluation préclinique de médicament , Larve/effets des médicaments et des substances chimiques , Nematoda/croissance et développement , Tests de sensibilité parasitaire
20.
Rev. bras. farmacogn ; 17(4): 557-564, out.-dez. 2007. graf, tab
Article Dans Anglais | LILACS | ID: lil-476205

Résumé

Java citronella (Cymbopogon winterianus Jowitt) is member of the Poaceae family. Java citronella volatile oil has been reported to be among the volatile oils, showing repellent, antimycotic, and acaricide activities. It has been known that agronomical factors have a great effect on both the quality and quantity of essential metabolites. For this reason, it is necessary to determine optimum levels of agronomical factors affecting plant growth and production. Harvest time and drying are very important agronomical factors. This study has been conducted in the Research farm of the " Universidade Federal de Sergipe" , Agronomical Engineering Department along 2002-2003 on the base of factorial experiment in randomized complete block design with three replications. Java citronella was cultivated in a 60 x 60 cm space. Early, midday, and late harvest at 9:00 h, 12:00 h, and 15:00 h were conducted on four different seasons. Fresh and dried leaves were used on the experiments. In order to study the effects of harvest time and drying, yields of dry and fresh herbage (kg/ha), moisture content ( percent), volatile oil content ( percent) and yield (L/ha), and chemical composition of the volatile oil were measured. Seasonal changes had significant effect on yield of fresh herbage, yield and volatile oil content. Maximum volatile oil yields were observed at 9:00 during summer, winter, and spring. Volatile oil content was influenced by season and drying, but not influenced by harvest time.


Citronela de Java (Cymbopogon winterianus Jowitt) pertence à família Poaceae. Óleo volátil de citronela de Java apresenta atividade repelente, antimicrobiana e acaricida. Sabe-se que fatores agronômicos têm grande efeito sobre a qualidade e quantidade de metabólitos essenciais. Por isso é importante a determinação dos níveis ótimos dos fatores agronômicos que afetem o crescimento e a produção. Horário de colheita e secagem são fatores agronômicos muito importantes. O presente estudo foi conduzido na Fazenda Experimental do Departamento de Engenharia Agronômica da Universidade Federal de Sergipe, no período de 2002-2003, usando o delineamento de blocos casualizados e um experimento em esquema fatorial com três repetições. O capim citronela foi cultivado usando espaçamento de 60 cm entre linhas e 60 cm entre plantas. Realizaram-se colheitas de manhã, meio dia e à tarde, às 9:00 h, 12:00 h e 15:00 h, nas quatro estações do ano. Usaram-se folhas frescas e secas no experimento. Para estudar os efeitos do horário de colheita e secagem avaliaram-se as seguintes características: rendimento de biomassa seca e fresca (kg/ha), umidade ( por cento), teor ( por cento) e rendimento (L/ha) de óleo essencial, e a composição química do óleo essencial. Mudanças sazonais apresentaram efeito significativo sobre o rendimento de biomassa fresca e seca, e teor e rendimento de óleo. Rendimentos máximos de óleo essencial foram observados às 9:00 h durante o verão, inverno e primavera. O teor de óleo essencial foi influenciado pela estação doa ano e secagem, mas não foi influenciado pelo horário de colheita.


Sujets)
Production végétale , Cymbopogon/composition chimique , Huile essentielle , Poaceae/composition chimique
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