In vitro antimalarial activity of Syzygium cumini fruit fraction.

Background: Malaria is still one of the most severe public health problems worldwide. The development of treatment, prevention, and control of malaria is one of the substantial problems in the world. Aims: To investigate the in vitro antimalarial activity of Syzygium cumini methanol fruit fraction. Methods: Syzygium cumini L fruit powder was macerated with methanol (PA) and the extract obtained was fractionated using the liquid-liquid partition method with n-hexane, ethyl acetate, butanol, chloroform, methanol, and water solvents. In vitro antimalarial assay was conducted using the culture of Plasmodium falciparum 3D7 strain culture that had reached >5% growth and was examined for IC50 values using a 24-well microplate in duplicate. Each treatment and control well contained 1,080 µl of complete media. Well, number 1 was added with 120 µl fraction, and then the solution was diluted until it reached 0.01, 0.1, 1, 10, and 100 µg/ml the final concentration in the microtiter well. The control only contained complete media and infected erythrocytes without the addition of anti-malarial drugs. The microplate was incubated for 48 hours. After 48 hours, a thin blood smear was made fixed with methanol and stained with 20% Giemsa for 20 minutes to determine the IC50 value by plotting sample concentrations and percentage of parasitemia in Excel. Results: The IC50 values of ethyl acetate fraction, n.hexane fraction, butanol fraction, and water fraction were 1.189, 76.996, 1,769, and 15.058 µg/ml, respectively. Whereases the IC50 values of C1 fraction (mix fraction from chloroform: methanol 100:0 and 90:10) and C4 fraction (mix fraction from chloroform: methanol 20:80, 10:90, and 0:100) were 100.126 and 1.015 µg/ml, respectively. The results showed that the IC50 value of ethyl acetate, butanol, and C4 fraction were lower than 10µg/ml and were considered as good activity (strong antimalarial activity). Conclusion: The ethyl acetate, butanol and C4 subfraction from S. cumini fruit have the potential to be developed as an antimalarial agent.

Phytochemical Analysis and hypoglycemic potential of Filago hurdwarica (Wall. ex DC.) Wagenitz in alloxan induced diabetic mice.

Plants have profound therapeutic benefits, more economical treatments, fewer side effects, and a relatively cheap cost, making them a source of drugs for protective, preventative, curative, or conducive purposes and creating novel phytomedicines. Plant derived medicines are relatively safe compared to synthetic medicines. Many plants have proved to successfully aid in the treatment of diabetes including Filago hurdwarica (Wall. ex DC.) Wagenitz. The current investigations were therefore designed to assess the phytochemical, antioxidant, antidiabetic, and antihyperlipidemic activities of F. hurdwarica. The phytochemical investigations and antioxidant activities of different extracts were carried out using standard chemical tests, DPPH, and H2O2 scavenging assays. F. hurdwarica plant extract in Hydromethanolic solution were prepared by Soxhletation method and stored in refrigerator at 4°C for two days before use. Swiss Albino mice were made diabetic by a single dose of alloxan (150 mg/kg). Hydromethanolic plant extract and fractions of F. hurdwarica were screened for antidiabetic activity and given to the alloxan-induced diabetic mice at a concentration of 150-250 mg/kg of body weight in different groups of 6 diabetic mice each orally once a day for 15 days. Glibenclamide is also given to another group to as a standard drug to support the result at a dose of 10 mg/kg of body weight orally once a day for 15 days. Blood glucose levels and body weights of mice were measured on 0, 4, 7, 11 and 15th days. The study found that the extract was safe up to the dose level of 2000 mg/kg and the dose response effect of chloroform extract (150-250 mg/kg) of F. hurdwarica showed expressive antihyperglycemic effects and also improved other altered biochemical parameters associated with diabetes. The FTIR and XRD spectra demonstrated the occurrence of phenols, alcohols, alkenes, alkyl halides, ketones, and aromatic compounds and confirmed the amorphous nature of the extract. GC-MS spectral analysis showed the tentative presence of 31 phytochemical constituents in the chloroform extract of F. hurdwarica with different retention time. To conclude, the chloroform extract (250 mg/kg) of F. hurdwarica revealed considerable antioxidant, antihyperglycemic, and antihyperlipidemic potential and is safe for treating diabetes and related complications.

Phytochemical Analysis, Total Phenolic, Flavonoid Contents, and Anticancer Evaluations of Solvent Extracts and Saponins of H. digitata.

Cancer is one of the most challenging diseases in the modern era for the researchers and investigators. Extensive research worldwide is underway to find novel therapeutics for prevention and treatment of diseases. The extracted natural sources have shown to be one of the best and effective treatments for cell proliferation and angiogenesis. Different approaches including disc potato model, brine shrimp, and chorioallantoic membrane (CAM) assay were adopted to analyze the anticancer effects. Habenaria digitata was also evaluated for MTT activity against NIH/3T3 cell line. The dexamethasone, etoposide, and vincristine sulfate were used as a positive control in these assays. All of the extracts including crude extracts (Hd.Cr), saponin (Hd.Sp), n-hexane (Hd.Hx), chloroform (Hd.Chf), ethyl acetate (Hd.EA), and aqueous fraction (Hd.Aq) were shown excellent results by using various assays. For example, saponin and chloroform have displayed decent antitumor and angiogenic activity by using potato tumor assay. The saponin fraction and chloroform were shown to be the most efficient in potato tumor experiment, demonstrating 87.5 and 93.7% tumor suppression at concentration of 1000 µg/ml, respectively, with IC50 values of 25.5 and 18.3 µg/ml. Additionally, the two samples, chloroform and saponins, outperformed the rest of the test samples in terms of antiangiogenic activity, with IC50 28.63 µg/ml and 16.20 µg/ml, respectively. In characterizing all solvent fractions, the chloroform (Hd.Chf) and saponin (Hd.Sp) appeared to display good effectiveness against tumor and angiogenesis but very minimal activity against A. tumefaciens. The Hd.Chf and Hd.Sp have been prospective candidates in the isolation of natural products with antineoplastic properties.

Antiapoptotic and antioxidative efficacy of rhizomes of Curcuma amada on the management of diabetes-induced male infertility in albino rat: An effective fraction selection study.

Men with diabetes have negative effects on reproduction that causes sexual dysfunction. Medicinal plants are non-toxic and much safer than synthetic drugs because regular use of synthetic drugs shows long-term side effects. Curcuma amada (Roxb) is a medicinal plant used in Ayurveda and Unani medicinal systems in India. The goal of this study is to rummage the potential efficiency of the most potent solvent fraction of effective extract of hydro-methanol 60:40 of C. amada rhizome on male gonadal hypofunction in streptozotocin-induced diabetic rat. Diabetes-induced testicular hypofunction was evaluated by glycemic, spermiological, biochemical, genomic, flow cytometric, and histology of testicular tissue. The n-hexane, chloroform, ethyl-acetate, and n-butanol solvent fractions of the said extract were administrated for 4 weeks at 10 mg dose/100 g body weight/day. Among all the used fractions, the ethyl-acetate solvent fraction-treated group showed maximum recovery in serum insulin (177.42%), sperm count (92.84%), sperm motility (97.15%), and serum testosterone (164.33%). The diabetic rats treated with ethyl-acetate solvent fraction also exhibited the maximum resettlement in flow cytometric analysis of sperm viability (55.84%) and sperm mitochondrial integrity (149.79%), gene expression patterns of key markers for androgenesis (Δ5, 3ß-HSD 87.50%, and 17ß-HSD 74.66%) and apoptosis (Bax 44.63%, Bcl-2 54.03%, and Caspase-3 35.77%) along with testicular histology. The ethyl-acetate fraction contains alkaloids, flavonoids, and polyphenols where all of these components are not present in other fractions, may be the most effective cause for the recovery of diabetes-linked oxidative stress-mediated testicular hypofunctions. PRACTICAL APPLICATIONS: Nowadays worldwide, the use of synthetic drugs are reduced due to their toxic effect. At present, synthetic drugs are replaced by several herbal drugs, the natural source of medicine which has many therapeutic values. C. amada has strong antioxidant activity due to the presence of bio-active compound(s) that can able to manage streptozotocin-induced diabetes linked to oxidative damage of male gonadal organs. Therefore, these bio-active compound(s)-containing said medicinal plant may use as a good source of antioxidative food in the food industry as nutraceuticals and in pharmaceutical industries for the development of the herbal drug to manage diabetes-linked male gonadal hypofunctions. At present, WHO also gives emphasis for developing one drug-multi-disease therapy. From such a viewpoint, this active fraction-containing phytomolecules may have corrective efficacy against diabetes as well as oxidative stress-linked testicular complications.

[Investigation of the Anti-Leishmanial Effects of Prangos ferulacea and Ferula orientalis Extracts Collected from Sirnak Province Against Leishmania tropica Isolated in Turkey]. / Sirnak Ili ve Çevresinden Toplanan Prangos ferulacea ve Ferula orientalis Ekstrelerinin Türkiye'den Izole Edilmis Leishmania tropica'ya Karsi Anti-Leishmanial Etkilerinin Arastirilmasi.

Leishmaniasis is a vector-borne disease that is caused by the protozoa of Leishmania genus. Leishmaniasis is endemic in tropical, subtropical, and large areas of the Mediterranean basin, and covers a total of 98 countries worldwide. It is estimated, according to the World Health Organization (WHO) data, that approximately 350 million people are at risk in these areas, and approximately 12 million people are infected. Increased drug resistance has been documented lately, in the treatment of leishmaniasis which causes almost 1.2 million new cases annually. Thus, interest in plant-derived active substances has increased in recent years, and new anti-leishmanial agents are investigated with in vitro studies. The aim of the present study was to investigate the anti-leishmanial effects of Prangos ferulacea and Ferula orientalis plant extracts collected from the rural areas of Sirnak province against Leishmania tropica. The water, chloroform, and ethanol extracts of the roots, stems, and fruits of P.ferulaceae and F.orientalis plants were obtained, and the cytotoxic activity tests of the extracts were performed. L.tropica isolate obtained from the Parasite Bank in Manisa Celal Bayar University in Turkey (MHOM/TR/2012/CBCL-LT) was grown on NNN and RPMI 1640 broth medium. The cytotoxicity of each extract on the L.tropica isolate was evaluated with the XTT test. Amphotericin B (AmpB) was used as the positive control, and the IC50 values were determined. The lowest IC50 values of the plant extracts were found to be as follows: P.ferulaceae root chloroform extract 36 µg/ml and fruit chloroform extract 20 µg/ml, F.orientalis root ethanol extract 2.5 µg/ml, and fruit ethanol extract 48 µg/ml, stem chloroform extract 24 µg/ml, and fruit chloroform extract 3.1 µg/ml. It was also determined in our study that only P.ferulaceae root ethanol extract showed cytotoxic activity on the WI-38 fetal lung fibroblast cell line at 65.19 µg/ml at 72 hours. This is the first study that assessed the anti-leishmanial activities of P.ferulaceae and F.orientalis plants that grow in high altitude areas of our country. It was determined that P.ferulaceae root ethanol extract and fruit chloroform extract had the lowest IC50 values among the 18 plant extracts that we examined for their anti-leishmanial activities. The outcomes of this study will be useful in further studies for the determination of active compounds in P.ferulaceae and F.orientalis plant extracts.

Evaluation of the protective effects of Ganoderma applanatum against doxorubicin-induced toxicity in Dalton's Lymphoma Ascites (DLA) bearing mice.

The toxic side effects of doxorubicin in cancer treatment are well established. Here we show that methanolic extract of the fungus Ganoderma applanatum offers protection against cardio- and hepatotoxicity induced by doxorubicin (DOX) in Dalton's Lymphoma Ascites (DLA) bearing mice. Treatment of DLA mice with 20 mg/kg of doxorubicin significantly increased the activities of serum toxicity markers including aspartate amino-transferase (AST), alanine amino-transferase (ALT) and lactate dehydrogenase (LDH). However, co-administration of doxorubicin (20 mg/kg) by intraperitoneal injection and G. applanatum (150 mg/kg) by oral gavage in DLA mice lowered the AST, ALT, and LDH activities when compared to DOX alone treatment. Treatment of DLA mice with DOX alone resulted in reduced GSH contents, and decreased the activities of glutathione-s-transferase (GST), catalase (CAT), and superoxide dismutase (SOD). Treatment of DOX-administered DLA mice with G. applanatum however increased the GSH content and elevated the activities of GST, CAT, and SOD. Among the various solvent extracts of G. applanatum, methanolic extract showed the highest phenolic (376.5 ± 15.24 mg GAE/g) and flavonoid (4717.79 ± 170.22 mg quercetin/g) contents compared to the aqueous (216.3 ± 7.33 mg GAE/g) and chloroform extracts (137.27 ± 1.03 mg GAE/g). Consistently, the methanolic extract was found to possess the highest free radical scavenging activities when compared to the aqueous and chloroform extracts as measured by ABTS and DPPH assays. Our results thus suggest that the protective roles of G. applanatum in DOX-induced toxicity could be an attribute of the antioxidant properties conferred by the high phenolic and flavonoid contents.

Phytochemical Investigation and Therapeutical Potential of Cotinus coggygria Scop. in Alloxan-Induced Diabetic Mice.

Plants are a significant source for the development of new phytomedicines due to their great clinical benefits, efficiency, cost-effectiveness, fewer side effects, and more affordable therapies. Numerous plants used in traditional treatments, such as Cotinus coggygria Scop., have been effective in the treatment of diabetes mellitus (DM). Therefore, the study is aimed at assessing the phytochemical, antioxidant, and antidiabetic properties of C. coggygria. The hypoglycemic and hypolipidemic activity was evaluated in Swiss male Albino mice by administering an oral dose of 150-250 mg/kg of C. coggygria extracts in alloxan-induced diabetic mice for 15 days. The antioxidant activity and phytochemical composition of the extracts were assessed by using α, α diphenyl-ß-picrylhydrazyl (DPPH) and hydrogen peroxide scavenging assays and through standard chemical procedures. The effects of extracts on blood glucose, body weight, lipid profile, and biochemical parameters like total cholesterol (TC), triglyceride (TG), low-density lipids (LDL), high-density lipids (HDL), plasma insulin, liver glycogen, aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), urea, and creatinine were determined according to standard procedures. The activities of antioxidant enzymes such as superoxide-dismutase (SOD), peroxidase (POD), and catalase (CAT) were also analyzed spectrophotometrically. The hypoglycemic and hypolipidemic effects with chloroform extracts of 250 mg/kg were found significant in the treatment of diabetes in alloxanised mice compared to the diabetic group. The haematological parameters such as TC, TG, HDL, LDL, creatinine, urea, AST, ALT, and ALP were significantly improved (p < 0.01) by the chloroform extract of 250 mg/kg compared to the diabetic group. Treatment for 15 days showed significant elevation (p < 0.01) of antioxidant enzymes. Fourier-transform infrared spectroscopic (FTIR) and gas chromatography-mass spectrometry (GC-MS), column chromatography (CC), and nuclear magnetic resonance (NMR) analyses tentatively identified different phytoconstitutents and metabolites in C. coggygria leaves, which have been reported to possess antihyperglycemic properties. In conclusion, the chloroform extract of 250 mg/kg of C. coggygria possesses significant hypoglycemic and hypolipidemic potential which may prove the claimed use of the plant in amelioration of diabetes and associated complications in folkloric medicine. Additional studies are required for the purification, characterization, and structural elucidation of bioactive compounds.

Lawsonia Inermis Markedly Improves Cognitive Functions in Animal Models and Modulate Oxidative Stress Markers in the Brain.

Background and Objective: Medicinal plants represent an important source of alternative medicine for the management of various diseases. The present study was undertaken to assess the potential of Lawsonia inermis ethanol (Li.Et) and chloroform (Li.Chf) extracts as memory-enhancing agents in experimental animals. Materials and Methods: Li.Et and Li.Chf were phytochemically characterized via gas chromatography-mass spectroscopy (GC-MS). Samples were tested for nootropic potentials at doses of 25, 50, 100, 200 mg/kg (per oral in experimental animals (p.o.)). Swiss albino mice of either sex (n = 210) were divided into 21 × 10 groups for each animal model. Memory-enhancing potentials of the samples were assessed using two methods including "without inducing amnesia" and "induction of amnesia" by administration of diazepam (1 mg/kg, intraperitoneally. Piracetam at 400 mg/kg (i.p.) was used as positive control. Cognitive behavioral models including elevated plus maze (EPM) and the passive shock avoidance (PSA) paradigm were used. Biochemical markers of oxidative stress such as glutathione (GSH), catalase (CAT), superoxide dismutase (SOD) levels were analyzed in the brain tissue of treated mice. Results: In 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radicals scavenging assay, Li.Et and Li.Chf exhibited 70.98 ± 1.56 and 66.99 ± 1.76% inhibitions respectively at 1.28 mg/mL concentration. GCMS results revealed the presence of important phytochemicals. Both samples (Li.Et and Li.Chf) at 25 mg/kg (p.o.) dose significantly (p < 0.05) improved learning and memory as indicated by decline in transfer latency and increase in step down latency in EPM and PSA models respectively. Li.Et and Li.Chf at 25 mg/kg (p.o.) showed considerable increase in GSH (2.75 ± 0.018 ***), SOD (2.61 ± 0.059 ***) and CAT (2.71 ± 0.049 ***) levels as compared to positive and negative control groups. Conclusions: This study provides the preliminary clue that L. inermis may be a potential source of memory-enhancing and anti-oxidant compounds and thus warrant further studies.

For treatment of odontogenic keratocysts, is enucleation, when compared to decompression, a less complex management protocol?

PURPOSE: To determine whether the clinical management of odontogenic keratocysts (OKCs) is more complex in patients who undergo enucleation with or without adjuvant therapy than in patients who undergo decompression with or without residual cystectomy. MATERIALS AND METHODS: The authors implemented a retrospective cohort study and enrolled a sample composed of patients presenting for the evaluation and management of OKCs. The predictor variable was treatment group, classified as decompression with or without residual cystectomy versus enucleation with or without adjuvant therapy (Carnoy solution, cryotherapy, or peripheral ostectomy). The outcome variables were measurements of complexity of management, including total number of procedures, venue of procedure (operating room vs office), type of anesthesia, hospital admissions, and total number of follow-up visits. Data analyses were performed using univariate and bivariate statistics and a multiple linear regression model. RESULTS: The study sample was composed of 45 patients (66 OKC lesions) with a mean age of 43.3 years. Of the 66 OKCs treated, 34 (51.5%) were treated with decompression with or without residual cystectomy and 32 (48.5%) were treated with enucleation with or without adjunctive therapy. Larger lesions and lesions with radiographic evidence of cortical perforation were treated more often with decompression with or without residual cystectomy. Based on the multiple linear regression model, patients who underwent enucleation with or without adjuvant therapy compared with those who underwent decompression with or without residual cystectomy had on average 1) 1.1 fewer total procedures (P < .01), 2) 0.8 fewer total office procedures (P < .01), 3) 0.6 fewer local anesthesia procedures (P < .01), and 4) 4.8 fewer postoperative visits (P < .01). There was no difference in the number of general anesthesia procedures, office sedation procedures, or hospital admissions. CONCLUSION: Given comparable recurrence rates, the increased complexity of managing OKCs with decompression with or without residual cystectomy might not be warranted. Enucleation with or without adjunctive therapy could be the more efficient treatment option.

Early drug discovery and the rise of pharmaceutical chemistry.

Studies in the field of forensic pharmacology and toxicology would not be complete without some knowledge of the history of drug discovery, the various personalities involved, and the events leading to the development and introduction of new therapeutic agents. The first medicinal drugs came from natural sources and existed in the form of herbs, plants, roots, vines and fungi. Until the mid-nineteenth century nature's pharmaceuticals were all that were available to relieve man's pain and suffering. The first synthetic drug, chloral hydrate, was discovered in 1869 and introduced as a sedative-hypnotic; it is still available today in some countries. The first pharmaceutical companies were spin-offs from the textiles and synthetic dye industry and owe much to the rich source of organic chemicals derived from the distillation of coal (coal-tar). The first analgesics and antipyretics, exemplified by phenacetin and acetanilide, were simple chemical derivatives of aniline and p-nitrophenol, both of which were byproducts from coal-tar. An extract from the bark of the white willow tree had been used for centuries to treat various fevers and inflammation. The active principle in white willow, salicin or salicylic acid, had a bitter taste and irritated the gastric mucosa, but a simple chemical modification was much more palatable. This was acetylsalicylic acid, better known as Aspirin®, the first blockbuster drug. At the start of the twentieth century, the first of the barbiturate family of drugs entered the pharmacopoeia and the rest, as they say, is history.

Comparative SEM evaluation of three solvents used in endodontic retreatment: an ex vivo study.

This study compared, by scanning electron microscopy (SEM), the efficacy of three solvents on the removal of filling materials from dentinal tubules during endodontic retreatment. Forty human maxillary canines with straight canals were prepared according to a crown-down technique and enlarged to a#30 apical file size, before obturation with gutta-percha and a zinc-oxide-eugenol based sealer. The samples were stored for 3 months before being randomly assigned to four groups: chloroform (n=10), orange oil (n=10), eucalyptol (n=10) and control (n=10). Solvents were applied to a reservoir created on the coronal root third using Gates Glidden drills. The total time for retreatment using the solvents was 5 minutes per tooth. Following retreatment the roots were split longitudinally for SEM evaluation. SEM images were digitized, analyzed using Image ProPlus 4.5 software, and the number of dentinal tubules free of filling material from the middle and apical thirds was recorded. No significant difference was found among the solvent groups regarding the number of dentinal tubules free of root filling remnants in the middle and apical root thirds (p>0.05). However, the control group had fewer dentinal tubules free of filling material (p<0.05). Under the tested conditions, it may be concluded that there was no significant difference among the solvents used to obtain dentinal tubules free of filling material remnants.

Valores de trihalometanos en agua de consumo de la provincia de Granada, España / Trihalomethane levels in drinking water in the province of Granada [Spain]

Objetivos: La cloración del agua da lugar a la formación desubproductos potencialmente dañinos para la salud, entre elloslos trihalometanos, que se han hallado elevados en algunaszonas de España. En este estudio se investigan los valoresde trihalometanos en el agua de consumo suministrada porvarios sistemas de abastecimiento de la provincia de Granada,en el área de actuación de la cohorte madres-hijos de laRed INMA (Infancia y Medio Ambiente).Métodos: Se analizaron 82 muestras de agua de consumoen dos campañas de muestreo en invierno y verano de 2006.Se determinó la concentración de cloroformo, bromodiclorometano,dibromoclorometano y bromoformo, siguiendo un procedimientooptimizado basado en cromatografía de gases yespectrometría de masas.Resultados: El rango de concentración de trihalometanos totalesse situó entre 0,14 y 18,75 g/l en la campaña de inviernoy entre 0,01 y 31,87 g/l en la de verano. El compuestomayoritario fue cloroformo. La concentración media de trihalometanosen agua de origen superficial y subterráneo fue de10,13 y 1,41 g/l, respectivamente.Conclusiones: Los valores de trihalometanos encontradosson muy inferiores a la concentración máxima admisible (100g/l) establecida por la Unión Europea para estos compuestos.Estos valores varían significativamente según el origendel agua, con mayores concentraciones en áreas urbana ysemiurbana, donde el agua es mayoritariamente de origen superficial.La presencia de trihalometanos en la zona es menora la descrita en otras regiones españolas(AU)

Objectives: Drinking water chlorination generates potentiallyharmful by-products, such as trihalomethanes. Trihalomethanelevels are high in some parts of Spain. The aim of the presentstudy was to investigate trihalomethane concentrationsin drinking water from distinct water supplies in the provinceof Granada, within the framework of the Childhood and Environment(INMA) study.Methods: Eighty-two tap water samples were collected in twocampaigns during the winter and summer of 2006. An optimizedprocedure based on gas chromatography and massspectrometry was used to determine concentrations of chloroform,bromodichloromethane, dibromochloromethane, andbromoform in the samples.Results: Total trihalomethane concentrations ranged from 0.14to 18.75 g/l in winter samples and from 0.01 to 31.87 g/lin summer samples. The most abundant compound waschloroform. Mean trihalomethane concentrations were 10.13in surface waters and 1.41 g/l in ground waters.Conclusions: The trihalomethane levels found were considerablybelow the maximum permitted level of 100 g/l in the European Union. The values obtained varied widely accordingto the type of water source: the highest concentrations werefound in urban and sub-urban areas, where the water is largelyof surface origin. The presence of trihalomethanes waslower than that reported in other Spanish regions(AU)

Comparative sem evaluation by of three solvents used in endodontic retreatment: an ex vivo study

This study compared, by scanning electron microscopy (SEM), the efficacy of three solvents on the removal of filling materials from dentinal tubules during endodontic retreatment. Forty human maxillary canines with straight canals were prepared according to a crown-down technique and enlarged to a#30 apical file size, before obturation with gutta-percha and a zinc-oxide-eugenol based sealer. The samples were stored for 3 months before being randomly assigned to four groups: chloroform (n=10), orange oil (n=10), eucalyptol (n=10) and control (n=10). Solvents were applied to a reservoir created on the coronal root third using Gates Glidden drills. The total time for retreatment using the solvents was 5 minutes per tooth. Following retreatment the roots were split longitudinally for SEM evaluation. SEM images were digitized, analyzed using Image ProPlus 4.5 software, and the number of dentinal tubules free of filling material from the middle and apical thirds was recorded. No significant difference was found among the solvent groups regarding the number of dentinal tubules free of root filling remnants in the middle and apical root thirds (p>0.05). However, the control group had fewer dentinal tubules free of filling material (p<0.05). Under the tested conditions, it may be concluded that there was no significant difference among the solvents used to obtain dentinal tubules free of filling material remnants.