Clostridium perfringens α and ß recombinant toxoids in equine immunization / Toxóides recombinantes α e ß de Clostridium perfringens na imunização de equinos

Clostridium perfringens is considered one of the main causative agents of superacute enterocolitis, usually fatal in the equine species, due to the action of the ß toxin, and is responsible for causing severe myonecrosis, by the action of the α toxin. The great importance of this agent in the equine economy is due to high mortality and lack of vaccines, which are the main form of prevention, which guarantee the immunization of this animal species. The aim of this study was to evaluate three different concentrations (100, 200 and 400µg) of C. perfringens α and ß recombinant toxoids in equine immunization and to compare with a group vaccinated with a commercial toxoid. The commercial vaccine was not able to stimulate an immune response and the recombinant vaccine was able to induce satisfactory humoral immune response in vaccinated horses, proving to be an alternative prophylactic for C. perfringens infection.(AU)

Clostridium perfringens é considerado um dos principais agentes causadores de enterocolites superagudas, geralmente fatais na espécie equina, devido à ação da toxina ß, além de ser responsável por causar quadros graves de mionecrose, pela ação da toxina α. A grande importância desses agentes na equinocultura, deve-se a elevada mortalidade e a inexistência de vacinas, principal forma de prevenção, que garantam a imunização dessa espécie animal. O objetivo deste trabalho foi avaliar três diferentes concentrações (100, 200 e 400µg) dos toxóides recombinantes α e ß de C. perfringens na imunização de equinos, bem como comparar com um grupo vacinado com um toxóide comercial. A vacina comercial não se mostrou capaz de estimular uma resposta imune e a vacina recombinante foi capaz de induzir resposta imune humoral satisfatória em equinos vacinados, provando ser uma alternativa profilática para infecção por C. Perfringens.(AU)

Toxinotyping of Clostridium perfringens in Poultry from Necrotic Enteritis Cases

Clostridium perfringens is well known causative agent of necrotic enteritis in poultry and is mainly caused by Type A toxin. NetB toxin is found to be one of the newly emerging virulent toxin gene which is also responsible for necrotic enteritis. The present study was carried out to characterize and to type the different toxins associated with C. perfringens in NE cases of poultry. For the present study total 125 samples were collected from poultry birds, out of which 50 samples were of intestinal content from diseased birds, 50 cloacal swabs and 25 intestinal content from healthy birds. These samples were further processed for isolation, identification, and toxinotyping of Clostridium perfringens isolates. Onisolation of C. perfringens on blood agar total 43 isolates were found positive showing a pattern of double hemolysis on blood agar. The positive isolates of C. perfringens were further confirmed by using 16S rRNA species specific PCR. After confirmation isolates were processed for toxinotyping mainly targeting cpa, cpb and cpb2 toxins by using multiplex PCR. On toxinotyping it was found that NE in poultry birds were mainly caused by C. perfringens type A. On virulent gene detection of netB toxin, total 4 isolates were found positive for netB toxin. This study pointed out that C. perfringens type A is responsible for development of NE in poultry along with net B toxin which is a new key virulent factor. Further studies of netB toxoid and C. perfringens type A for vaccine production could minimize the clostridial problems in broiler farms

Sudden death caused by Clostridium perfringens sepsis presenting as massive intravascular hemolysis

An 80-year-old Japanese woman with diabetes mellitus was admitted with gastrointestinal symptoms and pyrexia. At presentation, liver abscesses and severe hemolytic anemia were noted. Before detailed diagnostic evaluation and adequate treatment, she suddenly died 2.5 hours after admission. The autopsy and bacteriological examinations revealed liver abscesses and massive intravascular hemolysis caused by Clostridium perfringens as well as other miscellaneous critical pathological findings, including acute renal tubular necrosis, lung edema, and pulmonary fat embolism. In this article, the detailed autopsy results are described and clinicopathologic characteristics on Clostridium perfringens-related sudden death are discussed with a review of the literature.

Necrohemorrhagic enteritis outbreak in a cattle feedlot in Nova Crixás, Goiás, Brazil / Surto de enterite necro-hemorrágica em um confinamento de bovinos no município de Nova Crixás, Goiás, Brasil

This study described an outbreak of necrohemorrhagic enteritis in a beef cattle feedlot in Nova Crixás, State of Goiás, Brazil, with emphasis on epidemiological, lesional, and laboratory aspects. Visits to the property were carried out and a necroscopic examination was performed on the bovine cadavers (N=57), which presented similar macroscopic alterations. Epidemiological data were collected, mainly referring to the feeding management of animals, and tissue samples were submitted to histopathological examination. Samples of feces and intestinal contents were also collected for bacterial isolation and PCR genotyping to detect the etiological agent, being confirmed Clostridium perfringens type A strains in 100% of the samples. Furthermore, 33.3% of strains isolated from intestinal contents and 40% of those isolated from feces were positive for beta-2 encoding gene. Considering the history, macroscopic and microscopic findings, as well as bacterial isolation and PCR, the diagnosis of bovine necrohemorrhagic enteritis was determined.(AU)

Descreve-se um surto de enterite necro-hemorrágica em um confinamento de bovinos de corte no município de Nova Crixás, Estado de Goiás, Brasil, com ênfase nos aspectos epidemiológicos, lesionais e laboratoriais. Foram realizadas visitas à propriedade e todos os cadáveres bovinos (N=57) foram submetidos ao exame necroscópico, os quais apresentaram alterações macroscópicas semelhantes. Foram compilados dados epidemiológicos, sobretudo referentes ao manejo alimentar dos animais e amostras de tecido foram submetidas a exame histopatológico. Foram colhidas, também, amostras de fezes e conteúdo intestinal para isolamento bacteriano e genotipagem por PCR para detecção do agente etiológico, sendo confirmadas estirpes de Clostridium perfringens tipo A em 100% das amostras. Ainda, 33,3% das cepas de Clostridium perfringens isoladas no conteúdo intestinal e 40% daquelas isoladas nas fezes foram positivas para o gene codificador da toxina beta-2. Considerando o histórico, os achados macroscópicos e microscópicos, o isolamento bacteriano e o PCR, foi estabelecido o diagnóstico de enterite necro-hemorrágica por C. perfringens tipo A.(AU)

Comparative studies on the efficacy of lincomycin and bacitracin for the control of necrotic enteritis in broiler chickens

Background: The present study was conducted to evaluate the efficacy of lincomycin and/or bacitracin for control of experimentally-induced Clostridium perfringens (CP) infection in broiler chickens.Methods: A total of 100 one-day-old Cobb-mixed chicks were divided into five groups (A, B, C, D and E, each of 20 bird). At the 15th day of age, all birds (except group A) were inoculated orally with CP broth culture (109 CFU/mL). Two days later, drugs were orally administered once daily for five consecutive days as follow; Group A and B were left untreated. Group C, D, and E were treated with lincomycin (0.5 g/l), bacitracin (100 mg/l), lincomycin and bacitracin, respectively. The efficacy of used drugs was estimated based on clinical symptoms, body weight, weight gain, feed conversion rate. Hematobiochemical changes were also determined.Results: Necrotic enteritis in broiler chickens induced a significant decrease in body weight, weight gain, erythrocytic count, hemoglobin content, PCV %, serum proteins, catalase, and superoxide dismutase. Additionally, a marked decrease in serum lipids was obtained. Furthermore, a significant increase in feed conversion rate, leukocytic count, phagocytic activity, phagocytic index, serum total globulin, ? globulin and malondialdehyde coupled with a marked increase in ? and ? globulins were determined. Medication of infected broilers with lincomycin and/or bacitracin improved clinical signs and reduced mortality rate to 8, 6 and 2%, respectively, as well as restored the performance and hematobiochemical alterations.Conclusions: a combination of lincomycin and bacitracin was of considerable value for the control of necrotic enteritis in broiler chickens.

Molecular detection and antimicrobial resistance of Clostridium perfringens isolated from diabetic patients and bullet wounds

Clostridium perfringens is a major cause of gas gangrene. The morbidity of C. perfringens is connected with producing toxins. This cross-sectional study was designed to isolate, genetically diagnose, and study the antibiotic susceptibility patterns of C. perfringens isolated from clinical samples. Different wound swabs (from diabetic patients, cellulitis, and bullet wounds) were taken from 140 patients. For isolation of anaerobic bacteria, samples (in thioglycolate broth) were immediately incubated anaerobically then identified according to the cultural properties and biochemical tests. DNA was extracted from all specimens. Polymerase chain reaction was applied for detection of 16SrRNA and internal transcribed spacer (ITS) genes of C. perfringens. The susceptibility of bacterial isolates to different antibiotics was determined using Vitek 2 system and disk diffusion test. Out of 140 clinical samples collected during this study, 3 (2.14%) C. perfringens isolates were recovered of which 2 isolates (1.43%) obtained from diabetic patients and one (0.71%) from bullet wounds. Results also showed that only 7 isolates (5%) were detected by a molecular method using specific primers 16S rRNA and ITS genes of C. perfringens. Results of antibiotic susceptibility testing showed that all isolates were highly susceptible to penicillins and β-lactamase inhibitors, metronidazole, and aminoglycosides. On the other hand, all isolates were highly resistant to tetracycline, levofloxacin, and erythromycin. The susceptibility patterns of C. perfringens isolates showed that all isolates were multidrug resistance. Using the amplification of ITS gene increases specificity and sensitivity (by reducing non-specific annealing and primer dimer formation) which increases the probability of detection of suspected C. perfringens isolates.

Advances in the study of the relationship between optic neuromyelitis and clostridium perfringens / 解放军医学杂志

Neuromyelitis optica is an autoimmune astrocytopathy of the central nervous system mainly characterized by recurrent episodes of optic neuritis and acute transverse myelitis. Although the exact etiology and pathogenesis of NMO remain to be established, complex interactions between genetic and environmental factors are thought to be involved in its development. Studies have shown that the pathogenesis of NMO is closely related to gut microbiome, and the content of clostridium perfringens in gut microbiome of NMO patients was significantly increased. This article mainly reviews the correlation between the neuromyelitis optica and clostridium perfringens, in order to further clarify the pathogenesis of NMO and provide reference for clinical treatment.

Advances in the application of claudins to tumor therapy / 生物工程学报

Claudin proteins are the most crucial components of tight junctions, and play an essential role in maintaining cell polarity, regulating cell permeability and the intercellular ion. In recent years, many studies have shown that abnormality of claudins expression is implicated in the tumor progression. The expression correlates with tumor prognosis and can serve as a biomarker of prognosis and potential therapeutic targets. This review summarizes the current knowledge regarding claudin dysregulation in cancer and highlights the progress in claudin-based treatments.

Choque séptico fulminante neonatal por Clostridium perfringens / Neonatal fulminant septic shock by Clostridium perfringens

Resumen Clostridium spp. es un bacilo grampositivos, anaerobio, formador de esporas y ampliamente distribuido en el ambiente. Las infecciones por Clostridium perfringens en neonatos son en extremo raras. La sepsis grave por anaerobios, incluyendo el choque séptico, es un evento clínico inusual en este grupo de pacientes. Se reportan dos casos de bacteriemia por C. perfringens asociados a choque séptico fulminante en recién nacidos con enterocolitis necrosante grave.

Abstract Clostridium species are anaerobic, spore, forming gram-positive bacteria that are widely spread in the environment. Clostridium perfringens infections in neonates are extremely rare. Severe anaerobic sepsis, including septic shock, is an unusual clinical event in this group of patients. We highlight two cases of C. perfringens bacteremia associated with fulminant septic shock in neonates with severe necrotizing enterocolitis.

Use of photodynamic inactivation for in vitro reduction of prevalent bacteria in Fournier's Gangrene

ABSTRACT Fournier's Gangrene (FG) is an infectious disease caused by several synergic microbes, with high morbidity and mortality rates; therefore, the search for new less invasive and mutilating treatments, with faster recovery, has been proposed. Surgical intervention, the use of several systemic and topic antibiotics, and hyperbaric oxygen therapy are currently the best approach for the treatment of these patients. The use of Photodynamic Inactivation (PDI) aims to lower morbidity and mortality, by reducing bacterial microbiota and speeding wound healing. In the present study, viable bacteria were separated in four groups: Group L-/F- (no irradiation with red laser and absence of methylene blue photosensitizer), Group L-/F+ (no irradiation with red laser and presence of methylene blue), Group L+/F- (irradiation with red laser and absence of methylene blue) and L+/F+ (irradiation with red laser associated to methylene blue). In all groups, exposure time to treatment was 5, 10 and 15 minutes. The concentration of methylene blue photosensitizer was 0.1mg/L, and the dose of red laser (660nm wave length) was 176.9mW/cm2. Following irradiation, the reduction of number of bacteria was evaluated, and the results were expressed in colony forming units (CFU) and as exponential reduction. As the main results, in the L+/F+ group, there were no Clostridium perfringens and Staphylococcus aureus CFUs and there was a reduction of Escherichia coli that was not observed in the other groups.

Isolation and genotyping of Clostridium perfringens from goats in Minas Gerais, Brazil / Isolamento e genotipagem de Clostridium perfringens isolados de cabras em Minas Gerais, Brasil

ABSTRACT: Despite the known importance of Clostridium perfringens as an enteropathogen in small ruminants, little is known about the role of its additional virulence factors or the frequency of the various C. perfringens genotypes in healthy goats; this complicates the laboratory diagnosis of the infections caused by this microorganism. In light of this, the aim of the present study was to isolate and genotype C. perfringens from stool samples from healthy goats in Brazil. Stool samples from 250 apparently healthy adult goats from 17 different herds in Minas Gerais, Brazil were collected, and isolation and genotyping of C. perfringens was performed. C. perfringens type A was isolated from 189 (75.6%) goats, whereas C. perfringens types C and D were each detected in one goat (0.4%). All isolates were negative for enterotoxin-, NetB-, NetE-, and NetF-encoding genes. These results confirmed C. perfringens type A as part of the microbiota in these animals, and they suggested that C. perfringens type C and D are rarely isolated from healthy goats.

RESUMO: Apesar da reconhecida importância de Clostridium perfringens como enteropatógeno de pequenos ruminantes, pouco se sabe sobre a frequência dos genótipos ou do papel de fatores de virulência adicionais de C. perfringens em cabras saudáveis, dificultando o diagnóstico laboratorial da infecção causada por esse micro-organismo. Dessa forma, o presente estudo teve como objetivo caracterizar C. perfringens de amostras de fezes de cabras adultas saudáveis. Amostras de fezes de 250 cabras saudáveis de 17 rebanhos diferentes em Minas Gerais, Brasil, foram submetidas ao isolamento e genotipagem de C. perfringens. C. perfringens tipo A foi isolado de 189 (75,6%) cabras, enquanto C. perfringens tipos C e D foram detectados em um animal (0.4%) cada. Todos os isolados foram negativos para os genes codificadores das toxinas NetB, NetE, NetF e enterotoxina. Os resultados apresentados confirmam C. perfringens tipo A como parte da microbiota de cabras saudáveis e sugere que C. perfringens tipos C e D são raramente encontrados em caprinos saudáveis.

Microbiological quality of honey from stingless bee, jandaíra (Melipona subnitida), from the semiarid region of Brazil / Qualidade microbiológica do mel da abelha sem ferrão jandaíra (Melipona subnitida) da região semi-árida do Brasil

ABSTRACT: The aim of this study was to evaluate the presence of microorganisms in honey produced by the stingless bee (SB) jandaíra (Melipona subnitida) from the semiarid region of Brazil. Thirty-five samples were analyzed and all of them were positive for mesophilic bacteria, coliforms at 45°C, fungi, and yeast. Staphylococcus spp. were identified in 85.7%, while Bacillus spp. were detected in 34.3% of honey samples. DNAs of Clostridium perfringens and C. botulinum were detected in 40% and 2.8% of the samples, respectively. Salmonella spp. and C. difficile were not detected. The present research revealed a great diversity of microorganisms in honey produced by jandaíra.

RESUMO: O objetivo deste trabalho foi avaliar a presença de microrganismos no mel produzido pela abelha sem ferrão jandaíra (Melipona subnitida). Trinta e cinco amostras foram avaliadas e todas foram positivas para bactérias mesofílicas, coliformes a 45 ºC, fungos e leveduras. Staphylococcus spp. foi identificado em 85,7% enquanto Bacillus foi detectado em 34,3% das amostras de mel. Clostridium perfringens e C. botulinum foram detectados em 40% e 2,8% das amostras respectivamente. Salmonella spp. e C. difficile não foram detectados. O presente trabalho revelou uma grande diversidade de microrganismos no mel produzido por jandaíra.

Determination of multidrug resistance mechanisms in Clostridium perfringens type A isolates using RNA sequencing and 2D-electrophoresis

In this study, we screened differentially expressed genes in a multidrug-resistant isolate strain of Clostridium perfringens by RNA sequencing. We also separated and identified differentially expressed proteins (DEPs) in the isolate strain by two-dimensional electrophoresis (2-DE) and mass spectrometry (MS). The RNA sequencing results showed that, compared with the control strain, 1128 genes were differentially expressed in the isolate strain, and these included 227 up-regulated genes and 901 down-regulated genes. Bioinformatics analysis identified the following genes and gene categories that are potentially involved in multidrug resistance (MDR) in the isolate strain: drug transport, drug response, hydrolase activity, transmembrane transporter, transferase activity, amidase transmembrane transporter, efflux transmembrane transporter, bacterial chemotaxis, ABC transporter, and others. The results of the 2-DE showed that 70 proteins were differentially expressed in the isolate strain, 45 of which were up-regulated and 25 down-regulated. Twenty-seven DEPs were identified by MS and these included the following protein categories: ribosome, antimicrobial peptide resistance, and ABC transporter, all of which may be involved in MDR in the isolate strain of C. perfringens. The results provide reference data for further investigations on the drug resistant molecular mechanisms of C. perfringens.

Contamination and genotyping of Clostridium perfringens from chicken in Macao / 中国人兽共患病学报

We determine the contamination and genotypes of Clostridium perfringens isolated from chickens in Macau.C. perfringens were isolated from these samples by double tube method and then identified by biochemical test.Genotyping of i-solated strains was determined by multiplex PCR.A total of 120 samples,the positive rates were 37.5%,respectively.All of the isolated strains were type A.This study indicated that contamination of C.perfringens type A exists in chicken intestines, fresh chickens and chilled chickens in Macau,and provided reference data for the public health problems caused by C.perfrin-gens.

Prevalence, toxin gene profile, antibiotic resistance, and molecular characterization of Clostridium perfringens from diarrheic and non-diarrheic dogs in Korea

Clostridium perfringens causes diarrhea and other diseases in animals and humans. We investigated the prevalence, toxin gene profiles, and antibiotic resistance of C. perfringens isolated from diarrheic dogs (DD) and non-diarrheic dogs (ND) in two animal hospitals in Seoul, Korea. Fecal samples were collected from clinically DD (n = 49) and ND (n = 34). C. perfringens was isolated from 31 of 49 DD (63.3%) and 21 of 34 ND dogs (61.8%). All C. perfringens strains were positive for the α toxin gene, but not for the β, ε, or ι toxin genes; therefore, all strains were identified as type A C. perfringens. All isolates were cpe-negative, whereas the β2 toxin gene was identified in 83.9% and 61.9% of isolates from DD and ND, respectively. Most isolates were susceptible to ampicillin (94%), chloramphenicol (92%), metronidazole (100%), moxifloxacin (96%), and imipenem (100%). However, 25.0% and 21.2% of isolates were resistant to tetracycline and clindamycin, respectively. Molecular subtyping of the isolated strains was performed by using pulsed-field gel electrophoresis. Fifty-two isolates were classified into 48 pulsotypes based on more than 90% similarity of banding patterns. No notable differences were observed among the isolates from DD and ND.

Clostridium perfringens bacteremia with malignant hematopathy:a case report and review of literatures / 中国感染控制杂志

Infection is an important cause of higher mortality in patients with hematological diseases than healthy people, and fever is often the only indication of the disease.Clostridium perfringens(C.perfringens)is a grampositive anaerobic bacillus of the Clostridiumgenus, it belongs to the normal flora of the intestinal tract and is not pathogenic in normal condition.However, when intestinal flora is imbalanced due to low hypoimmunity of human body or influenced by such factors as diet, medicine, environment and other factors, it can enter the blood and cause bacteremia.At present, it has never been reported that bacteremia was caused by C.perfringens in patients with malignant hematological diseases accompanied by neutropenia, this article reported the diagnosis and treatment of C. perfringens bloodstream in one patient with malignant hematopathy, so as to provide basis for diagnosis and treatment of the disease.

Adhesion and invasion of Clostridium perfringens type A into epithelial cells

ABSTRACT Clostridium perfringens is the causative agent for necrotic enteritis. It secretes the major virulence factors, and α- and NetB-toxins that are responsible for intestinal lesions. The TpeL toxin affects cell morphology by producing myonecrosis, but its role in the pathogenesis of necrotic enteritis is unclear. In this study, the presence of netB and tpeL genes in C. perfringens type A strains isolated from chickens with necrotic enteritis, their cytotoxic effects and role in adhesion and invasion of epithelial cells were evaluated. Six (27.3%) of the 22 C. perfringens type A strains were harboring the tpeL gene and produced morphological alterations in Vero cells after 6 h of incubation. Strains tpeL (-) induced strong cell rounding after 6 h of incubation and produced cell enlargement. None of the 22 strains harbored netB gene. All the six tpeL (+) gene strains were able to adhere to HEp-2 cells; however, only four of them (66.6%) were invasive. Thus, these results suggest that the presence of tpeL gene or TpeL toxin might be required for the adherence of bacteria to HEp-2 cells; however, it could not have any role in the invasion process.

Establishment and preliminary application of multiplex PCR for detecting toxin-typing of goat Clostridium perfringens strains / 中国兽医学报

According 1o the genome sequences of α.β,e,ι toxins of Clostridium perfringens in GenBank,four pairs of primers targeting α,β,ε,ι toxin genes were designed.After the multiplex PCR reaction condition was optimized,the multiplex PCR for identification and toxintyping of C.perfringens strains was developed.The specificity test showed that the expected fragments of C.perfringens reference strains including A.B,C,D,E five toxin types were amplified successfully from genomic DNA of C.perfringens,respectively.However,a band could not be amplified from Clostidrium novyi and Clostridium septicum as negative control groups.The sensitivity test showed that the limit detection of multiplex PCR was 9.0,17.8,12.2,13.8,18.5 pg DNA of A,B,C,D,E five toxin types C.perfringens,respectively.Repetitive testing showed that the established method had a good repeatability.Nine type A strains of and 1 type C strains of C.Perfringens from 21 clinical samples of dead goat were detected by the multiplex PCR developed in this study.This study establishes the multiple PCR method which not only can detect C.perfringens rapidly but also can identify five toxin types of C.perfringens.

Inhibitory effect of Persea cordata Mez. (pau-andrade) bark extracts against Clostridium perfringens causing gangrenous mastitis

Introduction: Gangrenous mastitis is a special clinical presentation of mastitis in cattle and small ruminants. The bark of the tree Persea cordata Mez. is used in Brazilian ethnoveterinary medicine to treat wounds in farm animals. Objectives: Examine in vitro antimicrobial action of apolar fractions of P. cordata bark against a wild strain of C. perfringens isolated from the udder of a cow with gangrenous mastitis, and against a reference strain. Methods: A milk sample was collected from the udder, aliquots were diluted and Gram-stained smears were performed. The aliquots were inoculated in broth and planted in blood agar, and then incubated in anaerobiosis at 37oC / 24h. Biochemical identification was based on bacterial isolation. In vitro inhibitory activity of apolar fractions of P. cordata was evaluated by agar diffusion and MIC (minimum inhibitory concentration) using the agar dilution method. Results: In both tests the plant extracts displayed significant in vitro inhibitory activity against the clinical and reference strains of C. perfringens assayed. Conclusion: The study is the first demonstration of the inhibitory effect of P. cordata on C. perfringens, due to its antimicrobial properties, which serves as evidence supporting its folk use. The extracts could be used as coadjuvants in the treatment of gangrenous mastitis(AU)

Introducción: la mastitis gangrenosa es una presentación clínica especial de mastitis en el ganado y pequeños rumiantes. Persea cordata Mez. , es un árbol conocido en la etnoveterinaria brasileña, cuya corteza se utiliza en la curación de heridas en animales de granja. Objetivos: investigar el efecto antimicrobiano in vitro de fracciones apolares de la corteza de P. cordata contra una cepa salvaje de C. perfringens, aislada de la ubre de una vaca con mastitis gangrenosa y una cepa de referencia. Métodos: Se recogió una muestra de leche de la ubre, se diluyeron alícuotas, y se realizaron frotis teñidos por Gram. Las alícuotas fueron inoculadas en caldo y sembradas en agar sangre, y posteriormente incubados en anaerobiosis a 37 oC/24h. La identificación bioquímica fue realizada a partir del aislamiento bacteriano. La actividad inhibitoria in vitro de las fracciones apolares de P. cordata fue evaluada utilizando la técnica de difusión en agar y la CMI (concentración minima inhibitoria) mediante el método de dilución en agar. Resultados: los extractos de la planta, en ambas pruebas, presentaron significativa actividad inhibitoria in vitro contra las cepas clínica y de referencia de C. perfringens ensayadas. Conclusión: se concluyó que, por primera vez, se demuestra un efecto inhibitorio de P. cordata sobre C. perfringens, reforzando el uso popular, debido a sus propiedades antimicrobianas. Los extractos podrán ser utilizados como coadyuvantes en el tratamiento de la mastitis gangrenosa(AU)

Antimicrobial activities of six essential oils commonly used as condiments in Brazil against Clostridium perfringens

Abstract Despite recent advances in food production technology, food-borne diseases (FBD) remain a challenging public health concern. In several countries, including Brazil, Clostridium perfringens is among the five main causative agents of food-borne diseases. The present study determines antimicrobial activities of essential oils of six condiments commonly used in Brazil, viz., Ocimum basilicum L. (basil), Rosmarinus officinalis L. (rosemary), Origanum majorana L. (marjoram), Mentha × piperita L. var. Piperita (peppermint), Thymus vulgaris L. (thyme) and Pimpinella anisum L. (anise) against C. perfringens strain A. Chemical compositions of the oils were determined by GC–MS (gas chromatography–mass spectrometry). The identities of the isolated compounds were established from the respective Kováts indices, and a comparison of mass spectral data was made with those reported earlier. The antibacterial activity was assessed from minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) using the microdilution method. Minimum inhibitory concentration values were 1.25 mg mL-1 for thyme, 5.0 mg mL-1 for basil and marjoram, and 10 mg mL-1 for rosemary, peppermint and anise. All oils showed bactericidal activity at their minimum inhibitory concentration, except anise oil, which was only bacteriostatic. The use of essential oils from these common spices might serve as an alternative to the use of chemical preservatives in the control and inactivation of pathogens in commercially produced food systems.