Behavioral and biochemical consequences after chronic exposition to the herbicide atrazine in tadpoles.

Atrazine (ATZ) is the third most sold herbicide in Brazil, occupying the seventh position between most widely used pesticides. Due to its easy outflow, low reactivity and solubility, moderate adsorption to organic matter and clay, and long soil persistence, residual herbicide can be identified after long periods following application, and its usage has been prohibited in diverse countries. Amphibians are important bioindicators to assess impact of pesticide like atrazine, due to having a partial aquatic life cycle. This study had as objective to assess the response of bullfrog (Lithobates catesbeianus) tadpoles when exposed to this herbicide. Animals were exposed for a total of 168h to following concentrations: negative control, 40 µg/L, 200 µg/L, 2000 µg/L, 20000 µg/L of ATZ. Analysis of swimming activity was performed, and biochemical profile was assessed by analysis of blood and plasma glucose levels, urea, creatinine, cholesterol, HDL, triglycerides, glutamic pyruvic transaminase (GPT), alkaline phosphatase (AP), calcium, total proteins, phenol, peroxidase and polyphenol oxidase activity. Results exhibited malnutrition, anemia, likely muscle mass loss, and hepatic damage, indicating that ATZ can lead to an increase in energy to maintain homeostasis for animal survival.

Aqueous extract from urucum (Bixa orellana L.): antimicrobial, antioxidant, and healing activity.

Background: Annatto was obtained from seed B orellana (urucum) and is commonly used in food and cosmetic industries. The objective of this study was to identify the antimicrobial and antioxidant activity of the aqueous extract from urucum seeds and its skin healing potential in exposed cutaneous lesions in rats treated with the gel containing the extract. Methods: Three types of extracts from seeds were made using chloroform, sodium hydroxide, water, and estimated bixin and norbixin. In the presence of antioxidants, antibacterial was observed and then evaluated the skin healing in rats using aqueous extract. Results: Annatto dyes have been evaluated in all three extracts. When the seeds were extracted with chloroform, bixin was detected. If extraction was performed by sodium hydroxide or water, norbixin was detected. For healing use, 10% of aqueous extract was mixed in a gel base. The finding obtained from the antioxidant assay revealed that the activities of the water extract could be used as a source of polyphenolic compounds. In chloroform extract, the antioxidant was not effective because it has weak radical scavengers. With respect to antimicrobial activity, it has been observed that aqueous extract has more effect. For skin healing assay, a total of 3 study groups were tested: negative control group (gel base), positive control group (fibrinase), and test group (gel with urucum aqueous extract). After 7 days of treatment, animals treated with fibrinase had an improvement of 4.7% in total wound area when compared with the negative control while those treated with urucum aqueous extract presented an improvement of 51.55% in comparison. After 14 days, the total wound area of animals within the test group had a decrease of 94.97% when compared with the negative control (gel base) results while the control group presented an improvement of 56.58% in total wound area. These results indicate that wounds treated with urucum aqueous extract were 38.39% more efficient than fibrinase, a cream used for skin healing. Conclusions: It is possible to conclude that gel with aqueous extract is effective in skin healing in rats, being used as a phytotherapic, besides possessing antioxidant and antimicrobial activity.

Atrazine contaminated sites and bullfrog tadpoles: evasive trends and biochemical consequences.

Atrazine (ATZ) is one of the most used active principles in agricultural systems. This pesticide has the ability to easily accumulate in terrestrial and aquatic environments, causing impacts with chronic adverse effects. Avoidance tests are tests that seek to assess the concentration from which a given organism escapes, that is, migrates to another habitat. They are being used as a modality of innovative and minimally invasive ecotoxicological tests. Our objective was to evaluate the sensitivity and possible toxic effects of ATZ in bullfrog tadpoles (Lithobates catesbeianus), through avoidance tests and oxidative stress analyses. We performed the behavioral avoidance test lasting 12 h, with observations every 60 min in a linear multi-compartment system with seven compartments. Each compartment corresponded to a concentration: negative control, 1, 2, 20, 200, 2000, 20,000 µg L-1. After the selection of habitat, organisms were forcedly maintained in the chosen concentrations for 48 h and then, metabolic effects were measured assessing the blood plasma amino acid profile and liver protein degradation. We also determined the effective concentrations of ATZ tested at 0 h and 48 h. The results showed that there was an effect of the treatment on the distribution of tadpoles, but not on the hours or on the combined effect (interaction). The biochemical analyses also showed a concentration-dependent relationship which caused significant toxic effects even in a short period of time. In conclusion, these frogs were able to avoid places with high concentrations of ATZ in the first hours of exposure, which suggests that in the natural environment these animals can migrate or avoid areas contaminated by this herbicide; however, depending on the selected concentration, serious biochemical consequences can occur.

Histological and biochemical effects of preventive and therapeutic vascular photobiomodulation on rat muscle injury.

The intravascular or transcutaneous application of photobiomodulation (PBM) over blood vessels (vascular photobiomodulation, VPBM) has been used for the treatment of inflammatory and chronic conditions with promising systemic results. This study evaluated the VPBM effects on a model of muscle regeneration after acute injury and compared the outcomes of preventive and therapeutic VPBM. Transcutaneous VPBM was administered over the rat's main tail vein. Serum levels of creatine kinase (CK), aspartate aminotransferase (AST), and lactate were evaluated and muscles were processed for macroscopic and microscopic analysis. Preventive and therapeutic VPBM led to decreased inflammatory infiltrate, edema, and myonecrosis but with an increase in immature muscle fibers. CK, AST, and lactate levels were lower in the groups treated with VPBM (lowest concentrations in preventive VPBM application). Preventive and therapeutic VPBM were capable of exerting a positive effect on acute muscle injury repair, with more accentuated results when preventive VPBM was administered.

Hypoglicemic and Hypolipedimic Effects of Ganoderma lucidum in Streptozotocin-Induced Diabetic Rats.

Background:Ganoderma lucidum (Leyss. Ex. Fr) Karst is a basidiomycete mushroom that has been used for many years as a food supplement and medicine. In Brazil, National Health Surveillance Agency (ANVISA) classified Ganoderma lucidum as a nutraceutical product. The objective of the present work was to observe the effects of an extract from Ganoderma lucidum in rats treated with streptozotocin, and an agent that induces diabetes. Method: Male Wistar rats were obtained from the animal lodging facilities of both University Nove de Julho (UNINOVE) and Lusiada Universitary Center (UNILUS) with approval from the Ethics Committee for Animal Research. Animals were separated into groups: (1) C: Normoglycemic control water; (2) CE: Normoglycemic control group that received hydroethanolic extract (GWA); (3) DM1 + GWA: Diabetic group that received extract GWA; and (4) DM1: Diabetic group that received water. The treatment was evaluated over a 30-day period. Food and water were weighted, and blood plasma biochemical analysis performed. Results: G. lucidum extract contained beta-glucan, proteins and phenols. Biochemical analysis indicated a decrease of plasma glycemic and lipid levels in DM rats induced with streptozotocin and treated with GWA extract. Histopathological analysis from pancreas of GWA-treated DM animals showed preservation of up to 50% of pancreatic islet total area when compared to the DM control group. In plasma, Kyn was present in diabetic rats, while in treated diabetic rats more Trp was detected. Conclusion: Evaluation from G. lucidum extract in STZ-hyperglycemic rats indicated that the extract possesses hypoglycemic and hypolipidemic activities. Support: Proj. CNPq 474681/201.

Indoleamine 2, 3-dioxygenase (IDO) increases during renal fibrogenesis and its inhibition potentiates TGF-ß 1-induced epithelial to mesenchymal transition.

BACKGROUND: Indoleamine 2, 3-dioxygenase (IDO) is an immunomodulatory molecule that has been implicated in several biological processes. Although IDO has been linked with some renal diseases, its role in renal fibrosis is still unclear. Because IDO may be modulated by TGF-ß1, a potent fibrogenic molecule, we hypothesized that IDO could be involved in renal fibrosis, especially acting in the TGF-ß1-induced tubular epithelial-mesenchymal transition (EMT). We analyzed the IDO expression and activity in a model of renal fibrogenesis, and the effect of the IDO inhibitor 1-methyl-tryptophan (MT) on TGF-ß1-induced EMT using tubular cell culture. METHODS: Male Wistar rats where submited to 7 days of UUO. Non-obstructed kidneys (CL) and kidneys from SHAM rats were used as controls. Masson's Tricrome and macrophages counting were used to chatacterize the tissue fibrosis. The EMT was analysed though immunohistochemistry and qRT-PCR. Immunohistochemestry in tissue has used to show IDO expression. MDCK cells were incubated with TGF- ß1 to analyse IDO expression. Additionally, effects of TGF- ß1 and the inhibition of IDO over the EMT process was acessed by immunoessays and scrath wound essay. RESULTS: IDO was markedly expressed in cortical and medular tubules of the UUO kidneys. Similarly to the immunolocalizaton of TGF- ß1, accompanied by loss of e-cadherin expression and an increase of mesenchymal markers. Results in vitro with MDCK cells, showed that IDO was increased after stimulus with TGF-ß1, and treatment with MT potentiated its expression. MDCK stimulated with TGF-ß1 had higher migratory activity (scratch-wound assay), which was exacerbated by MT treatment. CONCLUSIONS: IDO is constitutively expressed in tubular cells and increases during renal fibrogenesis. Although IDO is induced by TGF-ß1 in tubular cells, its chemical inhibitor acts as a profibrotic agent.

Effects of Dietary Supplementation with Agaricus sylvaticus Schaeffer on Glycemia and Cholesterol after Streptozotocin-Induced Diabetes in Rats.

This study evaluated the effect of the Agaricus sylvaticus (sun mushroom) on biochemical tests of the plasma and on the morphology of the pancreas in an experimental model of type I diabetes mellitus (DM1) induced by streptozotocin. One gram of dry A. sylvaticus was homogenized and mixed with the chow. Male Wistar rats were allocated as follows: normoglycemic control that received commercial chow; normoglycemic control group that received chow with A. sylvaticus; diabetic group that received commercial chow; and diabetic group that received chow with A. sylvaticus. Weight, food, and water consumption were measured every two days. Blood glucose levels were measured twice a week. After 30 days, the animals were euthanized and blood was collected for the analysis of cholesterol, HDL, triglycerides, blood sugar, glutamic-pyruvic transaminase (GPT), alkaline phosphatase, iron, transferrin, and urea. The pancreas was processed for microscopic analysis. A. sylvaticus modulated the levels of cholesterol, HDL, triglycerides, blood sugar, GPT, alkaline phosphatase, iron, transferrin, and urea to levels similar to those found in the controls and led to compensatory hyperplasia of the islets of Langerhans. A. sylvaticus is potentially beneficial in the control of type 1 diabetes, and it may also prevent pancreas damage.

Análise preliminar do tratamento de Diabetes mellitus com Polissacarídeo de Tremella fuciformis / Preliminary analysis of the treatment of Diabetes mellitus with Tremella fuciformis polysaccharide

Introdução: O Diabetes mellitus é uma desordem metabólica que ocorre no mundo inteiro, caracterizada por hiperglicemia associada a problemas com secreção ou ação da insulina ou, ainda por alterações no metabolismo intermediário de carboidratos, proteína e lipídeos. O cogumelo Tremella fuciformis (Basideomycota) foi isolado no Brasil e levado para a China onde tem sido produzido e utilizado como alimento por apresentar diversas atividades biológicas como anti-inflamatório, anti-mutagênico, reduz hipertensão, reduz diabetes entre outras propriedades relacionadas com imunidade. A Embrapa de Brasília tornou isolar o cogumelo e enviou a universidade para os testes preliminares. Objetivo: O presente trabalho teve como objetivo induzir a diabetes em ratos e realizar tratamento com polissacarídeo (PS) extraído do cogumelo gelatinoso Tremella fuciformis, desenvolvido em frascos no laboratório. Método: Ratos, no total de 28 animais foram divididos em 4 grupos sendo: 1-Normal) grupo recebendo dieta normal e água; 2-Sacarose) grupo recebendo ração normal e uma solução de sacarose 20% por 65 dias; 3-Sacarose + PS) grupo recebendo ração normal + solução de sacarose (65dias) e por gavagem PS na concentração de 1mmol (nos últimos 20 dias sendo uma vez/semana) ; 4-idem ao grupo 3, entretanto PS com concentração de 2mmol. No período, os ratos (uma vez/semana) foram pesados e submetidos a teste de glicose (fita Accu Check) e, depois sacrificados com dose letal de analgésico e coleta do sangue para testes de glicose, colesterol, triglicérides, creatinina e HDL. Resultados: Os resultados parciais demonstraram que os animais submetidos à dieta com sacarose aumentaram o peso e glicemia. Já os animais submetidos a tratamento com o PS permaneceram com o peso praticamente constante e, redução da glicemia. A creatinina tem sido um parâmetro para diagnosticar problemas renais, mas os animais em todos os tratamentos, não apresentaram diferença estatística. Para colesterol os animais submetidos ao tratamento com o PS apresentaram valores abaixo dos encontrados no grupo com sacarose, entretanto, com triglicérides e HDL apresentaram diminuição, mas houve, aumento em relação aos animais do grupo normal, indicando controle nos lipídeos. Por conclusão os resultados preliminares demonstraram que o PS extraído do cogumelo Tremella fuciformis apresenta grande potencial como produto natural contra diabetes.

Healing and cytotoxic effects of psidium guajava (Myrtaceae) leaf extracts

Aim: The aims of this study were to evaluate the wound healing potential in vivo and the cytotoxic effects in vitro of Psidium guajava (Myrtaceae) leaf extract and commonly used corticosteroids. Methods: The healing effect was studied in vivo by the clinical and histological evaluation of traumatic lesions in the oral mucosa of rats treated with these substances. Each rat received 2 daily applications of the medicine tested and the animals were sacrificed after 1, 3, 5, 7 and 14 days. Tissue sections stained with hematoxylin & eosin were analyzed. The histological evaluation involved a 5-point scoring system based on the degree of healing, ranging from 1 (total repair of epithelium and connective tissue) to 5 (epithelial ulcer and acute inflammatory infiltrate). The Kruskal-Wallis test was used for statistical analysis of the histological scores. For the in vitro toxicity assay, each substance was applied to mucosa fibroblast cell cultures in conditioned media. The media were conditioned by placing the substances in contact with fresh culture medium for 24 h. The cytotoxicity analysis was performed using the MTT assay. Data were analyzed statistically by ANOVA and Tukey’s test at 5% significance level. Results: In vitro, the guava extract caused a decrease in the cell viability and growth when compared to the control and corticosteroids. In vivo, guava extract caused accelerated wound healing from the 3rd day, whereas the corticosteroids delayed tissue repair and were associated with bacterial surface colonization, the presence of micro-abscesses and intense inflammatory infiltrate in the submucosa. Conclusions: Although in a short-term cytotoxicity analysis, the guava extract reduced the cell population in vitro, while in vivo, the extract accelerated wound healing.

Pectin methylesterase activity and ascorbic acid content from guava fruit, cv. Predilecta, in different phases of development.

The guava pectin methylesterase (PME) specific activity and vitamin C were assayed in samples from different phases of guava fruit development. The PME enzyme from guava was extracted with borate-acetate buffer, 50 mol/l, pH 8.0, in the presence of NaCl 0.3 mol/l. The results showed PME optimum activity at pH 9 and 95 degrees C, and it is a thermostable enzyme. Guava PME retained 96.8% of activity after 300 min in 90 degrees C. Electrophoresis showed that guava PME contained two isoforms, one with 57 kDa molecular mass. The analyses of the different phases of guava maturation showed that ascorbic acid decreases during the maturation process, but PME activity increases with maturation.

Efeito de cogumelos medicinais na reabilitação da inflamação químio-induzida / Effect of medicinal mushrooms on rehabilitation of chemotherapy induced inflammation

Introdução: A inflamação químio-induzida é uma complicação dose limitante comum no tratamento citorredutor do câncer. Caracteriza-se por inflamação e ulceração da mucosa oral cuja severidade pode levar a alteração ou até interrupção do tratamento oncológico. Objetivo: comparar, por meio de análises clínicas e histopatológicas, a ação do Cogumelo do Sol® no processo inflamatório e reparador da mucosite quimionduzida. Métodos: Foram utilizados 30 Golden hamsters que receberam injeção intraperitoneal de quimioterápico 5-FU nos dias 0 e 2 do experimento. Nos dias 3 e 4, a mucosa jugal direita foi arranhada com a ponta de uma agulha estéril. A partir do 5º dia, foi iniciada a terapêutica com o fitoterápico. Nos dia 0, 2, 5, 10 e 12 foi feita avaliação clínica e três animais foram sacrificados e a mucosa jugal removida para análise histopatológica. Os dados obtidos foram submetidos à análise estatística pelo teste ANOVA complementado por Tukey. Resultados: após o quinto dia, houve o desenvolvimento de inflamação com o 5-FU e a maior severidade foi observada no décimo dia. Não houve redução clínica e histopatológica significativa do grau de inflamação com o tratamento tópico empregado. Conclusão: o extrato de cogumelo utilizado não foi efetivo na reabilitação da inflamação químio-induzida em hamsters.

Introduction: the chemotherapy induced inflammation is considered a significant complication of cancer treatment. This condition is characterized by inflammation and ulceration of the oral mucosa that can directly affect the clinical status of the patient and interfere with the patient oncological treatment. Objective: to compare the effect of medicinal mushrooms on the rehabilitation of chemoinduzed inflammation by clinical and histophatological evaluation. Methods: the inflammation was induced in 30 male Golden hamsters by two intraperitoneal administrations of 5-FU on the 0 and 2nd days of the experiment followed by mechanical trauma of the cheek pouch on the third and fourth day. Animals received the topical medicinal mushrooms daily since the 5th day until the end of the experiment on the 12th day. Macroscopic and histopathological analyses were evaluated and graded. The data were compared by Anova (p < 0.05) with Tukey's post hoc test. Results: after the 5th day the inflammation was observed and the most severe aspect was note after 10 days. The topical treatment with medicinal mushrooms do not improved clinically or histopathologically the recovery from 5-fluorouracil-induced damage. Conclusion: the medicinal mushrooms extract was not effective on the rehabilitation of chemotherapy induced inflammation.

Identification of Bipolaris bicolor and Bipolaris sorokiniana on wheat seeds (Triticum aestivum L) in Brazil

Diseases caused in wheat by Helminthosporium spp. have led to considerable yield and production losses. Different species in this genus are associated with wheat seeds. In Brazil, spot blotch in wheat is caused by Bipolaris sorokiniana (Sacc) Schoem, and another fungus Bipolaris bicolor (Mitra) Shoem that has been also isolated from wheat seeds. The current study was undertaken to identify the most frequent fungus species that normaly infects wheat seeds and compared them with B. sorokiniana. The fungus Bipolaris bicolor (Mitra) Shoem., isolated from wheat seeds cultivar IAPAR, was identified by taxonomic methods and compared with the fungus Bipolaris sorokiniana (Sacc.) Shoem., in relation to growth characteristics on the seeds, as well as to growth characteristics in PDA and morphology of the structures. Type of colony observed on the seeds is important for the differentiation between the fungus species. Bipolaris sorokiniana presented black colonies, which were well-adherent to the seeds, whereas B. bicolor presented grayish, aerial, cotton-like colonies. The size of the conidia also differed in length and width, and B. bicolor presented the smallest dimensions. In relation to septa, B. bicolor conidia presented deep ones, with dark color bases, but seldom presented dark apex. Bipolaris sorokiniana presented homogenous color.

Doenças causadas por Helminthosporium spp. em trigo, causam consideráveis perdas na produção. Diferentes espécies do gênero do fungo podem ser encontradas em sementes. No caso do Brasil, a mancha foliar do trigo tem sido causada por Bipolaris sorokiniana (Sacc) Schoem, entretanto, outro fungo como Bipolaris bicolor (Mitra) Shoem tem sido isolado de sementes do trigo. O objetivo do presente trabalho foi identificar as espécies de fungo que normalmente infectam sementes de trigo e comparar com a mais comum B. sorokiniana. O fungo Bipolaris bicolor (Mitra) Shoem., isolado de sementes de trigo var. IAPAR, foi identificado por métodos taxonômicos e comparado com o fungo Bipolaris sorokiniana (Sacc.) Shoem. em relação ao crescimento sobre as sementes bem como às características culturais no meio BDA e morfologia das estruturas. O tipo de colônia observada sobre as sementes é importante para diferenciar as espécies entre si. O fungo B. sorokiniana apresentou colônias de cor preta sendo bem aderidas às sementes, enquanto B. bicolor apresentou colônias aéreas acinzentadas e com aspecto cotonoso. O tamanho dos conídios também diferenciaram no comprimento e largura onde os valores menores corresponderam a B. bicolor. Em relação aos septos, os conídios de B. bicolor apresentavam septo "profundo", com coloração escura na base e, raras vezes no ápice. Os conídios de B. sorokiniana apresentaram coloração homogênea.

Identification of Bipolaris bicolor and Bipolaris sorokiniana on wheat seeds (Triticum aestivum L) in Brazil

Diseases caused in wheat by Helminthosporium spp. have led to considerable yield and production losses. Different species in this genus are associated with wheat seeds. In Brazil, spot blotch in wheat is caused by Bipolaris sorokiniana (Sacc) Schoem, and another fungus Bipolaris bicolor (Mitra) Shoem that has been also isolated from wheat seeds. The current study was undertaken to identify the most frequent fungus species that normaly infects wheat seeds and compared them with B. sorokiniana. The fungus Bipolaris bicolor (Mitra) Shoem., isolated from wheat seeds cultivar IAPAR, was identified by taxonomic methods and compared with the fungus Bipolaris sorokiniana (Sacc.) Shoem., in relation to growth characteristics on the seeds, as well as to growth characteristics in PDA and morphology of the structures. Type of colony observed on the seeds is important for the differentiation between the fungus species. Bipolaris sorokiniana presented black colonies, which were well-adherent to the seeds, whereas B. bicolor presented grayish, aerial, cotton-like colonies. The size of the conidia also differed in length and width, and B. bicolor presented the smallest dimensions. In relation to septa, B. bicolor conidia presented deep ones, with dark color bases, but seldom presented dark apex. Bipolaris sorokiniana presented homogenous color(AU)

Doenças causadas por Helminthosporium spp. em trigo, causam consideráveis perdas na produção. Diferentes espécies do gênero do fungo podem ser encontradas em sementes. No caso do Brasil, a mancha foliar do trigo tem sido causada por Bipolaris sorokiniana (Sacc) Schoem, entretanto, outro fungo como Bipolaris bicolor (Mitra) Shoem tem sido isolado de sementes do trigo. O objetivo do presente trabalho foi identificar as espécies de fungo que normalmente infectam sementes de trigo e comparar com a mais comum B. sorokiniana. O fungo Bipolaris bicolor (Mitra) Shoem., isolado de sementes de trigo var. IAPAR, foi identificado por métodos taxonômicos e comparado com o fungo Bipolaris sorokiniana (Sacc.) Shoem. em relação ao crescimento sobre as sementes bem como às características culturais no meio BDA e morfologia das estruturas. O tipo de colônia observada sobre as sementes é importante para diferenciar as espécies entre si. O fungo B. sorokiniana apresentou colônias de cor preta sendo bem aderidas às sementes, enquanto B. bicolor apresentou colônias aéreas acinzentadas e com aspecto cotonoso. O tamanho dos conídios também diferenciaram no comprimento e largura onde os valores menores corresponderam a B. bicolor. Em relação aos septos, os conídios de B. bicolor apresentavam septo profundo, com coloração escura na base e, raras vezes no ápice. Os conídios de B. sorokiniana apresentaram coloração homogênea(AU)

Increased production of beta-1,3 glucanase and proteins in Bipolaris sorokiniana pathosystem treated using commercial xanthan gum.

Barley plants (cultivars Embrapa 127, 128 and 129) treated with xanthan gum, and with different time intervals between the administration of the inducer and the pathogen. demonstrated induction of resistance against Bipolaris sorokiniana. Induction was shown to have local and systemic action. In order to prove the resistance effect, biochemical analyses were performed to quantify proteins and the enzymatic activity of beta-1,3 glucanase. Results demonstrated that barley plants treated with the inducer, showed an increase in the concentration of proteins, as well as in the activity of the enzyme beta-1,3 glucanase, when compared with the extract from healthy plants. In infected plants, protein concentrations decreased and enzymatic activity was lower than in healthy plants. Results suggest that barley plants treated with xanthan gum developed mechanisms responsible for induced resistance, which are still unknown. The most important macromolecule in the defense mechanism was demonstrated to be PR-protein, due to its accumulation and concentration of proteins. However, it may not be the only macromolecule responsible for the resistance effect.

Comparison of electrophoretic protein profiles of campylobacter jejuni subsp. jejuni isolated from different animal species

Electrophoretic protein profiles of Campylobacter jejuni subsp. jejuni strains isolated from feces of seven animal species, including man, were compared. Fourteen strains (two from each species) plus two human strains and the reference one, were ruptured by ultrasound and their total soluble proteins were analyzed by SDS-PAGE technique in a 12(per cent) polyacrylamide gel with computerized densitometric reading by the molecular analyst software. All the strains had bands in common that correspond to 45 and 66 Kda molecular weight. The disagreement corresponded to a 97 to 200 Kda molecular weight region. From the 17 strains, 13 (76.5 per cent), were classified as biotype I, three (17.6 per cent) as biotype II and one (5.8 per cent) as biotype III. Since protein extracts were obtained from cells grown under identical conditions, and thus, able to express the same phenotype, this disagreement region could be related to different genotypes or serotypes.