Rita de Cássia Trindade

Yeasts associated with fresh and frozen pulps of Brazilian tropical fruits.

The occurrence of yeasts on ripe fruits and frozen pulps of pitanga (Eugenia uniflora L), mangaba (Hancornia speciosa Gom.), umbu (Spondias tuberosa Avr. Cam.), and acerola (Malpighia glaba L) was verified. The incidence of proteolytic, pectinolytic, and mycocinogenic yeasts on these communities was also determined. A total of 480 colonies was isolated and grouped in 405 different strains. These corresponded to 42 ascomycetous and 28 basidiomycetous species. Candida sorbosivorans, Pseudozyma antarctica, C. spandovensis-like, C. spandovensis, Kloeckera apis, C. parapsilosis, Rhodotorula graminis, Kluyveromyces marxianus, Cryptococcus laurentii, Metchnikowia sp (isolated only from pitanga ripe fruits), Issatchenkia occidentalis and C. krusei (isolated only from mangaba frozen pulps), were the most frequent species. The yeast communities from pitanga ripe fruits exhibited the highest frequency of species, followed by communities from acerola ripe fruits and mangaba frozen pulps. Yeast communities from frozen pulp and ripe fruits of umbu had the lowest number of species. Except the yeasts from pitanga, yeast communities from frozen pulp exhibited higher number of yeasts than ripe fruit communities. Mycocinogenic yeasts were found in all of the substrates studied except in communities from umbu ripe fruits and pitanga frozen pulps. Most of the yeasts found to produce mycocins were basidiomycetes and included P. antarctica, Cryptococcus albidus, C. bhutanensis-like, R. graminis and R. mucilaginosa-like from pitanga ripe fruits as well as black yeasts from pitanga and acerola ripe fruits. The umbu frozen pulps community had the highest frequency of proteolytic species. Yeasts able to hydrolyse casein at pH 5.0 represented 38.5% of the species isolated. Thirty-seven percent of yeast isolates were able to hydrolyse casein at pH 7.0. Pectinolytic yeasts were found in all of the communities studied, excepted for those of umbu frozen pulps. The highest frequency of pectinolytic activity was found in mangaba frozen pulp communities. Around 30% of all isolates produced pectinases. The ability to split arbutin was observed in all communities ranging from 8% in yeasts from pitanga frozen pulps to 40.6% in acerola ripe fruit communities. Among 432 species tested, 125 were active for beta-glucosidase production, and Kloeckera apis, P. antarctica, C. sorbosivorans, and C. spandovensis-like were the most active species.

Spoligotypes of Mycobacterium tuberculosis complex isolates from patients residents of 11 states of Brazil

One of the high tuberculosis (TB) incidence countries in the world, Brazil is characterized by considerable differences in TB incidence on regional and state level. In the present study, we describe Brazilian spoligotypes of 1991 Mycobacterium tuberculosis complex (MTC) clinical isolates from patients residents of 11 states from different regions of the country, diagnosed between 1996 and 2005. By performing spoligotyping on a large number of M. tuberculosis clinical isolates, one of the main objectives of this study was to determine the major genotype families causing TB in Brazil and to verify the region-associated genotype distribution. We observed a total of 577 distinct spoligopatterns, 12.6% of these corresponded to orphan patterns while 87.4% belonged to 326 shared-types (SITs). Among the latter, 86 SITs (isolated from 178 patients) had been observed for the first time in this study, the most frequent being SIT2517 which belonged to the T3-ETH lineage and was exclusively found among patients residents of Belém, the capital of the state of Pará (n=8 isolates). Irrespective of shared-type labeling, a total of 19.5% strains were unique (unclustered) in our study as opposed to 80.5% clustered isolates (189 clusters, size range from 2 to 205 isolates). The three largest clusters were SIT42 of the Latin-America & Mediterranean (LAM) 9 clade (10.3%), SIT53 of the T clade (7.6%), and SIT50 of the Haarlem clade (5.4%). The predominant MTC lineages in Brazil in decreasing order belonged to the LAM (46%); the ill-defined T (18.6%); the Haarlem (12.2%), the X (4.7%), the S (1.9%), and the East African Indian (EAI) (0.85%) families. The rest of clades grouped together as Mycobacterium africanum, Mycobacterium bovis, Beijing, Central Asian (CAS), and the Manu types, represented less than 1% of the strains. Finally, about 15% of the isolates showed spoligotype signatures that were not yet classified among well-defined lineages. In conclusion, we provide hereby a first insight into the population structure of MTC isolates in Brazil, showing the predominance of both LAM and T family and the existence of region-associated genotypes.

Chemical composition and antimicrobial activity of the essential oil of Hyptis pectinata (l.) Poit.

Essential oil was extracted from leaves of Hyptis pectinata using hydrodistillation, and its composition determined using GC-FID and GC-MS. Chemical analysis showed that there was a predominance of sesquiterpenes, of which β-caryophyllene (18.34%), caryophyllene oxide (18.00%) and calamusenone (24.68%) were measured for the first time in the genus Hyptis. Twenty-one compounds were identified, and calamusenone was isolated using preparative thin layer chromatography with a silica gel plate (60 PF254). The minimal inhibitory concentration (MIC) and minimal microbicidal concentration (MMC) were determined for various pathogenic microorganisms. H. pectinata oil was most effective against Gram (+) bacteria and yeasts.

Conjunctival microbial flora of clinically normal persons who work in a hospital environment

The objective of the work was to study the microbiota of the conjunctival secretion of health professionals. Samples were collected from the clinically normal eyes of 40 health professionals in four different sectors, Proctology, General Intensive Care Unit (ICU), Male Ward, and Oncology of Hospital das Clinicas Dr. Augusto Leite, Aracaju, SE, Brazil. Ten professionals from each sector were selected. The samples were inoculated into various culture media: blood agar, Chapman agar, EMB medium (Teague), and Sabouraud dextrose agar with chloramphenicol. The bacteria most frequently isolated from all the sectors were Staphylococcus epidermidis (45.0%) and Bacillus sp (29.0%). The least frequent bacteria were Proteus sp (6.1%), Staphylococcus aureus (4.1%), Enterobacter sp (4.1%), Alcaligenes sp (4.1%), Citrobacter sp (2.1%), Moraxella sp (2.1%), and Proteus mirabilis (2.1%). Fungi were not isolated. These results confirm the continuous contamination of the conjunctival sac of these professionals by the external environment, while at the same time confirming that the mechanisms of local defence continue to be intact, preventing the fixation of invading microorganisms.

Saccharomyces cerevisiae and non-Saccharomyces yeasts in grape varieties of the São Francisco Valley

The aims of this work was to characterise indigenous Saccharomyces cerevisiae strains in the naturally fermented juice of grape varieties Cabernet Sauvignon, Grenache, Tempranillo, Sauvignon Blanc and Verdejo used in the São Francisco River Valley, northeastern Brazil. In this study, 155 S. cerevisiae and 60 non-Saccharomyces yeasts were isolated and identified using physiological tests and sequencing of the D1/D2 domains of the large subunit of the rRNA gene. Among the non-Saccharomyces species, Rhodotorula mucilaginosa was the most common species, followed by Pichia kudriavzevii, Candida parapsilosis, Meyerozyma guilliermondii, Wickerhamomyces anomalus, Kloeckera apis, P. manshurica, C. orthopsilosis and C. zemplinina. The population counts of these yeasts ranged among 1.0 to 19 × 105 cfu/mL. A total of 155 isolates of S. cerevisiae were compared by mitochondrial DNA restriction analysis, and five molecular mitochondrial DNA restriction profiles were detected. Indigenous strains of S. cerevisiae isolated from grapes of the São Francisco Valley can be further tested as potential starters for wine production.

Multilocus enzyme electrophoresis analysis and exoenzymatic activity of Candida albicans strains isolated from women with vaginal candidiasis.

Twenty‐eight Candida albicans strains obtained from women with vaginal candidiasis were tested for phospholipase and proteinase production and clustered by multilocus enzyme electrophoresis (MLEE). The proteolytic and phospholipidic activity were considered moderate (0.56 ± 0.12 mm and 0.53 ± 0.09 mm, respectively) for all isolates. The isoenzymes malate dehydrogenase (MDH) and sorbitol dehydrogenase (SDH) showed strong intra‐specific discriminatory power. The numerical and genetic interpretation of the bands produced by the isoenzymes tested presented similar discriminatory power. The genetic diversity of the isolates was measured by allelic and genic frequency, perceptual index of polymorphic loci (P = 87.5%), average number of alleles per locus, average number of alleles per polymorphic locus, average heterozygosity observed and average heterozygosity expected. We verified that three isoenzymatic loci (Adh, Gdh and Sdh‐2) were not in Hardy–Weinberg equilibrium. A dendrogram constructed based on the genetic distance matrix of Nei showed seven clusters; 57.15% (16) of the isolates were considered highly related or indistinguishable, and 42.85% were considered moderately related or unrelated. We did not find a relationship between the clusters and the exoenzymes production.

Biological activity of Cryptococcus neoformans and Cryptococcus gattii from clinical and environmental isolates

INTRODUCTION: Cryptococcus neoformans and Cryptococcus gattii are encapsulated basidiomycetous yeasts with worldwide distribution. They cause cryptococcosis with features of systemic infection, affecting the central nervous system, lungs and skin in humans and animals. These fungi present numerous virulence factors that allow them to invade the host and multiply, among which extracellular enzyme capacity and microbial adaptation to different temperatures are worth mentioning. OBJECTIVE: To evaluate the production of protease and investigate possible differences in thermotolerance and urease activity in clinical and environmental yeast isolates. MATERIAL AND METHODS: Culture methods and Pz analysis were applied to assess urease and protease, whereas the optical density method was used to analyze biological activity in thermotolerance. RESULTS: There was no significant results as to microbial growth at the tested temperatures (25o, 37o and 42oC). It was observed that clinical specimens grew better than environmental ones at elevated temperatures. As to C. neoformans, the moderate production of urease enzyme prevailed in both clinical and environmental isolates within 24h or 48h. Moreover, there was significant production on the seventh day of reading. The best reading time for viewing protease production in both isolates and species was the seventh day: 96% clinical samples and 94% environmental isolates. CONCLUSION: Further studies are required in order to investigate the virulence factors of C. neoformans and C. gattii cerebrospinal isolates from patients with meningoencephalitis and environmental samples from Sergipe. Furthermore, a higher technical accuracy and statistical precision are indispensable.

Evaluation of the hepatotoxicity of Abarema cochliacarpos extracts in mice Mus musculus

Abarema cochliacarpos (Gomes) Barneby & J.W. Grimes, Fabaceae, is a native species of Brazil popularly known as “barbatimao”, frequently found along the north coast of the state of Bahia. Local communities make an infusion from its stem bark, which is used to treat several diseases. This study aimed to evaluate the hepatotoxicity of A. cochliacarpos extracts in mice Mus musculus. The bark infusion and hydroalcoholic extract were administered nasogastrically into two groups of eight animals (four male and four female each). After 45 days all mice were killed and the livers were collected for further histological analysis. Hepatic steatosis, congestion of the hepatic vessels and presence of macrophages and lymphocytes infi ltrates in the liver, were observed in both group of animals, additionally animals that received the stem bark infusion presented an accumulation of pigments. None of the animals belonging to the negative control group showed any of the symptoms described above. In conclusion, the hydroalcoholic extract and infusion of A. cochliacarpos stem bark were proven to cause intoxication in mice. The hepatotoxicity of the infusion was more aggressive in females. Further studies are necessary to isolate compounds responsible for the toxic characteristics of A. cochliacarpos.

Identification of yeasts Isolated from processed and frozen cocoa (Theobroma cacao) pulp for wine production

The alternative use of cocoa (Theobroma cacao) for wine production was tested. The pulp samples, obtained from Formosa farm, Itacare, Brazil, were diluted, homogenized and inoculated on Sabouraud dextrose agar medium (SDA) and incubated at 28o C for 5-8 days. Selected colonies were tested for the ability to ferment cocoa pulp and divided into fermentative, non-fermentative and weak/late fermentative species. Isolates characterized as fermentative were further tested in a small-scale wine production plant and identified. Species from the genus Brettanomyces constituted the main fermentative yeasts, with the exception of two Kloeckera apis samples. The final wine product was normally pale or clear, making clarification unnecessary, and with a sweet or dry pleasant flavor. The predominance of Brettanomyces species in cocoa pulp indicated its ecological importance in this environment and pointed to an active role of Brettanomyces in the deterioration process of the processed cocoa pulp.

Inhibition of Drug-Sensitive and Drug-Resistant Mycobacterium Tuberculosis Strains by Essential Oil from Croton Argyrophylloides Mull. Arg.

Objetcitve: To assess in vitro effects of essential oil extracted from Croton argyrophylloides against clinical and standard strains of Mycobacterium tuberculosis , comparing its resistance and sensitivity profiles to drugs commonly used in therapy. Method: In the present study, chemical composition and antimycobacterial activity of essential oils extracted from aerial parts of Croton argyrophylloides collected in Curituba district, Sergipe, Brazil were analysed. The oil was studied by GC and GC-MS and its antimicobacterial activity (MIC) was tested against 49 clinical and standard covers H 37 RV using the REMA method. To access sensitivity to isoniazid, rifampicin, ethambutol and streptomycin it was used proportions indirect test method. Results: Twenty-seven chemicals were identified, totalizing 95.98% of the composition of essential oil. The oil presented good antibacterial activity (MIC = 97 to 195 g / ml) against strains of Mycobacterium tuberculosis H37Rv and pattern one. Conclusion: On pharmacological activities of these species confirmed in vitro scientific support for its use in traditional herbal preparations.