Aim: To determine the antimicrobial susceptibility profiles of E. coli isolates of porcine origin in Grenada, West Indies.
Study Design: During the period of May to July, 2014, rectal swab samples were collected from pigs of six weeks to 12 week of age, from randomly selected small scale pig farms from the six parishes of Grenada and analyzed in the bacteriology lab in the Pathobiology Department, School of Veterinary Medicine, St. George’s University, Grenada.
Methodology: A total of 180 rectal swab samples were examined for the presence of E. coli by culture. All the isolates were tested against 12 antibiotics using the standard Kirby-Bauer disc diffusion method.
Results: All the 180 tested pigs were culture positive for E. coli. Antimicrobial susceptibility tests against 12 drugs showed susceptibility of all the E. coli isolates to amoxicillin-clavulanic acid, cefotaxime, ceftazidime, ciprofloxacin, imipenem, and gentamicin. Rate of resistance to tetracycline (96%) was the highest. Low rates of resistance to trimethoprim-sulfamethoxazole (3%), ampicillin (3%), chloramphenicol (1%), neomycin (1%) and cephalothin (1%) were observed. However, 22% of isolates showed intermediate resistance to cephalothin. Only 6% of the E. coli isolates showed resistance to two or more antibiotics.
Conclusion: This study showed that young healthy pigs in Grenada are not major reservoirs for multiple resistant E. coli. This study also confirms the inefficacy of tetracycline against E. coli of porcine origin.
Aims: To isolate and identify the endophytic Nocardiopsis sp.5 from Tulsi (Ocimum sanctum) leaves and estimates its antimicrobial activity against various human pathogens and tea pathogens.
Study Design: Rare endophytic actinobacteria isolation, identification and estimation of antimicrobial activity.
Place and Duration of Study: Department of Botany and Department of Bioinformatics, Nirmala College for Women, Coimbatore – between December 2011 and December 2012.
Methodology: Pre-sterilization of Ocimum sanctum leaves and isolation of rare endophytic actinomycetes using selective media. Estimation of antimicrobial activity of these isolates by primary and secondary streaking methods. Morphological and Molecular Identification of the most bioactive isolate.
Results: Out of 11 endophytes, four isolates (2, 3, 5, and 9) showed antagonistic activity against tea and human pathogens. Among these four isolates, isolate no.5 showed maximum activity against all the human pathogenic microorganisms such as Staphylococcus aureus (21mm), Candida albicans (18 mm), Enterococcus faecalis (19mm), Vibrio cholera (18mm) and tea pathogens such as Glomerella cingulata (14mm) Hypoxylon serpens (17mm) and Pestalopsis theae (18mm). Hence, morphological and phylogenetic studies show that isolate no.5 belongs to Nocardiopsis group, showing 99% similarity to both Nocardiopsis synnemataformans and Nocardiopsis dassonvillei.
Conclusion: Endophytic Nocardiopsis strain 5 was shown to produce good antimicrobial activity against plant pathogens and human pathogens. Further purification, structure elucidation and characterization of the antimicrobial compound from Nocardiopsis 5 strain are recommended. There is definite scope for bioprospecting of antagonistic actinomycetes from Western Ghats once appropriate consistent studies are undertaken.
Domestic pigs were inoculated with 50 (low) or 5000 (high) haemadsorbing doses (HAD50) via intranasal (IN) or intramuscular (IM) routes, to investigate the pathogenesis of 5 Russian isolates of African Swine Fever Virus (ASFV) collected in 2013. Several clinical and virological parameters (including hemorrhagic syndrome, body fever and gross and microscopic lesions) were identical between the high and low dose groups for all 5 isolates, whereas duration of pyrexia, incubation period and clinical phase of infection differed between the high and low doses and between the 5 isolates. Additionally, pigs inoculated with high ASFV doses had the shortest mean survival time. A subsequent contact challenge experiment demonstrated that IN- and IM-inoculated pigs were able to transmit ASFV via direct contact with non-infected pigs.
Finally, our experiments indicated that these Russian ASFV isolates possessed variable pathogenicity. The isolates from wild boars had the lowest virulence and extended disease duration as compared to those from domestic pigs.
Most of the Gordonia species described earlier have been considered as opportunistic pathogens in humans, but recently described species have been isolated from the environment with notable roles in bioremediation or the biodegradation of pollutants. A gram-positive slightly acid-fast nocardioform bacterium, strain SD256 (DSM 45847), was isolated from a granulomatous lymph node of a zebu cow at Kaduqli, western Sudan, was subjected to a polyphasic taxonomic study. The strain was found to have morphological, biochemical and chemotaxonomic properties that were consistent with its assignment to the genus Gordonia. Although the strain exhibited some phenotypic variations from the type strain of Gordonia sinesedis, 16S rRNA gene sequencing (accession: KC895879) and DNA-DNA relatedness showed 100% and 99.6% similarity, respectively. Microbiologic diagnoses of fastidious actinomycetes such as Gordonia species are often difficult and challenging. However, the combined phenotypic and genotypic data confirm that this strain is a member of Gordonia sinesedis, which represents a first record of Gordonia infection in farm animals.
Background: Methicillin-resistant Staphylococcus aureus (MRSA) infections have been recognized for decades as hospital acquired MRSA (HA-MRSA). Nowadays, MRSA is also recognized as a worldwide emerging community-associated pathogen. Community associated-MRSA (CA-MRSA) has been shown to be more virulent with a high degree of severity of disease when compared to HA-MRSA.
Objectives: The study was designed to assess the occurrence and the molecular detection of HA-MRSA and CA-MRSA isolates obtained from clinical specimens in Iraq.
Methods: HA-MRSA and CA-MRSA isolates were obtained from clinical specimens in three main hospitals in Hilla city/Iraq during the period, March to June 2011. MRSA isolates obtained primarily from clinical specimens of skin and soft tissue infections (SSTs) were subjected to genetic study. PCR was used for detection of genes responsible for methicillin resistance (mecA, SCCmec type IV) and genes responsible for toxin production (pvl, lukED). Statistical analysis was performed using chi-square (X2) test to assess intergroup significance, inpatients, and outpatients with respect to all genes used in present study.
Results: Out of 301 clinical samples, 24 MRSA isolates were obtained. All these MRSA isolates (100.0%) were mecA gene positive. Twenty three (95%) were found to be carrying SCCmec type IV, 19 (79%) had positive result for pvl toxin gene, and 20 (83%) had lukED toxin gene.
Conclusion: The majority of MRSA isolates belonged to SCCmec IV. pvl and lukED toxin genes are also found in the MRSA isolates among the CA-MRSA isolates
Steinhausia mytilovum (Field, 1924) is a microsporidian parasite that infects female individuals of Mediterranean mussel, Mytilus galloprovincialis. The aim of this work was to evaluate the incidence and histopathological effect of the microsporidian in the host from the Atlantic coast of northwest Africa. Samples were collected monthly during two years (March 2009 - March 2011) at three sites; north, middle and south, along the Moroccan coast. The prevalence showed to be the highest in the north (0% - 26.66%) and south (0% - 75%), respectively, while mussels from the middle sampling site showed no infection of S. mytilovum. The seasonality of S. mytilovum was investigated as well, although no significant variation of its incidence was observed in respect to season. The most usual histopathological characteristic of the S. mytilovum infection was hemocytic infiltration in gonads, showing a statistically significant relationship to the S. mytilovum infection (P<.001). Further investigation is recommended to study influences of the biological and physical parameters on the infections of S. mytilovum in the natural populations of the Mediterranean mussel along the Moroccan coast.
Aim: The aims of the study were to determine the antibacterial resistance profile and detect the presence of antibacterial resistance genes of Salmonella isolates recovered from the blood samples of hospitalized subjects in Kano metropolis.
Study Design: The study is a descriptive cross-sectional study.
Place and Duration of Study: One milliliter of venous blood was collected from each patient with some or all clinical features of salmonellosis that sign a consent form and transfer into EDTA bottles. If daily is unavoidable blood samples were stored at 4°C. Samples were analyzed at the both Laboratories of the authors. This work was carried out between May, 2011 and March, 2013.
Methodology: The blood specimens were cultured in thioglycollate broth and sub-cultured onto deoxycholate citrate agar (DCA), Salmonella-Shigella agar (SSA) and brilliant Green agar (BGA) followed by confirmation of presumptive colonies using different biochemical tests and analytical profile index 20E. Serologic identification of Salmonella was performed by slide agglutination test using polyvalent O and H Salmonella antisera. Antibacterial drug susceptibility studies were performed by the disc diffusion method using ampicillin, chloramphenicol, ciprofloxacin, nalidixic acid and Trimethoprim-sulfamethoxazole. Out of one hundred and four salmonellae isolates obtained in this study, twenty one were subjected to DNA extraction, real-time and multiplex polymerase chain reaction (PCR) using various primer sets targeting the specific sequences of the resistance genes.
Results: Of the 104 isolates 96 (92.3%) were resistant to Ampicillin; 81 (77.9%) resisted to Nalidixic acid; 30 (30.8%) resisted to Chloramphenicol, 17(16.3%) resisted to Cotrimazole while none (1.0%) resisted to Ciprofloxacine. Among the thirteen Salmonella isolates tested by real-time PCR, Tem gene was detected with a higher frequency (38.5%) compared to the gyrB gene (30.8%). In addition, four Salmonella isolates were found to harbour both tem and gyrB genes together with 30.8%. In this study, no gyrA gene amplicon was obtained, although one Salmonella Typhi strain was resistant to ciprofloxacin phenotypically. There was significant correlation between the presence of tem and/or gyrB and resistance to ampicillin and nalidixic acid. However, in this study, out of the eight Salmonella isolates tested by multiplex PCR technique, sul2 gene was detected in two (25.0%) isolates and catP gene was detected in one (12.5%); while the amplification of these two genes failed in five Salmonella isolates (62.5%) and no isolate harboured both sul2 and catP genes. There is no significant correlation between the presence of sul2 /catP and resistance to chloramphenicol and cotrimoxazole.
Conclusion: Most Salmonella serovars isolated from patients in Kano, Nigeria resisted to Ampicillin. They also resisted to Nalidixic acid, Chloramphenicol and Cotrimazole, in decreasing order. Ciprofloxacine remained effective against all the Salmonella isolates tested. Almost all the genes tested were circulating within Kano metropolis, including tem, gyrB, sul2 and catP genes with exception of gyrA. There was only significant correlation between the presence of tem and/or gyrB and resistance to ampicillin and nalidixic acid.
Aims: Production of amino acids from black strap sugar cane molasses by Bacillus sp. R22EG1 strain and Bacillus sp. R20EG2 using batch and fed-batch (pulsed and continuous feeding) cultures was investigated to achieve the maximum concentration of free amino acids.
Place and Duration of Study: Department of Agricultural Microbiology, Faculty of Agriculture, Ain Shams University, Cairo, Egypt, between December 2011 and March 2012.
Methodology: Two Bacillus strains namely R22EG1 and R20EG2, were used as amino acid produces. The amino acid producing bacteria were grown in the bioreactor with batch and fed-batch cultivation. The fed-batch fermentations were performed in two strategies using pulsed and continuous feeding of black strap sugar cane molasses. In the first strategy (fed-batch by pulsed feeding), the amount of black strap sugar cane molasses (50 ml.L-1) was added to the fermentation vessel. Two, three and four additions of this amount of black strap sugar cane molasses were also added during the first 12 and 48 h of cultivation periods. In the second strategy, the black strap sugar cane molasses was fed continuously during the first 12, 18 and 24 h of cultivation periods at rates of 4.17, 2.78 and 2.08 ml.L-1.h-1, respectively (fed-batch by continuous feeding). The cell dry weight, amino acid concentration and residual sugar were determined as well as the growth and production parameters were calculated.
Results: The biological activity of Bacillus sp. R22EG1 and Bacillus sp. R20EG2 strains during production of amino acids on 5% black strap sugar cane molasses medium for 72 h at 30°C was investigated in bioreactor as a batch and fed-batch cultures. In batch culture, the highest figures of amino acid concentration (2.30 and 2.83 g.L-1), yield (9.52 and 11.71%), and conversion coefficient (11.09 and 13.44%) were recorded after 72 h and 60 h of fermentation periods by Bacillus sp. R22EG1 and R20EG2 strains, respectively, whereas the maximum productivity, approximately, 0.044 and 0.059 g.L-1.h-1 were observed after 12 h and 24 -36 h for Bacillus sp. R22EG1 a nd R20EG2 strains, respectively. Two feeding strategies (pulsed and continuous) were studied during production of amino acids using fed-batch culture. The highest cell dry weight, amino acid concentration and yield were recorded after three pulsed molasses addition during the first 12 h of fermentation periods with specific addition rate of 0.204 ml.L-1.h-1 (0.099 g.L-1.h-1 sugar) for the tested strains. The continuous feeding rate of 4.17 ml.L-1.h-1 (2.01 g.L-1.h-1 sugar) was more favorable than pulsed feeding during 12 h for amino acid production in fed-batch culture, as it increased the amino acid concentration by Bacillus sp. R22EG1 and R20EG2 strains, approximately, (1.53 & 1.42) fold than pulsed feeding and about (1.64 & 1.59) fold than that produced in batch bioreactor technique, after a 48 h fermentation period. The highest content of free amino acid species in culture supernatants was glutamic acid produced by both strains.
Conclusion: The maximum production of amino acids from continuous fed–batch by Bacillus sp. R22EG1 strain and Bacillus sp. R20EG2 was 3.76 and 4.49 g.L-1 with continuous feeding at 4.17 ml.L-1.h-1 (2.01 g.L-1.h-1 sugar) at 48 h, respectively. These results were 1.53 & 1.42 fold higher than pulsed feeding and 1.64 & 1.59 fold higher than batch fermentation by Bacillus sp. R22EG1 and R20EG2 strains, respectively. The highest content species of free amino acids was glutamic acid using a Bichrom 30 amino acid analyzer
Aims: To isolate lipase producing fungi from soil samples and study the effect of nutritional factors on lipase production by the isolated fungi.
Study Design: Lipase producing fungi were isolated from oil contaminated soil samples. Different carbon, nitrogen and lipid sources and their different concentrations were tested for optimum lipase production. T-test and ANOVA were performed to validate the results.
Place and Duration of the Study: Department of Biotechnology, National Institute of Technology, Raipur, From February to August, 2012.
Methodology: Isolation of lipase producing fungi from oil contaminated soils was done using Saboraud’s agar medium. Identification of isolated fungi was done by Division of Plant Pathology, Indian Agriculture Research Institute, New Delhi. Different sources and concentrations of carbon, nitrogen and lipids (inducers) were tested for optimization of extracellular lipase production. Lipase assay was performed by photometric method. Tukey’s test and one way ANOVA tests were performed to validate the results obtained.
Results: Three fungi isolated in the study were Aspergillus ochraceous, Aspergillus fumigatus and Penicillium purpurogenum. Culture amendments study indicated that maximum lipase activity for A. ochraceous was reported with 0.5% maltose as carbon source and 0.5% peptone as nitrogen source. For A. fumigatus sucrose at 1.0% was the best carbon source, while soybean meal at 1.5% as nitrogen source reported maximum lipase activity. For P. purpurogenum maximum lipase activity was reported with 1.5% sucrose as carbon source and 1.5% peptone as nitrogen source. Tween 80 at 1.0% was the best inducer for all the three isolates.
Conclusion: Lipase producing fungi were isolated from oil contaminated soils and culture amendments study was done to optimize extracellular lipase production.
Malaria is caused by the protozoan parasites of genus Plasmodium.Plasmodium falciparum is the most common cause of malaria in Africa and South-East Asia. In India, Plasmodium vivax has been the primary pathogen responsible for malaria, even though Plasmodium falciparum cases are on the rise in recent times. We develop a mathematical model ShE1E2E3I1I2I3RSh of malaria in human population with vertical transmission for Plasmodium vivax, Plasmodium falciparum and co-infection of both Plasmodium vivax and Plasmodium falciparum parasites and SmEmIm model in mosquito population. The stability of the system under different conditions for disease–free equilibrium and endemic equilibrium are established. Extensive numerical simulations are carried out to establish the analytical results with real parametric values and sensitivity analysis of basic reproduction number is also carried out with the transmission probability for malaria in human population. Finally, we compare all three infected classes of Plasmodium vivax, Plasmodium falciparum and co-infection of both the parasites with real value parameters by numerical simulation and also calculated its basic reproduction numbers.