Aims: Control of microbial pathogens by using antagonistic microorganisms is a promising alternative to chemical fungicides. The objective of the present study was to isolate and characterize soil actinomycetes and to their inhibitory activity against some fungal plant pathogens. Place and Duration of Study: National Park “El Chico”, Hidalgo State, and Laboratory of the Southeast Unit of CIATEJ, Yucatán, México, between June 2010 and May 2011. Methodology: Actinomycete species were isolated from six composite soil samples using microbiological standard procedures. All isolates were phenotypically characterized. Antagonistic isolates were selected according to the inhibitory growing of Fusarium sp. and Candida albicans. Afterwards, a new evaluation for the isolates selected was done against Helminthosporium sp., Curvularia sp., and Aspergillus niger. Actinomycetes were identified performing an analysis of the 16S rDNA gene sequence. Results: 164 actinomycete strains were characterized by morphological and biochemical features. Six of them, inhibited the growth of Fusarium sp. and C. albicans from 5 to 10 mm distance in between the actinomycete´s colony growth border of fungal or yeast. A growing reduction from 50 to 83 % in the in vitro antagonism assays was observed for Helminthosporium sp., Curvularia sp., and Aspergillus niger. Results in disc diffusion assays suggested an inhibitory growing capacity of CACIA-1.46HGO for P. capsici, this behavior could be due to the production of diffusible compounds related to secondary metabolism, hydrolytic enzymes, or both of them. Four antagonistic isolates were identified into Streptomyces genus and one as Microbacterium sp. through 16S rDNA gene sequence. Conclusion: Actinomycetes could be potentially a control tool to prevent several fungal commercial plants diseases. However, in situ isolate evaluations are suggested to be investigated.
Aim: This study was aimed at determining the number of children infected in relation to study population. Study Design: Cross sectional Place and Duration of Study: This study was conducted among school children in Gadabuke and Garagwa LGEA Primary schools in Toto Local Government Area of Nasarawa State, Nigeria between October-December, 2012. Materials and Methods: A total of 250 samples were collected comprising 192 urine and 58 faecal samples. Samples were investigated using standard World Health Organisation guidelines for identification of parasites. Samples were analysed macroscopically and microscopically. Results: Out of the 192 children screened. Gadabuke LGED primary school had a prevalence of 58.1% while Garagwa LGED primary school had a prevalence of 22.7% and the overall prevalence of urinary schistosomiasis in the two schools is 44.3%. There was no significant difference in prevalence rate of urinary schistosomiasis between Gadabuke and Garagwa primary schools (P>0.05). On the other hand, Gadabuke had a prevalence of 5.3% for S.mansoni and 0% prevalence for Garagwa LGED. On the whole, the prevalence of S. mansoni was 3.4% in the study area. Children of age group (8 – 14) were more infected with urinary schistosomiasis. Male had higher prevalence of urinary schistosomiasis 50 (50%) than the female 35 (35%). Statistically there was significance difference in prevalence infection of Schistosoma haematobium among males and females investigated. Children whose parents are farmers and fishermen had the highest prevalence infections, followed by Artisan, civil servant and the businessmen. Conclusion: Urinary schistosomiasis in some selected primary schools in Gadabuke district of Toto LGA in Nasarawa State have been documented.
Aims: Emergence of antibiotic resistance and extended spectrum β- lactamase (ESBL) among uropathogens in the pediatric unit of hospitals created serious health care concern. This study deals with antimicrobial susceptibility and ESBL analysis of uropathogenic Escherichia coli isolated from children hospitalized in pediatric unit of a university hospital in Kerman, Iran. Methodology: Fifty-five uropathogens positive samples were recovered from one hundred thirty five samples collected from urine of the children hospitalized with sign of UTI in pediatric unit of a hospital, in Kerman, Iran from April 2011 to November 2012. Preliminary antimicrobial susceptibility testing was carried out using agar disk-diffusion breakpoint assay and minimum inhibitory concentrations (MICs) of different antibiotics were determined by agar dilution method. ESBL production was detected by a double disk synergy test and confirmed by a phenotypic confirmatory test. Results: Of fifty-five positive samples isolated, Escherichia coli (69%) was the leading uropathogen followed by Klebsiella spp. (18.8%), Proteus (7.27%), Staphylococcus aureus (3.63%), Citrobacter (1.8%), Enterobacter spp. (1.81%) and Enterococcus (1.8%). Antimicrobial susceptibility tests revealed that almost all uropathogenic E. coli were sensitive to carbapenems (100%) and amikacin (94.4%), while, 100% of the strains were resistant to ampicillin (MIC range ±32 µg/mL), 63.8% were resistant to amoxicillin/clavulanic acid (MIC range ±32µg/mL), 33% were resistant to trimethoprim- sulfamethoxazole (MIC range ±64.2µg/mL) and 61.1% of the strains were resistant to third generation of cephalosporins (MIC range ±8.0µg/mL) (P=0.05). The ESBL confirmatory test for uropathogenic E. coli isolates resistant to third generation of cephalosporins revealed that only 20% were produced detectable ESBL enzymes. Conclusion: From above results it can be concluded that E. coli was the most common nosocomial pathogen associated with UTI among hospitalized children in our hospital and amikacin, carbapenems were very effective drugs for treatment of UTI in these age group, while, care must be taken when third generation of cephalosporins and trimethoprim- sulfamethoxazole are administered.
Aim: To study the presence of indoor mycoflora in A/c Buses to know the commuters risk of exposure to fungal spores. Place and Duration: Chennai Mofussil Bus Terminus (CMBT), Koyambedu, Chennai, India. Study was conducted from November 2011 to April 2012. Methodology: Airborne fungi from 50 A/c buses were studied using Reuter Centrifugal Sampler (Biotest, Germany), fungi from the surfaces of air vents through swab sample and bus seats by rubbing sterile petridishes on the seats. Sabourauds Dextrose Agar (SDA) was used for the isolation of fungi from different buses. The collected data were statistically analyzed. Results: A total of 38 species classified in 21 genera were recorded. Among which, Zygomycetes was represented by 4 species, Ascomycetes and Coelomycetes by single species each and the remaining belongs to Hyphomycetes. The genus, Aspergillus was represented by maximum number of species (11 species) followed by Penicillium (5 species). A total average of 713 CFU/m3 of air was recorded within the buses. Aspergillusniger was the first dominant fungi in the order of dominance followed by Chrysonilia sitophila, Alternaria alternata and Aspergillus flavus in that order. From the surface of bus seats, Aspergillus niger, A. flavus, Rhizopus stolonifer and A. japonicus were recorded as dominant. However, different mycofloral composition was recorded from air vents. Cladosporium chlorocephalum and Curvularia lunata dominated the surface of air vents. Conclusion: The study demonstrates the presence of potential fungal species which pose exposure risk to the immune compromised commuters.
Background: Brucellosis is a major zoonotic disease that is endemic in Saudi Arabia and it remains a major health problem that has not been eradicated in the country yet. Place and Duration of Study: This retrospective study was conducted in a Saudi Hospital at Al Madinah city during the period of 1 November, 2010 to 31 October, 2011. Methodology: All sera of patients suspected to have brucellosis (n= 65) and 18 healthy subjects were tested for brucella antibody using slide latex agglutination (SAT) and ELISA. Quantitation of IFN-É£ was also done using ELISA. Results: Brucellosis was detected in all age groups but the incidence was higher and reached 33.3% in age group (40- <50) years with average of 43.9±2.53 years. Male to female ratio in infected patients was 2:1 by using SAT. The incidence of seropositive cases was high (80.1%) in the three months (April, May and June), with the highest peak in May (46.7%). Drinking raw milk was the most encountered risk factor with a prevalence of 66.1% followed by consumption of milk products (11.9%). The most prevalent species among the examined cases was B. melitensis (93.3%). Among the studied cases, 60 cases (92.3%) were serologically positive for brucellosis by SAT. Among the 60 cases yielding significant titers against brucella, 14 sera (23.3%) had agglutinin levels of 1:80, 34 sera (56.7%) had titers of 1:160 and 12 sera (20%) had titers of 1:320. By estimating IgM and IgG levels in the sera of examined cases using ELISA, 52 cases (80%) had brucellaIgM while 42 cases (64.6%) had brucella IgG. Sensitivities of SAT, IgM ELISA and IgG ELISA were 91.5%, 88.1% and 71.2%, respectively compared with combined ELISA. Mean IFN-É£ levels ± SD in the subacute phase was 136.7±70.07pg/ml, 120.2±54.25pg/ml in the acute phase, and 121.3±51.09 pg/ml in the chronic phase of brucellosis. Conclusion: The sensitivity and specificity of ELISA to diagnose human brucellosis was higher when combined ELISA (IgM/IgG or both) was used. Mean IFN-É£ levels were lower, but not significantly, in the chronic phase of the disease than in the sub acute phase and healthy subjects.
Aims: To determine the prevalence of Legionella spp. in domestic hot water systems and evaluate the molecular diversity among these Legionella spp. Isolates. Place and Duration of Study: Sample collection area was the city of Aqaba, Jordan, between May and December 2012. Sample analysis was done in Ben-Hayyan international laboratories, Aqaba city, and the molecular microbiology laboratories, Taibah University, Saudi Arabia. Methodology: Two hundred (200) water samples were collected randomly from hot water tanks of private apartments, and were tested for the occurrence of Legionella spp. using direct membrane filtration method followed by species identification using Gram stain, the API 20NE biochemical system and the Legionella species latex agglutination test. Genotype characterizations of the Legionella isolates was carried out using DNA extraction followed by RAPD-PCR amplification with OP-A3 primer and analysis of the resulting patterns. Results: Of the 200 samples, 17 (8.5%) were positive for the presence of Legionella spp. A total of 15 (88.2%) out the 17 positive samples were confirmed as Legionella pneumophila, 10 of them were of serogroup 1 and 5 isolates were of serogroup 2-14, the remaining two isolate were Legionella species other than L. pneumophila. RAPD-PCR analysis classified all 17 Legionella isolates into three groups. Serogroup 1 isolates were classified into group A, serogroup 2-14 isolates in group B and Legionella spp. isolates in group C. Group A was further sub-clustered into two subgroups, genotype A1 containing isolates collected from hot water tanks of a temperature set at 25-30°C and A2 containing isolates collected from hot water tanks of a temperature set at 55-80°C. Conclusion: This study showed the colonization of the plumbing systems of private houses by Legionella spp. and demonstrated that the temperature of the water tanks maybe one of the most important factors that affect the genotypic behavior of Legionella pneumophila.
Milk has good quality protein and is a unique substance in that it is consumed as fluid milk with minimal processing and also it is the raw material used to manufacture a wide variety of products. Milk is susceptible to contamination by many pathogenic microorganisms, which result in infection and threat to consumer’s health. The aim of this study was to determinate occurrence of pathogenic microorganisms in raw milk in four seasons from different locations in Egypt, the obtained counts results showed that the samples gave the lowest Total Plate Count (TPC) of 3x105cfu/ml in winter’s samples. While, the summer's sample showed the highest TPC of 5.8x107cfu/ml. E. coli count ranged from 2x102cfu/ml to 5.8x 105cfu/ml which the lowest count was noticed in winter’s samples. Staphylococcal count ranged from 2.7 x 103cfu/ml (winter sample) to1.28 x 106cfu/ml (another sample in the same season). These results indicated poor hygienic standard of raw milk from uncontrolled environments and the increased public health risk of those consuming raw milk from such uncontrolled sources and all these tests consume time but with Culture-independent methods that are based on protocols where total DNA (or RNA) is directly extracted from the substrate it can save time. Coupled with a global analysis, these methods make it possible to study the total diversity from the bulk extract in a single step.
Aim: The aim of this study was to ascertain the effect of temperature on nutrient uptake ability of four bacterial species. Methodology: A total of four bacterial species (Klebsiella sp., Pseudomonas sp., Lysinibacillus sp. and Staphylococcus sp.) were used for the study. The media used for the investigation was synthetic wastewater. Four different temperatures (25ºC, 30ºC, 35ºC and 40ºC) were used for the investigation. The study was carried out under shake flasks conditions. Immediate after inoculation with the respective test bacterial species and every 24 h for a 96 h incubation time, aliquot wastewater samples were removed from the flasks for the estimation of total phosphate, nitrate, pH and growth rate, using standard procedures. Results: The results revealed phosphate and nitrate removal ranges of 10.84 % to 55.55 % and 90.67 % to 97.27 %, respectively in the presence of the Klebsiella sp. In the presence of the Pseudomonas sp, Lysinibacillus sp. and Staphylococcus sp., phosphate removals ranges of 0.36 % to 46.98 %, 11.89 % to 50.80 % and 2.74 % to 51.21 % were observed, respectively. For nitrate concentrations, removal levels that ranged from 2.19 % to 92.95 %, 0.97 % to 23.12 % and 7.56 % to 91.66 % were observed in the presence of Pseudomonas sp, Lysinibacillu ssp. and Staphylococcus sp., respectively. All the test bacterial species showed some measure of efficiency in phosphate removal. For nitrate removal, the Lysinibacillus sp. did not exhibit remarkable nitrate removal ability at any of the temperatures. In addition, the optimum temperatures for phosphate removals were observed to be 30ºC to 40ºC for the Klebsiella sp. and Pseudomonas sp; and 30ºC to 35ºC for the Lysinibacillus sp. and Staphylococcus sp. For nitrate removal, optimum temperatures for removal were observed to be 25ºC to 40ºC, for the Klebsiella sp and 25ºC to 35ºC, for the Pseudomonas sp. and Staphylococcus sp. Conclusion: The study was able to reveal the optimum temperatures for phosphate and nitrate uptake in synthetic wastewater by the test bacterial species.
Aims: To study storage rots in yam varieties cultivated in South East Nigeria and to determine under conditions of experimental storage, the influence of fungal rot on their post harvest storage losses. Place and Duration of Study: Laboratories, Department of Applied Microbiology & Brewing, Nnamdi Azikiwe University, Awka, Nigeria between January 2012 and July 2013. Methodology: Five yam varieties; Dioscorea dumentorum, two varieties each of D. alata and D. rotundata, obtained immediately after harvest were stored in an experimental barn (30ºC and 95% RH) and examined at intervals for storage rots. Fungal causative agents of rots were isolated and identified using the partial ITS rDNA sequencing analysis and a BLAST search using the GenBank sequence database. Post harvest storage losses in terms of weight loss and reduction of shelf life among the varieties were determined. Results: All varieties of yams studied suffered fungal rots, predominantly, dry rots during storage. Seven distinct fungal isolates, which caused these rots, were fully characterized. The species were Aspergillus tamari, Fusarium solani, Lasiodiplodia theobromae, Aspergillus niger, Mucor circinelloides, Aspergillus flavus and Aspergillus sp. In all the yams, storage rots reduced shelf life and aggravated weight loss. Post harvest storage losses varied among the different varieties of yams. Conclusion: The varieties of yams studied suffer rots from various fungi, which are similar to those reported in other parts of the world. Severity of post harvest losses resulting from fungal rots varies among different varieties of yams. This should be taken into consideration in the development of storage techniques.
Aims: This study was focused on using Lactic Acid Bacteria (LAB) isolated from fresh vegetables which has been molecularly identified for in vitro control of some tomato pathogens. Study Design: The inhibitory potentials of supernatant obtained from previously characterized LAB isolates or vegetable origin were investigated against some tomato phytopathogens using agar-well method with the view to develop biological agents for some tomato disease causing organisms. Place and Duration of Study: Biotechnology Centre of Federal University of Agriculture, Abeokuta, Ogun State, Nigeria, between January 2011 and February 2012. Methodology: The antimicrobial activities of LAB against some tomato phytopathogenic bacteria which include (Xanthomonas campestries, Erwinia caratovora, and Pseudomonas syringae) were obtained by using the agar well diffusion method. Results: The result indicates that cell free culture of LAB from fresh vegetables origin (Weissella paramesenteroides, Lactobacillus pentosus, Weissella cibaria, Pediococcus pentosaceus, Weissella kimchi and Lactobacillus plantarum) can inhibits these bacteria by creating clear zones of inhibition around the wells containing cell free supernatants of the above mentioned strains of lactic acid bacteria. Pediococcus pentosaceus showed the highest zone of inhibition against Xanthomonas campestries at 15 mm radius, Weissella kimchi was the least effective against Pseudomonas syringae at 3.67 mm and Erwinia caratovora at 3.50 mm radius. Conclusion: Tomato disease causing organisms can be most likely biologically controlled by using extracts from LAB. This finding will reduce the potential hazard from the use of chemical herbicides on plant.