Colony-forming Units Per Gram Research Articles

Efficacy of a Fixed Combination of Tetracycline, Chloramphenicol, and Colistimethate Sodium for Treatment of Candida albicans Keratitis

To evaluate the antifungal activity of a fixed antibiotic combination (AC) containing tetracycline (TET), chloramphenicol (CAF), and colistimethate sodium (CS). In vitro: Candida ATCC and clinical strains were used. The minimum inhibitory concentrations (MICs) of AC and of each antibiotic were determined. Fluconazole (FLC) was tested for comparison. Time-killing curves of selected strains were performed. Ex vivo keratitis: corneas were injected intrastromally with the selected strains. After the injection, corneas were divided into groups of treatments: AC, FLC, or saline. Then, the tissues were analyzed for colony-forming units per gram (CFU/g). Propidium iodide (PI) and MitoTracker (MTR) staining were used to investigate the mode of action. Values of MIC required to inhibit the growth of 90% of organisms for the antibiotics alone were higher than FLC. However, their activity was enhanced when used in combination against Candida yeasts. Time-killing curves showed that at 24 hours, AC reduced the load of both strains of approximately 1 Log10 CFU/g compared with the initial inoculum (P < 0.0001). This effect was also significant versus FLC. In ex vivo, AC was effective in decreasing the loads of both strains by 4 Log10 CFU/g with respect to the control. Moreover, it showed higher activity than FLC against Candida albicans ATCC 10231 (1 Log10 CFU/g, P < 0.01 versus control). PI staining demonstrated that CS changed the membrane's permeability, whereas MTR staining demonstrated that TET or CAF altered mitochondrial function. The cells treated with AC and stained showed both effects. In this study, AC showed antifungal efficacy versus Candida spp.; this activity can be due to the synergistic effects of antibiotics in it.

Microbiological quality of commercially available poultry feeds sold in Bangladesh

The study was conducted aiming at the isolation and identification of pathogens from poultry feed manufactured by four different brands namely A (broiler starter), B (broiler finisher), C (layer starter) and D (layer finisher) sold in retail stores of Rangpur city of Bangladesh. All these samples were collected from four randomly chosen outlets and analyzed by culturing in different culture media such as Nutrient broth (NB), Nutrient agar (NA), Salmonella-Shigella (SS) agar, Eosin methylene blue (EMB) agar, MacConkey agar, Triple sugar iron (TSI) agar slant, Motility, Indole, Urease (MIU) and Saboraud Dextrose agar (SDA) media. The bacterial agents were isolated and examined under light microscope for their gross morphological and conventional biochemical characteristics. The bacteriological analyses were done at the Microbiology Laboratory of Hajee Mohammad Danesh Science and Technology University, Dinajpur during the period of January to June, 2014. Total bacterial colonies of all the samples were counted separately according to the American Public Health Association, using nutrient agar medium for total viable count (TVC), Eosine methylene blue (EMB) agar media for total E. coli count (TEC) and Salmonella-Shigella agar for TSC (total salmonella count). Saboraud Dextrose agar (SDA) media was used for detection of fungus. The virulence effect of the organism present in feed were observed by inoculating the organism in poultry. Recorded result showed that average TVC of feed sample A, B, C and D were 5.45x106, 3.28x105, 5.14x106 and 4.53x105 CFU/gm (colony forming unit per gram) respectively. TEC of feed sample A, B, C and D were recorded 6.25x105, 8.26x103, 5.52x105 and 5.65x104 CFU/gm respectively. TSC of feed sample A, B, C and D were recorded 3.15x104, 2.68x103, 4.46x103 and 1.19x104 CFU/gm respectively. The highest TVC, TEC and TSC were found in broiler starter (feed sample A) and lowest TVC, TEC and TSC were found in broiler finisher (feed sample B). Fungal count was 1.85x105 CFU/ gm in layer finisher (feed sample D) could be as a result of their high pathogenecity as reported by researchers elsewhere. These organisms can cause several poultry and farm animal infections specially mycotoxicosis having public health significance to both human and poultry. The presence of high numbers of E. coli and Salmonella spp. in poultry feed were indicative of poor hygienic practices during manufacture, post process contamination and unsatisfactory transportation and reservation. Therefore reinforce the need for preventive control measures, hygienic handling and processing of feeds to reduce the risk of potential human health hazards.Asian J. Med. Biol. Res. March 2017, 3(1): 52-60

Dietary Effect of Probiotic Bacteria, Bacillus amyloliquefaciens-JFP2 on Growth and Innate Immune Response in Rock Bream Oplegnathus fasciatus, Challenged with Streptococcus iniae

The present study was conducted to evaluate the use of Bacillus amyloliquefaciens as a probiotic source in the diet of rock bream, Oplegnathus fasciatus. A total of 210 fingerlings (25.4 ± 0.13 g) were divided into two groups, three replicates each; control (C) and probiotic (P) group (35×3=105 fish per group). C group was fed a basal diet without probiotic while P group was fed with B. amyloliquefaciens spores at a concentration of 1.4 ×106 colony-forming units per gram (CFU/g) of feed. After 90 days, P group fish showed significant improvements in body weight (BW), weight gain (WG), specific growth rate (SGR) and food conversion ratio (FCR) when compared with C group fish. Also, in bi-weekly assessments, serum protein and glucose level showed a significant increase (p&lt;0.05) in probiotic fed fish compared with the control group. Similar increase in serum antioxidant and lysozyme activity was found in the probiotic fed fish group. However, there was a significant decrease in triglyceride and total cholesterol along with increased alanine aminotransferase (ALT) and aspartate amonotransferase (AST) levels in probiotic diet fed fish compared to the control. After seventy days the fish were challenged with Streptococcus iniae and mortality of the probiotic fed fish was significantly lower (p&lt;0.05) when compared with the control. These results demonstrate the benefit of incorporation of B. amyloliquefaciens as a feed supplement to improve the health status of Oplegnathus fasciatus challenged with Streptococcus iniae.

Dietary Effect of Probiotic Bacteria, Bacillus amyloliquefaciens-JFP2 on Growth and Innate Immune Response in Rock Bream Oplegnathus fasciatus, Challenged with Streptococcus iniae

The present study was conducted to evaluate the use of Bacillus amyloliquefaciens as a probiotic source in the diet of rock bream, Oplegnathus fasciatus. A total of 210 fingerlings (25.4 ± 0.13 g) were divided into two groups, three replicates each; control (C) and probiotic (P) group (35×3=105 fish per group). C group was fed a basal diet without probiotic while P group was fed with B. amyloliquefaciens spores at a concentration of 1.4 ×106 colony-forming units per gram (CFU/g) of feed. After 90 days, P group fish showed significant improvements in body weight (BW), weight gain (WG), specific growth rate (SGR) and food conversion ratio (FCR) when compared with C group fish. Also, in bi-weekly assessments, serum protein and glucose level showed a significant increase (p&lt;0.05) in probiotic fed fish compared with the control group. Similar increase in serum antioxidant and lysozyme activity was found in the probiotic fed fish group. However, there was a significant decrease in triglyceride and total cholesterol along with increased alanine aminotransferase (ALT) and aspartate amonotransferase (AST) levels in probiotic diet fed fish compared to the control. After seventy days the fish were challenged with Streptococcus iniae and mortality of the probiotic fed fish was significantly lower (p&lt;0.05) when compared with the control. These results demonstrate the benefit of incorporation of B. amyloliquefaciens as a feed supplement to improve the health status of Oplegnathus fasciatus challenged with Streptococcus iniae.

Bacteriological Quality of Street Foods and Antimicrobial Resistance of Isolates in Hawassa, Ethiopia.

Microbial contamination of ready-to-eat foods and beverages sold by street vendors and hawkers has become an important public health issue. In Ethiopia, health risks related to such kinds of foods are thought to be common. Thus, this study has tried to determine the bacteriological quality of ready- to- eat foods sold on streets. A cross-sectional study was conducted on street foods in Hawassa City from May to September 2014. A total of 72 samples from six food items such as local bread ('ambasha' and 'kita'), raw fish, chilli ('awaze'), avocado and cooked potato were collected. Bacterial isolation, colony count and antimicrobial susceptibility testing were made following standard microbiological techniques. About 31% of the food samples showed total colony counts ranging from 1.7×105 to 6.7×106 colony-forming unit per gram (CFU/g) which is beyond the acceptable limits set for microbiological quality of ready- to -eat foods. The mean coliform and Enterobacteriaceae counts in raw fish, 'kita' and 'ambasha' were also higher than the limits. E.coli was the most frequent isolate (29.6%) followed by Salmonella species (12.7% and S.aureus (9.9%). All isolates were 100% sensitive to ciprofloxacin. About 89% of Salmonella sp was resistant to chloramphenicol. Alarmingly, 14.3% of S.aureus was resistant to vancomycin. This study confirmed considerable rate of contamination in street vended foods in Hawassa City. The identified foodborne bacteria and antibiotic resistance isolates could pose a public health problem in that locality. Therefore, regular inspection, health education and training of vendors on food handling and safety practices are recommended.

A novel approach for quality maintenance and shelf life extension of fresh-cut Kajari melon: Effect of treatments with honey and soy protein isolate

Effect of treatments with different concentrations of honey (0 mL/L of water, 50 mL/L of water, 100 mL/L of water, 150 mL/L of water) followed by coating with soy protein isolate (50 g/L of water) on fresh-cut Kajari melons was investigated. Effect of honey separately without soy protein isolate coating was also investigated. The treatments were given prior to packing the samples in polypropylene trays and stored at 4 °C for sensory and overall shelf life studies. A total of eight combinations of samples with three replicates each were analyzed for various quality attributes throughout the storage life. Highest weight loss occurred in untreated melon samples. Sample treated with 150 mL honey/L of water +50 g SPI/L of water maintained highest total soluble solids throughout the storage. Sensory scores below 5 were given to control sample after day 8 of storage. Samples treated with honey (150 mL/L of water) showed better results in terms of most of the sensory characteristics. Ripening index decreased remarkably over the storage period with control sample reaching lowest values in comparison to treated samples. Total plate count of 9.63 log colony forming units per gram (CFU/g) for control sample and counts of less than 5 log CFU/g for treated samples were observed at the end of the storage.

Improvement of immunity and disease resistance in the Nile tilapia, Oreochromis niloticus, by dietary supplementation with Bacillus amyloliquefaciens

Probiotics can be used as immunostimulants in aquaculture. The aim of this study was to evaluate the immune responses of Nile tilapia Oreochromis niloticus following feeding with Bacillus amyloliquefaciens spores at concentrations of 1 × 106 (G3) and 1 × 104 (G2) colony-forming units per gram (CFU/g) of feed compared with a basal diet with no probiotics (G1). A total of 180 fingerlings (27.7 ± 0.22 g) were divided into three groups (G1–G3 of 20 fish per group) in triplicate. Innate immunities were measured every two weeks based on serum bactericidal activity, lysozyme activity, a nitric oxide assay (mmo/l) and phagocytic activity, and the expressions of interleukin-1 (IL-1) and tumor necrosis factor alpha (TNF α) were examined after one month. Moreover, the survival of tilapia upon challenge with Yersinia ruckeri or Clostridium perfringens type D was determined at the end of feeding trial. After 15 d, the serum killing percentages and phagocytic activities were significantly higher in G3 than in G1 and G2, whereas the same parameters had significantly higher values in G3 and G2 than in G1 after 30 d. After both 15 d and 30 d, the lysozyme activities and nitric oxide assay results (mmo/l) were significantly higher in G3 than G2, and the lowest values were observed in G1. The percentage of serum killing, serum nitric oxide and serum lysozyme activity were significantly increased by the time of B. amyloliquefaciens administration independently of the probiotic dose, and the phagocytic activity percentage was significantly decreased at the end of the experiment. Dietary B. amyloliquefaciens caused significant increases in IL-1 and TNF α mRNA levels in the kidneys in the following pattern: G3 > G2 > G1. Fish that were fed B. amyloliquefaciens exhibited better relative survival percentages than the controls when challenged by Y. ruckeri or C. perfringens type D. Dietary supplementation with B. amyloliquefaciens improves immune status and disease resistance in Nile tilapia.

Monitoring fungal growth on brown rice grains using rapid and non-destructive hyperspectral imaging

This research aimed to develop a rapid, non-destructive, and accurate method based on hyperspectral imaging (HSI) for monitoring spoilage fungal growth on stored brown rice. Brown rice was inoculated with a non-pathogenic strain of Aspergillus oryzae and stored at 30°C and 85% RH. Growth of A. oryzae on rice was monitored using viable colony counts, expressed as colony forming units per gram (CFU/g). The fungal development was observed using scanning electron microscopy. The HSI system was used to acquire reflectance images of the samples covering the visible and near-infrared (NIR) wavelength range of 400–1000nm. Unsupervised self-organizing map (SOM) was used to visualize data classification of different levels of fungal infection. Partial least squares (PLS) regression was used to predict fungal growth on rice grains from the HSI reflectance spectra. The HSI spectral signals decreased with increasing colony counts, while conserving similar spectral pattern during the fungal growth. When integrated with SOM, the proposed HSI method could be used to classify rice samples with different levels of fungal infection without sample manipulation. Moreover, HSI was able to rapidly identify infected rice although the samples showed no symptoms of fungal infection. Based on PLS regression, the coefficient of determination was 0.97 and root mean square error of prediction was 0.39 log (CFU/g), demonstrating that the HSI technique was effective for prediction of fungal infection in rice grains. The ability of HSI to detect fungal infection at early stage would help to prevent contaminated rice grains from entering the food chain. This research provides scientific information on the rapid, non-destructive, and effective fungal detection system for rice grains.

Development of fermented and flavoured kefir milk

Kefir is a dairy beverage, obtained from lactic acid and alcoholic fermentation of its grains, which resembles yogurt in its flavour, aroma and consistency. It is composed of approximately 15-16 lactobacilli, approximately 7-9 streptococci/lactococci, 8 yeasts and 2 acetic bacteria (acetobacter). The fermenting action of Kefir bacteria and yeasts increases the biological value of milk, increasing synthesis of the B group vitamins, which help in the digestive process. The abundance in Calcium, Phosphor, and Magnesium is another of Kefir's characteristics, as for all other dairy products. It is an easily digested product that eliminates harmful bacteria and yeasts from the intestine, increases beneficial and protective bacterial population, and as a probiotic food has many therapeutic applications. This study had as its objective the production of fermented milk based on Kefir, when different flavours were tested, to have it sensorial tested to find the one with the highest acceptance. Firstly, an analysis of the total coliform content was performed, followed by a microbiological quantification analysis of the colony-forming-unit per gram (CFU/g), to ensure the quality of the product to be offered to tasters. Secondly, the Kefir milk was flavoured with 4 different flavours (passion fruit, strawberry, grape and mango), where juice from concentrate pulp and fruit bits were used, served to 60 tasters (students, professors and staff from UNISO), according to the model for rank-preference test (164/IV 'Testes Efetivos - Testes de preferencia' Effective Test - PreferenceTests) according to the Instituto Adolfo Lutz.

Surgical debridement alone does not adequately reduce planktonic bioburden in chronic lower extremity wounds.

It is commonly believed that sharp surgical debridement provides adequate bacteria control for local wound beds, despite limited supporting scientific evidence. We undertook a prospective study to evaluate the reduction in planktonic bacteria pre- and post-operative debridement in critically colonised wounds. Twelve patients, corresponding to 14 wounds, underwent debridement with either hydrodebridement or sharp steel debridement with pulse irrigation. Wound quantitative tissue cultures were taken pre- and post-debridement. There was no significant difference in wound aetiology or surface area between the two groups. TThe bacterial counts before debridement were 1×107 colony-forming units per gram (CFU/g) in the hydrodebridement group vs 1.4×107 CFU/g in the sharp debridement group; and 2.5×106 CFU/g (hydrodebridement) vs 7.5×105 CFU/g (sharp) after debridement (p=0.41). The total bacteria reduction was 7.5×106 CFU/g after hydrodebridement vs 1.3×107 CFU/g after sharp steel debridement (p=0.37). The mean percentage of bacteria killed from baseline was 75% by hydrodebridement and 93% killed by sharp debridement (p<0.05). Extensive operative debridement using either modality does not provide adequate immediate reduction in wound planktonic bioburden. However, all wounds appeared clinically appropriate for closure after debridement and postoperative antibacterial therapy. Postoperative antibacterial therapy may be imperative in cases of critically colonised wounds to achieve good outcomes. The senior author receives research grant support from Healthpoint Biotherapeutics; KCI; Manuka Honey; Smith & Nephew; Medline Ind., Macrocure; CODA. In addition the senior author is a consultant for: Smith & Nephew and KCI and medical consultant and reviewer for Macrocure. While the study as presented evaluates in part the efficacy of a commercial product from Smith & Nephew, no industry support for this study was sought or provided.

Evaluation of Bacillus amyloliquefaciens on the growth performance, intestinal morphology, hematology and body composition of Nile tilapia, Oreochromis niloticus

Probiotics are dietary microbial supplements used as alternatives to antibiotics in aquaculture. The present study was performed to evaluate the use of Bacillus amyloliquefaciens as a probiotic bacteria in the diets for Nile tilapia, Oreochromis niloticus. A total of 180 fingerlings (9.4 ± 0.3 g) were divided into three groups (G1–G3 of 20 fish per group) in triplicate. G1 was fed a basal diet with no probiotic as the control group, while G2 and G3 were fed B. amyloliquefaciens spores at concentrations of 1 × 104 and 1 × 106 colony-forming units per gram (CFU/g) of feed, respectively. After 30 days, G3 showed significant improvements in body weight (BW), weight gain (WG), specific growth rate (SGR) and food conversion ratio (FCR) compared with G1 and G2. At the end of the feeding period (60 days), both G2 and G3 had significantly higher FBW, WG, SGR, FCR and protein efficacy ratio compared with the control. The increase in the probiotic level in the diet increased the heights of the intestinal villi, especially in the proximal part of the intestine. In G3, the proximal and distal parts had significantly higher numbers of mucus-secreting cells (goblet cells) than in G2 and G1. There were significantly more intra-epithelial lymphocytes (IEL) in the intestine in G3 compared with the control in all parts of the intestines, whereas G2 had significantly more IELs than the control in only the distal part of the intestine. B. amyloliquefaciens had no harmful effects on glucose levels, and increased the erythrocyte and leukocyte counts, hemoglobin content and hematocrit. High levels of the probiotic (G3) had better effects than lower levels (G2) on serum total protein and globulin levels. The protein contents of the whole body in G3 and G2 were higher than those of the control group. The highest body fat content was recorded in G3, followed by G2. These results indicate that the use B. amyloliquefaciens as a feed supplement is beneficial to O. niloticus.

Effect of Gamma Radiation on Growth and Mycotoxin Production of Alternaria alternata

The ubiquitous genus Alternaria contains many species that are able to invade cereals, oleaginous plants and other crops. Alternaria alternata is considered one of the most important species and can produce several mycotoxins under favorable conditions of temperature and humidity, including the economically important toxins: alternariol (AOH) and alternariol monomethyl ether (AME). The aim of this study was to evaluate the radio-sensitivity of Alternaria alternata spores through different gamma radiation doses. A. alternata growth and the production of AOH and AME were then analyzed. After fungal irradiation with 2 kGy, 5 kGy and 7 kGy, the spores were suspended with sterile distilled water followed by inoculation on wheat grains. The count of the colony-forming units per gram (CFU/g) was performed using Dichloran Rose Bengal Chloramphenicol (DRBC) and Dichloran Chloramphenicol Agar Malt Extract (DCMA); AOH and AME were analyzed using Liquid Chromatography coupled with Mass Spectrometer (LC-MS). Results showed that fungal growth and toxin production increased with the increase of radiation dosage. The implications of these findings in relation to the resistance of A. alternata spores to gamma irradiation are discussed.

Avaliação do padrão estafilococos coagulase positiva estabelecido pela legislação brasileira para massas alimentícias

A multiplicacão de Staphylococcus aureus e a produção de enterotoxinas estafilocócicas dependem de fatores intrínsecos e da temperatura de armazenamento dos alimentos. O objetivo deste trabalho foi discutir o padrão estafilococos coagulase positiva (ECP) para massas alimentícias, estabelecido pela RDC n.º 12 de 2001 da ANVISA, baseando-se nos resultados de atividade de água (a w), potencial hidrogeniônico (pH) e contagem de ECP. Cinquenta amostras de 25 tipos de massas de treze marcas diferentes foram analisadas. A contagem de ECP de todas as amostras foi menor que 10 Unidades Formadoras de Colônia por grama (UFC/g), inferior a 5,0 × 10³ UFC/g, estabelecido como limite máximo pela legislação. As médias de a w das massas secas com e sem recheio variaram entre 0,70 e 0,61, respectivamente, o que impossibilita a multiplicação de ECP e produção de toxina. Por outro lado, a média de a w das massas frescas foi de 0,96, o que propicia o desenvolvimento desse padrão microbiológico. Os resultados obtidos neste trabalho indicam que a a w poderia ser utilizada como parâmetro para determinar em quais tipos de massas o padrão ECP deveria ser pesquisado, ou seja, para massas alimentícias cruas que possibilitassem a multiplicação de Staphylococcus spp. (a w &gt; 0,86).

Development of probiotic beads similar to fish eggs

Probiotic foods are mainly restricted to dairy and soy products. This study aimed to develop a new probiotic beads similar to fish eggs, commonly used in oriental cuisine. Beads were produced by the extrusion encapsulation technique with calcium alginate, added to one of the following cultures: Lactobacillus rhamnosus GG ATCC 53103 and Bifidobacterium animalis DN-173 010 and stored for 30 days at 4°C. The beads were characterized by the size, weight, morphology and viability of the probiotic strains in different storage temperatures and in simulated gastric juice adjusted to different pH values. The beads were also evaluated by a sensorial affective hedonic scale. The beads present a 2.8mm diameter and a weight of 0.01g (p>0.05). Free and encapsulated cells were tolerant to pH 3.0. At pH 2.5 only of the encapsulated cells presented counts above 6Log colony-forming units per gram (CFU/g). Beads containing L. rhamnosus showed higher viability 107CFU/g in storage for 30days under refrigeration. The beads may be stored at abusive temperature for 5h without loss of viability cells. The probiotic product developed showed an 82.2% acceptability index of overall characteristics and good market potential as a new probiotic product.

Influence of Osmotic Stress and Encapsulating Materials on the Stability of Autochthonous Lactobacillus plantarum after Spray Drying

With the aim of producing a functional fish food, autochthonous Lactobacillus plantarum LPS 47, isolated from healthy Chilean salmon, was stabilized using spray drying. In order to increase the resistance of microorganisms to high temperatures, osmotic stress during fermentation and different protective agents were evaluated (lactic solids: skim milk and whey, maltodextrin, pectin, and arabic gum). We found that bacteria that were not exposed to osmotic stress during culture, and that were spray-dried in the presence of cheese whey (20% w/w) as a protective material, gave the best results in terms of viability, humidity, and stability during storage. Dehydrated material reached a viability of approximately 109 CFU/g (colony-forming units per gram) and less than 5% humidity, values that were maintained over 10 weeks of storage at 4°C in a non-controlled atmosphere. Results show that it is possible to obtain a stable dehydrated probiotic product, with high concentration of microorganism, using spray drying and whey as a protective agent, without causing osmotic stress, by harvesting the biomass during the stationary phase.

Listeria monocytogenes in ready-to-eat, sliced, cooked ham and salami products, marketed in the city of São Paulo, Brazil: Occurrence, quantification, and serotyping

The preference for ready-to-eat sliced foods may pose an increased risk for food-borne diseases, and a major concern is the presence of Listeria monocytogenes. L. monocytogenes was assessed in two types of products: cooked ham and salami. One hundred and thirty samples of each product were acquired in retail shops in the city of São Paulo and submitted to laboratory analysis. The rate of positives was significantly higher in salami samples than in ham samples (6.2% and 0.8%, respectively). L. monocytogenes counts in salami samples varied between <10 and 1900 colony-forming units per gram (CFU/g). The serotypes found in both products were as follows, according to incidence: 4b (37.5%), 1/2b (25%), 3b (25%), and 1/2c (12.5%). Based on the results of the present study, the authors suggest that the risk of listeriosis resulting from the consumption of salami is higher than that associated with the consumption of cooked ham.

Microbiological Quality of Ice Cream Sold in Gilgit Town

Ice cream is a food commonly consumed during summer. It harbors many potent pathogens, its microbial quality especially bacteriological quality has always been crucially important to public health. This study aims to access bacteriological quality of ice cream sold in different areas of Gilgit town. Randomly collected ice cream samples were studied to determine the microbiological load or colony forming units per gram (CFU/g) using the standard aerobic plate count method. All samples showed positive growth of bacteria ranging from 2.2 X 10 to 8-2 X 10 CFU/g. Seven bacterial species were isolated. The highest 3 4 frequency of isolation was Escherichia coli 20 (100%) and least isolation was Salmonella spp. 3 (15%). For confirmation the colonies were tested biochemically and were identified up to specie level.

Ammoniation of rice straw using poultry litter: Effect on nutrient composition and patholgenic microbial flora

La valeur nutritive et la flore microbienne pathogene de la paille de riz traitee a la litiere de volaille dans un essai factoriel 5x3x3 a ete evaluee a l’Universite Abubakar Tafawa Balewa, a Bauchi, au Nigeria. La paille de riz a ete melangee avec la litiere de volaille (RSPL) dans cinq proportions differentes 5:5, 6:4, 7:3, 8:2 et 9:1. L’eau a ete melangee avec chacun des RSPL (1-5) dans trois proportions differentes, 50:50, 60:40 et 70:30, respectivement. Les melanges ont ete conserves dans des futs metalliques etanche pendant 7, 14 et 21 jours.. La masse microbienne par gramme (UFC/g) etait significativement (P facon significative (P The nutritive value and pathogenic microbial flora of poultry litter treated rice straw in a 5x3x3 factorial trial was conducted at the Abubakar Tafawa Balewa University, Bauchi, Nigeria. Rice straw was mixed with poultry litter (RSPL) in five different ratios; 5:5, 6:4, 7:3, 8:2 and 9:1. Water was mixed with each of the RSPL (1-5) in three different proportions; 50:50, 60:40 and 70:30 respectively. The mixtures were kept in air-tight metal drums for treatment periods of 7, 14 and 21 days respectively. The colony forming unit per gram (CFU/g) was significantly (P while the CF and CFU/g decreased with days of treatment. It may be concluded that treating rice straw with poultry litter can improve the nutritive value while at the same time reduce the pathogenic microorganisms of the treated straw. An equal proportion of crop residue to poultry litter with an equal amount of water is required to enhance treatment. Treatment period of 21 days is required for effective treatment making the material safe for feeding to livestoc.

Effects of gamma radiation on the growth of Alternaria alternata and on the production of alternariol and alternariol monomethyl ether in sunflower seeds

The objective of the present study was to evaluate the effects of different gamma radiation doses on the growth of Alternaria alternata and on the production of toxins alternariol (AOH), and alternariol monomethyl ether (AME) in sunflower seed samples. After irradiation with 2, 5 and 7 kGy, the spore mass was resuspended in sterile distilled water and the suspension was inoculated into sunflower seeds. The number of colony-forming units per gram (CFU/g) was determined after culture on Dichloran Rose Bengal Chloramphenicol and Dichloran Chloramphenicol Malt Extract Agar. The presence of AOH and AME was investigated by liquid chromatography coupled to mass spectrometry. The radiation doses used resulted in a reduction of the number of A. alternata CFU/g and of AOH and AME levels when compared to the nonirradiated control group. Maximum reduction of the fungus (98.5%) and toxins (99.9%) was observed at a dose of 7 and 5 kGy, respectively. Under the present conditions, gamma radiation was found to be an alternative for the control of A. alternata and, consequently, of AOH and AME production in sunflower seeds.

Detección de Yersinia pseudotuberculosis en heces de cuyes (Cavia porcellus) utilizando una metodología microbiológica y una molecular

En este trabajo se evaluó el desempeño de dos metodologías, una microbiológica y una molecular basada en la amplificación por reacción en cadena de la polimerasa (PCR), para la detección de Yersinia pseudotuberculosis en heces de cuyes. La evaluación de cada una de las metodologías se realizó teniendo en cuenta su sensibilidad y especificidad analítica, así como su costo económico, tiempo y complejidad. La detección molecular de Y. pseudotuberculosis se realizó por PCR anidada usando iniciadores específicos para el gen de virulencia cromosomal inv, mientras que en los ensayos microbiológicos la identificación bacteriana se hizo mediante una batería comercial de perfiles bioquímicos. Se estandarizó un protocolo de amplificación en materia fecal, el cual redujo el efecto negativo que causan los inhibidores de la PCR presentes en muestras de esta naturaleza. La sensibilidad analítica más alta se observó con la metodología en la que se combinó preenriquecimiento, aislamiento microbiológico y PCR, con un rango de detección entre 1,5 x 104 y 1,5 x 103 unidades formadoras de colonias por gramo (ufc/g) de material fecal; mientras que la mayor sensibilidad obtenida en PCR anidada fue de 1,5 x 105 ufc/g de materia fecal. Tanto la metodología microbiológica como la molecular presentaron ventajas en los ensayos en los que se usó materia fecal estéril experimentalmente inoculada. Sin embargo, en muestras de materia fecal sin esterilizar la detección del microorganismo se dificultó al utilizar una única metodología, por lo que se sugiere combinar técnicas microbiológicas y moleculares para obtener un mejor desempeño diagnóstico.