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Ginkgo Biloba (GB) is a widely used finished herbal product. Due to its natural source there is no demand to evaluate its quality before marketing. Although GB products have shown promising potential with the efficacy, many of these products remain untested. The Current work aims to evaluate some quality parameter of GB finished products like total flavonoid content (TFC), microscopic, Loss On Drying (LOD) and microbial tests in comparison with GB crude plant. The TFC ranged from (22.86 to78.74 mg/g). Microscopic findings revealed the presence of large amounts of starch grains in product A. Furthermore, most of the products were heavily contaminated with bacteria and fungi. As bacterial colony counts ranged from (103 to 7.5 × 105 CFU/g) and from (1.7 × 103 to 0.75 × 107 CFU/g) for fungal colony counts. Most of the products exceeded the reference limits for LOD. thus may pose a threat to consumer's health.

A forecasting model to predict the kiwifruit bacterial canker infections was developed in New Zealand. In 2012, we started the validation of such forecasting in the kiwifruit growing areas of Emilia-Romagna Region. Validation was carried over 2012-2014, exposing micro-propagated potted kiwi plantlets under untreated infected plants from march until November and check them for symptom occurrence, along with pathogen isolation on selective growing media and PCR determination on isolated bacterial colony. Over the years 2012-2014, symptoms on plantlets were always observed from March to the first week of June. In the same period, disease symptoms occurred in the untreated kiwifruit adult vines, confirming what observed in potted trap plants. However diagnostic analysis showed that bacteria can be detected in potted trap plants throughout the year (particularly in 2013 and 2014), except some sporadic week during summer even without a rain event. Validation experiment using trap plants allowed to validate the forecasting model during springtime (from March to June) showing a robust correspondence between the model prediction and the symptom occurrence as well as the bacterial inoculum contaminating the trap plants during the growing season.

Lumbricus rubellus earthworm is known having antioxidant and antibacterial properties such as Polyphenolic, Glycoprotein G-90, and Lumbricin I. These substances also work as hepatoprotective agents in the parenchymal cell damage due to infection. This study aims to determine the antioxidant properties of earthworm extract (Lumbricus rubellus) in reducing the levels of ALT, AST, and a number of the bacterial colony in male Wistar rats infected by Salmonella thypimurium as a model of S.typhii infection. Posttest-only control group design method was carried out in 28 samples which divided into 4 treatment groups. The blood samples were taken for the ALT and AST measurement on day 18. The bacterial colony measurement was conducted by growing the bacteria in the feces with Total Plate Count (TPC) method. The ALT levels in T2 were significantly decreased (P

Purpose: This study aimed to evaluate the antibacterial effect of Apple Vinegar as a root canal irrigant using Endovac irrigation System. Materials and Methods: for this study, 60 extracted human teeth were used. After their decapitation, they were instrumented using Universal ProTaper rotary files up to size F4 then separated into 2 set of groups according to the solution used in irrigation; Group A1: irrigated with 5.25 NaOCl Group A2: irrigated with Apple vinegar (30 specimens in each group). We then subdivided each group into 2 subgroups according to the technique used for irrigation; Subgroup A: using conventional irrigation and Subgroup B: using Endovac irrigation system. Samples were sterilized and inoculated with Enterococcus faecalis (ATCC29212) for 48 hrs. After irrigation, microbial samples were collected, transferred to nutrient agar and incubated for counting of bacterial colony forming units (CFUs). The significance level was P≤ 0.05. Results: There was a statistically significant difference among the tested groups and subgroups in the mean scores of bacterial counts. Concerning the irrigating devices, there was statistically significant difference between conventional irrigation and Endovac system as Endovac showed higher antibacterial effect than conventional irrigation (P ≤ 0.05). Apple vinegar showed statistical significant difference with Endovac system subgroup than conventional irrigation (P ≤ 0.05). Conclusion: Endovac irrigation system was effective in eradication of E. faecalis from the root canals using either NaOCl or Apple vinegar.

Flying fish (Decapterus Sp.) Is one of the by-products that is still underutilized into processed products that have economic value, even though the potential is quite high. Processing of fish with a fermentation process has several products, one of which is the manufacture of fish sauce. While the addition of salt can maintain the shelf life of fish sauce This study aims to determine the comparison of the number of bacterial colony found in Decapterus Sp overcooked fish sauce treated with pineapple and salt. This research was conducted at the Applied Laboratory of Marine Products Processing Technology and at the Basic Polytechnic Laboratory of Palu. The method used in this research is descriptive analysis method. Bacterial identification and business analysis are carried out qualitatively and quantitatively. The highest number of microbes was obtained in fish sauce without using 10% pineapple and 7% salt which was 2.2 x 105 and the lowest was found in fish sauce using 10% pineapple and 7% salt which was 0.3 x 105 and for feasible economic analysis to be marketed because it still has a profit of Rp. 1,900. the conclusion is that fish sauce that uses 10% pineapple and 7% salt is suitable for consumption and marketing and suggestions for further testing for the shelf life of flying fish sauce are added 10% pineapple and 7% salt.

Many species of bacteria have developed means to spread on solid surfaces. This study focuses on the expansion of Pseudomonas aeruginosa on an agar gel surface. We report the occurrence and spread of a depletion zone, where the layer of bacteria on the agar becoming thinner. The depletion zone occurs within an expanded colony under conditions of minimal water evaporation. It is colocalized with a higher concentration of rhamnolipids, the biosurfactants that are produced by the bacteria and accumulate in the older region of the colony. With continued growth in bacterial population, dense droplets occur and coalesce in the depletion zone, displaying remarkable fluid dynamic behavior. Whereas expansion of a central depletion zone requires activities of live bacteria, new zones can be seeded by adding rhamnolipids. These depletion zones due to the added surfactants expand quickly, even on plates covered by bacteria that have been killed by ultraviolet light. We propose a model to account for the observed properties, taking into consideration bacterial growth and secretion, osmotic swelling, fluid volume expansion, cell-cell interaction, and interfacial fluid dynamics involving Marangoni flow.SignificanceBacterial growth and pattern formation have strong bearing on their biological functions, such as their spread and accumulation, biofilm growth & its effects on infection and antibiotic resistance. The bacterial species of this study, Pseudomonas aeruginosa, is a human pathogen responsible for frequent infections in wounds, airways, and urinary tract, particularly when involving the use of catheters. The findings of this study and the mechanisms we propose offer new insights on the important behaviors of bacterial collective motility, pattern dynamics, and biofilm growth.

Phenotypic heterogeneity occurs in a population of genetically identical bacteria due to stochastic molecular fluctuations and environmental variations. In extreme cases of phenotypic heterogeneity, a fraction of the bacterial population enters dormancy, and these metabolically inactive or non-dividing bacteria persist through most antibiotic challenges. These subpopulations of persister cells are difficult to study in patient samples. However, the proportion of persisters in a sample can be accessed by physically separating bacteria on a plate measuring the time until colonies become visible as dormant bacteria resume growth later than their active counterparts and form smaller colonies.Here, we present ColTapp (Colony Time-lapse app), an application dedicated to bacterial colony growth quantification, freely available for download together with its MATLAB source code or as a MacOS/Windows executable. ColTapp’s intuitive graphical user interface allows users without prior coding knowledge to analyze endpoint or time-lapse images of colonies on agar plates. Colonies are detected automatically, and their radius can be tracked over time. Downstream analyses to derive colony lag time and growth rate are implemented.We demonstrate here the applicability of ColTapp on a dataset of Staphyloccocus aureus colony time-lapse images. Colonies on dense plates reached saturation early, biasing lag time estimation from endpoint images. This bias can be reduced by considering the area available to each colony on a plate.By facilitating the analysis of colony growth dynamics in clinical settings, this application will enable a new type of diagnostics, oriented towards personalized antibiotic therapies.

Rhinology studies anatomy, physiology and diseases affecting the nasal region: one of the most modern techniques to diagnose these diseases is nasal cytology or rhinocytology, which involves analyzing the cells contained in the nasal mucosa under a microscope and researching of other elements such as bacteria, to suspect a pathology. During the microscopic observation, bacteria can be detected in the form of biofilm, that is, a bacterial colony surrounded by an organic extracellular matrix, with a protective function, made of polysaccharides. In the field of nasal cytology, the presence of biofilm in microscopic samples denotes the presence of an infection. In this paper, we describe the design and testing of interesting diagnostic support, for the automatic detection of biofilm, based on a convolutional neural network (CNN). To demonstrate the reliability of the system, alternative solutions based on isolation forest and deep random forest techniques were also tested. Texture analysis is used, with Haralick feature extraction and dominant color. The CNN-based biofilm detection system shows an accuracy of about 98%, an average accuracy of about 100% on the test set and about 99% on the validation set. The CNN-based system designed in this study is confirmed as the most reliable among the best automatic image recognition technologies, in the specific context of this study. The developed system allows the specialist to obtain a rapid and accurate identification of the biofilm in the slide images.

We report a highly-sensitive, high-throughput, and cost-effective bacteria identification system which continuously captures and reconstructs holographic images of an agar-plate and analyzes the time-lapsed images with deep learning models for early detection of colonies. The performance of our system was confirmed by detection and classification of Escherichia coli, Enterobacter aerogenes, and Klebsiella pneumoniae in water samples. We detected 90% of the bacterial colonies and their growth within 7-10h (>95% within 12h) with ~100% precision, and correctly identified the corresponding species within 7.6-12h with 80% accuracy, and achieved time savings of >12h as compared to the gold-standard EPA-approved methods.

Bacterial infections are a serious issue for many implanted medical devices. Infections occur when bacteria colonize the surface of an implant and form a biofilm, a barrier which protects the bacterial colony from antibiotic treatments. Further, the anti-bacterial treatments must also be tailored to the specific bacteria that is causing the infection. The inherent protection of bacteria in the biofilm, differences in bacteria species (gram-positive vs. gram-negative), and the rise of antibiotic-resistant strains of bacteria makes device-acquired infections difficult to treat. Recent research has focused on reducing biofilm formation on medical devices by modifying implant surfaces. Proposed methods have included antibacterial surface coatings, release of antibacterial drugs from surfaces, and materials which promote the adhesion of non-pathogenic bacteria. However, no approach has proven successful in repelling both gram-positive and gram-negative bacteria. In this study, we have evaluated the ability of superhydrophobic surfaces to reduce bacteria adhesion regardless of whether the bacteria are gram-positive or gram-negative. Although superhydrophobic surfaces did not repel bacteria completely, they had minimal bacteria attached after 24 h and more importantly no biofilm formation was observed.

The purpose of this research to determine the level on the quality of pork jerky (aroma, texture and TPC). The research design used was a complete random design (CRD) with 4 treatments and 3 replications, and continued with Mann-Whitney test. The sensoric data used hedonik test according to Kruskal-Wallis method. The treatment consisted of R0 = without roselle flour, R1 = roselle flour 5g, R2 = roselle flour 10g and R3 = roselle flour 15g. The results showed that the addition of roselle flour 5g, 10g and 15g gave a significant difference (P 0,05). But the best texture value is at the level of 10g roselle flour. Conclusion, The level of roselle flour influences the value of the aroma of jerky and can reduce the total bacterial growth in the pork jerky. The best activity level of 15g roselle flour can reduce the lowest total bacterial colony.

Since the hypermucoviscous variants of Klebsiella pneumoniae were first reported, many cases of primary liver abscesses and other invasive infections caused by this pathogen have been described worldwide. Hypermucoviscosity is a phenotypic feature characterized by the formation of a viscous filament ≥5 mm when a bacterial colony is stretched by a bacteriological loop; this is the so-called positive string test. Hypermucoviscosity appears to be associated with this unusual and aggressive type of infection, and therefore, the causal strains are considered hypervirulent. Since these first reports, the terms hypermucoviscosity and hypervirulence have often been used synonymously. However, new evidence has suggested that hypermucoviscosity and hypervirulence are 2 different phenotypes that should not be used synonymously. Moreover, it is important to establish that a negative string test is insufficient in determining whether a strain is or is not hypervirulent. On the other hand, hypervirulence- and hypermucoviscosity-associated genes must be identified, considering that these phenotypes correspond to 2 different phenomena, regardless of whether they can act in synergy under certain circumstances. Therefore, it is essential to quickly identify the genetic determinants behind the hypervirulent phenotype to develop effective methodologies that can diagnose in a prompt and effective way these hypervirulent variants of K. pneumoniae.

Detection of the biofilm of bacteria would be a counter strategy to detect hidden bacteria in their camouflage. Through unbiased screening of bacteria biofilm, we discovered a long wavelength probe CDr15 with extracellular DNA as the molecular target. CDr15 revealed a real-time geometric distribution of eDNA in a 3D bacterial colony.

Milk losses associated with mastitis can be attributed to either effects of pathogens per se (i.e. direct losses) or to effects of the immune response triggered by the presence of mammary pathogens (i.e. indirect losses). Test-day milk somatic cell counts (SCC) and number of bacterial colony forming units (CFU) found in milk samples are putative measures of the level of immune response and of the bacterial load, respectively. Mediation models, in which one independent variable affects a second variable which, in turn, affects a third one, are conceivable models to estimate direct and indirect losses. Here, we evaluated the feasibility of a mediation model in which test-day SCC and milk were regressed toward bacterial CFU measured at three selected sampling dates, 1 week apart. We applied this method on cows free of clinical signs and with records on up to 3 test-days before and after the date of the first bacteriological samples. Most bacteriological cultures were negative (52.38%), others contained either staphylococci (23.08%), streptococci (9.16%), mixed bacteria (8.79%) or were contaminated (6.59%). Only losses mediated by an increase in SCC were significantly different from null. In cows with three consecutive bacteriological positive results, we estimated a decreased milk yield of 0.28 kg per day for each unit increase in log2-transformed CFU that elicited one unit increase in log2-transformed SCC. In cows with one or two bacteriological positive results, indirect milk loss was not significantly different from null although test-day milk decreased by 0.74 kg per day for each unit increase of log2-transformed SCC. These results highlight the importance of milk losses that are mediated by an increase in SCC during mammary infection and the feasibility of decomposing total milk loss into its direct and indirect components.

In this study, a series of enrichment tests were conducted to investigate the effectiveness of two enriching media on the indigenous ureolytic bacteria in Hawaiian coastal beach sand. Sand collected from the intertidal zone of the Kailua Beach was used in the study, which was subjected to the erosion action of wave and tide periodically. Two media applied were YE (yeast extract only) and YEU medium (yeast extract with urea). Shaking incubation test was conducted up to 72 h to stimulate the indigenous ureolytic bacteria. The pH, ammonium concentration, ureolytic activity, and viable bacterial colony number of the enriched bacterial solution were measured at 6 h, 12 h, 24 h, 48 h and 72 h respectively. Results show that the primary stimulation occurred within the first 48 h. The concentration of ammonium ions and ureolytic activity were significantly increased and the viable bacterial colony number was slightly decreased at the end of the enrichment. These observations indicate that the ureolytic bacteria resided in the intertidal zone can be enriched effectively.

Purpose – The aim of this study is to determine the differences in the antimicrobial activity of katuk leaf (Sauropus androgynus (L.) Merr) against Escherichia coli. Design/Methodology/Approach – The method used in this study was experimental posttest using a control group design. Analysis of the effect of katuk leaf was performed in the dilution method with 20%, 40%, 60%, 80%, and 100% concentration. The data were analyzed using one-way ANOVA test (α = 0.05) and was then tested using the least significant difference (LSD) test. Findings – Bacterial colony counting that used total plant count found the average of E. coli amount at 20% of concentration (526.820 CFU/ml), 40% of concentration (449.380 CFU/ml), concentration of 60% (255.710 CFU/ml), concentration of 80% (194.110 CFU/ml), and at concentration 100% (168.600 CFU/ml). This study concluded that the katuk leaf extract at 20%, 40%, 60%, 80%, and 100% of concentration had antimicroba effect with significant influence. The 100% of concentration had the most significant effect compared with the other concentrations. Research Limitations/Implications – Katuk leaf could be used as one of the alternative herbal choices that has a compound antimicrobial effect. Originality/Value – This study increases the theoretical understanding of the difference of antimicrobial effectivity of katuk leaf extract (S. Androgynus (L.) Merr.) concentration against E. coli

16SrDNA PCR-DGGE was used to reveal the dynamics of bacterial colony and identify the predominant bacteria in liquid-smoked tilapia during storage at 25°C. Total bacteria DNA was directly extracted from the tilapia fillets. By analysis of the community changes directly obtained from the DGGE profiles, the predominant bacteria were found to bePediococcus pentosaceus,Clostridium sp.andLactococcusgarvieae. Simultaneously, culture method was performed., 34 strains of 70 colonies were picked up from samples of day 4 storage period, then 6 strains were picked up at random and identified by extracting their 16SrDNA and sequencing, it’s proved that they were allLactococcus. So Two ways of identifying the predominant bacteria were almost consistent.

Detection of carbapenemase-producing Enterobacteriaceae (CPE) is an important task at microbiology laboratories in hospitals. As the prevalence of CPE is increasing worldwide, the implementation of phenotypically based screening as well as confirmatory procedures to detect CPE are important for microbiologists. In addition to detection of carbapenem hydrolysis, the inhibition of activity against a carbapenem in the presence of several inhibitor compounds specific to class A, B, or class C beta-lactamases is a useful method to confirm the presence of carbapenemases in bacterial isolates. There is also a proteomic approach that compares the MALDI-TOF spectrum generated by the intact carbapenem (non-hydrolyzed) with that obtained after hydrolysis of the beta-lactam ring by beta-lactamase to reveal the presence of carbapenemases in bacterial isolates. Proteomic methods will probably be more frequently implemented in laboratories in the near future. Finally, molecular methods to directly or indirectly detect the presence of a carbapenemase genes are increasingly being used in microbiology laboratories. One of the main advantages of these methods is their speed, and also that they can be used directly with the clinical sample without the need for an isolated bacterial colony. Multiplex PCR, real-time PCR, DNA microarrays and pyrosequencing are some examples of molecular-based tests. Their main disadvantage is their cost, although prices are going down as the range of services increases. Surveillance of carriers is also an important task for infection control purposes. In this case, commercially available chromogenic medium supplemented with low carbapenem concentrations has shown an excellent ability to detect CPE. Moreover, molecular methods to detect specific carbapenemase genes directly from rectal swabs, stools, or other colonization sources have had excellent results.

Colonies are an abundant form of bacterial multicellularity; however, relatively little is known about the initial stages of their construction. We have previously described that colony development of the soil bacterium Bacillus subtilis is a highly ordered process, typically initiating with the formation of extending cell chains arranged in a Y shape structure. Furthermore, we demonstrated that Y arm extension is a key for defining the size of the future colony. Here we conducted a genetic screen surveying for mutants deficient in these early developmental stages, and revealed LtaS, the major lipoteichoic acid (LTA) synthase, to be crucial for execution of these events. We found that the ltaS mutant fails to produce proper Y shape structures, forming extremely elongated chains of cells with no evidence of chain breakage, necessary for Y shape formation. Furthermore, we show that frequent cell death at the tips of the cell chains is a major cause in limiting arm extension. Collectively, these perturbations lead to the production of a small sized colony by the mutant. Thus, deficiency in LTA synthesis causes a mechanical failure in executing the colony developmental program.

Background and Objective: The recent introduction of Full Laboratory Automation systems in clinical microbiology opens to the availability of streams of high definition images representing bacteria culturing plates. This creates new opportunities to support diagnostic decisions through image analysis and interpretation solutions, with an expected high impact on the efficiency of the laboratory workflow and related quality implications. Starting from images acquired under different illumination settings (top-light and back-light), the objective of this work is to design and evaluate a method for the detection and classification of diagnostically relevant hemolysis effects associated with specific bacteria growing on blood agar plates. The presence of hemolysis is an important factor to assess the virulence of pathogens, and is a fundamental sign of the presence of certain types of bacteria. Methods: We introduce a two-stage approach. Firstly, the implementation of a highly accurate alignment of same-plate image scans, acquired using top-light and back-light illumination, enables the joint spatially coherent exploitation of the available data. Secondly, from each segmented portion of the image containing at least one bacterial colony, specifically designed image features are extracted to feed a SVM classification system, allowing detection and discrimination among different types of hemolysis. Results: The fine alignment solution aligns more than 98.1% images with a residual error of less than 0.13 mm. The hemolysis classification block achieves a 88.3% precision with a recall of 98.6%. Conclusions: The results collected from different clinical scenarios (urinary infections and throat swab screening) together with accurate error analysis demonstrate the suitability of our system for robust hemolysis detection and classification, which remains feasible even in challenging conditions (low contrast or illumination changes).

Four different bacteriostatic agents H2O2, NaClO, ClO2, and ozone water (O3) were used to the sterilization pretreatment of fresh muscle ofpenaeus vannamei. The bactericidal effect of these bacteriostatic agents were evaluated by aerobic bacterial count method, sensory evaluation and chromatic aberration analysis. The results showed that the optimum pretreatment concentrations of sterilization pretreatment by H2O2, NaClO, ClO2and ozone water (O3) were 3.0 g/kg, 50 mg/kg, 150 mg/kg and 1.0 mg/kg respectively. The optimum pretreatment time of sterilization pretreatment by H2O2, NaClO, ClO2and ozone water (O3) were 60 s, 300 s, 300 s and 300 s respectively. Furthermore, the bactericidal coefficients of sterilization pretreatment by H2O2, NaClO, ClO2and ozone water (O3) were 91.6%, 95.1%, 92.3% and 99.6% respectively. The effects of color and flavor of fresh muscle treated by these four bacteriostatic agents were compared. The results showed that the color and flavor of fresh muscle was less effected by ozone water (O3) method used for sterilization pretreatment method than other three methods. The total number of bacterial colony of sample treated 600 s by 1.0 mg/kg of ozone water (O3) method was reduced to 3.4 lgCFU/g, and the advantages of this method are significant sterilization effect as well as the low influences of color and sensory quality.

Myxobolus infection in koi fish allows followed by opportunistic microorganisms infection. Aeromonas hydrophila bacteria classified as opportunistic because it can cause illness in certain condition such as when environmental conditions change, stress and the condition of the host that has been infected by the parasite. This study purpose to determine the incidence rate Aeromonasis in koi (Cyprinus carpio carpio) infected Myxobolus koi at different degrees of infection. The results showed that of 120 samples taken, infected with M. koi in a mild degree of infection is 68.3%. Furthermore the medium infection is 22.5%, 1.7% severe infection and uninfected fish 7.5%. Each level of infection of M. koi taken samples for examination bacteria with skin samples and water. The results of bacterial examination showed that 17 positive samples of fish infected with A. hydrophila (85%) from 20 fish sample. 17 positive samples of fish infected with A. hydrophila consist of 3 sample normal fish, 7 sample M. koi mild infection, 6 sample M. koi medium infection and 1 sample severe infection. The results showed that the fish infected or not infected with M. koi, positive with A. hydrophila infection that needs to be done by using a bacterial colony calculation method of determining the Angka Lempeng Total (ALT) or Total Plate Count (TPC). The calculation results from the number of bacterial colony in various levels of infection of M. koi are sample 1 (normal koi fish) of 1.15 x108 CFU/ml, sample 2 (koi fish with a mild infection of M. koi) as much as 1.3 x108 CFU/ml. While the sample 3 (koi fish with a medium infection of M. koi) 2.02 x108 CFU/ml and sample 4 (with the severe infection of M. koi) 2.60 x108 CFU/ml.

biological procedures depend on an accurate count of the bacterial colonies and other organisms. In biomedical research and clinical diagnosis, there is a great need to quantify the amount of bacteria in the samples.This paper presents a simple and cost effective methodology for automatically counting the Bacterial Colonies (BC). The proposed methodology for automatic colony counter is based on digital image processing techniques. Proposed methodology is tested with different type of filter images. It is observed that the results obtained with the proposed counter were not significantly different from the manual counting.

Essential oils have a sedative effect on stress, and are also known to have antibiotic and anti-carcinogenic effects. These compounds have long been used as natural microbial agents, and have recently been added to a number of pharmaceutical, food and cosmetic products. Controlling the exposure to allergens and pathogens are important factors for the treatment of allergy, and potentially reducing the risk of sensitization and infection. Low humidity, at levels under 35%, may affect human comfort and health during the winter. Patients and other individuals require optimal humidification to maintain a moisturized respiratory tract necessary for protecting against bacterial infection. We designed an analytical system to examine the effects of aromatherapeutic essential oils on airborne bacteria. The antibacterial activities of essential oils were assayed using agar plate air-sampling methods. A bacterial suspension was sprayed into a bio-clean room through the upper holes using a spray gun. Free-floating airborne bacteria were collected from the bio-clean room (blank) in blood agar plates for 10 sec using an air sampler. Three different concentrations of essential oils (0.0005, 0.005 and 0.05 ppm) were then sprayed into the bio-clean room for 5 min. Free-floating airborne bacteria were collected every 10 min for 10 sec each. Treatment with 0.0005 ppm essential oils inhibited the growth of colonies; this effect appeared to persist after 60 min. Decreased bacterial colony growth was more apparent in the presence of 0.005 ppm and 0.05 ppm essential oils than 0.0005 ppm. These effects were observed after 60 min compared to the control (distilled water). These results indicate that essential oils are able to inhibit the growth of airborne bacteria.

Isolation of diphtheroids in human clinical specimens is not uncommon. Several studies have highlighted the significance of these bacteria in human infection, which morphologically resemble Corynebacterium diphtheriae. Previous studies have noted that occurrence of these bacteria in specimens like the blood should not be ignored as they can result in serious infections like endocarditis and sepsis among debilitated individuals, including the neonates. We report isolation of diphtheroid bacterium in blood from a case of septicaemia showing donut colony morphology.

Objective: To determine the effect of face washing with soap and water and cleaning with povidone iodine and cetrimide/chlorhexidine gluconate (Savlon) on upper-lid bacteria. Design: Prospective, nonrandomized clinical trial. Participants: Eighty patients attending the Eye Clinic, University College Hospital, Ibadan, Nigeria. Methods: Eighty patients assigned to 4 groups had swabs of the upper eyelid skin taken before and after face wash with soap and water, and cleansing with Savlon and 5% povidone iodine. Specimens were cultured and Gram stained. Bacterial counts were carried out using standard techniques. Results: Face washing with soap and water increased the proportion of patients with bacterial isolates from 80.0% to 87.5%. The average colony count increased from 187.1 to 318.5 colony units per mL ( p = 0.02). Application of 5% povidone iodine without face washing with soap and water reduced the proportion of patients with bacterial isolates from 82.6% (mean count 196.5) to 28.6% (mean count 34.1) ( p = 0.001); in comparison, the application of 5% povidone iodine after face washing with soap and water reduced the proportion from 71.4% (mean count 133.9) to 40.0% (mean count 69.0) ( p = 0.01). Application of Savlon without face washing with soap and water reduced the proportion of patients with bacterial isolates from 100% (mean count 3 10.9) to 41.2% (mean count 19.8) ( p = 0.004) compared with the application after face washing, which reduced the proportion from 89.5% (mean count 240.3) to 41.2% (mean count 82.9) ( p = 0.02). Conclusions: Both povidone and Savlon are effective in reducing periocular bacteria in an African setting. Prior face washing with soap and water had no added benefit in reducing bacterial colony count.

The cultivated area devoted to rice crops (Oryza sativa) in Brazil has expanded in recent years, along with improvements in yield. This has prompted the continuous exchange of material from active germplasm banks between government breeding programs. When placed in a greenhouse for multiplication purposes, rice accessions resulting from exchanges between USDA-ARS (United States Department of Agriculture - Agricultural Research Service) showed little or no germination. The accessions were sent to the tissue culture laboratory of BAG-CNPAF (Embrapa National Rice and Bean Research Center) to recover embryos by aseptically removing the seed coat of 10 seeds from each accession. Bacterial colony growth concomitant to germination inhibition was observed in some accessions, from which four bacterial isolates were obtained. Made available in DSpace on 2017-12-26T23:23:54Z (GMT). No. of bitstreams: 1 CNPAF2018pdv102n1.pdf: 213919 bytes, checksum: c3d290b54a0663e654d67513d579c97c (MD5) Previous issue date: 2017-12-18 Disease notes.

We introduce a cellular-automaton based model for the description of the migration and growth patterns of colonies of Bacillus subtilis. The two phases, associated with processes of migration and proliferation, are described by appropriate rules for the update of the automaton. We show that it is possible to reproduce the patterns present in the morphological diagram for B. subtilis and in particular the ring-like structure that the colonies adopt in the case of a not very hard medium and under nutrient abundance.

Bacteria, either indigenous or added, are immobilized in solid foods where they grow as colonies. Since the 80's, relatively few research groups have explored the implications of bacteria growing as colonies and mostly focused on pathogens in large colonies on agar/gelatine media. It is only recently that high resolution imaging techniques and biophysical characterization techniques increased the understanding of the growth of bacterial colonies, for different sizes of colonies, at the microscopic level and even down to the molecular level. This review covers the studies on bacterial colony growth in agar or gelatine media mimicking the food environment and in model cheese. The following conclusions have been brought to light. Firstly, under unfavorable conditions, mimicking food conditions, the immobilization of bacteria always constrains their growth in comparison with planktonic growth and increases the sensibility of bacteria to environmental stresses. Secondly, the spatial distribution describes both the distance between colonies and the size of the colonies as a function of the initial level of population. By studying the literature, we concluded that there systematically exists a threshold that distinguishes micro-colonies (radius < 100–200 μm) from macro-colonies (radius >200 μm). Micro-colonies growth resembles planktonic growth and no pH microgradients could be observed. Macro-colonies growth is slower than planktonic growth and pH microgradients could be observed in and around them due to diffusion limitations which occur around, but also inside the macro-colonies. Diffusion limitations of milk proteins have been demonstrated in a model cheese around and in the bacterial colonies. In conclusion, the impact of immobilization is predominant for macro-colonies in comparison with micro-colonies. However, the interaction between the colonies and the food matrix itself remains to be further investigated at the microscopic scale.

800x600 PENGARUH SARI BUAH NANAS ( Ananas comosus) DAN LAMA PENYIMPANAN TERHADAP JUMLAH KOLONI BAKTERI DAN KADAR PROTEIN IKAN BANDENG ( Chanos chanos ) SEBAGAI SUMBER BELAJAR DALAM PERENCANAAN PEMBELAJARAN BIOLOGI MATERI KINGDOM MONERA Qorry Aulya Rohmana 1 , Poncojari Wahyono 1 , Samsun Hadi 1 1 Pendidikan Biologi FKIP Universtias Muhammadiyah Malang, e-mail: aulyarohmana16@yahoo.com ABSTRACT The aims of this research is to know effect of any pineaple extract juice concentration and duration of saving and to determine concentration of the pineaple fruit extract juice and duration of saving which are the most optimal to the sum of bacterial colony and protein degree in bandeng fish. Research type used was True Experiment Design . A scheme used was Complete Random Scheme of factorial pattern. Data was as such the total of bacterial colony and protein contained in bandeng fish. Result of the research shows that concentration of pineaple fruit extract juise and duration of saving effect the bacterial colony total and protein containe in bandeng fish. The total of bacterial colony gets more as the duration of saving gets longer. As for protein contained in the bandeng fish gets lower as the saving duration goes. Key Words : Bandeng Fish, Pineaple, Number of Bacterial colony, Rate of Protein Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4

Predictive models are mathematical expressions that describe the growth, survival, inactivation, or biochemical processes of foodborne bacteria. During processing of contaminated raw materials and food preparation, bacteria are entrapped into the food residues, potentially transferred to the equipment surfaces (abiotic or inert surfaces) or cross-contaminate other foods (biotic surfaces). Growth of bacterial cells can either occur planktonically in liquid or immobilized as colonies. Colonies are on the surface or confined in the interior (submerged colonies) of structured foods. For low initial levels of bacterial population leading to large colonies, the immobilized growth differs from planktonic growth due to physical constrains and to diffusion limitations within the structured foods. Indeed, cells in colonies experience substrate starvation and/or stresses from the accumulation of toxic metabolites such as lactic acid. Furthermore, the micro-architecture of foods also influences the rate and extent of growth. The micro-architecture is determined by (i) the non-aqueous phase with the distribution and size of oil particles and the pore size of the network when proteins or gelling agent are solidified, and by (ii) the available aqueous phase within which bacteria may swarm or swim. As a consequence, the micro-environment of bacterial cells when they grow in colonies might greatly differs from that when they grow planktonically. The broth-based data used for modeling (lag time and generation time, the growth rate, and population level) are poorly transferable to solid foods. It may lead to an over-estimation or under-estimation of the predicted population compared to the observed population in food. If the growth prediction concerns pathogen bacteria, it is a major importance for the safety of foods to improve the knowledge on immobilized growth. In this review, the different types of models are presented taking into account the stochastic behavior of single cells in the growth of a bacterial population. Finally, the recent advances in the rules controlling different modes of growth, as well as the methodological approaches for monitoring and modeling such growth are detailed.

During cheese processing and ripening, bacteria develop as colonies. Substrates and metabolites must then diffuse either from or into the colonies. Exploring how the inner Q1 Q2 cells of the colony access the substrates or get rid of the products leads to study the Q7 Q8 diffusion of solutes inside bacterial colonies immobilized in cheese. Diffusion limitations of substrates within the bacterial colony could lead to starvation for the cells in the center of the colony. This study aimed at better understands ripening at the colony level, by investigating how diffusion phenomena inside colonies vary depending on both the physicochemical properties of the solutes and Lactococcus lactis strain. Dextrans (4, 70, and 155 kDa) and milk proteins (BSA, lactoferrin and aS1-casein) of different sizes and physicochemical properties were chosen as model of diffusing solutes, and two L. lactis strains presenting different surface properties were immobilized as colonies in a model cheese. Diffusion of solutes inside and around colonies was experimentally followed by time-lapse confocal microscopy. Dextran solutes diffused inside both lactococci colonies with a non-significantly different effective diffusion coefficient, which depended mainly on size of the solute. However, whereas flexible and neutral hydrophilic polymers such as dextran can diffuse inside colonies whatever its size, none of the three proteins investigated in this study could penetrate inside lactococci colonies. Therefore, the diffusion behavior of macromolecules through bacterial colonies immobilized in a model cheese did not only depends on the size of the diffusing solutes, but also and mainly on their physicochemical properties. Milk caseins are probably first hydrolyzed by the cell wall proteases of L. lactis and/or other proteases present in the cheese, and then the generated peptides diffuse inside colonies to be furthermetabolized into smaller peptides and amino acids by all the cells located inside the colonies.

An estimate of the distance between spots generated by a bacterial colony model is obtained. The model describes the morphogenesis of a spot pattern in colonies of chemotactic strains of Escherichia coli. Asymptotic methods for other cell-chemotaxis models, which have been successfully used by previous researchers, can be applied also to this model. However the calculations and the result is more complicated for this model. The result is verified by comparing it with the results by numerical computations of solutions of the model.

The formation of concentric ring-like colonies by bacterial species Bacillus subtilis has been investigated, focusing our attention on the effect of local cell density upon the bacterial motility: ...

A synthetic genetic circuit that mimics the quorum-sensing systems used by bacterial populations to coordinate gene expression enables bacteria to deliver drugs to mouse tumours in repeated and synchronized cycles. See Letter p.81 There is growing interest in using bacteria as living therapeutics, although the complications due to host responses and long-term effectiveness remain to be established. Omar Din et al. have now engineered a quorum-sensing clock into a strain of Salmonella known to target solid tumours by releasing a tumour-targeting toxin. The clock drives periodic lyses of the bacterial colony, thereby controlling the bacterial population and ensuring sustained anti-tumour toxin delivery in a mouse cancer model. Although the system as it stands does not represent an effective cure, this work indicates that synthetic biology can be harnessed to achieve dynamic and sustained delivery of therapeutics in vivo.

Despite a number of different numerical techniques existing for modeling the uptake of the nutrients, metabolism, maintenance, cell division and growth of bacteria population, none of them can be treated as a universally one. In this new model we have combined two techniques. The first one — agent-based — has been used for modeling the behavior of an individual bacterium. The agent objects (AOs) define generic features of the bacterium and the ways they interact with the environment and with the neighboring bacteria. The cellular automata are used for modeling the bacterial environment and represent communication layer for the agents, while a fixed two-dimensional grid defines the living space. The growth of the bacterial colony depends on the amount of free space in the closest neighborhood of individuals, which is required for reproduction, and on the availability of nutrients. We have matched the parameters of the model to demonstrate various growth structures developed by bacteria populations. We show that the patterns generated by the bacteria due to their collective behavior reflect the dynamical vitality of population and its fitness factor. We observe that the strongest populations self-organize in rod-like structures, which are reproduced in experimental microscopy images characteristic for bioflims and anthrax bacterial colonies.

The purpose of this preliminary study is to evaluate the effect of various wavelengths of light on nanobacteria (NB).NB and mitochondria use light for biological processes. NB have been described as multifunctional primordial nanovesicles with the potential to utilize solar energy for replication. NB produce slime, a process common to living bacteria. Slime release is an evolutionary important stress-dependent phenomenon increasing the survival chance of individual bacteria in a colony. In the cardiovascular system, stress-induced bacterial colony formation may lead to a deposition of plaque.Cultured NB were irradiated with NASA-LEDs at different wavelengths of light: 670, 728 and 880 nm. Light intensities were about 500k Wm(-2), and energy density was 1 x 10(4) J m(-2).Monochromatic light clearly affected replication of NB. Maximum replication was achieved at 670 nm.The results indicate that suitable wavelengths of light could be instrumental in elevating the vitality level of NB, preventing the production of NB-mediated slime, and simultaneously increasing the vitality level of mitochondria. The finding could stimulate the design of cooperative therapy concepts that could reduce death caused by myocardial infarcts.

We have developed a method for fabricating bacterial colony arrays and complex patterns using commercially available ink-jet printers. Bacterial colony arrays with a density of 100 colonies/cm(2) were obtained by directly ejecting Escherichia coli (E. coli) onto agar-coated substrates at a rapid arraying speed of 880 spots per second. Adjusting the concentration of bacterial suspensions allowed single colonies of viable bacteria to be obtained. In addition, complex patterns of viable bacteria as well as bacteria density gradients were constructed using desktop printers controlled by a simple software program.

Spatio-temporal patterns emerged inside a colony of bacterial species Proteus mirabilis on the surface of nutrient-rich semisolid agar medium have been investigated. We observed various patterns composed of the following basic types: propagating stripe, propagating stripe with fixed dislocation, expanding and shrinking target, and rotating spiral. The remarkable point is that the pattern changes immediately when we alter the position for observation, but it returns to the original if we restore the observing position within a few minutes. We further investigated mesoscopic and microscopic properties of the spatio-temporal patterns. It turned out that whenever the spatio-temporal patterns are observed in a colony, the areas are composed of two superimposed monolayers of elongated bacterial cells. In each area they are aligned almost parallel with each other like a two-dimensional nematic liquid crystal, and move collectively and independently of another layer. It has been found that the observed spatio-tem...

Objectives: This study aimed to analyze the effects of propolis extract and propolis candies on Streptococcus sanguinis. Methods: Bacterial suspensions were exposed to propolis extract and propolis candies. For propolis extract, a minimum inhibitory concentration(MIC) was determined using a spectrophotometer, and a minimum bactericidal concentration (MBC) was determined using a standard plate count method. Samples were cultured in brain heart infusion agar, incubated for 24 hrs, and the bacterial colony units formed on the agar plates were manually counted. Results: Propolis extract inhibits the growth of S. sanguinis at MIC 5% and MBC 10%. The colonies of S. sanguinis decreased after exposure to propolis candies. Conclusions: Propolis extract and propolis candies are effective to inhibit the growth of S. sanguinis .

We have investigated the periodic colony growth of bacterial species Bacillus subtilis . A colony grows cyclically with the interface repeating an advance (migration phase) and a rest (consolidatio...

To evaluate the integrity of the human milk (pH, bacterial counts, host defense factors and nutrients) subjected to thawing, warming, refrigeration and maintenance at room temperature. Mothers in the neonatal intensive care unit donated freshly expressed milk. A baseline sample was stored at −80 °C and the remainder of the milk was divided and stored for 7 days at −20 °C. The milk was then subjected to two methods of thawing and warming: tepid water and waterless warmer. Thawed milk also was refrigerated for 24 h prior to warming. Lastly, warmed milk was maintained at room temperature for 4 h to simulate a feeding session. Samples were analyzed for pH, bacterial colony counts, total fat and free fatty acids, and the content of protein, secretory IgA and lactoferrin. Data were analyzed by repeated-measures analysis of variance and paired t test. There were no differences between processing methods and no changes in fat, protein, lactoferrin and secretory immunoglobulin A with processing steps. Milk pH and bacterial colony counts declined while free fatty acids rose with processing. Refrigeration of thawed milk resulted in greater declines in pH and bacteria and increases in free fatty acids. Bacterial colony counts and free fatty acids increased with maintenance at room temperature. The integrity of the milk was affected similarly by the two thawing and warming methods. Thawing and warming change the integrity of previously frozen human milk, but not adversely. Concerns about maintaining warmed milk at room temperature need to be explored.

In this chapter, we present a set of algorithms that are inspired by the different bacteria behavioural patterns, i.e., bacterial foraging algorithm (BFA), bacterial colony chemotaxis (BCC) algorithm, superbug algorithm (SuA), bacterial colony optimization (BCO) algorithm, and viral system (VS) algorithm. We first describe the general knowledge of bacteria foraging behaviour in Sect. 2.1. Then, the fundamentals and performances of BFA, BCC algorithm, SuA, BCO algorithm, and VS algorithm are introduced in Sects. 2.2 and 2.3, respectively. Finally, Sect. 2.4 summarises this chapter.

It is well known from experiments that bacterial species Bacillus subtilis exhibit various colony patterns. These are essentially classified into five types in the morphological diagram, depending on the substrate softness and nutrient concentration. (A) diffusion-limited aggregation-like; (B) Eden-like; (C) concentric ring-like; (D) disk-like; and (E) dense branching morphology-like. There arises the naive question of whether the diversity of colony patterns observed in experiments is caused by different effects or governed by the same underlying principles. Our research has led us to propose reaction–diffusion models to describe the morphological diversity of colony patterns except for Eden-like ones.

We have investigated experimentally the pattern formation of bacterial colonies. We have especially examined DBM (dense-branching-morphology)-like colonies of bacterial species Bacillus subtilis . It was found from microscopic observations that many active bacterial cells collect and make a group on the tip of each growing branch. Branches repel each other and split sometimes as they grow outward. It was confirmed macroscopically that both averaged branch width and averaged branch gap decrease systematically when increasing the nutrient concentration C n , while their ratio remains unchanged with the approximate value of one. It was also found that the distribution of branch lengths is very close to exponential, suggesting that the tip-splitting of branches takes place at random.

Many bacteriologic studies, including cellular invasion and adherence assays, require enumeration of viable organisms or colony forming units. When attempting to screen large numbers of clinical or environmental isolates or laboratory-derived mutants for differences in invasion or adherence phenotype, standard plating methods can be cumbersome and severely limit the number of organisms or conditions which can be tested. As a potential alternative, we describe a simple, rapid and inexpensive soft agar-based technique for semi-quantitative determination of bacterial colony counts directly within the wells of a 96-well microtiter plate.

Bacterial colony counts in reusable water reservoirs in a humidified oxygen supply system maintained only by the addition of nonsterilized water, with or without washing (conventional procedure), were examined. Bacteria were detected in all the reservoirs even before the operation of the oxygen suppliers, and colony counts of more than 1 x 10(2)/ml of bacteria were detected in some reservoirs without washing. Many bacteria were also detected in many reservoirs, after the operation of the oxygen suppliers, indicating that bacteria had contaminated the water reservoirs and propagated during this operation. These results suggest that it is not recommended to maintain these water reservoirs by the conventional procedure.

The Artificial Reaction Network (ARN) is an Artificial Chemistry representation inspired by cell signaling networks. The ARN has previously been applied to the simulation of the chemotaxis pathway of Escherichia coli and to the control of limbed robots. In this paper we discuss the design of an ARN control system composed of a combination of network motifs found in actual biochemical networks. Using this control system we create multiple cell-like autonomous agents capable of coordinating all aspects of their behavior, recognizing environmental patterns and communicating with other agent's stigmergically. The agents are applied to simulate two phases of the life cycle of Dictyostelium discoideum: vegetative and aggregation phase including the transition. The results of the simulation show that the ARN is well suited for construction of biochemical regulatory networks. Furthermore, it is a powerful tool for modeling multi agent systems such as a population of amoebae or bacterial colony.

Invasion of the culture medium is a feature frequently studied in yeasts, in which it has been related to a greater virulence, but it is practically unknown in bacteria. Recently, it has been demonstrated that several clinically relevant bacterial species were also able of invading agar media, so it was necessary to design a microbiological assay to study the expression of this character in bacteria. Accordingly, a bacterial agar invasion test based on colony/biofilm development was designed, which allows qualitative and quantitative characterization of bacterial growth into the agar culture medium. Once the culture conditions were optimized, the test was applied to 90 strains from nine bacterial species, validating its usefulness for differentiating invasive strains (positive) from those non invasive (negative). The test also allows sorting invasive strains according to agar invasion intensity (low, moderate, high) and topographic invasion pattern (peripheral, homogeneous, mixed). Moreover, an image analysis routine to quantify the invasion was developed. Implemented method enables direct measuring of two invasion parameters (invasion area and number of invasion dots), automated calculation of three relative variables (invasion relative area, invasion dots relative density, and invasion dot average area), and the establishment of strain specific frequency histograms. This new methodology is simple, fast, reproducible, objective, inexpensive and can be used to study a great number of specimens simultaneously, all of which make it suitable for incorporation to the routine of any microbiology laboratory. It could also be a useful tool for additional studies related to clinical aspects of bacterial isolates such as virulence and antimicrobial response.

Matrix assisted laser desorption ionization time of flight mass spectrometry has been explored as a tool to bacterial colony morphotyping.To this end,four colony morphotypes of Pseudomonas aeruginosa and four of Staphylococcus aureus were analysed using intact bacteria.Results suggest that mass spectrometry of intact bacteria could,in some extent,be used to complement the classical morphological classification of bacteria., Financial support from IBB-CEB and Fundacao para a Ciencia e Tecnologia (FCT) and European Community fund FEDER, through Program COMPETE, in the ambit of the FCT project "PTDC/SAU-SAP/113196/2009/ FCOMP-01-0124-FEDER-016012" and Ana Margarida Sousa PhD grant (SFRH/BD/72551/2010), is gratefully acknowledged. Authors also thank Portugal-Spain cooperation action sponsored by the Foundation of Portuguese Universities [E 48/11] and the Spanish Ministry of Science and Innovation [AIB2010PT-00353].