Search results for: Pathogenic microbes
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 84

Search results for: Pathogenic microbes

54 The Integrated Studies of Infectious Disease Using Mathematical Modeling and Computer Simulation

Authors: R. Kongnuy, E. Naowanich

Abstract:

In this paper we develop and analyze the model for the spread of Leptospirosis by age group in Thailand, between 1997 and 2010 by using mathematical modeling and computer simulation. Leptospirosis is caused by pathogenic spirochetes of the genus Leptospira. It is a zoonotic disease of global importance and an emerging health problem in Thailand. In Thailand, leptospirosis is a reportable disease, the top three age groups are 23.31% in 35-44 years olds group, 22.76% in 25-34 year olds group, 17.60% in 45-54 year olds group from reported leptospirosis between 1997 and 2010, with a peak in 35-44 year olds group. Our paper, the Leptosipirosis transmission by age group in Thailand is studied on the mathematical model. Some analytical and simulation results are presented.

Keywords: Age Group, Equilibrium State, Leptospirosis, Mathematical Modeling.

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53 A Review on Application of Chitosan as a Natural Antimicrobial

Authors: F. Nejati Hafdani, N. Sadeghinia

Abstract:

In recent years application of natural antimicrobials instead of conventional ones, due to their hazardous effects on health, has got serious attentions. On the basis of the results of different studies, chitosan, a natural bio-degradable and non-toxic biopolysaccharide derived from chitin, has potential to be used as a natural antimicrobial. Chitosan has exhibited high antimicrobial activity against a wide variety of pathogenic and spoilage microorganisms, including fungi, and Gram-positive and Gramnegative bacteria. The antimicrobial action is influenced by intrinsic factors such as the type of chitosan, the degree of chitosan polymerization and extrinsic factors such as the microbial organism, the environmental conditions and presence of the other components. The use of chitosan in food systems should be based on sufficient knowledge of the complex mechanisms of its antimicrobial mode of action. In this article we review a number of studies on the investigation of chitosan antimicrobial properties and application of them in culture and food mediums.

Keywords: Antimicrobial, Chitosan, Preservative

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52 Safety Assessment of Traditional Ready-to-Eat Meat Products Vended at Retail Outlets in Kebbi and Sokoto States, Nigeria

Authors: M. I. Ribah, M. Jibir, Y. A. Bashar, S. S. Manga

Abstract:

Food safety is a significant and growing public health problem in the world and Nigeria as a developing country, since food-borne diseases are important contributors to the huge burden of sickness and death of humans. In Nigeria, traditional ready-to-eat meat products (RTE-MPs) like balangu, tsire, guru and dried meat products like kilishi, dambun nama, banda, were reported to be highly appreciated because of their eating qualities. The consumption of these products was considered as safe due to the treatments that are usually involved during their production process. However, during processing and handling, the products could be contaminated by pathogens that could cause food poisoning. Therefore, a hazard identification for pathogenic bacteria on some traditional RTE-MPs was conducted in Kebbi and Sokoto States, Nigeria. A total of 116 RTE-MPs (balangu-38, kilishi-39 and tsire-39) samples were obtained from retail outlets and analyzed using standard cultural microbiological procedures in general and selective enrichment media to isolate the target pathogens. A six-fold serial dilution was prepared and using the pour plating method, colonies were counted. Serial dilutions were selected based on the prepared pre-labeled Petri dishes for each sample. A volume of 10-12 ml of molten Nutrient agar cooled to 42-45°C was poured into each Petri dish and 1 ml each from dilutions of 102, 104 and 106 for every sample was respectively poured on a pre-labeled Petri plate after which colonies were counted. The isolated pathogens were identified and confirmed after series of biochemical tests. Frequencies and percentages were used to describe the presence of pathogens. The General Linear Model was used to analyze data on pathogen presence according to RTE-MPs and means were separated using the Tukey test at 0.05 confidence level. Of the 116 RTE-MPs samples collected, 35 (30.17%) samples were found to be contaminated with some tested pathogens. Prevalence results showed that Escherichia coli, salmonella and Staphylococcus aureus were present in the samples. Mean total bacterial count was 23.82×106 cfu/g. The frequency of individual pathogens isolated was; Staphylococcus aureus 18 (15.51%), Escherichia coli 12 (10.34%) and Salmonella 5 (4.31%). Also, among the RTE-MPs tested, the total bacterial counts were found to differ significantly (P < 0.05), with 1.81, 2.41 and 2.9×104 cfu/g for tsire, kilishi, and balangu, respectively. The study concluded that the presence of pathogenic bacteria in balangu could pose grave health risks to consumers, and hence, recommended good manufacturing practices in the production of balangu to improve the products’ safety.

Keywords: Ready-to-eat meat products, retail outlets, safety assessment, public health.

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51 The Occurrence of Fungi in Activated Sludge from MBRs

Authors: Mohamed F. Awad, M. Kraume

Abstract:

The objective of this study is to evaluate the occurrence of fungi in aerobic and anoxic activated sludge from membrane bioreactors (MBRs). Thirty-six samples of both aerobic and anoxic activated sludge were taken from 2 MBR treating domestic wastewater. Over a period of eight months 2 samples from each plant were taken per month. The samples were prepared for count and definition of fungi. The obtained data show that, sixty species belonging to 27 genera were collected from activated sludge samples under aerobic and anoxic conditions. Regarding to the fungi definition, under aerobic condition the Geotrichum was found at (8.8%) followed by Penicillium (75.0%), Yeasts (65.7%) and Trichoderma (55.5%), while Yeasts (77.1%) Geotrichum candidumand Penicillium (61.1%) species were the most prevalent in anoxic activated sludge. The results indicate that activated sludge is habitat for growth and sporulation of different groups of fungi, both saprophytic and pathogenic.

Keywords: Aerobic conditions, Anoxic conditions, Activated sludge, Membrane bioreactor, Fungi.

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50 Effects and Mechanization of a High Gradient Magnetic Separation Process for Particulate and Microbe Removal from Ballast Water

Authors: Zhijun Ren, Zhang Lin, Zhao Ye, Zuo Xiangyu, Mei Dongxing

Abstract:

As a pretreatment process of ballast water treatment, the performance of high gradient magnetic separation (HGMS) technology for the removal of particulates and microorganisms was studied. The results showed that HGMS process could effectively remove suspended particles larger than 5 µm and had ability to resist impact load. Microorganism could also be effectively removed by HGMS process, and the removal effect increased with increasing magnetic field strength. The maximum removal rates for Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) were 4016.1% and 9675.3% higher, respectively, than without the magnetic field. In addition, the superoxide dismutase (SOD) activity of the microbes decreased by 32.2% when the magnetic field strength was 15.4 mT for 72 min. The microstructure of the stainless steel wool was investigated, and the results showed that particle removal by HGMS has common function by the magnetic force of the high-strength, high-gradient magnetic field on weakly magnetic particles in the water, and on the stainless steel wool.

Keywords: HGMS, particulates, superoxide dismutase activity, steel wool magnetic medium.

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49 Mercury Removal Using Pseudomonas putida (ATTC 49128): Effect of Acclimatization Time, Speed and Temperature of Incubator Shaker

Authors: A. A. M. Azoddein, R. M. Yunus, N. M. Sulaiman, A. B. Bustary, K. Sabar

Abstract:

Microbes have been used to solve environmental problems for many years. The role of microorganism to sequester, precipitate or alter the oxidation state of various heavy metals has been extensively studied. Treatment using microorganism interacts with toxic metal are very diverse. The purpose of this research is to remove the mercury using Pseudomonas putida (P. putida), pure culture ATTC 49128 at optimum growth parameters such as techniques of culture, acclimatization time and speed of incubator shaker. Thus, in this study, the optimum growth parameters of P. putida were obtained to achieve the maximum of mercury removal. Based on the optimum parameters of P. putida for specific growth rate, the removal of two different mercury concentration, 1 ppm and 4 ppm were studied. From mercury nitrate solution, a mercuryresistant bacterial strain which is able to reduce from ionic mercury to metallic mercury was used to reduce ionic mercury. The overall levels of mercury removal in this study were between 80% and 89%. The information obtained in this study is of fundamental for understanding of the survival of P. putida ATTC 49128 in mercury solution. Thus, microbial mercury removal is a potential bioremediation for wastewater especially in petrochemical industries in Malaysia.

Keywords: Pseudomonas putida, growth kinetic, biosorption, mercury, petrochemical wastewater.

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48 Regulatory Effects of Carbon Sources on Tabtoxin Production (A β-lactam Phytotoxin of Pseudomonas syringae pv. tabaci)

Authors: N. Messaadia, D. Harzallah

Abstract:

The effects of divers carbon substrates were investigated for the tabtoxin production of an isolated pathogenic Pseudomonas syringae pv. tabaci, the causal agent of wildfire of tobacco and are discussed in relation to the bacterium growth. The isolated organism was grown in batch culture on Woolley's medium (28°C, 200 rpm, during 5 days). The growth has been measured by the optical density (OD) at 620 nm and the tabtoxin production quantified by Escherichia coli (K-12) bioassay technique. The growth and the tabtoxin production were both influenced by the substrates (sugars, amino acids, organic acids) used, each, as a sole carbon source and as a supplement for the same amino acids. The most significant quantities of tabtoxin were obtained in presence of some amino acids used as sole carbon source and/or as supplement.

Keywords: Amino acid supplement, carbon substrates, batch culture, Pseudomonas syringae pv. tabaci.

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47 Mycoflora of Activated Sludge with MBRs in Berlin, Germany

Authors: Mohamed F. Awad, M. Kraume

Abstract:

Thirty six samples from each (aerobic and anoxic) activated sludge were collected from two wastewater treatment plants with MBRs in Berlin, Germany. The samples were prepared for count and definition of fungal isolates; these isolates were purified by conventional techniques and identified by microscopic examination. Sixty tow species belonging to 28 genera were isolated from activated sludge samples under aerobic conditions (28 genera and 58 species) and anoxic conditions (26 genera and 52 species). The obtained data show that, Aspergillus was found at 94.4% followed by Penicillium 61.1 %, Fusarium (61.1 %), Trichoderma (44.4 %) and Geotrichum candidum (41.6 %) species were the most prevalent in all activated sludge samples. The study confirmed that fungi can thrive in activated sludge and sporulation, but isolated in different numbers depending on the effect of aeration system. Some fungal species in our study are saprophytic, and other a pathogenic to plants and animals.

Keywords: Activated sludge, membrane bioreactors, aerobic, anoxic conditions, fungi

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46 Fungal Disinfection by Nanofiltration in Tomato Soilless Culture

Authors: R. Amooaghaie

Abstract:

Principally, plants grown in soilless culture may be attacked by the same pests and diseases as cultivated traditionally in soil. The most destructive phytopathogens are fungi, such as Phythium, Phytophthora and Fusarium, followed by viruses, bacteria and nematodes. We investigated effect of carbon nanotube filters on disease management of soilless culture. Tomato seedlings transplant in plastic pots filled with a soilless media of vermiculite. The crop irrigated and fertilized using a hydroponic nutrient solution. We used carbon nanotube filters for nutrient solution disinfection. Our results show that carbon nanotube filtration significantly reduces pathogens on tomato plants. Fungal elimination (Fusarium oxysporum and Pythium spp.) was usually successful at about 96 to 99.9% all over the cultural season. It is seem that in tomato soilless culture, nanofiltration constitutes a reliable method that allows control of the development of diseases caused by pathogenic fungi

Keywords: Fusarium oxysporum, Nanofilteration, Pythium spp., Soilless culture, Tomato

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45 Effects of Mobile Phone Generated High Frequency Electromagnetic Field on the Viability and Biofilm Formation of Staphylococcus aureus

Authors: Zaini Mohd-Zain, Mohd-Saufee A.F. Mohd-Ismail, Norlida Buniyamin

Abstract:

Staphylococcus aureus, one of the microflora in a human external auditory canal (EAC) is frequently exposed to highfrequency electromagnetic field (HF-EMF) generated by mobile phones. It is normally non-pathogenic but in certain circumstances, it can cause infections. This study investigates the changes in the physiology of S. aureus when exposed to HF-EMF of a mobile phone. Exponentially grown S. aureus were exposed to two conditions of EMF irradiation (standby-mode and on-call mode) at four durations; 15, 30, 45 and 60 min. Changes in the viability and biofilm production of the S. aureus were compared between the two conditions of exposure. EMF from the standby-mode has enhanced the growth of S. aureus but during on-call, the growth was suppressed. No significant difference in the amount of biofilm produced in both modes of exposure was observed. Thus, HF-EMF of mobile phone affects the viability of S. aureus but not its ability to produce biofilm.

Keywords: Electromagnetic field, mobile phone, biofilm, Staphylococcus aureus

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44 Inhibitory Effect of Helichrysum arenarium Essential Oil on the Growth of Food Contaminated Microorganisms

Authors: Ali Mohamadi Sani

Abstract:

The aim of this study was to determine the antimicrobial effect of Helichrysum arenarium L. essential oil in "in-vitro" condition on the growth of seven microbial species including Bacillus subtilis, Escherichia coli, Staphylococcus aureus, Saccharomyces cereviciae, Candida albicans, Aspergillus flavus and Aspergillus parasiticus using micro-dilution method. The minimum inhibitory concentration (MIC) and minimum bactericidal or fungicidal concentration (MBC, MFC) were determined for the essential oil at ten concentrations. Finally, the sensitivity of tested microbes to essential oil of H. arenarium was investigated. Results showed that Bacillus subtilis (MIC=781.25 and MBC=6250 µg/ml) was more resistance than two other bacterial species. Among the tested yeasts, Saccharomyces cereviciae (MIC=97.65 and MFC=781.25 µg/ml) was more sensitive than Candida albicans while among the fungal species, growth of Aspergillus parasiticus inhibited at lower concentration of oil than the Aspergillus flavus. The extracted essential oil exhibited the same MIC value in the liquid medium against all fungal strains (48.82 µg/ml), while different activity against A. flavus and A. parasiticus was observed in this medium with MFC values of 6250 and 390.625µg/ml, respectively. The results of the present study indicated that Helichrysum arenarium L essential oil had significant (P<0.05) antimicrobial activity; therefore, it can be used as a natural preservation to increase the shelf life of food products.

 

Keywords: Helichrysum arenarium, Antimicrobial agent, Essential oil, MIC.

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43 Aflatoxins Aggravate the Incidence of Salmonellosis Outbreak in Fattening Calves: A Case Study

Authors: Abdel-Rahman A., El Okle O. S.

Abstract:

Fever, bloody diarrhea and high mortality rate were the main clinical finding in a group of fattening calves. Analysis of corn silage revealed presence of aflatoxins at level of 370 ppb. This level of aflatoxins in the feed of cattle is somewhat low to be the main cause of reported signs. Leukocytopenia, anemia, decreased lymphocytic activity and lowered phagocytic index are the main hematological and immunological alterations in diseased calves. Bacteriological investigation revealed isolation of pathogenic Salmonella typhimurium from the rectal swabs of diseased calves. Our results suggested that, long duration of exposure to aflatoxins even at small concentrations may considered as predisposing factor for the incidence of natural infectious outbreaks as salmonellosis due to its immunosuppressive effect. We can conclude that the veterinarians and owners must be given an attention to the relation between aflatoxicosis and salmonellosis under field condition. We are recommended that the treatment program during similar outbreaks must be including anti-aflatoxins preparations beside the antimicrobial therapy.

Keywords: Aflatoxins, Calves, Salmonellosis.

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42 Microbiological Analysis, Cytotoxic and Genotoxic Effects from Material Captured in PM2.5 and PM10 Filters Used in the Aburrá Valley Air Quality Monitoring Network (Colombia)

Authors: Carmen E. Zapata, Juan Bautista, Olga Montoya, Claudia Moreno, Marisol Suarez, Alejandra Betancur, Duvan Nanclares, Natalia A. Cano

Abstract:

This study aims to evaluate the diversity of microorganisms in filters PM2.5 and PM10; and determine the genotoxic and cytotoxic activity of the complex mixture present in PM2.5 filters used in the Aburrá Valley Air Quality Monitoring Network (Colombia). The research results indicate that particulate matter PM2.5 of different monitoring stations are bacteria; however, this study of detection of bacteria and their phylogenetic relationship is not complete evidence to connect the microorganisms with pathogenic or degrading activities of compounds present in the air. Additionally, it was demonstrated the damage induced by the particulate material in the cell membrane, lysosomal and endosomal membrane and in the mitochondrial metabolism; this damage was independent of the PM2.5 concentrations in almost all the cases.

Keywords: Cytotoxic, genotoxic, microbiological analysis, PM10, PM2.5.

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41 Evaluation of Bacterial Composition of the Aerosol of Selected Abattoirs in Akure, South Western Nigeria

Authors: Funmilola O. Omoya, Joseph O. Obameso, Titus A. Olukibiti

Abstract:

This study was carried out to reveal the bacterial composition of aerosol in the studied abattoirs. Bacteria isolated were characterized according to microbiological standards. Factors such as temperature and distance were considered as variable in this study. The isolation was carried out at different temperatures such as 27oC, 31oC and 29oC and at various distances of 100meters and 200meters away from the slaughter sites. Result obtained showed that strains of Staphylococcus aureus, Escherichia coli, Bacillus subtilis, Lactobacillus alimentarius and Micrococcus sp. were identified. The total viable counts showed that more microorganisms were present in the morning while the least viable count of 388cfu was recorded in the evening period of this study. This study also showed that more microbial loads were recorded the further the distance is to the slaughter site. Conclusively, the array of bacteria isolated suggests that abattoir sites may be a potential source of pathogenic organisms to commuters if located within residential environment.

Keywords: Abattoir, Aerosol, Bacterial Composition, Environment.

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40 Antimicrobial Potentials of Flavonoids Isolated from Tagetes erecta

Authors: N. Behidj-Benyounes, S. Bennaamane, F. Zohra Bissaad, N. Chebouti, H. Mohandkaci, N. Abdalaziz, S. Iddou

Abstract:

In this study, we are interested in a species of the family of Asteraceae (Tagetes erecta). This family is considered as a source of antimicrobial extracts with strong capacity. The extraction of the flavonoids is carried out by the method of liquid/liquid with the use of successive solvents. Afterwards, we evaluated the biological activity of the flavonoids on five pathogenic bacterial stocks such as Escherichia coli, Bacillus subtilis, Klebsiella pneumoniae, Pseudomonas aeruginosa and Staphylococcus aureus and two stocks of yeasts to knowing Candida albicans) and Saccharomyces cerevisiae, by employing the method of the aromatogramme starting from a solid disc. The result of the antimicrobial activity shows an action and a variable degree of sensitivity according to bacterial stocks tested. It will be noted that the flavonoids have an inhibiting effect on E. coli, B. subtilis, K. pneumoniae and S. aureus. But a resistance with respect to the extract by P. aeruginosa, C. albicans and S. cerevisiae is to be mentioned.

Keywords: Antimicrobial activity, flavonoids, microbial strains, Tagetes erecta L.

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39 Efficacy and Stability of Ceramic Powder to Inactivate Avian Influenza Virus

Authors: Chanathip Thammakarn, Misato Tsujimura, Keisuke Satoh, Tomomi Hasegawa, Miho Tamura, Akinobu Kawamura, Yuki Ishida, Atsushi Suguro, Hakimullah Hakim, Sakchai Ruenphet, , Kazuaki Takehara

Abstract:

This experiment aims to demonstrate the efficacy of ceramic powder derived from various sources to inactivate avian influenza virus and its possibility to use in the environment. The ceramics used in the present experiment were derived from chicken feces (CF), scallop shell (SS), polyvinyl chloride (PVC) and soybean (SB). All ceramics were mixed with low pathogenic AIV (LPAIV) H7N1, and then kept at room temperature. The recovered virus was titrated onto Madin-Darby canine kidney (MDCK) cells. All ceramics were assessed the inactivation stability in the environment by keeping under sunlight and under wet-dry condition until reached 7 week or 7 resuspension times respectively. The results indicate that all ceramics have excellent efficacy to inactivate LPAIV. This efficacy can be maintained under the simulated condition. The ceramics are expected to be the good materials for application in the biosecurity system at farms.

Keywords: Avian Influenza, Ceramics, Efficacy, Stability.

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38 Effect of Entomopathogenic Fungi on the Food Consumption of Acrididae Species

Authors: S. Kumar, R. Sultana

Abstract:

This study was conducted to evaluate the effect of Aspergillus species on acridid populations which are major agricultural pests of rice, sugarcane, wheat, maize and fodder crops in Pakistan. Three and replicates i.e. Aspergillus flavus, A. fumigatus and A. niger, excluding the control, were held under laboratory conditions. It was observed that consumption faecal production of acridids was significantly reduced after the pathogenic application of Aspergillus. In the control replicate, the mortality ratio for stage (N4-N6) was maximum on day 2nd i.e. [F10.7 = 18.33, P < 0.05] followed by [F4.20 = 07.85, P < 0.05] and [F3.77 = 06.11, P < 0.05] on 4th and 3rd day, respectively. Similarly, it was a minimum i.e. [F0.48 = 84.65, P < 0.05] on the 1st day. It was also noted that faecal production of Acridid nymphs was not significantly affected when treated with conidial concentration in H2O formulation; however, it was significantly reduced after the contamination with conidial concentration in oil. The high morality of acridids after contamination of Aspergillus supports their use as bio-control agent for reducing pest population. The present study recommends that exploration and screening must be conducted to provide additional pathogens for evaluation as potential biological control against grasshoppers and locusts.

Keywords: Acridid, agriculture, Aspergillus, formulation, Grasshoppers.

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37 Soil Compaction in Tropical Organic Farming Systems and Its Impact on Natural Soil-Borne Disease Suppression: Challenges for Management

Authors: Ishak, L., McHenry, M. T., Brown, P. H.

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Organic farming systems still depend on intensive, mechanical soil tillage. Frequent passes by machinery traffic cause substantial soil compaction that threatens soil health. Adopting practices as reduced tillage and organic matter retention on the soil surface are considered effective ways to control soil compaction. In tropical regions, however, the acceleration of soil organic matter decomposition and soil carbon turnover on the topsoil layer is influenced more rapidly by the oscillation process of drying and wetting. It is hypothesized therefore, that rapid reduction in soil organic matter hastens the potential for compaction to occur in organic farming systems. Compaction changes soil physical properties and as a consequence it has been implicated as a causal agent in the inhibition of natural disease suppression in soils. Here we describe relationships between soil management in organic vegetable systems, soil compaction, and declining soil capacity to suppress pathogenic microorganisms.

Keywords: Organic farming systems, soil compaction, soil disease suppression, tropical regions.

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36 Stochastic Modeling and Combined Spatial Pattern Analysis of Epidemic Spreading

Authors: S. Chadsuthi, W. Triampo, C. Modchang, P. Kanthang, D. Triampo, N. Nuttavut

Abstract:

We present analysis of spatial patterns of generic disease spread simulated by a stochastic long-range correlation SIR model, where individuals can be infected at long distance in a power law distribution. We integrated various tools, namely perimeter, circularity, fractal dimension, and aggregation index to characterize and investigate spatial pattern formations. Our primary goal was to understand for a given model of interest which tool has an advantage over the other and to what extent. We found that perimeter and circularity give information only for a case of strong correlation– while the fractal dimension and aggregation index exhibit the growth rule of pattern formation, depending on the degree of the correlation exponent (β). The aggregation index method used as an alternative method to describe the degree of pathogenic ratio (α). This study may provide a useful approach to characterize and analyze the pattern formation of epidemic spreading

Keywords: spatial pattern epidemics, aggregation index, fractaldimension, stochastic, long-rang epidemics

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35 Starch Based Biofilms for Green Packaging

Authors: Roshafima R. Ali, W. A. Wan Abdul Rahman, Rafiziana M. Kasmani, N. Ibrahim

Abstract:

This current research focused on development of degradable starch based packaging film with enhanced mechanical properties. A series of low density polyethylene (LDPE)/tapioca starch compounds with various tapioca starch contents were prepared by twin screw extrusion with the addition of maleic anhydride grafted polyethylene as compatibilizer. Palm cooking oil was used as processing aid to ease the blown film process, thus, degradable film can be processed via conventional blown film machine. Studies on their characteristics, mechanical properties and biodegradation were carried out by Fourier Transform Infrared (FTIR) spectroscopy and optical properties, tensile test and exposure to fungi environment respectively. The presence of high starch contents had an adverse effect on the tensile properties of LDPE/tapioca starch blends. However, the addition of compatibilizer to the blends improved the interfacial adhesion between the two materials, hence, improved the tensile properties of the films. High content of starch amount also was found to increase the rate of biodegradability of LDPE/tapioca starch films. It can be proved by exposure of the film to fungi environment. A growth of microbes colony can be seen on the surface of LDPE/tapioca starch film indicates that the granular starch present on the surface of the polymer film is attacked by microorganisms, until most of it is assimilated as a carbon source.

Keywords: Degradable polymer, starch based biofilms, blown film extrusion, green food packaging.

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34 Beijerinckia indica Extracellular Extract Mediated Green Synthesis of Silver Nanoparticles with Antioxidant and Antibacterial Activities against Clinical Pathogens

Authors: Gopalu Karunakaran, Matheswaran Jagathambal, Nguyen Van Minh, Evgeny Kolesnikov, Denis Kuznetsov

Abstract:

This work investigated the use of Beijerinckia indica extracellular extract for the synthesis of silver nanoparticles using AgNO3. The formation of nanoparticles was confirmed by different methods, such as UV-Vis absorption spectroscopy, XRD, FTIR, EDX, and TEM analysis. The formation of silver nanoparticles (AgNPs) was confirmed by the change in color from light yellow to dark brown. The absorbance peak obtained at 430 nm confirmed the presence of silver nanoparticles. The XRD analysis showed the cubic crystalline phase of the synthesized nanoparticles. FTIR revealed the presence of groups that acts as stabilizing and reducing agents for silver nanoparticles formation. The synthesized silver nanoparticles were generally found to be spherical in shape with size ranging from 5 to 20 nm, as evident by TEM analysis. These nanoparticles were found to inhibit pathogenic bacterial strains. This work proved that the bacterial extract is a potential eco-friendly candidate for the synthesis of silver nanoparticles with promising antibacterial and antioxidant properties. 

Keywords: Antioxidant activity, antimicrobial activity, Beijerinckia indica, characterisation, extracellular extracts, silver nanoparticles.

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33 The Micro Ecosystem Restoration Mechanism Applied for Feasible Research of Lakes Eutrophication Enhancement

Authors: Ching-Tsan Tsai, Sih-Rong Chen, Chi-Hung Hsieh

Abstract:

The technique of inducing micro ecosystem restoration is one of aquatic ecology engineering methods used to retrieve the polluted water. Batch scale study, pilot plant study, and field study were carried out to observe the eutrophication using the Inducing Ecology Restorative Symbiosis Agent (IERSA) consisting mainly degraded products by using lactobacillus, saccharomycete, and phycomycete. The results obtained from the experiments of the batch scale and pilot plant study allowed us to development the parameters for the field study. A pond, 5 m to the outlet of a lake, with an area of 500 m2 and depth of 0.6-1.2 m containing about 500 tons of water was selected as a model. After the treatment with 10 mg IERSA/L water twice a week for 70 days, the micro restoration mechanisms consisted of three stages (i.e., restoration, impact maintenance, and ecology recovery experiment after impact). The COD, TN, TKN, and chlorophyll a were reduced significantly in the first week. Although the unexpected heavy rain and contaminate from sewage system might slow the ecology restoration. However, the self-cleaning function continued and the chlorophyll a reduced for 50% in one month. In the 4th week, amoeba, paramecium, rotifer, and red wriggle worm reappeared, and the number of fish flies appeared up to1000 fish fries/m3. Those results proved that inducing restorative mechanism can be applied to improve the eutrophication and to control the growth of algae in the lakes by gaining the selfcleaning through inducing and competition of microbes. The situation for growth of fishes also can reach an excellent result due to the improvement of water quality.

Keywords: Ecosystem restoration, eutrophication, lake.

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32 Antimicrobial Effect of Essential oil of Plant Trigonella focnum greacum on some Bacteria Pathogens

Authors: Mehani M., Segni L.

Abstract:

The plant world is the source of many medicines. Recently, researchers have estimated that there are approximately 400,000 plant species worldwide, of which about a quarter or a third have been used by societies for medicinal purposes. The human uses of plants for thousands of years to treat various ailments, in many developing countries, much of the population trust in traditional doctors and their collections of medicinal plants to treat them. Essential oils have many therapeutic properties. In herbal medicine, they are used for their antiseptic properties against infectious diseases of fungal origin, against dermatophytes, those of bacterial origin. The aim of our study is to determine the antimicrobial effect of essential oils of the plant Trigonella focnum greacum on some pathogenic bacteria, it is a medicinal plant used in traditional therapy. The test adopted is based on the diffusion method on solid medium (Antibiogram), this method determines the sensitivity or resistance of a microorganism vis-à-vis the extract studied. Our study reveals that the essential oil of the plant Trigonella focnum greacum has a different effect on the resistance of germs. For staphiloccocus Pseudomonnas aeroginosa and Krebsilla, are moderately sensitive strains, also Escherichia coli and Candida albicans represents a high sensitivity. By against Proteus is a strain that represents a weak sensitivity.

Keywords: essential oil, microorganisme, antibiogram

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31 The Antibacterial Efficacy of Gold Nanoparticles Derived from Gomphrena celosioides and Prunus amygdalus (Almond) Leaves on Selected Bacterial Pathogens

Authors: M. E. Abalaka, S. Y. Daniyan, S. O. Adeyemo, D. Damisa

Abstract:

Gold nanoparticles (AuNPs) have gained increasing interest in recent times. This is greatly due to their special features, which include unusual optical and electronic properties, high stability and biological compatibility, controllable morphology and size dispersion, and easy surface functionalization. In typical synthesis, AuNPs were produced by reduction of gold salt AuCl4 in an appropriate solvent. A stabilizing agent was added to prevent the particles from aggregating. The antibacterial activity of different sizes of gold nanoparticles was investigated against Staphylococcus aureus, Salmonella typhi and Pseudomonas pneumonia using the disk diffusion method in a Müeller–Hinton Agar. The Au-NPs were effective against all bacteria tested. That the Au-NPs were successfully synthesized in suspension and were used to study the antibacterial activity of the two medicinal plants against some bacterial pathogens suggests that Au-NPs can be employed as an effective bacteria inhibitor and may be an effective tool in medical field. The study clearly showed that the Au-NPs exhibiting inhibition towards the tested pathogenic bacteria in vitro could have the same effects in vivo and thus may be useful in the medical field if well researched into.

Keywords: Gold Nanoparticles, Gomphrena celesioides, Prunus amygdalus, Pathogens.

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30 PCR based Detection of Food Borne Pathogens

Authors: Archana Panchapakesan Iyer, Taha Abdullah Kumosani

Abstract:

Many high-risk pathogens that cause disease in humans are transmitted through various food items. Food-borne disease constitutes a major public health problem. Assessment of the quality and safety of foods is important in human health. Rapid and easy detection of pathogenic organisms will facilitate precautionary measures to maintain healthy food. The Polymerase Chain Reaction (PCR) is a handy tool for rapid detection of low numbers of bacteria. We have designed gene specific primers for most common food borne pathogens such as Staphylococci, Salmonella and E.coli. Bacteria were isolated from food samples of various food outlets and identified using gene specific PCRs. We identified Staphylococci, Salmonella and E.coli O157 using gene specific primers by rapid and direct PCR technique in various food samples. This study helps us in getting a complete picture of the various pathogens that threaten to cause and spread food borne diseases and it would also enable establishment of a routine procedure and methodology for rapid identification of food borne bacteria using the rapid technique of direct PCR. This study will also enable us to judge the efficiency of present food safety steps taken by food manufacturers and exporters.

Keywords: food borne pathogens, PCR, food safety, rapiddetection.

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29 Production of H5N1 Hemagglutinin inTrichoplusia ni Larvae by a Novel Bi-cistronic Baculovirus Expression Vector

Authors: Tzyy Rong Jinn, Nguyen Tiep Khac, Tzong Yuan Wu

Abstract:

Highly pathogenic avian influenza (HPAI) H5N1 viruses have created demand for a cost-effective vaccine to prevent a pandemic of the disease. Here, we report that Trichoplusia ni (T. ni) larvae can act as a cost-effective bioreactor to produce recombinant HA5 (rH5HA) proteins as an potential effective vaccine for chickens. To facilitate the recombinant virus identification, virus titer determination and access the infected larvae, we employed the internal ribosome entry site (IRES) derived from Perina nuda virus (PnV, belongs to insect picorna like Iflavirus genus) to construct a bi-cistronic baculovirus expression vector that can express the rH5HA protein and enhanced green fluorescent protein (EGFP) simultaneously. Western blot analysis revealed that the 70 kDa rH5HA protein and partially cleaved products (40 kDa H5HA1) were generated in T. ni larvae infected with recombinant baculovirus carrying the H5HA gene. These data suggest that the baculovirus-larvae recombinant protein expression system could be a cost-effective platform for H5N1 vaccine production.

Keywords: Avian Influenza, baculovirus, hemagglutinin, Trichoplusia ni larvae

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28 Encapsulation of Satureja khuzestanica Essential Oil in Chitosan Nanoparticles with Enhanced Antifungal Activity

Authors: Amir Amiri, Naghmeh Morakabati

Abstract:

During the recent years the six-fold growth of cancer in Iran has led the production of healthy products to become a challenge in the food industry. Due to the young population in the country, the consumption of fast foods is growing. The chemical cancer-causing preservatives are used to produce these products more than the standard; so using an appropriate alternative seems to be important. On the one hand, the plant essential oils show the high antimicrobial potential against pathogenic and spoilage microorganisms and on the other hand they are highly volatile and decomposed under the processing conditions. The study aims to produce the loaded chitosan nanoparticles with different concentrations of savory essential oil to improve the anti-microbial property and increase the resistance of essential oil to oxygen and heat. The encapsulation efficiency was obtained in the range of 32.07% to 39.93% and the particle size distribution of the samples was observed in the range of 159 to 210 nm. The range of Zeta potential was obtained between -11.9 to -23.1 mV. The essential oil loaded in chitosan showed stronger antifungal activity against Rhizopus stolonifer. The results showed that the antioxidant property is directly related to the concentration of loaded essential oil so that the antioxidant property increases by increasing the concentration of essential oil. In general, it seems that the savory essential oil loaded in chitosan particles can be used as a food processor.

Keywords: Chitosan, encapsulation, essential oil, nanogel.

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27 Papain Immobilized Polyurethane Film as Antimicrobial Food Package

Authors: M. Cynthya, V. Prabhawathi, D. Mukesh

Abstract:

Food contamination occurs during post process handling. This leads to spoilage and growth of pathogenic microorganisms in the food, thereby reducing its shelf life or spreading of food borne diseases. Several methods are tried and one of which is use of antimicrobial packaging. Here, papain, a protease enzyme, is covalently immobilized with the help of glutarldehyde on polyurethane and used as a food wrap to protect food from microbial contamination. Covalent immobilization of papain was achieved at a pH of 7.4; temperature of 4°C; glutaraldehyde concentration of 0.5%; incubation time of 24h; and 50mg of papain. The formation of -C=Nobserved in the Fourier transform infrared spectrum confirmed the immobilization of the enzyme on the polymer. Immobilized enzyme retained higher activity than the native free enzyme. The modified polyurethane showed better reduction of Staphylococcus aureus biofilm than bare polymer film (eight folds reduction in live colonies, two times reduction in protein and 6 times reduction in carbohydrates). The efficacy of this was studied by wrapping it over S. aureus contaminated cottage cheese (paneer) and cheese and stored at a temperature of 4°C for 7days. The modified film reduced the bacterial contamination by eight folds when compared to the bare film. FTIR also indicated reduction in lipids, sugars and proteins in the biofilm.

Keywords: Cheese, Papain, polyurethane, Staphylococcus aureus.

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26 Detection of Arcobacter and Helicobacter pylori Contamination in Organic Vegetables by Cultural and PCR Methods

Authors: Miguel García-Ferrús, Ana González, María A. Ferrús

Abstract:

The most demanded organic foods worldwide are those that are consumed fresh, such as fruits and vegetables. However, there is a knowledge gap about some aspects of organic food microbiological quality and safety. Organic fruits and vegetables are more exposed to pathogenic microorganisms due to surface contact with natural fertilizers such as animal manure, wastes and vermicompost used during farming. Therefore, the objective of this work was to study the contamination of organic fresh green leafy vegetables by two emergent pathogens, Arcobacter spp. and Helicobacter pylori. For this purpose, a total of 24 vegetable samples, 13 lettuce and 11 spinach were acquired from 10 different ecological supermarkets and greengroceries and analyzed by culture and PCR. Arcobacter spp. was detected in five samples (20%) by PCR, four spinach and one lettuce. One spinach sample was found to be also positive by culture. For H. pylori, the H. pylori VacA gene-specific band was detected in 12 vegetable samples (50%), 10 lettuces and two spinach. Isolation in the selective medium did not yield any positive result, possibly because of low contamination levels together with the presence of the organism in its viable but non-culturable form. Results showed significant levels of H. pylori and Arcobacter contamination in organic vegetables that are generally consumed raw, which seems to confirm that these foods can act as transmission vehicles to humans.

Keywords: Arcobacter spp., Helicobacter pylori, organic vegetables, Polymerase Chain Reaction, PCR.

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25 Antimicrobial Effect of Essential Oil of Plant Schinus molle on Some Bacteria Pathogens

Authors: Mehani M., Segni L.

Abstract:

Humans use plants for thousands of years to treat various ailments, in many developing countries; much of the population relies on traditional doctors and their collections of medicinal plants to cure them.

Essential oils have many therapeutic properties. In herbal medicine, they are used for their antiseptic properties against infectious diseases of fungal origin, against dermatophytes, those of bacterial origin.

The aim of our study is to determine the antimicrobial effect of essential oils of the plant Schinus molle on some pathogenic bacteria. It is a medicinal plant used in traditional therapy. Essential oils have many therapeutic properties. In herbal medicine, they are used for their antiseptic properties against infectious diseases of fungal origin, against dermatophytes, those of bacterial origin.

The test adopted, is based on the diffusion method on solid medium (Antibiogram), this method allows to determine the susceptibility or resistance of an organism according to the sample studied.

Our study reveals that the essential oil of the plant Schinus molle has a different effect on the resistance of germs: for Pseudomonas aeruginosa strain is a moderately sensitive with an inhibition zone of 10mm, further Enterobacter, Escherichia coli and Proteus are strains that represent a high sensitivity, a zone of inhibition equal to 14.66 mm.

Keywords: Essential oil, microorganism, antibiogram, Shinus molle.

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