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Effect of Selenium Supplementation on in vitro Radish and Green Pepper Seedlings Germination
149-155Views:787Selenium (Se) is an essential trace element for animals, microorganisms and some other eukaryotes. It has become increasingly evident that Se plays a significant role in reducing the incidence of lung, colorectal and prostate cancer in humans. Although there is evidence that selenium is needed for the growth of algae, the question of essentiality of Se in vascular plants is unresolved. Therefore Raphanus sativus (Se accumulator) and Capsicum annuum (non Se accumulator) were treated with 0-200 mg/l natrium-selenate. The results showed that lower (2 mg/l) concentration natrium-selenate increased the fitomass and total antioxodant capacity in seedlings.
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Management of phytopathogens by application of green nanobiotechnology: Emerging trends and challenges
15-22Views:647Nanotechnology is highly interdisciplinary and important research area in modern science. The use of nanomaterials offer major advantages due to their unique size, shape and significantly improved physical, chemical, biological and antimicrobial properties. Physicochemical and antimicrobial properties of metal nanoparticles have received much attention of researchers. There are different methods i.e. chemical, physical and biological for synthesis of nanoparticles. Chemical and physical methods have some limitations, and therefore, biological methods are needed to develop environment-friendly synthesis of nanoparticles. Moreover, biological method for the production of nanoparticles is simpler than chemical method as biological agents secrete large amount of enzymes, which reduce metals and can be responsible for the synthesis and capping on nanoparticles.
Biological systems for nanoparticle synthesis include plants, fungi, bacteria, yeasts, and actinomycetes. Many plant species including Opuntia ficus-indica, Azardirachta indica, Lawsonia inermis, Triticum aestivum, Hydrilla verticillata, Citrus medica, Catharanthus roseus, Avena sativa, etc., bacteria, such as Bacillus subtilis, Sulfate-Reducing Bacteria, Pseudomonas stutzeri, Lactobacillus sp., Klebsiella aerogenes, Torulopsis sp., and fungi, like Fusarium spp. Aspergillus spp., Verticillium spp., Saccharomyces cerevisae MKY3, Phoma spp. etc. have been exploited for the synthesis of different nanoparticles. Among all biological systems, fungi have been found to be more efficient system for synthesis of metal nanoparticles as they are easy to grow, produce more biomass and secret many enzymes. We proposed the term myconanotechnology (myco = fungi, nanotechnology = the creation and exploitation of materials in the size range of 1–100 nm). Myconanotechnology is the interface between mycology and nanotechnology, and is an exciting new applied interdisciplinary science that may have considerable potential, partly due to the wide range and diversity of fungi.
Nanotechnology is the promising tool to improve agricultural productivity though delivery of genes and drug molecules to target sites at cellular levels, genetic improvement, and nano-array based gene-technologies for gene expressions in plants and also use of nanoparticles-based gene transfer for breeding of varieties resistant to different pathogens and pests. The nanoparticles like copper (Cu), silver (Ag), titanium (Ti) and chitosan have shown their potential as novel antimicrobials for the management of pathogenic microorganisms affecting agricultural crops. Different experiments confirmed that fungal hyphae and conidial germination of pathogenic fungi are significantly inhibited by copper nanoparticles. The nanotechnologies can be used for the disease detection and also for its management. The progress in development of nano-herbicides, nano-fungicides and nano-pesticides will open up new avenues in the field of management of plant pathogens. The use of different nanoparticles in agriculture will increase productivity of crop. It is the necessity of time to use nanotechnology in agriculture with extensive experimental trials. However, there are challenges particularly the toxicity, which is not a big issue as compared to fungicides and pesticides.
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The effect of season on the microbiological status of raw milk
95-99Views:720Many factors can influence the microbiological quality of raw cow’s milk. In this study, our aim was to determine whether there was any difference between the microbiological statuses of milk produced in different seasons. Samples were collected and analysed from five dairy farms in Hajdú-Bihar County, from February to November in 2019. During our studies, total plate count (TPC), coliform count and Staphylococcus aureus count of raw cow’s milk samples were determined.
There was no significant difference (P>0.05) between the mean TPC values detected in the milk collected in winter and autumn, but that values were significantly (P<0.05) lower than in the milk samples collected in spring and summer. Similarly to the TPC, in the case of coliform bacteria the lowest mean colony count was detected in the samples collected in winter. The difference was significant (P<0.05), compared to the values observed in the samples collected in summer. S. aureus was detected in bulk milk of only two farms in excess of 1.0 log10 cfu/ml. Also in case of S. aureus, there was a significant difference (P<0.05) between the values observed in the samples collected in winter and in summer. Samples from spring and summer contained the highest amount of S. aureus.
Based on the results of our studies, in the case of almost all farms the mean TPC, coliform and S. aureus counts were lower in the samples collected in winter, than in the samples collected in summer. The fact that the samples collected in winter contained the lowest amount of colonies could be attributed to the inhibition of growth of mesophilic microorganisms below 8 °C. Furthermore, the fact that we observed the highest colony counts in samples collected in summer, can be related to the heat stress of cows during the summer due to unfavorable weather conditions (high temperature and humidity).
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The effect of apoplastic pH on the nutrient uptake
65-71Views:254The pH of soil and rhizosphare –around the roots- determine the mobility and solubility of nutrients. The exudates organic acids of plant able to modify the pH, as well as the microorganisms also take part in mobilization of nutrients. The nutrient solve mostly in mildly acidic and neutral pH. The either assumption of utilization of nutrients is the uptake by roots and of course uptake to the cells to take part in metabolism. The pH of apoplast fluid determines the solubility and uptake of nutrients to the cells.
The aim of this study was to examine the effect of nutrient solution and apoplastic pH together with a bacteria based biofertiliser (Phylazonit MC®) on nutrient uptake and pH of apoplast fluid in case of nutrient solution grown plants in laboratory experiment. According to my results, the bicarbonate increased the pH of nutrient solution in due to influence the solubility and uptake of nutrients. The given bicarbonate to the nutrient solution and infiltrated into the apoplazma also modified the pH of the apoplast fluid of the test plants. The effect of bicarbonate and biofertilizer were different on the pH of the apoplast fluid and nutrient solution in nutrient solution experiment. -
Effect of Ozone Exposure on Phytopathogenic Microorganisms on Stored Apples
9-13Views:283The aim of our study was to clarify the effect of ozone exposure on several phytopathogenic fungi on stored apple fruits under different storage conditions. The study was conducted at Bistrita, Romania, in the storehouse of an experimental apple orchard in 2002 and 2003. Two widely grown apple cultivars (‘Jonathan’ and ‘Golden Delicious’) were used. General microbial examination of the fruits was made during storage in order to identify the most important storage pathogens. Efficacy of six ozone treatments was evaluted on fruit decay caused by phytopathogenic fungi. Monthly observations (January, February, March and April) were made of the degree of decay and three measurements were assessed (disease frequency, disease intensity and degree of attack). Our results showed that the most important phytopathogenic fungi during storage was blue mold, caused by species of Penicillium. Disease frequency of apple fruits was very high on cv. ‘Jonathan’, much higher than on cv. ‘Golden delicious’. Ozone treatments (25 ppm ozone for 0.5 and 1.5 hours in November) caused significantly lower disease incidence on stored apple than all other ozone treatments. For longer storage, it seems that additional ozone treatments in February increased treatment efficacy. Cv. ‘Golden delicious’ seemed to be more resistant to storage diseases than cv. ‘Jonathan’ both on the untreated and treated fruits. The effect of the ozone treatments was also the most effective when 25 ppm ozone was applied for 0.5 and 1.5 hours in November.
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Evaluation of the microbial soil quality indicators in agricultural soils from Crisurilor Plain
79-80Views:268The researches were carried out in 2010 and 2011 on the haplic luvisol cultivated in three variant such as: pasture, cropland, and orchards. Based on the total number of microorganisms monitored in the haplic luvisol (aerobic mesophilic heterotrophs, yeast and mould, Actinomycetes, nitrogen fixing bacteria and nitrifying bacteria) was calculated the bacterial indicators of soil quality (BISQ) and was appreciate the bacterial potential of the haplic luvisol. Seasonal analyses were carried out, and annual BISQs have been calculated too. The values of the bacterial indicators of the haplic luvisol in different cultivation conditions (pasture, cropland and orchards) indicate a high density of the bacterial groups in 2010 and 2011. In 2010 the values of the BISQs are included between 3.617 (minimum in autumn, in pasture) and 5.458 (maximum, in spring, in pasture). In 2011, the minimum value (3.622) was registered in pasture, in autumn, and the maximum value (4.851) in the haplic luvisol cultivated with maize, in spring. In 2010 and 2011, based on the bacterial indicators of the soil quality values, on the first position is the cropland (4.750, 4.721) followed by orchards (4.615, 3.985) and pasture (4.537, 3.758).
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Characterisation of a thermotolerant yeast, Kluyveromyces marxianus CBS712
7-13Views:503Fermentation at high temperature with application of thermotolerant microorganisms is a technological advantage in bioethanol production. Among the yeasts, K. marxianus has outstanding thermotolarance. The industrial application of the IMB3 strain occurs usually at 45C. The final aim of our project is the genetic modification of the K. marxianus CBS712 strain in order to achieve ethanol production at higher temperature than the currently applied. This requires the characterization of the CBS712 strain, with special attention to the determination of the temperature limit of its growth and the amount of the ethanol produced. The temperature limit of growth was 48C in YPD medium. Elevation of the temperature above 45C led to an exponential drop of the cell viability. Ethanol production was tested in shaking flasks, in MYFM medium, under oxigene limited conditions, applying variable concentrations of glucose (12–20%) and different temperatures (45–47 ºC). Preliminary results have revealed that the elevation of glucose concentration increased the amount of ethanol produced. The amount of ethanol (appr. 5%)+ produced at the highest glucose concentration was not different at the tested temperatures (45, 46 and 47 ºC). The observation indicates the potential in raising the thermotolerance of the strain.
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Effect of cadmium and zinc contamination on the population dynamics of soil microorgani
73-77Views:304Changes in the population dynamics of microorganisms in a soil artificially contaminated with various doses of cadmium and zinc was examined from a quantitative point of view, under laboratory circumstances. The research was based on a chernozem soil originating from the area of a long-term microelement contamination model experiment (Nagyhörcsökpuszta, Hungary), which was carried out during 1991 in the Experimental Site of the Institute of Soil Science and Agricultural Chemistry, Centre for Agricultural Researche Hungarian Academy of Sciences, Budapest, Hungary. According to the amount of bacteria, microscopic fungi and nitrifying bacteria, it can be stated that the effect of contamination can be observed even in the perspective of nearly two decades. In more cases significant changes in the number of soil bacteria and microscopic fungi could be observed, and the nitrification activity increased in case of both microelements. Therefore the further research of changes in microbial activity of these soils can provide novel scientific results.
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The toxic effects of aflatoxin microorganisms in plants used as spices
59-62Views:261As an extension of the analysis of black, white and capsicum peppers for aflatoxins , we have examined an additional 11 types of spices and
4 herbs for these mycotoxins. The investigations consisted of assessment of the applicability of available methods of analysis and modifications of
these, where necessary together, with a limited survey of each spice and herb for aflatoxins. The analysis of 13 types of ground spices reported
the presence of low concentrations of aflatoxins in some samples of black pepper, celery seed, and nutmeg. We decided to include in our study 5
of the spices examined by these workers (cinnamon, celery seed, coriander, nutmeg, and turmeric) for a comparison purpose. In addition we
examined ginger, mace, cumin seed, dill seed, garlic powder, onion powder, and the herbs marjoram, rosemary, thyme, and sage. -
Testing the antimicrobial activity of essential oils
71-74Views:322The vapor phase of some essential oils proved to have antimicrobial activity. Utilization of the vapor phase of Eos is presently understood as one of the possible alternatives to synthetic food preservatives which could be used in the future. However, testing the vapor phase of EOs against microorganisms causing food-borne diseases (e.g. Salmonella enteritidis or Staphylococcus aureus) or food spoilage is relatively new. Consequently, due to the large number of known EOs, research on their antimicrobial activity is still largely in the phase of in vitro rather than in vivo testing. Moreover, no standard and reliable method for fast screening of a wide range of samples exists. Thus, the aim of this study is to show results concerning tests of the antimicrobial activity of EOs against S. enteritidis or S. aureus, which were conducted by two modifications of the disc volatilization method we developed. The lately developed method has the potential to become widely used for fast screening of EO antimicrobial activity in the vapor phase.
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Microbiological quality of bulk tank raw milk from two dairy farms in Hajdú-Bihar County, Hungary
105-112Views:748Two main channels have been identified to be responsible for microbiological contamination of raw milk and milk products. Firstly, contamination has occurred due to udder infection from the cow or the blood which harbours most bacteria that come in contact with the raw milk. Secondly, via external factors (may include faeces, skin, contaminated water, environment etc.) which are associated with the operation of milking. There is direct contact with the milk and/or surfaces before, during or after the milking, posing public health risk and economic decline. The aim of this study was to examine the bacteriological quality of bulk tank raw milk samples collected from two different size dairy farms (Farm 1 and Farm 2) of different housing forms (cubicle loose and deep litter) in Hajdú-Bihar County, Hungary in July, 2017. Three samples were taken from each farm, and the total plate count, coliform count, Escherichia coli count, Staphylococcus aureus count, and yeast and mould count were determined in them.
The results clearly showed low level of all measured bacteria group load in Farm 1 samples in comparison to Farm 2 with the exception of coagulase-negative Staphylococcus (CNS) which represented high level in general, indicating significant difference (P<0.05). The mean value of total plate count in Farm 2 samples was higher (1.0 × 105 CFU/mL) than Farm 1 samples (2.8 × 104 CFU/mL). There was a significant difference (P<0.05) in mean count of coliforms in raw milk samples between Farm 1 and Farm 2. Similarly, results of E. coli were significantly different (P<0.05) with mean count of 1.44 × 102 CFU/mL and 2.02 × 103 CFU/mL for Farm 1 and Farm 2 respectively.
Results of Staphylococcus aureus also showed significant difference (P<0.05) with mean count of 9.7 × 101 CFU/mL for Farm 1 and 6.28 × 102 CFU/mL for Farm 2. The mean of mould count recorded was 1.07 × 102 CFU/mL and 4.93 × 102 CFU/mL for Farm 1 and Farm 2 respectively. The recorded mean of yeast count was 1.68 × 103 CFU/mL and 3.41 × 103 CFU/mL for Farm 1 and Farm 2 respectively; however, both farms showed no significant difference (P>0.05) in terms of mean of mould and yeast count. Although Farm 2 produced six times lower milk quantity than Farm 1, the measured microbial parameters were high. Both farms’ microbiological numbers were higher above the permitted limit values as stated by Regulation (EC) No 853/2004, Hungarian Ministry of Health (MoH) 4/1998 (XI. 11.).
This could be an indication of non-conformance to effective GMP, ineffective pre–milking disinfection or udder preparation, poor handling and storage practice, time and temperature abuse and inadequate Food Safety Management System Implementation. Therefore, our recommendation is as follows; establish control measures for pre- and postharvest activities involved in the milking process which would be an effective approach to reduce contamination of the raw milk by pathogenic microorganisms from these farms, strict sanitation regime and hygiene protocol be employed and applied to cows, all equipment, contact surfaces and minimize handling of the milk prior, during and after milking. This will also serve as scientific information to the producers for continual improvement in their operations.
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The effect of keeping technology on the microbiological status of raw milk
67-75Views:664The importance of the quality of raw milk increased after Hungary had joined to the EU. On delivery of raw milk, the microbiological quality, especially total plate count of the milk is very important. Twenty-two farms (7 large, 4 medium-sized, and 11 small farms) were included in the study. We considered the different farm size, keeping- and milking circumstances during the selection of farms. The examined large farms use loose housing system (cubicle, deep litter) and milking parlour. Most of them use preand post-milking disinfection. In the medium-sized farms, loose,
deep litter and tie-stall housing system, as well as milking parlour, pipeline milking and bucket milking occurred. All of them use preand post-milking disinfection. Small farms use tie-stall housing system, bucket milking and udder preparation by water. Unfortunately, they do not use pre- or post-milking disinfection. In the large and medium-sized farms mainly Holstein Friesian, in the small farms Hungarian Simmental breeds can be found.
The aim of our research was to examine the microbiological status of the raw milk produced in dairy farms (total plate count, coliform count, Escherichia coli count, Staphylococcus aureus count, psychrotroph bacteria count, furthermore yeast and mold count); sources of the contamination; connection between the microbiological quality of produced milk and housing-, milking technologies of farms; furthermore the hygienic circumstances of milking and milk handling of the farms, by the examination of coliform bacteria and Escherichia coli contamination.
During the examination of the connection between the different farm sizes, various housing- and milking forms and the microbiological characteristics we observed similar tendencies in the case of total plate count, coliform count, yeast and molds count, furthermore psychrotroph bacteria count. The value of these parameters was significantly higher in small farms, and infarms which use tie-stall housing forms, bucket milking, udder preparation with water, and which do not use pre- and post-milking disinfection.
The results showed that besides cooling, the milking procedure and the type of udder preparation had the largest effect on the total plate count. Statistical analysis shows that in medium and small farms the combination of pipeline milking – tie stall housing system – disinfectant preparation of the udder; in large farms the combination of milking parlour – loose cubicle housing system – dry preparation of the udder are the most appropriate in the aspect of the total plate count. We experienced that in farms where the hygienic instructions are not followed – and therefore
equipment used during the milking and handling of milk is very contaminated – or rather the separation of mastitic cows’ milk is not appropriate, different microorganisms may contaminate the produced milk. -
Saccharomyces cerevisiae growth kinetics study dairy byproduct
169-172Views:672By guess, annual volume of milk whey is 185–190 million tons and this volume probably will increase next years. Whey has significant biochemical oxygen demand due to its high organic matter content so whey as sewage is one of the most pollutant by-products in the food industry. Apart from environmental pollution, benefit of several whey constituents for human health is another reason to utilize whey. Corn and potato, as well as the processing of milk in the food industry in large quantities of by-products generated by low cost, substantial quantities of starch and lactic acid, which are due to high biological oxygen demand are considered as hazardous waste. Some of them are destroyed sewage storage tanks, and those products are excellent substrates for the growth of microorganisms could be. The traditional nutrient solution optimization methods are solution and time-consuming and are not able to determine the real optimum because of the interaction of factors involved.
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Antimicrobial effect of dried sage on the microbiological state of fresh Hungarian sausage
189-192Views:337The purpose of this study was to evaluate the microbial effect of dried sage (Salvia officinalis L.) on the traditional Hungarian sausage. We added 0.5, 1, 1.5, and 2 w/w% of sage to the sausages and tested them on the 0th, 7th and 14th day. The added dried sage had no effect on the tested microorganisms, but the sage extract inhibited Salmonella, Enterococcus faecium and Staphylococcus aureus.
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Usage of microbiological products in the protection of the sunflower
36-40Views:237White mould is the most important desease of sunflower. We are not able to grow sunflower on the same area for 5-6 years, because of sclerotia. One of the protection methods is if we destroy the sclerotia in the soil with hyperparasite microorganisms, so we can reduce the comeback time of sunflower.
We carried out our farm size researches through 3 years, with the most important sunflower hybrids of Hungary in the area of Vásárhelyi Róna Kft. We can conclude that the microbiological products (Koni, Trifender, Mico’sol) effect positively on the yield of sunflower hybrids, but the weather (moisture) can significantly modify this effect.
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Essential oil extraction from herbs and their use in the food industry
59-74Views:664Essential oil extraction of wild caraway and thyme was performed using a classical (HD) and microwave hydro-distillation (MWHD) and a laboratory supercritical fluid extraction (SFE) with a carbon dioxide as solvent. Our experiments demonstrated that the extraction yield of the essential oil performed in same conditions was influenced by the location of growth area; the maximum extraction yield of 10 ml 100 g-1 caraway was obtained from dried seeds collected from Csíkmadaras. This quantity far exceeded the yield of the Újtusnád samples. In the case of wild caraway (Carum carvi L.), the extraction method influenced thecomposition of the essential oil (carvone/limonene ratio), the highest limonene content being achieved by classical hydro-distillation. In the case of thyme, this effect was not detected, the thymol/carvacrol ratio was independent from the given extraction method. The obtained thyme essential oil possesses high antimicrobial activity demonstrated by agar diffusion test. The thyme extract provides a good protection against microorganisms collected on the surface of fresh vegetables following bacterial stains: Citrobacter portucalensis, Pseudomonas hunanensis, Pseudomonas baetica, Pseudomonas parafulva, Bacillus mojavensis and Enterobacter cloacae. Protective effect was also detected on the vegetable surface of by chitosan-based edible film coating during a 6-day-long storage period at a temperature of 4 °C. The caraway essential oil used as soft cheese seasoning with a direct, dilution-free method, proved to be unsuitable because the uneven distribution and confer a strong, unpleasant taste to the product in comparison with the ground wild caraway seed-dressed cheese.
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Bacteria in the milk of sheep with or without mastitis- mini Review
47-52Views:797From a nutritional point of view, sheep milk is more valuable than cow and goat milk and the interest for sheep milk is increasing in many countries. However, sheep milk is easily contaminated during milking, handling, and transport and it is an ideal medium for bacterial propagation. Consequently, sheep milk spoils quite quickly. The proper, clean handling of milk is not only of sanitarian interest, but it also serves the farmers’ interests, because contaminated milk may not be distributed, and is unsuitable for producing good quality products. Following this technological trend, this review addresses the bacterial composition of sheep milk with and without mastitis. Even though sheep milk contains a lot of bacteria, this review article highlighted total plate count, Enterobacteriaceae, coliform, Staphylococcus aureus, Escherichia coli, Listeria monocytogenes, Campylobacter, Salmonella spp. and Streptococcus spp. Mastitis in sheep is a vital cause of mortality, reduction in milk production and early culling. The reported risk factors for mastitis in sheep were age, a case of mastitis, breed, husbandry systems, and location. The main priority should be implementation of programs to minimize human pathogenic bacteria and mastitis in raw ewe milk.
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Effects of some herbicides on the microbiological characteristics of soil nitrogen cycle under maize plantation
93-100Views:382Nitrogen is a key element for the living organisms and influence not only for the quantity but for the quality of the yield, considerable. Availability of nitrogen from the soil is influenced by several microbiological processes of the Nitrogen-cycle. Among the intensive agricultural production the herbicide application cannot be omitted more information needs therefore about the inhibitor effect of herbicides on the different microorganisms.
An experiment was set up on calcareous chernozem soil under maize culture. Effect of four different herbicides (Acenit, Frontier, Merlin, and Wing) was investigated. The effect of herbicides was measured to four microbiological parameters of the Nitrogencycle (abundance of nitrifying bacteria, nitrate solubilisation, biomass nitrogen and urease enzyme activity). There were singledouble- and five times of recommended doses of herbicides applied for two onsecutive vegetation periods.
From the results of the different doses of herbicides, the following can be stated:
– The Acenit has a stimulating effect on nitrifying bacteria in general. The Frontier and Merlin also influenced the quantity of nitrifyers, however in certain cases decreased in another cases increased the number of bacteria.
– The double doses and five times doses of herbicides was found to be increasing the nitrate content of soil, -especially in 2006.
– The quantity of microbial biomass nitrogen increased in the 60% of treatments and decreased in the 40% of the treatments.
– Except of the result of Wing in 2006 and Merlin in 2005, the effect of simple dose herbicides was the smallest on the urease enzyme activity. According to the results the effect of Merlin was positive; the effect of Wing was negative on the soil enzyme’s activity.
Regarding the application of four different herbicides in three different doses on the microbiological parameters of soil (at two consecutive years-) in 39% of the treatments has resulted a significant inhibitory effect, 28% of the treatments, however have significant stimulating effect on the parameters measured. More than 50% of the inhibitory effect was measured in case of the Wing, at more than 50% of the Frontier the microbiological parameters have not changed.