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Examination of the usability of the MALDI-TOF method in sunflower genetic identity analyses
33-38Views:147Economically, one of our most important crop is the sunflower. Regarding its production it is essential to use top quality seeds. As the conditions of seed certification and the certification parameters are regulated by laws and ordinances, it is highly important to farmers and seed producers to detect seeds of low quality or dubious origins.
Nowadays, the examination of the cultivar homogenity of sunflower is based on a reference method of the International Seed Testing Association Rules International (ISTA), Chapter 8. This standard reference method uses ultrathin poliakrilamid isoelectric focusing gel electrophoresis (IEF-UTL, or simply IEF). With this work we have set out to compare the results of MALDI-TOF to the test results – used as reference results – achieved by this reference method. The aim is to develop a new, quick, cheap and reliable method. In this article I summarized the results of some of the experiments that will provide basis for my further work.
During our previous experiments we have concluded that out of four extracting agents we can get the most protein markers using NaCl acid buffer, 1 propanol buffer. -
Application of the SDS-PAGE method for the characterisation of winter wheat flour quality
112-118Views:101The principle, development and importance of the SDS-PAGE method are presented in this article. The SDS-PAGE method has become one of the basic methods of molecular biological research, because it is widely applicable and its sensitivity is excellent in the separation of wheat storage proteins.
We have shown the application of this method with a concrete example. It was also tested whether, it was possible to obtain a better baking quality product from a large amount of poor quality less valuable wheat by fractioning the flour according to particle sizes after grinding. We studied the rheological properties of flours with different particle size fractions from the original flour. The baking quality of the original flour was B2. The 125-90 and 90-63 μm fractions have significantly better baking quality (B1) than the original flour. The protein contents of these flour fractions were also significantly higher than the protein content of the original flour. We had a question: what has influenced the baking quality: the protein content or other factors? We searched for an explanation on these results in the protein composition of the flour samples. We studied the distribution of glutenin-fractions by SDS-PAGE method and evaluated them. We found with correlation analysis that the amount of LMW-Glutenin D-group (52-60 kDa) is in a strong, negative correlation to the baking quality (r = – 0.855*). Therefore, the baking quality of flour samples was influenced by this glutenin fraction. -
The Evaluation of Grazed Grasslands on the Hortobágy
50-54Views:111The sward composition of different grasslands on Puszta Hortobágy has been developed according to prevailing abiotic and biotic factors. The abiotic conditions have been more or less constans for long periods of time, and the abiotic factors are determined by ecological conditions (climate, soil, topography). Among biotic factors grazing of herbivores was important in the development of Hortobágy grasslands for centuries (Sipos and Varga, 1993). Result of three-year investigations on the sward composition of grasslands utilised in different ways are presented. Data on ground cover, number of plant species, representation of different plant groups (grasses, sedge and bent-grass, herbs, legumes) and weeds are reported from six different grazed grassland types from Puszta Hortobágy.
In 1999-2001 a sward composition survey was conducted. Sample areas of 2x2 m2 were marked out in three replicates: on temporarily waterlogged grassland grazed by cattle (A), on dry grassland grazed by cattle (B), on dry grassland grazed by sheep (C), on dry grassland grazed by buffaloes (D), on dry grassland grazed by buffaloes and geese (E), on dry grassland cut for hay in May then grazed by geese (F). On the sample areas sward composition of grasslands was estimated according to Balázs (1949).
The average ground cover of different grasslands ranged between 60 and 100% (Table 2). The lowest value was found for grasslands C and E, which are grazed by sheep (C) and buffaloes and geese alternately (E). In these grasslands were some open spaces, on the other grasslands completely closed swards covers were observed.
The species diversity of these natural grasslands are high (Table 2). The grassland F, which were cut for hay in May had the lowest diversity (17-21). The highest number of species was found on grassland A and B (32-51), on other grazed grasslands (C, D, E) had 29-48 species.
The different plant groups had different representation in the total ground cover (Table 3). The number of herbs was always higher then that of grasses, but the cover of herbs was lower then that of grasses. The legumes and the sedge and bent grasses were present in high abundance in grassland A, but in the other grasslands were not.
The composition of herbs should be a warning for future utilisation systems on some grasslands of Hortobágy. Some species of herbs, e.g. Achillea millefolium, Artemisia vulgaris, Carduus acanthoides, Cirsium arvense, Cirsium vulgare Eryngium campestre, Galium mollugo, Galium verum, Ononis spinosa, Rumex crispus, Verbascum phlomoideus, Phragmites australis can be invasive on short grasslands. -
The composition of gluten proteins and their effect on the rheological properties of gluten
124-129Views:119Wheat is the major cereal component of bread in the world and is grown worldwide. Of the cereals only the bread wheats – and less the triticale – includes storage proteins that play an important role in the performance of gluten. Proteins of gluten complex may be present in two classes:
− low molecular weight (gliadin-) components, and
− high molecular weight (glutenin-) components.
Gliadins shown appreciable heterogenity and can be separated into 40-50 components with gel electrophoresis. The composition of gliadins is employable for the identification the wheat varieties and to investigate the varieties. In the decreasing electrophoretic mobility sequence may be distinguish α-, β-, γ- and ω-gliadins. A glutenin subunits may be include in two classes:
− high molecular weight glutenin subunits (HMW-GS),
− low molecular weight glutenin subunits (LMW-GS).
Wheat varieties can be identified by glutenin and their quality selection is also possible. The gliadin’s polypeptides encoding genes are located on the short arm of chromosomes 1A, 1B and 1D, 6A, 6B and 6D. Genetic coding for HMW subunits is located on the long arms of chromosomes 1A, 1B and 1D, the LMW-GS are also located on chromosomes 1A, 1B and 1D (Glu-3 loci) near the gliadin-coding loci.
Storage proteins affect the rheological properties of gluten by two factors:
1. The quality and quantity of the protein components of the gluten complex,
2. The interactions between the protein fractions. -
Development of seed analyses by means of various matrix solutions and the MALDI-TOF MS technique
53-57Views:273The earth's population is growing steadily, currently accounting for about 7.3 billion people. Population growth causes food demand to rise, approximately 36 million people die each year due to starvation or related diseases. One solution to this problem is the continuous examination and development of the agricultural economy. In this study, matrix-assisted laser desorption/ionization time-of-flight mass spectrometer (MALDI -TOF MS) were used to analyse of sunflower, soybean and hemp. In order to analyse the protein of maize, this method has already been applied. However, for sunflower, soy and hemp, it is necessary to develop a sample preparation method. Choosing the optimal matrix solution for ionization the traget molecule is an essential part of developing the method. Our aim is to compare two different matrix solutions (α-HCCA, SA matrix), based on the properties (intensity, noise ratio, value of spectra) of the spectra.