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The content of potentially antioxidant, anticarcinogenic and antiallergic flavonoid aglycons, quercetin, kaempferol, myricetin, apigenin and luteolin of 45 fruits were determined by RP-HPLC with UV detection. Fresh and dried fruits were purchased in the local markets in Budapest at a period of their most frequent consumption. Total flavonoid content of fruits varied between 0–1000 mg kg –1, the average concentration was about 30 mg kg –1 fresh weight. Quercetin could be detected in most fruits, namely in apples, pear, plums, sweet and sour cherry and berries between 10–53 mg kg –1. Luteolin at a concentration of 20 mg kg –1 was found in melons, apples, kiwi and lemon. Myricetin was in detectable amount in redcurrant, and at very high concentration in some berry fruits (mulberry 453 mg kg –1, raspberry 540 mg kg –1, blackberry 636 mg kg –1, strawberry 994 mg kg –1), and in walnut (4565 mg kg –1). Kaempferol and apigenin were not found in the fruits investigated. None of the five flavonoids was found in some variety of grapes, in peach, pear, banana, orange, grapefruit and tangerine, in nuts such as almond, pistachio, nuts, and in dried fruits such as raisin, date, fig and prunes. These data provide a basis for the evaluation of the average daily intake of Hungarian population and for an epidemiological evaluation of health-promoting effects of flavonoids. __
Successful applications of toxins derived from Bacillus thuringiensis (Bt) strains in Bt-based bioinsecticides and more recently in Bt-plants in crop protection have enhanced the importance of analytical quantification of Cry toxin dosages for studies on various topics including environmental risk assessment (ERA), resistance management, quality control and regulatory compliance. It is essential to follow-up distribution and environmental degradation of these lectin type, crystalline (Cry) toxin proteins showing insect specificity at order level. Thus, Cry1Ab toxin produced by Bt-maize of genetic event MON 810 is specific to lepidopteran species. Widely used analytical methods for detection of Cry toxins are enzyme-linked immunosorbent assay (ELISA) systems. Reported Cry1Ab toxin concentrations in MON 810 maize show high variability: order of magnitude differences have been observed among various plant parts from different varieties, cultivated at different locations, and sometimes even within the same plant variety at a single location. Besides biological sources of variability, numerous analytical problems have been identified and are reported in this report, influencing the results of quantitative determination of Cry1Ab toxin and explaining the high variability among documented data on toxin content. Conclusions in every case refer to genetic event MON 810, but can be extended to other genetic events producing Cry1Ab toxin.
Reliable determination of microbial or transgenic Cry toxins is an essential issue in food and feed analyses, and enzyme-linked immunosorbent assays (ELISAs) are the method of choice for quantifying these toxins currently in food and environmental analysis. Internal Quality Control (IQC) is an indispensable method to assess accuracy, precision, and reproducibility of analytical measurements. To assess the utility of the ELISA method, IQC was performed on EnviroLogix Cry1Ab/Cry1Ac QualiPlate ELISA with manufacturer supplied analytical standards. Applicability of negative and positive controls (C− and C+) was examined by Shewhart Control Charts for bias and Control Chart of the Range of Duplicates for precision. Linear regression (up to 5 ng ml−1 Cry1Ab concentration) of the commercial ELISA kit was compared to sigmoid calibration (up to 60 ng ml−1 Cry1Ab concentration). For immunoassay optimization process, possible matrix effects in different liquid and solid vertebrate tissues were examined by determination of the limit of detection values in these matrices.
Epipactis albensis Nováková et Rydlo (Orchidaceae), a species previously undocumented in the flora of Ukraine, was found in three localities in this country (in vicinity of Chetfalva, Fanchykovo and Drotyntsi, Zakarpattia district) in 2012. The species (originally described from the Czech Republic) recently has only been known to exist in seven Central European countries. The three Ukrainian populations described here stretch within the floodplain of river Tisza. Based on measurements in 14 localities in Hungary, Ukraine and Romania the species has a considerably wide soil reaction tolerance (from 3.6 to 7.2 pHKCl). The fruit set of this strictly autogamous species is reasonably high (78%). The mean±SD thousand seed weight of the species was 0.0030±0.0005 grams, therefore E. albenis is classified into the hypermeichor seed-weight class. Recent discoveries of the species in Romania and Ukraine raise the possibility of its occurrence in further European countries.
The expression levels of two marker proteins (phosphinotrichin acetyltransferase, PAT and wheat germ agglutinin, WGA) in the transgenic wheat lines and their resistance to digestion in small intestine of rats were studied in comparison with their non-transgenic counterpart obtained from green house and field experiments of two subsequent years. The marker proteins were quantified by ELISA. It was found that the expression of PAT and WGA markedly increased when the wheat was grown in the field compared to that in the greenhouse. There were no significant differences between the WGA contents of the parent and transgenic wheat lines, but a broad range of expression of PAT and WGA was observed in the transgenic lines. PAT did not survive in the small intestine of the rats, while WGA was resistant to digestion in different ratios and was bound to the intestinal epithelium.
It has been proved that because of the different past of the parcels regarding their soil, agronomical and technological parameters, weed sampling results may not be generalised. Therefore it is necessary to study those solutions how to determine on an acceptable confidence level a parcel’s weed infestation with optimised sampling techniques.For studying the question we have delimited on wheat stubble a total sample area of 36×54 metres (using it as reference) and divided it into 2×2 cells giving a total of 486 sample cells. Then we surveyed the weed infestation and GPS recorded the location of each cell.We have analysed the weed infestation data with mathematical and statistical methods comparing the results of cells with each other and with the total sample area. We found that in several cases of different sample cells weed infestation displayed a diverse picture. This way sampling of weeds is extremely difficult.We found close relation between relative frequency of weeds and sampling accuracy. Therefore sampling is reliable only for surveying the frequent weeds in a parcel, while more rarely found weeds (e.g. spots of perennials) are to be scouted only by means of going over the parcel and GPS recording them. Otherwise, in the case of a traditional sampling process, the number of sampling cells required for acceptable reliability is unnecessarily high.Consequently, it is necessary to further study the economic and cost efficiency aspects of the needed weed sample density from the point of view of reasonable sample density, accuracy and optimal yield.
The aim of our study was to investigate the susceptibility of some Chenopodium species (Chenopodium album, C. glaucum, C. berlandieri, C. ugandae) to six viruses (Alfalfa mosaic virus, Cucumber mosaic virus, Obuda pepper virus, Potato virus Y, Sowbane mosaic virus, Zucchini yellow mosaic virus). Fourteen plants of each species were mechanically inoculated and virus susceptibility was evaluated on the basis of symptoms and back inoculation. A series of new host-virus relations were determined.
In this review results are summarized regarding the effect of virus infection on the physiological processes of weeds. Through several host-virus model relations the biomass and seed production, seed viability and germination, nutrient uptake, drought-resistance and photosynthetic pigment content of healthy and virus infected plants were compared. Because of their broad host range and high genetic variability viruses cannot be used for biological weed control. It was concluded that viruses unfavourably can influence physiological processes of weeds. Therefore, they may contribute indirectly to the reduction of competitive ability and population of weeds.
Abstract
Enzymatic hydrolysates of mechanically deboned meat (MDM) for a long time have been used as flavouring and functional food ingredients in the food industry and also as the bases of formula foods for special dietary uses.
The aim of the present study was to produce MDM hypo-antigenic products with improved digestibility and high biological value to be used as a milk protein alternative. turkey MDM was treated with digestive enzymes (trypsin and/or α-chymotrypsin, or pancreatin), followed by freeze drying. The optimised reaction conditions of hydrolysis were at 6% (w/v) of meat protein in 0.1% NaHCO3 buffer, pH 7.5; pancreatin enzyme with 50 TAME units/g meat protein substrate, 37 °C and 60 min). Hydrolysates (MDMH) were assessed for degree of hydrolyses (DH, %) by using trinitrobenzenesulphonic acid method and MW distribution by SDS-PAGE. Modification of immune reactive binding sites in MDMHs was monitored by immunoblot with cow’s milk, chicken egg or meat allergic human patients’ sera. Biological value indices (True Digestibility (TD), Net Protein Utilisation (NPU), Biological Value (BV)) were determined using rat feeding trials. Among the MDMH products, the pancreatic hydrolysate proved to be the most favourable in terms of biological value and digestibility as well as hypoallergenic property.
