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At both national and international levels, increasing attention is paid to the evaluation of the risk of occurrence of veterinary drug residues in foodstuffs and foods of animal origin, and to the introduction of appropriate measures to reduce this risk. The design and strategy of antibiotics and sulphonamide detection in milk involve two different aspects: the ability to sell the milk depending on its quality (technological safety), and the health safety of the milk regulated by the recent legislative regulations (toxicological safety). Veterinary drug residues in milk represent a health risk for the consumer. This review describes the methods used for extensive monitoring of antimicrobial agents - microbial inhibitor methods and rapid specific assays.

Grape skins contain a plenty of different flavonoids, most of them revealing significant antioxidant properties. In this contribution, a complex study is presented of grape skin ethanol extracts, prepared from grape skins of two vine grape varieties, Svatovavřinecké (St. Laurent) and Alibernet. Extracts were prepared from two different amounts of lyophilised grape skin powders using the pressurised fluid extraction (PFE). The antioxidant activity of the extracts was tested by EPR spectroscopy in Fenton system generating reactive radicals (*OH, O^+>) assays. Total phenolic content (TPC) of the individual extracts and their tristimulus colour values (CIE Lab) were evaluated, using an UV-VIS spectrophotometer. All the data obtained were subsequently correlated and discriminated, using the multivariate statistics, involving the canonical discriminant analysis, principal component analysis, and canonical correlation analysis. Results obtained indicated that PFE is a suitable extraction technique, only slightly influencing antioxidant ability as well as composition of the so-prepared extracts. The influence of extraction conditions on the entire monitored characteristics was insignificant.

A total of 20 healthy green iguanas (14 males and six females with body weight ranging from 280 to 720 g) were divided into three groups and used for the experiment. Carprofen (2.0 mg/kg, i.m.) was administered to seven iguanas for 10 days, five were treated with meloxicam (0.2 mg/kg, i.m.) for the same period, and eight iguanas received the same volume of saline solution (0.04 ml/kg). All iguanas were blood sampled on Day 1 and 11 to obtain haematological and biochemical parameters. Comparing the values within particular groups, a decrease in haemoglobin concentration and packed cell volume accompanied by an increase in azurophils (P < 0.05) was observed in iguanas treated with carprofen. Decreased values of haemoglobin and packed cell volume were also found in control iguanas (P < 0.05). Increased ALT levels (P < 0.01) were found in all three groups of iguanas. A decrease in the concentration of Ca (P < 0.01) was observed both in meloxicam-treated iguanas and in the control ones. Mean ALT values of carprofen-treated iguanas (2.42 ± 0.52 μkat/l) were considerably higher (P < 0.01) than those in iguanas treated with meloxicam (0.49 ± 0.18 μkat/l) or saline (0.43 ± 0.13 μkat/l). Repeated doses of carprofen induced higher levels of AST (0.82 ± 0.26 μkat/l) compared with saline (P < 0.01, 0.31 ± 0.16 μkat/l) or meloxicam (P < 0.05, 0.38 ± 0.16 μkat/l). All blood parameters of green iguanas following the 10-day intramuscular administration of both carprofen and meloxicam were within the physiological reference values of this species.within the physiological reference values of this species.

The aim of the present study was to investigate the concentrations of total mercury and methylmercury in muscle of 55 chub (Leuciscus cephalus) from seven main tributaries (Orlice, Chrudimka, Cidlina, Jizera, Vltava, Ohře, Bílina) of the Elbe River and to evaluate the health risks of eating fish from the tributaries monitored. Mercury was determined by means of cold vapour atomic absorption spectrometry using AMA-254, methylmercury in the form of CH₃HgCl by gas chromatography. The highest mean concentrations of total mercury and methylmercury were found in the Jizera (0.27 ± 0.19 mg/kg and 0.23 ± 0.15 mg/kg, respectively) and the lowest mean concentrations of total mercury and methylmercury were found in the chub from the Cidlina (0.07 ± 0.05 mg/kg and 0.06 ± 0.04 mg/kg, respectively). The average methylmercury-to-total mercury ratio was 83 ± 15%. The fish intake hazard indexes calculated for the individual tributaries monitored were between 0.01 and 0.03. The results of this study show that the Elbe River is not significantly affected by mercury contamination from its main tributaries

The gas chromatographic (GC) determination of volatile constituents and the determination of ¹³C/¹²C isotope ratios by isotope ratio mass spectrometry - IRMS analysis as well as SNIF-NMR analysis of (D/H)I and (D/H)II ratios in ethanol are prospective analytical methods which can be used for checking the authenticity of fruit spirits and for detecting their adulteration. Different concentrations of volatile compounds such as acetaldehyde, ethyl acetate, diethyl acetal, methanol, 1-butanol, 2-butanol, 1-propanol, 2-methyl-1-propanol, 2- and 3-methyl-1-butanol, volatile fatty acids and isotopic data were demonstrated using discriminant analysis. The results show that the determination of isotope ratios can be used especially for distinguishing between fruit spirits and others spirits, i.e. those made from beet sugar, maize, cane sugar, grain, potato, or synthetic alcohol. Gas chromatography also makes it possible to discriminate between respective spirits derived from one kind of fruit such as sweet cherry brandy, sour cherry brandy, pear brandy, apple brandy, apricot brandy, or plum brandy.

The content of total anthocyanins was determined in grapes of nine grapevine (Vitis vinifera L.) varieties belonging to the traditional blue vine varieties grown in south Moravia (Czech Republic) within the period of 2002-2007. Factors of vintage and health condition of grapes were observed. The material balance of the colour substances in grapes was related to the dry matter of skins of berries and that of fresh grapes used as raw material for vinification. The highest content of pigments was found in the variety Neronet (2.15-4.49 g/kg of fresh grapes), which belongs to the so-called Teinturier varieties. Besides the variety Neronet (containing 30.6-73.4 mg/g of dry skin), high contents of total anthocyanins in dry skins were found in the varieties Dornfelder (24.7-59.0 mg/g of dry skin) and Cabernet Moravia (20.1-59.3 mg/g of dry skin). In the long run, the lowest concentrations of pigments were determined in grapes of the varieties Blauer Portugieser (0.51-1.02 g/kg of fresh grapes) and Pinot noir (0.27-0.60 g/kg of fresh grapes). The highest colour capacity was found in grapes harvested in the 2003 and 2006. Contents of anthocyanins were significantly lower (P = 0.001) in damaged grapes. Grapes containing more than 40% of rotten berries revealed in skins and whole grapes only 41% and 55%, respectively, of the colour capacity of the healthy raw material.

The aim of our work was to estimate the usefulness of rabbit polyclonal anti-QQQPP peptide antibodies to determination of gluten proteins and the usage of these antibodies to estimate the changes of allergenicity of wheat flour after enzymatic modification. For enzymatic modification of wheat flour trypsin, subtilisin and transglutaminase were used. By the use of rabbit antibodies against QQQPP peptide we have stated that the products of subtilisin and transglutaminase degradation exert strongly decreased immunoreactivity.

Investigations were carried out to assess the efficiency of five plant essential oils: thyme, myrtle, laurel, sage, and orange oils as natural food preservatives. The effect of the plant essential oils against Escherichia coli, Listeria monocytogenes, Staphylococcus aureus and Candida albicans at concentrations of 5-20 µl/disk (diameter 6 mm) and 0.5-3% (v/v) was studied in agar diffusion test medium and milk medium. The essential oils of these extracts exhibited markedly antibacterial and bacteriostatic activity, with thyme showing the highest inhibition and orange the lowest. However, with thyme extract, high inhibitory activity was observed for all tested concentrations, L. monocytogenes showed less sensitivity towards essential oil extracts.

The group of 7 strains of facultatively heterofermentative lactobacilli (FHL) of the non starter lactic acid bacteria (NSLAB) isolated from semi-hard cheeses using a well agar diffusion assay possessed a different level of inhibition activity against 16 different strains of Clostridium sp. belonging to the species Cl. butyricum, Cl. tyrobutyricum, Cl. beijerinckii, and Cl. sporogenes. Two selected strains with the production of partially indentified anticlostridially active inhibitory substances, Lb. paracasei ST68 (producing hydrogen peroxide) and Lb. paracasei 171R2 (producing bacteriocin and hydrogen peroxide), were tested for the inhibition activity against gas producing Cl. butyricum 10702 and Cl. tyrobutyricum 184 in cheese slurry. The effects of both strains were different in reducing the numbers of gas producing Cl. butyricum 10702 by > 3 log cycles and Cl. tyrobutyricum 184 by > 1 log cycles in cheese slurry during the tested storage periods of 24 days at 13°C. The Cl. tyrobutyricum strains isolated from spoiled cheese were identified by species-specific PCR for Cl. tyrobutyricum.

Peanut skins were isolated from deshelled and dried conventional and high-oleic peanuts. In order to obtain simpler mixtures of phenolics with other components of the respective extract, the samples were extracted with solvents of increasing polarity (hexane, ethyl acetate, and methanol). The amounts of extracts were as follows: methanol > hexane > ethyl acetate, and the contents of phenolic constituents in the extracts: ethyl acetate > methanol > hexane. Ethyl acetate extracts from the skins of both conventional and high-oleic peanuts were about the same. The amount of peanut skin ethyl acetate extract was higher than that of tea leaves, but lower than those of Labiatae plants which were also analysed. Antioxidant activities under the conditions of the Schaal Oven Test in lard and in rapeseed oil were only moderate, lower than in the case of synthetic antioxidants (butylated hydroxytoluene, butylated hydroxyanisole, ascorbyl palmitate). The reducing power, free DPP* radical scavenging, inactivation of hydroxylic, and superoxide free radicals were medium, comparable to those of synthetic antioxidants; these activities also resembled to those in the extracts of conventional and high-oleic peanut skins.

Based on NIRS (near infrared reflectance spectroscopy) measurements carried out in a collection of 262 samples of winter oilseed rape with a different content of fatty acids (FA) in oil, calibration equations for the laboratory instrument Foss-NIRSystem 6500 were developed. Calibration was focused on the possibility of screening seed samples of different composition of oleic acid (C18:1), linoleic acid (C18:2) and linolenic acid (C18:3) using NIRS analysis. The reference method was gas chromatography (GC). The content of FA in segregating F₂ generations after crossing between lines with different contents of FA and lines with standard content of FA in oil ranged from 32.3 to 82.0% for C18:1, 10.2-26.8% for C18:2 and 3.3-11.8% for C18:3. The verification of a validation equation in 50 randomly selected samples of F₂ generation in the year 2006 proved high correlation coefficients (r) between NIRS analysis and GC values, r = 0.86 for C18:1, r = 0.82 for C18:2 and r = 0.85 for C18:3. Non-destructive NIRS analysis enables rapid and reliable selection of materials with different composition of FA in the seed of oilseed rape (lines with desirable high content of C18:1 and low content of C18:3).

26 herds with 71 586 individual records were used. We tested a hypothesis that milk efficiency was influenced by the elevation of the farm, housing system, breed, area of altitude, and by the cooling of dairy cows. There were 20 herds from lowlands and 6 herds from mountains, 20 herds from free-stall housing, 6 herds from tie-stall housing. 8 herds consisted of Slovakian Pied cattle, 4 herds of Red Holstein cattle, 11 herds of Black-Pied Lowland cattle and 3 herds of Slovakian Pinzgau cattle. The herds were divided into 4 groups according to the nearest meteorological station, and they were distributed according to the type of cooling. 10 herds were cooled by misting, 16 herds by fans. We recorded from 96 to 117 summer days and from 49 to 63 tropical days in lowlands for this summer period. Ninety days with temperature-humidity index (THI) above 72.0 were found in the lowest-elevation area. During 55 days we recorded the values higher than 78.0. Production of milk was higher in lowlands than in mountains (8 761.4 kg vs. 6 372.0 kg; P < 0.01). Differences were also recorded in the evaluation of fat and protein production (346.0 kg vs. 275.9 kg; P < 0.01; 282.6 kg vs. 205.9 kg; P < 0.001). Milk and protein production was higher in free-stall housing than in tie-stall housing (8 656.3 kg vs. 6 722.1 kg; P < 0.05; 278.7 kg vs. 218.9 kg; P < 0.05). The highest milk production was recorded in Black-Pied Lowland cattle (8 832.7 kg) and the lowest in dairy cows of Slovakian Pinzgau cattle (6 058.0 kg). The mist cooling of dairy cows increased (P < 0.05) the amount of produced milk and protein (9 234.4 kg vs. 7 569.7 kg; 293.5 kg vs. 247.1 kg).

The antioxidant activity of 17 Czech medicinal plants was studied and compared with the antioxidant activity of green tea. The antioxidant activities of water and ethanol extracts of the plants tested were determined by a spectrophotometric method using the stable free radical DPPH (2,2-diphenyl-1-picrylhydrazyl), and further the contents of the compounds with reducing properties in water extracts were determined by flow injection analysis with amperometric detection (using a detection potential +0.7 V). Considerable antioxidant activities were found in the extracts of plants from the Rosaceae family (rosehips and leaves of raspberry, blackberry, and strawberry), the Lamiaceae family (oregano, sweet balm, thyme, dead-nettle, and mint), and flowers of linden and elder.

Farmers in rural areas of almost all the districts of Bangladesh cultivate different varieties of edible plant karela to satisfy nutritional requirements. Herein, we report on the characteristics of seed oils and nutrients and mineral contents of seeds from three varieties of karela. Most of the physicochemical characteristics were significantly (P < 0.05) affected with the samples tested. Seed oils of all varieties displayed a higher degree of unsaturation and in GLC reported herein, only five fatty acids were identified. The profiles of fatty acid composition were not wholly similar in all varieties in which unsaturated fatty acids represented more than 72%, α-eleostearic acid having been detected in the amount of 50.36-53.22%. Acylglycerol classes were estimated to be monoacylglycerols (1.18-2.01%), diacylglycerols (1.83-2.98%), and triacylglycerols (91.11-93.03%) whereas lipid classes included neutral lipids (86.83-91.09%), glycolipids (4.37-7.43%), and phospholipids (3.22-4.62%). Of the major energy producing nutrients, all varieties contained large amounts of lipid (33.93-36.21%) and protein (18.23-21.36%), and potentially useful amounts of calcium (383.45-440.96 μg/g), iron (41.10-45.03 μg/g), and other essential minerals. The nutrient information presented in this report should stimulate the local public health authorities in Bangladesh to consider the question of recommending the vegetable karela to be consumed by adults and children alike in Bangladesh, including pregnant women and others with higher than normal nutritional requirements.

A high seed vigour is a desired trait in agronomy as it promotes the fast field emergence and homogeneity of harvest, which is necessary for producing quality food raw material. In this work, we studied the effects of the seed vigour on the bread quality. Relationships between the grain vigour, nutrients and anti-nutrients, contents, and bread volume were evaluated using the samples acquired from official variety trials. In the trials, the grain vigour was perceived as the grain ability to germinate in stress conditions, i.e. at 10°C in a solution of polyethylene glycol (PEG 6000 at osmotic pressure - 2 bars, the so called permanent wilting point). The results showed that the locations and years changed the bread volume but not the rank of the varieties tested in the trait. A higher grain vigour was significantly related to a higher falling number during two of the three trial years. The vigour was negatively related to the lipase activity. Moreover, other decomposing enzymes showed a similar tendency as was that found in the samples with the most diverse vigour. The grain samples with 80-90% vigour produced the greatest bread volume. The grain with a vigour below or above this range produced less voluminous loaves. The varieties of the highest quality produced the most voluminous bread from the samples reaching the grain vigour of 90-95%. The standard germination test was not related to the vigour and was less responsible for the bread quality. High-quality varieties had higher contents of total polyphenols than the varieties of lower quality, and the polyphenol content was correlated with the vigour (r

Technical information and data on the physical and mechanical properties of agricultural and animal products are necessary to design various equipments for agriculture and industry. In this study some physical properties such as mass, length, diameter, geometric mean diameter, surface area, sphericity, volume, coefficient of friction and packaging coefficient were determined for Japanese quail eggs. Furthermore, the mechanical behaviour of Japanese quail eggs was determined in terms of average rupture force, deformation and toughness (energy absorbed by the Japanese quail eggs per unit volume). Egg samples were compressed along their X and Z-axes. The average values of their mass, length, width, shell thickness, geometric mean diameter, surface area, sphericity, volume and packaging coefficient were measured to be 12.69 g, 34.87 mm, 26.20 mm, 0.27 mm, 28.82 mm, 2 608.5 mm², 1.10, 359.17 mm³, 0.469, respectively. The values of the coefficient of friction for quail eggs on the surfaces of plywood, glass, galvanized steel and fibreglass were 0.301, 0.282, 0.274 and 0.266, respectively. The highest rupture force, deformation and toughness were obtained when Japanese quail eggs were loaded along their X-axis. Compression along the Z-axis required the least compressive force to break the eggs as compared to the other compression axes. Rupture force, deformation, absorbed energy and toughness for the X-front axis were determined to be 10.51 N, 1.5 mm, 7.88 Nmm and 0.219 Mj/mm², respectively.

Bovine tuberculosis was last detected in cattle and pigs in the CzechRepublicin 1995. Since March, 31, 2004(Commission Decision No. 2004/320/EC) the Czech Republichas been included amongst states free from bovine tuberculosis within the European Union. The purpose of the present study was to evaluate results of intravital and post-mortem diagnosis of mycobacterial infections in slaughtered cattle and pigs from 2000 to 2004. When bovine tuberculosis in cattle was investigated, a tuberculin skin test with bovine tuberculin was performed every year and a skin test with avian tuberculin was simultaneously conducted in the animals with a positive response. A total of 2 419 889 animals were examined with a positive response being found in 123 (0.005%) of them. After slaughter, bovine tuberculosis was not detected in any of these animals by gross and/or laboratory examinations. With avian tuberculin, 40 349 animals were tested and positive responses were detected in 43 (0.1%) of them; the incidence was similar in all the years monitored. Tuberculous lesions were detected in 209 (0.01%) of 1 967 211 slaughtered cattle. Mycobacteria were present in 40 (21.3%) of 188 animals examined by laboratory methods: 26 isolates of Mycobacterium avium subsp. avium (18 isolates of serotype 2 and 8 isolates not typeable), 11 isolates of M. a. hominissuis (1 isolate of serotype 8 and 10 isolates not typeable), and 3 isolates of atypical mycobacteria. Tuberculous lesions were detected in 49 312 (0.22%) of 22 312 580 slaughtered pigs by veterinary-meat inspection. During the 5-year-period monitored, the incidence of tuberculous lesions decreased from 0.37% in 2000 to 0.10% in 2004. The following mycobacteria were isolated from 757 (33.5%) of 2 261 animals whose organs were examined by culture: 203 isolates of M. a. avium (180 isolates of serotype 2, 3 isolates of serotype 2/8, and 20 isolates not typeable), 442 isolates of M. a. hominissuis (1 isolate of serotype 1, 262 isolates of serotype 8, 35 isolates of serotype 9, 1 isolates of mixed serotypes 8/9, and 143 isolates not typeable), and atypical mycobacteria (n = 112). In both animal species, M. avium complex members prevailed: M. a. avium was the most prevalent subspecies in cattle, M. a. hominissuis in pigs. The main sources of M. a. avium and M. a. hominissuis are free living birds and contaminated external and stable environments (i.e. drinking water, feeds, and feed supplements), respectively. During the entire period monitored, miliary or generalized tuberculosis was not detected in any of the animals. The decreased incidence of tuberculous lesions in pigs was particularly a result of preventive measures adopted to control the occurrence of atypical mycobacteria.

Coenzyme Q₁₀ is an important mitochondrial redox component and endogenously produced lipid-soluble antioxidant of the human organism. It plays a crucial role in the generation of cellular energy, enhances the immune system, and acts as a free radical scavenger. Ageing, poor eating habits, stress, and infection - they all affect the organism's ability to provide adequate amounts of CoQ₁₀. After the age of about 35, the organism begins to lose the ability to synthesise CoQ₁₀ from food and its deficiency develops. Many researches suggest that using CoQ₁₀ supplements alone or in combination with other nutritional supplements may help maintain health of elderly people or treat some of the health problems or diseases. Due to these functions, CoQ₁₀ finds its application in different commercial branches such as food, cosmetic, or pharmaceutical industries. This review article gives a survey of the history, chemical and physical properties, biochemistry and antioxidant activity of CoQ₁₀ in the human organism. It discusses levels of CoQ₁₀ in the organisms of healthy people, stressed people, and patients with various diseases. This paper shows the distribution and contents of two ubiquinones in foods, especially in several kinds of grapes, the benefits of CoQ₁₀ as nutritional and topical supplements and its therapeutic applications in various diseases.

Volatile aroma compounds production by two autochthonous Saccharomyces cerevisiae strains, isolated from Istria region, and three other yeast strains (Saccharomyces bayanus and two commercial Saccharomyces cerevisiae wine yeasts) was investigated on a small scale using synthetic VP4 medium and Graševina must at 12 and 20°C. The results obtained by gas chromatography analyses were compared with the aroma production properties of the native microflora, remaining after Graševina must sulphiting. In both media and at both temperatures, the wine yeasts investigated showed different metabolic profiles regarding the tested volatile aroma compounds, which should be taken in consideration for autochthonous wine production. Although the synthetic medium proved to be appropriate for the investigation of the fermentative properties, the determination of secondary aroma production by wine yeasts has to be conducted by must fermentation or possibly by fermentation of another synthetic medium whose composition would be more similar to must.

The occurrence and content of some polyphenols and the antioxidant activity of compounds present in grape berries, stems and leaves of Vitis vinifera L. were evaluated. Three white and three blue varieties of grapevine were investigated. The contents were determined of trans-resveratrol, trans-piceid, caftaric acid, tryptophan, catechin, epicatechin, total polyphenols, and flavanols, both in healthy material and in the samples of the plant material infested with microorganisms (Botryotinia fuckeliana Whetzel anamorph Botrytis cinerea Pers.; Uncinula necator (Schw.) Burr; Plasmopara viticola (Berk. & M.A. Curtis) Berl & De Toni). The antioxidant activity of the extracts obtained was determined by different methods: FRAP (Ferric Reducing Antioxidant Power), DPPH (2,2-diphenyl-1-picrylhydrazyl radical) and TAC-PCL (Total Antioxidant Capacity of Photochemiluminescence). The content of trans-resveratrol varied between 0.3-2.3 mg/kg and 0.7-12.1 mg/kg in non-infested and infested grape berries, respectively. The content of trans-piceid between 0.6-2.9 mg/kg and 1.5-6.3 mg/kg in non-infested and infested grape berries, respectively. The content of trans-resveratrol varied between 2.5-10.3 mg/kg and 3.7-20.9 mg/kg in healthy and in infected leaves, respectively. The content trans-piceid varied between 11.3-58.4 mg/kg and 18.5-60.9 mg/kg in the healthy and in the infected leaves, respectively. The highest content of trans-resveratrol was found in stems (16.3-276.3 mg/kg). In young lateral shoots, the highest levels of trans-piceid (12.6-99.7 mg/kg) and caftaric acid (474-2257 mg/kg) were determined. The infested grape berries showed a higher antioxidant activity, which was most closely correlated with the content of total polyphenols (correlation coefficient = 0.8336-0.9952).

The growth and yield response of spring wheat to inoculation with foreign and local rhizobacteria of Erzurum (Turkey) origin was studied. At the first stage of the research, a greenhouse experiment was carried out with wheat cv. Kirik using 75 local bacterial strains isolated from the soil with 6 foreign bacteria, and a control. According to results of the greenhouse experiment 9 local strains were identified. At the second stage, the response of wheat cv. Kirik to 20 treatments (9 local strains, 6 foreign bacteria, 4 levels of N, and a control) was investigated in Erzurum field conditions. Seventeen strains had significant positive effects on tiller number per plant, 47 strains on plant height, one strain on dry matter yield, and 28 strains on plant protein content in the greenhouse experiment. Inoculation with certain rhizobacteria clearly benefited growth and increased the grain and N-yield of field grown wheat. The effects of local strains were observed to be in general superior to those of foreign strains. Inoculation with the local Strain No. 19, 73, and 82 increased total biomass by 18.7, 18.1, and 19.9%; grain yield by 18.6, 17.7, and 18.0%; total N-yield by 27.5, 24.3 and 26.0%, respectively, as compared to control. In conclusion, Strain No. 19, 73, and 82 can be a suitable biofertilizer for spring wheat cultivation in areas with similar conditions as in Erzurum. Inoculation with these strains may lead both to increases in wheat yield and savings of nitrogen fertilizer.

Between 2002 and 2004 the evaluation method of resistance to common scab was tested on potato genetic resources. The resistance of potato tubers to common scab was evaluated in the greenhouse provocation tests with planting in naturally infested soil. The test was evaluated on the tubers of 26 varieties and hybrids of Solanum tuberosum derived from a potato genetic resource collection. Ten tubers of each sample were individually planted into three-liter pots containing infested soil. Analysis of variance confirmed significant differences among individual varieties and hybrids as well as among the years. A rating scale for the evaluation of resistance to common scab was designed. The genotypes ranked into scores 7 (high resistance) to 9 (very high resistance); on the new scale they could be considered perspective genetic resources in breeding for improvement of the level of this character. The evaluated set consisted of genotypes: Samantana, Karin, Monika, Impala, Santé, Annabelle, YP 94-067, YP 91-123, BEE J 85, Viola, and Granola.

The effect of the length and intensity of feed restriction on carcass quality characteristics was studied in two experiments. In the first experiment rabbits were restricted 1 or 3 weeks. Group 1 was fed ad libitum, group 2 was restricted from 35 to 42 days of age (50 g per day/rabbit), group 3 was restricted from 42 to 49 days of age (65 g per day/rabbit), group 4 was restricted from 56 to 63 days of age (90 g per day/rabbit) and group 5 was restricted three weeks, from 35 to 42 days of age (50 g per day/rabbit), 42 to 49 days of age (65 g per day/rabbit) and from 56 to 63 days of age (90 g per day/rabbit). Rabbits were slaughtered at the age of 84 days. In the second experiment the rabbits were restricted between 42 and 56 days of age and the rabbits were divided into three groups. Group 1 was fed ad libitum, the rabbits in group 2 got 50 g of feed at the age of 42 to 49 days and 65 g of feed at the age of 49 to 56 days and in group 3, 50 g and 75 g of feed in the two periods, respectively. Carcass characteristics were evaluated at the age of 49, 56, 63 and 84 days. Restriction did not affect dressing percentage but reduced the weight of loin. Renal fat was detected in restricted rabbits at the age of 63 days whereas in the ad libitum fed ones at 56 days. Renal fat was significantly (P ≤ 0.05) reduced in rabbits restricted from 56 days of age (experiment 1, 19.71 g, 19.28 g, 26 g vs. 14.33 g and 11.43 g). Kidney and liver weight was influenced by the restriction and realimentation period. The meat colour and pH (measured 24 h post mortem) were not affected by treatments.

HPLC method for 5-methyltetrahydrofolate (5-MTHF) determination in vegetables was optimised for the folate release from the food matrix. Enzymatic hydrolyses using the subsequent addition of α-amylase, protease, and conjugase from hog kidney, or their combinations, were tested. The highest release values were obtained with the application of enzymes α-amylase and conjugase, amounting to 112.4-127.0% of the values obtained in the processing with sole conjugase. The simultaneous addition of both enzymes and the incubation at pH 4.9 did not suppress the release of folates. Spinach, Chinese cabbage, lettuce, cauliflower, and broccoli contained more than 50 μg of 5-MTHF/100g, whereas less than 25 μg/100 g was found in potatoes, carrot, white cabbage, green and yellow pepper. Individual vegetables differed in the folate retention during their boiling under constant conditions. The highest retention was found in Brussels sprouts, cauliflower, and broccoli. After 8 min boiling more than 75% of the initial amount of 5-MTHF remained in these vegetables. Lower values of 5-MTHF retention, between 37% and 52% of their initial content, were found in spinach, savoy cabbage, and carrot.

The effect of carbon monoxide was studied on the colour stabilisation of minced meat and on oxidation of lipids. The meat colour was evaluated using reflectance spectrophotometry and video image analysis (software LUCIA 5.20). Minced meat (beef and mixture of beef and pork) was packed under industrial conditions into three different modified atmospheres (MA) consisting of combinations of oxygen, carbon dioxide, carbon monoxide, and nitrogen. Carbon monoxide prevented the oxidation of lipids and haem pigments in minced meat and thus stabilised the red colour of minced meat. The redness a* of the meat packed under CO was constant during storage (nearly a* = 20), whereas in MA containing oxygen this value decreased (a* = 5). The thiobarbituric acid reactant substances content rose in the samples packed under MA to 2 mg/kg, whereas in CO atmosphere it did not exceed 0.1 mg/kg.

FT-IR spectra were recorded of Escherichia coli cell mass with the aim of obtaining spectral traits possibly useful in a rapid detection and characterisation of this indicator bacterium. A well differentiated spectrum was obtained from the cell mass harvested in a stationary phase of growth, e.g., after 24 h, from a minimum nutrient broth. The cell mass, harvested either earlier or grown in nutrient solutions which contained an enhanced carbon or nitrogen concentrations delivered somewhat different IR spectra, apparently due to a higher content of nucleic acid components as related to other structural constituents of bacterial cells. Consequently, the FT-IR spectra of E. coli, although rather rapidly to collect, seem only capable of delivering useful and reproducible information if the cell mass is obtained under standardised cultural conditions.

Enzymes with high specific activities at low temperatures have potential uses in the food industry. Cold-adapted microorganisms are potentially useful sources of cold-active enzyme. To find cold-adapted β-galactosidase, we isolated several cold-adapted microorganisms from glacier zone soil. One cold-adapted β-galactosidase producing strain was obtained. The biochemical characteristics and the results of 16S rDNA sequencing identified the strain as Rahnella aquatilis. The enzyme was purified by column chromatography after which a single protein band migrating near 60 kDa was observed by means of SDS-PAGE. The β-galactosidase was optimally active at 35°C and at pH 6.5 when assayed with o-nitrophenyl-β-D-galactopyrano-side as substrate. The enzyme activity was sensitive to temperatures above 40°C and was undetectable at 45°C. Metal ions Mn²⁺and K⁺ activated the enzyme while Cu²⁺, Zn²⁺, Fe³⁺, and Al³⁺ inhibited the activity. The enzyme was also assayed for lactose hydrolysis. When milk is treated with the enzyme at 30°C for 2 h, the degree of lactose hydrolysis can reach 80%. It has, thus, potential applications in the food industry.

The inhibition of mutagenicity was assessed by Ames test by bacterial strains Salmonella typhimurium TA98 and TA100 using two mutagens and methanolic extracts of healthy fresh berries of blue grapevine varieties - St. Laurent, Portugal, André and white varieties - Chardonnay, Welschriesling, Pinot Gris and berries infected with Botrytis cinerea fungus. As model mutagens, two compounds whose presence in food is real, 2-amino-3-methyl-3H-imidazo-(4.5-f-)-quinoline (IQ), arising from certain heat treatments of meat and acting as indirect mutagen after metabolic activation, and N-nitroso-N-methylurea (MNU) acting as a direct mutagen, were applied. An increased risk of MNU is due to its possible endogenous formation. Fermentation sediment after vinification of the varieties Chardonnay, Welschriesling and André was tested by similar experimental system. All extracts showed strong positive inhibition of mutagenicity, berries infested with Botrytis cinerea also in diluted extracts. Positive inhibition was demonstrated also by fermentation sludge.

This review article is a part of the survey of the generally accepted biosynthetic pathways that lead to the most important natural pigments in organisms closely related to foods and feeds. The biosynthetic pathways leading to xanthones, flavonoids, carotenoids, and some minor pigments are described including the enzymes involved and reaction schemes with detailed mechanisms.

The effects of the pressing technology and clarification of white grape musts on concentrations of phenolic compounds and their antioxidative capacity were investigated. Four different varieties were processed by hydraulic or pneumatic pressing technologies. In the individual stages of pressing and after the application of different doses of the clarification agent, must samples were analysed for the content of polyphenols and the antioxidative capacity. The highest concentrations of caftaric acid were estimated in the musts made by hydraulic pressing from grapes of Welschriesling variety. On the other hand, musts made from grapes of Grüner Veltliner showed the highest contents of trans-piceid in both variants of pressing. The values of antioxidative capacity of the must samples analysed were not significantly different. The influence of clarification on the changes of phenolic substances in young red wines of Saint Laurent variety was also studied. Six various clarifiers were tested as applied in two different doses. Polyvinylpolypyrrolidone caused the highest losses of trans-resveratrol in the course of red wine clarification. The concentrations of catechin, epicatechin, and total anthocyanins as well as the colour parameters of red wines were influenced at most by the application of egg white.