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11.
Lopparelli RM Cardazzo B Balzan S Giaccone V Novelli E 《Journal of agricultural and food chemistry》2007,55(9):3429-3434
Mozzarella cheese obtained from buffalo (Bubalus bubalis) milk is a typical Italian product certificated by means of the European Protected Designation of Origin (PDO). Mozzarella cheese can also be obtained from bovine milk or bovine/buffalo milk mixtures, but in this case, it cannot be sold as PDO product, and its label must report the actual ingredients. However, bovine milk in PDO products was frequently detected in the past, suggesting fraudulent addition or accidental contamination. Several methods based on end-point polymerase chain reaction (PCR) have been profitably applied in a large number of tests to detect the presence of undeclared ingredients, also in dairy products. In the present study we report a real-time PCR method able to quantify bovine milk addition to pure buffalo cheese products. We validated a normalized procedure based on two targets: bovine mitochondrial cytochrome b (cyt b) to detect and quantify the bovine DNA and nuclear growth hormone (GH) gene used as a universal reference marker. With the use of this real-time PCR assay, 64 commercial mozzarella di bufala cheese samples purchased at local supermarkets, dairy shops, or directly from cheese manufacturers were analyzed. The results obtained demonstrate that most of the commercial samples were contaminated with bovine milk. Therefore, this assay could be conveniently employed to carry out routine and accurate controls aimed not only to discourage any fraudulent behavior but also to reduce risks for consumer health. 相似文献
12.
Celli N Dragani LK Murzilli S Pagliani T Poggi A 《Journal of agricultural and food chemistry》2007,55(9):3398-3407
The in vitro biochemical stability of caffeic acid phenethyl ester in rat and human plasma was investigated and compared with the stability of other caffeic acid esters (chlorogenic acid and rosmarinic acid). The incubation of the compounds in rat plasma for up to 6 h showed that caffeic acid phenethyl ester, but not the other compounds, was hydrolyzed, whereas human plasma did not affect the stability of all the assayed compounds. The products in rat plasma were caffeic acid and an unknown compound, which was identified by mass spectrometry as caffeic acid ethyl ester, produced by transesterification in the presence of ethanol used as vehicle for standard compounds. Specific inhibitors of different plasma esterases allowed the identification of a carboxylesterase as the enzyme involved in the metabolism of caffeic acid phenethyl ester. The oral administration in rats of caffeic acid phenethyl ester in the presence of both ethanol and 2-(2-ethoxyethoxy)ethanol gave rise to a dramatic increase of caffeic acid, as well as low levels of caffeic acid phenethyl ester, caffeic acid ethyl ester, and caffeic acid 2-(2-ethoxyethoxy)ethyl ester, in urine collected within 24 h after treatment. These results suggest that caffeic acid phenethyl ester is hydrolyzed also in vivo to caffeic acid as the major metabolite and that its biological activities should be more properly assayed and compared with those of caffeic acid, its bioactive hydrolysis product. Moreover, alcohols should be carefully used in vivo as solvents for caffeic acid phenethyl ester, since they can give rise to new bioactive caffeic acid esters. 相似文献
13.
Nigro Domenica Giove Stefania L. Colasuonno Pasqualina de Pinto Roberta Marcotuli Ilaria Gadaleta Agata 《Genetic Resources and Crop Evolution》2022,69(6):2191-2202
Genetic Resources and Crop Evolution - Durum wheat (T. turgidum L. var. durum) is one of the most widely cultivated cereal crop in the Mediterranean area. Its production has been triggered by... 相似文献
14.
Oliana Carnevali Maria Claudia Zamponi Roberto Sulpizio Arianna Rollo Miria Nardi Carla Orpianesi Stefania Silvi Massimo Caggiano Alberta Maria Polzonetti Alberto Cresci 《Aquaculture International》2004,12(4-5):377-386
Two bacterial strains Lactobacillus fructivorans (AS17B), isolated from adult sea bream (Sparus aurata) gut, and Lactobacillus plantarum (906), isolated from human faeces, were administered contemporaneously, during sea bream development using Brachionus plicatilis and/or Artemia salina and dry feed as vectors. The probiotic treatment influenced gut colonization: at 35 days post-hatching (p.h.) L. fructivorans was not present in the gut, but the treatment induced colonization by L. plantarum. At 66 days p.h., L. fructivorans was evident also in the control; moreover, when suitable environmental conditions appeared in the post-metamorphosis gastro-intestinal tract, competition between L. plantarum and L. fructivorans occurred. At 90 days p.h., L. plantarum was displaced by L. fructivorans that became significantly higher with respect to the control. In treated groups, probiotic administration significantly decreased larvae and fry mortality. 相似文献
15.
Effect of triploidy on quality traits of shi drum (Umbrina cirrosa L.) until the second rearing year
Severino Segato Luca Fasolato Daniela Bertotto Angelo Libertini Stefania Balzan Adolfo Corato & Enrico Novelli 《Aquaculture Research》2007,38(1):59-65
Carcass and flesh morphometric, reological and chemical traits of triploid (3n) and diploid (2n) shi drum (Umbrina cirrosa L.) were evaluated through 7 months. Three age groups, 17‐, 21‐ and 24‐month‐old fish, were investigated. The effects of ploidy were statistically evaluated and the weight of fish was included in the model as a covariate because triploids grew less than diploids. As expected, fish weight was found to be significantly correlated with all the investigated morphometric traits, but showed a negative correlation with some chemical (pH) and colour traits (lightness) of raw fillet. In comparison with controls, triploid shi drums were characterized by different morphological traits that involved a slender body shape. In triploids, a reduction in condition factor, backbone weight, dressing index and an increase in the agility index were also recorded. When the commercial size (i.e. over 300 g) was achieved, triploids exhibited larger coelomatic and fillet (dorsal white muscle) fat deposition than diploids. Among reological traits, colour and texture were affected by ploidy; raw fillet lightness and cooked flesh tenderness were higher among triploids in all the investigated age groups. As fish were fed with a restricted feeding regimen, fillet fat deposition was supposed to be limited. Thus, the effects of ploidy on reological traits may be only partially explained by lipid fillet amount and are supposed to be more related to different fibre muscle architecture. 相似文献
16.
Haitham Sayed Gunter Backes Hamed Kayyal Amor Yahyaoui Salvatore Ceccarelli Stefania Grando Ahmad Jahoor Michael Baum 《Euphytica》2004,135(2):225-228
A partial genetic linkage map was constructed on 71 doubled-haploid lines derived from a cross between the barley lines Tadmor
and WI2291 with 181 molecular markers. The segregating population was used to detect markers linked to the gene Mlg conferring resistance to powdery mildew (Erysiphe graminis f. sp. hordei) and to genes for quantitative resistance to scald (Rhynchosporium secalis). The gene Mlg on chromosome 4H was flanked by two AFLP markers at a distance of 2.0 and 2.4 cM, respectively. QTLs for resistance to scald
were detected on chromosomes 2H and 3H. This association of molecular markers with qualitative and quantitative disease resistance
loci represents a valuable starting-point for marker-assisted selection.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
17.
Summary The paper addresses the general question of identifying the optimum environment for selection in plant breeding programs for low input agricultural systems. After defining low-yielding and high-yielding environments based on the average grain yield of large numbers of barley genotypes in different cropping seasons, we examined: 1) the phenotypic relationships between the highest yielding genotypes in low- and high-yielding environments, and 2) the genetic correlation coefficients between grain yield in low- and high-yielding environments. The results indicate that the alleles controlling high grain yield in low-yielding conditions are at least partially different from those controlling high grain yield in high-yielding conditions. Therefore, selection in high-yielding environments is expected to produce a negative response or no response in low-yielding environments. This may explain why crop varieties bred under high-yielding conditions failed to have an impact in low-yielding agricultural systems. The results may be extrapolated to systems where environmental concern suggests a reduction of inputs by raising the question of whether crop breeding programs based on selection under high inputs are likely to generate the right type of germplasm for an environmentally friendly agriculture. 相似文献
18.
Summary Groups of 10 barley genotypes were selected for high grain yield under either high yielding (two groups) or low yielding conditions (two groups). The genotypes had a similar average grain yield across a wide range of yielding conditions, but differed in their linear response over environments (environmental sensitivity). The genotypes selected for high grain yield under low yielding conditions were less sensitive to changing environments than genotypes selected for high grain yield under high yielding conditions. The higher stability of genotypes selected under low yielding conditions was shown by both the linear regression analysis and the comparison of coefficients of variation. The use of a safety-first index showed that the probability of a crop failure of genotypes selected for high grain yield under high yielding conditions was between 1.8 and 2.7 times higher than for genotypes selected for high grain yield under low yielding conditions. The development of new cultivars for areas where a large proportion of the crop is grown by subsistence farmers should therefore be based on selection under low yielding conditions. 相似文献
19.
The antioxidizing potency of phenol compounds contained in olive oil mill wastewater (OOMWW) has been elucidated. Commercially available phenol standards at varying concentrations and the Rancimat oxidation test have been used. Refined purified olive oil was utilized as an oxidation lipid substrate. Synthetic antioxidants, such as 2,3-tert-butyl-4-hydroxyanisole (BHA), 3,5-di-tert-butyl-4-hydroxytoluene (BHT), l-ascorbic acid, and gallates (commonly used as food preservatives), and other known chemicals endowed with antioxidizing properties have been employed as reference compounds. The OOMWW phenol compounds have been classified into different groups depending on their antioxidizing potency. This was significantly affected by the tested concentrations of the standards. Mixtures of phenol standards and other antioxidants (l-proline, chlorophyll a, chlorophyll b, and alpha-, gamma-, and delta-tocopherol) have also been tested. Many phenol compounds present in OOMWW showed antioxidizing potency higher compared to that of the less safe synthetic antioxidants and could therefore replace these in the industrial preservation of food items. They could also be used in combination with other natural antioxidants (e.g., tocopherols). In fact, some mixtures of antioxidants, owing also to the synergistic phenomena, showed strong antioxidizing potency. 相似文献
20.
Antonietta?FiorettoEmail author Stefania?Papa Amodio?Fuggi 《Biology and Fertility of Soils》2003,39(1):37-44
Annual production of litter by Cistus incanus (L.) and Myrtus communis (L.) and decomposition dynamics of leaf litter of these species was studied in a Mediterranean shrubland. Myrtus and Cistus produced 472 and 429 g dry weight litter m-2 year-1, respectively. Leaves were the predominant litter component for both species. The average decay constant of Myrtus and Cistus litters enclosed in litter bags, calculated over the whole study period (38 months), was 0.71 year-1 and 0.31 year-1 respectively. In green leaves the N content differed during growth seasons for both species, whereas the content of Ca, Mg, P, K, and Na did not show significant changes. Abscised leaves had lower N, P and K contents than green leaves, evidencing that a nutrient translocation before abscission occurred from senescent leaves. The nutrient contents of the leaves at abscission time, generally higher in Cistus than in Myrtus, allowed us to estimate the annual nutrient input to the soil. Phosphorus and K more than N were rapidly released by the decomposing litters after exposure. Nutrient limitation, in particular P, might be considered the main growth limiting factor for Myrtus and Cistus. Both species were adapted to recovery and rapidly recycle P more than N and K in the living biomass through retranslocation from green leaves before abscission and/or a high release rate from the decomposing litter. The former strategy was better used by Cistus, the latter by Myrtus. 相似文献