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61.
An ethno-pharmacognostic survey was carried out in one of the smallest ethnic and linguistic groups in Europe: the Istro-Romanians of the village of Zejane (in Croatia), which has a population of approximately 140 persons, mainly elderly. Using an intensive field participant observation methodology, we recorded about 60 remedies of the local folk pharmacopoeia, and mainly derived from plants. Among them, the uncommon traditions to use homemade vinegar from wild apple (Malus sylvestris) and Cornelian cherries (Cornus mas) for diverse medical purposes, and houseleek (Sempervivum tectorum) against ear pains have been briefly discussed.  相似文献   
62.
DNA analysis enables genome fingerprinting with consequent identification of different individuals. In the agro-food industry, this can have interesting applications for the identification of species and cultivars of both raw materials and processed food. In this investigation, the efficiency of DNA microsatellite analysis in identifying virgin olive oils from different cultivars was evaluated. Ten virgin oils were obtained in the laboratory from olives of 10 different cultivars and the DNA extracted from the cell residues, recovered by oil centrifugation, was used as a template with seven different primer pairs of microsatellite sequences. The electrophoretic patterns showed an adequate level of amplification and were identical to those obtained from leaves and drupes of the same cultivar. By analyzing all the patterns obtained, the smallest number of microsatellites able to distinguish the examined oils was established and an identification key for the different oils was developed.  相似文献   
63.
Thermal degradation studies of food melanoidins   总被引:1,自引:0,他引:1  
Food melanoidins were isolated from bread crust, coffee, and tomato sauce and their composition was investigated by thermal degradation. Among the generated volatiles, important food flavor compounds were detected: in particular furans, carbonyl compounds, 1,3-dioxolanes, pyrroles, pyrazines, pyridines, thiophenes, and phenols. The results indicated that the isolated melanoidin fractions mainly consisted of compounds formed from carbohydrates and their degradation products. Besides proteins, other food constituents were incorporated in the melanoidin structure as well, such as lipid oxidation products in tomato melanoidins and phenolic compounds in coffee melanoidins. A comparison of the thermal generation of volatiles between these food-derived melanoidins and model melanoidins prepared from a single carbonyl compound and an amino acid showed that the degradation pattern of food melanoidins is quite different from that obtained from a glucose-glycine model system.  相似文献   
64.
Water, Air, & Soil Pollution - Phytotoxicity of Flumequine (F) on the aquatic duckweed, Lemna minor L., and plant drug uptake were evaluated by a simple ecotoxicological test. Flumequine, at...  相似文献   
65.
To identify membrane components of CER cells interacting with vesicular stomatitis virus (VSV) during fusion at acidic pH (fusion from without, FFWO) two different approaches have been used, i.e. (i) treating the whole cells with enzymes and (ii) testing the ability of isolated membrane molecules to interfere with FFWO. Phospholipase A2 and C digestion of cells greatly reduced syncytia formation, pointing towards the involvement of lipid structures as target sites for VSV. Cell susceptibility to FFWO was also reduced after neuraminidase, β-galactosidase or periodate treatment, suggesting that carbohydrate residues may participate in a complex receptor structure required for virus fusion. When membrane molecules were examined separately for their ability to inhibit viral FFWO, phosphatidylserine, phosphatidylinositol, sphingomyelin, cholesterol and GM3 ganglioside were found to be active, confirming the role of membrane lipid moiety in the cell surface structures involved in the early phases of VSV infection.  相似文献   
66.
As a key element of the 'farm-to-fork' approach, an assessment of the safety of feed components should consider major long-term toxicological hazards, such as endocrine disrupting chemicals (EDCs). In this review, attention is given to endocrine-modulating trace elements (such as iodine and trivalent chromium) and their potentially sensitive subgroups as nutritional feed additives from the standpoint of farm animal safety and consumer exposure. Feedstuffs can be a major vehicle for persistent EDCs, such as polychlorinated biphenyls, and potential risks include fish farming and ruminants grazing in polluted areas. Limited data still exist on the feed-to-food transfer of other EDCs, such as brominated flame retardants. EDCs of vegetable origin (e.g. zearalenone and isothiocyanates) can have a greater adverse impact on farm animals than environmental xenobiotics but the risk of carry-over to consumers appears low. Topics for further research are suggested, including the need for more refined exposure data, characterization of biomarkers for long-term effects, xenobiotic-nutrient interactions and the search for novel feed ingredients that are less vulnerable to contamination.  相似文献   
67.
An investigation was carried out into the recovery from calf faeces of Bacillus coagulans spores added to the feed as probiotic. For this purpose, Bacillus coagulans spores (9 log10 CFU g?1) were given daily to 10 calves during the whole farming periods; another 10 calves acted as controls. Throughout the trial the faecal spore counts were significantly (P?<?0.01) higher in the treated group than in the controls (averaging 2.1?×?105 vs 3.7?×?104?CFU g?1). Bacterial cells were recovered from faecal samples and ribotyping matched the strain isolated from faecal sample to the clone administered to the animals. In addition, the recovered cells were found to maintain their functionality aspects of acid production, survival in artificial gastric juice and in the presence of bile, and attachment to human intestinal epithelial cells. The results further elucidate the fate of spore formers administered to calves, and this will help in the development of new species-specific nutritional strategies.  相似文献   
68.
The importance of honey has been recently increased because of its nutrient and therapeutic effects, but the adulteration of honey in terms of botanical origin has increased, too. The floral origin of honeys is usually determined using melisso-palynological analysis and organoleptic characteristics, but the application of these techniques requires some expertise. A number of papers have confirmed the possibility of characterizing honey samples by selected chemical parameters. In this study high-resolution nuclear magnetic resonance (HR-NMR) and multivariate statistical analysis methods were used to identify and classify honeys of five different floral sources. The 71 honey samples (robinia, chestnut, citrus, eucalyptus, polyfloral) were analyzed by HR-NMR using both 1H NMR and heteronuclear multiple bond correlation spectroscopy (HMBC). Spectral data were analyzed by application of unsupervised and supervised pattern recognition and multivariate statistical techniques such as principal component analysis (PCA) and general discriminant analysis (GDA). The use of 1H-(13)C HMBC coupled with appropriate statistical analysis seems to be an efficient technique for the classification of honeys.  相似文献   
69.
Colletotrichum gloeosporioides is the causal agent of Camellia oleifera anthracnose, mainly infecting fruits and leaves. The fungus secretes degrading enzymes to destroy the cuticle of aerial plant parts and help infect the host successfully. To validate whether a cutinase gene (CglCUT1) was required for cutinase activity and pathogenicity of C. gloeosporioides, the CglCUT1 gene was cloned and analyzed. The characterization of CglCUT1 predicted protein suggests that the cloned DNA encoded a cutinase in C. gloeosporioides affecting C. oleifera. The CglCUT1 showed a high homology to those from C. gloeosporioides causing papaya anthracnose and C. capsici causing pepper anthracnose, as well as those of other ascomycetes. The whole CglCUT1 gene was knocked-out and the knockout mutant (?CglCUT39) was subsequently complemented using Agrobacterium tumefaciens mediated transformation. The knockout transformants exhibited significant decreases in cutinase activity and virulence compared with the wild-type strain. The complemented transformants of the disrupted transformant ?CglCUT39 showed a significant increase in cutinase activity and virulence compared with the disrupted transformant ?CglCUT39. This study suggests that the CglCUT1 gene has a positive effect on fungal virulence of the hemibiotrophic C. gloeosporioides on C. oleifera.  相似文献   
70.

Background

Since 1999, field evidence of transplacental infection by porcine circovirus type 2 (PCV2) and reproductive failure has been reported in pigs. The objective of this study was to evaluate the clinical and pathological consequences of PCV2 infection in conventional PCV2-seropositive gilts by insemination with PCV2b-spiked semen.

Results

Six PCV2 seropositive gilts were inseminated with PCV2b-supplemented semen (infected) and three animals with semen and cell culture medium (controls). Only three out of the six infected animals were pregnant by ultrasonography on day 29 after insemination, while two out of the three controls were pregnant. One control gilt aborted on day 23 after insemination but not due to PVC2. Viraemia was demonstrated in four out of six infected and in one control gilt that became infected with PCV2a. Anti-PCV2 antibody titres showed dynamic variations in the infected group throughout the study. Among infected gilts, the animal with the lowest anti-PCV2 titre (1/100) at the beginning of the experiment and another that reached a similar low value during the experiment showed evident seroconversion over time and had also PCV2 positive foetuses. One placenta displayed mild focal necrosis of the chorionic epithelium positively stained by immunohistochemistry for PCV2 antigen.

Conclusions

PCV2-seropositive gilts can be infected with PCV2 after intrauterine exposure and low maternal antibody titre may increase the probability of a foetal infection.  相似文献   
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