Addition of NaCl or sucrose to egg albumen prior to high-pressure treatment (up to 10 min at 800 MPa) prevented insolubilization or gel formation after pressure treatment. As a consequence of protein unfolding, the treated albumen had increased viscosity but retained its foaming and heat-gelling properties. Susceptibility of egg albumen proteins to hydrolysis by trypsin increased dramatically after pressure treatment. The S-form of ovalbumin, the presence of which is an index of egg aging, was not found in any of the pressure-treated samples, which also did not display evidence for covalent protein aggregation. However, recognition of ovalbumin by an anti-ovalbumin antiserum was reduced to 40% of that of untreated sample. 相似文献
Maize is used as an alternative to wheat to elaborate foodstuffs for celiac patients in a gluten-free diet. However, some
maize prolamins (zeins) contain amino acid sequences that resemble the wheat gluten immunodominant peptides and their integrity
after gastrointestinal proteolysis is unknown. In this study, the celiac IgA-immunoreactivity to zeins from raw or nixtamalized
grains, before and after peptic/tryptic digestion was evaluated and their possible immunogenicity was investigated by in silico methods. IgA from some celiac patients with HLA-DQ2 or DQ8 haplotypes recognized two alpha-zeins even after peptic/tryptic
proteolysis. However, digestion affected zeins after denaturation, reduction, and alkylation, used for identification of prolamins
as alpha-zein A20 and A30 by MS/MS sequencing. An in silico analysis indicated that other zeins contain similar sequences, or sequences that may bind even better to the HLA-DQ2/DQ8
molecules compared to the already identified ones. Results concur to indicate that relative abundance of these zeins, along
with factors affecting their resistance to proteolysis, may be of paramount clinical relevance, and the use of maize in the
formulation and preparation of gluten-free foods must be reevaluated in some cases of celiac disease. 相似文献
Plant Foods for Human Nutrition - This study aims at understanding the relation among sprouting time (from 12 up to 72 h), changes in protein and starch components, and flour functionality... 相似文献
The evaluation of the ecotoxicity effects of some heavy metals on the plant growth and metal accumulation in Ocimum basilicum L. cultivated on unpolluted and polluted soils represented the objective of the present study.
Materials and methods
The basil aromatic herb was evaluated in a laboratory experiment using soil contaminated with Cd, Co, Cr, Cu, Ni, Pb, and Zn, similar to the one from a mining area. The soils and different organs of the basil plants were analyzed, the total contents of the added elements being determined using inductively coupled plasma optical emission spectrometry. The ability of basil plants to accumulate metals from soil and to translocate them in their organs was evaluated by transfer coefficient, translocation factor, enrichment factor, and geo-accumulation index determinations.
Results and discussion
The basil plants grown in the metal-polluted soil showed stimulation effects comparing with the plants from the control soil. At the end of the exposure period, the plants had a visible increase of biomass and presented inflorescences and the leaves’ green pigment was intensified. The metals gathered differently in plant organs: Cd, Co, Cr, and Pb were accumulated in roots, while Cu, Ni, and Zn in flowers. Cr and Pb exceeded the toxic levels in roots. Also, the heavy metal intake depends on the plant development stages; thus, Cd, Cr, and Pb were accumulated more in mature plant leaves. The Cd and Pb contents were higher than the World Health Organization and European Commission permissible limits.
Conclusions
The experimental results revealed that the basil plants exposed to a mixture of heavy metals have the potential to reduce the metal mobility from soil to plants. Translocation process from roots to flowers and to leaves was observed for Cu, Ni, and Zn, emphasizing a competition between metals. The calculated bioaccumulation factors were insignificant, but Cd and Pb concentrations exceeded the legal limits in the mature plants, being restricted for human or animal consumption.
The growth of evergreen azaleas (Rhododendron spp.) can be altered by iron (Fe) chlorosis when plants are cultivated in a neutral-alkaline substrate. In this study, morphological and physiological responses to alkalinity and Fe deficiency were evaluated in five diploid Japanese azaleas to assess their potential as resources for breeding. R. obtusum ‘Kirin’, R. indicum ‘Shinsen’, R. × pulchrum ‘Sen-e-oomurasaki’, R. indicum ‘Osakazuki’, and R. ripense were pot cultivated in a peat-based substrate for 10 weeks, in acid and alkaline growing media with both adequate and inadequate Fe nutrition. Plant performance was generally affected by high pH of the substrate, while Fe deficiency by itself influenced few of the evaluated parameters, possibly due to the complex adaptive response mechanisms of these slow growing ornamental shrubs. According to the biochemical and physiological variations recorded on a long period of cultivation, R. indicum ‘Osakazuki’ reported the best performance. This azalea could be a valuable resource for breeders. 相似文献
Wild blueberries are a rich source of polyphenols and other compounds that are highly metabolized by the intestinal microbiota and may, at the same time, affect the intestinal environment itself. A repeated-measure, crossover dietary intervention on human volunteers was designed to study the effect of six week consumption of a wild blueberry ( Vaccinium angustifolium ) drink, versus a placebo drink, in modulating the intestinal microbiota. Relative to total eubacteria, Bifidobacterium spp. significantly increased following blueberry treatment (P ≤ 0.05), while Lactobacillus acidophilus increased after both treatments (P ≤ 0.05). No significant differences were observed for Bacteroides spp., Prevotella spp., Enterococcus spp., and Clostridium coccoides . Bifidobacteria, which have been largely proposed to be of benefit for the host, appeared to be selectively favored suggesting an important role for the polyphenols and fiber present in wild blueberries. Results obtained suggest that regular consumption of a wild blueberry drink can positively modulate the composition of the intestinal microbiota. 相似文献
