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991.
Grethel Teresa Choque Delgado Wirla Maria da Silva Cunha Tamashiro Mário Roberto Maróstica Junior Glaucia Maria Pastore 《Plant foods for human nutrition (Dordrecht, Netherlands)》2013,68(3):222-228
Yacon (Smallanthus sonchifolius) is an Andean tuberous root that is regarded as a functional food given that it contains fructooligosaccharides (FOS), inulin and phenolic compounds. The consumption of FOS and inulin improves the growth of bifidobacteria in the colon, enhances mineral absorption and gastrointestinal metabolism and plays a role in the regulation of serum cholesterol. Furthermore, the literature reports that the consumption of these prebiotics promotes a positive modulation of the immune system, improving resistance to infections and allergic reactions. Certain studies have demonstrated the potential of yacon as an alternative food source for those patients with conditions that require dietary changes. This review intends to describe the potential of yacon as a prebiotic and its cultivation and industrial processing for human consumption. 相似文献
992.
The authors demonstrate a novel, efficient, and widely applicable approach to direct the patterning of ligand-functionalized organic nanoparticles derived from albumin on nonconductive, biodegradable polymeric substrates. In contrast to traditional deposition methods for inorganic nanoparticles, the approach involves oxygen plasma treatment of spatially restricted regions on a nonbiopermissive polymer. Albumin nanoparticles conjugated with a truncated fragment of fibronectin containing the Arg-Gly-Asp domain were successfully patterned and used as templates to elicit adhesion and spreading of human mesenchymal stem cells and fibroblasts. Attachment and spreading of both cell types into the plasma-exposed polymer areas was considerably more pronounced than with the ligand alone. The authors hypothesize that the underlying mechanism is oxygen plasma treatment-induced selective enhancement of ligand exposure from the deposited functionalized nanoparticles, which facilitates ligand receptor clustering at the cell membrane. The results highlight a promising nanoscale approach to modulate ligand presentation and spatially direct cell attachment and phenotypic behaviors. 相似文献
993.
María Renée Pappa Patricia Palacios de Palomo Ricardo Bressani 《Plant foods for human nutrition (Dordrecht, Netherlands)》2010,65(2):130-135
The objective of the study was to obtain information on the chemical composition, functional properties, sensory quality and
protein value of tortillas made from the nixtamalization of maize using either lime or wood ashes. The Ca, K, Mg, Fe, and
Zn content of lime and wood ashes showed lime to be high in Ca content while wood ash contained more K and about 71% of the
Ca content of lime. Both contained relatively high levels of Mg, Fe and Zn, but more so in the wood ashes. The level of reagent
for nixtamalization was set at 0.8% of the maize weight. All other processing conditions were kept constant. The pH of the
cooking solution was 12.0 for lime and 10.9 for wood ash. The moisture content of maize at 60 min of cooking was 45.8% for
both treatments, however after 12 h of soaking, moisture level was 51.0% for the lime treatment and only 46.8% for the ash
treatment. Solids (2.4%) in the lime cooking liquor were higher than in the wood ash liquor (1.0%). Chemical composition changes
were similar between treatments in masa and tortilla; however, both masa and tortillas absorbed relatively high levels of
all minerals including Fe and Zn from the wood ash treatment. The different treatment influenced functional properties particularly
hardness and color. Tortilla characteristics were also similar. Protein quality of both alkali cooked products was lower than
that of raw corn, more so the product from the wood ash treatment. Although some differences were observed in the sensory
studies, human subjects did not dislike the wood ash made tortillas. 相似文献
994.
Agronomic and fruit quality traits were evaluated and compared for three consecutive years on 1,111 seedlings coming from
15 peach and nectarine breeding crosses, grown under a Mediterranean climate. Significant differences among and within the
different progenies were found for most of the traits analyzed. The breeding population segregated for several Mendelian characters
such as peach or nectarine fruit, round or flat fruit, yellow or white flesh and freestone or clingstone. In addition, aborting
fruit and flat fruit trees were found in our progeny, and our data seem to support multi-allelic control of both flat shape
and aborting fruit. The variation within the progenies of some traits such as blooming and harvesting date, yield, fruit weight
and SSC was continuous, suggesting a polygenic inheritance. Relationships between qualitative pomological traits and these
agronomic and fruit quality parameters were also found. Valuable correlations among agronomic and fruit quality parameters
were found, although coefficients of variation depending on the progeny should be considered. In addition, principal component
analysis (PCA) revealed several relationships among quality traits in the evaluated progenies. Based on this evaluation, 26
outstanding genotypes were pre-selected from the initial breeding population for further studies. 相似文献
995.
996.
Julieta R. Mendieta Carmela Fimognari Gustavo R. Daleo Patrizia Hrelia María G. Guevara 《Fitoterapia》2010,81(5):329-335
StAPs are potato aspartic proteases with cytotoxic activity against plant pathogens and spermatozoa. StAPs cytotoxic activity is selective, since these proteins do not exert toxic effect on plant cells and erythrocytes. In this work, we investigated the capacity of StAPs to exert cytotoxicity on human leukaemia cells. Obtained results show that StAPs induce apoptosis on Jurkat T cells after a short time of incubation in a dose-dependent manner. However, no significative effect on the T lymphocytes viability was observed at all StAPs incubation times and concentrations tested. These results suggest that StAPs can be conceptually promising leads for cancer therapy. 相似文献
997.
Rüdiger Otto Bertil O. Krüsi Juan D. Delgado José María Fernández-Palacios Eduardo García-Del-Rey José Ramón Arévalo 《Annals of Forest Science》2010,67(7):709-709
| – |
• Canarian Juniper woodlands, now very scarce, are rich in endemic and endangered plants. However, many aspects of juniper
regeneration are almost unknown. 相似文献
998.
Rüdiger Otto Eduardo García-del-Rey Pascual Gil Muñoz José María Fernández-Palacios 《European Journal of Forest Research》2010,129(4):499-508
The Canarian pine (Pinus canariensis) exhibits a striking combination of high adult resistance to fire and intermediate serotiny. Hence, the study of its post-fire
regeneration can support valuable new insights about functional adaptations to fire. Here, we analyse the first-year seedling
establishment after fire in a P. canariensis forest on the northern slope of Tenerife, Canary Islands. The effects of fire severity and other explanatory variables on
the seedling density recorded 9 months after fire were examined. We detected a clear unimodal relationship between seedling
density and fire severity, with maximum regeneration associated with intermediate fire severity and no regeneration associated
with very high crown damage. The results suggested that high severity fires may have caused the partial destruction of the
aerial seed bank and/or the creation of unfavourable seedbed conditions for germination and seedling emergence. The density
of large pine trees, reflecting seed availability, was the second most important factor explaining the distribution of seedlings.
Cover of scorched needle litter on the ground correlated strongly and positively with pine seedling density and negatively
with fire severity. The complete lack of regeneration at sites most strongly affected by fire does not represent a major threat
for the stand recovery of the Canarian pine, due to the very high tree resistance to fire and the tremendous capacity of the
Canarian pine to resprout after fire. The observed very high seedling densities at sites with intermediate fire impacts can
probably be related to both the complete liberation of the seed bank (including seeds stored in serotinous cones) and favourable
micro-environmental conditions for seed germination and seedling establishment. 相似文献
999.
Julian Perez Sanford Eigenbrode Luko Hilje Robert Tripepi María Elena Aguilar Francisco Mesén 《Journal of pest science》2010,83(2):95-104
In order to determine their effects on growth and mortality of instar II Hypsipyla grandella (Zeller), larvae were fed with leaf disks taken from shoots of susceptible species (Cedrela odorata L. and Swietenia
macrophylla King) scions grafted onto resistant ones (Khaya senegalensis Desr. A. Juss and Toona ciliata M. Roem.), from their reciprocal grafts, and from both intact and autografted plants. In addition, crude leaf extracts from
the susceptible and resistant plants, as well as from C. odorata grafted onto T. ciliata plants, were tested on C. odorata leaf disks. Mortality was evaluated 2, 10, and 25 days after starting the bioassay. Leaf area consumed and weight gain per
larva were assessed 2 days after starting bioassay. Time to reach pupation, pupal weight and length 1 day after pupation,
and time to adult stage and appearance of wings were determined at the end of the bioassay. Plant species significantly affected
mortality (P ≤ 0.04) throughout the test. Eighty to 100% of larvae fed leaf disks from intact T. ciliata and its autograft, or C. odorata onto T. ciliata and its reciprocal graft died in the first 2 days of evaluation. All other factors measured, except pupal weight and length,
were also affected (P ≤ 0.01) by the leaf disks. Intact resistant plants and reciprocal grafted plants reduced leaf consumption and caused larval
weight loss. Larvae fed on K. senegalensis grafted onto S. macrophylla extended by 8 days the time to pupa and to adult stages and induced abnormal wing formation compared to larvae fed intact
leaves of C. odorata. Crude extracts from resistant plants equally affected larval survival and performance compared to crude extract from C. odorata grafted onto T. ciliata plants, and these extracts were more detrimental to larvae than those from susceptible species. This study demonstrated that
grafting borer-susceptible species on resistant rootstocks can affect the survival and performance of instar II H. grandella larvae. 相似文献
1000.
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