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1.
New Forests - Adventitious rooting (AR) is an obligatory step for vegetative propagation of commercial woody species. Paper industries have interest in Eucalyptus globulus Labill and its hybrids...  相似文献   
2.
Actinobacillus pleuropneumoniae, the causative agent of porcine pleuropneumonia, produces Apx toxins that are recognized as major virulence factors. Recently, we showed that ApxIIIA-cytotoxic activity specifically targets Sus scrofa leukocytes. Since both LtxA from Aggregatibacter actinomycetemcomitans (aggressive periodontitis in humans) and LktA from Mannheimia haemolytica (pneumonia in ruminants) share this characteristic, respectively towards human and ruminant leukocytes, and because both use the CD18 subunit to interact with their respective LFA-1, we hypothesized that ApxIIIA was likely to bind porcine CD18 to exercise its deleterious effects on pig leukocytes. A β 2−integrin-deficient ApxIIIA-resistant human erythroleukemic cell line was transfected either with homologous or heterologous CD11a/CD18 heterodimers using a set of plasmids coding for human (ApxIIIA-resistant), bovine (-resistant) and porcine (-susceptible) CD11a and CD18 subunits. Cell preparations that switched from ApxIIIA-resistance to -susceptibility were then sought to identify the LFA-1 subunit involved. The results showed that the ApxIIIA-resistant recipient cell line was rendered susceptible only if the CD18 partner within the LFA-1 heterodimer was that of the pig. It is concluded that porcine CD18 is necessary to mediate A. pleuropneumoniae ApxIIIA toxin-induced leukolysis.  相似文献   
3.
Adventitious rooting is essential for vegetative propagation of woody species. We studied the effects of auxin and light on the development of adventitious roots in cuttings obtained from seedlings of Eucalyptus saligna Smith and E. globulus Labill in an attempt to characterize the adventitious rooting process and identify factors controlling rhizogenesis. Root development was scored as rooting percentage, root density (roots per rooted cutting), mean rooting time and root length. In both species, rooting time was reduced in the presence of auxin. Cuttings from 2-month-old E. saligna seedlings were responsive to lower auxin concentrations than comparable cuttings from E. globulus seedlings. Cuttings from 3-month-old E. saligna seedlings rooted promptly and rooting was not significantly affected by light conditions. In contrast, rooting of cuttings from 3-month-old E. globulus seedlings exhibited recalcitrant behavior and no roots were formed if illuminated during the root formation phase. Effective root regeneration of E. globulus cuttings was obtained by a 4-day exposure to 10 mg l(-1) IBA and culture in darkness during the root formation step. Loss of rooting capacity with seedling age was more pronounced in E. globulus than in E. saligna. The possibility of switching adventitious rooting off and on by manipulating light regime and exogenous auxin supply in E. globulus, and the constitutive nature of rooting in E. saligna may provide useful models for examining the rooting process at the biochemical and molecular levels in Eucalyptus.  相似文献   
4.
Cutin in tomato peels was depolymerized in methanolic base to yield cutin monomers or a mixture of cutin oligomers. These products were isolated by typical solvent extraction methods or by precipitation, and the isolates were characterized by chromatographic and spectroscopic analyses. It was determined that the compositions of the isolates from both isolation procedures were similar, although solvent extraction gave higher yields. However, the precipitation method, which is easy to carry out and avoids the use of undesirable organic solvents, may be preferable in commercial processes for recovering these compounds.  相似文献   
5.
Anthocyanin pigments in the berries of bagua?u (Eugenia umbelliflora Berg), a tropical fruit from Brazil, were extracted with 0.1% HCl in ethanol, and the crude anthocyanin extract was purified by Amberlite XAD-7 open-column chromatography. Six major anthocyanins were isolated by preparative HPLC, and their chemical structures were identified by spectroscopic methods (TLC, UV-vis, MS, and (1)H NMR). Delphinidin 3-O-beta-glucopyranoside, cyanidin 3-O-beta-glucopyranoside, petunidin 3-O-beta-glucopyranoside, pelargonidin 3-O-beta-glucopyranoside, peonidin 3-O-beta-glucopyranoside, and malvidin 3-O-beta-glucopyranoside were identified. On the basis of chromatographic data the total anthocyanin content was 342 mg/100 g of fresh bagua?u berries. Therefore, the concomitant presence of six anthocyanins in a single plant species makes this product promising as a new pigment source.  相似文献   
6.
The objective of this study was to compare the physico-chemical properties and antioxidant activity of six apple cultivars grown in southern Brazil. Apple peel color, dry matter, total soluble solids, pH, total sugars, titratable acidity, total phenolics, total monomeric anthocyanin and total antioxidant activity were measured in the apple cultivars Imperatriz, Daiane, Fred Hough, Fuji Suprema, Galaxy and Baronesa. The results showed great quantitative differences in the composition of the apple cultivars. Of all the cultivars, the peel of Galaxy was slightly more red-colored and that of Fred Hough was the least red-colored. The dry matter varied from 15.24% (Galaxy) to 19.55% (Fuji Suprema), the soluble solids content was between 11.8 (Fred Hough) and 14.0 (Daiane) °Brix, pH values varied from 3.90 (Imperatriz) to 4.27 (Fred Hough), the total sugar content (g 100 g−1) ranged from 11.54 (Imperatriz) to 14.78 (Fuji Suprema) and the titratable acidity content (g 100 g−1) varied from 0.20 (Baronesa) to 0.36 (Imperatriz). The total phenolic content (GAE 100 g−1 fresh matter) observed in the apple cultivars was between 105.4 (Baronesa) and 269.7 mg (Imperatriz). The values of the total anthocyanin content (mg 100 g−1 FM) ranged from 4.79 (Fred Hough) to 41.96 (Galaxy). The highest total antioxidant activity was observed in Imperatriz (739 μmol TEAC 100 g−1 FM), while the lowest value was found in Fuji Suprema (335 μmol TEAC 100 g−1 FM). There was a strong correlation between total monomeric anthocyanin content and all peel color measurements and between antioxidant activity and total phenolic content. The results suggested that genotype is the main factor that determines the composition of bioactive compounds in apples and this provides important information on how to make the best use of the apple cultivars investigated.  相似文献   
7.
The total phenolic, flavanol, monomeric anthocyanin contents and the antioxidant activity of flesh and peel of 11 apple cultivars from Brazil were investigated. Concentrations of the parameters measured differed significantly among the apple cultivars and were highest in the peel compared to the flesh. Total phenolic content (mg GAE/100 g fresh matter) ranged from 128.3 (Golden Delicious) to 212.0 (Epagri-F5P283) in the flesh and 304.6 (Golden Delicious) to 712.6 (Catarina) in the peel. Total flavanol content (mg CAE/100 g fm) varied from 11.7 (Epagri-SJ11) to 28.2 (Epagri-F43P23) and from 32.4 (Epagri-SJ11) to 147.7 (Catarina) in the flesh and peel, respectively. COOP-24 peel had the highest total anthocyanin content. The Epagri-F5P283 and Epagri-F43P23 flesh and Catarina peel had the highest antioxidant activity while Golden Delicious flesh and peel had the lowest. The total phenolic content and antioxidant activity were significantly correlated in both flesh (R2 = 0.717) and peel (R2 = 0.716). The contribution of phenolics to the antioxidant activity in peel suggests that their removal may induce a significant loss of antioxidants.  相似文献   
8.
Nitrite and nitrate are formed by endogenous synthesis in the human intestine   总被引：23，自引：0，他引：23  
Studies of nitrate balance in humans and analyses of fecal and ileostomy samples indicate that nitrite and nitrate are formed de novo in the intestine, possibly by heterotrophic nitrification. These findings significantly alter our previous conceptions of human exposure to nitrite and suggest an even wider role for nitrite in the etiology of human cancer.  相似文献   
9.
On‐board Brazilian sardinella (Sardinella brasiliensis) conservation system based on cooling in ice, but in recent years, fishing boats have been applying immersion in chilled brine as a storage system on‐board. This study evaluated this system concerning physicochemical quality (total volatile bases, pH, histamine, moisture) of the fish and cation concentrations. Offshore (on‐board) data were collected (total storage time, over time temperature, fish mass captured by bid, load capacity in use and available) to assess the efficiency and viability. The results showed that this system is useful in maintaining the physicochemical quality of the fish since the samples met the quality standards required by law. Data showed high levels of sodium in fish muscle, which are strongly influenced by the immersion time, suggesting the need for standardization of the method considering the risks associated with consumption of foods with high levels of sodium.  相似文献   
10.
Plant Foods for Human Nutrition - Yellow guava (Psidium cattleianum Sabine) has received considerable attention in the last years because of their high content in bioactive compounds with potential...  相似文献   
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