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51.
The presence of antioxidant compounds can be considered as a quality parameter for edible fruit. In this paper, we studied the antioxidant compounds in raspberry (Rubus idaeus) fruits by high-performance liquid chromatography (HPLC) coupled to an on-line postcolumn antioxidant detection system. Both developmental and genetic factors were assessed by comparing fruits from a single cultivar of different ripening stages and by comparing ripe fruits of 14 raspberry cultivars, respectively. The HPLC-separated antioxidant compounds were identified using HPLC-photodiode array coupled to mass spectrometry (quadrupole time-of-flight tandem mass spectrometry), using a reference lock mass for determining accurate masses. The dominant antioxidants could be classified as anthocyanins, ellagitannins, and proanthocyanidin-like tannins. During fruit ripening, some anthocyanins were newly produced, while others, like cyanidin-3-glucoside, were already present early in fruit development. The level of tannins, both ellagitannins and proanthocyanidin-like tannins, was reduced strongly during fruit ripening. Among the 14 cultivars, major differences (>20-fold) were observed in the levels of pelagonidin type anthocyanins and some proanthocyanidin type tannins. The content of ellagitannins varied approximately 3-fold. The findings presented here suggest that the content of individual health-promoting compounds varies significantly in raspberry, due to both developmental and genetic factors. This information will assist in the future development and identification of raspberry lines with enhanced health-promoting properties.  相似文献   
52.
The Baobab tree (Adansonia digitata L.) is a key multipurpose species for the African region. In the recent years there has been an extended commercial interest for different A. digitata products. As a spectacular African key species there has been a growing interest from NGO′s and various research groups. A research group, focussing on the following countries Burkina Faso, Mali and Niger, has participated in a concerted research action with cross counter disciplinary cooperation between plant physiology, population genetics, tree breeding, food science, and socioeconomics. This paper presents a review and the way knowledge gaps are being addressed using the above mentioned approach. The overall work was initiated in 2005–2006 when a large collection of A. digitata seeds was carried out in 15 African countries. Fourteen populations were selected in Burkina Faso, Mali, and Niger including more than 400 superior trees, and many of the trees have been selected along with farmers in a participatory process. Studies have been initiated in all countries on geographic variation of growth, adaptive and phenological traits. This includes studies in the nursery, establishment of international provenance series, seed orchards and studies of gene flow and phylogeographic variation with various markers. Specific nursery trials have been established in order to study provenance and progeny performance related to drought stress. Several stress related characteristics are being measured. Preliminary observations showed large morphological variation between African provenances of A. digitata. Food properties of plant parts have been studied within and between populations. This includes studies of total biomass production, vitamin A, B1, B2, and various minerals. The influence of stress will be related to these parameters. Fruits, which are rich in sugar and vitamin C, are used as an ingredient in juice and other foods. Seeds can be used directly as food ingredient or in fermented condition (Maari). The fermentation process was previously poorly described. Therefore, the microorganisms associated with Baobab seeds fermentation have been identified and a starter cultures for control production has been proposed. The efficiency of dissemination of superior A. digitata trees depends on vegetative propagation. Various grafting methods are currently being tested in cooperation with farmers. Micropropagation is tested as well as a method for clone propagation. The accumulated knowledge will be applied for a domestication strategy of A. digitata in Burkina Faso, Mali and Niger. The outcome from this study will be guidelines for protection and management of the germplasm of A. digitata resources.  相似文献   
53.
54.
In this study, anesthesia levels obtained with tiletamine-zolazepam (TZ) and ketamine-midazolam (KM) with or without xylazine (X) were compared in rabbits. Reflexes (corneal, palpebral and withdrawal), blood parameters (PaO2, PaCO2, pH and ions HCO3-), cardiovascular function (heart rate and mean arterial blood pressure) and body temperature were evaluated before and after the injections of the anesthetic combination in the same rabbits (n = 10). With KM and TZ, no suppression of reflexes occurred. The body temperature and pH decreased and HCO3- increased similarly to KMX et TZX. Some physiological and blood parameters were less (PAM, PaCO2) and not (PaO2) affected comparatively to KMX et TZX. These protocols were of short duration of action and did not offer any anesthesia or analgesia. Therefore, their utilization should be restricted to short procedures where no painful manipulations are performed. Ketamine-midazolam-xylazine and tiletamine-zolazepam-xylazine on the other hand are indicated for interventions that require anesthesia. With these combinations, all reflexes were absent for 30-45 and 60-90 min following injections of KMX et TZX, respectively. However, these combinations induce cardiac depression, as well as a decrease of all measured blood parameters and body temperature and a reduction of PaO2. Supplementation with oxygen is recommended with the introduction of xylazine in the protocol.  相似文献   
55.
Equine influenza virus is a leading cause of respiratory disease in the horse population; however, the susceptibility of old horses to EIV infection remains unknown. While advanced age in horses (>20 years) is associated with age-related changes in immune function, there are no specific recommendations regarding the vaccination of older horses even though a well-characterized effect of aging is a reduced antibody response to standard vaccination. Therefore, we evaluated the immunological and physiological response of aged horses to a live non-replicating canarypox-vectored EIV vaccine and subsequent challenge infection. Vaccination of the aged horses induced EIV-specific IgGb and HI antibodies. No specific increase in cell-mediated immune (CMI) response was induced by the vaccine as determined by EIV-specific lymphoproliferation and the detection of EIV-specific IFNγ+ CD5+T cells, IFNγ, IL-2, IL-4 and IL-13 mRNA expression. Non-vaccinated aged horses exhibited clinical signs of the disease (coughing, nasal discharge, dyspnea, depression, anorexia) as well as increased rectal temperature and viral shedding following challenge. Concomitant with the febrile episodes, we also observed increased production of pro-inflammatory cytokine mRNA production in vivo using RT-PCR. Naïve horses were included in this study for vaccine and challenge controls only. As expected, the canarypox-vectored EIV vaccine stimulated significant CMI and humoral immune responses and provided significant protection against clinical signs of disease and reduced virus shedding in naive horses. Here, we show that aged horses remain susceptible to infection with equine influenza virus despite the presence of circulating antibodies and CMI responses to EIV and vaccination with a canarypox-vectored EIV vaccine provides protection from clinical disease.  相似文献   
56.
Nutrients diffusing from swine manure through hollow-fibre dialysis improve the dry matter yield of the marine diatom Phaeodactylum tricornutum grown under natural light by 40% (72·6 versus 51·6 mg liter−1 day−1) compared to natural estuarine water. The increase is achieved despite incomplete nutrient removal and is ascribed to the higher concentrations of ammonia and orthophosphate supplied by swine manure dialysate. Growth promoting factors aside, the exclusion of predators and particles causing turbidity as well as the limited dialysis of heavy metals eliminate or greatly attenuate the growth retarding effects of such undersirable constituents of swine manure.  相似文献   
57.
Summary

Globe artichoke (Cynara cardunculus L. var. scolymus) provides a rich dietary source of bio-active compounds derived from phenylpropanoid metabolism, notably caffeoylquinic acids (CQAs) and flavonoids. Micropropagation techniques have been established for this species, but in vitro cultures have not yet been extended to generate an efficient system for the induction of callus tissue. In this study, we compared more than 100 combinations of media supplements (e.g., phytohormones, absorbers of polyphenols, and inhibitors of polyphenol oxidase), along with various light regimes, and three different genotypes of globe artichoke to define the optimal conditions for callus induction from leaf explants. This led to the elaboration of an in vitro culture protocol which resulted in a high frequency of callus induction after just 1 week in culture. The procedure used leaf explants from virus-free, meristem culturederived plantlets. Quantitative HPLC analysis revealed that, as in globe artichoke leaves, the predominant phenolic esters present in callus were mono- and di-caffeoylquinic acids (diCQA). The concentration of diCQA was three- to five-fold higher in calli than in leaves. The exposure of calli to UV-C light further enhanced the levels of CQAs. In vitro callus culture combined with UV-C irradiation may thus represent a viable production system for diCQA that is suitable for the synthesis of pharmacologically-active compounds.  相似文献   
58.
为了满足营养需求和后代对环境的要求,对农业实践的深刻反思势在必行。像可持续发展和能源效率标准将会在动物饲料领域发挥越来越重要的作用。  相似文献   
59.
In tomato, the predominant flavonoid is quercetin-3-rutinoside (rutin). In this study, we aim to investigate the phenylalanine ammonia-lyase (PAL) and the quercetin-3-O-glucosyl transferase (3-GT) reactions in the formation of rutin during tomato fruit ripening. Tomatoes of the Moneymaker variety at different development stages (green, breaker, turning, pink, red, and deep red) were divided into flesh and peel fractions. In each sample, both the content of rutin and the enzymatic activities for PAL and 3-GT were recorded. The highest activities of PAL were recorded in the peel of turning fruit (3,000 μkat/mg fresh weight). In fruit flesh, maximal activity was observed in red fruit (917.3 μkat/mg). For both tissues, PAL activity strongly decreased at the final (deep red) fruit stage. The activity of 3-GT in peel peaked in the turning fruit stage (50.7 pkat/mg), while in flesh maximal activity (33.4 pkat/mg) was observed in green fruit, which rapidly declined at the turning stage. Higher levels of rutin were detected in the tomato peel compared to the flesh part with the highest level being found at the green stage. The relation of PAL and 3-GT activities to rutin content is also evaluated.  相似文献   
60.
In Western Africa, interactions between trees and agricultural crops are a key element in determining parkland management in an agricultural environment that is rapidly changing. Eggplant (Solanum melongena), chilli pepper (Capsicum annuum), taro (Colocasia esculenta) and pearl millet (Pennisetum glaucum) were tested for their shade tolerance under Parkia biglobosa trees in south-central Burkina Faso using a split-plot design. Soil characteristics, chlorophyll fluorescence and crop growth and yield were measured to quantify the effect of P. biglobosa on the crops and their environment. The experiment ran during 2?years. P. biglobosa suppressed the vegetative growth and yield of pearl millet in both years. Eggplant and chilli pepper were severely injured by the rains and produced fruits only during the first year. Eggplant yields were suppressed by trees to between one third and one tenth of the yield in the control plots. However, chilli pepper yields increased by up to 150% when grown under the tree canopy compared to the control. In both years, the vegetative growth and yield of taro was higher when grown in the shade than outside the tree canopy.  相似文献   
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