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1.
The essential elements copper (Cu), iron (Fe), zinc (Zn) and manganese (Mn) were analyzed in fresh asparagus to determine the effects of the vegetative cycle of the plant on the micronutrient content. Asparagus samples were classified in two groups by diameter (<11 mm and >14 mm). Asparagus from a sample group with the same diameter were divided into two portions (apical and basal) according to distance from the tip. The concentrations of copper, iron, zinc and maganese increased during the vegetative cycle of the asparagus, mainly in the apical portion which showed significantly greater concentrations with respect to the basal portion. The >14 mm diameter asparagus presented higher levels of copper, zinc and manganese, whereas the concentration of iron was greater in the <11 mm diameter asparagus. The mean element levels were (mg/kg dry weight): Cu, 18.9±3.9; Fe, 91.7±33.7; Zn, 69.5±24.6 and Mn, 20.9±5.0).  相似文献   

2.
对46份芦笋种质资源各器官中氮、磷、钾、钙、镁含量及其相关性进行分析。结果表明:芦笋各器官中氮、磷元素平均含量为嫩茎根叶母茎;钾元素平均含量为嫩茎母茎叶根;钙元素平均含量为嫩茎根母茎叶;镁元素平均含量由为根≈嫩茎母茎叶。芦笋的嫩茎中5种元素的平均含量均较高,嫩茎中氮的含量范围是40.68~87.85 g/kg,磷的含量范围是2.33~15.24 g/kg,钾的含量范围是36.15~76.97 g/kg,钙的含量范围是4.45~27.61 g/kg,镁的含量范围是1.08~6.08 g/kg。其中对人体有益的钙、镁元素含量变异程度较大,钙元素含量最高的品种为‘Purple Passion’,镁元素含量大于5 g/kg的品种有2个,分别是‘UC157’、‘JK107’。由此可见,芦笋中的氮、磷、钾、钙、镁元素含量具有明显的器官差异性和品种差异性。  相似文献   

3.
Six genotypes of potato were compared with two commercial cultivars, Kufri Chandramukhi and Kufri, Chamatkar for their yield and mineral contents (i.e., iron, copper, zinc, sodium, calcium, magnesium and phosphorus). There were significant differences amongst different genotypes with respect to yield and mineral contents. The cultivar Kufri Chandramukhi, which gave also significantly highest tuber yield during both years, was found to be richest in copper, zinc and potassium. The genotypes EM/B-1601 and JF-4835 were found to be highest in iron content. The highest quantities of sodium, potassium, and magnesium were detected in the cultivar Kufri Chamatkar. The genotype J.F. 5106 was also found to be rich in magnesium content which was comparable to Kufri Chamatkar. The highest quantities of phosphorus and calcium were found in genotypes J.F. 4835 and EM/B-859 respectively. The genotype J.F. 547 was found to be poorest in iron, copper, zinc, sodium and potassium.  相似文献   

4.
Ascorbic acid content in green and ripe fruits and zinc, copper, manganese, iron, sodium, potassium, calcium, magnesium and phosphorus content in dry fruits were found to vary significantly in different varieties of chilli (Capsicum annuum L.). Ascorbic acid content in ripe fruits of all of the eleven chilli varieties was higher than in the corresponding green fruits. Path coefficient analysis showed that number of days to fruit ripening, fruit surface area, fruit length, dry and fresh fruit yield, ascorbic acid content in green fruits and iron, calcium, magnesium and copper content in dry fruits influenced ascorbic acid content in ripe fruits of chilli.  相似文献   

5.
The aim of the present study was to evaluate some chemical and mineral characteristics and functional and rheological properties of Canna and Arrowroot starches produced in the Venezuelan Andes. Canna starch showed a higher (P < 0.05) moisture, ash, and crude protein content than arrowroot starch, while crude fiber, crude fat, and amylose content of this starch were higher (P < 0.05). Starches of both rhizomes own phosphorus, sodium, potassium, magnesium, iron, calcium, and zinc in their composition. Phosphorus, sodium, and potassium are the higher in both starches. Water absorption, swelling power, and solubility values revealed weak bonding forces in Canna starch granules; this explained the lower gelatinization temperature and the substantial viscosity development of Canna starch during heating. Arrowroot starch showed a higher gelatinization temperature measure by DSC, than Canna starch and exhibited a lower value of ΔH. Both starches show negative syneresis. The apparent viscosity of Canna starch was higher (P < 0.05) than the Arrowroot starch values. The size (wide and large) of Canna starch granules was higher than arrowroot starch. From the previous results, it can be concluded that Canna and Arrowroot starches could become interesting alternatives for food developers, depending on their characteristics and functional properties.  相似文献   

6.
The goal of this study was to evaluate the effect of the physical modification by microwave irradiation on the mineral fraction and rheological properties of starch isolated from Canna edulis rhizomes. Phosphorus, sodium, potassium, magnesium, iron, calcium and zinc were evaluated using atomic absorption spectrophotometry. Rheological properties were determined using both the Brabender amylograph and Brookfield viscosimeter. Except for the calcium concentration, mineral contents decreased significantly (p < 0.05) after microwave treatment. The amylographic profile was also modified, showing increased pasting temperature range and breakdown index, whereas the viscosity peak, viscosity at holding (95°C) and cooling periods (50°C), setback and consistency decreased as compared to the native starch counterpart. Although viscosity decreased in the microwaved sample, presumably due to starch changes at molecular level, it retained the general pseudo plastic behavior of native starch. It is concluded that canna starch may be modified by microwave irradiation in order to change its functional properties. This information should be considered when using microwave irradiation for food processing. Furthermore, the altered functional attributes of canna modified starch could be advantageous in new product development.  相似文献   

7.
The objective of the study was to determine the rate and extent to which calcium (Ca), copper (Cu), magnesium (Mg), potassium (K), phosphorus (P), sodium (Na) and zinc (Zn) were released from polyester bags containing grass silages incubated in the rumens of cattle. The rate of mineral disappearance from the bags was faster than the rate of dry matter disappearance. The disappearance of each mineral element from the bags was characterized by a rapid release of the mineral within 2 h of placing the bags in the rumen followed by a slower release extending up to 48 h of rumen incubation. The extent to which each mineral was rapidly released from the silages differed significantly and the minerals were ranked in the order P < Zn < Ca < Cu < K < Mg < Na. There were no differences between minerals in the rate at which they were released during the slower phase.
Combination of these results with different rates of outflow of material from the rumen showed that for each of the minerals examined more than 0.65, on a proportional basis, was released from the silages; for Na the values were greater than 0.90. Indeed, all the residual Na and P remaining in the bags after 48 h rumen incubation could have resulted from bacterial  相似文献   

8.
Herbage samples are often taken for analysis in advisory problems concerning suspected mineral deficiencies in livestock. The adequacy of single samples is here assessed on two dissimilar sites. For this purpose S23 ryegrass was cut at similar stages of growth throughout the growing season and analyses carried out to determine the variation in the levels of calcium, phosphorus, potassium, sodium, magnesium, copper, cobalt and manganese resulting from different cutting dates. In many cases significant differences occurred between the levels of a particular element at different times during the year. These differences were large enough in some cases to influence advice based on a single result if taken in isolation.  相似文献   

9.
Trace elements in two varieties of spinach cultivated in soil with different levels of added iron were determined. Addition of iron to soil decreased potassium, sodium and magnesium contents in spinach markedly (p<0.05), while the contents of zinc, manganese and copper in spinach were not significantly altered (p>0.05). Differential behaviour of spinach varieties was found in the zinc, manganese and sodium contents.  相似文献   

10.
Content of selected minerals in spinach (Spinacea oleracea) andambat chuka (Rumex vesicarius) cultivated in soil fortified withdifferent chemical fertilizers was determined in a pot experiment.Addition of NPK (Nitrogen, Phosphorus and Potassium) fertilizer alongwith micronutrients, iron and zinc, enhanced the concentration of zinc,iron and magnesium in selected green leafy vegetables markedly (p<0.05),while the concentration of copper was not altered significantly(p>>0.05). Potassium content in the green leafy vegetables was notaffected (p>0.05) by the addition of chemical fertilizers to soil.Spinach and ambat chuka differed remarkably in their mineral contents.Contents of potassium, zinc and copper were significantly high in spinach,while the contents of magnesium and iron were markedly high in ambatchuka (p<0.05).  相似文献   

11.
The influence of a 3-week vegetarian diet and fasting on serum concentration of peroxides, lipids, apolipoproteins, and plasma fibrinogen was studied in ten middle-aged fibromyalgia/fibrositis patients (eight women, two men). Mean serum peroxide concentration (estimated as thiobarbituric acid reacting substances) was reduced from 3.60±0.14 to 2.82±0.15 umol/l (p=0.01) and plasma fibrinogen from 3.33±0.25 to 2.74±0.15 g/l (p=0.02). Serum total cholesterol fell from 6.61±0.50 to 4.83±0.35 mmol/l (p<0.0001), apolipoprotein B from 1.77±0.14 to 1.31±0.11 g/l (p<0.0001), and apolipoprotein A from 1.41±0.09 to 1.23±0.05 g/l (p=0.03). High density lipoprotein cholesterol concentration also decreased somewhat (from 1.26±0.09 to 1.07±0.04 mmol/l,p=0.03) An atherogenic index, reflecting the balance between low and high density lipoproteins, was reduced by 31% (from 5.74±0.79 to 3.97±0.60,p=0.02). The results suggest that vegetarian diet/fasting may have a beneficial influence on the concentration of serum peroxides and plasma fibrinogen concentration, and on the serum level of several lipoprotein-related coronary risk factors.  相似文献   

12.
The aim of this investigation was to find a proper harvesting period and establishing fern number, which effects the spear yield, bioactive compounds and antioxidant activities of Asparagus officinalis L. Spears were harvested at 2, 4, and 6 weeks after sprouting. Control for comparison was used without harvest. Spears and total yield increased with prolonged spear harvest period. In harvest of 6 weeks long optimum spear yield was the highest and fern numbers were 5?~?8. Bioactive compounds (polyphenols, flavonoids, flavanols, tannins and ascorbic acid) and the levels of antioxidant activities by ferric-reducing/antioxidant power (FRAP) and cupric reducing antioxidant capacity (CUPRAC) assays in asparagus ethanol extracts significantly differed in the investigated samples and were the highest at 6 weeks harvest period (P?<?0.05). The first and the second segments from the tip significantly increased with the increase of catalase (CAT). It was interesting to investigate in vitro how human serum albumin (HSA) interacts with polyphenols extracted from investigated vegetables. Therefore the functional properties of asparagus were studied by the interaction of polyphenol ethanol extracts with HSA, using 3D- FL. In conclusion, antioxidant status (bioactive compounds, binding and antioxidant activities) improved with the harvesting period and the first segment from spear tip. Appropriate harvesting is effective for higher asparagus yield and its bioactivity.  相似文献   

13.
Seeds from seven species of wild legumes of the South India were analyzed for proximate composition, mineral profiles, amino acid profiles of total seed protein, in vitro protein digestibility, and certain antinutritional factors to assess their potential as alternative sources of protein crops. The major findings of the study were as follows: crude protein ranged from 20.3 to 35.0%, crude lipid 3.1–9.6%, crude fiber 5.9–12.1%, ash 2.7–5.1%, and carbohydrates 49.2–61.8%. Minerals viz., sodium, potassium, calcium, magnesium, phosphorus, iron, copper, zinc, and manganese occurred in the range 42.9–135.9, 556.2–1639.5, 304.5–572.2, 174.9–686.7, 98.4–947.8, 3.6–16.4, 0.2–1.2, 2.0–30.0, and 1.0–3.9 mg/100 g seed flour, respectively. Profiles of amino acids of total seed proteins detected in the present study revealed that levels of valine, phenylalanine, tyrosine, isoleucine, and histidine of all the seven wild legume seed samples, threonine of Canavalia ensiformis and C. gladiata, leucine of Mucuna pruriens var. pruriens, and lysine of Cassia floribunda and C. obtusifolia were found to be higher than FAO/WHO (1991) requirement pattern. The in vitro protein digestibility of the legumes under study ranged from 63.39 to 83.32%. Antinutritional factors such as total free phenolics ranged from 0.41 to 5.96%, tannins from 0.04 to 0.60%, L-DOPA from 1.34 to 8.37% and trypsin inhibitor activity from 13.48 to 65.43 TIU/mg protein. The detected antinutritional factors probably have little nutritional significance if the seeds are properly processed.  相似文献   

14.
Results are given showing the effects of applying nitrogen, phosphorus, potassium, sodium and magnesium on the yield and mitieral composition of herbage cut repeatedly at the silage stage over a 3-year period. Grasses and clovers were separated before analysis. A combination of nitrogen and potassium was essential for the maintenance of high yields. Superphosphate did not increase dry-matter yields. 4 cwt. of common salt was ineffective, even under conditions of acute potassium deficiency; it reduced responses to potash and decreased yields when given with potash.
Ammonium sulphate and common salt greatly increased sodium uptakes and muriate of potash depressed them. Potassium contents were greatly reduced by repeated nitrogen applications and muriate of potash gave consistent and significant increases. Potassium-deficient grasses contained more sodium than potassium.
Ammonium sulphate increased magnesium contents and muriate of potash reduced them. There was a marked tendency for both effects to be more significant in late-season cuts. In late May the effects were small. 22 and 44 Ib. Mg/acre as magnesium sulphate had variable effects on herbage magnesium. These changes are discussed in relation to hypomagnesaemia.
None of the fertilizer treatments altered the calcium contents of either grass or clover.  相似文献   

15.
The spice,Aframomum danielli, on a wet weight basis with a moisture content of 10.5%, protein content of 8.2% (dry matter basis) and caloric value of 469.7 kcal/100 g, contains in varying amounts, minerals like calcium, magnesium, sodium, manganese, phosphorus, zinc and copper. Amino acids found in varying concentrations inA. danielli include L-Threonine, L-Serine, L-Valine, L-Proline, L-Glutamic acid, glycine, L-Leucine and L-Lysine. Using minimum inhibition zone of 20–22 mm in diameter,A. danielli inhibited the growth ofSalmonella enteriditis, Psudomonas fragi, Pseudomonas fluorescens, Proteus vulgaris, Streptococcus pyogenes, Staphylococcus aureus, Aspergillus flavus, A. parasiticus, A. ochraceus andA. niger. The minimum concentration (MIC) determined forKlebsiella pneumoniae andPseudomonas aeruginosa was 1 in 320 whilst the MIC forS. aureus was 1 in 8,000.  相似文献   

16.
Proximate composition, mineral element content, amino acid profile and the levels of some antinutrients in the edible leaves ofPterocarpus mildbraedii were determined. Moisture content was assayed as 85.12 percent (wet weight). Protein, fat, ash and fibre contents of the leaf (percent dry weight) were 25.84, 5.23, 6.44 and 7.56 respectively. Mineral element analysis showed high levels of calcium, potassium, magnesium, iron, copper, manganese and zinc. However, the level of sodium in the vegetable was low. Amino acid profile indicated that the leaf is rich in essential amino acids. The antinutrient levels of hydrogen cyanide and oxalate were low. The paper suggests the need to meet nutrient requirements through an increased use of this cheap but less popular food item with good nutritive potential.  相似文献   

17.
The protein, trypsin inhibitor (TI), tannin, phytate, phytic acid phosphorus and in vitro protein digestibility (IVPD) of cultivars of the African yambean (Sphenostylis stenocarpa) — AYB, pigeon pea (Cajanus cajan) — PP and cowpea (Vigna unguiculata) — CP were determined. The protein content of CP (24–28.0%) was higher than those of PP (21–22.5%) and AYB (21–22.5%). The cream and speckled AYB contained more TI (30.9 and 25.3 mg/g) than PP (7.5–14.1 mg/g) and CP (9.8–20.5 mg/g). Apart from the white CP cultivar, they contained more tannin (1.24–1.42 mg/g) than PP (0.14–0.97 mg/g) and AYB (0.71–1.17 mg/g). Phytate was lowest in the AYB (6.30–7.49 mg/g) than PP (8.31–11.31 mg/g) and CP (8.40–9.92 mg/g). Phytic acid contributed 67–74% of the phosphorous in the AYB, 66–75% in PP and 54–59% in CP. The IVPD of the AYB (73.3±0.7%) was significantly lower (p<0.05) than those of PP (76.34±0.2%) and CP (77.8±0.4%). There was a significant negative correlation between TI and IVPD (r=–0.63,p<0.05). There was no significant correlation between IVPD and phytate and tannin contents. There was a positive correlation between protein content and IVPD (r=0.69**) for the legumes under study. These legumes may pose no serious problems to populations consuming them especially when heat treatment is applied before consumption.  相似文献   

18.
Carotenoids and phenolic profile, antioxidant activity as well as concentrations of selected macronutrients (K, N, Mg, Ca and Na) and micronutrients (Zn, Cu and Mn) in flesh and peel of peach fruit were recorded at two harvest dates. Predominant mineral was potassium, followed by calcium, magnesium and sodium. The concentration of most micronutrients was greater in the peel than in the flesh especially in early season. The concentration of most elements in flesh and peel decreased during fruit maturation. Total carotenoids content varied with respect to the cultivar. β-cryptoxanthin and β-carotene were the major carotenoids in both tissues and flesh contain the lowest amounts. Neochlorogenic acid, chlorogenic acid, catechin, epicatechin, gallic acid, rutin, quercetin-3-O-galactoside, cyanidin-3-O-glucoside, cyanidin-3-O-rutinoside, were detected in both peel and flesh, with chlorogenic acid and catechin being the predominant components. Peel extracts showed markedly higher antioxidant activities, when estimated by ABTS or DPPH assays, than the flesh counterparts, consistent with the observed higher phenolic content. Overall, total phenolics levels increased at full ripening stage in both peel and flesh. The results found herein provide important data on carotenoids, phenolic and macro- and micronutrient changes during fruit growth, and emphases peach fruit as a potential functional food.  相似文献   

19.
Caffeine and theobromine contents (mg/g) weredetermined in samples of selected Nigerian beverageproducts. The beverages were cocoa (Milo, Bournvita,Rosevita and Enervita), coffee (Nescafe, Bongo, and Maxwell House decaffeinated) and tea (Lipton). The theobromine contentsof samples of Milo, Bournvita, Rosevita, Enervita, Nescafe, Bongo, Maxwell Housedecaffeinated coffee and Lipton were 62.10 ± 5.21, 64.80 ± 6.72, 82.80 ± 4.43, 80.37 ± 6.80, 27.00 ± 4.31, 14.67 ± 2.90, 23.46 ± 3.13 and 12.60 ± 1.52 respectively. The corresponding caffeine contents of these samples were 2.78 ± 0.43 (Milo), 3.17 ± 0.36 (Bournvita), 0.92 ± 0.51 (Rosevita), 1.05 ± 0.68 (Enervita),93.66 ± 8.91 (Nescafe), 6.47 ± 2.42(Bongo), 37.22 ± 5.34 (Lipton), and 0.21 ± 0.11 (Maxwell House decaffeinatedcoffee). Semi-processed cocoa beverages (Rosevita and Enervita) had significantly (p < 0.05) higher levels oftheobromine compared with the finished cocoas (Milo and Bournvita). Similarly, Nescafe contained significantly (p < 0.05) higher levels of caffeinecompared to Maxwell House (decaffeinated coffee) and Bongo. Levels of caffeine in Lipton tea were moderate.  相似文献   

20.
《Plant Production Science》2013,16(3):329-342
Abstract

In this study, we extended previous work linking the polarization of reflected light from crop canopies with characteristics of the canopy structure, such as the leaf inclination angle. We obtained reflectance and polarized reflectance in 8 spectral bands from the canopies of two varieties of wheat, planted in plots fertilized with a basal dressing and topdressed at the jointing and booting stages. The optical measurements were carried out on 3 clear-sky days when the plants were at the stem-elongation, heading and ripening stages, respectively. On each measurement date, we assessed the leaf orientation geometry of the plants using a Plant Canopy Analyzer (LAI-2000), measured the leaf greenness (an indicator of leaf chlorophyll content) using a handheld SPAD-502 (SPAD) optical sensor, and also measured plant height. Both polarization and leaf greenness observations at the heading stage were able to distinguish the canopies that had received topdressing from those without topdressing. However, no significant correlation was observed between the polarization in the blue, green and red bands and the SPAD (r = 0.425?0.456, n = 12 observations, p < 0.05). On the other hand, the mean leaf inclination angle (= mean tip angle: MTA) measured by the LAI-2000 was inversely correlated with the polarization in the 3 visible bands (r = ?0.85??0.88, n = 12, p < 0.001). Adjusting the view zenith angle according to the solar position at the time of measurement improved the accuracy. We tested a linear regression model to predict the MTA of the two wheat varieties based on polarized reflectance in the red band centered at 660 nm (r 2 = 0.73, n = 12, p < 0.001). Validation of this model obtained in the subsequent cropping season confirmed that polarization measurements were potentially useful for estimating the MTA of wheat stands in which the panicles were located below the topmost leaf layer of the canopy.  相似文献   

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