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排序方式: 共有193条查询结果,搜索用时 15 毫秒
91.
Evaluation of protein digestibility-corrected amino acid score method for assessing protein quality of foods 总被引:5,自引:0,他引:5
G Sarwar F E McDonough 《Journal of the Association of Official Analytical Chemists》1990,73(3):347-356
The current concepts of protein quality evaluation were reviewed. A detailed examination of existing animal assays and more promising amino acid scoring methods has been carried out by an Ad Hoc Working Group on Protein Quality Measurement for the Codex Committee on Vegetable Proteins during the last 5 years. Several factors such as inadequacies of protein efficiency ratio (PER, the poorest test) and other animal assays, advancements made in standardizing methods for amino acid analysis and protein digestibility, availability of data on digestibility of protein and individual amino acids in a variety of foods, and reliability of human amino acid requirements and scoring patterns were evaluated. On the basis of this evaluation, amino acid score, corrected for true digestibility of protein, was recommended to be the most suitable routine method for predicting protein quality of foods for humans. Amino acid scores corrected for true digestibility of protein (as determined by rat balance method) were termed "protein digestibility-corrected amino acid scores." A detailed method for the determination of the protein digestibility-corrected amino acid score was proposed, and information about the range of scores to be expected in foods or food products was provided in the present investigation. The protein digestibility-corrected amino acid score method is a simple and scientifically sound approach for routine evaluation of protein quality of foods. Accuracy of the method would, however, be confirmed after validation with growth or metabolic balance studies in humans. 相似文献
92.
Mukhtar Ahmed Shakeel Ahmad Muhammad Tariq Zartash Fatima Zohra Aslam Muhammad Ali Raza 《Journal of plant nutrition》2020,43(6):896-920
AbstractWaste production is associated with human inhabitation and its rate is increasing over time. Globally, the major proportion of waste is disposed of through landfilling and open dumping, which is environmentally unsafe due to emission of greenhouse gases (GHGs). Thus, in order to avoid emission of GHGs from wastes it is important to use techniques that can convert wastes to energy/nutrients on eco-friendly economical way. Furthermore, quantification of the impacts of these waste management techniques on ecosystem is also needed through the application of tools like modeling, remote sensing, geographical information system (GIS), Unmanned Aerial Vehicles (UAVs) and life cycle assessments (LCA). Thus, this review was conducted by considering focus on potential of nutrient and energy recovery techniques from various types of wastes and approaches to enhance the efficiency of the process. The outcomes depicted that the aerobic and anaerobic digestion is suitable to deal with biodegradable and organic fraction of the waste, but anaerobic digestion seem to be more sustainable waste management techniques. Additionally, the review covers the techniques to drive energy and recover nutrient from non-biodegradable proportion. Different modern analytical tools; such as remote sensing, GIS and simple/dynamic models could be useful tool to help in the decision-making processes for waste managements. These tools can help us to design integrated solid waste management processes. Finally, we suggest that LCA should be considered to determine the environmental load of material/product from its production to final disposal (from cradle to grave). 相似文献
93.
94.
G Sarwar H G Botting R W Peace 《Journal of the Association of Official Analytical Chemists》1989,72(4):622-626
Amino acid profiles and/or protein digestibility (by the rat balance method) were determined for various forms (powder, ready-to-use, liquid concentrate, etc.) of cow's milk- and soy-based infant formulas obtained from 4 manufacturers. The essential amino acid data of the formulas were compared with that of human milk for the calculation of amino acid scores (based on the single most limiting amino acid). The product of amino acid score and total protein (g/100 kcal) was then termed "amino acid rating." Amino acid scores for the milk- and soy-based formulas ranged from 59 to 90 and from 59 to 81%, respectively, due to deficiencies in sulfur amino acids and/or tryptophan. Because of significantly higher total protein contents (g/100 kcal) of soy- (2.65-3.68) and milk-based (2.20-2.95) infant formulas compared to human milk (1.5), the relative amino acid ratings (human milk = 100) for all infant formulas except 2 liquid concentrates (having values of 87%) were above 100%. Values for true digestibility of protein in milk- and soy-based formulas ranged from 87 to 97 and from 92 to 95%, respectively. When corrected for protein digestibility, the relative amino acid ratings for all the milk-based liquid concentrates were below 100% (77-98%). 相似文献
95.
96.
This paper presents the results of modelsimulations to evaluate drainage designparameters for the Fourth Drainage Project(FDP), Punjab, Pakistan. The SWAP model wasapplied to compute the effects of landdrainage (12 combinations of drain depthand spacing) on soil moisture conditions inthe root zone and their effect on cropyield and soil salinization. For theconditions considered, the selection ofdrain depth is found to be more criticalthan that of drain spacing. Deeper drainsperform technically better in relation tocrop growth and soil salinization. Theoptimum drain depth for the multiplecropping system of the FDP-area was foundto be 2.2 m. This drain depth will producereasonably good crop yields at rather lowdrainage intensity while keeping the rootzone salinity within acceptable limits.This drainage design also maintained thegroundwater table depth below the root zonethroughout the growing season. The outcomeof this study reveals that the drainagedesign criteria applied for the FDP israther conservative with high drainageintensity. The FDP-area can effectively bedrained with a 25 percent lower drainageintensity (q
drain/h)provided no operational or maintenanceconstraints are present. However, the finaldecision on the optimum combination ofdrain depth and drain spacing would requirea thorough economical analysis. Thenon-steady state approach proved successfulin analyzing the complex interactionsbetween irrigation and drainage components.It is a valuable tool to optimize thedesign of drainage systems against cropyields and soil salinization. 相似文献
97.
A rotational water supply system is designed to deliver a constant flow of water among irrigators along a tertiary canal. Under the existing rotational system in Pakistan transmission losses along the canal are not considered. A constant time per unit irrigated area is allocated to all the farmers regardless of their location along the canal. This results in decreasing volumes of water delivered to downstream farmers. A variable time model is developed which allocates more time to the downstream farmers to deliver a constant volume of water per unit area to all the farmers in the command area of a tertiary unit. 相似文献
98.
Relationship of age to body weight,scrotal circumference,testicular ultrasonograms,and semen quality in Sahiwal bulls 总被引:1,自引:1,他引:0
Ahmad Ejaz Ahmad Nasim Naseer Zahid Aleem Muhammad Khan Muhammad Sarwar Ashiq Muhammad Younis Muhammad 《Tropical animal health and production》2011,43(1):159-164
The objective of the present study was to determine the relationship of age to body weight (BW), scrotal circumference (SC),
number of pixels of testicular ultrasonograms (NP), and semen quality in Sahiwal bulls. The study was based on 128 Sahiwal
bulls of different age groups (from 0 to >100 months of age). Bulls were evaluated for SC, BW, and NP. Semen was evaluated
once a week for five consecutive weeks from regularly collected donor bulls (n = 86) ranging in age from 25–30 to >100 months. Ejaculate volume, sperm motility, sperm concentration, sperm morphology,
percent live sperms, sperm plasma membrane integrity, and normal acrosome were compared among different age groups. Mean SC
and BW increased (P < 0.05) in a curvilinear manner from birth to >100 months of age. Mean NP of testicular ultrasonograms increased (P < 0.05) from 0 to 24 months and then plateaued until >100 months of age. Body weight, SC, and NP were positively correlated
with age from birth until >100 months (r = 0.91, 0.87, and 0.40, respectively). Ejaculate volume (5.7 ± 0.2 vs. 4.6 ± 0.09 ml) and sperm concentration (1,281.6 ± 17.7
vs. 1,115.8 ± 55.9 × 106/ml) increased (P < 0.05) in mature bulls compared to younger ones. However, motility (68.6 ± 0.3%), plasma membrane integrity (50.8 ± 1.0%),
and normal acrosome (74.8 ± 0.5%) remained insignificant due to age. In six of eight age groups studied, morphological abnormalities
were well within the range (18.1 ± 0.3%). In conclusion, the BW, SC, and NP of testicular ultrasonograms, ejaculate volume,
and concentration increased with age. Moreover, semen quality is fairly independent of age except volume and concentration
in Sahiwal bulls. 相似文献
99.
The experiment was conducted to investigate the influence of maize (Zea mays), sorghum (Sorghum bicolor) and millet (Pennisetum americannum) silages with or without concentrate on nutrients intake, digestibility, nitrogen balance and weight gain in Sipli sheep. Six experimental diets were formulated having 100% maize silage (MS), maize silage and concentrate as 50:50 (MSC),
100% sorghum silage (SS), sorghum silage and concentrate as 50:50 (SSC), 100% millet silage (MiS) and millet silage and concentrate
as 50:50 (MiSC), respectively. For this purpose, 24 Sipli lambs were randomly allotted to six experimental diets in a completely randomized design for 90 days, four lambs per diet.
The results indicated that among various silage diets, lambs fed MS diet consumed higher dry matter (DM) than those fed SS
and MiS diets. Likewise, lambs offered MSC had higher dry matter intake than those fed SSC and MiSC diets. Crude protein (CP)
and neutral detergent fibre (NDF) consumed by the lambs also followed the similar trend. Higher DM, CP and NDF digestibilities
were also observed in lambs fed MS and MSC diets than those fed SS, SSC, MiS and MiSC diets. Overall digestibilities of DM,
CP and NDF were higher in experimental diets containing silage with concentrate. Lambs fed MS diet had 2.79 g/day and 4.45 g/day
higher N retention than those fed SS and MiS, respectively. Similarly, lambs fed MSC diet had 2.24 g/day and 5.12 g/day higher
N retention than those fed SSC and MiSC diets, respectively. The results showed that lambs fed MSC gained more daily weight
gain had better feed conversion ratio than those fed MS, SS, SSC, MiS and MiSC diets. The findings of the present study indicated
that lambs fed MSC diet had higher nutrients intake, digestibility, nitrogen balance and weight gain. 相似文献
100.
Abdulaziz Rabiu Abdulkadir Dhiya Dalila Zawawi Md Sarwar Jahan 《Russian Agricultural Sciences》2016,42(1):34-36
Lack of proper nutrition is one of the most serious problem across the globe, affecting majorly African countries, where many children died not only due to inadequate food but also as a result of insufficient nutrient in their diet. This research was aimed to study the proximate composition and screening of chemical components in different part of Moringa oleifera Lam. Proximate analysis was adapted from the standard methods developed by Association of Official Analytical Chemists (AOAC). We have determined percentage of moisture content, ash content, crude protein, crude fibre, crude fat and carbohydrate which were ranges from 8.1–4%, 5.59–9.28%, 11.70–26.57%, 21.03–44.27, 11.82–20.19 and 8.16–31.12% respectively. Different bioactive compounds of polyphenol, flavonoids, tannins and saponin were determined. Different parts of plants accumulate different levels of polyphenol, flavonoids, tannins and saponin. Our study suggest that Moringa oleifera can served as a good supplement to our nutrition, due to high content of fibre, protein, fat. However intake of Moringa plant might reduce the risk of many oxidative related problems due to the present of some polyphenols and flavonoid in almost all part of the plant used. 相似文献