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1.
为探究江苏省长荡湖、固城湖、高邮湖、洪泽湖、太湖、阳澄湖6个不同地理湖泊中华绒螯蟹(Eriocheir sinensis)群体的氨基酸组成及其对应的营养品质评价,本研究采用OPA-FMOC柱前衍生化HPLC法测定中华绒螯蟹肌肉组织中氨基酸组成及含量,并根据联合国粮食及农业组织/世界卫生组织(FAO/WHO)标准对其进行营养品质评价。结果显示:所有样本均检测出17种常见氨基酸,各群体间氨基酸含量差异显著;雌雄群体各氨基酸指标均符合FAO/WHO标准模式。雌蟹中,总必需氨基酸(EAA)、总非必需氨基酸(NEAA)、总氨基酸(TAA)、必需氨基酸指数(EAAI)均为洪泽湖、固城湖群体显著高于长荡湖、太湖、阳澄湖群体,与高邮湖群体差异不显著。雄蟹中,高邮湖群体各氨基酸指标均显著高于阳澄湖、洪泽湖、太湖群体,与长荡湖,固城湖群体差异不显著;主成分分析和聚类分析结果与其氨基酸指标差异相似,雌雄群体综合判别准确率分别为79.20%、95.80%。综上,江苏6个地理湖泊中华绒螯蟹雌雄群体肌肉组织中氨基酸种类齐全,氨基酸含量存在显著性差异,且氨基酸之间的比例适宜,均为优质或良好蛋白源,基于中华绒螯蟹群体间的氨基酸含量差异可对其群体进行有效的判别。  相似文献   
2.
本文对野生大豆种质资源的起源、新型应用、以及未来发展进行了阐述。对其遗传性状进行了简单分析,并从国内分布的地理位置、种质资源发展所需要面对的一些问题进行了探讨。为野生大豆资源的相关研究提供参考。  相似文献   
3.
综述皱木耳Auricularia delicata新品种"鹿肚耳"的形态特征和食用特点,测定其与黑木耳、毛木耳、毛木耳白色变种"玉木耳"人工栽培子实体的基本营养成分、矿质元素含量和氨基酸组成,评价其营养价值。结果表明:鹿肚耳热量235 kJ/100g、蛋白质7.21 g/100g、脂肪1.5 g/100g、碳水化合物48.4 g/100g、总膳食纤维29.3g/100g,含有5种常量元素、5种必需微量元素,其中,硒元素含量是黑木耳的4.6倍;含有人体所需的8种必需氨基酸,氨基酸化学评分(CS)和氨基酸评分(ASS)分别为12和18.86,色氨酸为其限制性氨基酸;蛋白质综合评价低于其他3种木耳。  相似文献   
4.
In this study, the yields, nutritional qualities and nitrate (NO3) content of Chinese kale were studied with two cultivars, following partial replacement of nitrate (20%) with ammonium (NH4), urea and glycine in hydroponics. The results showed that, compared with the full nitrate treatment, ammonium replacement increased the fresh weight by 18.1% and 8.0% of ‘Zaobao’ and ‘Lvbao’ cultivars respectively, whereas urea and glycine replacements decreased the biomass significantly. Adding different nitrogen (N) forms significantly improved the contents of vitamin C, soluble sugar, free amino acid, protein, soluble phenol and flavonoids in Chinese kale. Adding the three alternative N forms also reduced nitrate content significantly, in which glycine replacement was the lowest. According to the results obtained, different forms of N replacement could be used for different purposes. Glycine replacement could be the best alternative only to improve qualities, while ammonium replacement could be the best alternative to improve both the yield and qualities.  相似文献   
5.
Long-term studies are valuable in assessing the impact of crop management practices on soil sustainability and function. This study used two calculation scenarios, fixed depth and Equivalent Soil Mass (ESM) to assess (i) soil nutrient status and (ii) soil organic carbon (SOC) after 50 years of nitrogen (N) fertilizer application rates (0, 22, 45, and 67 kg N ha?1) and tillage [clean tillage (CT), reduced tillage (RT), and no-tillage (NT)] in a dryland winter wheat-sorghum-fallow cropping system. The soil organic matter (SOM) content increased by 33% with NT and RT compared with CT. The SOC at 0–30 cm was 39% greater than 30–60 cm depth with both fixed depth and ESM calculations. Soil nutrient specifically soil calcium (Ca), magnesium (Mg), and phosphorus (P) associated with N rates were no different than the control. Crop nutrient removal may eventually reduce soil nutrient contents with only N application. Nutrient addition specifically P should be considered in the future.  相似文献   
6.
Increasing the amount of nutrients in plant-based foods will help to improve the nutritional status of people in the World. Faba bean (Vicia faba L.) as a staple food in developing countries has the potential to provide many nutrients in human diets. The objective of this study was to characterize the nutrient concentrations in leaf, pod, and seed of faba bean varieties. A field study was conducted with six faba bean varieties. Variation in the elemental concentrations of nutrients and protein occurred among varieties and different parts of the plants. The highest concentrations of nitrogen, phosphorus, potassium, zinc, or copper and protein were in the seeds. However, the highest accumulation of calcium, magnesium, iron, or manganese was in the leaves. We recommend that faba bean can be considered as a valuable crop in the diet of nutrient-deficient consumers due to high concentration nutrients in edible parts of the plant.  相似文献   
7.
李天奇 《林业科技情报》2020,52(1):53-54,57
在黑龙江盘中自然保护区区位、用地和资源的现状分析基础上,对保护区进行类型划分,确定保护区主要保护对象和规划目标,划分出保护区的核心区、缓冲区、实验区三大功能区域的范围和面积,进而再对保护区的规划管理设施和规划管理措施进行总体探讨,从而保证黑龙江盘中自然保护区的可持续发展。  相似文献   
8.
Trout and charr, members of the salmonid family, have high conservation value but are also susceptible to anthropogenic threats in part due to the specificity of their habitat requirements. Understanding historical and future threats facing these species is necessary to promote their recovery. Of freshwater trout and charr in the Canadian Rocky Mountain region, westslope cutthroat trout (Oncorhynchus clarkii lewisi), bull trout (Salvelinus confluentus; a charr species) and Athabasca rainbow trout (Oncorhynchus mykiss) are of conservation concern. And indeed, range contractions and declining populations are evident throughout much of their ranges. Range contraction was most evident in the southern Alberta designatable unit (DU) of westslope cutthroat trout. Diminished populations were also evident in the downstream watersheds of the Alberta bull trout range, and throughout the Athabasca rainbow trout range. We assessed historical and future threats to evaluate the relative importance of individual threats to each DU and compare their impact among species. Individual threats fall into the broad categories of angling, non-native species and genes, habitat loss and alteration, and climate change. Severity of each threat varies by DU and reflects the interaction between species’ biology and the location of the DU. Severity of threats facing each DU has changed over time, reflecting extirpation of native populations, changes in management and industry best practices, expansion of non-native species and progressing climate change. The overall threat impact for each DU indicates a high probability of substantial and continuing declines and calls for immediate action.  相似文献   
9.
对我国食用菌产业发展现状进行梳理,指出我国食用菌行业主要存在的问题不仅是开发规模小、科技含量低,而且品种质量参差不齐、销售渠道不畅、食用菌产品存在滞销等。构建面板数据模型探究影响我国食用菌产业升级的主要影响因素,结果表明,食用菌年度生产总量、食用菌行业从业人员总数、出口贸易总额、固定资产投资、居民消费支出水平与食用菌产业结构升级之间为显著的正相关关系,基于此提出了助力我国食用菌产业升级的政策。  相似文献   
10.
为寻求应用于肉制品加工的亚硝酸盐替代物,以中式香肠为研究对象,从感官评价、营养成分及挥发性风味物质组成探究不同发色剂(试验组1:0.5%甜菜粉+50 mg·kg-1亚硝酸钠、试验组2:0.1%甜菜粉+0.06%改性血红蛋白、试验组3:100 mg·kg-1亚硝酸钠)对产品营养和风味品质的影响。结果表明,试验组1和2香肠的外观、色泽和口感与试验组3差异不显著,且均与对照组差异显著(P<0.05);试验组1氨基酸总含量显著高于其他组(P<0.05);试验组2脂肪酸含量相对最高,其中十八碳二烯酸含量显著高于其他各组(P<0.05);通过风味分析,试验组1、试验组2分别检出27、26种挥发性成分,风味物质种类多于试验组3,其中试验组2醛类、酯类化合物含量相对较高,风味更好。本研究结果为中式香肠加工过程中亚硝酸盐的有效替代,提升中式香肠品质提供了一定的技术指导。  相似文献   
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