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我国宋代时期整体政治稳定、经济繁荣,人文发展得到空前提高,良好环境为我国饮食文化的繁荣奠定了基础。此时期的饮食文化中开始注重饮食营养的全面化,讲究食材烹饪的精细化。《菌谱》作为我国最早撰写的食用菌专著,是宋代对食用菌饮食的整理性文献。解读《菌谱》中食用菌的饮食文化,有助于通过结合食用菌饮食类别,研究宋代食用菌饮食文化的特征,这不仅可以了解当时人们的食用菌饮食习惯,更能折射出宋代食用菌文化的丰富。 相似文献
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海水中大量培养西藏拟溞及作为红鳍东方鲀鱼苗活饵料的研究 总被引:2,自引:0,他引:2
为了给北方海水鱼虾蟹苗提供一种新的活饵料,在海水中进行了大量培养西藏拟溞Daphniopsistibetana和将该溞投喂红鳍东方鲀Fugu rubripes的试验。结果表明:西藏拟溞培育的最高密度为1 570~2 320个/L,平均日产量为23.0~35.2 g/(m3.d);摄食西藏拟溞的红鳍东方鲀的存活率、体长和体重相对增长率与对照组差异不显著(P>0.05),饵料系数高于对照组,而日粮却与对照组接近;摄食西藏拟溞的红鳍东方鲀鱼体的高度不饱和脂肪酸(HUFA)中,除C22∶6ω3(DHA)的含量低于对照组外,其余脂肪酸的含量均高于或与对照组相当。同时也讨论了影响西藏拟溞密度和产量的生态因子及西藏拟溞的营养价值问题。 相似文献
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Butyrolactone I (BTL-I) is a butanolide isolated from the deep-sea-derived fungus, Aspergillus sp. It provides a potential new target for the prevention and treatment of food allergies. This study aimed to investigate the metabolic and pharmacokinetic profile of BTL-I in rats. The metabolic profiles were obtained by UHPLC–Q-TOF-MS. As a result, eleven metabolites were structurally identified, and the proposed metabolic pathways of BTL-I were characterized. The main metabolites were the oxidative and glucuronidative metabolites. In addition, a sensitive UHPLC–MS/MS method was established for the quantitation of BTL-I in rat plasma (LOQ = 2 ng/mL). The method was fully validated and successfully applied to the pharmacokinetic study of BTL-I in rats after oral administration or intravenous administration. The oral bioavailability was calculated as 6.29%, and the maximum plasma concentrations were 9.85 ± 1.54 ng/mL and 17.97 ± 1.36 ng/mL for intravenous and intragastric dosing groups, respectively. 相似文献
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Vasily I. Svetashev 《Marine drugs》2022,20(1)
Abyssal seafloor ecosystems cover more than 50% of the Earth’s surface. Being formed by mainly heterotrophic organisms, they depend on the flux of particulate organic matter (POM) photosynthetically produced in the surface layer of the ocean. As dead phytoplankton sinks from the euphotic to the abyssal zone, the trophic value of POM and the concentration of essential polyunsaturated fatty acids (PUFA) decrease. This results in pronounced food periodicity and limitations for bottom dwellers. Deep-sea invertebrate seston eaters and surface deposit feeders consume the sinking POM. Other invertebrates utilize different food items that have undergone a trophic upgrade, with PUFA synthesized from saturated and monounsaturated FA. Foraminifera and nematodes can synthesize arachidonic acid (AA), eicosapentaenoic acid (EPA), while some barophylic bacteria produce EPA and/or docosahexaenoic acid. FA analysis of deep-sea invertebrates has shown high levels of PUFA including, in particular, arachidonic acid, bacterial FA, and a vast number of new and uncommon fatty acids such as 21:4(n-7), 22:4(n-8), 23:4(n-9), and 22:5(n-5) characteristic of foraminifera. We suppose that bacteria growing on detritus having a low trophic value provide the first trophic upgrading of organic matter for foraminifera and nematodes. In turn, these metazoans perform the second-stage upgrading for megafauna invertebrates. Deep-sea megafauna, including major members of Echinodermata, Mollusca, and Polychaeta display FA markers characteristic of bacteria, foraminifera, and nematodes and reveal new markers in the food chain. 相似文献
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实现粮食安全战略与“双碳”目标是加快农业农村现代化步伐、加快建设农业强国的关键。为助推粮食安全战略与“双碳”目标的同步实现,本研究立足粮食安全视域,阐释生态低碳农业的科学内涵,厘清粮食安全与生态低碳农业的辩证关系,剖析粮食安全战略下生态低碳农业发展面临的问题与挑战,并针对性提出发展战略与推进路径。研究发现,在“大食物观”“大产业观”“大农业观”指导下,生态低碳农业涉及全食物品类、全产业流程、全生活环节。粮食安全是发展生态低碳农业的底线要求,生态低碳农业是可持续保障粮食安全的应有之义。当前,发展生态低碳农业面临自然资源约束、科学技术瓶颈、小农生产模式、居民观念局限等现实困难,亟需探索水地资源拓展、技术创新应用、居民素质提升等有效路径,推动生态低碳农业实现“藏粮于地”“藏粮于技”“藏粮于民”。 相似文献
48.
以明虾虾仁为研究对象,利用数值模拟结合实验验证的方法,研究两种送风方式(单侧送风和双侧送风)和两种载物方式(板带载物和网带载物)对虾仁冻结过程的影响,找到使虾仁冻结时间最短的送风和载物方式。研究发现:对于虾仁冻结来说,采用双侧送风+网带载物可以使虾仁表面流场流速更大,有利于提高换热效率,减少虾仁冻结时间,相对于其他送风方式和载物方式来说可缩短虾仁冻结时间的14%~25%;双侧送风有助于低速侧形成提高虾仁下表面流速的涡流,而网带载物可以避免在虾仁下侧面与网带交界处以及虾仁头部形成射流"真空区",上述均有助于提高虾仁表面风速,缩短虾仁冻结时长;但是冻结速度越快,虾仁冻结均匀性则越差。在本次实验中,虾仁内外最大温差出现在实验组D(双侧送风+网带载物),最大温差可达13.02℃。 相似文献
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Jianbo SHEN Qichao ZHU Xiaoqiang JIAO Hao YING Hongliang WANG Xin WEN Wen XU Tingyu LI Wenfeng CONG Xuejun LIU Yong HOU Zhenling CUI Oene OENEMA William J. DAVIES Fusuo ZHANG 《农业科学与工程前沿(英文版)》2020,7(1):5-13
Realizing sustainable development has become a global priority. This holds, in particular, for agriculture. Recently, the United Nations launched the Sustainable Development Goals (SDGs), and the Nineteenth National People’s Congress has delivered a national strategy for sustainable development in China—realizing green development. The overall objective of Agriculture Green Development (AGD) is to coordinate “green” with “development” to realize the transformation of current agriculture with high resource consumption and high environmental costs into a green agriculture and countryside with high productivity, high resource use efficiency and low environmental impact. This is a formidable task, requiring joint efforts of government, farmers, industry, educators and researchers. The innovative concept for AGD will focus on reconstructing the whole crop-animal production and food production-consumption system, with the emphasis on high thresholds for environmental standards and food quality as well as enhanced human well-being. This paper addresses the significance, challenges, framework, pathways and potential solutions for realizing AGD in China, and highlights the potential changes that will lead to a more sustainable agriculture in the future. Proposals include interdisciplinary innovations, whole food chain improvement and regional solutions. The implementation of AGD in China will provide important implications for the countries in developmental transition, and contribute to global sustainable development. 相似文献