富硒绞股蓝功能性茶冻的研制

绞股蓝是一种药食同源的草本植物,被誉为“南方人参”,兼备了较高的营养价值与药用价值,具有清热解毒、调节血糖血脂、改善记忆力、抗动脉硬化、抗心肌梗塞、预防癌症等功效。然而,目前绞股蓝相关产品仍以绞股蓝茶为主,存在味苦、浮沫多的弊端,成为绞股蓝推广销售的主要瓶颈问题。本论文以陕西安康所产富硒超微绞股蓝茶粉为主要原料,以魔芋葡甘聚糖、黄原胶、甜味剂等为辅料,以感官评价为主要指标,利用正交试验与Box-Benhnken设计-响应面法筛选出最优的富硒绞股蓝功能性茶冻配方工艺。相较于传统绞股蓝茶,所得产品(1)克服了绞股蓝茶味苦、浮沫多的弊端,丰富了绞股蓝茶产品形式;(2)茶冻状态突破了传统茶冲泡形式下功能成分利用率低的限制,极大提高了硒等功能活性物质的摄取率;(3)以膳食纤维-魔芋葡甘聚糖为成胶成分,既使产品具有细腻、弹爽的口感、透明均匀的色泽,同时赋予其调节肠道菌群、缓解便秘的功能特性,显著增强了产品的功能活性;(4)以甜味剂代替传统茶冻中的蔗糖, 更适于控糖人群和代谢综合症人群食用。该研究结果为绞股蓝基功能性产品的研制与推广提供了技术和理论借鉴。     

小麦富硒生产技术研究

通过国家发明专利产品——富硒增产素（ZL96107830.8）在小麦上的应用，生产出人类理想的天然富硒小麦，进而加工成品种多样的天然富硒保健食品，使硒进入食物链，实现安全、方便、经济地给人体补硒，将从根本上解决人畜缺硒状况，从而提高中华民族的健康水平，造福人类，实属一项绿色保健型农业新技术。为了生产富硒小麦，笔者以叶面喷施的方式在小麦拔节期、灌浆初期和灌浆中期喷施硒液肥，探索硒液肥对小麦籽粒硒含量的影响，结果表明：小麦籽粒中硒含量高于对照3倍左右。     

安康富硒食品特色农业产业集群发展的SWOT分析

陕西省安康市富硒食品特色农业产业开发显现出良好态势,已形成初级形态的特色农业产业集群雏形.文章运用SWOT分析方法,分析了安康市富硒食品产业集群发展的内在优势和劣势、外在机会和威胁,并提出了相应的发展战略和对策建议.     

嗜金微生物研究概况

在广泛文献检索基础上,对嗜金微生物的种属、富集黄金的机理、工业应用价值及潜力进行了概述,为进一步对其开发利用提供科学资料。     

基于多项式回归分析的摩尔多瓦葡萄富硒效应

[目的]探讨基于多项式回归分析的摩尔多瓦葡萄富硒效应,为开展广西富硒土原位生产富硒葡萄提供参考依据.[方法]以摩尔多瓦葡萄为试验材料,采用三元二次饱和D-最优设计,以石灰石粉(x1)、AM菌剂(x2)、营养调节剂(x3)为因变量,以试验结果中葡萄硒含量为自变量(y),设11个处理(处理1~处理11),经回归分析明确试验因素对葡萄硒含量的影响,优选生产富硒摩尔多瓦葡萄的外源物质施用量.[结果]施用石灰石粉、AM菌剂和营养调节剂各处理(除处理1外)摩尔多瓦葡萄的硒含量比对照(CK)提高1.1~1.8倍,最高增幅达87.2%.多项式回归方程中单因素效应分析结果显示,当石灰石粉、AM菌剂和营养调节剂施用量分别为2400.00、69.00和39.98 kg/ha时,摩尔多瓦葡萄硒含量最高,为11.56μg/kg;互作效应分析结果显示,两两互作对摩尔多瓦葡萄硒含量的影响排序为x1x3>x1x2>x2x3.[结论]摩尔多瓦葡萄分别开沟施用石灰石粉、AM菌剂和营养调节剂2400.00、69.00和39.98 kg/ha,其果实硒含量达富硒水平.因此,施用石灰石粉、AM菌剂和营养调节剂等外源物质可作为生产富硒葡萄的新型技术手段.     

略论骆驼的耐干渴能力

荒漠水源奇缺,常有干渴威协。骆驼长期在这种自然选择下,造就出一种十分惊人的耐干渴能力,十日不饮可照常供使役,30～40日内缺水不致有生命危险。据研究认为,骆驼高度耐渴的机理主要在于:一次能饮入60～80升甚至更多的水;能饮用含盐量相当高的水;血液和体液中保存水的能力很强;能节约散热、呼吸、排尿、排粪过程中的水份消耗;有较高排泄浓缩尿的能力;可有效利用体内的代谢水;即使高度失水(达体重的30%)也能短期耐受过去。正因其耐渴能力强,所以才使人类开发利用荒漠成为可能;使大面积缺水草埸和其它家畜所不能利用的灌木类植物得到合理利用;还能在缺水条件下持续分泌稀薄的低脂肪驼乳,为沙漠旅行者提供上等饮料。     

Dietary intake of iodine‐enriched eggs decreases the incidence of mouse mammary tumors caused by the activated ErbB2 oncogene

Human epigenetic studies suggest that consumption of seaweed prevents mammary cancer, which possibly is explained by iodine daily intake. In this study, we evaluated the efficacy of dietary intake of iodine‐enriched eggs on mammary tumor incidence caused by the expression of activated type ErbB2. Female transgenic mice were divided into three groups, and fed a basic diet, a diet supplemented with ordinary eggs, or with iodine‐enriched eggs. The number of mammary tumors greater than 5 mm in diameter was recorded in mice at 6 months of age. We report that the average number of mammary tumors per mouse was significantly lower in the iodine‐enriched egg‐added diet group than in either the basic diet or ordinary egg diet groups. These results indicate that iodine intake through livestock‐derived products can reduce the incidence of mammary cancers caused by the expression of activated type ErbB2.     

亲和素磁珠分离毛竹SSR标记方法的优化

在参考其它文献报道的基础上,构建毛竹SSR位点富集文库。用EcoRⅠ分别和DraⅠ、EcoRⅤ、SmaⅠ、PvuⅡ四种平端限制性内切酶对毛竹基因组DNA进行双酶切,酶切片段回收后与根据抑制性PCR原理设计的接头连接。在利用亲和素磁珠富集含有SSR序列的DNA片段过程中,对杂交、漂洗及洗脱步骤进行优化。通过三引物特异PCR筛选含有SSR序列的阳性克隆并结合测序结果对富集SSR文库进行评价,确定了一条简单、经济、高效分离竹类植物SSR标记的方法。     

Traditional fallows in Latin America

Traditional fallow systems of Latin America have not been extensively studied from either a socioeconomic or biophysical viewpoint. Only in the past decade have some of these systems — modified shifting cultivation in the Amazon, the bracatinga (Mimosa scabrella) fallow of southeastern Brazil, the babassu (Attalea spp.) system of the Amazon margins, and short bush fallows mostly for Phaseolus bean (the so-called frijol tapado) — received any attention. Over the past century, traditional cultivators have adopted several legumes such as Mucuna spp., Lathyrus nigrivalis, Canavalia spp., and Senna guatemalensis as green manures or managed fallows in food crop production systems, which have recently been the object of studies by social and biological scientists. Longer, monospecific fallows involving woody legumes have been studied to varying degrees. The legumes include Senna guatemalensis, Mimosa tenuiflora, and Gliricidia sepium. Systems in which crop production is alternated with animal grazing of secondary vegetation include the caatinga of Northeast Brazil, the espinales of Chile, the matorrales of northern Mexico, and the chaco of Argentina, Paraguay, and Bolivia. A classification is proposed depending on the nature of the species (woody or nonwoody) and their composition (mono- or multispecies) and land management (burned or not). Much work is still needed in more complete characterization, determination of economic importance and potential, understanding the relationships among components, studies of nutrient cycling, and verification of the effects of shorter fallow periods of these systems.This revised version was published online in November 2005 with corrections to the Cover Date.     

Turnover of Se in adequately fed chickens using Se‐75 as a tracer

Inorganic selenium (Se) in the form of selenite is applied to livestock to avoid Se deficiency. Selenite is, however, an artificial Se source in diets of unsupplemented chickens. It is therefore hypothesized that organic Se sources, such as Se‐enriched yeast and wheat, could be a more suitable Se supply in animal nutrition, although information on the transition of Se from organic Se sources in fast‐growing chickens is scarce. In this work, chickens were fed a low Se diet (0.27 ± 0.01 mg Se/kg, Se‐enriched yeast) until 20 days of age, after which the Se concentration was increased to maximum concentration allowed by the poultry industry in Europe (0.5 p.p.m. Se). At the same time, a daily contribution of carrier‐free ⁷⁵Se tracer from labelled wheat was administered from day 20 to 27. The chickens showed S and Se homeostasis, as the concentration of S and Se in liver, blood or kidney remained about constant, and steady state of S and Se in the other organs was reached 1 day after the diet shift. The uptake of ⁷⁵Se was readily seen in all organs. After 1 week, the depuration of the ⁷⁵Se tracer was followed, and biological half‐lives and retention in individual organs were determined. The shortest biological half‐lives were observed in major metabolic organs, the liver, kidney and pancreas with half‐lives close to 4 days. There was a significant (p < 0.05) uptake in lung, brain and muscle that reached steady state when the administration of ⁷⁵Se was terminated. The half‐life of ⁷⁵Se in heart was 9 days and 7 days in blood. The longest half‐lives were observed in muscle (12 days), brain and lungs (13 days). All half‐lives were shorter than in Se deplete animals.