纤维素酶对玉米秸青贮营养成分及其奶牛瘤胃降解率的影响

本研究探讨了添加纤维素酶制剂对玉米秸青贮营养成分含量变化及其瘤胃内降解率的影响。以去穗玉米秸为试验材料,分别以0.00 g/1kg(C)、0.05g/1kg(Ⅰ)、0.2g/1kg(Ⅱ)、1g/1kg(Ⅲ)进行添加纤维素酶,贮藏4周后进行常规营养成分含量变化分析和饲养试验。用4头装有永久性瘘管荷斯坦乳牛,按4×4拉丁方设计进行瘤胃内降解率的试验。结果为:Ⅰ组、Ⅱ组和Ⅲ组玉米秸青贮DM含量差异不显著,但均显著低于C组;不同处理组的玉米秸青贮CP含量随纤维素添加量增加而显著提高,以1g/1kg纤维素酶添加处理的提高幅度最大;NDF和ADF含量均随着纤维素添加量增加而显著下降,其中1g/1kg纤维素酶添加处理的下降幅度最大。Ⅲ组、Ⅱ组和Ⅰ组玉米秸青贮的DM和CP奶牛瘤胃有效降解率均显著高于C组,并且Ⅲ组显著高于Ⅱ组和Ⅰ组;不同处理组的玉米秸青贮NDF有效降解率之间差异显著,Ⅲ组>Ⅱ组>Ⅰ组>C组;玉米秸青贮ADF有效降解率Ⅲ组、Ⅱ组和Ⅰ组之间无显著差异,但均显著高于C组。表明纤维素酶处理能提高青贮营养价值,且纤维素酶以1g/1kg添加量为宜。     

豆番粉与玉米粉对人体血糖胰岛素胰升血糖素的影响

目的探讨豆番粉和玉米粉对人体餐后血糖、胰岛素、胰升血糖素的影响。方法选择Ⅱ型糖尿病人、肥胖人、健康人，ｄ１均进食面粉，ｄ２随机进食豆番粉或玉米粉，测量２ｄ的空腹血糖及餐后３０、６０、１２０、１８０ｍｉｎ各５个时点的血糖、胰岛素、胰升血糖素值。结果糖尿病人进食豆番粉后６０、１２０、１８０ｍｉｎ的血糖值低于进食面粉，Ｐ分别＜０．０１、０．０１、０．０５；进食玉米粉后１２０、１８０ｍｉｎ血糖值低于面粉，Ｐ＜０．０５。２种实验食物的血糖增值面积均低于面粉，Ｐ＜０．０５；进食豆番粉后各时点胰岛素值、胰升血糖素值明显低于进食面粉，Ｐ＜０．０５或＜０．０１；进食玉米粉后同时点胰岛素值与面粉相比无显著性差异，胰升糖素值３０、１２０ｍｉｎ有显著性差异。肥胖人进食豆番粉后血糖值与面粉相比无显著性差异，但胰岛素值、胰升血糖素值有明显下降，各时点值Ｐ均＜０．０５。结论①豆番粉血糖指数低，可控制餐后高血糖状态，不增加胰岛素、胰升血糖素分泌，可减轻胰岛素抵抗。②玉米粉血糖曲线增值面积、低于面粉，可作为糖尿病人选择的食品，对改善胰岛素抵抗也有较好的作用。     

Multinutrient Biofortification of Maize (Zea mays L.) in Africa: Current Status,Opportunities and Limitations

Macro and micronutrient deficiencies pose serious health challenges globally, with the largest impact in developing regions such as subSaharan Africa (SSA), Latin America and South Asia. Maize is a good source of calories but contains low concentrations of essential nutrients. Major limiting nutrients in maize-based diets are essential amino acids such as lysine and tryptophan, and micronutrients such as vitamin A, zinc (Zn) and iron (Fe). Responding to these challenges, separate maize biofortification programs have been designed worldwide, resulting in several cultivars with high levels of provitamin A, lysine, tryptophan, Zn and Fe being commercialized. This strategy of developing single-nutrient biofortified cultivars does not address the nutrient deficiency challenges in SSA in an integrated manner. Hence, development of maize with multinutritional attributes can be a sustainable and cost-effective strategy for addressing the problem of nutrient deficiencies in SSA. This review provides a synopsis of the health challenges associated with Zn, provitamin A and tryptophan deficiencies and link these to vulnerable societies; a synthesis of past and present intervention measures for addressing nutrient deficiencies in SSA; and a discussion on the possibility of developing maize with multinutritional quality attributes, but also with adaptation to stress conditions in SSA.     

玉米粉水解物作为红霉素发酵培养基的研究

研究了摇瓶试验中玉米粉水解物替代葡萄糖发酵红霉素的最佳培养基组成。用均匀设计法得到发酵基础培养基的最佳配比(wB，％)：玉米粉3．6，黄豆饼粉2．0，玉米浆0．23，碳酸钙0．5，淀粉0．6；用正交试验得到了优化的补混合料配比(％)：玉米粉4．5，黄豆饼粉2．0，硫酸铵1．0，酵母粉2．0；并得到了玉米粉的最适水解条件。30t发酵罐放大实验结果表明，用玉米粉水解物替代葡萄糖作碳源发酵红霉素，发酵单位提高5．8％，综合生产成本降低26．0％。     

A Fumonisin Prevention Tool for Targeting and Ranking Agroclimatic Conditions Favoring Exposure in French Maize-Growing Areas

The levels of fumonisins (FUMO)—mycotoxins produced by Fusarium verticillioides—in maize for food and feed are subject to European Union regulations. Compliance with the regulations requires the targeting of, among others, the agroclimatic factors influencing fungal contamination and FUMO production. Arvalis-Institut du végétal has created a national, multiyear database for maize, based on field survey data collected since 2003. This database contains information about agricultural practices, climatic conditions and FUMO concentrations at harvest for 738 maize fields distributed throughout French maize-growing regions. A linear mixed model approach highlights the presence of borers and the use of a late variety, high temperatures in July and October, and a water deficit during the maize cycle as creating conditions favoring maize contamination with Fusarium verticillioides. It is thus possible to target a combination of risk factors, consisting of this climatic sequence associated with agricultural practices of interest. The effects of the various possible agroclimatic combinations can be compared, grouped and classified as promoting very low to high FUMO concentrations, possibly exceeding the regulatory threshold. These findings should facilitate the creation of a national, informative and easy-to-use prevention tool for producers and agricultural cooperatives to manage the sanitary quality of their harvest.     

气候变暖对阿勒泰地区春玉米播种期和种植布局的影响--测试文章

采用阿勒泰地区7个气象站1961—2010年逐日平均气温资料，使用线性趋势分析、累积距平、t检验并基于Kriging插值法，分析近50年日平均气温稳定通过≥10℃的初日、终日、持续日数和积温的时空变化特征，揭示春玉米播种期及种植布局的变化规律。结果表明，阿勒泰地区近50年≥10℃积温呈现初日提前、终日推迟、持续日数延长、积温增加的现象，其倾向率分别为0.3、1.3、1.6 d·10a^-1和57.1℃·10a^-1，且突变年份均发生在20世纪90年代中期。各县市春玉米播种期提前3～8 d，生长季延长6～11 d。突变前青河东部不能种植春玉米，晚熟品种不能种植或种植风险较大。随着气候不断变暖，春玉米不同熟性品种可种植区逐渐东扩，各县市春玉米在品种熟性上均发生了改变，表现为由不能种植到种植早熟、早熟向中（晚）熟、中晚熟向晚熟品种的变化。     

玉米/鹰嘴豆间作条件下不同施磷量对灌耕灰钙土无机磷组分的影响--测试文章

在甘肃引黄灌区的灌耕灰钙土区域,通过玉米/鹰嘴豆间作种植,采用蒋柏藩、顾益初石灰性土壤无机磷分级方法研究了施磷水平和间作种植方式对玉米、鹰嘴豆土壤无机磷素形态的影响。结果表明：研究区各无机磷形态含量顺序为O-P＞Ca₁₀-P＞Ca₈-P＞Al-P＞Fe-P＞Ca₂-P,施磷能够显著提高玉米和鹰嘴豆土壤中Ca₂-P、Ca₈-P、Al-P和Fe-P的含量,O-P和Ca₁₀-P的含量不随施磷量增加发生显著性变化;与单作相比,间作种植对鹰嘴豆土壤带各无机磷组分含量没有显著影响,但间作玉米种植带土壤各组分无机磷含量均低于单作土壤,其中不施磷肥处理下Fe-P、施纯磷 40 kg·hm^-2处理下Al-P及施纯磷 80 kg·hm^-2处理下Ca₁₀-P的含量显著低于单作土壤。     

不同切碎长度和发酵方式对全株饲用谷子青贮质量的影响

本研究旨在探索不同切碎长度和发酵方式对全株饲用青贮谷子质量的影响。采用2×3双因子试验设计,切割长度分别为1.5 cm、2.5 cm和3.5 cm,发酵方式分为复合菌剂发酵和乳酸菌发酵两个类型,每处理3个重复。常温发酵40 d后取样,进行感官评定,分析基础养分,测定挥发性成分。结果表明,随着切碎长度增加,气味评分和总分总体呈降低趋势,中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)含量呈增加趋势,丁酸含量显著增加;相比乳酸菌发酵组,复合菌剂发酵组整体气味评分和乳酸含量较高,pH值和NDF、ADF含量较低。综上,不同切碎长度和发酵方式对于全株饲用谷子青贮质量均有显著影响。降低切碎长度和使用复合菌剂发酵均有助于促进纤维分解,减少丁酸产量,改善青贮感官评分。     

Detoxification of Aflatoxin-Contaminated Maize by Neutral Electrolyzed Oxidizing Water

Aflatoxins, a group of extremely toxic mycotoxins produced by Aspergillus flavus, A. parasiticus and A. nomius, can occur as natural contaminants of certain agricultural commodities, particularly maize. These toxins have been shown to be hepatotoxic, carcinogenic, mutagenic and cause severe human and animal diseases. The effectiveness of neutral electrolyzed oxidizing water (NEW) on aflatoxin detoxification was investigated in HepG2 cells using several validation methodologies such as the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, the induction of lipid peroxidation, the oxidative damage by means of glutathione modulation, the Ames test and the alkaline Comet assay. Our results showed that, after the aflatoxin-contaminated maize containing 360 ng/g was soaked in NEW (60 mg/L available chlorine, pH 7.01) during 15 min at room temperature, the aflatoxin content did not decrease as confirmed by the immunoaffinity column and ultra performance liquid chromatography methods. Aflatoxin fluorescence strength of detoxified samples was similar to untreated samples. However, aflatoxin-associated cytotoxicity and genotoxicity effects were markedly reduced upon treatment. According to these results, NEW can be effectively used to detoxify aflatoxin-contaminated maize.