连翘叶精油微胶囊制备工艺优化及其对油脂抗氧化的影响

为探索制备连翘叶精油微胶囊的工艺条件及其对油脂的抗氧化效果,以包埋率为评价指标,在单因素试验的基础上,采用响应面法对连翘叶精油微胶囊的工艺条件进行了优化,同时采用测定过氧化值（POV）、脂肪氧化程度值（TBARS）的方法探索了微胶囊对油脂的抗氧化能力。结果表明,连翘叶精油微胶囊的最佳工艺参数为：壁芯比8∶1（g/mL）,包埋温度60 ℃,包埋时间2.3 h,包埋功率400 W,在此条件下连翘叶精油微胶囊包埋率可达44%。油脂抗氧化研究结果表明,微胶囊组ML（0.20 g）、MM（0.10 g）、MS（0.05 g）的POV值高于阳性对照组（VC）,但明显低于空白对照组;微胶囊ML、MM、MS三组的TBARS值低于空白对照组,且随着连翘叶精油微胶囊用量的增大,其对油脂氧化的抑制作用逐渐增强。     

不同浓度硝基苯对水稻发芽和秧苗生长发育的影响

试验结果表明,硝基苯浓度达到27倍(0.34 mg/L)以上对水稻发芽产生明显影响,致使芽率下降.不同浓度的硝基苯对不同品种的发芽率影响不显著.随着浓度的增加,同一品种株高基本呈降低趋势,根数、叶片与对照差异显著.     

不同播期对水稻秧苗素质影响的研究

通过对不同播种期的秧苗素质的研究,确定最佳的播种时期.结果表明:第1叶鞘高与2叶长呈极显著的正相关(r=0.8201**);秧龄期和株高呈极显著正相关(R=0.9367**).结合2006年4月份气温特点,并通过对第1叶鞘高、2叶长、根数、株高等性状分析,初步确认三江地区水稻最佳播种期是4月10～15日.     

促花肥施氮对超级杂交稻冠层叶片生长及光合速率的影响

以超级杂交稻两优培九和国稻6号为材料,研究了促花肥不同施氮量(0,45,90,135,180kg/hm2)对超级杂交稻冠层功能叶片生长和光合速率的影响.结果表明:1)穗分化初期,施氮量对倒1叶(剑叶)和倒2叶的叶片形态影响较大,但对倒3叶生长影响较小.剑叶和倒2叶的长和宽随施氮量的增加而增加,从而增加叶面积,提高上部功能叶的叶面积比率,且对叶长的影响大于叶宽,但叶片过长也易造成开花后叶片的挺直度下降,叶片披散,群体的通风透光性差.2)随着施氮量的增加,叶片的SPAD值相应增加,剑叶的SPAD值在叶片展开后约20d达到最大,随后下降;高氮处理下,倒2叶和倒3叶在开花后期SPAD值下降加剧,衰老加快.3)促花肥增加施氮量能提高水稻剑叶的光合速率.齐穗后剑叶的SPAD值和光合速率呈正相关,功能叶片的光合速率从大到小依次为剑叶、倒2叶、倒3叶.     

竹叶抗氧化物浸泡-乳清分离蛋白涂膜对冷藏富硒虹鳟蛋白质理化性质的影响

为从蛋白质水平解释竹叶抗氧化物浸泡-乳清分离蛋白涂膜对富硒虹鳟的保鲜机理,实验将鲜活富硒虹鳟去除头、内脏和表皮,切块后浸泡在1.0%的竹叶抗氧化物（AOB）溶液中（去离子水作为对照）,再进行乳清分离蛋白（WPI）溶液涂膜,25℃下鼓风吹干表面水分后置于4℃冰箱中贮藏1、4、7、10和13 d。测定鱼肉中肌原纤维蛋白和TCA-可溶性肽的含量、蛋白质的分子内价键,以及肌原纤维蛋白的总巯基含量、表面疏水性和二级结构,分析涂膜对冷藏富硒虹鳟蛋白质理化性质的影响。结果显示,冷藏期间,WPI组的肌原纤维蛋白含量和二级结构中β-折叠的含量显著高于对照组。冷藏1～7 d,WPI组的TCA-可溶性肽和二硫键含量以及表面疏水性指数（H₀）显著低于对照组,总巯基含量呈相反趋势,但随着冷藏时间的延长这些差异逐渐减弱。冷藏13 d时,WPI组与对照组无显著差异。3个实验组中,1.0%AOB+WPI组的肌原纤维蛋白、总巯基、氢键、二级结构中α-螺旋和β-折叠的含量在冷藏期间最高,H₀、TCA-可溶性肽、二硫键和二级结构中β-转角含量最低。WPI在鱼块表面形成一层薄膜,可...     

Investigations on the digestibility and metabolizability of the major nutrients and energy of maize leaves and barnyard grass in grass carp (Ctenopharyngodon idella)

In the uplands of northern Vietnam, culture of grass carp contributes significantly to income and household food security of Black Thai farmers. Maize is one of the most important upland crops and barnyard grass is the most important weed in the paddy rice fields. Thus, these are frequently used by small‐scale fish farmers as fish feed. An 8‐week feeding trial was conducted simultaneously in a recirculation and in a respirometric system to determine the digestibility and metabolizability of the nutrients of maize leaves and barnyard grass, to assess their crude protein, lipid and energy conversion and to estimate the energy allocation in grass carp. The following diets were used: diet ‘A’ (reference diet) containing 39% crude protein with 19.8 MJ kg^?1 gross energy; diets ‘B’, ‘C’ and ‘D’, which contained the same amount of the reference diet as the control diet, supplemented with a known amount of dried barnyard grass, dried maize leaves or fresh maize leaves, respectively. Five fish were assigned to each treatment in each experimental unit. Reference and test diets were fed to fish and faecal samples were collected and the oxygen consumption was measured in order to set up an energy budget of the fish over the whole experimental period. The weekly development of the body weight was recorded. The body weight gain of the fish fed diet D was significantly higher than that of the group fed diet A, which also in turn was significantly higher than that of fish fed diet B or C. The apparent digestibility coefficients (ADC) of nutrients and gross energy for the different experimental diets in fish kept in the aquaria were, for diets A, B, C and D respectively, 94.1%, 60.9%, 70.5% and 84.7% for protein, 91.3%, 60.7%, 76.8% and 71.8% for lipid; 95.9%, 44.5%, 60.6% and 69.1% for gross energy. The partial ADC of plant leaf ingredients were determined and barnyard grass and dried maize leaves were found to be not only poorly digestible but having negative impact on the digestibility of the reference diet, while fresh maize leaves were well digested. The results of the present study indicated that fresh maize leaves have a good potential to be used as supplement in diets for grass carp.     

印度Leh地区沙棘叶中脂肪酸的含量

本文用气相色谱仪分析了印度Leh地区沙棘叶油中种脂肪酸的含量,结果显示：该地区沙棘叶油中富含硬脂酸,其值可以达到13．853％,山嵛酸13．938％,亚油酸7．579％,掬焦油酸6．638％,十八稀酸4．622％。     

杀青方式对机采绿茶理化品质的影响

为了提高茶树机采绿茶杀青品质,以机采鲜叶为原料,比较微波、汽热、电热滚筒和电磁滚筒耦合热风4种杀青方式所制机采绿茶的感官品质、茶叶内含成分、色泽和香气。结果显示：电磁滚筒耦合热风杀青所制绿茶的感官得分（89分）最高,所制干茶的色相值（a/b）相对更绿（p<0.01）,酚氨比较低（p<0.05）,非酯型儿茶素、酯型儿茶素和儿茶素总量也相对较低（p<0.01）;电磁滚筒杀青所制绿茶的栗香型成分含量较高,如藏红花醛、癸醛、β-环柠檬醛、庚醛和3,7-二甲基-2,6-二辛烯醛等高级醛类,香叶基丙酮、β-紫罗酮和1-戊烯-3-酮,反式-2-辛烯醇、芳樟醇、反式-橙花叔醇等,以及二甲硫、2-甲基呋喃和1-乙基吡咯等杂环化合物,说明电磁滚筒耦合热风杀青集成了不同工艺特点,所制机采绿茶滋味鲜爽,栗香明显,该工艺有利于提高机采绿茶品质,对实际生产具有指导作用。     

从一本六年产量收入日记帐分析茶叶增产增收途径

2012年,我们在实施全国农业示范推广补助项目,对湖北省宜昌市夷陵区茶叶科技示范户周先明进行调查,发现该户从2009年起每天采茶都记了日记帐,我们分析了他4年采茶产量收入,春茶产量占全年29%,其收入占全年60%,亩产鲜叶量为1256.3公斤,亩现金收入为6054元。2013年实施该项目后,我们一是通过他多年每日记载数据分析绘制成图;二是实地茶园土壤肥力性状,树体结构和管理措施调查分析,提出其水田茶园不同于过去旱坡茶园的综合高效管理增产增收途径,在2013-2014年早春干旱情况下,茶叶产量收入得到较大提高,对全区茶叶生产具有重要指导作用。     

初烤烟叶专业化分级效率研究

设计4种工位的流程化分级方式,分别对第2、第4、第6炕次烟叶实施专业分级试验,研究不同的流程化分级方式对烟叶分级速度与质量的影响。结果表明:二工位和三工位流程化分级速度最快,分别为60.75、60.51kg/(人.工),较一工位分级分别多6.82、6.58 kg/(人.工),较四工位分级分别多9.38、9.14 kg/(人.工);四工位、三工位流程化分级时各炕次烟叶分级质量最好,烟叶等级合格率分别为91.78%、90.38%,比一工位分组分别高24.23及22.83百分点,比二工位分级分别高14.55及13.15百分点。对比4种不同方式的烟叶分级速度及分级质量,以三工位流程化分级效率最高。