集约化种植砖红壤养分变化分析

调查分析位于广东省湛江农垦属下华海公司、南华农场、红星农场、丰收公司、广前公司、五一农场、湖光农场和友好农场等8个单位1 918个土样的养分状况,与第二次土壤普查比较,对比集约化种植后砖红壤肥力变化。结果发现：pH呈下降趋势,即有土壤酸化特征;土壤有机质含量总体呈现较高水平,但也呈现下降趋势;土壤全氮总体仍处于中等偏上水平;土壤有效磷含量明显提高,总体处于良好水平;土壤速效钾含量有很大程度增加,但仍处于中等水平。     

茶多酚对淀粉酯纳米颗粒及其稳定的Pickering乳液性质的影响

为探究茶多酚（Tea Polyphenols, TPs）对辛烯基琥珀酸酐（Octenyl Succinic Anhydride, OSA）酯化淀粉纳米颗粒（Starch Nanoparticles,SNPs）及其稳定的Pickering乳液性质的影响,该研究在制备OSA-SNPs的过程中添加TPs,研究TPs对OSA-SNPs的理化性质和乳化性能的影响。结果发现,添加TPs使OSA-SNPs的平均粒径增加、表面Zeta电位绝对值下降、接触角减小（P<0.05）。通过傅立叶红外光谱扫描发现,TPs与OSA-SNPs之间存在氢键和疏水相互作用。在TP-OSA-SNPs稳定的乳液中,增加TP-OSA-SNPs的质量浓度（从0.5 g/mL至2.0 g/mL）,乳滴平均直径明显减小（P<0.05）;当TP-OSA-SNPs的质量浓度增加至2 g/mL时,乳液形成了油滴紧密堆积的界面结构,能够抑制油滴迁移。通过加速氧化试验发现,与OSA-SNPs相比,TP-OSA-SNPs稳定的乳液中氢过氧化物值（Peroxide Value, POV）相对较低（P<0.05）,说明TP-OSA-SNPs具有延缓乳液中油脂氧化的作用。结果表明,这种新型具有抗氧化功能的食品级颗粒乳化剂,对构筑淀粉基Pickering乳液载体具有潜在价值。     

西红花抗肿瘤作用的研究进展

癌症明显影响人类的平均寿命和生活质量,而从蔬菜、草药和香料中提取的天然物质可能有助于预防或治疗多种癌症。西红花具有多种活性成分,具有明显的抗肿瘤潜力,民间中医已将其广泛用于治疗很多疾病。该文通过查阅知网、PubMed和SciFinder中相关文献和资料,获得西红花试验数据,并进行归纳总结,着重介绍了西红花及其主要成分,并对国内外大量的体内、体外试验的研究进展进行综述,发现藏红花具有清除自由基和抗肿瘤活性,并在体外和体内模型中均具有明显的抗肿瘤作用。基于当前数据表明,西红花可被视为有潜力的候选临床抗癌药物。     

不同基因型烤烟油分表征化学物质和常规化学成分含量差异比较

[目的]比较不同基因型特色烤烟品种的烟叶油分表征化学物质和常规化学成分含量的差异.[方法]基于对不同基因型烤烟烟叶油分表征化学物质和常规化学成分差异的探索,以毕纳1号、云烟87、K326和南江3号4个烤烟品种为研究对象,分析了不同基因型烤烟烟叶油分表征物质和常规化学成分含量的差异.[结果]试验表明,云烟87和南江3号的烟叶油分表征化学物质总体好于K326和毕纳1号,云烟87、毕纳1号、K326和南江3号烟叶含钾量均偏低,云烟87、毕纳1号和K326的上部叶烟碱含量高,南江3号和云烟87的中、上部叶还原糖和总糖含量相对较高.[结论]研究可为烟叶质量偏低、油分差的烟区选育和推广优良烤烟品种提供技术支撑.     

乳品主要成分及添加剂对格氏乳球菌素LG34抑菌活性的影响

为了探讨新型广谱乳酸菌细菌素格氏乳球菌素LG34在乳品中的应用效果,研究乳品主要成分及乳品添加剂对格氏乳球菌素LG34抑菌活性的影响。采用琼脂扩散法,以格氏乳球菌素LG34为空白对照组,以添加乳品主要成分及添加剂的格氏乳球菌素LG34为实验组。结果表明:乳品主要成分乳糖、干酪素、乳脂肪显著降低了格氏乳球菌素LG34的抑菌活性;乳品添加剂六偏磷酸钠显著降低了格氏乳球菌素LG34的抑菌活性,羧甲基纤维素钠显著提高了格氏乳球菌素LG34的抑菌活性。     

不同光质对黄芪生长及药用成分积累的影响

为探讨适合黄芪(Astragalus membranaeus(Fisch.)Bge)生长及药用成分合成积累的光照条件,提高黄芪药材的产量与质量,运用植物逆境生理和次生代谢研究理论,研究了蓝光、黄光、红光、白光和自然光(对照)条件下,黄芪3种主要药用成分含量的动态变化。结果表明,蓝光和黄光可以促进黄芪根部干物质的积累,并可以有效提高药用成分含量,而红光则不利于黄芪干物质的积累;蓝光下黄芪黄酮的含量最高,比自然光下提高了51%,经济产量提高了56%;黄芪多糖和皂甙无论是含量还是经济产量都是在蓝光下最为理想,其中,黄芪多糖的含量比自然光提高了23.9%,经济产量提高了19.3%,黄芪皂甙的含量比自然光提高了106%,经济产量提高了105%。     

烟草与罗勒科间远缘杂交育种的研究

利用烟草与药用植物罗勒进行科间远缘杂交,以期培育出含医药成分的新型烟草,以缓解吸烟与健康的矛盾。采用无性与有性杂交相结合的方法,克服其杂交不孕问题。经酶谱测定,杂种稳定品系含有亲本药用植物的遗传物质;镜检(F1~F18)细胞染色体呈杂合状态;经医药成分鉴定均含有药用植物亲本中相应的医药成分,并产生了新的医药成分;烟叶评吸具有药物香气。化学成分测定结果表明,罗勒烟具有低糖,中、高烟碱含量的特点。经卷烟企业验证其可用性,具有较高的应用价值。     

Apparent digestibility coefficients of nutrients in brewer's and rendered animal by-products for rainbow trout (Oncorhynchus mykiss (Walbaum))

Two experiments were conducted to measure the apparent digestibility coefficients (ADCs) of nutrients, dry matter, and energy in by‐products of the brewing industry and in selected animal protein ingredients for rainbow trout. In experiment 1, 500 rainbow trout (average body weight 170.8±5.5 g) were stocked in ten 140‐L digestibility tanks with 50 fish per tank and two tanks per diet. Yttrium oxide was used as an inert marker in the diets. The high fibre content of brewer's dried grains (BDG) affected the ADCs of dry matter but not of protein or amino acids. Brewer's dried yeast had a higher protein content than BDG, but ADC values for protein and amino acids were significantly lower. The ADCs of phosphorus were similar among brewer's dried products. The BDG high‐protein, fraction had marginally higher ADC values for dry matter, protein and amino acids than regular BDG. Conditions in experiment 2 were similar to those in experiment 1. ADC values for spray‐dried porcine plasma were over 98% for dry matter, crude protein, crude fat, and gross energy. ADC values for spent hen meal were higher than those of poultry by‐product meal or feather meal, with the exception of gross energy. However, spent hen meal was unpalatable. The ADCs in these ingredients were variable, and this variability must be taken into account when these ingredients are formulated into feeds for fish.     

Reassessment of phosphorus and nitrogen discharge from commercial carp feeds

ABSTRACT:   The present study, one in a series to clarify the phosphorus (P) and nitrogen (N) loading from carp culture, evaluated four commercial diets. The total and available P in these diets varied from 1.57 to 1.86% and from 0.38 to 0.87%, respectively. The control diet, selected based on an earlier experiment, contained 1.40% total P and 0.68% available P. The 7-week feeding trial was performed with juvenile carp. Superior feed gain ratio was obtained for the control diet (1.00) and it varied from 1.19 to 1.56 among the commercial diet groups. Similarly, the control diet showed higher rates of P absorption (43.8%) and retention (33.1%) than the rest (absorption: 18.1–40.9%; retention: 10.7–18.7%). Total P loading (kg/t production) was 10.0 for the control group but ranged from 19.1 to 25.0 among the commercial diet groups. Nitrogen absorption was not markedly different; however, fluctuations in retention resulted in N loading (kg/t production) that ranged between 47.1 and 66.3 among the commercial diets, higher than the 34.8 obtained for the control diet. The available P in the commercial diets rarely matched the requirement level, thereby negatively affecting the waste loading. The superior performance of the control diet underscores the fact that effective formulations help in keeping emission levels low.     

漂烫处理和速冻处理对白芦笋营养成分的影响

研究了不同漂烫条件和速冻处理对芦笋过氧化物酶(POD)活性及营养成分的影响。结果表明:漂烫处理和速冻处理造成一定量的蛋白质和氨基酸的损失。95℃条件下,漂烫2.5 min能显著抑制POD活性,较好地保存芦笋的外观品质,较长时间保持速冻芦笋的营养成分。