纳米Cs_2O/γ-Al_2O_3固体碱催化红麻籽油制备生物柴油

以纳米γ-Al2O3粉体为载体,应用等体积浸渍CH3COOCs制备Cs2O/γ-Al2O3催化剂,并通过TPD-CO2、XRD、TEM等手段对催化剂的碱性、结构和表面形貌进行表征,并将其用于催化红麻籽油制生物柴油反应.通过催化剂活性评价结果,分析了纳米固体超强碱制备过程及酯交换反应过程中各种因素的影响.结果表明,催化剂的粒径为10-25 nm,负载量为2mmol.g-1时,催化剂具有强碱性,其活性最好.甲醇与红麻籽油的摩尔比为9∶1,催化剂用量为油料的2.5%,反应时间3 h,转化率可达到90.7%.     

亚麻籽胶对面团流变性质的影响及其在面条加工中的应用

该文重点研究了添加亚麻籽胶对面粉的粉质特性、面团的流变性质以及面条品质的影响。粉质特性的结果表明,添加亚麻籽胶使面团的吸水率增加,面团的形成时间和稳定时间延长,弱化度降低,使面团的稳定性更好。动态流变性质和超微结构的显微观察表明,添加亚麻籽胶后,亚麻籽胶的网络结构加固了面筋蛋白的网络结构,因而面团的稳定时间和粘弹性均能提高。质构分析的结果表明,添加亚麻籽胶使面条烹煮后的硬度和咀嚼度提高,并具有较好的弹性和拉伸性能,面条的烹煮损失和面汤浊度降低,因而亚麻籽胶可用于面制品中以改善其食用品质。     

亚麻籽在动物生产中的应用现状

随着亚麻籽在食品工业和动物体内的广泛应用,人们对亚麻籽的研究已经成为热点。本文对亚麻籽营养成分、饲用方式及目前在动物生产中的应用现状进行综述,为未来我国进行此方面的研究提供理论基础。     

Effects of extruded flaxseed on layer performance,nutrient retention and yolk fatty acid composition

1. This study was conducted to determine the effects of feeding an extruded flaxseed (EF) on layer performance, apparent total tract nutrient retention (ATTR) and egg yolk fatty acid concentrations.

2. Seventy-two White Leghorn laying hens (58-week-old; three per cage) were randomly allotted to one of four dietary treatments: 0%, 7.5%, 15.0% and 22.5% of EF-supplemented diets for 8 weeks.

3. Supplementation with EF had no effect on feed intake, egg production, feed conversion ratio and egg weight. Egg components (yolk, albumen and shell percentages) were similar among treatments, except that shell percentage was greater for layers fed 22.5% EF than those fed 7.5% and 15% EF. The ATTR of dry matter and organic matter were highest for 0% and 7.5% EF, intermediate for 15% EF and lowest for 22.5% EF. Similar reductions on ATTR of crude protein and nitrogen-corrected apparent metabolisable energy were observed for layers fed 22.5% EF relative to those fed 0% or 7.5% EF.

4. Feeding EF at 7.5%, 15.0% and 22.5% of the diet markedly increased (by 92%, 198% and 271%, respectively) egg yolk concentrations of n-3 polyunsaturated fatty acid (PUFA) and reduced saturated fatty acid and n-6 PUFA concentrations.

5. It was concluded that omega-3 labelled eggs (300 mg/60 g of egg) may be produced with low (7.5% of diet) levels of dietary EF without compromising egg production parameters. However, feeding moderate to high levels of EF (i.e. 15% and 22.5% EF) may reduce total tract nutrient and energy utilisation.     

Isolation and antifungal activity of lignans from Myristica fragrans against various plant pathogenic fungi

BACKGROUND: In a search for plant extracts with potent in vivo antifungal activity against various plant diseases, we found that treatment with a methanol extract of Myristica fragrans Houttyn (nutmeg) seeds reduced the development of various plant diseases. The objectives of the present study were to isolate and determine antifungal substances from My. fragrans and to evaluate their antifungal activities. RESULTS: Three antifungal lignans were isolated from the methanol extract of My. fragrans seeds and identified as erythro-austrobailignan-6 (EA6), meso-dihydroguaiaretic acid (MDA) and nectandrin-B (NB). In vitro antimicrobial activity of the three lignans varied according to compound and target species. Alternaria alternata, Colletotrichum coccodes, C. gloeosporioides, Magnaporthe grisea, Agrobacterium tumefaciens, Acidovorax konjaci and Burkholderia glumae were relatively sensitive to the three lignans. In vivo, all three compounds effectively suppressed the development of rice blast and wheat leaf rust. In addition, EA6 and NB were highly active against the development of barley powdery mildew and tomato late blight, respectively. Both MDA and NB also moderately inhibited the development of rice sheath blight. CONCLUSION: This is the first study to demonstrate the in vitro and in vivo antifungal activities of the three lignans from My. fragrans against plant pathogenic fungi.     

亚麻种子及麻屑的综合利用

亚麻是我国西北及华北地区主要的油用经济作物，也是东北地区及云南、新疆的主要纤维用经济作物。亚麻种子的综合利用可带来很高的经济价值。综合利用亚麻种子、亚麻根、亚麻茎可生产多种工业化产品；如可降血脂的亚麻油胶丸、高发泡性食品用亚麻胶、高蛋白饲料、植物雌激素-木酚素、膳食纤维素、建筑复合材料等。进行亚麻种子高技术水平的研究，对亚麻种子进行综合利用将对人类健康起到更大的作用。     

五味子属药用植物木脂素的研究现状与展望

木脂素是五味子属药用植物的主要生物活性成分,其成分、含量与植物器官、部位、产地、生长季节、提取工艺及测定方法等有很大关系,本文中就其研究现状及展望进行探讨,为五味子属药用植物的木脂素类化合物开发利用及质量标准的制定提供参考。     

亚麻籽木脂素对雄性大鼠肌肉生长的促进作用及机制探讨

 【目的】以大豆黄酮为对照,研究亚麻籽木脂素对雄性大鼠骨骼肌生长的影响并探讨其作用机制。【方法】在SD雄性大鼠基础日粮中分别添加大豆黄酮（5 mg?kg-1）和亚麻籽木脂素（50 mg?kg -1）,利用高压液相色谱、放射免疫分析、RT-PCR等方法,分析大鼠血清中亚麻籽木脂素及两种主要代谢产物（肠内酯、肠二醇）浓度、睾酮及生长激素含量、比目鱼肌和下丘脑中ERβmRNA的相对表达量。【结果】亚麻籽木脂素与大豆黄酮均能显著提高雄性大鼠饲料利用率,促进大腿肌肉增重,提高腿肌中RNA/DNA的比值,促进下丘脑和比目鱼肌中ERβ mRNA表达量显著上升,使大鼠血清中睾酮含量增加,极显著性降低血清中尿素氮含量。【结论】亚麻籽木脂素可能通过与ERβ结合,作用于下丘脑-垂体-性腺轴,调节大鼠血清中睾酮水平,抑制蛋白质分解,促进骨骼肌卫星细胞与肌细胞的融合,从而促进骨骼肌生长。     

亚麻籽木脂素在山羊瘤胃中的转化及其对瘤胃代谢的影响

选用6只(4♂、2♀)装有永久性瘤胃瘘管及临时性颈静脉插管的淮南山羊,进行交叉试验.试验期按体重灌胃50 mg·kg-1质量分数为20%亚麻籽木脂素提取物,分别用高效液相色谱法测定木脂素和挥发性脂肪酸含量,研究亚麻籽木脂素在山羊瘤胃中的转化及其对瘤胃代谢的影响.结果表明,在对照期瘤胃液中存在较低质量浓度的亚麻籽木脂素(0.003 mg·mL-1)、肠内酯(0.007 mg·mL-1)及肠二醇(0.017 mg·mL-1),但血清中未检测出木脂素成分.灌胃木脂素提取物能显著提高瘤胃液及血清中上述3种动、植物木脂素含量;同时,木脂素化合物使总脱氢酶活性升高25.5%(P>0.05),并使瘤胃液pH值和氨氮含量分别降低1.1%(P<0.05)和36.3%(P<0.01),微生物蛋白及总挥发性脂肪酸含量分别升高70.1%(P<0.01)和37.4%(P<0.01).结论:在饲喂青干草及豆粕型精料日粮条件下,瘤胃液中存在植物木脂素和2种最主要的动物木脂素.灌胃亚麻籽木脂素提取物后能显著提高3种木脂素含量,且均能被吸收进入血液.木脂素可以直接或间接影响瘤胃内微生物活性,从而改善瘤胃代谢水平.