A compendium of raw material digestibilities for barramundi,Lates calcarifer

A series of experiments were conducted to examine the nutrient and energy digestibility of a suite of diets and specific test raw materials when fed to juvenile (179 to 439 g) barramundi, Lates calcarifer. Each of the diets was prepared using a twin‐screw extruder to mimic modern aquafeed manufacturing processes. Each of the diets was fed to juvenile barramundi for a minimum of a week to allow acclimation to the diet before the faeces were collected using stripping methods. A broad range of digestible nutrient and energy values among the different raw materials were observed, with protein digestibilities ranging from 36% to 106% and energy digestibilities ranging from 36% to 93%. This range in nutritional values of the different raw materials provides substantial utility in allowing the formulation of diets on a digestible nutrient and energy basis across the Asia Pacific region. These results also provide critical data to help underpin the replacement of both fishmeal and fish oil in barramundi diets.     

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%。     

巴东皱皮木瓜发育及主要成分的变化分析

以湖北巴东产的皱皮木瓜为试验材料,分别在皱皮木瓜果实7个不同生长期采样,通过果实颜色、纵横径、鲜果质量等形态特征的测定,并采用HPLC法对不同生长期内的有效成分(齐墩果酸、熊果酸、原儿荼酸、绿原酸)进行检测,综合评价皱皮木瓜最佳的采收季节和质量指标.结果 表明:(1)皱皮木瓜的纵径、横径、鲜果质量增长随生长阶段呈逐渐递...     

茶叶主要活性成分的保健功能与作用机制研究进展

茶叶中的生物活性物质对人体具有多种保健功效,如调节糖脂代谢、抗氧化、防癌抗癌、增强免疫力等。本文综述了近五年来国内外有关茶叶中几种主要活性成分保健功效及其作用机制的研究进展。     

长双歧杆菌L-DT的高密度培养

针对益生菌株长双歧杆菌L-DT(Bifidobacterium longumssp.longumL-DT)产品线单一,菌株应用需多元化的问题,采用高密度培养技术,利用食品级原料,通过单因素试验、Plackett-Burman试验、最陡爬坡试验和响应面分析优化液态培养基和培养条件。结果表明:适合L-DT生长的培养基中各成分的质量分数为,葡萄糖1.5%、乳糖2.4%、酵母浸粉2.26%、酵母蛋白胨2%、低聚异麦芽糖1.5%、西红柿汁3%;培养条件为,菌液接种量4.46%、初始pH6、温度37℃。培养得到的菌液OD600为1.113,与模型预测值1.104无显著性差异,L-DT活菌值达1.5×109 CFU/mL。在7L发酵罐中进行放大培养验证,L-DT活菌数最高可达5×109 CFU/mL,是试管培养的3.33倍。     

红松不同部位精油的成分分析及抑菌活性

[目的]植物精油是安全并有良好抑菌效果的天然产物,在食品防腐剂领域潜力巨大.本研究通过对红松不同部位精油成分与抑菌活性的研究,能为开发安全绿色的食品防腐剂及为其在食品、化妆品等领域的应用提供理论基础.[方法]采用水蒸气蒸馏法从红松的松针、松塔、松壳中制备精油,采用气相色谱-质谱(GC-MS)联用技术结合保留指数(RI)...     

Evaluation of apparent digestibility coefficients of individual feed ingredients in spotted rose snapper Lutjanus guttatus (Steindachner, 1869)

Apparent digestibility coefficients (ADCs) for dry matter, crude protein, energy and essential amino acids for five commonly used feed ingredients were determined for juvenile spotted rose snapper Lutjanus guttatus (average body weight 90.6 g). ADCs were determined using the stripping technique to collect faeces after fish were fed a reference diet and test diets composed of 700 g kg^?1 reference diet and 300 g kg^?1 test ingredient. Chromic oxide (Cr₂O₃) was used as an inert indicator. Ingredients tested included sardine fishmeal (FM), canola meal (CM), tuna by‐products meal (TBM), poultry by‐product meal pet grade (PBM‐PG) and solvent‐extracted soybean meal (SBM). In general, all ingredients showed high digestibility values for all essential amino acids, although differences were detected among ingredients. ADC values for dry matter, protein and energy ranged 77.0–80.4%, 84.3–82.5% and 89–88.8%, respectively, for marine ingredient and land‐based animal protein sources, and 75.0–74.2%, 81.5–80.9% and 87.4–86.8%, respectively, for the plant‐based protein source. SBM, TBM and PBM‐PG should be further evaluated in feeding trials as partial FM replacements in rose snapper L. guttatus diets. Knowledge of ADC values for these ingredients will allow feed producers to develop nutritionally balanced, low‐cost feed formulations for this species.     

Effect of Toxins Isolated from Exserohilum monoceras (Drechsler) Leonard and Suggs on Echinochloa crus-galli (L.) Beauv.

Exserohilum monoceras (Drechsler) Leonard and Suggs is a potential biocontrol agent for the control of Echinochloa species. This fungus causes leaf blight in Echinochloa species, but does not damage rice. Phytotoxicity of the fungal fermented broth was evaluated through the bioassay and the active ingredients were preliminarily isolated by using silica gel column chromatography (CC) in this study. The most active fraction 5-Ⅲ was obtained and analyzed by gas chromatography-mass spectrometry (GC-MS). The results show that 5-Ⅲ consisted of many compounds, in which 36 compounds accounted for 94.24% of total peak area. Di-n-butyl phthalate (DBP) displayed the highest activity accounted for 9.24% of the total peak area, suggesting that DBP may be one of the main active compounds produced by E. monoceras.     

响应面法优化慕萨莱思配方的研究

本研究向慕萨莱思基酒中加入枸杞、玫瑰花、藿香、杏干四种辅料,测定添加辅料后慕萨莱思中的黄酮含量及感官评价得分,研究单一添加及复合添加对慕萨莱思品质的影响,并通过响应面优化试验确定慕萨莱思的最优配方。结果表明:结合黄酮含量和感官评价,慕萨莱思中黄酮含量均随四种辅料添加量的增加而增加,单因素试验得出杏干10 g/L、枸杞8 g/L、玫瑰4 g/L、藿香0.4 g/L为最佳添加量,对应的慕萨莱思中黄酮含量分别为0.30、0.39、0.36、0.31 g/L。随着四种辅料添加量的增加,感官评分均呈先升高后降低的趋势。利用响应面优化得出最佳辅料添加量为:杏干12 g/L、枸杞10 g/L、玫瑰5 g/L、藿香0.4 g/L,此时慕萨莱思中黄酮含量达到0.80 g/L,产品色泽莹润,澄清度高,果香和酒香和谐,典型性突出,感官评分最高。     

未来饲料新成分——茶渣的应用进展

茶渣含有多种有效成分,其中的营养物质可以代替常规的饲料原料;其他的一些成分可以作为饲料添加剂,使用范围非常广。而且茶渣在我国资源丰富、价格便宜,在饲料中直接使用或者间接添加都能够提高动物的生产性能,目前在饲料中的应用已经被研究,文章综述了茶渣中的有效成分以及在饲料中的应用价值。