Effects of replacing fish meal with rubber seed meal on growth,nutrient utilization,and cholesterol metabolism of tilapia (<Emphasis Type="Italic">Oreochromis niloticus</Emphasis> × <Emphasis Type="Italic">O. aureus</Emphasis>)

A feeding trial was conducted to evaluate the effects of replacing fish meal with rubber seed meal (RSM) on growth, nutrient utilization, and cholesterol metabolism of tilapia (Oreochromis niloticus × Oreochromis aureus). Five experimental diets were formulated with 0, 150, 300, 450, and 600 g kg^?1 RSM replacing graded levels of fish meal, respectively. Each diet was randomly assigned to triplicate groups of 25 fish (initial average weight 65.3 g) per aquarium in a rearing system maintained at 29 ± 1 °C for 8 weeks. Dietary 150 g kg^?1 RSM inclusion did not affect the weight gain and daily growth coefficient, whereas these were depressed by a further inclusion. Additionally, feed efficiency ratio and protein efficiency ratio were not affected by dietary RSM inclusion regardless of inclusion level. However, the inclusion of 450 and 600 g kg^?1 RSM decreased the mid-intestinal trypsin, lipase, and amylase activities; the hepatic acyl-CoA/cholesterol acyl transferase; low-density lipoprotein receptor; and 3-hydroxy-3-methyl-glutaryl-CoA reductase activities. Similarly, dietary 600 g kg^?1 RSM inclusion inhibited the plasma catalase and hepatic glutathione peroxidase activities. These results indicated that 150 g kg^?1 RSM can be included in tilapia diets, whereas higher inclusion of RSM inhibited the growth rate, digestive enzyme activity, antioxidant capacity, and cholesterol metabolism.     

Improvement of ink-jet printing performances using β-cyclodextrin forming inclusion complex on cotton fabric

Cotton fabric was modified with β-cyclodextrin (β-CD) forming inclusion complex to yield color strength, pattern sharpness, and color fastness for ink-jet printing. The modified cotton fabric was confirmed with the presence of new strong absorption peaks around 1713 cm^-1 and 1243 cm^-1 in FT-IR. β-CD had been covalently grafted on cotton fabric via the esterification reaction of citric acid (CTR) with cellulose and β-CD. The results indicated that printing performances of the ink-jet printed fabric were enhanced through β-CD modification. The K/S value was enhanced from 4.21 to 6.72, the width of printed line was decreased from 1.48 mm to 1.25 mm, and the color fastness was improved to 3-4 level. These improvements were due to the truncated cone structure of β-CD, which can form inclusions with water-based pigment. Meanwhile, the crease recovery performance was also improved with the aid of CTR. A comparison between the unmodified and modified cotton fabric suggested that the crease recovery angle of β-CD modified cotton fabric was increased by 25.0 % in the warp direction. Therefore, printing performance and crease recovery performance of β-CD modified and water-based pigment printed cotton fabric were enhanced remarkably.     

Replacement of Fishmeal by a Mixture of Soybean Meal and Chlorella Meal in Practical Diets for Juvenile Crucian Carp,Carassius auratus

A growth trial was conducted to evaluate the effect of a mixture of soybean meal and Chlorella meal (SCM) as a dietary fishmeal (FM) substitute on growth performance, apparent digestibility coefficients (ADCs), digestive enzymatic activities, and histology of juvenile crucian carp, Carassius auratus. Five isonitrogenous and isoenergetic diets were formulated to replace 0 (SCM0), 25 (SCM25), 50 (SCM50), 75 (SCM75), and 100% (SCM100) of protein from FM with SCM, respectively. The diets were fed to triplicate groups of juvenile crucian carp for 6 wk. Weight gain, specific growth rate, feed intake, protein efficiency ratio, and intestinal digestive enzymatic activities (amylase, trypsin, and lipase) tended to decline with increasing FM replacement levels (P > 0.05). Dietary SCM substitution significantly influenced dry matter content in muscle, and crude protein and lipid contents in liver (P < 0.05). ADCs for dry matter, protein, lipid, energy, and most amino acids showed no significant differences between the control and SCM25 group, but tended to decline with replacement levels over 25%. Higher SCM substitution (50–100%) caused karyopyknosis and necrosis in liver, but intestinal histology did not show noticeable pathological changes. The present study indicated that FM could be replaced by 25% of SCM, without significant adverse growth performance, feed utilization, and histology of crucian carp.     

多环芳烃在茶树鲜叶及绿茶加工过程中残留水平研究

利用气相色谱-串联质谱联用仪监测了茶树鲜叶及其绿茶加工中多环芳烃(PAHs)的残留水平。结果表明,不同地区茶树一芽二叶样品PAHs含量差异明显,产地环境PAHs污染程度对茶鲜叶PAHs含量影响较大。茶芽、嫩叶、老叶PAHs含量分别在40.5~52.8μg·kg~(-1)、50.0~67.4μg·kg~(-1)和91.5~97.6μg·kg~(-1)之间,PAHs含量大小顺序为老叶嫩叶芽。汽车尾气对交通公路旁茶树芽和嫩叶PAHs含量影响较大,且对50 m范围内茶树鲜叶影响更明显。电加热干燥模式下,水分散失和PAHs挥发是影响绿茶加工过程中PAHs含量的两个关键因子。加工环节过后,茶叶PAHs含量由61.0μg·kg~(-1)上升到166.1μg·kg~(-1)。摊放和干燥过程中PAHs大量挥发,造成茶叶干重中PAHs残留量由292.0μg·kg~(-1)降低到171.9μg·kg~(-1)。     

Growth performance and whole‐body composition of yellow catfish (Pelteobagrus fulvidraco Richardson) under feeding restriction

Fish growth is an important index in aquaculture practice. However, the effect of growth under restricted feeding on quality of fish grown to the same size remains poorly unknown. In this study, yellow catfish were reared by feeding them at three different feeding rates such as low (FR‐L group), medium (FR‐M group) and high (apparent satiation) ration levels for 82, 58 and 34 days to reach the same size, respectively. After this period, the growth performance, whole‐body amino acid composition and fatty acid profile of the fish were evaluated. Feeding restriction led to significant decreases in specific growth rate and feed conversion efficiency. Significant increases in dry matter, protein and energy contents were observed in fish under both restricted feeding treatments. FR‐L‐treated fish had significantly lower whole‐body essential amino acid contents, and significantly higher Ala and non‐essential amino acid contents compared to fish fed to satiation. Fish in restricted feeding treatments had significantly higher n‐3 PUFA and n‐3/n‐6 ratio compared to the fish fed to satiation. The present results indicate that from a quality perspective, there are certain advantages in improvement of whole‐body composition and enrichment of n‐3 PUFA associated with the restricted feeding of yellow catfish at slow growth rate.     

Influence of dietary lipid on growth performance and some lipogenesis‐related gene expression of tongue sole (Cynoglossus semilaevis) larvae

A 30‐day feeding trial was conducted to investigate the effects of dietary lipid levels on growth performance, activities of digestive enzymes, fatty acid composition and some lipogenesis‐related gene expression of half‐smooth tongue sole (Cynoglossus semilaevis) larvae. Five isoproteic diets were formulated with graded lipid levels (6.68%, 9.84%, 13.47%, 17.89% and 21.88% dry weight) using fish oil as the main lipid source. Each diet was randomly allocated to triplicate groups of 150 larval tongue sole (35 DAH, 54 ± 1 mg). Fish were fed five times daily to apparent satiation during the feeding experiment. Results showed that, the survival rate (SR) of larvae increased significantly firstly, and thereafter decreased significantly. The specific growth rates (SGR) of larvae fed the diet with 13.47% lipid were significantly higher than other treatments. Larvae fed 9.84% or 13.47% dietary lipid showed higher trypsin, lipase, leucine aminopeptidase and alkaline phosphatase (AP) activities than other treatments, whereas amylase activity nearly showed reverse trend with them. The fatty acid composition of the tongue sole larvae was well correlated with dietary fatty acid profile. Expression of acetyl‐CoA carboxylase alpha (ACC1) was found to be slightly negatively correlated with dietary lipid level, and high dietary lipid level depressed the expressions of acetyl‐CoA carboxylase beta (ACC2) and fatty acid synthase (FAS) mRNA expression significantly, implying that larvae may cope with high dietary lipid mainly through down‐regulating lipogenesis‐related gene expression of FAS and ACC2. Besides, on the basis of SGR, the optimal dietary lipid level for larval tongue sole was estimated to be 13.56% using second‐order polynomial curve.     

基于UHPLC-Q-TOF/MS的不同产地普洱生茶化学成分差异研究

为了更加全面地了解产地对普洱生茶品质与化学成分的影响,本研究选取来自临沧市、普洱市、西双版纳州三大产区12个茶山(自然村)的普洱生茶样品,采用超高效液相色谱-四级杆-飞行时间质谱(UHPLC-Q-TOF/MS)对不同产地普洱生茶的非挥发性代谢物表型进行了研究。结果表明:不同产地普洱生茶的化学成分在含量上具有较大差异,且具有明显的产地特征。采用主成分分析,可以对来自西双版纳自治州(包括勐腊县、勐海县、景洪市)、普洱市、临沧市3个地级行政区的普洱生茶进行有效区分,也可以对来自普洱茶产区的东南、西南、西北3个区域的普洱生茶进行有效区分。进一步鉴定了普洱生茶中79种主要成分,并对其在12个茶山(自然村)的普洱生茶中的含量分布,以及与不同产地普洱生茶滋味品质的关系进行了分析。本研究表明,基于UHPLC-Q-TOF/MS的茶叶非挥发性化学成分轮廓可以作为普洱生茶产地判别的依据。     

转基因抗虫棉中棉所76高效制种技术规程

总结了优质抗虫棉中棉所76高效制种技术，包括：制种田的选择、前期准备、亲本种植与管理、制种程序及注意事项等关键技术。     

贝母属植物叶绿体基因组候选SNP位点应用分析

贝母属植物是中国中药材的宝库,由于形态上难以区分,在民间应用、临床应用和中药市场中还存在混淆应用、以次充好的现象,急需开发基于新型分子标记位点的精准检测方法。本研究应用多重序列比对、SNP筛选等生物信息学分析手段,对贝母属15种植物28条叶绿体基因组序列进行分析。结果发现,贝母属叶绿体基因组DNA同源性达97.22%,通过分析共发现SNP位点5879个,其中川贝母类鉴别候选位点71个,川贝母鉴别候选位点4个,瓦布贝母鉴别候选位点37个,太白贝母鉴别候选位点147个,浙贝母鉴别候选位点91个,湖北贝母鉴别候选位点271个,平贝母鉴别候选位点1393个,伊贝母鉴别候选位点89个。本研究还对SNP位点在精准鉴定、精确定量应用方面进行了讨论,可为川贝母中药资源鉴定提供技术支撑。     

麻地膜对设施樱桃番茄(Solanum lycopersivon)生长及产量的影响

为了明确麻地膜覆盖在设施大棚内对樱桃番茄生长及产量的影响,本研究采用‘浙樱粉1号’为实验材料,设置3个处理:麻地膜覆盖、塑料地膜覆盖及对照(不覆盖),比较了不同覆盖措施对‘浙樱粉1号’株高、茎粗、单株鲜重、结果数量及樱桃番茄鲜果重的影响。结果表明,在设施大棚内采用麻地膜覆盖增加了‘浙樱粉1号’株高、茎粗、结果数量及樱桃番茄鲜果重。麻地膜覆盖对设施大棚内种植的樱桃番茄有增产作用,麻地膜的推广应用可以减少塑料地膜对环境污染,利于农业的可持续发展。