灌喂必需氨基酸模式溶液对草鱼全鱼_省略_肌肉_肝胰脏蛋白质合成代谢的影响

采用大剂量食道灌喂DL－[4-^3H]-Phe，研究不同EAA模式下，20－30g体重草鱼种的全鱼和肌肉，肝胰脏的蛋白质合成代谢，结果表明：（1）分别缺乏Lys,Met,Trp Arg的4种极端不平衡EAA模式，同草鱼肌肉EAA模式即相对平衡的基础模式相比，肌肉，肝胰脏及全鱼的蛋白质合成速率（FSR）均显著降低，其降低程度高低依次为Met,Lys,Arg,Trp;(2)肝胰脏，肌肉人的蛋白质合成代谢与整体蛋白质合成代谢对EAA模式的改变产生相同的变化趋势，并且三者蛋白质合成代谢速率为肝胰脏＞全鱼＞肌肉；（3）EAA模式的Lys,Met,Trp,Arg4因素中，对肌肉，肝胰脏蛋白质合成速率影响最大的是Met,其余依次为Lys,Arg,Trp。     

The effect of culture on morphology, lipid and fatty acid composition, and polyunsaturated fatty acid metabolism of rainbow trout (Oncorhynchus mykiss) skin cells

Rainbow trout (Oncorhynchus mykiss) skin cell cultures were obtained by trypsinization of the tissue and grown in Leibovitz L-15 medium. Lipid class compositions, and fatty acid profiles of total lipids and individual phospholipid classes were determined at different times of culture. The metabolism of polyunsaturated fatty acids (PUFA) was investigated by incubating primary cultures after 7 and 14 days with [1-¹⁴C]18:2n-6 and [1-¹⁴C-]18:3n-3. The change in morphology between epithelial-like primary cultures and fibroblastic-like secondary subcultures was accompanied by alterations in the lipid composition. Polar lipids became predominant by 14 days in culture. The relative proportions of phosphatidylcholine (PC), the most abundant phospholipid, phosphatidylinositol and cholesterol increased significantly, while sphingomyelin decreased. Saturated fatty acids, 18:1n-9, n-6 and n-9PUFA were more abundant in total lipid in cultures at 14 days and 4 months than in cells initially isolated which contained higher percentages of longer chain monoenes and n-3PUFA. The changes in fatty acid composition with time in culture were observed in all the major phospholipid classes. Rainbow trout skin cells in culture desaturated and elongated both 18:2n-6 and 18:3n-3, with 20:4n-6 and 20:5n-3 being the most abundant products, respectively. PC presented the highest incorporation of radioactivity, especially following incubation with 18:3n-3. Lipid metabolism in general increased with the age of primary cultures, with both the amount of C18 PUFA incorporated and metabolized by desaturation/elongation significantly increased in 14 day cultures compared to 7 day cultures. Product/precursor ratios calculated for both n-6 and n-3 fatty acids showed that, while 6 desaturase activity was increased significantly with cell age, 5 desaturase activity was more affected by the fatty acid series, with 18:3n-3 being more readily transformed to 20:5n-3 than 18:2n-6 to 20:4n-6. Further desaturation of 20:5n-3 to hexaenes was low. Overall, the data suggested that the trout skin cell cultures were more similar to mammalian skin fibroblasts than mammalian epidermal/keratinocyte cultures.     

芋田斜纹夜蛾重发原因及防控措施

分析了近年来清流县芋田斜纹夜蛾重发原因,并针对其发生与危害特点,提出加强测报工作、开展农业防治、诱杀防治及化学防治等治理防控措施,以供参考。     

超临界CO2萃取琉璃苣芳香油参数的优化

采用超临界CO2萃取技术,利用正交设计对琉璃苣(Borago officinlis)芳香油萃取参数进行了优化研究.结果表明,影响超临界CO2萃取量最重要因子为萃取压力,其次是萃取温度;最佳萃取工艺参数组合为萃取压力20 MPa、萃取温度35℃、萃取时间2.0 h、CO2流量3.0 L/h.采用该参数组合进行超临界CO2萃取,琉璃苣芳香油含量高达0.684％.     

落花生茎叶中挥发性成分及芳樟醇含量的GC-MS法测定

为了建立气相色谱法测定落花生(Arachis hypogaea L.)茎叶中挥发性成分及芳樟醇含量的方法,通过气相色谱-质谱联用,以石油醚为介质,分析了落花生茎叶中挥发性成分,并测定了落花生茎叶挥发油中芳樟醇的含量。结果鉴定出33种落花生茎叶挥发性成分,其中主要组分为3,7-二甲基-1,6-辛二烯-3-醇(芳樟醇,16.82%)、N-棕榈酸(17.07%)和1-辛烯-3-醇(芳樟醇的分解产物,8.82%),均能与内标物很好地分离。芳樟醇在6.25~200.00μg/m L内线性关系良好(R2=0.999 7)。石油醚中的芳樟醇浓度为10.415 mg/m L,落花生茎叶中芳樟醇浓度为578.611 mg/kg。试验结果表明,该方法适用于落花生茎叶挥发性成分及芳樟醇的测定。     

3种化学类型樟树的生长与精油含量相关分析

以江西省林业科学院樟树基因库中油樟、脑樟、异樟3种化学类型的5年生植株为材料,研究了3种化学类型樟树的精油含量与其生长性状、各部位生物量之间的线性相关关系.结果表明,3种化学类型各部位精油含量与生长性状的相关性比较复杂:油樟叶片、树干和侧根的精油含量与地径呈显著正相关,脑樟各部位精油含量与生长性状相关性不显著,异樟新枝、老枝和侧根的精油含量与树高、地径显著或极显著正相关.3种化学类型各部位精油含量与生物量之间也存在复杂的相关关系:油樟6个部位精油含量与叶片、新枝、老枝的生物量显著相关,脑樟6个部位精油含量与生物量相关均不显著,而异樟新枝、老枝、主根和侧根4个部位的精油含量与生物量显著相关.研究结果可为3种化学类型樟树资源的高效栽培利用提供帮助.     

舒城县油茶低产林形成的原因及改造技术

从品种混杂、管理粗放、林分老化、资金投入不足等方面分析了舒城县油茶低产林的原因,并提出了低产林改造技术,以促进该县油茶产业的发展。     

The essential fatty acid requirement of milkfish (Chanos chanos Forsskal)

The essential fatty acid (EFA) requirement of milkfish was examined by a 12-week feeding trial using defined, purified diets at water temperature of 28–29°C and salinity of 32. The test diets contained varying levels of 18:0 (triglyceride form, TG), 18:3(n–3), 18:2(n–6) and (n–3) highly unsaturated fatty acids (n–3 HUFA). Milkfish juveniles were starved for 7 days and were than fed lipid-free diet for 30 days before the initiation of feeding trials. Low growth and feed efficiency together with high mortalities were observed in fish fed the lipid-free diet as well as in the EFA-deficient diet. Supplementation of 2% 18:2(n–6) to the tristearin based diet did not improve growth rate of milkfish as effectively as feeding with (n–3) fatty acids. The highest weight gain was obtained in milkfish fed a combination of 5% 18:0 + 1.0% 18:3(n–3) + 0.5% 20:5(n–3) + 0.5% 22:6(n–3) although the supplementation of 2% 18:3(n–3) alone or combination of 0.5% 20:5(n–3) + 0.5% 22:6(n–3) to the tristearin based diets were also effective for improvement of growth. Thus, (n–3) fatty acids, such as 18:3(n–3) and (n–3)HUFA were nutritionally more important than 18:2(n–6) for milkfish. The fatty acid composition of the polar lipids from whole body of milkfish juveniles fed the various test diets were influenced by the composition of the dietary fatty acids.     

长叶榧叶部油挥发性成分的色谱/质谱分析研究

采用气相色谱/质谱(GC-MS)联用法测定了长叶榧叶部精油的挥发性成分,初步发现其主要成分是柠檬烯、反式α-蒎烯、β-蒎烯、顺式α-蒎烯、3-莰烯、6,6-二甲基-2-亚甲基-环庚烷、β-月桂烯,其含量分别为32.2%、12.5%、7.1%、6.6%、6.6%、5.5%、4.4%.     

肥料三要素与日本落叶松苗木生理的关系

对肥料三要素与日本落叶松苗木生理的关系进行了研究，结果表明，叶绿素含量与氮、磷肥关系密切（rN=0.91^**,rp=0.61^**)；混施三要素比单施氮肥能提高苗木根系吸收能力；并且三要素混施比单施氮肥提高苗茎纤维素含量，平均提高10．7％。生产上适宜三要素施肥比例为N：P2O5：K2O＝1：0．6：0．4。