Effects of natural feeding stimulants and glutamic acid supplementation on the feed intake,growth performance and digestive enzyme activities of red sea bream (Pagrus major) fed fish meal‐free soy protein concentrate (SPC)‐based diet

Two experiments were conducted for red sea bream (Pagrus major). In experiment 1, the optimum level of glutamic acid and natural feeding stimulants to enhance feed intake were determined and found that glutamic acid level of 0.5% and fish meat hydrolysate (FMH) were effective. In experiment 2, fish were fed with soy protein concentrate (SPC)‐based diet with synthetic feeding stimulants (Basal diet), the Basal diet with FMH (FMH diet), the FMH diet with glutamic acid (FMHG diet) and with fish meal diet (FM diet) as a control until satiation for 8 weeks. Feed intake of FMHG‐fed fish was significantly higher than others (p < 0.05). Specific growth rate and the feed conversion ratio of FMHG were comparable to those of FM‐fed fish (p > 0.05). Relative visceral fat ratio and crude lipid content of any SPC‐based diet‐fed fish tended to be lower than those of FM diet‐fed fish. There were no significant differences in trypsin and lipase activities hepatopancreas among treatments. SPC can be utilized as a sole protein source in a diet for red sea bream. The lower growth performance in SPC‐based diet‐ fed fish was not due to poor digestive enzyme secretion but could be associated with lipid utilization disorder.     

滁河水环境污染防治对策研究

滁河为长江下游左岸一级支流,流经安徽滁州及南京江北地区。滁河既是苏皖两省的交界,又是滁州、南京六合区和浦口区的母亲河。但与此同时,滁河也承担了流域内工业废水、农业废水和生活污水等废水的受纳水体功能。滁河的水环境质量直接影响到滁河流域人民的生活饮用水安全。因此,本研究对滁河进行了水环境质量监测,分析了造成滁河水体污染的主要污染源,并调查了产生过量污染的主要原因,在此基础上提出了针对性的水污染防治对策。     

豫南茶树种质资源籽实脂肪含量及脂肪酸组成分析

以豫南地区42份茶树种质资源的茶籽为研究对象,分析了茶籽含仁率及茶籽仁的脂肪含量,范围分别在33.53%~71.60%、17.77%~38.39%。利用气-质联用技术（GC-MS）检测了茶籽仁中的脂肪酸组成和含量,共检测到21种脂肪酸,其中主要成分棕榈酸、硬脂酸、顺-油酸、亚油酸和α-亚麻酸的含量分别在2.64%~5.70%、0.21%~1.11%、7.33%~17.29%、0.09%~8.44%和0.01%~0.15%;相关性分析显示,顺-油酸与十三碳酸、十四碳酸和顺-二十碳二烯酸的含量呈极显著负相关,亚油酸与反-油酸、顺-二十二碳六烯酸含量呈极显著负相关;除了水仙7202茶籽仁中的饱和脂肪酸、单不饱和脂肪酸和多不饱和脂肪酸含量比值为3.08∶12.16∶1,其余茶树种质资源茶籽仁中,这三类脂肪酸的比值均约为1∶2.69∶1.37。中黄1号、农抗早、迎霜、鄂茶11号、龙井43、中选8号、崂山3号和黄金叶8个茶树品种,不仅含仁率和脂肪含量较高,而且茶籽仁脂肪酸的组分和含量丰富、均衡,可初步筛选出来作为豫南地区叶籽两用茶园的候选品种。     

甘蓝型油菜MYB28转录因子对根肿菌和水杨酸的响应特征

MYB转录因子参与植物的生长发育和逆境胁迫过程，在植物防御相关信号反应中起着重要的调控作用。 为了明确MYB28在油菜与根肿菌互作中的作用，对感病甘蓝型油菜中双11中MYB28家族基因在根肿菌接种以及 水杨酸处理后的表达模式进行了分析。不同组织表达模式分析显示，相比于根和叶，BnaMYB28 在茎和种子中的表 达水平更高；BnaMYB28 基因在根肿菌和外源水杨酸处理下均有不同程度的表达响应，外源水杨酸处理下Bna⁃ MYB28-1 和BnaMYB28-3 上调表达，BnaMYB28-2 表达则受抑制。根肿菌侵染后，BnaMYB28-1 在整个侵染期表达 量均显著上调，但在加入水杨酸后表达被显著抑制；BnaMYB28-3 表达量在接菌后7 d和28 d显著上调，在关键皮层 侵染期（接菌后14 d）表达量与对照组相比没有变化，但在施加水杨酸处理后表达量显著上调。综上，外源水杨酸能 正向调控BnaMYB28-1 和BnaMYB28-3 表达，BnaMYB28-3 可能通过水杨酸信号路径参与油菜与根肿菌的互作。     

Dynamics of nitrogen translocation from mature leaves to new shoots and related gene expression during spring shoots development in tea plants (Camellia sinensis L.)

The contribution of N remobilization is crucial for new shoots growth and quality formation during spring tea shoots development. However, the translocation mechanism of N from source leaves to sink young shoots is not well understood. In the present study, ¹⁵N urea was applied to mature tea leaves one week before bud break to track N remobilization in a field experiment. The dynamic changes in plant ¹⁵N abundance, contents of amino acids, and the expression levels of genes related to N metabolism and translocation were followed during the 18‐d development of new spring shoots until three expanding young leaves. The results showed that during the growth of new shoots the amount of ¹⁵N in the shoots increased, whereas the N_dff (N derived from ¹⁵N‐urea) in mature leaves decreased, showing that the foliar‐applied N in mature leaves was readily exported to new shoots. This process was found to be accompanied by decline of chlorophylls. In the mature leaves, expression CsATG18a and CsSAG12 involved in autophagy was dramatically induced (> 4‐fold) at approximately nine days after the bud breaking. The genes involved in the transformation of amino acids, including primarily CsGDH2, CsGDH4, CsGLT3, CsGS1;3, and CsASN2 were upregulated by > 3‐fold after bud breaking. The expression levels of CsATG8A, CsATG9, CsSAG12, CsGS1;1, CsGDH1, and CsAAP6 correlated negatively with the N_dff in mature leaves, but positively with ¹⁵N amount and total N amount in new shoots, suggesting these genes played important roles in N export from mature leaves. In the new shoots, the expression of most genes showed two defined peaks, one on six days and one on 12 days after bud breaking. The expression of CsGS2, CsASN3, CsGLT1, and CsAAP4 positively correlated with the ¹⁵N amount and total N amount in new shoots. These genes might be involved in the transport and re‐assimilation of N from mature leaves. The overall results demonstrated that the translocation of ¹⁵N from mature leaves to new spring shoots was regulated by the genes involved in autophagy, protein degradation, amino acid transformation and transport.     

Role of chlorogenic acid in endothelial dysfunction in db/db mice

AIM: To explore the effects of chlorogenic acid (CGA) on endothelial dysfunction in db/db mice and the possible mechanism. METHODS: Male db/db mice (n=12) were divided into control group and CGA group, with 6 mice in each group. The mice in CGA group were treated with diet containing 0.02% CGA, while the mice in control group were given normal diet only. The observation period was 12 weeks. Fasting blood glucose level, tail blood pressure and the body weight were analyzed each week. At the end of the 12th week, the mice were anesthetized and blood was taken from carotid artery. The plasma levels of heme oxygenase-1 (HO-1), catalase (CAT), NAD(P)H dehydrogenase quinone 1 (NQO1) and glutathione peroxidase-1 (GPx-1) were measured by ELISA. The mouse aortas were isolated, and the superoxide anion and nitric oxide (NO) levels were measured by DHE and DAF-2 DA staining, respectively. Wire Myograph System was used to detect the vasorelaxation of db/db mouse aorta. The protein levels of peroxisome proliferator-activated receptor α (PPARα), nuclear factor E2-related factor 2 (Nrf2), phosphorylated AMP-activated protein kinase (p-AMPK), phosphorylated endothelial NO synthase (p-eNOS), P22^phox and P47^phox were determined by Western blot. RESULTS: Dietary CGA decreased fasting blood glucose and body weight in db/db mice as compared with control group (P<0.01 or P<0.05). The plasma levels of HO-1, CAT, NQO1 and GPx-1 in CGA group were higher than those in control group (P<0.01 or P<0.05). Administration of CGA for 12 weeks attenuated superoxide anion level, increased NO level in the mouse endothelium and improved endothelium-dependent relaxation of the db/db mouse aorta. CGA also increased the protein levels of PPARα, Nrf2, p-AMPK and p-eNOS, and decreased P22^phox and P47^phox levels (P<0.01). CONCLUSION: Dietary CGA improves db/db mouse endothelium-dependent relaxation. This effect may be related to the increases in the levels of antioxidant molecules PPARα, Nrf2 and p-AMPK, and the up-regulation of antioxidant capacity, thus decreasing the oxidative stress, promoting eNOS phosphorylation, and increasing NO level.     

棉籽壳中除草活性物质提取及鉴定

为了开发利用棉籽壳中的除草活性物质，分别以无水乙醇、正丁醇、石油醚和乙酸乙酯为溶剂，采用索氏提取法对棉籽壳中的活性物质进行了提取，并对各溶剂粗提物进行了除草活性测定。结果发现:用无水乙醇提取的粗提物对稗草生长的抑制活性最高，经气相色谱-质谱(GC-MS)联用分析，发现该粗提物中主要含有甘油、三环己基3-烯-6-辛酮、4-乙烯基-2-甲氧基苯酚、(邻甲基苯酚)-2-溴-2氯-乙酰酯、十四酸、十四酸乙酯、十六烷酸、辛酸异戊酯和亚油酸9种化合物。进一步的除草活性测定结果表明，亚油酸、辛酸异戊酯、4-乙烯基-2-甲氧基苯酚和(邻甲基苯酚)-2-溴-2氯-乙酰酯4种化合物对稗草表现出一定的除草活性，其中亚油酸活性最强，其IC₅₀值为14.5 mg/L。     

长江流域生物资源及生态环境研究进展

以CNKI平台中的文献数据,利用文献计量学方法,对其文献的增长趋势及期刊分布进行分析,并基于作者和机构合作网络、关键词共现的聚类知识图谱及突变检测等方法,探究我国长江流域生物资源及生态环境主题的研究热点及其研究前沿。研究表明:研究文献总体上呈递增趋势,2016年开始呈现激增态势;作者、机构间的交流合作较少,作者间合作大部分局限在机构内部的研究者之间的合作,合作相对活跃的机构主要有长江科学院、长江流域水资源保护局及长江水利委员会等;其优势学科领域主要为环境科学、区域经济学、水利工程学、农业经济等。当前我国长江流域生物资源及生态环境的研究领域有5个方向:(1)开展长江经济带城市群生态环境评价与保护、城镇化与生态文明建设,以及绿色发展等研究;(2)开展长江三峡与三峡库区的生态环境监测与保护、森林资源养护、水土保持与流失、资源与生态补偿机制研究及其生态环境的可持续发展等研究;(3)开展长江流域自然保护区的生态环境保护与规划、生态保护红线及其生物资源养护与生物多样性保护等研究;(4)在长江大保护背景下,开展长江流域生态环境的保护与修复、流域综合治理,以及水生生物资源的合理开发利用的研究;(5)开展长江源区水电资源开发、水环境保护及其渔业生态环境保护等研究。为科学管理和保护长江流域的重要生物资源,提出建立基于科学设计的全流域生物资源和环境监测系统,建立全流域的生物资源及生态系统的生物数据模型,发展长江流域渔业资源养护与开发的风险评估决策系统,发展长江流域科学的渔业资源增殖放流技术体系,发展基于GIS的长江全流域的渔业资源与环境监测和管理决策信息服务系统等建议。