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941.
Yin-jian ZHENG Yi-ting ZHANG Hou-cheng LIU Ya-min LI Ying-liang LIU Yan-wei HAO Bing-fu LEI 《农业科学学报》2018,17(10):2245-2256
To evaluate the supplementary blue light intensity on growth and health-promoting compounds in pak choi(Brassica campestris ssp.chinensis var.communis),four blue light intensity treatments(T0,T50,T100 and T150 indicate 0,50,100,and 150μmol m~(–2) s~(–1),respectively)were applied 10 days before harvest under greenhouse conditions.Both of cultivars(greenand red-leaf pak choi)under T50 had the highest yield,content of chlorophyll and sugars.With light intensity increasing,antioxidant compounds(vitamin C and carotenoids)significantly increased,while nitrate content showed an opposite trend.The health-promoting compounds(phenolics,flavonoids,anthocyanins,and glucosinolates)were significantly higher under supplementary light treatment than T0,so as the antioxidant capacity(2,2-diphenyl-1-picrylhydrazyl and ferric-reducing antioxidant power).The species-specific differences in photosynthetic pigment and health-promoting compounds was found in green-and red-leaf pak choi.T50 treatment could be used for yield improvement,whereas T100 treatment could be applied for quality improvement.Results showed that blue light intensity can regulate the accumulation of biomass,morphology and health-promoting compounds in pak choi under greenhouse conditions. 相似文献
942.
研究温度对花椒产量和品质指标的影响。以九叶青花椒为试验材料,于2019年5~6月在人工气候室开展盆栽试验,设置2个环境最高温度处理,以29℃和大田花椒为对照,正常采收期取样测定花椒的产量因子和品质指标。结果表明,花椒籽壳比随温度升高而增加,千粒重变化趋势相反,即温度越高皮壳产量越低,千粒重也下降。不同温度环境条件下花椒硒含量差异达到0.05显著水平,CK(大田)>CK(29℃)>T(33℃) >T(36℃),处理温度越高花椒硒含量越低。花椒挥发油、麻味素含量随处理温度升高呈现下降的趋势,即CK(29℃)>T(33℃) >T(36℃),由于人工控制环境日较差10℃大于大田环境日较差7.2℃,较大的日较差更有利于挥发油、麻味素等物质积累,CK(大田)CK(29℃)>T(33℃) >T(36℃)。花椒果实膨大期29℃左右比较适宜花椒产量品质形成,温度过高对于品质和产量的形成具有一定不利影响。 相似文献
943.
Plant volatile organic compounds (VOCs) represent a relatively wide class of secondary metabolites. The VOC profiles of seven seaweeds (Grateloupia filicina, Polysiphonia senticulosa, Callithamnion corymbosum, Sargassum thunbergii, Dictyota dichotoma, Enteromorpha prolifera and Ulva lactuca) from the Yellow Sea of China were investigated using multifiber headspace solid phase microextraction coupled with gas chromatography–mass spectrometry (HS-SPME/GC–MS), among them, the VOCs of three red algae Grateloupia filicina, Polysiphonia senticulosa, and Callithamnion corymbosum were first reported. Principal component analysis (PCA) was used to disclose characteristic categories and molecules of VOCs and network pharmacology was performed to predict potential biomedical utilization of candidate seaweeds. Aldehyde was found to be the most abundant VOC category in the present study and (E)-β-ionone was the only compound found to exist in all seven seaweeds. The chemical diversity of aldehydes in E. prolifera suggest its potential application in chemotaxonomy and hinted that divinylbenzene/carboxen/polydimethylsiloxane (DVB/CAR/PDMS) fiber is more suitable for aldehyde extraction. VOCs in D. dichotoma were characterized as sesquiterpenes and diterpenes and the most relevant pharmacological pathway was the neuroactive ligand–receptor interaction pathway, which suggests that D. dichotoma may have certain preventive and therapeutic values in cancer, especially in lung cancer, in addition to neuropsychiatric diseases. 相似文献
944.
Mateja Colaric Franci Stampar Metka Hudina 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(2):187-192
Abstract The effect of branch bending on the phenolic content in pear leaves was investigated. Leaves were sampled from the tree branches which were bent in summer 2003 (1 September), in spring 2004 (15 May), and from unbent trees. Samplings were made during the growing season May to October 2004, on the following dates: 1st sampling, 15 May; 2nd sampling, 11 June; 3rd sampling, 9 July; 4th sampling, 6 August; 5th sampling, 2 September; and 6th sampling, 1 October. The leaves contained caffeic acid, chlorogenic acid, sinapic acid, syringic acid, vanillic acid, rutin, epicatechin and catechin. The lowest contents of phenolics were found on the first occasion. After that, in the sequence of sampling dates, an increase was noticed at first, but after reaching their highest point, the contents of phenolics decreased. In most cases fewer contents of phenolic compounds were found in leaves from bent branches (especially from branches bent in summer), and the highest ones in leaves from the control group. For all phenolics, apart from the caffeic and vanillic acids, significant differences were evident among treatments, with the highest contents in the control group and almost the lowest in the summer treatment. It is suggested that the change in branch angle caused the physiological response of pear tree, with different contents of phenolic compounds in its leaves from bent and non-bent branches. 相似文献
945.
中华绒螯蟹不同部位中活性香气物质的研究 总被引:3,自引:0,他引:3
运用顶空固相微萃取-气-质联用技术(HS-SPME-GC-MS),对采自崇明的二级雄性中华绒螯蟹体肉、钳肉、足肉和性腺中的香气成分进行了鉴定并以内标法对其定量。大闸蟹四可食部位中共检测到8大类58种香气物质,根据阈值进一步求得每种香气物质的活性值(OAV值)。以OAV值为依据,从58种化合物中筛选得到了癸醛等15种最为关键的活性香气物质,并运用主成分分析法(PCA)和聚类分析法(CA)对其活性值进行了分析。由PCA分析得到:性腺样品香气品质较佳,戊醛等8种为表征"高品质风味"的特征性香气物质(其中2,4-庚二烯醛最为重要)。由CA分析得到:大闸蟹性腺样品可聚为一类,戊醛等8种活性香气成分也可聚为一类。主成分分析和聚类分析结果存在一致性且可以相互补充,今后可利用两种方法建立大闸蟹香气品质的评价模型。 相似文献
946.
Maoxin Zhang Tingting Fang Guilin Pu Xiaoqin Sun Xuguo Zhou Qingnian Cai 《Pesticide biochemistry and physiology》2013
Plant secondary compounds have been documented to be deleterious to insects and other herbivores in diverse ways. In this study, the effect of catechol (phenolics), gramine (alkaloid) and L-ornithine-HCI (non-protein amino acid) on the activities of xenobiotic metabolizing enzymes in English grain aphid, Sitobion avenae, was evaluated. Phase I enzymes investigated in this study included carboxylesterase (CarE), and oxidoreductase, whereas Phase II enzymes were represented by glutathione S-transferase (GST). In general, CarE and GST activities in S. avenae were positively correlated with the concentration of plant secondary compounds in artificial diets. Oxidoreductase activity, however, displayed a different profile. Specifically, peroxidase (POD) and polyphenol oxidase (PPO) activities in S. avenae were positively correlated with concentrations of dietary catechol and gramine, respectively, whereas catalase (CAT) activity was significantly suppressed by the higher concentration of catechol, gramine and L-ornithine-HCl. These combined results suggest that CarE and GST in S. avenae are key enzymes to breakdown a broad spectrum of plant secondary compounds, whereas oxidoreductase, including PPO and POD, degrades specific groups of plant secondary compounds. 相似文献
947.
铁氧化物-胡敏酸复合物对磷的吸附吸附 总被引:1,自引:0,他引:1
本试验通过设置不同磷酸根浓度、 pH和不同电解质及电解质强度梯度,研究磷酸根在针铁矿-胡敏酸(HA)复合物和赤铁矿-胡敏酸(HA)复合物表面的吸附特性。X射线衍射(XRD)、 扫描电镜(SEM)和红外光谱(FTIR)图谱显示: 铁氧化物包覆胡敏酸后其内部结构特性保持不变; 氧化铁与胡敏酸通过氢键形成粒径大、 表面光滑的铁氧化物-HA复合微粒,且复合物比表面减小; 形成的氧化铁-胡敏酸复合物对磷的吸附能力增强,且针铁矿复合物的吸附能力大于赤铁矿复合物,均为多层吸附过程; pH增高抑制铁氧化物复合物对磷的吸附,同时电解质浓度增加促进复合体对磷的吸附,且反应后体系pH随之降低。 相似文献
948.
为探索天然酚类化合物百里香酚、和厚朴酚与化学合成杀菌剂百菌清、啶酰菌胺混配的增效作用,筛选出能够防治灰霉病的混剂,本研究将百里香酚、和厚朴酚分别与百菌清、啶酰菌胺以不同比例混配,采用菌丝生长速率法测定其对灰葡萄孢菌Botrytis cinerea的抑菌活性,并将Bliss法、Mansour法和孙云沛法结合,以优化筛选方案,评价混剂的联合毒力。实验结果表明:将Bliss法、Mansour法和孙云沛法结合使用能够有效降低筛选工作量,且准确率较高;百里香酚和百菌清以质量比5:1、2:3、1:5和1:10比例混配,和厚朴酚和百菌清以质量比10:1、5:1、3:2、2:3和1:10比例混配均表现出协同增效作用;和厚朴酚和百菌清以10:1比例混配时协同增效作用最明显,其CTC值为309.15,以1:10比例混配时抑菌活性最高,其对B. cinerea的EC50为0.29 mg/L,高于杀菌剂百菌清。因此,将定性分析方法与定量分析方法结合使用是筛选杀菌剂混剂配方的合理方案,天然酚类化合物百里香酚、和厚朴酚与百菌清以合理比例混配所得混剂具有防治灰霉病的潜力。 相似文献
949.
Olfa Dabbaghi Meriem Tekaya Naouraz M'barki Sarra Ouled ali Sevgi Öden Mouna Aïachi Mezghani 《Journal of plant nutrition》2013,36(18):2281-2297
Growth and biochemical parameters of leaves, flower buds and flowers of olive (Olea europaea L. cv. Chemlali) treated by foliar biofertilization (T0: untreated trees; T1: rich in nitrogen (N), phosphorus (P), potassium (K); T2: rich in calcium (Ca); T3: application of T1 and T2) were analyzed during the flowering stage. The results showed that T1 resulted in higher contents of leaf N, K, and Na. T1 and T3 resulted in an increase of pigment concentration in leaves. All foliar treatments affected negatively the contents of total polyphenols and orthodiphenols in leaves and flower buds. Lower amounts of individual phenolic compounds were detected in the leaves under all foliar bio-fertilizations and in flower buds of olive trees sprayed with T2 and T3. This decrease is explained by the lower enzymatic activity of l-phenylalanine ammonia-lyase. In flowers, T1 exhibits the highest levels of total polyphenols, o-diphenols, and individual phenolic compounds compared to T0. 相似文献
950.
Marine Bacillus species produce versatile secondary metabolites including lipopeptides, polypeptides, macrolactones, fatty acids, polyketides, and isocoumarins. These structurally diverse compounds exhibit a wide range of biological activities, such as antimicrobial, anticancer, and antialgal activities. Some marine Bacillus strains can detoxify heavy metals through reduction processes and have the ability to produce carotenoids. The present article reviews the chemistry and biological activities of secondary metabolites from marine isolates. Side by side, the potential for application of these novel natural products from marine Bacillus strains as drugs, pesticides, carotenoids, and tools for the bioremediation of heavy metal toxicity are also discussed. 相似文献