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1.
Foods ; 9(3)2020 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-32121041

RESUMO

Impacts of wheat flour substituted with various levels of Chinese yam (Dioscorea opposita Thunb.) flour (from 0% to 25%) on the dough rheological characteristics, gluten structure, baking performance, and antioxidant properties of bread were investigated. The water absorption increased significantly (p < 0.05), while development time and stability decreased remarkably (p < 0.05) as the proportion of yam flour increased. SEM results indicated that the addition of yam flour destroyed the gluten network structure in the dough. Fourier Transform Infrared Spectroscopy (FTIR) spectra showed that addition of yam flour decreased the content of α-helix and ß-sheet in gluten. With the increase in the proportion of yam flour, the specific volume and overall acceptability decreased (p < 0.05) whereas the total phenolics content (TPC), polysaccharides content, total flavonoids content (TFC), allantoin content, The 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging capability, fractal dimension, and hardness increased (p < 0.05). Overall, breads made of wheat flour replacement with no more than 15% Guihuai number 2 yam flour were of a high quality and had more antioxidant properties. These showed that Guihuai number 2 had broad application prospects in baked products.

2.
Ying Yong Sheng Tai Xue Bao ; 30(1): 251-258, 2019 Jan 20.
Artigo em Chinês | MEDLINE | ID: mdl-30907547

RESUMO

We examined the effect of white + red (WR), white + blue (WB), white + green (WG), white + purple (WP) on the carbon-nitrogen metabolism, growth and quality of Chinese chives, with ‘Pingjiu 2’ as the material and white light (W) as the control. The results showed that photosynthetic rate (Pn) in WR treatment was significantly higher than that in the control (CK) and that there was no difference among WB, WG, WP and CK. The activity of RuBPCase in all the four treatments was higher than that in CK. Compared with other treatments, WR showed the highest total sugar content, then WP, with WB and WG showing the lowest. Compared with CK, sucrose phosphate synthase (SPS) activity in WR was higher, and lower in the other three treatments, especially the lowest in WB. WB showed the highest activity of sucrose synthetase (SS) and amylase (AMS), WR displayed the lowest as well as the similar or lower in WG or WP compared with CK. These results implied that the increases of the proportion of red and purple light could improve carbon assimilation and transformation and thus accelerate sugar accumulation of Chinese chives. The content of total nitrogen, protein nitrogen, the activities of NR, GS and GOGAT of WB were the highest among all the treatments. The GDH activity of WB was the lowest and notably lower compared with CK. WR showed the lower contents of total nitrogen, protein nitrogen, the activities of NR and GS, and higher activities of GOGAT and GDH than those in CK, while the GDH activity of WR was the highest. WG showed lower total nitrogen, no-protein nitrogen content, and GDH activity, but higher protein nitrogen, NR and GOGAT activities than those in CK. Compared with the control, WP showed the similar results as WG, besides the higher GS activity, with most of these parameters in WP being better than in WG. These results indicated that blue, purple and green light could promote nitrogen metabolism, while red light might inhibit protein synthesis in Chinese chives. The growth of Chinese chives was much better under red and purple light, but worse under blue light, which led to thinner leaves and lower growth mass. Chinese chives of WP with the lowest crude fiber content showed the optimal comprehensive quality. Therefore, purple light exhibited the best effect on the growth of Chinese chives.


Assuntos
Carbono/metabolismo , Cebolinha-Francesa/fisiologia , Nitrogênio/metabolismo , China , Fotossíntese , Folhas de Planta
3.
Ying Yong Sheng Tai Xue Bao ; 29(11): 3649-3657, 2018 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-30460812

RESUMO

To explore the effects of different light quality ratios on the growth and development of purple lettuce, we used LED intelligent light control console as light source to study the effects of adding different proportions of red and blue light (1:1, 2:1, 4:1 and 1:2) to the white light on photosynthetic characteristics and commercial quality of purple lettuce (Lactuca sativa L. cv 'Zhongshu Purple Lettuce'). The results showed that when the ratio of red to blue light was 4:1, the chlorophyll content, RuBP carboxylase activity, electron transport efficiency of photosynthesis, net photosynthetic rate and growth were all significantly higher than that in control and other treatments, whereas the nitrate content was the lowest. When the ratio of red to blue light was 1:2, the contents of soluble protein, vitamin C, secondary metabolites such as anthocyanins, flavonoids, total phenolic compounds, and the contents of antioxidant capacity were significantly higher than those in the control and other treatments. We concluded that adding appropriate ratios of red to blue light to the white light could increase photosynthesis and improve commercial quality of purple lettuce.


Assuntos
Lactuca/fisiologia , Luz , Fotossíntese , Clorofila , Folhas de Planta
4.
Ying Yong Sheng Tai Xue Bao ; 28(4): 1237-1245, 2017 Apr 18.
Artigo em Chinês | MEDLINE | ID: mdl-29741321

RESUMO

Using split plot and then-split plot design, effects of water-nitrogen coupling on photosynthesis and ultrastructure of cucumber (Cucumis sativus) (Jinyou No.35) under CO2 enrichment were investigated. The main plot had two CO2 concentrations: ambient CO2 concentration (400 µmol·mol-1, A) and doubled CO2 concentration (800±20 µmol·mol-1, E). The split plot had two treatments: no drought stress (95% of field capacity, W) and drought stress (75% of field capacity, D). The then-split plot contained low nitrogen treatment (450 kg·hm-2, N1) and high nitrogen treatment (900 kg·hm-2, N2). The results showed that under the condition of drought and high nitrogen, increasing CO2 enhanced the cucumber plant height, and no matter what kinds of water treatment, CO2 enrichment increased the leaf area significantly under high nitrogen. Under the condition of normal irrigation, the photosynthetic rate, stomatal conductance and transpiration rate of high nitrogen treatment were higher than low nitrogen treatment, while it was under the drought condition. Elevated CO2 enhanced the water use efficiency of cucumber leaf which increased with increasing nitrogen application rate. Under drought stress, cucumber adaxial surface porosity density was increased, and the CO2 enrichment and high nitrogen significantly reduced the stomatal density. Increasing nitrogen application improved the number of chloroplast, and reduced that of starch grains. Drought stress decreased the number of chloroplast, but tended to promote the number of starch grains. Drought stress increased the chloroplast length and width, and the size of the starch grains, while high nitrogen reduced the length and width of the chloroplast and starch grains. CO2 enrichment and high nitrogen increased grana thickness and layers (except ADN2), and the slice layer of EDN2 was significantly higher than that of ADN2. In conclusion, CO2 enrichment and suitable water and nitrogen could promote the development of chloroplast thylakoid membrane system, significantly increase the thickness of grana and the number of grana lamella, and effectively improve the chloroplast structure of cucumber, which would benefit the photosynthesis of cucumber plants and ability to utilize CO2 and water and nitrogen.


Assuntos
Cucumis sativus , Nitrogênio , Fotossíntese , Dióxido de Carbono , Folhas de Planta , Água
5.
Sci Rep ; 6: 34455, 2016 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-27686324

RESUMO

Ultraviolet-B radiation (UV-B) is generally considered to negatively impact the photosynthetic apparatus and plant growth. UV-B damages PSII but does not directly influence PSI. However, PSI and PSII successively drive photosynthetic electron transfer, therefore, the interaction between these systems is unavoidable. So we speculated that UV-B could indirectly affect PSI under chilling-light conditions. To test this hypothesis, the cucumber leaves were illuminated by UV-B prior or during the chilling-light treatment, and the leaves were then transferred to 25 °C and low-light conditions for recovery. The results showed that UV-B decreased the electron transfer to PSI by inactivating the oxygen-evolving complex (OEC), thereby protecting PSI from chilling-light-induced photoinhibition. This effect advantages the recoveries of PSI and CO2 assimilation after chilling-light stress, therefore should minimize the yield loss caused by chilling-light stress. Because sunlight consists of both UV-B and visible light, we suggest that UV-B-induced OEC inactivation is critical for chilling-light-induced PSI photoinhibition in field. Moreover, additional UV-B irradiation is an effective strategy to relieve PSI photoinhibition and yield loss in protected cultivation during winter. This study also demonstrates that minimizing the photoinhibition of PSI rather than that of PSII is essential for the chilling-light tolerance of the plant photosynthetic apparatus.

6.
Ying Yong Sheng Tai Xue Bao ; 27(12): 3996-4002, 2016 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-29704360

RESUMO

To investigate the effect of calcium and ABA on photosynthesis and the activities of antioxidant enzymes in cucumber seedlings under drought stress, the cucumber was used as the expe-riment materials, normal nutrient solution culture was considered as the control, and PEG-6000 application in the nutrient solution simulated the drought stress. There were five different treatments which were spraying water, ABA, CaCl2+ABA, LaCl3(calcium channel inhibitor)+ABA and EGTA (calcium ion chelating agent)+ABA under drought stress. The results showed that drought stress inhibited the growth of cucumber seedlings, and reduced the activities of antioxidant enzymes, nitrate reductase, net photosynthetic rate and fluorescence parameters of the cucumber seedlings leaves. The application of ABA reduced the inhibition of activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT) and ascorbate peroxidase (APX), photosynthesis (Pn, gs) and the fluorescence parameters (Fv'/Fm', qP and ETR), and decreased the damage of drought stress on plant. Spraying CaCl2+ABAsignificantly promoted the positive effect of ABA, while EGTA+ABA and LaCl3 +ABA didn't show the promoting effect.


Assuntos
Cálcio/química , Cucumis sativus/fisiologia , Secas , Fotossíntese , Antioxidantes , Ascorbato Peroxidases , Catalase , Cucumis sativus/enzimologia , Peroxidases , Folhas de Planta , Plântula , Superóxido Dismutase
7.
Ying Yong Sheng Tai Xue Bao ; 27(7): 2308-2314, 2016 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-29737140

RESUMO

In the present work, transgenic cucumber seedlings over expressing CsRCA and wild-type cucumber seedlings '08-1'at three-leaf stage exposed to high temperature (40 ℃, PFD 600 µmol· m-2 · s-1) were used to study the regulatory mechanism of photosynthesis by CsRCA. The results showed that the mRNA abundance of rbcL and rbcS as well as the activities of ribulose bisphosphate carboxylic enzyme (Rubisco) and Rubisco activase (RCA) were significantly higher in CsRCA over-expressing cucumber seedlings than in wild type (WT). Following 2-h exposure to high temperature, a notable decrease was observed in photosynthetic rate (Pn), photochemical perfor-mance index based on the absorption of light energy (PIABS), activities of Rubisco and RCA as well as the relative expression of rbcL, rbcS and CsRCA in both wild-type cucumber seedlings and transgenic cucumber seedlings. It was found that high temperature stress led to higher Wk, a parameter of chlorophyll (Chl) a fluorescence OJIP curve. Furthermore, high temperature greatly reduced the efficiency of electron transfer along the electron transport chain beyond QA(ψ0) and the quantum yield for electron transport (φE0), indicating that PSII oxygen complexes (OEC) and electron transport chain downstream QA were inhibited by high temperature. However, the inhibition could be alleviated by over expressing CsRCA in cucumber seedlings. Taken together, our data suggested that over expressing CsRCA improves photosynthesis in cucumber seedlings under high temperature stress by enhancing activities of the Rubisco and RCA, and maintaining the number of active reaction centers.


Assuntos
Cucumis sativus/fisiologia , Temperatura Alta , Fotossíntese , Proteínas de Plantas/genética , Clorofila , Clorofila A , Cucumis sativus/genética , Transporte de Elétrons , Plantas Geneticamente Modificadas/fisiologia , Ribulose-Bifosfato Carboxilase , Plântula , Estresse Fisiológico
8.
Ying Yong Sheng Tai Xue Bao ; 26(8): 2314-20, 2015 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-26685593

RESUMO

In order to explore the effects of NO3- stress on photosynthetic characteristics and nitrogen metabolism, strawberry seedlings were grown in sand culture condition under different concentrations of NO3- (64, 112 and 160 mmol · L(-1)) with the control of 16 mmol NO3- · L(-1). The results indicated that at the 8th day after treatment, with the increased NO3- concentration, the strawberry leaf net photosynthetic rate (Pn), stomatal conductance (g(s)), PS II actual photochemical efficiency (ΦPS II), PS II maximum photochemical efficiency (Fv/Fm), and photochemical quenching coefficient (q(P)) significantly decreased, and decreased by 67.7%, 68.4%, 35.7%, 23.2% and 26.9%, respectively, when NO3- concentration reached 160 mmol · L(-1) compared with the control. The non-photochemical quenching coefficient (q(N)) increased by 4.4%, 10.9% and 75.8% respectively in the treatments of 64, 112 and 160 mmol NO3- · L(-1) compared with the control. The intercellular CO2 concentration (Ci) decreased under low NO3- concentration stress and then increased under high NO3- concentration stress, while the stomatal limitation (Ls) was vice versa. With the increased NO3- concentration, the nitrate nitrogen, ammonia nitrogen, total nitrogen and Kjeldahl nitrogen contents in the strawberry leaves and roots increased, but the protein nitrogen content decreased. The activities of nitrate reductase (NR) , glutamine sybthetase (GS), glutamate synthase (GOGAT) and glutamate dehydrogenase (GDH) increased at low NO3- concentration and then decreased at high NO3 concentration. Consequently, the net photosynthetic rate of strawberry seedling leaves decreased, the PS II electron transfer was blocked, the nitrogen accumulated with the increasing NO3- concentration, and the nitrogen metabolism enzyme activity decreased at high NO3- concentrations. When the NO3- concentration reached 64 mmol · L(-1) or higher in the nutrient solution, the growth of strawberry seedlings were inhibited significantly.


Assuntos
Fragaria/fisiologia , Nitratos/metabolismo , Nitrogênio/metabolismo , Fotossíntese , Transporte de Elétrons , Glutamato Desidrogenase/metabolismo , Glutamato Sintase/metabolismo , Glutamato-Amônia Ligase/metabolismo , Nitrato Redutase/metabolismo , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , Plântula/fisiologia , Estresse Fisiológico
9.
Sci Rep ; 5: 13094, 2015 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-26471979

RESUMO

Although root-to-shoot communication has been intensively investigated in plants under drought, few studies have examined root-to-shoot communication under chilling. Here we explored whether root-to-shoot communication contributes to the chilling-light tolerance of cucumber shoots and clarified the key signal involves in this communication. After leaf discs chilling-light treatment, the photoinhibitions of Photosystem I (PSI) and Photosystem II (PSII) were similar in leaf discs of two cucumber varieties (JY-3 and JC-4). When the whole plants, including roots, were chilled under light, the photosynthetic performances in JC-4 leaves decreased more seriously than that in JY-3 leaves. However, when the water status of leaves was maintained by warming roots or floating the attached leaves on water, the PSII activity and amount of PSI in the leaves of the two varieties were similar after chilling-light treatment. In addition, the differences of PSII activities and amount of PSI between the two varieties under whole plant chilling-light treatment were independent of ABA pretreatment. Above results indicate that (1) the better water status in leaves under chilling contributes to the higher chilling tolerance of JY-3; (2) the water status, rather than an ABA signal, dominates root-to-shoot communication under chilling and the chilling tolerance of cucumber shoot.


Assuntos
Adaptação Biológica , Temperatura Baixa , Cucumis sativus/fisiologia , Raízes de Plantas , Brotos de Planta , Água , Luz , Fotossíntese , Folhas de Planta , Plântula
10.
Ying Yong Sheng Tai Xue Bao ; 26(1): 53-60, 2015 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-25985653

RESUMO

The effects of doubled CO2 concentration on non-structural carbohydrate metabolism of cucumber (Cucumis sativus L. cv. 'Jinyou No.1') seedlings under drought stress were investigated. Split plot design was deployed, with two levels of CO2 concentrations (ambient CO2 concentration, 380 µmol . mol-1, and doubled CO2 concentration, 760±20 µmol . mol-1) in the main plots, and three levels of water treatments (control, moderate drought stress, and severe drought stress) simulated by PEG 6000 in the split-plots. The results showed that non-structural carbohydrates of cucumber leaves, including glucose, fructose, sucrose, and stachyose, increased with the doubling of CO2 concentration, which resulted in the decreased osmotic potential, improving the drought stress in cucumber seedlings. During the drought stress, sucrose synthase, soluble acid invertase and al- kaline invertase started with an increase, and followed with a decline in the leaves. In the root system, however, soluble acid invertase and alkaline invertase increased gradually throughout the whole process, whereas sucrose phosphate synthase firstly increased and then decreased. The treatment of doubled CO2 enhanced the activity of sucrose synthase, but decreased the activity of sucrose phosphate synthase. The synergistic action of the two enzymes and invertase accelerated the decomposition of sucrose and inhibited the synthesis of sucrose, leading to the accumulation of hexose, which lowered the cellular osmotic potential and enhanced the water uptake capacity. In conclusion, doubled CO2 concentration could alleviate the adverse effects of drought stress and improve the drought tolerance of cucumber seedlings. Such mitigating effect on cucumber was more significant under severe drought stress.


Assuntos
Metabolismo dos Carboidratos , Dióxido de Carbono/química , Cucumis sativus/metabolismo , Secas , Plântula/metabolismo , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , Estresse Fisiológico , Sacarose/metabolismo , Água , beta-Frutofuranosidase/metabolismo
11.
Ying Yong Sheng Tai Xue Bao ; 24(6): 1669-76, 2013 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-24066556

RESUMO

From December 2011 to March 2012, a consecutive test was conducted on the temperature and heat flux of different thickness of the soil backwall of sunken solar greenhouse in Shouguang of Shandong Province, East China, aimed to analyze the variation patterns of soil wall temperature and heat flux of the sunken solar greenhouse and to confirm the suitable wall thickness. In winter, the temperature and heat flux of the wall inner surface and outer surface varied over a wide range, which was in accordance with the variation trend of indoor and outdoor air temperature. Overall, the wall temperature decreased from the inner to the outer surface, and the layers of the inner wall with higher variation range of temperature and heat flux were more than those of the outer wall. The variation range of temperature and heat flux decreased gradually from the shallow layers to deep layers of the wall. In successive cloudy days, the temperature of each layer of inner wall decreased to different degrees, and the layers releasing heat to the indoor deepened constantly, whereas the heat in the layers of outer wall was mainly released to the outdoor. According to the variation patterns of temperature and heat flux in the wall, the wall from inside to outside could be divided into heat storage layer, transitional layer, and cold resistant layer, and their thickness was 0.8-1.0 m, 2.2-2.6 m, and 0.4-0.6 m, respectively, under the condition of the outer surface being covered. Without considering the transitional layer, the suitable thickness of the soil wall in Shouguang solar greenhouse would be 1.4-1.6 m.


Assuntos
Agricultura/métodos , Ambiente Controlado , Energia Solar , Temperatura , China , Ecossistema , Solo
12.
J Nat Prod ; 75(11): 1994-8, 2012 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-23095059

RESUMO

Griseusins F (1) and G (2), two 2a-hydro-8a-(2-oxopropyl)-substituted spiro-naphthoquinones with a previously undescribed C23 polyketide skeleton, were isolated from a Yunnan tin mine tailings-derived alkalophilic actinomycete, Nocardiopsis sp. YIM DT266. Their complete structure assignments with the absolute stereochemistry were elucidated by spectroscopic data, X-ray crystal diffraction, calculation of optical rotation, and CD spectroscopic analysis. Compounds 1 and 2 exhibited strong cytotoxicity (IC50 0.37-0.82 µM) and antibacterial activity (MIC 0.80-1.65 µg/mL) against Gram-positive bacteria, including methicillin-resistant Staphylococcus aureus (MRSA) in vitro.


Assuntos
Antibacterianos/isolamento & purificação , Nocardia/química , Antibacterianos/química , Antibacterianos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Bactérias Gram-Positivas , Células HCT116 , Humanos , Staphylococcus aureus Resistente à Meticilina , Testes de Sensibilidade Microbiana , Estrutura Molecular , Naftoquinonas/química , Naftoquinonas/isolamento & purificação , Naftoquinonas/farmacologia
13.
Zhonghua Yi Xue Za Zhi ; 92(37): 2607-10, 2012 Oct 09.
Artigo em Chinês | MEDLINE | ID: mdl-23290060

RESUMO

OBJECTIVE: To explore the relationship between the protection of hydrogen sulfide (H(2)S) against hepatic ischemia-reperfusion injury and thioredoxin system in rats. METHODS: Eighteen adult rats were divided randomly into 3 groups, i.e. sham, ischemia-reperfusion (IR) and sodium hydrogen sulfide (NaHS). The rats in the IR and NaHS groups were subjected to ischemia for 60 min and followed by reperfusion for 6 hours. In the NaHS group, there was an intraperitoneal dosing of NaHS (28 µmol/kg) at 5 min pre-reperfusion. Blood samples were collected for the measurements of alanine transaminase (ALT) and aspartate transaminase (AST). Liver tissue samples were collected for measurements of Trx and TrxR activity by enzyme-linked immunosorbent assay (ELISA), Western blot detection of Trx system proteins and thioredoxin interacting protein (TXNIP) expression. Hematoxylin-eosin staining was used to observe the hepatic histopathological changes. RESULTS: Compared with the sham group, increased activities of ALT and AST were found in the IR group, accompanied by aggravated pathological injury. In addition, NaHS administrated at pre-reperfusion could alleviate hepatic injury. Compared with the sham group, the IR group had decreased Trx activity and Trx1 protein expression and increased TXNIP protein expression (P < 0.05) while the NaHS group had increased Trx activity and Trx1 protein expression and decreased TXNIP protein expression (P < 0.05). It indicated that the postconditioning with H(2)S could reduce the inhibition of Trx system and boost tissue antioxidant capacity. CONCLUSION: Hydrogen sulfide postconditioning can enhance the cellular Trx system and play a protective role in hepatic ischemia-reperfusion injury.


Assuntos
Sulfeto de Hidrogênio/farmacologia , Pós-Condicionamento Isquêmico , Traumatismo por Reperfusão/metabolismo , Tiorredoxinas/metabolismo , Animais , Sulfeto de Hidrogênio/metabolismo , Fígado/irrigação sanguínea , Masculino , Ratos , Ratos Sprague-Dawley
14.
Ying Yong Sheng Tai Xue Bao ; 22(8): 2061-8, 2011 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-22097368

RESUMO

Taking the energy-saving solar greenhouses with the same infrastructure but different sunken depths (0, 0.5, 1.0, and 1.5 m) in Tai' an of Shandong Province as test objects, this paper analyzed the intercepted amount of direct solar radiation energy, and studied the diurnal variation and spatial distribution patterns of environmental factors in the greenhouses on winter solstice (December 20-24, 2009) and summer solstice (June 19-23, 2010). With the increase of sunken depth, the shadow areas in the greenhouses caused by sunken profiles increased gradually, the direct solar radiation energy into the interior of the greenhouses shifted from south to north, and the ratio of ground radiation to back wall radiation decreased gradually. Within the range of 0-1.0 m sunken depth, the air temperature and soil temperature in the greenhouses increased significantly with increasing sunken depth; but when the sunken depth was 1.5 m, the warming effect declined significantly, and the deviation of the lowest soil temperature increased. The deeper the sunken depth, the lower the light intensity and the higher the relative humidity in the greenhouses were. In considering of both lighting and heat preservation, the appropriate sunken depth of energy-saving sunlight greenhouses with a span of 10 m in Tai' an region should be less than 1.0 m.


Assuntos
Agricultura/métodos , Monitoramento Ambiental/métodos , Energia Solar , Verduras/crescimento & desenvolvimento , China , Ritmo Circadiano , Ecossistema , Ambiente Controlado
15.
Ying Yong Sheng Tai Xue Bao ; 21(5): 1289-94, 2010 May.
Artigo em Chinês | MEDLINE | ID: mdl-20707115

RESUMO

Taking 'Chifengtexuan' as scion and 'Weishi' as rootstock, this paper studied the changes in the electrolyte leakage (EL), malondialdehyde (MDA) content, antioxidative enzyme activities, and root activity of own-rooted and grafted Capsicum annuum seedlings under 1-7 days low temperature (8 degrees C/ 5 degrees C) and weak light intensity (100 micromol x m(-2) x s(-1) stress and after 1-3 d recovery. During the early stress days, the EL, MDA content, and activities of superoxide dismutase (SOD), peroxidase (POD), ascorbate peroxidase (APX) and glutathione reductase (GR) in both own-rooted and grafted seedlings leaves and roots increased, but the root activity decreased significantly. 1-3 days later, grafted seedlings showed a stable state in EL and MDA content, a decrease in SOD, POD, APX, and GR activities, and an increasing trend in root activity. After 3 days recovery, the EL, MDA content, antioxidative enzyme activities, and root activity of grafted seedlings reached or exceeded their original levels, except for the MDA content in roots, while the EL and MDA content of own-rooted seedlings were still significantly higher than those before the stress. Comparing with own-rooted seedlings, grafted seedlings showed lower EL and MDA content, higher activities of SOD, POD, APX and GR, and higher root activity during stress and recovery days. These data suggested that graft could effectively decrease the lipid peroxidation, and alleviate the damage of low temperature and weak light intensity to Capsicum annuum seedlings.


Assuntos
Agricultura/métodos , Capsicum/metabolismo , Temperatura Baixa , Peroxidação de Lipídeos/fisiologia , Superóxido Dismutase/metabolismo , Capsicum/enzimologia , Capsicum/crescimento & desenvolvimento , Plântula/enzimologia , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Luz Solar
16.
J Phys Condens Matter ; 22(31): 315304, 2010 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-21399360

RESUMO

We study the band and transport features of zigzag graphene nanoribbon with an antidot lattice. It is found that an antidot lattice could turn semi-metal graphene into a semiconductor. The size of the band gap can be tuned by the position of the antidots and the distance D between the two nearest antidots. For a finite superlattice with N antidots and a large D, a group of (N - 1) splitting resonant peaks and transmission-blockade regions appear alternately in the conductance spectrum. This indicates the formation of minibands and minigaps. In addition, Fano resonances can be observed when the antidots are localized near one edge of the nanoribbon. These features provide potential applications for graphene-based electronic and optoelectronic devices.

17.
J Integr Plant Biol ; 50(10): 1307-17, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19017118

RESUMO

To reveal and quantify the interactive effects of drought stresses and elevated CO2 concentration [CO2] on photochemistry efficiency of cucumber seedlings, the portable chlorophyll meter was used to measure the chlorophyll content, and the Imaging-PAM was used to image the chlorophyll fluorescence parameters and rapid light response curves (RLC) of leaves in two adjacent greenhouses. The results showed that chlorophyll content of leaves was reduced significantly with drought stress aggravated. Minimal fluorescence (Fo) was increased while maximal quantum yield of PSII (Fv/Fm) decreased significantly by severe drought stress. The significant decrease of effective quantum yield of PSII (Y(II)) accompanied by the significant increase of quantum yield of regulated energy dissipation (Y(NPQ)) was observed under severe drought stress condition, but there was no change of quantum yield of nonregulated energy dissipation (Y(NO)). We detected that the coefficient of photochemical quenching (qP) decreased, and non-photochemical quenching (NPQ) increased significantly under severe drought stress. Furthermore, we found that maximum apparent electron transport rate (ETR(max)) and saturating photosynthetically active radiation (PPFD(sat)) decreased significantly with drought stress aggravated. However, elevated [CO2] significantly increased Fv/Fm, qP and PPFD(sat), and decreased NPQ under all water conditions, although there were no significant effects on chlorophyll content, Fo, Y(II), Y(NPQ), Y(NO) and ETR(max). Therefore, it is concluded that CO2-fertilized greenhouses or elevated atmospheric [CO2] in the future could be favorable for cucumber growth and development, and beneficial to alleviate the negative effects of drought stresses to a certain extent.


Assuntos
Dióxido de Carbono/toxicidade , Cucumis sativus/efeitos dos fármacos , Cucumis sativus/metabolismo , Secas , Fotossíntese/fisiologia , Plântula/metabolismo , Clorofila/metabolismo , Fotossíntese/efeitos dos fármacos , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Plântula/efeitos dos fármacos
18.
Zhong Yao Cai ; 29(5): 456-8, 2006 May.
Artigo em Chinês | MEDLINE | ID: mdl-16981458

RESUMO

OBJECTIVE: To investigate the anti-proliferation effect of WEI KANG NING on gastric cancer. METHODS: MGC-803 cells were cultured in different concentrations of serum containning WEI KANG NING. The inhibitory ratio of the cells was measured by MTT assay. Apoptosis was observed by Hoechst 33258 fluorescence staining. RESULTS: Each concentration of serum containning WEI KANG NING could inhibit cells proliferation. Among them, both high and medium concentration could inhibit longer. Moreover, high concentration could induce cells apoptosis. CONCLUSION: WEI KANG NING serum has anti-proliferation effect on MGC-803 cells and the effect may be related to cell apoptosis induced by WEI KANG NING.


Assuntos
Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Plantas Medicinais/química , Neoplasias Gástricas/patologia , Animais , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Combinação de Medicamentos , Medicamentos de Ervas Chinesas/administração & dosagem , Masculino , Ratos , Ratos Wistar
19.
Zhong Yao Cai ; 29(4): 341-5, 2006 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-16913488

RESUMO

OBJECTIVE: To observe the effect of containing drugs serum of weikanguing decoction (WKN) on expression of Cyclin E, CDK2 (Cyclin dependant kinase 2, CDK2) and p27 in gastric cancer cell line MGC-803. METHODS: Total of 120 male Wistar rats were divided into control group, high dose group, medium dose group and low dose group fed with natural saline, 20,10, and 5 g/kg of WKN, respectively. The experimental animals were finally killed for the preparation of drug-containing serum. The gastric cancer cell MGC-803 was cultured with the drug-containing serum drawn from the rats in different groups. The expression of Cyclin E, CDK2 and p27 was detected with immunohistochemistry method-SABC. The expression of mRNA of Cyclin E, CDK2 and p27 were detected with RT-PCR. RESULTS: In high, medium and low dose groups, the gray scales of cyclin E, CDK2 and the OPDTI values of p27 increased significantly, but the gray scales of p27 and the OPDTI values of cyclin E, CDK2 decreased remarkble, compared with that in control group. CONCLUSION: The decoction of WKN can decrease the expression of Cyclin E, CDK2, increases the expression of p27. This effect may be involved in mechanism of gastric cancer cell growth inhibition induced by WKN.


Assuntos
Ciclina E/metabolismo , Quinase 2 Dependente de Ciclina/metabolismo , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Neoplasias Gástricas/patologia , Animais , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/farmacologia , Ciclo Celular , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ciclina E/genética , Quinase 2 Dependente de Ciclina/genética , Inibidor de Quinase Dependente de Ciclina p27/genética , Relação Dose-Resposta a Droga , Combinação de Medicamentos , Medicamentos de Ervas Chinesas/administração & dosagem , Imuno-Histoquímica , Masculino , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias Gástricas/metabolismo
20.
Zhong Xi Yi Jie He Xue Bao ; 4(1): 48-51, 2006 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-16409970

RESUMO

OBJECTIVE: To investigate the effects of Naohuandan Recipe on learning and memory abilities of SAM-P/8 mice and its role in anti-oxidation and anti-apoptosis. METHODS: Forty SAM-P/8 mice were randomly divided into four groups, which were untreated (normal saline-treated) group, Yinkeluo Tablets (extracts of gingko leaf)-treated group, low-dose Naohuandan Recipe-treated group and high-dose Naohuandan Recipe-treated group. Mice in these groups were given corresponding drugs orally for 105 days. Then the performances of learning and memory of mice were tested by a step-down passive avoidance task and a Y-maze test. The serum levels of superoxide dismutase (SOD), malondialdehyde (MDA) and glutathione peroxidase (GSH-Px) were detected. The expression level of bcl-xl mRNA in cerebral cortex and hippocampus of mice was detected by reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: The performances of learning and memory in the Yinkeluo Tablets-treated group, low- and high-dose Naohuandan Recipe-treated groups were significantly improved as compared with those in the untreated group (P<0.05 or P<0.01), and such performance was the best in the high-dose Naohuandan Recipe-treated group among these four groups (P<0.01). The serum levels of SOD and GSH-Px and the expression of bcl-xl mRNA in cerebral cortex and hippocampus of mice in the Yinkeluo Tablets-treated group, low- and high-dose Naohuandan Recipe-treated groups were also significantly higher than those in the untreated group (P<0.05 or P<0.01), while the serum level of MDA in the untreated group was higher than that in the other three groups (P<0.01). CONCLUSION: Naohuandan Recipe can improve learning and memory abilities of SAM-P/8 mice, and this effect may be related to its anti-oxidation efficacy and enhancement of expression level of bcl-xl mRNA.


Assuntos
Envelhecimento/metabolismo , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Aprendizagem/efeitos dos fármacos , Envelhecimento/genética , Animais , Glutationa Peroxidase/sangue , Memória/efeitos dos fármacos , Camundongos , Camundongos Mutantes/genética , Camundongos Mutantes/metabolismo , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Superóxido Dismutase/sangue , Proteína bcl-X/biossíntese , Proteína bcl-X/genética
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