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Combining network pharmacology,molecular docking,and experimental verification to investigate the anti-rheumatoid arthritis effect and mechanism of Baeckea frutescens leaves
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作者 Xueyang Guo Mengyao Zhang +6 位作者 Haixia Cai Xinyue Jiang Siyuan Zhou Wen Gong Zijiao Wei Weili Qiao Beixi Jia 《Food Science and Human Wellness》 2025年第7期2723-2737,共15页
The aromatic Baeckea frutescens leaves(BFL)known as“Gang-Song-Cha”is a popular drink(Tea)in South China.To explore the healthcare value,a systematic and in-depth study on BFL alleviating rheumatoid arthritis(RA)was ... The aromatic Baeckea frutescens leaves(BFL)known as“Gang-Song-Cha”is a popular drink(Tea)in South China.To explore the healthcare value,a systematic and in-depth study on BFL alleviating rheumatoid arthritis(RA)was carried out by integrating network pharmacology,molecular docking,and experimental verification.The efficacy was first evaluated,and the BFL extract could ameliorate RA by inhibiting articular swelling,lowering immune organ index,improving the ankle pathologies,and regulating serum levels of tumor necrosis factorα(TNF-α),interleukin(IL)-6,and IL-10 in CIA rats.Then the anti-RA mechanism of BFL was investigated by leveraging the high-content and active component 5-hydroxy-7-methoxy-2-isopropylchromone(Chro),and the potential signaling pathway and related target proteins for Chro acting on RA were analyzed by Kyoto Encyclopedia of Genes and Genomes(KEGG)enrichment and docking simulation.Finally,the experimental validations were conducted on rheumatoid arthritis fibroblast-like synoviocytes(RAFLS),and compound Chro could inhibit cell invasion and migration,block cell cycle at G2/M phase and induce apoptosis,and reduce the secretion of inflammatory cytokines by suppressing the PI3K-Akt pathway.These results provided pharmacological basis for the folk usage of“Gang-Song-Cha”for intervening RA. 展开更多
关键词 Baeckea frutescens leaves Rheumatoid arthritis 5-Hydroxy-7-methoxy-2-isopropylchromone Network pharmacology Molecular docking
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Judgment of Aroma Types of Middle and Upper Flue-cured Tobacco Leaves Based on Stepwise Discriminant Analysis
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作者 詹军 周芳芳 +5 位作者 董石飞 饶智 朱海滨 资文华 蒋美红 罗华元 《Agricultural Science & Technology》 CAS 2014年第9期1550-1557,共8页
[Objective] The aim of this study was to establish mathematical models for judging the aroma types of middle and upper flue-cured tobacco leaves according to the contents and proportions of aroma compositions. [Method... [Objective] The aim of this study was to establish mathematical models for judging the aroma types of middle and upper flue-cured tobacco leaves according to the contents and proportions of aroma compositions. [Method] The aroma types of tobacco leaves were judged based on stepwise discriminant analysis, using 63 C3F and 65 B2F tobacco leaf samples from 13 tobacco producing regions in 11 provinces of China (Huili in Sichuan, Baokang in Hubei, Wulong in Chongqing, Lu- oyang in Henan, Zhucheng in Shandong, Wuyi Mountain in Fujian, Malong in Yun- nan, Chuxiong in Yunnan, Bijie in Guizhou, Liuyang in Hunan, Suiyang in Guizhou, Kaiyuan in Liaoning, Nanxiong in Guangdong) as calibration samples, and 67 aroma components as indices. And the Fisher discriminant functions were verified using 21 C3F and 19 B2F tobacco leaf samples. [Result] Variation coefficients of the propor- tions were lower than that of contents of most aroma components in middle and upper leaves of the samples, indicating that the proportions were more stable than contents of aroma components. The proportions of benzyl alcohol, solanone, β-dam- ascone, neophytadiene, farnesylacetone A, palmitic acid, thunbergol, methyl linole- nate and cembratriene-diol were all over 1% in both middle and upper leaves, al- though the dominant aroma components of the same aroma type varied between middle and upper leaves. Moreover, 11, 18, 7 and 11 aroma components were re- spectively introduced into the Fisher discriminant functions established based on the contents and proportions of middle and upper flue-cured tobacco leaves, which ex- hibited accuracy rates of 91.7%, 100%, 91.7% and 91.7% in the judgments of other tobacco leaf samples. The results revealed that the components those determined aroma types in middle leaves were obviously more than in upper leaves. In middle leaves, the accuracy rates of aroma type judgment could be improved by using the proportions rather than the contents of aroma components as indices. However, the functions based on the proportions and the contents of aroma components in upper leaves gave close accuracy rates. [Conclusion] The results of the study will provide references for identifying aroma types of flue-cured tobacco leaves in future work. 展开更多
关键词 Flue-cured tobacco leaves Middle leaves Upper leaves Aroma com- ponents Content PROPORTION Aroma type Discriminant analysis
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Dynamic Change Laws of Chlorophyll Fluorescence Parameters in Different Parts of Leaves of Ginkgo biloba
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作者 王秀珍 段爱国 +1 位作者 保尔江 张建国 《Agricultural Science & Technology》 CAS 2011年第4期530-532,536,共4页
[Objective] The aim was to explore the dynamic change laws of chlorophyll fluorescence parameters in different parts of leaves of Ginkgo biloba.[Method] The G.biloba cultivated in North China was used as materials in ... [Objective] The aim was to explore the dynamic change laws of chlorophyll fluorescence parameters in different parts of leaves of Ginkgo biloba.[Method] The G.biloba cultivated in North China was used as materials in this study to explore the law of daily change and ten-day change of the chlorophyll fluorescence parameters of leaves in different parts of leaves.[Result] The daily change of Fm(maximal fluorescence),Fv(variable fluorescence),Fv/Fm,Fm/Fo(electron transfer rate),Fv/Fo(potential activity of PSⅡ)in leaves of G.biloba obviously presented a descending-ascending trend,the lowest value was at 12:00 and the NPQ(non-photochemical quenching)of sunny leaves arrived at the maximum at noon.The values of Fm,Fv,Fv/Fm,Fm/Fo,Fv/Fo in shade leaves of G.biloba were obviously higher than those in sunny leaves,but the peak value of NPQ of shade leaves presented earlier and higher,suggesting that the shade leaves might have more sensitive hot dissipation mechanism.Comparing to sunny leaves,shade leaves had the higher PSⅡ potential activity and inner light energy translation efficiency.[Conclusion] This study had provided theoretical basis for the protection of G.biloba resources. 展开更多
关键词 Ginkgo biloba Chlorophyll fluorescence Sunny leaves Shade leaves Daily change Ten-day change
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Antifungal Activity of Extracts from Clerodendrum Bungei Leaves against Two Species of Phytopathogens 被引量:18
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作者 尹礼国 林娜 +2 位作者 魏琴 张超 周黎军 《Agricultural Science & Technology》 CAS 2008年第1期143-145,共3页
The test was undertaken to reveal the antifungal activity of extracts from Clerodendrum bungei leaves against Pestalotia and Rhizoctonia solani, the results showed that optimal condition for best antifungal activity o... The test was undertaken to reveal the antifungal activity of extracts from Clerodendrum bungei leaves against Pestalotia and Rhizoctonia solani, the results showed that optimal condition for best antifungal activity of extracts against pestalotia and Rhizoctonia solani are as follows: material-liquid ratio of 1:6,75% ethanol as extracting solvent, reflux at 90℃ for 1.5 h. The substances with good dissolubility in ethanol and water solution such as organic acid, bioflavonoid and alkaloid are main antifungal bioactive substances in Clerodendrun bungei. 展开更多
关键词 Clerodendrum bungei leaves Pestalotia funereal Rhizoctonia solani Antifungal activity
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Extraction Storage and Qualitative Analysis of Free Radicals Scavenging Substances from Sweet Potato Leaves 被引量:9
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作者 王友升 董银卯 +1 位作者 宋彦 黑维俭 《Agricultural Science & Technology》 CAS 2008年第2期1-5,9,共6页
[ Objective ] The research aimed to provide reference for the application of extracts from sweet potato leaves in anti-aging cosmetics. [ Method ] The extraction and storage conditions for free radicals scavenging sub... [ Objective ] The research aimed to provide reference for the application of extracts from sweet potato leaves in anti-aging cosmetics. [ Method ] The extraction and storage conditions for free radicals scavenging substances from sweet potato leaves were optimized by orthogonal test and the bioactive components in extracts were investigated by correlation analysis. [ Result] Sweet potato leaves contain the bioactive substances scavenging DPPH free radical and hydroxyl free radical. Extracting solvent species is the most important factor that influencing extraction yield. The optimal extraction and storage conditions are as following: water as solvent, pH 8.0 of extracting liquid, storage at 25 ℃. There is a good positive linear relationship between the content of total phenols in sweet potato leaves and corresponding scavenging rates against both the DPPH free radical and hydroxyl free radical. For the content of total flavones in sweet potato leaves, just a correlation with scavenging rate against hydroxyl free radical shown in test. [ Conclusion] The phenols in ex- tracts could effectively scavenge both the DPPH free radical and hydroxyl free radical, whereas the flavones in extracts can only function on the hydroxyl free radical. 展开更多
关键词 Sweet potato leaves Free radicals scavenging Total phenol Total flavones
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Regulation of Nitric Oxide on the Aging Process of Wheat Leaves 被引量:7
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作者 屠洁 沈文飚 徐朗莱 《Acta Botanica Sinica》 CSCD 2003年第9期1055-1062,共8页
When the first fully expanded leaf of wheat ( Triticum aestivum L.) seedlings with two leaves were treated with different concentrations (0.05, 0.10, 0.20 and 0.50 mmol/L) of nitric oxide donor, sodium nitroprusside (... When the first fully expanded leaf of wheat ( Triticum aestivum L.) seedlings with two leaves were treated with different concentrations (0.05, 0.10, 0.20 and 0.50 mmol/L) of nitric oxide donor, sodium nitroprusside (SNP), the contents of hydrogen peroxide (H2O2) and malondialdehyde (MDA) were reduced by the lower concentrations (0.05, 0.10 and 0.20 mmol/L), but enhanced by the higher concentration of SNP (0.50 mmol/L). The protective effect of 0.10 mmol/L SNP was the most obvious. Furthermore, the treatment with 0.10 mmol/L SNP on the above seedlings until the fourth leaves were fully expanded attenuated the accumulation of H2O2, superoxide anion radical (O-2(-)) and MDA, also counteracted the degradation of chlorophyll and soluble proteins, especally Rubisco, both leading to the effective delay of aging process in wheat leaves. The effects of different SNP concentrations (0.05, 0.10, 0.20, 0.50, 1.00 and 5.00 mmol/L) also displayed a dual role in an aging experiment of chloroplasts in vitro, one of which, 0.2 mmol/L SNP treatment, protected the membrane structure and attenuated the degradation of Rubisco effectively. Based on the present results, it was inferred that lower concentrations of nitric oxide (NO) might play a role in delaying aging process in wheat leaves, i.e., might attribute to decrease the level of reactive oxygen species (ROS) and the alleviation of further oxidative damage caused by ROS. 展开更多
关键词 nitric oxide (NO) wheat leaves AGING reactive oxygen species
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Homogenate extraction technology of camptothecine and hydroxycamptothecin from Camptotheca acuminata leaves 被引量:2
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作者 史伟国 祖元刚 +1 位作者 赵春建 杨磊 《Journal of Forestry Research》 SCIE CAS CSCD 2009年第2期168-170,I0004,共4页
Camptothecine (CPT) and hydroxycamptothecin (HCPT), two kinds of anti-cancer alkaloids, were extracted from Camptotheca acuminata leaves using homogenate extraction technology under different conditions such as th... Camptothecine (CPT) and hydroxycamptothecin (HCPT), two kinds of anti-cancer alkaloids, were extracted from Camptotheca acuminata leaves using homogenate extraction technology under different conditions such as the ratio of material to liquid, ethanol concentration, and homogenate time. The optimum technology parameters for homogenate extraction of CPT and HCPT from C acuminata leaves were determined as homogenate time at 8 rain, ethanol concentration at 55% and the ratio of material to liquid at 1:15 (g:mL). By using the optimized parameters, we obtained 0.639‰ extraction rate for CPT and 0.437‰ for HCPT. The extraction yields of CPT and HCPT extracted by homogenating technology were higher than those by other extractive methods, such as ultrasonic, reflux, shaking in water bath. It is concluded that the homogenate extraction technology was an efficient method for extracting CPT and HCPT from C acuminata leaves, with characteristics of less extraction time and high yield. 展开更多
关键词 HOMOGENATE Camptotheca acuminata leaves camptothecine HYDROXYCAMPTOTHECIN
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Effects of Different Light Qualities on Activity and Gene Expression of Caspase-like Proteases in Tobacco Leaves 被引量:3
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作者 赵娟 柯学 +2 位作者 徐超华 李军营 龚明 《Agricultural Science & Technology》 CAS 2012年第2期276-279,338,共5页
[Objective] The study aimed to investigate the activity and gene expression of caspase-like proteases in tobacco leaves growing under different light qualities. [Method] By covering tobacco plants with white, red, yel... [Objective] The study aimed to investigate the activity and gene expression of caspase-like proteases in tobacco leaves growing under different light qualities. [Method] By covering tobacco plants with white, red, yellow, blue and purple films to obtain different light quality, the changes of chlorophyll content, activity and gene expression of caspase-like proteases in the tobacco leaves were studied. [Results] Compared with treatments of white, red and yellow film, blue and purple films delayed the decrease of chlorophyll content and senescence of tobacco leaves at the late growth stage, and relatively lowered the activity and gene expression of caspase-like proteases during growth, development and senescence periods. [Conclusion] Different light qualities exhibited various effects on the growth, development and senescence of tobacco leaves, possibly by affecting the activity and gene expression of caspase-like proteases to some extent. 展开更多
关键词 Light quality Tobacco leaves Growth and development Caspase-like proteases
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Hypoglycemic Effect of Forsythia suspensa Leaves on Diabetic Mice 被引量:10
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作者 刘静 杨建雄 《Agricultural Science & Technology》 CAS 2013年第1期98-99,175,共3页
[Objective] This study aimed to investigate the hypoglycemic effect of Forsythia suspensa leaves in diabetic mice. [Method] The model of hyperglycemia mice were obtained by injecting streptozotocin intraperitoneally t... [Objective] This study aimed to investigate the hypoglycemic effect of Forsythia suspensa leaves in diabetic mice. [Method] The model of hyperglycemia mice were obtained by injecting streptozotocin intraperitoneally to study the effect of F. suspensa leaves on lowering blood sugar of hyperglycemia mice and normal ani- mals. [Result] F. suspensa leaves could antagonize the streptozotocin-reducing mice hyperglycemia and significantly reduce the fasting blood glucose level of diabetic mice. [Coaclusion] F. suspensa leaves exhibits a good therapeutic effect on diabetic mice and has a good development prospect. 展开更多
关键词 Forsythia suspensa leaves Lower blood sugar DIABETES
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Protective Effects of Aqueous Extract of Eucommia ulmiodes Oliver Leaves on Liver Mitochondria 被引量:7
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作者 刘静 杨建雄 《Agricultural Science & Technology》 CAS 2013年第4期627-629,共3页
[Objective] This study aimed to investigate the protective effects of aqueous extract of Eucommia ulmiodes Oliver leaves (AEO) on liver mitochondrial injury induced by free radicals. [Method] MDA content was determi... [Objective] This study aimed to investigate the protective effects of aqueous extract of Eucommia ulmiodes Oliver leaves (AEO) on liver mitochondrial injury induced by free radicals. [Method] MDA content was determined by thiobarbituric acid colorimetric method; mitochondrial swelling degree was determined by spectrophotometry; the superoxide anion radical scavenging ability was determined using reduced coenzyme I-tetrazolium-phenazine methosulfate as the superoxide anion generation system. Mice were hypodermically injected in the back and neck with D- galactose, after 50 d, the effects of AEO on the activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and anti-hydroxyl radicals in mouse liver were determined using kits. [Result] AEO can efficiently reduce the liver injury and inhibit mitochondrial swelling induced by Fe2+-L-Cys, which can also scavenge superoxide anion and improve the activities of antioxidant enzymes. [Conclusion] This study provided scientific basis for the development and application of AEO resources. 展开更多
关键词 Eucommia ulmiodes Oliver leaves Antioxidase MITOCHONDRIA
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Effects of Ratio of Row Spacing to Intrarow Spacing on Yield and Top Three Leaves of Super High-yielding Early and Late Rice 被引量:2
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作者 林洪鑫 彭春瑞 +5 位作者 雷享亮 袁展汽 肖运萍 刘仁根 胡启锋 张结刚 《Agricultural Science & Technology》 CAS 2014年第1期52-56,101,共6页
Using a split plot design, super high-yielding early rice &quot;Zhongjiazao 17&quot;and &quot;Ganxin 203&quot; and super high-yielding late rice &quot;Ganxin 688&quot; and &quot;Wufengy-ouT025&quot; were taken... Using a split plot design, super high-yielding early rice &quot;Zhongjiazao 17&quot;and &quot;Ganxin 203&quot; and super high-yielding late rice &quot;Ganxin 688&quot; and &quot;Wufengy-ouT025&quot; were taken as materials with planting density the same at 312 000 hil s/hm2, to explore the effects of RS/IS (Ratio of row spacing to intrarow row spacing) on yield, top three leaves morphological features and its relationship of them in 2011 and 2012. The results showed that, whether early or late rice, biomass, accumula-tion and apparent utilizing rate of nitrogen were lower in RS/IS5.0 (40.0 cm &#215;8.0 cm) treatment, but yield of rice was higher in RS/IS2.0 (25.0 cm &#215;12.8 cm) treatment;grain numbers per spike of rice was more in RS/IS2.8 (30.0 cm&#215;10.7 cm) treatment, and thousand-grain weight of rice was higher in RS/IS1.3 (20.0 cm&#215;16.0 cm) treat-ment. For 4 varieties of early or late rice aforementioned, basal angle, opening an-gle and leaf area of 2nd leaf from top were larger in RS/IS5.0 treatment, and basal angle and opening angle were smal er in RS/IS2.0 treatment and leaf area smal er in RS/IS1.3 treatment. 展开更多
关键词 Super high-yielding early and late rice Ratio of row spacing to intrarowspacing Top three leaves Leaf morphology
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Effects of Different Transplanting and Harvest Dates on Yield and Quality of Flue-cured Tobacco Leaves 被引量:1
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作者 彭世逞 吴昊 +3 位作者 官宇 潘兴兵 罗蔓 董华芳 《Agricultural Science & Technology》 CAS 2016年第5期1255-1260,共6页
In this study,the effects of nine different combinations of transplanting and harvest dates on yield and quality of flue-cured tobacco leaves were investigated.The results showed that different combinations of transpl... In this study,the effects of nine different combinations of transplanting and harvest dates on yield and quality of flue-cured tobacco leaves were investigated.The results showed that different combinations of transplanting and harvest dates had few effects on growth period and agronomic characters of tobacco plants but exerted remarkable effects on economic characters and chemical composition of flue-cured tobacco leaves.With the postponing of transplanting stage,output value of flue-cured tobacco leaves increased.Output value of flue-cured tobacco leaves in C1treatment(normal harvest) was higher than that in C2(harvest 7 d later) and C3(harvest 14 d later) treatments.Different combinations of transplanting and harvest dates had significant effects on chemical composition of flue-cured tobacco leaves,which exhibited no obvious law.Overall,flue-cured tobacco leaves in T3C1treatment(transplanting 14 d earlier,normal harvest) displayed excellent performance compared with other treatments. 展开更多
关键词 Flue-cured tobacco leaves Transplanting date Harvest date YIELD QUALITY
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Study of the Short-time Eco-physiological Response of Plant Leaves to Dust 被引量:20
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作者 陈雄文 《Acta Botanica Sinica》 CSCD 2001年第10期1058-1064,共7页
The short-time eco-physiological response to dust was measured for the leaves of 22 local popular plant species including roadside trees, fruit trees, forest trees and crop species in Beijing. The dust did affect the ... The short-time eco-physiological response to dust was measured for the leaves of 22 local popular plant species including roadside trees, fruit trees, forest trees and crop species in Beijing. The dust did affect the eco-physiology of leaves of these species. After being covered by dust the instant net photosynthetic rates of most plant species changed insignificantly, but it decreased by more than 35% for 5 species, and it increased by-more than 57% for Ginkgo biloba L. The respiration rates of 12 plant species increased significantly, but it decreased significantly for Malus pumila Mill. (M. communis D C.) and Cotinus coggygria (L.) Scop., and it changed insignificantly for the other 8 species. The transpiration rates of 5 plant species increased significantly, however, they decreased for 9 species, and changed insignificantly for the other 8 species. Platanus occidentalis L. had highest dust carrying capacity. After 2 h the physiological indices did not change significantly for Diospyros kaki L. f., G. biloba and Populus tomentosa Carr. The implications of the research are that Ulmus laevis Pall., M. pumila (M. communis), D. kaki and G. biloba are suitable for amelioration of dust storm damage and increase in local economical development near the sources of dust storms in western China. And in the cities, such as Beijing and other dust areas, the plants have high dust-carrying capacity can be planted for air cleaning. 展开更多
关键词 leaves eco-physiological response DUST
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Effects of Magnetic Stress on the Delayed Luminescence of Mung Bean Leaves 被引量:2
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作者 石朝晖 《Agricultural Science & Technology》 CAS 2010年第2期5-7,共3页
[Objective] The research aimed to study the effects of magnetic stress on the delayed luminescence of mung bean leaves.[Method]With mung bean leaves as the experimental materials,the delayed luminescence curve of mung... [Objective] The research aimed to study the effects of magnetic stress on the delayed luminescence of mung bean leaves.[Method]With mung bean leaves as the experimental materials,the delayed luminescence curve of mung bean leaves under the same magnetic field intensity at different processing time was measured by using BPCL-type weak luminescence measuring instrument.[Result] The absorption of the magnetic field stimulation within the leaves had its own rules.A certain magnetic field intensity and a certain... 展开更多
关键词 Mung bean leaves Magnetic stress Delayed luminescence
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Nutrients of green and senesced leaves of a Robinia pseudoacacia plantation along a latitudinal gradient on the Loess Plateau,China 被引量:2
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作者 Quanchao Zeng Yang Liu +3 位作者 Jiajia Yang Yanan Chen Lusha Ma Shaoshan An 《Journal of Forestry Research》 SCIE CAS CSCD 2021年第6期2499-2506,共8页
Plantations have been widely established to improve ecosystem services and functioning.Black locust,Robinia pseudoacacia L.is a common,widely planted species to control soil erosion on the Loess Plateau.Previous studi... Plantations have been widely established to improve ecosystem services and functioning.Black locust,Robinia pseudoacacia L.is a common,widely planted species to control soil erosion on the Loess Plateau.Previous studies have focused on economic values but the interactions between soil and plant carbon(C),nitrogen(N)and phosphorus(P)remain unknown.Investigating variations of soil,green and senesced leaf C,N and P levels in R.pseudoacacia along a latitudinal gradient is useful to understanding its ecological functions.The results show that soil C,N and senesced leaf N and P significantly decreased with an increase in latitude,but there were no significant changes in the senesced leaf C and soil P.The resorption efficiency of N was related with latitude and soil N levels,and the relation between green leaf N and soil N was significant.These relations suggest that soil N was the key in affecting green leaf N levels.At higher latitudes,senesced leaves had lower N levels associated with higher N resorption efficiency to maintain a stable N content in green leaves.With a decrease of soil N,R.pseudoacacia can enhance N resorption efficiency to meet the demand of growth.Thus,it is an important species for reforestation,especially in nutrient-poor environments. 展开更多
关键词 Green leaves Senesced leaves Resorption efficiency Robinia pseudoacacia Loess plateau Vegetation restoration
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Judgment of Aroma Types of Middle and Upper Flue-cured Tobacco Leaves Based on Proportions of Aroma Components 被引量:3
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作者 詹军 周芳芳 +5 位作者 包崇彦 毛春堂 邓国宾 王伟 杨俊 张晓龙 《Agricultural Science & Technology》 CAS 2013年第4期612-619,共8页
[Objective] This study aimed to establish mathematical models for judging the aroma types of flue-cured tobacco leaves from the upper and middle parts of plants. [Method] A total of 128 samples (63 C3F and 65 B2F) f... [Objective] This study aimed to establish mathematical models for judging the aroma types of flue-cured tobacco leaves from the upper and middle parts of plants. [Method] A total of 128 samples (63 C3F and 65 B2F) from 11 main tobac- co production provinces of China were selected as materials. Stepwise discriminant analysis was applied to samples with different aroma types and discriminant function was expressed with the proportions of 67 aroma components in total aroma con- stituents as the index. [Result] The ratio of most aroma components in clear and full aroma tobacco leaves was higher than that in middle aroma leaves. The ratios of 51, 43 and 40 aroma components of clear, middle and full aroma tobaccos were higher in upper leaves than that in middle leaves. Aroma components dominated certain aroma types differed between middle and upper leaves. The proportions of 18 and 11 aroma components in upper and middle leaves were led in the stepwise discriminant function respectively. Self-validation and cross-validation methods were applied to evaluate the original samples, and the accuracy rates reached 100% and 98.6% on middle leaves, 96.37% and 94.4% on upper leaves. The accuracy rates on some other samples reached 100% on middle leaves and 91.7% on upper leaves predicted with the model. [Conclusion] The ratio of aroma components as discriminant index could improve discriminant accuracy significantly in the middle and upper leaves. It could be used to analyze aroma types objectively, accurately and quickly. 展开更多
关键词 Flue-cured tobacco Aroma components Middle leaves Upper leaves Ratio Aroma types Discriminant analysis
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Effects of Exogenous Amylases and Metal Ions on the Amylase Specific Activities and Starch Degradation of the Upper Leaves of ‘KRK_(26)' during Flue-curing 被引量:1
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作者 赵昶灵 崔国民 孟凡来 《Agricultural Science & Technology》 CAS 2014年第10期1676-1683,共8页
Objective] The aim of this study was to investigate the effects of exoge-nous amylases and Ca2+, Mn2+ and K+ on the amylase specific activities and starch degradation of the upper leaves of 'KRK26' planted in Yun... Objective] The aim of this study was to investigate the effects of exoge-nous amylases and Ca2+, Mn2+ and K+ on the amylase specific activities and starch degradation of the upper leaves of 'KRK26' planted in Yunnan Province during flue-curing. [Method] The amylase specific activities and starch degradation of the leaves were determined by using spectrophotometry. [Result] The 8 U/g exogenous α-amy-lase could improve the specific activity of the leaf α-amylase at yel owing and color-fixing stages, but could not at stem-drying stage, and similarly, the 80 U/g exoge-nous β-amylase could improved the specific activity of the leaf β-amylase at the yel owing stage and the early period of color-fixing stage. The leaf starch could be enhanced to degrade by the exogenous α- or β-amylases and the enhancing effect of the former was stronger than that of the later. 1.50 mg/ml Ca2+ improved the specific activity of the leaf (α+β)-amylase mainly due to its enhancing effect on the leaf α-amylase, and increased the starch degradation. 4 mmol/L Mn2+ inhibited the leaf α-amylase from yel owing to the early period of color-fixing and the β- and (α+β)-amylases from the yel owing to the later period of color-fixing, but enhanced the leafα-amylase from the later period of color-fixing to the later period of stem-drying and the β- and (α+β)-amylases at the later period of stem-drying. Meanwhile, Mn2+ ham-pered the starch degradation during yel owing, but promoted it from the early period of color-fixing to stem-drying. 1 mg/ml K+ enhanced the leaf α-, β- and (α+β)-amy-lases during the yel owing stage, but lowered them from the early period of color-fix-ing to the later period of stem-drying, and always inhibited the leaf starch degrada-tion. [Conclusion] The exogenous α-, β- amylases and Ca2+ of suitable concentra-tions could be used to treat the tobacco leaves before flue-curing to improve the leaf starch degradation during the curing. 展开更多
关键词 Exogenous amylases and metal ions Amylase specific activity Starchdegradation Upper leaves of flue-cured tobacco variety 'KRK26' Flue-curing
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Electrophoresis Analysis on the Protein Expression in Heteromorphic Leaves of Populus euphratica Oliv. 被引量:1
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作者 岳宁 郑彩霞 Cai-xia 《Agricultural Science & Technology》 CAS 2010年第5期41-45,共5页
[Objective] This study was to elucidate the cellular and molecular mechanism of the development of heteromorphic leaves of Populus euphratica Oliv. [Method] By employing SDS-PAGE and 2-demensional electrophoresis (2-D... [Objective] This study was to elucidate the cellular and molecular mechanism of the development of heteromorphic leaves of Populus euphratica Oliv. [Method] By employing SDS-PAGE and 2-demensional electrophoresis (2-DE) techniques,proteins in various heteromorphic leaves from the same adult tree of P. euphratica were isolated and separated to the electrophoresis technique suitable for the separation and analysis of proteins in leaves of P. euphratica tree. [Results] There were significant differences in the expressions of proteins in various heteromorphic leaves of P. euphratica tree. SDS-PAGE pattern showed that bands of proteins with molecular weight of 57.2,13.2,30.2,23.9 and 33.3 kDa were remarkably different. 2-D electrophoresis pattern presented that proteins in leaves of P. euphratica tree mainly belong to acidic proteins distributed at pH value of 5.0-6.5 and with molecular weight of 20-40 kDa; totally 73 different protein spots were observed,of which 51 were up expressed and other 22 were down expressed in the serrated ovate leaves. [Conclusion] Based on these results,we speculate that regulated gene expression in leaves of P. euphratica tree results in the generation of different shapes of leaves,in order to adapt to the surroundings better. 展开更多
关键词 Populus euphratica Oilv. Heteromorphic leaves SDS-PAGE 2-demensional electrophoresis
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Effects of Loading Methods on the Color,Phenolic and Antioxidant Properties of Cured Tobacco Leaves
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作者 傅茂润 赵双 +12 位作者 侯连涛 曲清莉 代红飞 董梅 苏建东 刘广玉 杨举田 王梅勋 田雷 杨永花 谭效磊 徐硕 宗浩 《Agricultural Science & Technology》 CAS 2014年第7期1196-1199,共4页
[Objective] To investigate the effects of different loading methods on tobacco leaf quality.[Method] With tobacco comb,tobacco clamp,and tobacco basket,color,phenolic compounds and their antioxidant capacity of flue-c... [Objective] To investigate the effects of different loading methods on tobacco leaf quality.[Method] With tobacco comb,tobacco clamp,and tobacco basket,color,phenolic compounds and their antioxidant capacity of flue-cured tobacco leaves were studied.[Result] The results showed that L*,a* and b* values of tobacco leaves packaged by tobacco clamp and comb were higher than those of tobacco basket and no significant differences were found beween values of a* and b*,however,between L* and h values,remarkable differences existed among three loading methods.Total phenolic content and chlorogenic acid content of tobacco leaves loaded by tobacco comb kept the highest,followed by smoke clamp and tobacco basket (P<0.05).On the other hand,rutin content showed little differences among treatments.The order of the antioxidant properties,such as DPPH free radical scavenging activity and reducing powder,of tobacco leaves by different loading methods was tobacco comb > tobacco clamp > loose basket and a positive relationship was found of antioxiang property with total phenolic content and chlorogenic acid content.[Conclusion] In view of tobacco leaves quality and antioxidant property,loading method with tobacco comb proved to be a better choice. 展开更多
关键词 PHENOLIC Color parameters Antioxidant capacity loading method Tobacco leaves
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Anti-insect Bioactivity of the Extracts from Cichorium intybus L. Leaves
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作者 孙娈姿 杜金鸿 +2 位作者 呼天明 王佺珍 崔健 《Agricultural Science & Technology》 CAS 2010年第6期99-102,共4页
In order to develop a new plant-source insecticide,some active components from Cichorium intybus L.were extracted with mineral ether,ethyl ether,ethyl acetate,respectively.It were testified the effects of the componen... In order to develop a new plant-source insecticide,some active components from Cichorium intybus L.were extracted with mineral ether,ethyl ether,ethyl acetate,respectively.It were testified the effects of the components on the development of Mythimna separate Walker and anti-feeding by feeding and weighting method.The results showed that the body weight of the larvae fed by the extracts with organic solvents was significantly lower than the control;the body weight of the larvae fed by the extracts with organic solvents was significantly different in different solvents in 3-5 days.The corrected mortality of the ethyl acetate treatment was the highest(52.05%),and the development period of the larvae treated by ethyl acetate was about 4-10 days longer than the control and the corresponding pupating rate was the lowest(43.30%).Therefore,the effect of ethyl acetate extract was most significant.Moreover,the pupa weight of the treatments was little more than the control.The extracts from Cichorium intybus L.leaves had highest bioactivity mainly in anti-feeding activity on Mythimna separate Walker. 展开更多
关键词 Cichorium intybus L.leaves EXTRACTIONS Anti-insect bioactivity DEVELOPMENT
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