Consistent with previous research, results showed men get more paragraphs and photography coverage. Interestingly, women's factual information is always associated with relevant men report, including P.E relevant ...Consistent with previous research, results showed men get more paragraphs and photography coverage. Interestingly, women's factual information is always associated with relevant men report, including P.E relevant with personal information.展开更多
The regional policy in the innovation development of private P.E economy plays better role in management according to law,guidance and escort;increase the macro quality of main body of private P.E entrepreneurs and th...The regional policy in the innovation development of private P.E economy plays better role in management according to law,guidance and escort;increase the macro quality of main body of private P.E entrepreneurs and the overall staff quality,develop P.E vocational P.E to provide P.E talents for private P.E economy.展开更多
The portal is characterized with large amount of information, high stability and interaction, while "Online Journal of Physical P.E" is to publicize the academic pure value, spread the achievement influence ...The portal is characterized with large amount of information, high stability and interaction, while "Online Journal of Physical P.E" is to publicize the academic pure value, spread the achievement influence in daily life, and advocate an academic atmosphere of utilitarianism with a slogan of "article issued online can be published in journal with the recommendation of experts" and practical action. It is the first academic journal under network operation.展开更多
Partial substitution of chemical fertilizers by organic amendments is adopted widely for promoting the availability of soil phosphorus(P)in agricultural production.However,few studies have comprehensively evaluated th...Partial substitution of chemical fertilizers by organic amendments is adopted widely for promoting the availability of soil phosphorus(P)in agricultural production.However,few studies have comprehensively evaluated the effects of longterm organic substitution on soil P availability and microbial activity in greenhouse vegetable fields.A 10-year(2009–2019)field experiment was carried out to investigate the impacts of organic fertilizer substitution on soil P pools,phosphatase activities and the microbial community,and identify factors that regulate these soil P transformation characteristics.Four treatments included 100%chemical N fertilizer(4 CN),50%substitution of chemical N by manure(2 CN+2 MN),straw(2 CN+2 SN),and combined manure with straw(2 CN+1 MN+1 SN).Compared with the 4 CN treatment,organic substitution treatments increased celery and tomato yields by 6.9-13.8%and 8.6-18.1%,respectively,with the highest yields being in the 2 CN+1 MN+1 SN treatment.After 10 years of fertilization,organic substitution treatments reduced total P and inorganic P accumulation,increased the concentrations of available P,organic P,and microbial biomass P,and promoted phosphatase activities(alkaline and acid phosphomonoesterase,phosphodiesterase,and phytase)and microbial growth in comparison with the 4 CN treatment.Further,organic substitution treatments significantly increased soil C/P,and the partial least squares path model(PLS-PM)revealed that the soil C/P ratio directly and significantly affected phosphatase activities and the microbial biomass and positively influenced soil P pools and vegetable yield.Partial least squares(PLS)regression demonstrated that arbuscular mycorrhizal fungi positively affected phosphatase activities.Our results suggest that organic fertilizer substitution can promote soil P transformation and availability.Combining manure with straw was more effective than applying these materials separately for developing sustainable P management practices.展开更多
To assess the effects of savanna afforestation on soil phosphorus （P） transformations in eastern Horqin Sandy Land, China, P fractions and phosphomonoesterase activities were examined in two soil horizons （0-5 cm a...To assess the effects of savanna afforestation on soil phosphorus （P） transformations in eastern Horqin Sandy Land, China, P fractions and phosphomonoesterase activities were examined in two soil horizons （0-5 cm and 5-20 cm） under a savanna and an adjacent 30-year-old Mongolian pine （Pinus sylvestris L. vat. mongolica Litv.） plantation on a P-deficient semi arid sandy soil. The results showed that all soil P fractions and phosphomonoestcrase activities decreased with soil depth at both sites except that labile organic P under the plantation was constant with soil depth, In contrast to savanna, soils trader Mongolian pine plantation had lower phosphomonoesterase activities and concentrations of all P fractions （with an exception of Al-P）, lower proportions of organic P and Ca-P in total P, and higher proportions of labile P, Al-P and Fe-P in total P. These results suggested that P transformations mainly occurred in surface soils, and P recycled through litterfall was the most important source of plant available P. Mongolian pine afforestation enhanced the bioavailability of both organic P and Ca-P. simultaneously reduced soil P pools. indicating that protection of forest floor and P fertilization are necessary to maintain the sustainable functioning of Mongolian pine plantations.展开更多
In order to discover novel compounds with high-activity to control aphid,a series of novel（E）-β-farnesene analogues containing 1,2,3-thiadiazole were designed and synthesized,and their structures were confirmed by ...In order to discover novel compounds with high-activity to control aphid,a series of novel（E）-β-farnesene analogues containing 1,2,3-thiadiazole were designed and synthesized,and their structures were confirmed by IR,^1H NMR,^13C NMR,and HRMS（ESI）.The stability of representative compounds was studied by HPLC and -1H NMR techniques.Repellent activity results indicated that compounds 8h and 8j displayed 60.3%and 62.0%repellent rates,respectively.The aphicidal bioassay results showed that most analogues exhibited considerable aphicidal activity against Myzus persicae.Especially,analogues 81,8s and 8t exhibited high activity with LC50 values of 33.4 μg/mL,50.2 μg/mL and 61.8 μg/mL,respectively,which were higher than the lead compound（E）-β-farnesene,but lower than commercial insecticide pymetrozine with a LC50 of 7.1 μg/mL展开更多
[ Objective ] The paper was to screen the better extraction method for herbicidal active substances of Eupatorium adenophorum. [ Method ] Three com- mon extraction methods, Soxhlet extraction, ultrasonic extraction an...[ Objective ] The paper was to screen the better extraction method for herbicidal active substances of Eupatorium adenophorum. [ Method ] Three com- mon extraction methods, Soxhlet extraction, ultrasonic extraction and conventional extraction method, were used to prepare E. adenophorum extracts, and the herblcidal activity of E. adenophorum extracts extracted by 3 methods was studied by seed germination method. [ Result] The extraction rate of Soxhlet extraction was the highest of （22.54 ± 0.48 ）%, and the herbicidal activities of E. adenophorum extracted by Soxhlet extraction was relatively stronger. [ Conclusion] Soxhlet extraction was the better extraction method for herbicidal active substances of E. adenophorum.展开更多
Background:Whether or not there is targeted pharmacotherapy for dementia,an active and healthy lifestyle that includes physical activity(PA)may be a better option than medication for preventing dementia.We examined th...Background:Whether or not there is targeted pharmacotherapy for dementia,an active and healthy lifestyle that includes physical activity(PA)may be a better option than medication for preventing dementia.We examined the association between leisure-time sedentary behavior(SB)and the risk of dementia incidence and mortality.We further quantified the effect on dementia risk of replacing sedentary time with an equal amount of time spent on different physical activities.Methods:In the UK Biobank,484,169 participants(mean age=56.5 years;45.2%men)free of dementia were followed from baseline(2006-2010)through July 30,2021.A standard questionnaire measured individual leisure-time SB(watching TV,computer use,and driving)and PA(walking for pleasure,light and heavy do-it-yourself activity,strenuous sports,and other exercise)frequency and duration in the 4 weeks prior to evaluation.Apolipoprotein E(APOE)genotype data were available for a subset of 397,519(82.1%)individuals.A Cox proportional hazard model and an isotemporal substitution model were used in this study.Results:During a median 12.4 years of follow-up,6904 all-cause dementia cases and 2115 deaths from dementia were recorded.In comparison to participants with leisure-time SB<5 h/day,the hazard ratio((HR),95%confidence interval(95%CI))of dementia incidence was 1.07(1.02-1.13)for 5-8 h/day and 1.25(1.13-1.38)for>8 h/day,and the HR of dementia mortality was 1.35(1.12-1.61)for>8 h/day.A 1 standard deviation increment of sedentary time(2.33 h/day)was strongly associated with a higher incidence of dementia and mortality(HR=1.06,95%CI:1.03-1.08 and HR=1.07,95%CI:1.03-1.12,respectively).The association between sedentary time and the risk of developing dementia was more profound in subjects<60 years than in those>60 years(HR=1.26,95%CI:1.00-1.58 vs.HR=1.21,95%CI:1.08-1.35 in>8 h/day,p for interaction=0.013).Replacing 30 min/day of leisure sedentary time with an equal time spent in total PA was associated with a6%decreased risk and 9%decreased mortality from dementia,with exercise(e.g.,swimming,cycling,aerobics,bowling)showing the strongest benefit(HR=0.82,95%CI:0.78-0.86 and HR=0.79,95%CI:0.72-0.86).Compared with APOEε4 noncarriers,APOEε4 carriers are more likely to see a decrease in Alzheimer’s disease incidence and mortality when PA is substituted for SB.Conclusion:Leisure-time SB was positively associated with the risk of dementia incidence and mortality.Replacing sedentary time with equal time spent doing PA may be associated with a significant reduction in dementia incidence and mortality risk.展开更多
The present study was designed to synthesize derivatives of E-resveratrol and evaluate their cytotoxic activity in vitro.Different functional groups were conjugated with the phenolic hydroxyl group of E-resveratrol,an...The present study was designed to synthesize derivatives of E-resveratrol and evaluate their cytotoxic activity in vitro.Different functional groups were conjugated with the phenolic hydroxyl group of E-resveratrol,and the double bond of E-resveratrol was reduced.The in vitro cytotoxicity of the synthetic derivatives was evaluated against three tumor cell lines(A549,LAC,and He La) using the MTT assay.Twenty-six E-resveratrol derivatives were synthesized and their structures were confirmed by 1H NMR,MS,IR,and elemental analyses.Compounds 1-6,12,15-21,and 23-26 were reported for the first time.Among them,Compounds 1,2,4,5,and 9-11,showed significant cytotoxicity against tumor cells;especially,Compound 1 showed an IC50 value of 4.38 μmol·L-1 in the A549 cells which was 15-fold more active than E-resveratrol;Compound 9 showed an IC50 value of 1.41 μmol·L-1 in the He La cell line which was 90-fold more active than E-resveratrol,and close to adriamycin.The structure–activity relationships were also investigated.Compounds 1,2 and 9-11 may serve as potential lead compounds for the discovery of new anticancer drugs.展开更多
Assays of stress enzymes related to active oxygen species were performed by using an in vitro preparation from the liver of a monkey (Japanese Macaque). Ge-132, an organic germanium compound, viz. poly-trans-[(2-carbo...Assays of stress enzymes related to active oxygen species were performed by using an in vitro preparation from the liver of a monkey (Japanese Macaque). Ge-132, an organic germanium compound, viz. poly-trans-[(2-carboxyethyl) germasesquioxane] [(GeCH2CH2COOH)2O3]n, suppressed the activities of NADH-dependent oxidase and NADPH-dependent oxidase [NAD(P)H-OD] and xanthine oxidase (XOD) as superoxide-forming enzymes, while promoting the activities of superoxide dismutase (SOD) as a superoxide-scavenging enzyme and catalase (CAT) as an enzyme responsible for degradation of hydrogen peroxide (H2O2). The evidence suggests that the levels of active oxygen species such as and H2O2 would be reduced by Ge-132. The possible connection between Ge-132 and activities of stress enzymes is discussed on the basis of these results.展开更多
Alpine tundra ecosystems have specific vegetation and environmental conditions that may affect soil phosphorus （P） composition and phosphatase activities. However, these effects are poody understood. This study used...Alpine tundra ecosystems have specific vegetation and environmental conditions that may affect soil phosphorus （P） composition and phosphatase activities. However, these effects are poody understood. This study used NaOH-EDTA extraction and solution ^31P nuclear magnetic resonance （NMR） spectroscopy to determine soil P composition and phosphatase activities, including acid phosphomonoesterase （AcP）, phosphodiesterase （PD） and inorganic pyrophosphatase （IPP）, in the alpine tundra of the Changbai Mountains at seven different altitudinal gradients （i.e., 2000 m, 2100 m, 2200 m, 2300 m, 2400 m, 2500 m, and 2600 m）. The results show that total P （TP）, organic P （OP）, OP/TP, NaOH-EDTA extracted P and AcP, PD, and IPP activities over the altitude range of 2500-2600 m are significantly lower than those below 2400 m. The dominant extracted form of P is OP （73%0-83%） with a large proportion of monoesters （65%0-72%）, whereas inorganic P is present in lower proportions （17%-27%）. The activity of AcP is significantly positively correlated with the contents of soil OP, total carbon （TC）, total nitrogen （TN）, and TP （P 〈 0.05）, indicating that the AcP is a more sensitive index for responding P nutrient storage than PD and IPP. Soil properties, P composition, and phosphatase activities decrease with increased altitude and soil pH. Our results indicate that the distribution of soil P composition and phosphatase activities along altitude and AcP may play an important role in P hydrolysis as well as have the potential to be an indicator of soil quality.展开更多
Two new zinc（Ⅱ） complexes, [Zn2L2Ch].2[ZnL（CH3OH）Cl2] 1 and [ZnL2（NO3）2] 2, were synthesized by reacting ZnX2.nH2O （X = Cl^-, NO3^-） and a Schiff base ligand 2-[（4-methylphenylimino）methyl]-6-methoxyphenol ...Two new zinc（Ⅱ） complexes, [Zn2L2Ch].2[ZnL（CH3OH）Cl2] 1 and [ZnL2（NO3）2] 2, were synthesized by reacting ZnX2.nH2O （X = Cl^-, NO3^-） and a Schiff base ligand 2-[（4-methylphenylimino）methyl]-6-methoxyphenol （C15HIsNO2, L） which was obtained by the condensation of o-vanillin （2-hydroxy-3-methoxybenzaldehyde） with p-toluidine. Both 1 and 2 were characterized by single-crystal X-ray diffraction technique, elemental analysis, molar conductance, FT-IR, UV-Vis, IH-NMR spectra and thermogravimetrie analysis. The Schiff base ligand and its zinc（Ⅱ） complexes have been tested in vitro to evaluate their antibacterial activity against bacteria, viz., Escherichia Coli, Staphylococcus aureus and Bacillus Subtilis. The results show that these complexes have higher activity than the corresponding free Schiff base ligand against the same bacteria.展开更多
In vitro biological activities including anti-phytopathogenic fungi, antibacterial, antifeedant and herbicidal activities of the extracts from the heartwoods of Mansonia gagei Drumm. were evaluated. The dichlorometha...In vitro biological activities including anti-phytopathogenic fungi, antibacterial, antifeedant and herbicidal activities of the extracts from the heartwoods of Mansonia gagei Drumm. were evaluated. The dichloromethane （DCM） extract displayed antifungal activity against four plant pathogenic fungi （Altemaria porri, Colletotrichum gloeosporioides, Fusarium oxysporum and Phytophthora parasitica） higher than the methanolic （MeOH） extract. The separation of the DCM extract using bioassay guided antifungal activity against P. parasiUca led to the isolation of mansorins A, B, and C, mansonones C, E, G and H. Among isolated compounds, mansonone E displayed the highest antifungal activity against P. parasitica, followed by mansonone C, mansorin B and mansonone G. This potent compound revealed the same minimum inhibitory concentrations （MIC） of 31 μg mL-1 against C. gloeosporioides and P. parasitica, and minimum fungicidal concentration （MFC） of 31 and 125 μg mL-1, respectively. Moreover, mansonone E exhibited highly significant antibacterial activity against both Xanthomonas oryzae pv. oryzae （Xoo） and X. oryzae pv. oryzicola （Xoc） with MIC and minimum bactericidal concentration （MBC） as 7.8 and 〉500μg mL-1, respectively. This compound furthermore could inhibit the feed of Spodoptera litura with 45.9% antifeedant and significantly herbicidal activity reduced the shoot and root growth of Brassica chinensis, Oryza sativa, Mimosa pigra and Echinochlooa crus-galli. Mansonone E has potential as a new natural pesticide for agricultural plant pathogen management.展开更多
文摘Consistent with previous research, results showed men get more paragraphs and photography coverage. Interestingly, women's factual information is always associated with relevant men report, including P.E relevant with personal information.
文摘The regional policy in the innovation development of private P.E economy plays better role in management according to law,guidance and escort;increase the macro quality of main body of private P.E entrepreneurs and the overall staff quality,develop P.E vocational P.E to provide P.E talents for private P.E economy.
文摘The portal is characterized with large amount of information, high stability and interaction, while "Online Journal of Physical P.E" is to publicize the academic pure value, spread the achievement influence in daily life, and advocate an academic atmosphere of utilitarianism with a slogan of "article issued online can be published in journal with the recommendation of experts" and practical action. It is the first academic journal under network operation.
基金supported by the China Agriculture Research System of MOF and MARA(CARS-23-B04)the National Key Research and Development Program of China(2016YFD0201001)。
文摘Partial substitution of chemical fertilizers by organic amendments is adopted widely for promoting the availability of soil phosphorus(P)in agricultural production.However,few studies have comprehensively evaluated the effects of longterm organic substitution on soil P availability and microbial activity in greenhouse vegetable fields.A 10-year(2009–2019)field experiment was carried out to investigate the impacts of organic fertilizer substitution on soil P pools,phosphatase activities and the microbial community,and identify factors that regulate these soil P transformation characteristics.Four treatments included 100%chemical N fertilizer(4 CN),50%substitution of chemical N by manure(2 CN+2 MN),straw(2 CN+2 SN),and combined manure with straw(2 CN+1 MN+1 SN).Compared with the 4 CN treatment,organic substitution treatments increased celery and tomato yields by 6.9-13.8%and 8.6-18.1%,respectively,with the highest yields being in the 2 CN+1 MN+1 SN treatment.After 10 years of fertilization,organic substitution treatments reduced total P and inorganic P accumulation,increased the concentrations of available P,organic P,and microbial biomass P,and promoted phosphatase activities(alkaline and acid phosphomonoesterase,phosphodiesterase,and phytase)and microbial growth in comparison with the 4 CN treatment.Further,organic substitution treatments significantly increased soil C/P,and the partial least squares path model(PLS-PM)revealed that the soil C/P ratio directly and significantly affected phosphatase activities and the microbial biomass and positively influenced soil P pools and vegetable yield.Partial least squares(PLS)regression demonstrated that arbuscular mycorrhizal fungi positively affected phosphatase activities.Our results suggest that organic fertilizer substitution can promote soil P transformation and availability.Combining manure with straw was more effective than applying these materials separately for developing sustainable P management practices.
基金This work was supported by Innovation Research Project of Chinese Academy of Sciences （KZCX3-SW-418）, National Natural Science Foundation of China （30471377） and sustentation project of the Institute of Applied Ecology of Chinese Academy of Sciences （SLYQY0409）.
文摘To assess the effects of savanna afforestation on soil phosphorus （P） transformations in eastern Horqin Sandy Land, China, P fractions and phosphomonoesterase activities were examined in two soil horizons （0-5 cm and 5-20 cm） under a savanna and an adjacent 30-year-old Mongolian pine （Pinus sylvestris L. vat. mongolica Litv.） plantation on a P-deficient semi arid sandy soil. The results showed that all soil P fractions and phosphomonoestcrase activities decreased with soil depth at both sites except that labile organic P under the plantation was constant with soil depth, In contrast to savanna, soils trader Mongolian pine plantation had lower phosphomonoesterase activities and concentrations of all P fractions （with an exception of Al-P）, lower proportions of organic P and Ca-P in total P, and higher proportions of labile P, Al-P and Fe-P in total P. These results suggested that P transformations mainly occurred in surface soils, and P recycled through litterfall was the most important source of plant available P. Mongolian pine afforestation enhanced the bioavailability of both organic P and Ca-P. simultaneously reduced soil P pools. indicating that protection of forest floor and P fertilization are necessary to maintain the sustainable functioning of Mongolian pine plantations.
基金the financial support from the National Natural Science Foundation of China (No. 21132003)
文摘In order to discover novel compounds with high-activity to control aphid,a series of novel（E）-β-farnesene analogues containing 1,2,3-thiadiazole were designed and synthesized,and their structures were confirmed by IR,^1H NMR,^13C NMR,and HRMS（ESI）.The stability of representative compounds was studied by HPLC and -1H NMR techniques.Repellent activity results indicated that compounds 8h and 8j displayed 60.3%and 62.0%repellent rates,respectively.The aphicidal bioassay results showed that most analogues exhibited considerable aphicidal activity against Myzus persicae.Especially,analogues 81,8s and 8t exhibited high activity with LC50 values of 33.4 μg/mL,50.2 μg/mL and 61.8 μg/mL,respectively,which were higher than the lead compound（E）-β-farnesene,but lower than commercial insecticide pymetrozine with a LC50 of 7.1 μg/mL
基金Supported by Youth Fund Project of Yunnan Agricultural University
文摘[ Objective ] The paper was to screen the better extraction method for herbicidal active substances of Eupatorium adenophorum. [ Method ] Three com- mon extraction methods, Soxhlet extraction, ultrasonic extraction and conventional extraction method, were used to prepare E. adenophorum extracts, and the herblcidal activity of E. adenophorum extracts extracted by 3 methods was studied by seed germination method. [ Result] The extraction rate of Soxhlet extraction was the highest of （22.54 ± 0.48 ）%, and the herbicidal activities of E. adenophorum extracted by Soxhlet extraction was relatively stronger. [ Conclusion] Soxhlet extraction was the better extraction method for herbicidal active substances of E. adenophorum.
基金supported by Shanghai Municipal Human Resources and Social Security Bureau(2020074)Clinical Research Plan of SHDC(SHDC2020CR4006)+2 种基金Shanghai Ninth People’s Hospital(YBKA201909)Innovative research team of high-level local universities in Shanghai(SHSMU-ZDCX20212501)Shanghai Municipal Health Commission(2022XD017)。
文摘Background:Whether or not there is targeted pharmacotherapy for dementia,an active and healthy lifestyle that includes physical activity(PA)may be a better option than medication for preventing dementia.We examined the association between leisure-time sedentary behavior(SB)and the risk of dementia incidence and mortality.We further quantified the effect on dementia risk of replacing sedentary time with an equal amount of time spent on different physical activities.Methods:In the UK Biobank,484,169 participants(mean age=56.5 years;45.2%men)free of dementia were followed from baseline(2006-2010)through July 30,2021.A standard questionnaire measured individual leisure-time SB(watching TV,computer use,and driving)and PA(walking for pleasure,light and heavy do-it-yourself activity,strenuous sports,and other exercise)frequency and duration in the 4 weeks prior to evaluation.Apolipoprotein E(APOE)genotype data were available for a subset of 397,519(82.1%)individuals.A Cox proportional hazard model and an isotemporal substitution model were used in this study.Results:During a median 12.4 years of follow-up,6904 all-cause dementia cases and 2115 deaths from dementia were recorded.In comparison to participants with leisure-time SB<5 h/day,the hazard ratio((HR),95%confidence interval(95%CI))of dementia incidence was 1.07(1.02-1.13)for 5-8 h/day and 1.25(1.13-1.38)for>8 h/day,and the HR of dementia mortality was 1.35(1.12-1.61)for>8 h/day.A 1 standard deviation increment of sedentary time(2.33 h/day)was strongly associated with a higher incidence of dementia and mortality(HR=1.06,95%CI:1.03-1.08 and HR=1.07,95%CI:1.03-1.12,respectively).The association between sedentary time and the risk of developing dementia was more profound in subjects<60 years than in those>60 years(HR=1.26,95%CI:1.00-1.58 vs.HR=1.21,95%CI:1.08-1.35 in>8 h/day,p for interaction=0.013).Replacing 30 min/day of leisure sedentary time with an equal time spent in total PA was associated with a6%decreased risk and 9%decreased mortality from dementia,with exercise(e.g.,swimming,cycling,aerobics,bowling)showing the strongest benefit(HR=0.82,95%CI:0.78-0.86 and HR=0.79,95%CI:0.72-0.86).Compared with APOEε4 noncarriers,APOEε4 carriers are more likely to see a decrease in Alzheimer’s disease incidence and mortality when PA is substituted for SB.Conclusion:Leisure-time SB was positively associated with the risk of dementia incidence and mortality.Replacing sedentary time with equal time spent doing PA may be associated with a significant reduction in dementia incidence and mortality risk.
基金supported by the Cross-fund of Nanchang University
文摘The present study was designed to synthesize derivatives of E-resveratrol and evaluate their cytotoxic activity in vitro.Different functional groups were conjugated with the phenolic hydroxyl group of E-resveratrol,and the double bond of E-resveratrol was reduced.The in vitro cytotoxicity of the synthetic derivatives was evaluated against three tumor cell lines(A549,LAC,and He La) using the MTT assay.Twenty-six E-resveratrol derivatives were synthesized and their structures were confirmed by 1H NMR,MS,IR,and elemental analyses.Compounds 1-6,12,15-21,and 23-26 were reported for the first time.Among them,Compounds 1,2,4,5,and 9-11,showed significant cytotoxicity against tumor cells;especially,Compound 1 showed an IC50 value of 4.38 μmol·L-1 in the A549 cells which was 15-fold more active than E-resveratrol;Compound 9 showed an IC50 value of 1.41 μmol·L-1 in the He La cell line which was 90-fold more active than E-resveratrol,and close to adriamycin.The structure–activity relationships were also investigated.Compounds 1,2 and 9-11 may serve as potential lead compounds for the discovery of new anticancer drugs.
文摘Assays of stress enzymes related to active oxygen species were performed by using an in vitro preparation from the liver of a monkey (Japanese Macaque). Ge-132, an organic germanium compound, viz. poly-trans-[(2-carboxyethyl) germasesquioxane] [(GeCH2CH2COOH)2O3]n, suppressed the activities of NADH-dependent oxidase and NADPH-dependent oxidase [NAD(P)H-OD] and xanthine oxidase (XOD) as superoxide-forming enzymes, while promoting the activities of superoxide dismutase (SOD) as a superoxide-scavenging enzyme and catalase (CAT) as an enzyme responsible for degradation of hydrogen peroxide (H2O2). The evidence suggests that the levels of active oxygen species such as and H2O2 would be reduced by Ge-132. The possible connection between Ge-132 and activities of stress enzymes is discussed on the basis of these results.
基金National Natural Science Foundation of China(No.41171241)
文摘Alpine tundra ecosystems have specific vegetation and environmental conditions that may affect soil phosphorus （P） composition and phosphatase activities. However, these effects are poody understood. This study used NaOH-EDTA extraction and solution ^31P nuclear magnetic resonance （NMR） spectroscopy to determine soil P composition and phosphatase activities, including acid phosphomonoesterase （AcP）, phosphodiesterase （PD） and inorganic pyrophosphatase （IPP）, in the alpine tundra of the Changbai Mountains at seven different altitudinal gradients （i.e., 2000 m, 2100 m, 2200 m, 2300 m, 2400 m, 2500 m, and 2600 m）. The results show that total P （TP）, organic P （OP）, OP/TP, NaOH-EDTA extracted P and AcP, PD, and IPP activities over the altitude range of 2500-2600 m are significantly lower than those below 2400 m. The dominant extracted form of P is OP （73%0-83%） with a large proportion of monoesters （65%0-72%）, whereas inorganic P is present in lower proportions （17%-27%）. The activity of AcP is significantly positively correlated with the contents of soil OP, total carbon （TC）, total nitrogen （TN）, and TP （P 〈 0.05）, indicating that the AcP is a more sensitive index for responding P nutrient storage than PD and IPP. Soil properties, P composition, and phosphatase activities decrease with increased altitude and soil pH. Our results indicate that the distribution of soil P composition and phosphatase activities along altitude and AcP may play an important role in P hydrolysis as well as have the potential to be an indicator of soil quality.
文摘Two new zinc（Ⅱ） complexes, [Zn2L2Ch].2[ZnL（CH3OH）Cl2] 1 and [ZnL2（NO3）2] 2, were synthesized by reacting ZnX2.nH2O （X = Cl^-, NO3^-） and a Schiff base ligand 2-[（4-methylphenylimino）methyl]-6-methoxyphenol （C15HIsNO2, L） which was obtained by the condensation of o-vanillin （2-hydroxy-3-methoxybenzaldehyde） with p-toluidine. Both 1 and 2 were characterized by single-crystal X-ray diffraction technique, elemental analysis, molar conductance, FT-IR, UV-Vis, IH-NMR spectra and thermogravimetrie analysis. The Schiff base ligand and its zinc（Ⅱ） complexes have been tested in vitro to evaluate their antibacterial activity against bacteria, viz., Escherichia Coli, Staphylococcus aureus and Bacillus Subtilis. The results show that these complexes have higher activity than the corresponding free Schiff base ligand against the same bacteria.
基金the office of the Higher Education Commission,Thailand for supporting grant fund under the program Strategic Scholarships for Frontier Research Network for the Ph D Program Thai Doctoral degree for this research (77/2551)the 90th Anniversary of Chulalongkorn University Fund (Ratchadaphiseksomphot Endowment Fund,GCUGR11244525026D24)
文摘In vitro biological activities including anti-phytopathogenic fungi, antibacterial, antifeedant and herbicidal activities of the extracts from the heartwoods of Mansonia gagei Drumm. were evaluated. The dichloromethane （DCM） extract displayed antifungal activity against four plant pathogenic fungi （Altemaria porri, Colletotrichum gloeosporioides, Fusarium oxysporum and Phytophthora parasitica） higher than the methanolic （MeOH） extract. The separation of the DCM extract using bioassay guided antifungal activity against P. parasiUca led to the isolation of mansorins A, B, and C, mansonones C, E, G and H. Among isolated compounds, mansonone E displayed the highest antifungal activity against P. parasitica, followed by mansonone C, mansorin B and mansonone G. This potent compound revealed the same minimum inhibitory concentrations （MIC） of 31 μg mL-1 against C. gloeosporioides and P. parasitica, and minimum fungicidal concentration （MFC） of 31 and 125 μg mL-1, respectively. Moreover, mansonone E exhibited highly significant antibacterial activity against both Xanthomonas oryzae pv. oryzae （Xoo） and X. oryzae pv. oryzicola （Xoc） with MIC and minimum bactericidal concentration （MBC） as 7.8 and 〉500μg mL-1, respectively. This compound furthermore could inhibit the feed of Spodoptera litura with 45.9% antifeedant and significantly herbicidal activity reduced the shoot and root growth of Brassica chinensis, Oryza sativa, Mimosa pigra and Echinochlooa crus-galli. Mansonone E has potential as a new natural pesticide for agricultural plant pathogen management.
