In order to elucidate the role of antioxidant responses in salinity tolerance in rice genotypes under salt stress, experiments were conducted using four rice varieties, including salt-sensitive BRRI dhan 28 and three ...In order to elucidate the role of antioxidant responses in salinity tolerance in rice genotypes under salt stress, experiments were conducted using four rice varieties, including salt-sensitive BRRI dhan 28 and three salt-tolerant varieties BRRI dhan 47, BINA dhan 8 and BINA dhan 10. Thirty-day-old rice seedlings were transplanted into pots. At the active tillering stage(35 d after transplanting), plants were exposed to different salinity levels(0, 20, 40 and 60 mmol/L NaCl). Salt stress caused a significant reduction in growth for all the rice genotypes. Growth reduction was higher in the salt-sensitive genotype than in the salt-tolerant ones, and BINA dhan 10 showed higher salt tolerance in all measured physiological parameters. The reduction in shoot and root biomass was found to be minimal in BINA dhan 10. Chlorophyll content significantly decreased under salt stress except for BINA dhan 10. Proline content significantly increased in salt-tolerant rice genotypes with increased salt concentration, and the highest proline content was obtained from BINA dhan 10 under salt stress. Catalase and ascorbate peroxidase activities significantly decreased in salt-sensitive genotype whereas significantly increased in salt-tolerant ones with increasing salt concentration. However, salt stress significantly decreased guaiacol peroxidase activity in all the rice genotypes irrespective of salt tolerance. K^+/Na^+ ratio also significantly decreased in shoots and roots of all the rice genotypes. The salt-tolerant genotype BINA dhan 10 maintained higher levels of chlorophyll and proline contents as well as catalase and ascorbate peroxidase activities under salt stress, thus, this might be the underlying mechanism for salt tolerance.展开更多
Interactions of ciprofloxacin hydrochloride(CPFH)with sodium dodecyl sulfate(SDS)were investigated by conductivity measurement in H2O/electrolyte solutions(NaCl,Na2SO4&Na3PO4)over 298.15–318.15 K temperature rang...Interactions of ciprofloxacin hydrochloride(CPFH)with sodium dodecyl sulfate(SDS)were investigated by conductivity measurement in H2O/electrolyte solutions(NaCl,Na2SO4&Na3PO4)over 298.15–318.15 K temperature range(with 5 K interval)considering the human body temperature.In all cases,two critical micelle concentrations(c*)were observed which are increased in the presence of drug and decreased in the presence of salts enunciating the presence of interaction amongst the studied components.For(CPFH+SDS)system in the presence of salt,the c*values at 303.15 K and I=0.50 mmol·kg^-1 followed the order:CNaCl>CNa2SO4>CNa3PO4.TheΔG1,m0 andΔG2,m0values are found to be negative for all systems that show that the micellization process is thermodynamically spontaneous.For(CPFH+SDS)system in water,theΔHm0&ΔSm0 values reveal that the micellization processes is both entropy dominated in almost all cases.In the occurrence of electrolytes,ΔHm0 andΔSm0 values indicate that micellization processes are both entropy&enthalpy restricted at upper temperature but it becomes totally entropy dependent at higher temperature.The higher positiveΔSm0 values indicate the enhanced hydrophobic interaction in presence of salts.The enthalpy-entropy compensation was determined from the linear relationship betweenΔHm0 andΔSm0 values in every state.Different transfer energies as well as compensation temperature and intrinsic enthalpy were also evaluated and the behaviors were comparable to other biological system.展开更多
Interaction between beta-lactum antibiotic drug ciprofloxacin hydrochloride(CFH)and cationic surfactant cetyltrimethylammonium bromide(CTAB)was performed conductometrically in aqueous as well as in the occurrence of d...Interaction between beta-lactum antibiotic drug ciprofloxacin hydrochloride(CFH)and cationic surfactant cetyltrimethylammonium bromide(CTAB)was performed conductometrically in aqueous as well as in the occurrence of different salts(NaCl,KCl as well as NH_4Cl)over the temperature range of 298.15–323.15 K at the regular interval of 5 K.CFH drug has been suggested for the treatment of bacterial infections such as urinary tract infections and acute sinusitis.A clear critical micelle concentration(CMC)was obtained for pure CTAB as well as(CFH+CTAB)mixed systems.The decrease in CMC values of CTAB caused by the addition of CFH reveals the existence of the interaction between the components and therefore it is the indication of micelle formation at lower concentration of CTAB and their CMC values further decrease in attendance of salts.A nonlinear behavior in the CMC versus T plot was observed in all the cases.The ΔG_m^0 values are found to be negative in present study systems demonstrated the stability of the solution.The values of ΔH_m^0 and ΔS_m^0 reveal the existence of hydrophobic and electrostatic interactions between CFH and CTAB.The thermodynamic properties of transfer for the micellization were also evaluated and discussed in detail.Molecular dynamic simulation disclosed that environment of water and salts have impact on the hydrophobic interaction between CFH and CTAB.In water and salts,CTAB adopts spherical micelle in which charged hydrophilic groups are interacted with waters whereas hydrophobic tails form the core of the micelle.This hydrophobic core region is highly conserved and protected.In addition,micelle formation is more favorable in aqueous Na Cl solution than other solutions.展开更多
Herein,conductivity measurements have been carried out to explore the interaction between cetyltrimethylammonium bromide(CTAB,a cationic surfactant) and antibiotic drug(cefixime trihydrate(CMT)) in water and also in o...Herein,conductivity measurements have been carried out to explore the interaction between cetyltrimethylammonium bromide(CTAB,a cationic surfactant) and antibiotic drug(cefixime trihydrate(CMT)) in water and also in occurrence of inorganic salts(NaCl,Na2 SO4 and Na3 PO4) over the temperature range of 303.15-323.15 K with an interval of 5 K.In all cases,two critical micelle concentrations(c^*) were achieved for the CMT-surfactant system.Addition of CMT drug to CTAB solution decreases the values of c^* which indicates the interaction between CMT and CTAB.Both values of c^* for CMT-CTAB mixture in the presence of salts are lower in magnitude compared to the aqueous medium which indicates that micellization of the CMT-CTAB mixed system is favorable in salt solution.The values of △Gm^0 were obtained to be negative indicating the spontaneity of the micellization process and the extent of spontaneity further increases by means of rising temperature.The obtained outcomes from the ΔHm^0 and ΔSm^0 values disclose that the interactions between CMT and CTAB are mostly electrostatic along with hydrophobic in nature.The thermodynamic parameters of transfer and enthalpy-entropy compensation phenomenon were also determined and discussed in detail.展开更多
The aggregation behavior of the mixture of cetyltrimethylammonium chloride(CTAC), a cationic surfactant, and moxifloxacin hydrochloride(MFH), a fourth-generation fluoroquinolone antibiotic drug, has been studied using...The aggregation behavior of the mixture of cetyltrimethylammonium chloride(CTAC), a cationic surfactant, and moxifloxacin hydrochloride(MFH), a fourth-generation fluoroquinolone antibiotic drug, has been studied using the conductivity technique in aqueous and alcoholic(EtOH, 1-PrOH, and 2-BuOH)media. The study was performed at several temperatures between 298.15 and 323.15 K at 5 K intervals.The assembly has been characterized by evaluating the micellar parameters, such as the critical micelle concentration(CMC) and the counter ion binding(β), of the CTAC + MFH mixture. The values of the CMC for the assembly of the CTAC + MFH mixture were reliant on the composition of alcohols in the mixed solvents and the temperature. The CMC values of the CTAC + MFH mixture increased with increasing temperature;that is, assembly was delayed by increased temperature. The micellization of the CTAC + MFH mixed system was delayed in alcoholic media. The observed-ΔG0mvalues for the association of the CTAC + MFH mixed system demonstrated a spontaneous aggregation process under all study conditions.Based on the-ΔH^(0)_(m) and +ΔS^(0)_(m) values, the association of the CTAC + MFH mixture is exothermic and the interaction forces acting between the CTAC and MFH species are hydrophobic, ion–dipole, and electrostatic interactions. The transfer properties and enthalpy–entropy compensation were also assessed and described comprehensively.展开更多
Irrigation water availability has become a major crisis for rice cultivation in the North-West Barind Tract areas of Bangladesh.Therefore,field experiments were conducted at Mohadebpur,Naogaon and Nachole,Chapainawabg...Irrigation water availability has become a major crisis for rice cultivation in the North-West Barind Tract areas of Bangladesh.Therefore,field experiments were conducted at Mohadebpur,Naogaon and Nachole,Chapainawabganj districts to find out the suitable water savings irrigation technique for sustaining rice productivity and controlling global warming potentials with different combinations of vermicompost,phosphogypsum and chemical fertilizers.The maximum grain yield 6760-6800 kg∙ha^(−1)were recorded in Vermicompost(10 t∙ha^(−1))with Phospho-gypsum(2.5 t∙ha^(−1))amendments along with reduced amount of Nitrogen fertilizer(N 25%of the recommended doze),followed by 6680-6700 kg ha^(−1)(Vermicompost 7.5 t∙ha^(−1)+phospho-gypsum 2.0 t∙ha^(−1)+N 50%RFD)under AWD irrigation.Aerobic irrigation saved 37.0%-39.0%irrigation water,followed by 24.5%-26.0%in alternate wetting and drying irrigation compared to the total required water(30,807 m^(3)ha^(−1))in conventional irrigation.The average cost for irrigation was calculated at 14,825-15,100 Tk∙ha^(−1)under conventional irrigation,which decreased to 11,775-11,850 Tk∙ha^(−1)for alternate wetting and drying,9750-9825 Tk∙ha^(−1)for aerobic irrigation,respectively.The seasonal cumulative CH4 emission and GWPs for boro season rice cultivation significantly decreased with AWD and aerobic irrigation practices.The maximum seasonal cumulative CH4 emission,221 kg/ha and 195-217 kg/ha,was recorded in Vermicompost(2.5 t/ha)with Phospho-gypsum(1.0t∙ha^(−1))amendments under conventional irrigation,which were decreased by 21%-23.0%and 24%-25.0%for AWD and aerobic irrigation practices,respectively.The maximum GWPs value is 4875-5425 kg CO_(2)-eq∙ha^(−1)was estimated for conventional irrigation with vermicompost(2.5 t∙ha^(−1))plus Phospho-gypsum(1.0 t∙ha^(−1))amendments,which was decreased by 19%-21%for AWD and 22%-23%for aerobic irrigations,respectively.Soil physico-chemical properties were also improved with 7.5-10 t∙ha^(−1)vermicompost and 2.0-2.5 t∙ha^(−1)Phospho-gypsum amendments.Conclusively,the integration of environment friendly irrigation water management through alternate wetting and drying(AWD),and aerobic irrigation with Vermicompost amendments(7.5-10 t∙ha^(−1))and half of the recommended Nitrogenous fertilizer application may enhance the synergistic effect towards optimum rice productivity,increased water productivity,improved irrigation cost savings and ensure mitigation of GWPs during dry season irrigated rice cultivation.展开更多
Arsenic(As)is carcinogenic and highly toxic to plants.Crops accumulate As when grown in field soils irrigated with As-contaminated groundwater.The accumulation of As in roots,shoots,and grains of pea varieties can neg...Arsenic(As)is carcinogenic and highly toxic to plants.Crops accumulate As when grown in field soils irrigated with As-contaminated groundwater.The accumulation of As in roots,shoots,and grains of pea varieties can negatively affect human health via the food chain.This research is focused on the biomass growth and alleviation of As accumulation in roots,shoots,and grains of pea varieties in high As soil amended with arbuscular mycorrhizal fungi(AMF),biochar(BC),selenium(Se),silica gel(Si-gel),and sulfur(S).Root,shoot,and grain masses were found higher in pea grown in As soil amended with AMF,Se,Si-gel,and S.Amendments with rice husk and sawdust BC was found less effective to increase growth parameters in Bangladesh Agricultural Research Institute(BARI)Motor 2.Arsenic in grains was reduced by 77%,71%,and 69%by AMF,Se,and Si-gel,respectively.It is recommended that soil amendments with AMF,S,and Se have great potential for improving biomass production of pea grown in As-contaminated soil,as well as reducing As transfer to humans through the food chains.展开更多
基金supported by a grant from the Ministry of Education, Government of Bangladesh
文摘In order to elucidate the role of antioxidant responses in salinity tolerance in rice genotypes under salt stress, experiments were conducted using four rice varieties, including salt-sensitive BRRI dhan 28 and three salt-tolerant varieties BRRI dhan 47, BINA dhan 8 and BINA dhan 10. Thirty-day-old rice seedlings were transplanted into pots. At the active tillering stage(35 d after transplanting), plants were exposed to different salinity levels(0, 20, 40 and 60 mmol/L NaCl). Salt stress caused a significant reduction in growth for all the rice genotypes. Growth reduction was higher in the salt-sensitive genotype than in the salt-tolerant ones, and BINA dhan 10 showed higher salt tolerance in all measured physiological parameters. The reduction in shoot and root biomass was found to be minimal in BINA dhan 10. Chlorophyll content significantly decreased under salt stress except for BINA dhan 10. Proline content significantly increased in salt-tolerant rice genotypes with increased salt concentration, and the highest proline content was obtained from BINA dhan 10 under salt stress. Catalase and ascorbate peroxidase activities significantly decreased in salt-sensitive genotype whereas significantly increased in salt-tolerant ones with increasing salt concentration. However, salt stress significantly decreased guaiacol peroxidase activity in all the rice genotypes irrespective of salt tolerance. K^+/Na^+ ratio also significantly decreased in shoots and roots of all the rice genotypes. The salt-tolerant genotype BINA dhan 10 maintained higher levels of chlorophyll and proline contents as well as catalase and ascorbate peroxidase activities under salt stress, thus, this might be the underlying mechanism for salt tolerance.
基金funded by the Deanship of Scientific Research(DSR)King Abdulaziz University,Jeddah,under grant No.(D-403-130-1441).
文摘Interactions of ciprofloxacin hydrochloride(CPFH)with sodium dodecyl sulfate(SDS)were investigated by conductivity measurement in H2O/electrolyte solutions(NaCl,Na2SO4&Na3PO4)over 298.15–318.15 K temperature range(with 5 K interval)considering the human body temperature.In all cases,two critical micelle concentrations(c*)were observed which are increased in the presence of drug and decreased in the presence of salts enunciating the presence of interaction amongst the studied components.For(CPFH+SDS)system in the presence of salt,the c*values at 303.15 K and I=0.50 mmol·kg^-1 followed the order:CNaCl>CNa2SO4>CNa3PO4.TheΔG1,m0 andΔG2,m0values are found to be negative for all systems that show that the micellization process is thermodynamically spontaneous.For(CPFH+SDS)system in water,theΔHm0&ΔSm0 values reveal that the micellization processes is both entropy dominated in almost all cases.In the occurrence of electrolytes,ΔHm0 andΔSm0 values indicate that micellization processes are both entropy&enthalpy restricted at upper temperature but it becomes totally entropy dependent at higher temperature.The higher positiveΔSm0 values indicate the enhanced hydrophobic interaction in presence of salts.The enthalpy-entropy compensation was determined from the linear relationship betweenΔHm0 andΔSm0 values in every state.Different transfer energies as well as compensation temperature and intrinsic enthalpy were also evaluated and the behaviors were comparable to other biological system.
文摘Interaction between beta-lactum antibiotic drug ciprofloxacin hydrochloride(CFH)and cationic surfactant cetyltrimethylammonium bromide(CTAB)was performed conductometrically in aqueous as well as in the occurrence of different salts(NaCl,KCl as well as NH_4Cl)over the temperature range of 298.15–323.15 K at the regular interval of 5 K.CFH drug has been suggested for the treatment of bacterial infections such as urinary tract infections and acute sinusitis.A clear critical micelle concentration(CMC)was obtained for pure CTAB as well as(CFH+CTAB)mixed systems.The decrease in CMC values of CTAB caused by the addition of CFH reveals the existence of the interaction between the components and therefore it is the indication of micelle formation at lower concentration of CTAB and their CMC values further decrease in attendance of salts.A nonlinear behavior in the CMC versus T plot was observed in all the cases.The ΔG_m^0 values are found to be negative in present study systems demonstrated the stability of the solution.The values of ΔH_m^0 and ΔS_m^0 reveal the existence of hydrophobic and electrostatic interactions between CFH and CTAB.The thermodynamic properties of transfer for the micellization were also evaluated and discussed in detail.Molecular dynamic simulation disclosed that environment of water and salts have impact on the hydrophobic interaction between CFH and CTAB.In water and salts,CTAB adopts spherical micelle in which charged hydrophilic groups are interacted with waters whereas hydrophobic tails form the core of the micelle.This hydrophobic core region is highly conserved and protected.In addition,micelle formation is more favorable in aqueous Na Cl solution than other solutions.
基金Jahangirnagar University, Savar, Dhaka, Bangladesh for providing financial support to carry out the research work
文摘Herein,conductivity measurements have been carried out to explore the interaction between cetyltrimethylammonium bromide(CTAB,a cationic surfactant) and antibiotic drug(cefixime trihydrate(CMT)) in water and also in occurrence of inorganic salts(NaCl,Na2 SO4 and Na3 PO4) over the temperature range of 303.15-323.15 K with an interval of 5 K.In all cases,two critical micelle concentrations(c^*) were achieved for the CMT-surfactant system.Addition of CMT drug to CTAB solution decreases the values of c^* which indicates the interaction between CMT and CTAB.Both values of c^* for CMT-CTAB mixture in the presence of salts are lower in magnitude compared to the aqueous medium which indicates that micellization of the CMT-CTAB mixed system is favorable in salt solution.The values of △Gm^0 were obtained to be negative indicating the spontaneity of the micellization process and the extent of spontaneity further increases by means of rising temperature.The obtained outcomes from the ΔHm^0 and ΔSm^0 values disclose that the interactions between CMT and CTAB are mostly electrostatic along with hydrophobic in nature.The thermodynamic parameters of transfer and enthalpy-entropy compensation phenomenon were also determined and discussed in detail.
基金funded by Institutional Fund Projects (IFPIP:515-961-1443)technical and financial support provided by the Ministry of Education and King Abdulaziz University, DSR, Jeddah, Saudi Arabia。
文摘The aggregation behavior of the mixture of cetyltrimethylammonium chloride(CTAC), a cationic surfactant, and moxifloxacin hydrochloride(MFH), a fourth-generation fluoroquinolone antibiotic drug, has been studied using the conductivity technique in aqueous and alcoholic(EtOH, 1-PrOH, and 2-BuOH)media. The study was performed at several temperatures between 298.15 and 323.15 K at 5 K intervals.The assembly has been characterized by evaluating the micellar parameters, such as the critical micelle concentration(CMC) and the counter ion binding(β), of the CTAC + MFH mixture. The values of the CMC for the assembly of the CTAC + MFH mixture were reliant on the composition of alcohols in the mixed solvents and the temperature. The CMC values of the CTAC + MFH mixture increased with increasing temperature;that is, assembly was delayed by increased temperature. The micellization of the CTAC + MFH mixed system was delayed in alcoholic media. The observed-ΔG0mvalues for the association of the CTAC + MFH mixed system demonstrated a spontaneous aggregation process under all study conditions.Based on the-ΔH^(0)_(m) and +ΔS^(0)_(m) values, the association of the CTAC + MFH mixture is exothermic and the interaction forces acting between the CTAC and MFH species are hydrophobic, ion–dipole, and electrostatic interactions. The transfer properties and enthalpy–entropy compensation were also assessed and described comprehensively.
文摘Irrigation water availability has become a major crisis for rice cultivation in the North-West Barind Tract areas of Bangladesh.Therefore,field experiments were conducted at Mohadebpur,Naogaon and Nachole,Chapainawabganj districts to find out the suitable water savings irrigation technique for sustaining rice productivity and controlling global warming potentials with different combinations of vermicompost,phosphogypsum and chemical fertilizers.The maximum grain yield 6760-6800 kg∙ha^(−1)were recorded in Vermicompost(10 t∙ha^(−1))with Phospho-gypsum(2.5 t∙ha^(−1))amendments along with reduced amount of Nitrogen fertilizer(N 25%of the recommended doze),followed by 6680-6700 kg ha^(−1)(Vermicompost 7.5 t∙ha^(−1)+phospho-gypsum 2.0 t∙ha^(−1)+N 50%RFD)under AWD irrigation.Aerobic irrigation saved 37.0%-39.0%irrigation water,followed by 24.5%-26.0%in alternate wetting and drying irrigation compared to the total required water(30,807 m^(3)ha^(−1))in conventional irrigation.The average cost for irrigation was calculated at 14,825-15,100 Tk∙ha^(−1)under conventional irrigation,which decreased to 11,775-11,850 Tk∙ha^(−1)for alternate wetting and drying,9750-9825 Tk∙ha^(−1)for aerobic irrigation,respectively.The seasonal cumulative CH4 emission and GWPs for boro season rice cultivation significantly decreased with AWD and aerobic irrigation practices.The maximum seasonal cumulative CH4 emission,221 kg/ha and 195-217 kg/ha,was recorded in Vermicompost(2.5 t/ha)with Phospho-gypsum(1.0t∙ha^(−1))amendments under conventional irrigation,which were decreased by 21%-23.0%and 24%-25.0%for AWD and aerobic irrigation practices,respectively.The maximum GWPs value is 4875-5425 kg CO_(2)-eq∙ha^(−1)was estimated for conventional irrigation with vermicompost(2.5 t∙ha^(−1))plus Phospho-gypsum(1.0 t∙ha^(−1))amendments,which was decreased by 19%-21%for AWD and 22%-23%for aerobic irrigations,respectively.Soil physico-chemical properties were also improved with 7.5-10 t∙ha^(−1)vermicompost and 2.0-2.5 t∙ha^(−1)Phospho-gypsum amendments.Conclusively,the integration of environment friendly irrigation water management through alternate wetting and drying(AWD),and aerobic irrigation with Vermicompost amendments(7.5-10 t∙ha^(−1))and half of the recommended Nitrogenous fertilizer application may enhance the synergistic effect towards optimum rice productivity,increased water productivity,improved irrigation cost savings and ensure mitigation of GWPs during dry season irrigated rice cultivation.
文摘Arsenic(As)is carcinogenic and highly toxic to plants.Crops accumulate As when grown in field soils irrigated with As-contaminated groundwater.The accumulation of As in roots,shoots,and grains of pea varieties can negatively affect human health via the food chain.This research is focused on the biomass growth and alleviation of As accumulation in roots,shoots,and grains of pea varieties in high As soil amended with arbuscular mycorrhizal fungi(AMF),biochar(BC),selenium(Se),silica gel(Si-gel),and sulfur(S).Root,shoot,and grain masses were found higher in pea grown in As soil amended with AMF,Se,Si-gel,and S.Amendments with rice husk and sawdust BC was found less effective to increase growth parameters in Bangladesh Agricultural Research Institute(BARI)Motor 2.Arsenic in grains was reduced by 77%,71%,and 69%by AMF,Se,and Si-gel,respectively.It is recommended that soil amendments with AMF,S,and Se have great potential for improving biomass production of pea grown in As-contaminated soil,as well as reducing As transfer to humans through the food chains.
