Background:Andrographis paniculata has been widely reported as an herbal plant for malaria treatment.The increasing rate of resistance to recommended antimalarial drugs has justified the need for a continuous search f...Background:Andrographis paniculata has been widely reported as an herbal plant for malaria treatment.The increasing rate of resistance to recommended antimalarial drugs has justified the need for a continuous search for new and more potent drugs that target all stages of the Plasmodium falciparum life cycle from natural plant sources.This study aimed to determine the antiplasmodial effect of phytocompounds derived from A.paniculata on the stages of plasmodium falciparum.Methods:Phytocompounds from A.paniculata were identified by Gas Chromatography-Mass Spectrophotometry(GCMS)analysis.The phytocompounds were screened for their druggability using Lipinski’s rule of five and subjected to Absorption,Distribution,Metabolism,Excretion,Toxicity(ADMET)and druglikeness analysis.The phytocompounds were docked against some validated drug targets at different stages of Plasmodium falciparum(hepatic,asexual,sexual,and vector targets)using PyRx software to analyze the inhibitory potential and protein-ligand interaction.Thereafter,the stability and flexibility of the best complexes were assessed through molecular dynamics simulations at 50ns using WebGRO.Result:The 7a-Isopropenyl-4,5-dimethyloctahydroinden-4-yl exhibited a higher binding affinity and better stability throughout the simulation period with P.falciparum dihydrofolate reductase-thymidylate synthase and Plasmodium falciparum M1 alanyl aminopeptidase for asexual blood stage and gametocyte stage of Plasmodium falciparum,respectively than the existing drugs.Meanwhile,N-Ethyl-3-methoxy-4-methylphenethylamine was also found to have a higher binding affinity and more stability throughout the simulation period with P.falciparum purine nucleoside phosphorylase and Plasmodium falciparum gametocyte surface protein for Hepatic schizonts stage of Plasmodium falciparum and gametocyte transmission blocking stage,respectively,than the existing drugs.Conclusion:The 7a-Isopropenyl-4,5-dimethyloctahydroinden-4-yl and N-Ethyl-3-methoxy-4 methylphenethylamine from A.paniculata are predicted as an antimalarial drug candidate.Thus,it is recommended that in vitro and in vivo bioassays be conducted on these hit compounds to validate these predictions.展开更多
满天星是当今世界最流行的鲜切花配花之一,茎腐病是满天星的一种常见病害,严重时导致植株枯萎死亡,影响鲜花的观赏性和利用价值,造成一定的经济损失。2021年3月,笔者在云南省昆明市海口镇发现满天星茎腐病,该病主要为害茎基部,表现为茎...满天星是当今世界最流行的鲜切花配花之一,茎腐病是满天星的一种常见病害,严重时导致植株枯萎死亡,影响鲜花的观赏性和利用价值,造成一定的经济损失。2021年3月,笔者在云南省昆明市海口镇发现满天星茎腐病,该病主要为害茎基部,表现为茎基部腐烂和萎蔫。为明确其病原,本研究对满天星茎腐病病原菌进行分离与鉴定。柯赫氏法则证明该分离物可造成满天星组培苗和盆栽苗表现出与田间病株相似的症状,经接种后获得的分离物与田间自然发病的分离物一致。通过形态学鉴定,分离物能产生大量致密的气生菌丝,颜色从白色到淡橙色或黄色不等,菌落背面有暗红色色素沉积。显微镜观察发现其分离物的分生孢子呈镰刀形,腹面较平直,背侧呈拱形,具有3~6个隔膜,分生孢子大小为(21.1~57.9)μm×(2.7~5.1)μm(n=100),未见小型分生孢子,形态学上与镰刀菌属病原真菌相似。通过对其ITS基因序列与形态学鉴定,将分离物初步确定为禾谷镰孢复合种(Fusarium graminearum species complex,FGSC),为进一步确定亚种,使用翻译延伸因子(TEF-1α)序列进行测序,发现该分离物与南方镰孢菌(F.meridionale)的同源性达100%。因此结合形态学和分子生物学特征,满天星茎腐病的病原确定为南方镰孢菌。目前国内尚未发现由南方镰孢菌侵染为害满天星茎部的相关研究报道,本研究结果将为防治满天星病害提供重要理论依据。展开更多
Objective:To investigate the hypoglycemic,hypolipidemic and antioxidant activities of aqueous extract of Terminalia paniculata bark(AETPB) in streptozotocin(STZ)-mduced diabetic rats.Methods:Acute toxicity was studied...Objective:To investigate the hypoglycemic,hypolipidemic and antioxidant activities of aqueous extract of Terminalia paniculata bark(AETPB) in streptozotocin(STZ)-mduced diabetic rats.Methods:Acute toxicity was studied in rats after the oral administration of AETPB to determine the dose to assess hypoglycemic activity.In rats,diabetes was induced by injection of STZ(60 mg/kg,i.p.) and diabetes was confirmed 72 h after induction,and then allowed for 14 days to stabilize blood glucose level.In diabetic rats,AETPB was orally given for 28 days and its effect on blood glucose and body weight was determined on a weekly basis.At the end of the experimental day,fasting blood sample was collected to estimate the haemoglobin(Hb),glycosylated haemoglobin(HbA1c),serum creatinine,urea,serum glutamate-pyruvate transaminase(SGPT),serum glutamate-oxaloacetate transaminase(SGOT) and insulin levels. The liver and kidney were collected to determine antioxidants levels in diabetic rats.Results: Oral administration of AETPB did not exhibit toxicity and death at a dose of 2000 mg/kg.AETPB treated diabetic rats significantly(P<0.001,P<0.01 and P<0.05) reduced elevated blood glucose, HbAlc,creatinine,urea,SGPT and SGOT levels when compared with diabetic control rats.The body weight,Hb,insulin and total protein levels were significantly(P<0.001,P<0.01 and P<0.05) increased in diabetic rats treated with AETPB compared to diabetic control rats.In diabetic rats, AETPB treatment significantly reversed abnormal status of antioxidants and lipid profile levels towards near normal levels compared to diabetic control rats.Conclusions:Present study results confirm that AETPB possesses significant hypoglycemic,hypolipidemic and antioxidant activities in diabetic condition.展开更多
Phytoremediation can be used as a sustainable technology for mine spoil remediation to remove heavy metals. This study investigated the concentration of 7 heavy metal contamination in soil and plant samples at an aban...Phytoremediation can be used as a sustainable technology for mine spoil remediation to remove heavy metals. This study investigated the concentration of 7 heavy metal contamination in soil and plant samples at an abandoned mine site. We found that, after vegetation remediation at the abandoned mine site, the reduction rates for 7 heavy metals were in the range of 4.2%-86%, where reduction rates over 50% were achieved for four heavy metals (Zn, Mn, Cd, Ni). Transfer coefficients of the panicled goldenrain tree (Koelreuteria paniculata Laxm) and the common elaeocarpus (Elaeocarpus decipens) for Zn, Mn, Ni, and Co were more than 1. Enrichment coefficients of both trees for Mn were higher than 1. Our results suggest that the panicled goldenrain tree and the common elaeocarpus tree may act as accumulators in remediation. Moreover, the woody vegetation remediation in abandoned mining areas play an important role in improving scenery besides removing heavy metal from contaminated soil.展开更多
Objective:To investigate the larvicidal and ovicidal efficacy of different extracts of Andrographis paniculata(A.paniculata) against Culex quinquefasciatus(Cx.quinquefasciatus) Say and Aedes aegypti(Ae.aegypti ...Objective:To investigate the larvicidal and ovicidal efficacy of different extracts of Andrographis paniculata(A.paniculata) against Culex quinquefasciatus(Cx.quinquefasciatus) Say and Aedes aegypti(Ae.aegypti ) L(Diptera:Culicidae).Methods:Larvicidal efficacy of the crude leaf extracts of A.paniculata with five different solvents like benzene,hexane,ethyl acetate, methanol and chloroform was tested against the early third instar larvae of Cx.quinquefasciatus and Ae.aegypti.The ovicidal activity was determined against two mosquito species to various concentrations ranging from 50-300 ppm under the laboratory conditions.Results:The benzene, hexane,ethyl acetate,methanol and chloroform leaf extract of A.paniculata was found to be more effective against Cx.quinquefasciatus than Ae.aegypti.The LC<sub>50</sub> values were 112.19,137.48, 118.67,102.05,91.20 ppm and 119.58,146.34,124.24,110.12,99.54 ppm respectively.Among five tested solvent,methanol and ethyl acetate crude extract was found to be most effective for ovicidal activity against two mosquito species.The extract of methanol and ethyl acetate exerted 100%mortality at 200 ppm against Cx.quinquefasciatus and at 250 ppm against Ae.aegypti. Conclusions:From the results it can be concluded the crude extract of A.paniculata was a potential for controlling Cx.quinquefasciatus and Ae.aegypti mosquitoes.展开更多
Objective:To evaluate the hepatoprotective activity of Terminalia paniculata against paracetamol induced hepatic damage in rats.Methods:The plant material was shade dried, powdered and extracted with ethanol.Liv 52 an...Objective:To evaluate the hepatoprotective activity of Terminalia paniculata against paracetamol induced hepatic damage in rats.Methods:The plant material was shade dried, powdered and extracted with ethanol.Liv 52 and silymarin were used as standard drugs and 2%gum acacia as a control(vehicle).Alteration in the levels of biochemical markers of hepatic damage like AST,ALT,ALP and lipid peroxides were tested,and phytochemical tests were also performed.Results:Paracetamol(2 g/kg) increased the serum levels of alanine aminotransfer (ALT),aspartate aminotransferase(AST),alkaline phosphatase(ALP) and the lipid peroxides. Treatment of Liv 52,silymarin and ethanolic extract of Terminalia paniculata(200 mg/kg) altered levels of biochemical marker and showed significant hepatoprotective activity.Ethanolic extract revealed the presence of phenolic compound and flavanoids.Our findings suggested that ethanolic bark extract of Terminalia paniculata possessed hepatoprotective activity in a dose dependent manner.Conclusions:Terminalia paniculata possesses hepatoprotective activity.It could be an effective and promising preventive agent against PCT induced hepatotoxicity.展开更多
The objective of this paper is to demonstrate whether air plasma can change the seed germination characteristics, seedling emergence, as well as biochemical reactivity, in Andrographis paniculata (A. paniculata) see...The objective of this paper is to demonstrate whether air plasma can change the seed germination characteristics, seedling emergence, as well as biochemical reactivity, in Andrographis paniculata (A. paniculata) seedlings by modifying the seed coat and finding a beneficial treatment dose. Eight treatment doses and one control were used to conduct electrical conductivity determination, a germination test, a seedling emergence test and a biochemical assay. The results showed that after being treated with air plasma excited at 5950 V for 10 s, the perme- ability of the seeds was improved significantly, resulting in the acceleration of seed germination and seedling emergence. In the meantime, the catalase activity and catalase isoenzyme expression were also improved, while the malondialdehyde content in the seedlings was decreased (which means greater counteraction with environmental stress). After being treated with 4250 V for 10 s and 5950 V for 20 s, the seed germination was enhanced, but without an obvious change in seedUng emergence. However, after treatment with 3400 V for 20 s and 5100 V for 10 s, the permeability of the seeds was decreased, resulting in a delay in seedling emergence. These results indicate that air plasma can change the physiological and biochemical characteristics of Andrographis paniculata seeds by modifying the seed coat, combined with the effects of the active plasma species, and that different treating doses have different effects.展开更多
Objective: To investigate the effects of Andrographis paniculata(Burm.f.) Wall. Ex Nees(A. paniculata) on expressions and activities of catalase, superoxide dismutase and alkylhydroperoxide reductase C in Staphylococc...Objective: To investigate the effects of Andrographis paniculata(Burm.f.) Wall. Ex Nees(A. paniculata) on expressions and activities of catalase, superoxide dismutase and alkylhydroperoxide reductase C in Staphylococcus aureus(S. aureus) with respect to its survival in vitro. Methods: Antioxidative property of methanolic leaves extract of A. paniculata(0.06 mg/m L). Minimum inhibitory concentration(MIC) was determined by its ability to reduce hydrogen peroxide(H_2O_2) toxicity against S. aureus ATCC 25923(3.8×10~8 cfu/m L). Effects of the extract on expressions of kat A(encoding catalase), sod A and sod M [encoding superoxide dismutases(SODs)], and ahp C [encoding alkylhydroperoxide reductase C(AhpC)] in S. aureuswere determined by RT-q PCR and corresponding enzyme activity assays were performed. Nitroblue tetrazolium reduction(NBT) assay was performed to determine effects of the extract on intracellular and extracellular levels of O_2-in S. aureus. Results: Cells challenged with 7.5 mmol/L H_2O_2 showed 0% survival in 30 min whereas 25% survived after treatment with the extract and H_2O_2. Cells that were treated with the extract alone had 43% survival in the same exposure period. Expressions of sod A and sod M genes in extract-treated cells were lowered 0.8-fold and 0.7-fold, respectively with decrease in total SOD activity of 26.8 U compared to untreated cells, 32.4 U(P<0.05). In contrast, extract-treated S. aureus cells showed 3.3-fold increase in kat A expression with corresponding increase in catalase activity of 1.828 U compared to untreated cells which was 1.248 U,(P<0.05). More profoundly, ahp C expression was increased 61-fold in extract-treated cells,(P<0.05) with corresponding increase in Ahp C activity of 0.018 U compared to untreated cells, 0.012U,(P<0.05). Extract-treated cells had significantly lower intra-and extracellular O_2-levels with absorbance readings(A_(575nm)) of 0.340 and 0.524 compared to untreated cells which were 0.516 and 0.928(P<0.05), respectively. Conclusions: Taken together these results suggest that the low MIC of A. paniculatamethanolic leaves extract(0.06 mg/m L) reduce H_2O_2 toxicity and more importantly, was in itself effectively inhibitory against S. aureus. Further, our observations suggest that a probable mode of its inhibitory mechanism against S. aureus is by reducing total SOD activity through downregulation of sod A and sod M expressions.展开更多
Murraya paniculata(L.),a well-known medical plant,has widely been used to treat inflammation,stomach ache,internal and external injuries,and for other purposes.In this study,we determined the reducing,lipid peroxidati...Murraya paniculata(L.),a well-known medical plant,has widely been used to treat inflammation,stomach ache,internal and external injuries,and for other purposes.In this study,we determined the reducing,lipid peroxidation inhibition,1,1-diphenyl-2-picryl-hydrazil radical(DPPH•)scavenging,superoxide anion radical(O2−•)scavenging,hydroxyl radical(HO•)scavenging and hydrogen peroxide(H2O2)scavenging activities of the methanolic extract of M.paniculata(MPE)by UV–vis spectrophotometer.The results showed that M.paniculata was rich in flavonoids(375 mg RE/g of extract).Reducing,lipid peroxidation inhibition and HO•scavenging activities of the extract were 0.26 mg/mL,0.023 mg/mL and 0.302 mg/mL,respectively,these activities were significantly higher than those of trolox.Other antioxidative behavior indicators,i.e.,DPPH•scavenging,O2−•scavenging and H2O2 scavenging activities of MPE were 0.93 mg/mL,0.581 mg/mL and 0.47 mg/mL,respectively,and were comparable to those exhibited by trolox.These results indicate that the methanolic extract of M.paniculata exhibited strong antioxidative and radical scavenging activities.展开更多
文摘Background:Andrographis paniculata has been widely reported as an herbal plant for malaria treatment.The increasing rate of resistance to recommended antimalarial drugs has justified the need for a continuous search for new and more potent drugs that target all stages of the Plasmodium falciparum life cycle from natural plant sources.This study aimed to determine the antiplasmodial effect of phytocompounds derived from A.paniculata on the stages of plasmodium falciparum.Methods:Phytocompounds from A.paniculata were identified by Gas Chromatography-Mass Spectrophotometry(GCMS)analysis.The phytocompounds were screened for their druggability using Lipinski’s rule of five and subjected to Absorption,Distribution,Metabolism,Excretion,Toxicity(ADMET)and druglikeness analysis.The phytocompounds were docked against some validated drug targets at different stages of Plasmodium falciparum(hepatic,asexual,sexual,and vector targets)using PyRx software to analyze the inhibitory potential and protein-ligand interaction.Thereafter,the stability and flexibility of the best complexes were assessed through molecular dynamics simulations at 50ns using WebGRO.Result:The 7a-Isopropenyl-4,5-dimethyloctahydroinden-4-yl exhibited a higher binding affinity and better stability throughout the simulation period with P.falciparum dihydrofolate reductase-thymidylate synthase and Plasmodium falciparum M1 alanyl aminopeptidase for asexual blood stage and gametocyte stage of Plasmodium falciparum,respectively than the existing drugs.Meanwhile,N-Ethyl-3-methoxy-4-methylphenethylamine was also found to have a higher binding affinity and more stability throughout the simulation period with P.falciparum purine nucleoside phosphorylase and Plasmodium falciparum gametocyte surface protein for Hepatic schizonts stage of Plasmodium falciparum and gametocyte transmission blocking stage,respectively,than the existing drugs.Conclusion:The 7a-Isopropenyl-4,5-dimethyloctahydroinden-4-yl and N-Ethyl-3-methoxy-4 methylphenethylamine from A.paniculata are predicted as an antimalarial drug candidate.Thus,it is recommended that in vitro and in vivo bioassays be conducted on these hit compounds to validate these predictions.
文摘满天星是当今世界最流行的鲜切花配花之一,茎腐病是满天星的一种常见病害,严重时导致植株枯萎死亡,影响鲜花的观赏性和利用价值,造成一定的经济损失。2021年3月,笔者在云南省昆明市海口镇发现满天星茎腐病,该病主要为害茎基部,表现为茎基部腐烂和萎蔫。为明确其病原,本研究对满天星茎腐病病原菌进行分离与鉴定。柯赫氏法则证明该分离物可造成满天星组培苗和盆栽苗表现出与田间病株相似的症状,经接种后获得的分离物与田间自然发病的分离物一致。通过形态学鉴定,分离物能产生大量致密的气生菌丝,颜色从白色到淡橙色或黄色不等,菌落背面有暗红色色素沉积。显微镜观察发现其分离物的分生孢子呈镰刀形,腹面较平直,背侧呈拱形,具有3~6个隔膜,分生孢子大小为(21.1~57.9)μm×(2.7~5.1)μm(n=100),未见小型分生孢子,形态学上与镰刀菌属病原真菌相似。通过对其ITS基因序列与形态学鉴定,将分离物初步确定为禾谷镰孢复合种(Fusarium graminearum species complex,FGSC),为进一步确定亚种,使用翻译延伸因子(TEF-1α)序列进行测序,发现该分离物与南方镰孢菌(F.meridionale)的同源性达100%。因此结合形态学和分子生物学特征,满天星茎腐病的病原确定为南方镰孢菌。目前国内尚未发现由南方镰孢菌侵染为害满天星茎部的相关研究报道,本研究结果将为防治满天星病害提供重要理论依据。
基金financially supported by Canara Bank,Zamin Uthukuli(grant No.133765125313)
文摘Objective:To investigate the hypoglycemic,hypolipidemic and antioxidant activities of aqueous extract of Terminalia paniculata bark(AETPB) in streptozotocin(STZ)-mduced diabetic rats.Methods:Acute toxicity was studied in rats after the oral administration of AETPB to determine the dose to assess hypoglycemic activity.In rats,diabetes was induced by injection of STZ(60 mg/kg,i.p.) and diabetes was confirmed 72 h after induction,and then allowed for 14 days to stabilize blood glucose level.In diabetic rats,AETPB was orally given for 28 days and its effect on blood glucose and body weight was determined on a weekly basis.At the end of the experimental day,fasting blood sample was collected to estimate the haemoglobin(Hb),glycosylated haemoglobin(HbA1c),serum creatinine,urea,serum glutamate-pyruvate transaminase(SGPT),serum glutamate-oxaloacetate transaminase(SGOT) and insulin levels. The liver and kidney were collected to determine antioxidants levels in diabetic rats.Results: Oral administration of AETPB did not exhibit toxicity and death at a dose of 2000 mg/kg.AETPB treated diabetic rats significantly(P<0.001,P<0.01 and P<0.05) reduced elevated blood glucose, HbAlc,creatinine,urea,SGPT and SGOT levels when compared with diabetic control rats.The body weight,Hb,insulin and total protein levels were significantly(P<0.001,P<0.01 and P<0.05) increased in diabetic rats treated with AETPB compared to diabetic control rats.In diabetic rats, AETPB treatment significantly reversed abnormal status of antioxidants and lipid profile levels towards near normal levels compared to diabetic control rats.Conclusions:Present study results confirm that AETPB possesses significant hypoglycemic,hypolipidemic and antioxidant activities in diabetic condition.
基金As a key project under the State Forestry Administration of China (2006-11, 2006-17, 2005-08)this project was funded by the National Natural Science Foundation of China (No. 30571487, 30771700)+1 种基金the Furong Scholar Program, the Urban Forest Ecological Key Laboratory of Hunan Province (No. 06FJ3083)the Platform Construction Project under the Ministry of Science and Technology of China
文摘Phytoremediation can be used as a sustainable technology for mine spoil remediation to remove heavy metals. This study investigated the concentration of 7 heavy metal contamination in soil and plant samples at an abandoned mine site. We found that, after vegetation remediation at the abandoned mine site, the reduction rates for 7 heavy metals were in the range of 4.2%-86%, where reduction rates over 50% were achieved for four heavy metals (Zn, Mn, Cd, Ni). Transfer coefficients of the panicled goldenrain tree (Koelreuteria paniculata Laxm) and the common elaeocarpus (Elaeocarpus decipens) for Zn, Mn, Ni, and Co were more than 1. Enrichment coefficients of both trees for Mn were higher than 1. Our results suggest that the panicled goldenrain tree and the common elaeocarpus tree may act as accumulators in remediation. Moreover, the woody vegetation remediation in abandoned mining areas play an important role in improving scenery besides removing heavy metal from contaminated soil.
基金the Department of Science and Technology(DST)(SERC-Fast Track Young Scientist Project),New Delhi,India for providing financial assistance for the present investigation
文摘Objective:To investigate the larvicidal and ovicidal efficacy of different extracts of Andrographis paniculata(A.paniculata) against Culex quinquefasciatus(Cx.quinquefasciatus) Say and Aedes aegypti(Ae.aegypti ) L(Diptera:Culicidae).Methods:Larvicidal efficacy of the crude leaf extracts of A.paniculata with five different solvents like benzene,hexane,ethyl acetate, methanol and chloroform was tested against the early third instar larvae of Cx.quinquefasciatus and Ae.aegypti.The ovicidal activity was determined against two mosquito species to various concentrations ranging from 50-300 ppm under the laboratory conditions.Results:The benzene, hexane,ethyl acetate,methanol and chloroform leaf extract of A.paniculata was found to be more effective against Cx.quinquefasciatus than Ae.aegypti.The LC<sub>50</sub> values were 112.19,137.48, 118.67,102.05,91.20 ppm and 119.58,146.34,124.24,110.12,99.54 ppm respectively.Among five tested solvent,methanol and ethyl acetate crude extract was found to be most effective for ovicidal activity against two mosquito species.The extract of methanol and ethyl acetate exerted 100%mortality at 200 ppm against Cx.quinquefasciatus and at 250 ppm against Ae.aegypti. Conclusions:From the results it can be concluded the crude extract of A.paniculata was a potential for controlling Cx.quinquefasciatus and Ae.aegypti mosquitoes.
文摘Objective:To evaluate the hepatoprotective activity of Terminalia paniculata against paracetamol induced hepatic damage in rats.Methods:The plant material was shade dried, powdered and extracted with ethanol.Liv 52 and silymarin were used as standard drugs and 2%gum acacia as a control(vehicle).Alteration in the levels of biochemical markers of hepatic damage like AST,ALT,ALP and lipid peroxides were tested,and phytochemical tests were also performed.Results:Paracetamol(2 g/kg) increased the serum levels of alanine aminotransfer (ALT),aspartate aminotransferase(AST),alkaline phosphatase(ALP) and the lipid peroxides. Treatment of Liv 52,silymarin and ethanolic extract of Terminalia paniculata(200 mg/kg) altered levels of biochemical marker and showed significant hepatoprotective activity.Ethanolic extract revealed the presence of phenolic compound and flavanoids.Our findings suggested that ethanolic bark extract of Terminalia paniculata possessed hepatoprotective activity in a dose dependent manner.Conclusions:Terminalia paniculata possesses hepatoprotective activity.It could be an effective and promising preventive agent against PCT induced hepatotoxicity.
基金supported by the Science and Technology Planning Project of Beijing,China(Z090605006009022)
文摘The objective of this paper is to demonstrate whether air plasma can change the seed germination characteristics, seedling emergence, as well as biochemical reactivity, in Andrographis paniculata (A. paniculata) seedlings by modifying the seed coat and finding a beneficial treatment dose. Eight treatment doses and one control were used to conduct electrical conductivity determination, a germination test, a seedling emergence test and a biochemical assay. The results showed that after being treated with air plasma excited at 5950 V for 10 s, the perme- ability of the seeds was improved significantly, resulting in the acceleration of seed germination and seedling emergence. In the meantime, the catalase activity and catalase isoenzyme expression were also improved, while the malondialdehyde content in the seedlings was decreased (which means greater counteraction with environmental stress). After being treated with 4250 V for 10 s and 5950 V for 20 s, the seed germination was enhanced, but without an obvious change in seedUng emergence. However, after treatment with 3400 V for 20 s and 5100 V for 10 s, the permeability of the seeds was decreased, resulting in a delay in seedling emergence. These results indicate that air plasma can change the physiological and biochemical characteristics of Andrographis paniculata seeds by modifying the seed coat, combined with the effects of the active plasma species, and that different treating doses have different effects.
基金supported by the Faculty of Health Sciences,Universiti Teknologi MARA,Puncak Alam Campus,Selangor and LESTARI grant(600-IRMI/MYRA 5/3/LESTARI(16/2016)
文摘Objective: To investigate the effects of Andrographis paniculata(Burm.f.) Wall. Ex Nees(A. paniculata) on expressions and activities of catalase, superoxide dismutase and alkylhydroperoxide reductase C in Staphylococcus aureus(S. aureus) with respect to its survival in vitro. Methods: Antioxidative property of methanolic leaves extract of A. paniculata(0.06 mg/m L). Minimum inhibitory concentration(MIC) was determined by its ability to reduce hydrogen peroxide(H_2O_2) toxicity against S. aureus ATCC 25923(3.8×10~8 cfu/m L). Effects of the extract on expressions of kat A(encoding catalase), sod A and sod M [encoding superoxide dismutases(SODs)], and ahp C [encoding alkylhydroperoxide reductase C(AhpC)] in S. aureuswere determined by RT-q PCR and corresponding enzyme activity assays were performed. Nitroblue tetrazolium reduction(NBT) assay was performed to determine effects of the extract on intracellular and extracellular levels of O_2-in S. aureus. Results: Cells challenged with 7.5 mmol/L H_2O_2 showed 0% survival in 30 min whereas 25% survived after treatment with the extract and H_2O_2. Cells that were treated with the extract alone had 43% survival in the same exposure period. Expressions of sod A and sod M genes in extract-treated cells were lowered 0.8-fold and 0.7-fold, respectively with decrease in total SOD activity of 26.8 U compared to untreated cells, 32.4 U(P<0.05). In contrast, extract-treated S. aureus cells showed 3.3-fold increase in kat A expression with corresponding increase in catalase activity of 1.828 U compared to untreated cells which was 1.248 U,(P<0.05). More profoundly, ahp C expression was increased 61-fold in extract-treated cells,(P<0.05) with corresponding increase in Ahp C activity of 0.018 U compared to untreated cells, 0.012U,(P<0.05). Extract-treated cells had significantly lower intra-and extracellular O_2-levels with absorbance readings(A_(575nm)) of 0.340 and 0.524 compared to untreated cells which were 0.516 and 0.928(P<0.05), respectively. Conclusions: Taken together these results suggest that the low MIC of A. paniculatamethanolic leaves extract(0.06 mg/m L) reduce H_2O_2 toxicity and more importantly, was in itself effectively inhibitory against S. aureus. Further, our observations suggest that a probable mode of its inhibitory mechanism against S. aureus is by reducing total SOD activity through downregulation of sod A and sod M expressions.
文摘Murraya paniculata(L.),a well-known medical plant,has widely been used to treat inflammation,stomach ache,internal and external injuries,and for other purposes.In this study,we determined the reducing,lipid peroxidation inhibition,1,1-diphenyl-2-picryl-hydrazil radical(DPPH•)scavenging,superoxide anion radical(O2−•)scavenging,hydroxyl radical(HO•)scavenging and hydrogen peroxide(H2O2)scavenging activities of the methanolic extract of M.paniculata(MPE)by UV–vis spectrophotometer.The results showed that M.paniculata was rich in flavonoids(375 mg RE/g of extract).Reducing,lipid peroxidation inhibition and HO•scavenging activities of the extract were 0.26 mg/mL,0.023 mg/mL and 0.302 mg/mL,respectively,these activities were significantly higher than those of trolox.Other antioxidative behavior indicators,i.e.,DPPH•scavenging,O2−•scavenging and H2O2 scavenging activities of MPE were 0.93 mg/mL,0.581 mg/mL and 0.47 mg/mL,respectively,and were comparable to those exhibited by trolox.These results indicate that the methanolic extract of M.paniculata exhibited strong antioxidative and radical scavenging activities.