BACKGROUND The investigation of plant-based therapeutic agents in medicinal plants has revealed their presence in the extracts and provides the vision to formulate novel techniques for drug therapy.Vitex negundo(V.neg...BACKGROUND The investigation of plant-based therapeutic agents in medicinal plants has revealed their presence in the extracts and provides the vision to formulate novel techniques for drug therapy.Vitex negundo(V.negundo),a perennial herb belonging to the Varbanaceae family,is extensively used in conventional medication.AIM To determine the existence of therapeutic components in leaf and callus extracts from wild V.negundo plants using gas chromatography-mass spectrometry(GCMS).METHODS In this study,we conducted GC-MS on wild plant leaf extracts and correlated the presence of constituents with those in callus extracts.Various growth regulators such as 6-benzylaminopurine(BAP),2,4-dichlorophenoxyacetic acid(2,4-D),α-naphthylacetic acid(NAA),and di-phenylurea(DPU)were added to plant leaves and in-vitro callus and grown on MS medium.RESULTS The results clearly indicated that the addition of BAP(2.0 mg/L),2,4-D(0.2 mg/mL),DPU(2.0 mg/L)and 2,4-D(0.2 mg/mL)in MS medium resulted in rapid callus development.The plant profile of Vitex extracts by GC-MS analysis showed that 24,10,and 14 bioactive constituents were detected in the methanolic extract of leaf,green callus and the methanolic extract of white loose callus,respectively.CONCLUSION Octadecadienoic acid,hexadecanoic acid and methyl ester were the major constituents in the leaf and callus methanolic extract.Octadecadienoic acid was the most common constituent in all samples.The maximum concentration of octadecadienoic acid in leaves,green callus and white loose callus was 21.93%,47.79%and 40.38%,respectively.These findings demonstrate that the concentration of octadecadienoic acid doubles in-vitro compared to in-vivo.In addition to octadecadienoic acid;butyric acid,benzene,1-methoxy-4-(1-propenyl),dospan,tridecanedialdehyde,methylcyclohexenylbutanol,chlorpyrifos,n-secondary terpene diester,anflunine and other important active compounds were also detected.All these components were only available in callus formed in-vitro.This study showed that the callus contained additional botanical characteristics compared with wild plants.Due to the presence of numerous bioactive compounds,the medical use of Vitex for various diseases has been accepted and the plant is considered an important source of therapeutics for research and development.展开更多
Objective:To evaluate the antidiabetic potential of methanolic extract of Albizia odoratissima Benth.bark in alloxan induced diabetic mice.Methods:Group-Ⅰ(normal control) mice received only basal diet without any tre...Objective:To evaluate the antidiabetic potential of methanolic extract of Albizia odoratissima Benth.bark in alloxan induced diabetic mice.Methods:Group-Ⅰ(normal control) mice received only basal diet without any treatment.In Group-Ⅱ(Diabetic control) mice,diabetes was induced by alloxan(150 mg/kg i.p.) and received only Tween 80.5%v/v in normal saline. Group-Ⅲand Group-Ⅳmice received metformin(10 mg/kg) and gliclazide(10 mg/kg) as standard drugs.Group-ⅤandⅥmice received methanolic bark extract of Albizia odoratissima at doses of 250 and 500 mg/kg body weight p.o.,respectively.Results:The results of the study indicates that Albizia odoratissima bark extract significantly(P【0.01) reduced the blood sugar level.The bark extract also significantly reduced the levels of serum cholesterol,triglycerides, serum glutamic-oxaloacetic transaminase,serum glutamic-pyruvic transaminase,alkaline phosphatase and decreases level of total proteins in alloxan induced diabetic mice.Conclusions: Methanolic extract of Albizia odoratissima has protective effects on the protection of vital tissues(pancreas,kidney,liver,heart and spleen),thereby reducing the causation of diabetes in experimental animals.展开更多
Objective: To evaluate the effects of methanol root extract of Mahonia leschenaultii and berberine of Mahonia leschenaultii on Dalton’s ascitic lymphoma in Swiss Albino mice. Methods: The methanol root extracts of Ma...Objective: To evaluate the effects of methanol root extract of Mahonia leschenaultii and berberine of Mahonia leschenaultii on Dalton’s ascitic lymphoma in Swiss Albino mice. Methods: The methanol root extracts of Mahonia leschenaultii(200 and 400 mg/kg) were given orally, and berberines(10 and 20 mg/kg) were injected intra-peritoneally for 14 successive days in tumor bearing mice. Hematological parameters(white and red blood cells, haemoglobin level, granulocytes, and agranulocytes), lipid parameters(total cholesterol and triglycerides), serum enzymes(serum glutamate pyruvate transaminases, serum glutamate oxaloacetate transaminases, and alkaline phosphatise) and mean survival and solid tumor growth were determined and compared with untreated mice. 5-fluorouracil(20 mg/kg) was used as a reference standard drug. Results: Mahonia leschenaultii and berberine reduced the hematocrit significantly. Furthermore, Mahonia leschenaultii and berberine improved the survival of mice significantly and restored the affected hematological and lipid parameters similar to the normal levels. Conclusions: These observations show a strong anticancer effect of methanol root extract of Mahonia leschenaultii and berberine in suppressing Dalton’s ascitic lymphoma cancer cell growth in a mouse model by controlling haematological, lipid, serum enzymes, and other derived parameters effectively.展开更多
A bacterial field isolate recovered from infected tomato plants in a green-house at Sidi Rehal, a region near Casablanca city (Morocco), was identified as the gammaproteobacterium Pseudomonas syringae pv. tomato DC300...A bacterial field isolate recovered from infected tomato plants in a green-house at Sidi Rehal, a region near Casablanca city (Morocco), was identified as the gammaproteobacterium Pseudomonas syringae pv. tomato DC3000 strain, the causal agent of bacterial speck. The bacterial isolate was characterized by morphological, biochemical and molecular biological tests, its growth curves carried out in various culture media, and its phytopathogenicity verified by infection tests. A screening was performed to evaluate the antibacterial activity of methanolic extracts of 12 selected Moroccan plants against the P. syringae pv. tomato DC3000 isolate, and Agar-well diffusion and Broth microdilution methods were used to determine minimum inhibitory and minimum bactericidal concentrations. Among the methanolic extracts tested, only those of Nigella sativa, Geranuim robertianum, Aizoon canariense and Rubia peregrine showed clear inhibitory and bactericidal activities, although the highest values were achieved with N. sativa, a plant used in Morocco as a spice, condiment and medicinal treatment.展开更多
Objective:Acorus calamus(AC)L.(Araceae)is an annual semi-aquatic and aromatic plant found in Europe,North America and Asia.Its rhizomes are often used by Native Americans,Americans,and Chinese as well as by other cult...Objective:Acorus calamus(AC)L.(Araceae)is an annual semi-aquatic and aromatic plant found in Europe,North America and Asia.Its rhizomes are often used by Native Americans,Americans,and Chinese as well as by other cultures.Ethnobotanical studies and documents have shown their use in various disease treatments,such as insomnia,mental disorders,diabetes mellitus,epilepsy,inflammation,asthma,neuropathic pain,and diarrhea.In this study,the antidepressant activity of methanolic and hydroalcoholic extracts of the AC rhizome part in mice was investigated.Methods:Three doses of methanolic extract of AC rhizome(MEACR)(25,50 and 100 mg/kg b.wt),three doses of hydroalcoholic extract of AC rhizome(HAACR)(100,200 and 400 mg/kg b.wt),and standards(imipramine,15 mg/kg b.wt and fluoxetine,20 mg/kg b.wt)was daily oral administration to the mice for consecutive 14 days.The extract effect on the immobility time was monitored by a tail suspension test(TST)and a forced swimming test(FST).Monoamine oxidase(MAO)levels were also analyzed using standard methods.Results:The optimum antidepressant activity was viewed at 100 mg/kg b.wt of MEACR extract and400 mg/kg b.wt of HAACR extract with 23.82%and 20.59%immobility period reduction,respectively.Besides,the extracts weakened the FST-induced elevation of MAO activity significantly and returned to near-normal levels of neurotransmitters in the brain.100 mg/kg b.wt or above of MEACR extract significantly prevented the MAO-A and MAO-B activities in mice brain at a dose-dependent fashion.But,just 400 mg/kg b.wt of HAACR extract prevented the activity of MAO-A and MAO-B.Fluoxetine and imipramine showed a tendency to prevent the activity of MAO-A and MAO-B.Conclusion:This study suggests that AC rhizome extract mediated antidepressant activity by modulating the central neurochemical and hypothalamic-pituitary-adrenal(HPA)axis in response to FST and TSTinduced stress.Therefore,AC rhizome extract can be used as a valuable plant supplement to treat depressive disorders.展开更多
The current study was carried out to determine the bioactivity of P. lentiscus leaf extracts as potential antibacterial and antioxidant properties. The plant extracts were examined for antibacterial activity against a...The current study was carried out to determine the bioactivity of P. lentiscus leaf extracts as potential antibacterial and antioxidant properties. The plant extracts were examined for antibacterial activity against antibiotic-resistant Staphylococcus aureus, Staphylococcus haemolyticus, Pseudomonas aeruginosa, and Proteus mirabilis using the agar well method (according to the guidelines of Clinical and Laboratory Standard Institute). The antioxidant potential of 3 plant leaf extracts was determined by their ability to convert Fe<sup>3+</sup> to Fe<sup>2+</sup> and scavenge the DPPH free radical. At all concentrations studied, the methanolic leaf extract had higher total phenolic and flavonoid content, as well as stronger antioxidant and antibacterial inhibitory activity compared to aqueous extract. Our findings with P. aeruginosa were especially interesting, because this bacterium was inhibited by methanol extract than that of the reference antibiotics. The results also demonstrated a link between DPPH radical scavenging ability, reducing power, and total phenolic and flavonoid content of plant extracts (r > 0.97, R<sup>2</sup> > 0.95, P = 0.01). As a result, the methanolic leaf extract of the chosen plant might be employed as an effective antioxidant and antibacterial agent for the treatment of a variety of morbidities.展开更多
The acetyl ester plays an important role for protection of the hydroxyl groups in carbohydrates synthesis.In the present study,we described an efficient deprotection of acetyl group of pentacyclic triterpenoid by usin...The acetyl ester plays an important role for protection of the hydroxyl groups in carbohydrates synthesis.In the present study,we described an efficient deprotection of acetyl group of pentacyclic triterpenoid by using methanolic ammonia in THF solution.Good selectivity for cleaving gal-C2-OAc group of 3β-hydroxy-olean-12-en-28-oic acid 28-N-2,3,4,6-tetra-O-acetyl-β-D-galactopyranoside(3) was achieved in the presence of methanolic ammonia within 4 h at low temperature(-60℃) in a yield of 56%.The reaction disclosed here provides a new method for the synthesis of C2 selective modified carbohydrates,which is more useful than conventional synthesis procedure that usually requires many steps including temporary regioselective protection and deprotection.When the reaction temperature was increased from -60℃ to room temperature,the cleavage of the other three acetyl groups of galactose in an order of C4-OAc>C3-OAc>C6-OAc was observed.Based on this study,a plausible route for the deacetylation reaction has been proposed.展开更多
This present study was aimed to investigate the antidiabetic and antihyperlipidemic activities of methanolic leaf extract (LE) of Stephania japonica alone and in combination with metformin in alloxan induced diabetic ...This present study was aimed to investigate the antidiabetic and antihyperlipidemic activities of methanolic leaf extract (LE) of Stephania japonica alone and in combination with metformin in alloxan induced diabetic rats. Primarily acute toxicity study and oral glucose tolerance test were performed. Diabetes was confirmed after 12 days of single intraperitoneal injection of alloxan (120 mg/kg BW) in albino male rats. Rats were divided into six groups’;normal control (Group I) and diabetic induced groups as (Group II, III, IV, V and VI). Group III & IV were treated with leaf extract of S. japonica (200 mg/kg BW & 350 mg/kg BW). Group V (Met 850 mg/70 kg BW) and group VI: (combination of Met 425 mg/70 kg BW and LE 250 mg/kg BW) for four weeks. Body weight of each rat in the different groups was recorded at 0, 7th, 14th, 21st and 28th day of treatment. TC, TG, LDL-C and HDL-C were measured analytically after 28 days of treatment. Alloxan induction also caused left ventricular hypertrophy. LE of S. Japonica showed a good result in OGTT. Oral treatment of different doses of LE and combination therapy reduced elevated level of BG, TC, TG, LDL-C and increased HDL-C level significantly (p S. japonica (Thunb.) Miers showed antihyperlipidemic and antidiabetic effect and hence could be suggested as a potential therapeutic agent for diabetic treatment.展开更多
Present study aims to evaluate antimicrobial and antioxidant activities of the crude methanolic extract and different fractions of the <i><span style="font-family:Verdana;">Epilobium</span>...Present study aims to evaluate antimicrobial and antioxidant activities of the crude methanolic extract and different fractions of the <i><span style="font-family:Verdana;">Epilobium</span></i> <i><span style="font-family:Verdana;">roseum</span></i> <span style="font-family:Verdana;">(Schreb). The extract and fractions were used against pathogenic bacteria (</span><i><span style="font-family:Verdana;">Bacillus</span></i> <i><span style="font-family:Verdana;">subtilis</span></i><span style="font-family:Verdana;">, </span><i><span style="font-family:Verdana;">Bacillus</span></i> <i><span style="font-family:Verdana;">atrophaeus,</span></i> <i><span style="font-family:Verdana;">Klebsiella</span></i> <i><span style="font-family:Verdana;">pneumonia</span></i> <span style="font-family:Verdana;">and </span><i><span style="font-family:Verdana;">Pseudomonas</span></i> <i><span style="font-family:Verdana;">aeruginosa</span></i><span style="font-family:Verdana;">) and fungal strains (</span><i><span style="font-family:Verdana;">Aspergillus</span></i> <i><span style="font-family:Verdana;">niger</span></i><span style="font-family:Verdana;"> and </span><i><span style="font-family:Verdana;">Aspergillus</span></i> <i><span style="font-family:Verdana;">flavus</span></i><span style="font-family:Verdana;">). The methanolic extract and their sub fraction n-hexane showed a prominent inhibition zone against all bacterial strains but inactive against fungal strains. </span><span style="font-family:Verdana;">The various extracts of </span><i><span style="font-family:Verdana;">Epilobium</span></i> <i><span style="font-family:Verdana;">roseum</span></i> <span style="font-family:Verdana;">(Schreb) from various parts were tested for their antioxidant activity by</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">1,1-Diphenyl-2-picryl-hydrazyl (DPPH) assay</span><span style="font-family:;" "=""><span style="font-family:Verdana;">. The IC</span><b><sub><span style="font-family:Verdana;font-size:12px;">50</span></sub></b><span style="font-family:Verdana;"> of the stem and root of methanolic extract and their sub fraction n-hexane showed best activity ranged between 22.73 ± 6.92, 21.49 ± 6.26 and 14.94 ± 3.54, 13.92 ± 1.04 μg/ml compared to another fraction. The results support that </span><i><span style="font-family:Verdana;">Epilobium</span></i> <i><span style="font-family:Verdana;">roseum</span></i> <span style="font-family:Verdana;">can be used as antimicrobial and antioxidant agents. The results support the present study that </span><i><span style="font-family:Verdana;">Epilobium</span></i> <i><span style="font-family:Verdana;">roseum</span></i> <span style="font-family:Verdana;">(Schreb) has a potential source of natural antibacterial, antifungal and antioxidant potentials.</span></span>展开更多
The objective of this study was to considere as an explorer for in vivo studies on the production of some secondary metabolites from local medical plants named Viola odorata. Viola odorata commonly known as “garden v...The objective of this study was to considere as an explorer for in vivo studies on the production of some secondary metabolites from local medical plants named Viola odorata. Viola odorata commonly known as “garden violet or sweet violet” belongs to family Violaceae, is a slow growing perennial, with stout rootstock, grows in hedgerows, rough land and margins of woodland. 200 mg/kg of methanol extract for V. odorata was interacted with methotrexate as a drug in albino mice to see the healing capacity for this extract. Different organs were used such as intestine, kidney, spleen, and testes for this experiment. Each organ response was recorded in this experiment. Histopathological section in the intestine of animal treated with MTX and plant showed hypertrophy and hyperplasia of goblet cells and increased cellularity of lamna properia while Histopathological section in the testes of animal treated with MTX and plant showed no sperm in the seminiferous tubules of epididymis with the round multi-nuclei cell in the lumen accompanied by homogeneous material and cellular debris while Histopathological section in the spleen of animal treated with MTX and plant proliferation of lymphocytes in the periarteriolar sheath and proliferation of mononuclear cells around sinus in red pulp and Histopathological section in the kidney of animal treated with MTX and plant mononuclear cells aggregation in the interstitial tissue mainly around blood vessels and in the adipose tissue and renal tubules. Other sections showed hydropic degeneration of renal tubules.展开更多
Sickle cell disease (SCD) is a genetic blood disorder that affects the shape and transportation of red blood cells (RBCs) in blood vessels, leading to various clinical complications. Sickle cell disease is a widesprea...Sickle cell disease (SCD) is a genetic blood disorder that affects the shape and transportation of red blood cells (RBCs) in blood vessels, leading to various clinical complications. Sickle cell disease is a widespread genetic disease in Black Africa. The objective of this study was to evaluate the sickling inhibition activity of Griffonia simplicifolia. Quantitative and qualitative tests were used to determine the major groups of secondary metabolites present in the Griffonia simplicifolia leaves extracts and the modified Emmel test was used to perform the study of sickling inhibition activity. The OECD 423 toxicity study showed that at a single dose of 2000 mg/kg bw, Griffonia simplicifolia leaves extracts are not toxic. All tested substances inhibit erythrocyte falciformation in a dose-dependent manner. The percentages of inhibition were 50.35%, 73% and 94.23% for aqueous extract, hydromethanolic extract and phenylalanine respectively at the concentration of 15 mg/mL. The methanolic extract (70%) had higher activity compared to the aqueous extract. These results suggest that the Griffonia simplicifolia extracts have some potential to be used as alternative antisickling therapy in SCD management.展开更多
Phytochemical components have been reported for various plants but very little information on Psorospermum febrifugum(SPACH).The presence of biocidal activity makes the spach of potential interest for the control of m...Phytochemical components have been reported for various plants but very little information on Psorospermum febrifugum(SPACH).The presence of biocidal activity makes the spach of potential interest for the control of micro-organisms.Methanolic extract of the leaves of spach shows the various constituents(alkaloids,flavonoids,terpenoids,tannins,phenols,and steroids).Further investigation revealed phytoconstituents of methanolic leaf extract using gas chromatography-spectrophotometric techniques(GC-MS).Result of GC-MS analysis revealed the presence of eight(8)botanical pesticides with valuable biological activities.The GC-MS results revealed that eight(8)biocidal activities were present in spach namely:1,2,3,4-tetrachloronaphtalene,Permetrin-a,permetrin-b,cyfluthrin-b,cypermethrin-a,cypermethrin-c,and flumethrin-b.The result clearly shows that Psorospermum febrifugum hold phytocomponents species of botanical interest that could still be exploited.展开更多
Objective:To evaluate in vitro antimicrobial and antioxidant activities of methanolic extract of Jasminum humile（J.humile） leaves extract.Method:Methanolic extract of J.humile was evaluated for its antimicrobial act...Objective:To evaluate in vitro antimicrobial and antioxidant activities of methanolic extract of Jasminum humile（J.humile） leaves extract.Method:Methanolic extract of J.humile was evaluated for its antimicrobial activity by using agar well diffusion method & their possible antioxidant assay by two complementary test systems,namely DPPH and hydrogen peroxide scavenging activity.These various antioxidant activities were compared to standard antioxidants such as ascorbic acid for both the tests.Results:In the DPPH & hydrogen peroxide scavenging activity,the IC<sub>50</sub> value of methanol extract was 70.43μg/mL & 60.79μg/mL respectively. Further,the extract showed inhibitory activity for Gram-positive and negative bacteria at different concentrations.The maximum antibacterial activity of extract was exhibited against Staphylococcus aureus（S.aureus） at concentration 50 mg/mL when compared with ciprofloxacin Conclusions:These results clearly indicate that J.humile is effective in scavenging free radicals and has the potential to be a powerful antioxidant.Thus,the results obtained in the present study indicate that J.humile leaves extract could be considered as a potential source of natural antioxidants and that could be used as an effective source against bacterial diseases.展开更多
Some medicinal plants are used traditionally in Saudi Arabia to treat many bacterial infections. Three plants, lemongrass (Oymbopogon citrates), lantana (Lantana cama-ra), and wild olive leaves (Olea europaea) were co...Some medicinal plants are used traditionally in Saudi Arabia to treat many bacterial infections. Three plants, lemongrass (Oymbopogon citrates), lantana (Lantana cama-ra), and wild olive leaves (Olea europaea) were collected, identified, extracted with either hot water or organic solvents (methanol, diethyl ether, ethyl acetate and n-butanol) to investigate their antibacterial activities against E. coli. The methanol ex-tracts of lemongrass, lantana and olive showed the highest activities against Esherichia coil while aqueous extract exhibited the lowest activities. Thus, the antibacterial activities of the methanolic extract of the three tested plants were determined using agar well diffusion method against some bacterial pathogens, isolated from urine samples. The highest antibacterial activity was recorded for themethanolic extract of lemongrass against all tested bacteria, E. coli, K. pneumoniae, P. aeuroginosa, P. mirabilis, E. faecalis and S. aureus. The tested bacteria differed with regard to their susceptibility to plant extracts. Lemongrass was the most active extract followed by lantana and wild olive extracts. Minimal inhibitory concentrations (MICs) of the methanolic extract of Lemongrass and some used antibiotics, Erythromycin, Tetracycline, Amoxicillin, Ciprofloxacin and Chloramphenicol were determined usingfluorescein diacetate method. Synergistic effect of the methanolic extract of lemongrass with the previous antibiotics against the tested clinical bacterial isolates was determined and the Fractional inhibitory concentrations (FIC) of different combination of the extract and the antibiotics were determined. FIC index (FICI) was calculated and it was ranged from 0.08 - 0.98. The interaction between the tested plant extract and the tested antibiotics was either synergistic or additive effects and no antagonistic effect was recorded. In conclusion, methanolic extract of lemongrass singly or in combination with some antibiotics can be used to treat pathogenic bacteria that cause urinary tract infections.展开更多
Achillea millefolium （Asteraceae） is a permanent herb highly recognized in traditional medicine for its anti-oxidant and anti-inflammation properties. However, studies on phytochemical constituents of A. millefoli...Achillea millefolium （Asteraceae） is a permanent herb highly recognized in traditional medicine for its anti-oxidant and anti-inflammation properties. However, studies on phytochemical constituents of A. millefolium underlying these properties are scarce. The present work focuses on examining the effect of methanol extract of A. millefolium L. on total and differential blood cells account on albino male mice. The results showed the methanol extract increased the account of lymphocyte, and monocyte cells, and total account as well as this extract showed high decrease in the oxidative stress of MTX after the interfere between the extract and MTX due to increase in the leucocyte cells compared with controls. Concluded from these results that methanol extract of A. millefolium has ability enhancement in leucocyte cells in the blood and it has detoxification effect of MTX.展开更多
Objective:To evaluate the analgesic,anti-inflammatory and antipyretic activity of methanolic Tecomaria capensis(T.capensis) leaves extract using different models in rats.Methods: Methanolic T.capenssis leaves extract(...Objective:To evaluate the analgesic,anti-inflammatory and antipyretic activity of methanolic Tecomaria capensis(T.capensis) leaves extract using different models in rats.Methods: Methanolic T.capenssis leaves extract(100,300,1000 and 2000 mg/kg body weight) was given to rats orally to observe acute toxicity,and observed for 14 days.Analgesic activity was evaluated using tail immersion and formalin induced paw licking models in rats.Anti-inflammatory activity was evaluated using carrageenan induced paw edema model in rats.Antipyretic activity was evaluated using brewer's yeast induced pyrexia model in rats.Methanolic T.capensis leaves extract were given at dose of 100,200 and 500 mg/kg p.o.Results:Results demonstrated that the no mortality was reported even after 14 days.This indicated that the methanol extract was safe up to a single dose of 2000 mg/kg body weight Methanolic 71 capensis leaves extract(100,200 and 500 mg/kg p.o.) significantly increased the latency period in the tail immersion test,reduced the licking time in both the neurogenic and inflammatory phases in the formalin test.Methanolic T.capensis leaves extract(100,200 and 500 mg/kg p.o.) significantly prevented increase in volume of paw edema. Methanolic 7.capensis leaves extract at the doses of(100,200 and 500 mg/kg p.o.) significantly decreased the rectal temperature of the rats.Conclusions:This study exhibites that methanolic T. capensis leaves extract possesses analgesic,anti-inflammatory and antipyretic activity which may be mediated by the central and peripheral mechanisms.展开更多
The pursuit of alternative fuel generation technologies has gained momentum due to the diminishing reserves of fossil fuels and global warming from increased CO_(2)emission.Among the proposed methods,the hydrogenation...The pursuit of alternative fuel generation technologies has gained momentum due to the diminishing reserves of fossil fuels and global warming from increased CO_(2)emission.Among the proposed methods,the hydrogenation of CO_(2)to produce marketable carbon-based products like methanol and ethanol is a practical approach that offers great potential to reduce CO_(2)emissions.Although significant volumes of methanol are currently produced from CO_(2),developing highly efficient and stable catalysts is crucial for further enhancing conversion and selectivity,thereby reducing process costs.An in-depth examination of the differences and similarities in the reaction pathways for methanol and ethanol production highlights the key factors that drive C-C coupling.Identifying these factors guides us toward developing more effective catalysts for ethanol synthesis.In this paper,we explore how different catalysts,through the production of various intermediates,can initiate the synthesis of methanol or ethanol.The catalytic mechanisms proposed by spectroscopic techniques and theoretical calculations,including operando X-ray methods,FTIR analysis,and DFT calculations,are summarized and presented.The following discussion explores the structural properties and composition of catalysts that influence C-C coupling and optimize the conversion rate of CO_(2)into ethanol.Lastly,the review examines recent catalysts employed for selective methanol and ethanol production,focusing on single-atom catalysts.展开更多
As one of the most important industrially viable methods for carbon dioxide(CO_(2))utilization,methanol synthesis serves as a platform for production of green fuels and commodity chemicals.For sustainable methanol syn...As one of the most important industrially viable methods for carbon dioxide(CO_(2))utilization,methanol synthesis serves as a platform for production of green fuels and commodity chemicals.For sustainable methanol synthesis,In_(2)O_(3)is an ideal catalyst and has garnered significant attention.Herein,cubic In_(2)O_(3)nanoparticles were prepared via the precipitation method and evaluated for CO_(2)hydrogenation to produce methanol.During the initial 10 h of reaction,CO_(2)conversion gradually increased,accompanied by a slow decrease of methanol selectivity,and the reaction reached equilibrium after 10-20 h on stream.This activation and induction stage may be attributed to the sintering of In_(2)O_(3)nanoparticles and the creation of more oxygen vacancies on In_(2)O_(3)surfaces.Further experimental studies demonstrate that hydrogen induction created additional oxygen vacancies during the catalyst activation stage,enhancing the performance of In_(2)O_(3)catalyst for CO_(2)hydrogenation.Density functional theory calculations and microkinetic simulations further demonstrated that surfaces with higher oxygen vacancy coverages or hydroxylated surfaces formed during this induction period can enhance the reaction rate and increase the CO_(2)conversion.However,they predominantly promote the formation of CO instead of methanol,leading to reduced methanol selectivity.These predictions align well with the above-mentioned experimental observations.Our work thus provides an in-depth analysis of the induction stage of the CO_(2)hydrogenation process on In_(2)O_(3)nano-catalyst,and offers valuable insights for significantly improving the CO_(2)reactivity of In_(2)O_(3)-based catalysts while maintaining long-term stability.展开更多
Cu/ZnO-based catalysts are widely employed for methanol synthesis via CO_(2) hydrogenation.The preparation procedure is sensitive to the particle size and interfacial structure,which are considered as potential active...Cu/ZnO-based catalysts are widely employed for methanol synthesis via CO_(2) hydrogenation.The preparation procedure is sensitive to the particle size and interfacial structure,which are considered as potential active centers influencing the rate of both methanol and CO formation.The particle size and the interaction between Cu and the support materials are influenced by the coprecipitation conditions,let alone that the mechanistic divergence remains unclear.In this work,a series of Cu/ZnO/ZrO_(2) catalysts were prepared via co-precipitation at different pH value and systematically characterized.The structure has been correlated with kinetic results to establish the structure-performance relationship.Kinetic analysis demonstrates that methanol synthesis follows a single-site Langmuir-Hinshelwood(L-H)mechanism,i.e.,Cu serves as the active site where CO_(2) and H_(2) competitively adsorb and react to form methanol.In contrast,CO formation proceeds via a dual-site L-H mechanism,where CO_(2) adsorbs onto ZnO and H_(2) onto Cu,with the reaction occurring at the Cu/ZnO interface.Therefore,for the direct formation of methanol,solely reducing the particle size of Cu would not be beneficial.展开更多
This work investigates the potential of low-pressure,medium-speed dual-fuel engines for cleaner maritime transportation.The thermodynamic performance of these engines is explored using three alternative fuels:liquefie...This work investigates the potential of low-pressure,medium-speed dual-fuel engines for cleaner maritime transportation.The thermodynamic performance of these engines is explored using three alternative fuels:liquefied natural gas(LNG),methanol,and ammonia.A parametric analysis examines the effect of adjustments to key engine parameters(compression ratio,boost pressure,and air-fuel ratio)on performance.Results show an initial improvement in performance with an increase in compression ratio,which reaches a peak and then declines.Similarly,increases in boost pressure and air-fuel ratio lead to linear performance gains.However,insufficient cooling reduces the amount of fuel burned,which hinders performance.Exergy analysis reveals significant exergy destruction within the engine,which ranges from 69.96%(methanol)to 78.48%(LNG).Notably,the combustion process is the leading cause of exergy loss.Among the fuels tested,methanol exhibits the lowest combustion-related exergy destruction(56.41%),followed by ammonia(62.12%)and LNG(73.77%).These findings suggest that methanol is a promising near-term alternative to LNG for marine fuel applications.展开更多
文摘BACKGROUND The investigation of plant-based therapeutic agents in medicinal plants has revealed their presence in the extracts and provides the vision to formulate novel techniques for drug therapy.Vitex negundo(V.negundo),a perennial herb belonging to the Varbanaceae family,is extensively used in conventional medication.AIM To determine the existence of therapeutic components in leaf and callus extracts from wild V.negundo plants using gas chromatography-mass spectrometry(GCMS).METHODS In this study,we conducted GC-MS on wild plant leaf extracts and correlated the presence of constituents with those in callus extracts.Various growth regulators such as 6-benzylaminopurine(BAP),2,4-dichlorophenoxyacetic acid(2,4-D),α-naphthylacetic acid(NAA),and di-phenylurea(DPU)were added to plant leaves and in-vitro callus and grown on MS medium.RESULTS The results clearly indicated that the addition of BAP(2.0 mg/L),2,4-D(0.2 mg/mL),DPU(2.0 mg/L)and 2,4-D(0.2 mg/mL)in MS medium resulted in rapid callus development.The plant profile of Vitex extracts by GC-MS analysis showed that 24,10,and 14 bioactive constituents were detected in the methanolic extract of leaf,green callus and the methanolic extract of white loose callus,respectively.CONCLUSION Octadecadienoic acid,hexadecanoic acid and methyl ester were the major constituents in the leaf and callus methanolic extract.Octadecadienoic acid was the most common constituent in all samples.The maximum concentration of octadecadienoic acid in leaves,green callus and white loose callus was 21.93%,47.79%and 40.38%,respectively.These findings demonstrate that the concentration of octadecadienoic acid doubles in-vitro compared to in-vivo.In addition to octadecadienoic acid;butyric acid,benzene,1-methoxy-4-(1-propenyl),dospan,tridecanedialdehyde,methylcyclohexenylbutanol,chlorpyrifos,n-secondary terpene diester,anflunine and other important active compounds were also detected.All these components were only available in callus formed in-vitro.This study showed that the callus contained additional botanical characteristics compared with wild plants.Due to the presence of numerous bioactive compounds,the medical use of Vitex for various diseases has been accepted and the plant is considered an important source of therapeutics for research and development.
文摘Objective:To evaluate the antidiabetic potential of methanolic extract of Albizia odoratissima Benth.bark in alloxan induced diabetic mice.Methods:Group-Ⅰ(normal control) mice received only basal diet without any treatment.In Group-Ⅱ(Diabetic control) mice,diabetes was induced by alloxan(150 mg/kg i.p.) and received only Tween 80.5%v/v in normal saline. Group-Ⅲand Group-Ⅳmice received metformin(10 mg/kg) and gliclazide(10 mg/kg) as standard drugs.Group-ⅤandⅥmice received methanolic bark extract of Albizia odoratissima at doses of 250 and 500 mg/kg body weight p.o.,respectively.Results:The results of the study indicates that Albizia odoratissima bark extract significantly(P【0.01) reduced the blood sugar level.The bark extract also significantly reduced the levels of serum cholesterol,triglycerides, serum glutamic-oxaloacetic transaminase,serum glutamic-pyruvic transaminase,alkaline phosphatase and decreases level of total proteins in alloxan induced diabetic mice.Conclusions: Methanolic extract of Albizia odoratissima has protective effects on the protection of vital tissues(pancreas,kidney,liver,heart and spleen),thereby reducing the causation of diabetes in experimental animals.
文摘Objective: To evaluate the effects of methanol root extract of Mahonia leschenaultii and berberine of Mahonia leschenaultii on Dalton’s ascitic lymphoma in Swiss Albino mice. Methods: The methanol root extracts of Mahonia leschenaultii(200 and 400 mg/kg) were given orally, and berberines(10 and 20 mg/kg) were injected intra-peritoneally for 14 successive days in tumor bearing mice. Hematological parameters(white and red blood cells, haemoglobin level, granulocytes, and agranulocytes), lipid parameters(total cholesterol and triglycerides), serum enzymes(serum glutamate pyruvate transaminases, serum glutamate oxaloacetate transaminases, and alkaline phosphatise) and mean survival and solid tumor growth were determined and compared with untreated mice. 5-fluorouracil(20 mg/kg) was used as a reference standard drug. Results: Mahonia leschenaultii and berberine reduced the hematocrit significantly. Furthermore, Mahonia leschenaultii and berberine improved the survival of mice significantly and restored the affected hematological and lipid parameters similar to the normal levels. Conclusions: These observations show a strong anticancer effect of methanol root extract of Mahonia leschenaultii and berberine in suppressing Dalton’s ascitic lymphoma cancer cell growth in a mouse model by controlling haematological, lipid, serum enzymes, and other derived parameters effectively.
文摘A bacterial field isolate recovered from infected tomato plants in a green-house at Sidi Rehal, a region near Casablanca city (Morocco), was identified as the gammaproteobacterium Pseudomonas syringae pv. tomato DC3000 strain, the causal agent of bacterial speck. The bacterial isolate was characterized by morphological, biochemical and molecular biological tests, its growth curves carried out in various culture media, and its phytopathogenicity verified by infection tests. A screening was performed to evaluate the antibacterial activity of methanolic extracts of 12 selected Moroccan plants against the P. syringae pv. tomato DC3000 isolate, and Agar-well diffusion and Broth microdilution methods were used to determine minimum inhibitory and minimum bactericidal concentrations. Among the methanolic extracts tested, only those of Nigella sativa, Geranuim robertianum, Aizoon canariense and Rubia peregrine showed clear inhibitory and bactericidal activities, although the highest values were achieved with N. sativa, a plant used in Morocco as a spice, condiment and medicinal treatment.
文摘Objective:Acorus calamus(AC)L.(Araceae)is an annual semi-aquatic and aromatic plant found in Europe,North America and Asia.Its rhizomes are often used by Native Americans,Americans,and Chinese as well as by other cultures.Ethnobotanical studies and documents have shown their use in various disease treatments,such as insomnia,mental disorders,diabetes mellitus,epilepsy,inflammation,asthma,neuropathic pain,and diarrhea.In this study,the antidepressant activity of methanolic and hydroalcoholic extracts of the AC rhizome part in mice was investigated.Methods:Three doses of methanolic extract of AC rhizome(MEACR)(25,50 and 100 mg/kg b.wt),three doses of hydroalcoholic extract of AC rhizome(HAACR)(100,200 and 400 mg/kg b.wt),and standards(imipramine,15 mg/kg b.wt and fluoxetine,20 mg/kg b.wt)was daily oral administration to the mice for consecutive 14 days.The extract effect on the immobility time was monitored by a tail suspension test(TST)and a forced swimming test(FST).Monoamine oxidase(MAO)levels were also analyzed using standard methods.Results:The optimum antidepressant activity was viewed at 100 mg/kg b.wt of MEACR extract and400 mg/kg b.wt of HAACR extract with 23.82%and 20.59%immobility period reduction,respectively.Besides,the extracts weakened the FST-induced elevation of MAO activity significantly and returned to near-normal levels of neurotransmitters in the brain.100 mg/kg b.wt or above of MEACR extract significantly prevented the MAO-A and MAO-B activities in mice brain at a dose-dependent fashion.But,just 400 mg/kg b.wt of HAACR extract prevented the activity of MAO-A and MAO-B.Fluoxetine and imipramine showed a tendency to prevent the activity of MAO-A and MAO-B.Conclusion:This study suggests that AC rhizome extract mediated antidepressant activity by modulating the central neurochemical and hypothalamic-pituitary-adrenal(HPA)axis in response to FST and TSTinduced stress.Therefore,AC rhizome extract can be used as a valuable plant supplement to treat depressive disorders.
文摘The current study was carried out to determine the bioactivity of P. lentiscus leaf extracts as potential antibacterial and antioxidant properties. The plant extracts were examined for antibacterial activity against antibiotic-resistant Staphylococcus aureus, Staphylococcus haemolyticus, Pseudomonas aeruginosa, and Proteus mirabilis using the agar well method (according to the guidelines of Clinical and Laboratory Standard Institute). The antioxidant potential of 3 plant leaf extracts was determined by their ability to convert Fe<sup>3+</sup> to Fe<sup>2+</sup> and scavenge the DPPH free radical. At all concentrations studied, the methanolic leaf extract had higher total phenolic and flavonoid content, as well as stronger antioxidant and antibacterial inhibitory activity compared to aqueous extract. Our findings with P. aeruginosa were especially interesting, because this bacterium was inhibited by methanol extract than that of the reference antibiotics. The results also demonstrated a link between DPPH radical scavenging ability, reducing power, and total phenolic and flavonoid content of plant extracts (r > 0.97, R<sup>2</sup> > 0.95, P = 0.01). As a result, the methanolic leaf extract of the chosen plant might be employed as an effective antioxidant and antibacterial agent for the treatment of a variety of morbidities.
基金supported by the National Natural Science Foundation of China(Nos.21572015,21877007,81703540 and 21702007)China Postdoctoral Science Foundation(No.2018M631796)+2 种基金Technology Plan Foundation of Liaoning Province(No.20170520063)Chinese Medicine Related Scientific Research Project of Dalian(No.17Z2013)the open funding of the State Key Laboratory of Phytochemistry and Plant Resources in West China。
文摘The acetyl ester plays an important role for protection of the hydroxyl groups in carbohydrates synthesis.In the present study,we described an efficient deprotection of acetyl group of pentacyclic triterpenoid by using methanolic ammonia in THF solution.Good selectivity for cleaving gal-C2-OAc group of 3β-hydroxy-olean-12-en-28-oic acid 28-N-2,3,4,6-tetra-O-acetyl-β-D-galactopyranoside(3) was achieved in the presence of methanolic ammonia within 4 h at low temperature(-60℃) in a yield of 56%.The reaction disclosed here provides a new method for the synthesis of C2 selective modified carbohydrates,which is more useful than conventional synthesis procedure that usually requires many steps including temporary regioselective protection and deprotection.When the reaction temperature was increased from -60℃ to room temperature,the cleavage of the other three acetyl groups of galactose in an order of C4-OAc>C3-OAc>C6-OAc was observed.Based on this study,a plausible route for the deacetylation reaction has been proposed.
文摘This present study was aimed to investigate the antidiabetic and antihyperlipidemic activities of methanolic leaf extract (LE) of Stephania japonica alone and in combination with metformin in alloxan induced diabetic rats. Primarily acute toxicity study and oral glucose tolerance test were performed. Diabetes was confirmed after 12 days of single intraperitoneal injection of alloxan (120 mg/kg BW) in albino male rats. Rats were divided into six groups’;normal control (Group I) and diabetic induced groups as (Group II, III, IV, V and VI). Group III & IV were treated with leaf extract of S. japonica (200 mg/kg BW & 350 mg/kg BW). Group V (Met 850 mg/70 kg BW) and group VI: (combination of Met 425 mg/70 kg BW and LE 250 mg/kg BW) for four weeks. Body weight of each rat in the different groups was recorded at 0, 7th, 14th, 21st and 28th day of treatment. TC, TG, LDL-C and HDL-C were measured analytically after 28 days of treatment. Alloxan induction also caused left ventricular hypertrophy. LE of S. Japonica showed a good result in OGTT. Oral treatment of different doses of LE and combination therapy reduced elevated level of BG, TC, TG, LDL-C and increased HDL-C level significantly (p S. japonica (Thunb.) Miers showed antihyperlipidemic and antidiabetic effect and hence could be suggested as a potential therapeutic agent for diabetic treatment.
文摘Present study aims to evaluate antimicrobial and antioxidant activities of the crude methanolic extract and different fractions of the <i><span style="font-family:Verdana;">Epilobium</span></i> <i><span style="font-family:Verdana;">roseum</span></i> <span style="font-family:Verdana;">(Schreb). The extract and fractions were used against pathogenic bacteria (</span><i><span style="font-family:Verdana;">Bacillus</span></i> <i><span style="font-family:Verdana;">subtilis</span></i><span style="font-family:Verdana;">, </span><i><span style="font-family:Verdana;">Bacillus</span></i> <i><span style="font-family:Verdana;">atrophaeus,</span></i> <i><span style="font-family:Verdana;">Klebsiella</span></i> <i><span style="font-family:Verdana;">pneumonia</span></i> <span style="font-family:Verdana;">and </span><i><span style="font-family:Verdana;">Pseudomonas</span></i> <i><span style="font-family:Verdana;">aeruginosa</span></i><span style="font-family:Verdana;">) and fungal strains (</span><i><span style="font-family:Verdana;">Aspergillus</span></i> <i><span style="font-family:Verdana;">niger</span></i><span style="font-family:Verdana;"> and </span><i><span style="font-family:Verdana;">Aspergillus</span></i> <i><span style="font-family:Verdana;">flavus</span></i><span style="font-family:Verdana;">). The methanolic extract and their sub fraction n-hexane showed a prominent inhibition zone against all bacterial strains but inactive against fungal strains. </span><span style="font-family:Verdana;">The various extracts of </span><i><span style="font-family:Verdana;">Epilobium</span></i> <i><span style="font-family:Verdana;">roseum</span></i> <span style="font-family:Verdana;">(Schreb) from various parts were tested for their antioxidant activity by</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">1,1-Diphenyl-2-picryl-hydrazyl (DPPH) assay</span><span style="font-family:;" "=""><span style="font-family:Verdana;">. The IC</span><b><sub><span style="font-family:Verdana;font-size:12px;">50</span></sub></b><span style="font-family:Verdana;"> of the stem and root of methanolic extract and their sub fraction n-hexane showed best activity ranged between 22.73 ± 6.92, 21.49 ± 6.26 and 14.94 ± 3.54, 13.92 ± 1.04 μg/ml compared to another fraction. The results support that </span><i><span style="font-family:Verdana;">Epilobium</span></i> <i><span style="font-family:Verdana;">roseum</span></i> <span style="font-family:Verdana;">can be used as antimicrobial and antioxidant agents. The results support the present study that </span><i><span style="font-family:Verdana;">Epilobium</span></i> <i><span style="font-family:Verdana;">roseum</span></i> <span style="font-family:Verdana;">(Schreb) has a potential source of natural antibacterial, antifungal and antioxidant potentials.</span></span>
文摘The objective of this study was to considere as an explorer for in vivo studies on the production of some secondary metabolites from local medical plants named Viola odorata. Viola odorata commonly known as “garden violet or sweet violet” belongs to family Violaceae, is a slow growing perennial, with stout rootstock, grows in hedgerows, rough land and margins of woodland. 200 mg/kg of methanol extract for V. odorata was interacted with methotrexate as a drug in albino mice to see the healing capacity for this extract. Different organs were used such as intestine, kidney, spleen, and testes for this experiment. Each organ response was recorded in this experiment. Histopathological section in the intestine of animal treated with MTX and plant showed hypertrophy and hyperplasia of goblet cells and increased cellularity of lamna properia while Histopathological section in the testes of animal treated with MTX and plant showed no sperm in the seminiferous tubules of epididymis with the round multi-nuclei cell in the lumen accompanied by homogeneous material and cellular debris while Histopathological section in the spleen of animal treated with MTX and plant proliferation of lymphocytes in the periarteriolar sheath and proliferation of mononuclear cells around sinus in red pulp and Histopathological section in the kidney of animal treated with MTX and plant mononuclear cells aggregation in the interstitial tissue mainly around blood vessels and in the adipose tissue and renal tubules. Other sections showed hydropic degeneration of renal tubules.
文摘Sickle cell disease (SCD) is a genetic blood disorder that affects the shape and transportation of red blood cells (RBCs) in blood vessels, leading to various clinical complications. Sickle cell disease is a widespread genetic disease in Black Africa. The objective of this study was to evaluate the sickling inhibition activity of Griffonia simplicifolia. Quantitative and qualitative tests were used to determine the major groups of secondary metabolites present in the Griffonia simplicifolia leaves extracts and the modified Emmel test was used to perform the study of sickling inhibition activity. The OECD 423 toxicity study showed that at a single dose of 2000 mg/kg bw, Griffonia simplicifolia leaves extracts are not toxic. All tested substances inhibit erythrocyte falciformation in a dose-dependent manner. The percentages of inhibition were 50.35%, 73% and 94.23% for aqueous extract, hydromethanolic extract and phenylalanine respectively at the concentration of 15 mg/mL. The methanolic extract (70%) had higher activity compared to the aqueous extract. These results suggest that the Griffonia simplicifolia extracts have some potential to be used as alternative antisickling therapy in SCD management.
文摘Phytochemical components have been reported for various plants but very little information on Psorospermum febrifugum(SPACH).The presence of biocidal activity makes the spach of potential interest for the control of micro-organisms.Methanolic extract of the leaves of spach shows the various constituents(alkaloids,flavonoids,terpenoids,tannins,phenols,and steroids).Further investigation revealed phytoconstituents of methanolic leaf extract using gas chromatography-spectrophotometric techniques(GC-MS).Result of GC-MS analysis revealed the presence of eight(8)botanical pesticides with valuable biological activities.The GC-MS results revealed that eight(8)biocidal activities were present in spach namely:1,2,3,4-tetrachloronaphtalene,Permetrin-a,permetrin-b,cyfluthrin-b,cypermethrin-a,cypermethrin-c,and flumethrin-b.The result clearly shows that Psorospermum febrifugum hold phytocomponents species of botanical interest that could still be exploited.
文摘Objective:To evaluate in vitro antimicrobial and antioxidant activities of methanolic extract of Jasminum humile（J.humile） leaves extract.Method:Methanolic extract of J.humile was evaluated for its antimicrobial activity by using agar well diffusion method & their possible antioxidant assay by two complementary test systems,namely DPPH and hydrogen peroxide scavenging activity.These various antioxidant activities were compared to standard antioxidants such as ascorbic acid for both the tests.Results:In the DPPH & hydrogen peroxide scavenging activity,the IC<sub>50</sub> value of methanol extract was 70.43μg/mL & 60.79μg/mL respectively. Further,the extract showed inhibitory activity for Gram-positive and negative bacteria at different concentrations.The maximum antibacterial activity of extract was exhibited against Staphylococcus aureus（S.aureus） at concentration 50 mg/mL when compared with ciprofloxacin Conclusions:These results clearly indicate that J.humile is effective in scavenging free radicals and has the potential to be a powerful antioxidant.Thus,the results obtained in the present study indicate that J.humile leaves extract could be considered as a potential source of natural antioxidants and that could be used as an effective source against bacterial diseases.
文摘Some medicinal plants are used traditionally in Saudi Arabia to treat many bacterial infections. Three plants, lemongrass (Oymbopogon citrates), lantana (Lantana cama-ra), and wild olive leaves (Olea europaea) were collected, identified, extracted with either hot water or organic solvents (methanol, diethyl ether, ethyl acetate and n-butanol) to investigate their antibacterial activities against E. coli. The methanol ex-tracts of lemongrass, lantana and olive showed the highest activities against Esherichia coil while aqueous extract exhibited the lowest activities. Thus, the antibacterial activities of the methanolic extract of the three tested plants were determined using agar well diffusion method against some bacterial pathogens, isolated from urine samples. The highest antibacterial activity was recorded for themethanolic extract of lemongrass against all tested bacteria, E. coli, K. pneumoniae, P. aeuroginosa, P. mirabilis, E. faecalis and S. aureus. The tested bacteria differed with regard to their susceptibility to plant extracts. Lemongrass was the most active extract followed by lantana and wild olive extracts. Minimal inhibitory concentrations (MICs) of the methanolic extract of Lemongrass and some used antibiotics, Erythromycin, Tetracycline, Amoxicillin, Ciprofloxacin and Chloramphenicol were determined usingfluorescein diacetate method. Synergistic effect of the methanolic extract of lemongrass with the previous antibiotics against the tested clinical bacterial isolates was determined and the Fractional inhibitory concentrations (FIC) of different combination of the extract and the antibiotics were determined. FIC index (FICI) was calculated and it was ranged from 0.08 - 0.98. The interaction between the tested plant extract and the tested antibiotics was either synergistic or additive effects and no antagonistic effect was recorded. In conclusion, methanolic extract of lemongrass singly or in combination with some antibiotics can be used to treat pathogenic bacteria that cause urinary tract infections.
文摘Achillea millefolium （Asteraceae） is a permanent herb highly recognized in traditional medicine for its anti-oxidant and anti-inflammation properties. However, studies on phytochemical constituents of A. millefolium underlying these properties are scarce. The present work focuses on examining the effect of methanol extract of A. millefolium L. on total and differential blood cells account on albino male mice. The results showed the methanol extract increased the account of lymphocyte, and monocyte cells, and total account as well as this extract showed high decrease in the oxidative stress of MTX after the interfere between the extract and MTX due to increase in the leucocyte cells compared with controls. Concluded from these results that methanol extract of A. millefolium has ability enhancement in leucocyte cells in the blood and it has detoxification effect of MTX.
基金supported by management ofJaipur National University,Jaipur,India
文摘Objective:To evaluate the analgesic,anti-inflammatory and antipyretic activity of methanolic Tecomaria capensis(T.capensis) leaves extract using different models in rats.Methods: Methanolic T.capenssis leaves extract(100,300,1000 and 2000 mg/kg body weight) was given to rats orally to observe acute toxicity,and observed for 14 days.Analgesic activity was evaluated using tail immersion and formalin induced paw licking models in rats.Anti-inflammatory activity was evaluated using carrageenan induced paw edema model in rats.Antipyretic activity was evaluated using brewer's yeast induced pyrexia model in rats.Methanolic T.capensis leaves extract were given at dose of 100,200 and 500 mg/kg p.o.Results:Results demonstrated that the no mortality was reported even after 14 days.This indicated that the methanol extract was safe up to a single dose of 2000 mg/kg body weight Methanolic 71 capensis leaves extract(100,200 and 500 mg/kg p.o.) significantly increased the latency period in the tail immersion test,reduced the licking time in both the neurogenic and inflammatory phases in the formalin test.Methanolic T.capensis leaves extract(100,200 and 500 mg/kg p.o.) significantly prevented increase in volume of paw edema. Methanolic 7.capensis leaves extract at the doses of(100,200 and 500 mg/kg p.o.) significantly decreased the rectal temperature of the rats.Conclusions:This study exhibites that methanolic T. capensis leaves extract possesses analgesic,anti-inflammatory and antipyretic activity which may be mediated by the central and peripheral mechanisms.
基金the Canadian NRCan OERD Energy Innovation Programthe Natural Sciences and Engineering Research Council of Canada,and the Carbon Solution Program for their financial support.
文摘The pursuit of alternative fuel generation technologies has gained momentum due to the diminishing reserves of fossil fuels and global warming from increased CO_(2)emission.Among the proposed methods,the hydrogenation of CO_(2)to produce marketable carbon-based products like methanol and ethanol is a practical approach that offers great potential to reduce CO_(2)emissions.Although significant volumes of methanol are currently produced from CO_(2),developing highly efficient and stable catalysts is crucial for further enhancing conversion and selectivity,thereby reducing process costs.An in-depth examination of the differences and similarities in the reaction pathways for methanol and ethanol production highlights the key factors that drive C-C coupling.Identifying these factors guides us toward developing more effective catalysts for ethanol synthesis.In this paper,we explore how different catalysts,through the production of various intermediates,can initiate the synthesis of methanol or ethanol.The catalytic mechanisms proposed by spectroscopic techniques and theoretical calculations,including operando X-ray methods,FTIR analysis,and DFT calculations,are summarized and presented.The following discussion explores the structural properties and composition of catalysts that influence C-C coupling and optimize the conversion rate of CO_(2)into ethanol.Lastly,the review examines recent catalysts employed for selective methanol and ethanol production,focusing on single-atom catalysts.
文摘As one of the most important industrially viable methods for carbon dioxide(CO_(2))utilization,methanol synthesis serves as a platform for production of green fuels and commodity chemicals.For sustainable methanol synthesis,In_(2)O_(3)is an ideal catalyst and has garnered significant attention.Herein,cubic In_(2)O_(3)nanoparticles were prepared via the precipitation method and evaluated for CO_(2)hydrogenation to produce methanol.During the initial 10 h of reaction,CO_(2)conversion gradually increased,accompanied by a slow decrease of methanol selectivity,and the reaction reached equilibrium after 10-20 h on stream.This activation and induction stage may be attributed to the sintering of In_(2)O_(3)nanoparticles and the creation of more oxygen vacancies on In_(2)O_(3)surfaces.Further experimental studies demonstrate that hydrogen induction created additional oxygen vacancies during the catalyst activation stage,enhancing the performance of In_(2)O_(3)catalyst for CO_(2)hydrogenation.Density functional theory calculations and microkinetic simulations further demonstrated that surfaces with higher oxygen vacancy coverages or hydroxylated surfaces formed during this induction period can enhance the reaction rate and increase the CO_(2)conversion.However,they predominantly promote the formation of CO instead of methanol,leading to reduced methanol selectivity.These predictions align well with the above-mentioned experimental observations.Our work thus provides an in-depth analysis of the induction stage of the CO_(2)hydrogenation process on In_(2)O_(3)nano-catalyst,and offers valuable insights for significantly improving the CO_(2)reactivity of In_(2)O_(3)-based catalysts while maintaining long-term stability.
基金supported by Research Grant from China Petroleum and Chemical Corp。
文摘Cu/ZnO-based catalysts are widely employed for methanol synthesis via CO_(2) hydrogenation.The preparation procedure is sensitive to the particle size and interfacial structure,which are considered as potential active centers influencing the rate of both methanol and CO formation.The particle size and the interaction between Cu and the support materials are influenced by the coprecipitation conditions,let alone that the mechanistic divergence remains unclear.In this work,a series of Cu/ZnO/ZrO_(2) catalysts were prepared via co-precipitation at different pH value and systematically characterized.The structure has been correlated with kinetic results to establish the structure-performance relationship.Kinetic analysis demonstrates that methanol synthesis follows a single-site Langmuir-Hinshelwood(L-H)mechanism,i.e.,Cu serves as the active site where CO_(2) and H_(2) competitively adsorb and react to form methanol.In contrast,CO formation proceeds via a dual-site L-H mechanism,where CO_(2) adsorbs onto ZnO and H_(2) onto Cu,with the reaction occurring at the Cu/ZnO interface.Therefore,for the direct formation of methanol,solely reducing the particle size of Cu would not be beneficial.
文摘This work investigates the potential of low-pressure,medium-speed dual-fuel engines for cleaner maritime transportation.The thermodynamic performance of these engines is explored using three alternative fuels:liquefied natural gas(LNG),methanol,and ammonia.A parametric analysis examines the effect of adjustments to key engine parameters(compression ratio,boost pressure,and air-fuel ratio)on performance.Results show an initial improvement in performance with an increase in compression ratio,which reaches a peak and then declines.Similarly,increases in boost pressure and air-fuel ratio lead to linear performance gains.However,insufficient cooling reduces the amount of fuel burned,which hinders performance.Exergy analysis reveals significant exergy destruction within the engine,which ranges from 69.96%(methanol)to 78.48%(LNG).Notably,the combustion process is the leading cause of exergy loss.Among the fuels tested,methanol exhibits the lowest combustion-related exergy destruction(56.41%),followed by ammonia(62.12%)and LNG(73.77%).These findings suggest that methanol is a promising near-term alternative to LNG for marine fuel applications.
