Effects of pH , donor phase concentration and surfactants on skin permeation in vitro were investigated using excised rat skin. Percutaneous absorption rate of dihydro etorphine hydrochloride(DHE)was increased in the ...Effects of pH , donor phase concentration and surfactants on skin permeation in vitro were investigated using excised rat skin. Percutaneous absorption rate of dihydro etorphine hydrochloride(DHE)was increased in the of pH5,pH3,pH7 and pH9.When the DHE concentration was from 20 to 80μg/ml,the permeation rate at different concentrations was ratherstable at pH 7 and9,but was intricated at pH 3 and 5.Skin penneation treated with1,propanediol,Azone,and 3% menthol in 50% ethanol solution increased the permeability of DHE by1. 16,1.95,4.86 times ,respectively.展开更多
The chemical composition of essential oils obtained from Artemisia herba-alba and Mentha pulegium were determined. The essential oils were analyzed by gas chromatography coupled with mass spectrometry （GC/MS）. Their...The chemical composition of essential oils obtained from Artemisia herba-alba and Mentha pulegium were determined. The essential oils were analyzed by gas chromatography coupled with mass spectrometry （GC/MS）. Their antibacterial activity was studied in vitro against three standard strains： E. coli ATCC 25922, Staphylococcus aureus ATCC 29213, Pseudomonas aeruginosa ATCC 27853, and five clinical strains： Enterobacter cloacae, Staphylococcus aureus, Pseudomonas pyocyanique, Enterococcus faecium, and E. coli. Nineteen constituents were identified in A. herba-alba essential oil representing 99.57% of the total composition The major component was α-thujone （59.07%）. The bacterial strains were inhibited at concentrations ranging from 1.25 μL/mL to 5μL/mL and killed at concentrations ranging from 1.25 μL/mL to 10 μL/mL. M. pulegium resulted in the identification of eighteen constituents representing 99.48% of the total composition. The main component was pulegone （78.07%）. The minimal inhibitory （MIC） and bactericidal （MBC） concentrations were ranging from 1.25 μL/mL to 2.5 μL/mL.展开更多
This study was designed to evaluate antimicrobial and antioxidant activities of the essential oil and methanol extract from Mentha longifolia L. hudson. Antioxidant activity was evaluated through 2,2-diphenyl-l-picryl...This study was designed to evaluate antimicrobial and antioxidant activities of the essential oil and methanol extract from Mentha longifolia L. hudson. Antioxidant activity was evaluated through 2,2-diphenyl-l-picrylhydrazyl （DPPH） assay and β-carotene/linoleic acid assay. The essential oil and methanol extract were individually tested [disc-diffusion assay and evaluating minimum inhibition concentration （MIC）] against a number of bacteria. The essential oil showed strong antimicrobial activity against bacteria tested whereas the methanol extract almost remained inactive. In contrast, the extract showed much better activity than the essential oil in antioxidant activity assays employed, e.g. in the inhibition of free radical DPPH and β-carotene/linolcic acid systems. In the former, the extract was able to reduce the stable free radical DPPH with an IC50 of 55.3μg/mL while that of the oils were 10,630μg/mL. When compared to BHT （butylated hydroxytoluene）, a synthetic antioxidant, both showed weaker antioxidative potential. Similarly, in β-carotene/linoleic acid assay, these samples were not effectively able to inhibit the linoleic acid oxidation; exhibiting only 24% and 36% inhibitions at 2 mg/mL, respectively; both were far below than that of BHT. Total phenolic constituent of the extract was approximately 4.5 g/100 g as gallic acid equivalent. Gas chromatography-mass spectroscopy （GC-MS） analysis of the oil resulted in the identification of 45 constituents, ei^-piperitone epoxide, pulegone and piperitenone oxide being the main components. The results indicate that essential oil and extract ofM. longifolia L. hudson may be used as natural preservative in food against the agents of foodborne diseases and food spoilage.展开更多
The search for new prototype drugs to combat infection is an absolute necessity and in this regard plant essential oils may offer great potential and hope. In this investigation, the essential oil of the leaves ofMent...The search for new prototype drugs to combat infection is an absolute necessity and in this regard plant essential oils may offer great potential and hope. In this investigation, the essential oil of the leaves ofMentha officinalis grown in Rwanda was extracted by hydrodistillation method and analyzed by gas chromatography （GC） and gas chromatography coupled with mass spectrometry （GC-MS）. The disc diffusion method was used to evaluate in vitro the zone of bacterial growth inhibition at various concentrations of the oil for five bacterial strains： Escherichia coli, Bacillus aureus, Streptococcus lactis, Staphylococcus aureus and Salmonella typhimurium. The results of this study revealed many components among which the major components were menthol （80.79%）, menthone （4.906%）, isomenthone （3.5%）, piperitone （2.56%）, and methyl acetate （2.2%）. After 7 days of incubation on PCA medium, the growth of Escherichia coli, Bacillus aureus, Streptococcus lactis and Staphylococcus aureus was totally inhibited at an average diameter of 19 mm, 32 mm, 50 mm and 30 mm respectively by a medium concentration of 30 μm/disc ofM. officinalis oil. Quite the reverse, this investigation by a bioassay showed that the essential oil ofM. officinalis has no effect on Salmonella typhimurium. The obtained results in the present study indicate the possibility of exploiting the essential oil ofM. officinalis to combat so many infectious human diseases in Rwanda. However, further investigations are required to make the medical exploitation of this plant successful.展开更多
文摘Effects of pH , donor phase concentration and surfactants on skin permeation in vitro were investigated using excised rat skin. Percutaneous absorption rate of dihydro etorphine hydrochloride(DHE)was increased in the of pH5,pH3,pH7 and pH9.When the DHE concentration was from 20 to 80μg/ml,the permeation rate at different concentrations was ratherstable at pH 7 and9,but was intricated at pH 3 and 5.Skin penneation treated with1,propanediol,Azone,and 3% menthol in 50% ethanol solution increased the permeability of DHE by1. 16,1.95,4.86 times ,respectively.
文摘The chemical composition of essential oils obtained from Artemisia herba-alba and Mentha pulegium were determined. The essential oils were analyzed by gas chromatography coupled with mass spectrometry （GC/MS）. Their antibacterial activity was studied in vitro against three standard strains： E. coli ATCC 25922, Staphylococcus aureus ATCC 29213, Pseudomonas aeruginosa ATCC 27853, and five clinical strains： Enterobacter cloacae, Staphylococcus aureus, Pseudomonas pyocyanique, Enterococcus faecium, and E. coli. Nineteen constituents were identified in A. herba-alba essential oil representing 99.57% of the total composition The major component was α-thujone （59.07%）. The bacterial strains were inhibited at concentrations ranging from 1.25 μL/mL to 5μL/mL and killed at concentrations ranging from 1.25 μL/mL to 10 μL/mL. M. pulegium resulted in the identification of eighteen constituents representing 99.48% of the total composition. The main component was pulegone （78.07%）. The minimal inhibitory （MIC） and bactericidal （MBC） concentrations were ranging from 1.25 μL/mL to 2.5 μL/mL.
文摘This study was designed to evaluate antimicrobial and antioxidant activities of the essential oil and methanol extract from Mentha longifolia L. hudson. Antioxidant activity was evaluated through 2,2-diphenyl-l-picrylhydrazyl （DPPH） assay and β-carotene/linoleic acid assay. The essential oil and methanol extract were individually tested [disc-diffusion assay and evaluating minimum inhibition concentration （MIC）] against a number of bacteria. The essential oil showed strong antimicrobial activity against bacteria tested whereas the methanol extract almost remained inactive. In contrast, the extract showed much better activity than the essential oil in antioxidant activity assays employed, e.g. in the inhibition of free radical DPPH and β-carotene/linolcic acid systems. In the former, the extract was able to reduce the stable free radical DPPH with an IC50 of 55.3μg/mL while that of the oils were 10,630μg/mL. When compared to BHT （butylated hydroxytoluene）, a synthetic antioxidant, both showed weaker antioxidative potential. Similarly, in β-carotene/linoleic acid assay, these samples were not effectively able to inhibit the linoleic acid oxidation; exhibiting only 24% and 36% inhibitions at 2 mg/mL, respectively; both were far below than that of BHT. Total phenolic constituent of the extract was approximately 4.5 g/100 g as gallic acid equivalent. Gas chromatography-mass spectroscopy （GC-MS） analysis of the oil resulted in the identification of 45 constituents, ei^-piperitone epoxide, pulegone and piperitenone oxide being the main components. The results indicate that essential oil and extract ofM. longifolia L. hudson may be used as natural preservative in food against the agents of foodborne diseases and food spoilage.
文摘The search for new prototype drugs to combat infection is an absolute necessity and in this regard plant essential oils may offer great potential and hope. In this investigation, the essential oil of the leaves ofMentha officinalis grown in Rwanda was extracted by hydrodistillation method and analyzed by gas chromatography （GC） and gas chromatography coupled with mass spectrometry （GC-MS）. The disc diffusion method was used to evaluate in vitro the zone of bacterial growth inhibition at various concentrations of the oil for five bacterial strains： Escherichia coli, Bacillus aureus, Streptococcus lactis, Staphylococcus aureus and Salmonella typhimurium. The results of this study revealed many components among which the major components were menthol （80.79%）, menthone （4.906%）, isomenthone （3.5%）, piperitone （2.56%）, and methyl acetate （2.2%）. After 7 days of incubation on PCA medium, the growth of Escherichia coli, Bacillus aureus, Streptococcus lactis and Staphylococcus aureus was totally inhibited at an average diameter of 19 mm, 32 mm, 50 mm and 30 mm respectively by a medium concentration of 30 μm/disc ofM. officinalis oil. Quite the reverse, this investigation by a bioassay showed that the essential oil ofM. officinalis has no effect on Salmonella typhimurium. The obtained results in the present study indicate the possibility of exploiting the essential oil ofM. officinalis to combat so many infectious human diseases in Rwanda. However, further investigations are required to make the medical exploitation of this plant successful.
