Objective:To investigate the antimicrobial activity of the methanol leaf extract(ME),n-hexane fraction(HF),ethylacetate fraction(EF) and methanol fraction(MF),of Stachytarpheta cayennensis C.Rich(verbenaceae) as well ...Objective:To investigate the antimicrobial activity of the methanol leaf extract(ME),n-hexane fraction(HF),ethylacetate fraction(EF) and methanol fraction(MF),of Stachytarpheta cayennensis C.Rich(verbenaceae) as well as to ascertain the antispasmodic effects of the ME and the various fractions(HF,EF and MF) on acetylcholine(Ach) and histamine(H) induced contractions on isolated guinea pig ileum.Methods:The in vitro agar well diffusion method was used for the antimicrobial studies while the isolated tissue method was employed for the antispasmodic test. Organisms used were all clinical isolates of Bacillus subtilis,Staphylococcus aureus,Pseudomonas aeruginosa,Salmonella paratyphi,Candida albicans and Aspergillus niger.Results:The extract and fractions exhibited dose dependent inhibition against all the bacteria tested and also exhibited insignificant antifungal activity against Candida albicans and Aspergillus niger.The minimum inhibitory concentration(MIC) of the extract and fractions(mg/mL) on Bacillus subtilis, Staphylococcus aureus,Pseudomonas aeruginosa and Salmonella paratyphi respectively were ME 5.62,14.12,22.38,2.11;EF 1.25,6.30,9.40,9.40 and MF 3.98,8.81,39.80,21.13.The n-hexane fraction exhibited MIC of 1.07 mg/mL against only Bacillus subtilis.The extract and fractions exhibited significant(P【 0.05) dose dependent attenuation of contractions induced by acetylcholine and histamine on isolated guinea pig ileum.Concentrations of the extract and fractions(μg/mL) which evoked 50%inhibition of maximal response exhibited by Ach were ME 0.64,HF 0.16,EF 0.08 and MF 0.15,while that of histamine included ME 5.12,HF 0.16,EF 0.04 and MF 0.64.Preliminary phytochemical studies on the extract and fractions indicated the presence of carbohydrates,alkaloids,saponins,flavonoids,steroids and terpenoids.Conclusions: The extract and fractions of Stachytarpheta cayennensis possessed both antibacterial and antispasmodic effects confirming the claimed use in folkloric medicine for wound healing and gastrointestinal ulceration.展开更多
This study reports the preparation and characterization of silver nanoparticles synthesized by the mediation of the plant weed Stachytarpheta cayennensis through solution method. Ultraviolet visible spectroscopy (UV-V...This study reports the preparation and characterization of silver nanoparticles synthesized by the mediation of the plant weed Stachytarpheta cayennensis through solution method. Ultraviolet visible spectroscopy (UV-Vis) determines the presence of nanoparticles in the solution. Infrared spectroscopy (IR) proves organic molecules at the particles interface. Powder X-ray diffraction (PXRD) provides phase composition and crystallinity. Shape was showed by scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDX) demonstrated the elemental mapping of the silver nanoparticles. Hydrogen peroxide scavenging and phosphomolybdenum antioxidant assays, egg albumin denaturation anti-inflammation study, and the formation mechanism complete the study. The particles have been found composed of pure silver Ag and silver chloride AgCl nanocrystallites. The average crystallite sizes were found to be 13 nm and 20 nm for Ag and AgCl respectively. A Rietveld refinement based XRD pattern data followed by Williamson-Hall plot allows a size and strain analysis. Based on SEM, spherical agglomerates materials were formed and EDX proved the presence of Cl- ions. The reaction formation mechanism of Ag and AgCl is proposed to be simultaneous and competitive. The silver nanoparticles moderately inhibit the denaturation of egg albumin and exhibit antioxidant action;hence, the nanoparticles could be considered as a potential source for biomedical applications.展开更多
Objective:To investigate the scientific bases for the traditional use of stachytarpheta angustigolia.MEthods:In vitro antibacterial activity of the aqueous and ethanol extract of the plant was investigated using the a...Objective:To investigate the scientific bases for the traditional use of stachytarpheta angustigolia.MEthods:In vitro antibacterial activity of the aqueous and ethanol extract of the plant was investigated using the agar cup plate diffustion method.Results:The ethanol extract of the plant showed antibacterial activity against Escherichia coli,Streptococcus faecalis,Shigella dysenteriae,Staphylococcus aureus(S.aureus),Salmonella sp., pseudomonas aeruginosa and Neisseria gonorthoseae,while the water extract was active against Escherichia coli,Streptococcus faecalis,Shigella dysenteriae,Staphylococcus aureus and Pseudomonas aeruginasa.The ethanol extract exhibited higher antibacterial activity than the water extract,The minimum inhibitory comcentration(MIC) and minimum bactericidal concentration(MBC) of the ethanol extract were0.65g/L and 0.85g/L,respectively.against S.aureus.Treatment of the extract at higher temperature,60℃ increased the sensitivity of the test of ganisms to the plant extract.Phytochemical analysis indicated that the plant possesses tannins,saponins as well as phenols.Concluslon:A scientific basis that the plant possesses antibacterial activity and it could be a probable source of therapeutic agent.展开更多
文摘Objective:To investigate the antimicrobial activity of the methanol leaf extract(ME),n-hexane fraction(HF),ethylacetate fraction(EF) and methanol fraction(MF),of Stachytarpheta cayennensis C.Rich(verbenaceae) as well as to ascertain the antispasmodic effects of the ME and the various fractions(HF,EF and MF) on acetylcholine(Ach) and histamine(H) induced contractions on isolated guinea pig ileum.Methods:The in vitro agar well diffusion method was used for the antimicrobial studies while the isolated tissue method was employed for the antispasmodic test. Organisms used were all clinical isolates of Bacillus subtilis,Staphylococcus aureus,Pseudomonas aeruginosa,Salmonella paratyphi,Candida albicans and Aspergillus niger.Results:The extract and fractions exhibited dose dependent inhibition against all the bacteria tested and also exhibited insignificant antifungal activity against Candida albicans and Aspergillus niger.The minimum inhibitory concentration(MIC) of the extract and fractions(mg/mL) on Bacillus subtilis, Staphylococcus aureus,Pseudomonas aeruginosa and Salmonella paratyphi respectively were ME 5.62,14.12,22.38,2.11;EF 1.25,6.30,9.40,9.40 and MF 3.98,8.81,39.80,21.13.The n-hexane fraction exhibited MIC of 1.07 mg/mL against only Bacillus subtilis.The extract and fractions exhibited significant(P【 0.05) dose dependent attenuation of contractions induced by acetylcholine and histamine on isolated guinea pig ileum.Concentrations of the extract and fractions(μg/mL) which evoked 50%inhibition of maximal response exhibited by Ach were ME 0.64,HF 0.16,EF 0.08 and MF 0.15,while that of histamine included ME 5.12,HF 0.16,EF 0.04 and MF 0.64.Preliminary phytochemical studies on the extract and fractions indicated the presence of carbohydrates,alkaloids,saponins,flavonoids,steroids and terpenoids.Conclusions: The extract and fractions of Stachytarpheta cayennensis possessed both antibacterial and antispasmodic effects confirming the claimed use in folkloric medicine for wound healing and gastrointestinal ulceration.
基金the German Academic Exchange Service DAAD for a generous Professor Fellowship(grant No.768048).
文摘This study reports the preparation and characterization of silver nanoparticles synthesized by the mediation of the plant weed Stachytarpheta cayennensis through solution method. Ultraviolet visible spectroscopy (UV-Vis) determines the presence of nanoparticles in the solution. Infrared spectroscopy (IR) proves organic molecules at the particles interface. Powder X-ray diffraction (PXRD) provides phase composition and crystallinity. Shape was showed by scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDX) demonstrated the elemental mapping of the silver nanoparticles. Hydrogen peroxide scavenging and phosphomolybdenum antioxidant assays, egg albumin denaturation anti-inflammation study, and the formation mechanism complete the study. The particles have been found composed of pure silver Ag and silver chloride AgCl nanocrystallites. The average crystallite sizes were found to be 13 nm and 20 nm for Ag and AgCl respectively. A Rietveld refinement based XRD pattern data followed by Williamson-Hall plot allows a size and strain analysis. Based on SEM, spherical agglomerates materials were formed and EDX proved the presence of Cl- ions. The reaction formation mechanism of Ag and AgCl is proposed to be simultaneous and competitive. The silver nanoparticles moderately inhibit the denaturation of egg albumin and exhibit antioxidant action;hence, the nanoparticles could be considered as a potential source for biomedical applications.
文摘Objective:To investigate the scientific bases for the traditional use of stachytarpheta angustigolia.MEthods:In vitro antibacterial activity of the aqueous and ethanol extract of the plant was investigated using the agar cup plate diffustion method.Results:The ethanol extract of the plant showed antibacterial activity against Escherichia coli,Streptococcus faecalis,Shigella dysenteriae,Staphylococcus aureus(S.aureus),Salmonella sp., pseudomonas aeruginosa and Neisseria gonorthoseae,while the water extract was active against Escherichia coli,Streptococcus faecalis,Shigella dysenteriae,Staphylococcus aureus and Pseudomonas aeruginasa.The ethanol extract exhibited higher antibacterial activity than the water extract,The minimum inhibitory comcentration(MIC) and minimum bactericidal concentration(MBC) of the ethanol extract were0.65g/L and 0.85g/L,respectively.against S.aureus.Treatment of the extract at higher temperature,60℃ increased the sensitivity of the test of ganisms to the plant extract.Phytochemical analysis indicated that the plant possesses tannins,saponins as well as phenols.Concluslon:A scientific basis that the plant possesses antibacterial activity and it could be a probable source of therapeutic agent.
