[Antimicrobial effects of methanolic extracts of some species of stachys and phlomis]

The genus Phlomis and Stachys [Labiatae] are widely distributed in Iran. There are no reports on the antimicrobial activity of some of these plants. The medicinal properties attributed to the genus Phlomis and Stachys prompted us to investigate the antimicrobial activity of the methanolic extracts of Phlomis bruguieri, P. herba-venti, P.olivieri, Stachys byzantina, S. inflate, S. lavandulifolia and S. laxa. The antimicrobial activity of these plants were studied using the disc diffusion methods [10,50, 100, 250, 500, 750, and 100 micro g/disc] and determination of minimum inhibitory concentration [MIC] values [10 micro g/ml to 25 mg/ml] against Staphylococcus aureus PTCC 1112, Streptococcus sanguis PTCC 1440, Escherichia coli PTCC1330, Pseudomonas aeroginosa PTCC 1074, Klebsiella pneumoniae PTCC 1053, Aspergilus niger PTCC 5011 and Candida albicans PTCC 5027. The methanolic extracts of the aerial parts of Phlomis bruguieri, P. herba-venti, P. olivieri, Stachys byzantina, S. inflate, S. lavandulifolia and S. laxa exhibited concentration-dependent antibacterial activity against all tested bacteria. The methanolic extracts were more active against Gram-positive microorganisms [Streptococcus sanguis and Staphylococcus aureus]. The extracts did not show any antifungal activity. The results concluded that the methanolic extracts of these plants have a potential source of antibacterial of natural origin

Anti-inflammatory, analgesic activity, acute toxicity and hypericins content of Iranian hypericum perforatum

Hypericum perforatum is a medicinal plant which has been known in traditional medicine as anti-inflammatory and healing agent. This study was done to determine the effect of anti inflammatory, analgesic activity and acute toxicity of this plant. In this experimental study the plant extracted by soxhlet with methanol. The anti-inflammatory and analgesic effects of extract were studied using carrageenan induced rat paw edema, formalin, hot plate and writhing tests. Motor coordination was assessed using Rotarod test and acute toxicity [LD[50]] was determined using probit method. ANOVA followed by Student-Newman-Keuls test were used to determine significant differences between groups and p<0.05 was considered significant. Similar activity against carrageenan-induced rat paw edema was observed with hypericum perforation extract [100 and 150 mg/kg] and indomethacin [4 mg/kg]. In the formalin test, the extract [25-250 mg/kg, i.p.] caused graded inhibition of both phases of formalin-induced pain [p<0,001]. In the hot plate test, the i.p. administration of the extract at the doses of 25- 250 mg/kg significantly raised the pain threshold at an observation time of 30 min in comparison with the control group [p<0.001]. In the writhing test, the extract at doses of 25 mg/kg [p<0.05], 50, 75, 100 and 150mg/kg [p<0.001] produced a significant decrease in the number of writhing in comparison with the control group. The extract, at antinociceptive doses, did not affect motor coordination of animals when assessed in the rotarod model. The 72 hr acute LD[50] value of this extract after i.p. administration in mice was 1111.47 mg/kg. The total content of hypericins was determined 0.101 +/- 0.003 in this plant. Based on these results, hypericum perforatum can be introduced as an anti-analgesic and anti-inflammatory plant

Comparsion of antioxidant activity of extract of Green tea to commercial antioxidants in 2% hydroquinone cream

Recently, many researchers have been involved in finding means to prevent or delay deterioration by oxidative reactions in cosmetic preparations. More recently, research has focused on developing safer and more effective antioxidants from natural sources. In this research the antioxidant activity of Green tea extract in comparison with commercial antioxidants in 2% hydroquinone cream were evaluated. Green tea extract was tested for antioxidative activity in comparison with antioxidants [sodium metabisulfite and butilated hydroxy toluene BHT] at 0.1%, 0.5%, 1.0% and 2.0% w/w in 2% w/w hydroquinone cream. The systems were incubated in a dark room at 25° +/- 0.5°C and 45° +/- 0.5°C for three months. The physical stability and the percentages of hydroquinone remaining after two weeks and one, two, and three months were determined. The experiment revealed that oxidation degradation of hydroquinone was accelerated by heat even with existence of antioxidants. In the third month at 25° +/- 0.5°C and 45° +/- 0.5°C, the extract demonstrated more antioxidant activity from other two commercial antioxidants at all concentrations, with about 43-53% and 32-44%, respectively, more hydroquinone remaining than in the control system [P<0.001]. In the third month, the preparation containing 0.1%, 0.5%, 1.0% and 2.0% extract gave good physical formulation stability with about 70%, 75%, 77% and 81% hydroquinone remaining at 25° +/- 0.5°C, and 50%, 54%, 58% and 62% hydroquinone remaining at 45° +/- 0.5°C, respectively. This suggested the possibility of using a Green tea extract as an effective natural antioxidant for substances that are oxidation-susceptible