[Antibacterial activities of essential oil and composition of stachys acerosa boiss]

Stachys acerosa Boiss [Lamiaecae] is an endemic plant of Iran. Because there is no report about this plant and according to medicinal uses of another species of Stachys, in this investigation, chemical composition and antimicrobial acivity of essential oils of flowering and non flowering tops of S. acerosa were studied and the component with antimicrobial activity was identified. Flowering and non flowering tops of the plant were collected from Lalehzar [Kerman provience] and after drying their essential oils were obtained by Clevenger apparatus. The oils were analyzed by GC-MS apparatus and retention indices. Antimicrobial activities of essential oils against Staphylococcus aureus, S. epidermidis, Eshrichia coli, Bacillus subtillis, Kelebsiella pneumonia and Pseudomonas aeroginosa were investigated by bioautography method on silica gel GF[254] TLC plates developed in toluene: ethyl acetate [93:7]. Flowering and non flowering plants yielded 0.09% and 0.11% [v/w] of clear yellowish essential oil and chrysanthenyl acetate and linalool as were major constituents respectively. Most anitimicrobial activities, detected by TLC, showed in R[f]=0.5-0.6 in essential oil of non flowering tops and after extraction of this fraction from preparative TLC and GC-MS analysis, it showed that Carvacrol was the major compound. There are reports about antimicrobial activities of other Stachys species, and chrysanthenyl acetate and linalool as major constituents of essential oils in other species of Stachyes

Antibacterial activity of metanolic extract of 12 herbal species on 6 bacterial strains using cylinder-plate method

Resistance to antibacterial agents and sensivity reaction to such chemical compounds are the main reasons for investigators to develop new antibiotics from herbal sources. Antimicrobial effects of Metanolic extract of 12 herbal species Pistacia atlantica, Amygdalus scoparia, Cuscuta epthymum, Ephedra procera, Salsola boryosm, Sameraria armena, Scabiosa olivier, Scorzonera tortuosissima, Lepyrodielis holosteoidea, Vaccaria pyramidata, Sonchus oleraceam and Silene conoidema on 6 bacterial strains Staphylococcus aureas, Staphylococcus epidermidis, Echerichia colt, Kelebsiella pneumonia, Pseudomonas aeroginos and Bacillus subtilis were, separately, studied using Cylinder-plate method. In this laboratory study, methanolic extracts of herbal strains were prepared by maceration and after concentrating the extracts were dried. Then the concentrations of 50, 25, 12.5, 6.25 and 3.125 mg/ml of the extracts were prepared using 1:1 solution of DMSO/methanol. The standard bacteria with certain concentration [0.5 MacFarland] were inoculated on to the Muller-Hinton agar medium. Prepared extracts were dropped into cylinders and 18-24 hours after incubation and penetration of extract into the culture medium, the antibacterial effects and growth inhibitory zone [mm] were measure and values were expressed as [Mean +/- SEM]. The least and the most amount of effective concentration were 3.125 mg/ml and 50 mg/ml, respectively. The most inhibitory diameter belonged to methanolic extract of Amygdalus scoparia on Staphylococcus epidermidis which was equal to 19 +/- 0.3mm. Metanolic extracts of herbal species of Pistacia atlantica, Amygdalus scoparia and Ephedra procera had the most antibacterial effects compared to gentamicin as positive control. Regarding the side effects of the synthetic drugs and also benefits of such herbal extracts, extracts of these herbs as antibacterial agents after further investigations seems to be useful

Simultaneous resistance to heavy metals and antibiotics in escherichia coli strains isolated from clinical samples

Heavy metal ions and their compounds are essential for bacterial growth at very low concentration; however most of them have toxic effects at high concentrations. For Escherichia coli, simultaneous resistance to several heavy metal ions and antibacterial agents is reported. The present study is conducted to measure simultaneous resistance of some E. coli isolates, in which their tellurite sensivity had been investigated before, to heavy metal ions and antibiotics. In this laboratory study, in order to test bacterial resistance, the experimental investigations of antibiotic disc diffusion [agar serial dilution] were used to test 22 E. coli strains resistancy [5 isolates, MIC range <10 micro g/ml], [6 isolates, Minimum Inhibitory Concentration [MIC] range 10-40 micro g/ml] and [11 isolates, MIC range >40 micro g/ml] to heavy metal ions [Ag, Hg, Cd] and antibacterial agents; [Amoxicillin, Tetracycline and Gentamicin], simultaneously. These strains were isolated from urinary tracts and feces floor of clinical samples. Data were analyzed using PROBIT method. For Ag, the MIC was similar for all the isolates, therefore no difference was observed between sensitivity to tellurite and Ag. MIC level for Cd was significantly higher in the isolates, which were highly resistant to tellurite [p=0.008]. In case of Hg the isolates which were highly resistant to tellurite had a higher MIC than that of other isolates and the difference was statistically significant [p=0.008]. There were no significant differences between simultaneous resistance to heavy metals and different antibacterial agents; [Amoxicillin, Tetracycline and Gentamicin]. In total, there were statistically significant relationship between resistance to the antibacterial agents [Am, Gm, Te] and resistance to heavy metal ions in the tested isolates

Synthesis and in-vitro antibacterial activity of/N-piperazinyl quinlone derivatives with 5-chloro-2-thienyl group

Fluoroquinolones are an important group of antimicrobial agents that are used widely in the treatment of various infectious diseases. The purpose of the present study was to synthesize new N-piperazinyl quinolone derivatives with 5-chloro-2-theinyl group having possible antimicrobial activity. Reaction of ciprofloxacin [1], norfloxacin [2] and enoxacin [3] with alpha-bromoketone 10 or alpha-bromooxime derivatives 11a-c in DMF, in the presence of NaHCO[3] at room temperature, afforded corresponding ketones 4a-c or oxime derivatives 5-7[a-c], respectively. The synthesized compounds were tested against a series of Gram-positive and Gram-negative bacteria. The results of MIC tests against both Gram-positive and Gram-negative bacteria revealed that ciprofloxacin derivatives [compounds 4a, 5a, 6a and 7a] were more active than norfloxacin and enoxacin analogues. Compound 5a, containing N-[2-[5-chlorothiophen-2-yl]-2-hydroxyiminoethyl] residue provided a high in vitro antibacterial activity against Gram-positive bacteria, with MIC of 0.06, 0.125, 0.5 and 0.125 micro g/mL against S. aureus, S. epidermidis, E. feacalis and B. subtilis, respectively. Its activity was found to be 4 to 8 times better than reference drug [ciprofloxacin] against all Gram-positive bacteria with the exception of E. feacalis

[Evaluation of fetal toxicity of HESA-A, a natural anticancer agent, in mice]

HESA-A is an active natural compound with herbal and marine origin. It contains inorganic, organic and aqueous fractions, and has shown antioxidant, cytotoxic and anticancer effects. In this study, the teratogenic effects of HESA-A in mice have been evaluated. Several doses of HESA-A were administered orally to pregnant mice on days 6 to 14 of gestation. Various parameters in pregnant mice and embryos during and after pregnancy were evaluated and recorded. At the end of pregnancy, embryos were sectioned out and studied for external morphological abnormalities and by specific skeletal staining for skeletal malformations. Weight gain of pregnant mice showed that only the highest dose [800 mg/kg] caused gain retardation. Also, only the highest dose led to reduction of uterus weight, number of viable embryos, and weight and crown-lump length of embryos. Increase in fetal resorption by the highest dose of HESA-A was another important observation. Low and medium doses of HESA-A did not cause any significant external or skeletal abnormalities. However, higher doses caused embryo malformations such as short limbs, spinal abnormalities, dermal cysts, microphtalmia, and cleft palate. According to this study, only high doses of HESA-A, which are many times higher than the usual therapeutic doses, may cause embryonic toxicity. Mechanisms of these abnormalities are not clear and need to be determined

[Investigation of antibacterial effects of hibiscus sabdariffa L. dried calyx by agar diffusion and bioautographic methods]

In this study, the antibacterial activities of methanolic and ethyl acetate extracts of calyx of Hibiscus sabdariffa L. [Malvaceae] traditionally used as Chai-Makii, against Staphylococus aureus, Staphylococus epidermidis, Escherichia coli, Bacillus subtilis, Klebsiella pneumonia and Pseudomonas aeroginosa were investigated by cylinder -plate and bioauthography methods separately. In cylinder - plate method methanolic extract of the calyces were prepared by maceration and after concentrating the extracts, they were dried. Then the concentrations of 50, 25, 12.5, 6.2 and 3.1mg/ml of the methanolic solutions were used for searching antibacterial effects. The standard bacteria with certain concentration [0.5 Mac Far land] were inoculated on to the Muller - Hinton agar medium. Prepared extracts were dropped in cylinders and 18-24 hours after incubation and penetration of extract into the culture medium the antibacterial effects and inhibitory zone were observed. In bioauthography method, the ethyl acetate extract was prepared by decantation of methanolic extract and evaporating to dryness. Then this extract was separated by ethyl acetate: Chloroform: Methanol [32:53:15] by thin layer chromatography method. After placing TLC papers in culture medium with certain concentration of bacteria and incubation, spot of inhibitory zone appeared by using tetrazolium salts and indicated as R[f]. Methanolic and ethyl acetate extracts in cylinder - plate method showed antibacterial effects on all six bacteria. The minimum and maximum applied concentrations were respectively 3.1 and 50mg/ml. In bioauthography method, ethyl acetate extract showed antibacterial effect on Staphylococus epidermidis, Klebsiella pneumonia, Bacillus subtilis and Echerichia coli in R[f] =0.15 and R[f]=0.75. According to ultra violet spectroscopy of these two components, they could be flavones

[Inhibitory Effects of Povidone-Iodine and Cetrimide-c Against Antibacterial Resistance Isolates of Escherichia coli and Enterococci]

Povidone Iodine and Cetrimide-c are important and valuable antiseptic compounds that have been used for many years, as disinfectant for wounds, burns, instruments and the environments such as surgical rooms in the hospitals. Recently, bacterial resistances to these antiseptics have been reported in multi-drugs resistance bacteria such as Enterococci, which are important causes of nosocomial infections. This study was done to confirm the antiseptic activity of these agents: In this study 5 isolates of Escherichia coli and 13 isolates of Enterococci being resistant or sensitive to at least 5 antibacterial agents, including vancomycin, isolated from urinary tract infections were used. The concentrations of 1:2, 1:5, 1:10, 1:20 and 1:100, of povidon Iodoine, and 1:200 and 1: 500 for cetrimide-c were used. Concentrations of 5x10[7] and 1x10[7] CFU/ml [Colony Forming Unit] of the bacteria were tested at room temperature in the presence of Povidone-Iodine and Cetrimide-c for 2, 10, 30 minutes. After treatment of the bacteria with antibacterial agents the bacteria were washed three times with phosphate buffer in order to remove the small amounts of antibacterial agents that were present in the inoculums used for bacterial growth. The results shows that in all cases the bacteria which were in contact with the antiseptic agents were unable to grow on solid media, whereas the control bacteria which were not in contact with the antibacterial agents had complete growth on the solid medium. Since resistance to the above mentioned antiseptics were not detected at different concentrations of antibacterial agents and the bacterial suspensions, these agents can still be used in the hospitals and other clinical centers for the disinfection of the skin and contaminated instruments. However continuous monitoring of the antiseptic activity of these compounds is recommended

[Antibacterial activity studies of salvia mirzayanii and salvia atropatana against six standard gram positive and gram-negative bacteria]

In this study antimicrobial effects of Saliva mirzayanii and Saliva atropatana were evaluated against six gram-positive and gram-negative bacteria by immersion bioautography, cylinder plate and tube dilution methods separately. In bioautography method, essential oils of Salvia mirzayanii and Salvia atropatana were separated on silicagel TLC plates by toluene-ethyl acetate [93-7]. In cylander plate and tube dilution method, methanolic [80%] and aqua extracts were taken by maceration method. After concentrating the extracts, they were dried, and then the 50, 25, 12.5, 6.25, 3.125 and 1.562 mg/ml distilled water solution of the dried were used for searching antimicrobial effects. Essential oil and extract of Salvia mirzayanii against E.coli, S. aureus, K. pneumonia, B. subtilis and P. aeroginosa in deferent dilutions were effective and essential oil and extract of Salvia atropatana against E.coli, S. aureus, S. epidermidis and B. subtilis were effective too