Investigation of Antibacterial Effects of Hibiscus Sabdariffa L. Dried Calyx by Agar Diffusion and Bioautographic Methods

Abstract: Introduction: 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. Method: 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 Rf. Results: 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 Rf =0.15 and Rf=0.75. Conclusion: According to ultra violet spectroscopy of these two components, they could be flavones. Keywords: Bioautography, Cylinder plate, Antibacterial effect, Hibiscus sabdariff

Antibacterial and Antioxidant Effects of the Essential Oil and Extract of Zataria Multiflora Boiss

Abstract: Introduction: In this study, Antibacterial and antioxidant activities of the essential oil and methanolic extract of the endemic plant, Zataria multiflora Boiss. have been studied. Method: The antioxidant potential of the samples was evaluated using two separate methods of inhibition of free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ammonium thiocyanate systems. Antibacterial activity was determined by using disc diffusion method. Results: The antibacterial test results showed that the essential oil of the plant strongly inhibited the growth of all of the microorganisms studied especially the Gram-negative strains. The polar fraction of methanolic extract showed inhibitory effect on Gram-positive strains, while the non-polar fraction showed similar activity similar to the essential oil but not as strong as that. Essential oil and sub fractions of the methanolic extract were able to reduce the stable free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH) with an IC50 of 22.4 ± 1.0 for essential oil and 21.7 ± 1.6 and 16.2 ± 1.6 ?g/ml respectively for non-polar and polar fractions, which the activity of the latter is almost equal to synthetic antioxidant BHA (18.2±1.9 ?g/ml). Inhibition values of linoleic oxidation were calculated to be 82.4% and 80.3% for the polar and non-polar fractions respectively. The essential oil showed more inhibitory activity (89.7 ± 2.5) that is similar to the synthetic antioxidants BHA (97.8 ± 2.9) and ascorbic acid (93.2 ± 2.1). The chemical composition of hydrodistilled essential oils of Z. multiflora was analyzed by GC/MS. A total of 25 compounds representing 99.78% of the oil were identified. Thymol (37.59%), carvacrol (33.65%); para cymene (7.72%), gamma terpinene (3.88%) and beta caryophyllene (2.06%) were the main components comprising 84.9% of the oil. Conclusion: The obtained results show that the essential oil and methanolic extract of Z. multiflora possess antioxidant and antibacterial activities, therefore Z. multiflora could be used as a natural preservative ingredient in food and drug industries. Keywords: Zataria multiflora, antibacterial activity, antioxidant activity, Essential oi

Antibacterial activities of essential oil and composition of Stachys acerosa Boiss

Background: Stachys acerosa Boiss (Lamiaecae) is an endemic plant of Iran. Objective: 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 flowring tops of S. acerosa were studied and the component with antimicrobial activity was identified. Methods: 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 GF254 TLC plates developed in toluene: ethyl acetate (93:7). Results: 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 Rf=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. Conclusion: 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

Preparation and Evaluation of Physicochemical and Antimicrobial Properties of Biological Nanostructures Polyolactic Acid / Calcium Oxide by Hydrothermal Assisted Microwave Method

Background: Today, with the development of human life and the overwhelming fall of antibiotics and uncontrolled bacterial resistance, the need to find materials with antimicrobial effects is felt more than ever. Nanotechnology has created a new opportunity to investigate the antimicrobial effects of nanomaterials. Materials & Methods: In this study, using hydrothermal and microwave auxiliary chemicals, polylactic acid / calcium oxide nanostructures were prepared and the physicochemical and microbial properties of these nanostructures were evaluated. Bacterial strains were obtained from the Scientific and Industrial Research Organization of Iran, the collection center of industrial microorganisms. Results: Physicochemical characterization of optimized polylactic acid / calcium oxide nanostructures showed the antimicrobial effect of nanoparticles on 3 strains gram-positive bacteria Micrococcus luteus (PTCC 1110), Bacillus subtilis (PTCC 1023), Staphylococcus aureus (PTCC 1112) and 4 strains gram-negative bacteria Escherichia coli (PTCC 1330), Klebsiella pneumonia (PTCC 1053), Serratia marcescens (PTCC 1621), Pseudomonas aeruginosa (PTCC 1074). In this study, the observed MIC (minimum growth inhibition concentration) observed for both Gram-positive and Gram-negative bacteria ranged between 0.5 <MIC�8. Conclusion: Antimicrobial effect of polyelactic acid / calcium oxide nanostructures was observed on all the mentioned bacteria except E. coli. It is recommended to conduct microbial and cellular studies on these nanomaterials. © 2020. This is an original open-access article distributed under the terms of the Creative Commons Attribution-noncommercial 4.0 International License which permits copy and redistribution of the material just in noncommercial usages with proper citation. All rights reserved

Formulation, physiochemical, and microbial assay of henna oil vaginal suppository formulated with polyethylene glycol bases

Background: Persian Medicine is one of the oldest and richest complementary and alternative options in the field of medicine and has a comprehensive medical system. Henna oil is recommended in Persian Medicine for the treatment of numerous women�s diseases such as cervicitis. To date, henna has been used for many medical purposes, including astringent, bleeding, cardioinhibitory, hypotension, and relaxation. Accordingly, the present study aimed to provide the formulation of a henna-oil-based vaginal suppository and examine its physicochemical and antimicrobial properties. Methods: The present study was approved and performed in accordance with the regulations of Research Council, Kerman University of Medical Sciences, Kerman, Iran, in July 2016. Different percentages of henna oil, glycerin, and gelatin, as well as henna oil and polyethylene glycol 400 and 4000, were mixed to achieve a formulation with proper appearance features and, particularly, without any oil leakage from the suppository surface. Uniformity of weight, uniformity of content, disintegration time, and dissolution test of the suppositories were evaluated. The growth-inhibiting activity of the suppositories and aqueous extract of henna was evaluated against bacteria, including the Gram-positive bacterium Gardnerella vaginalis, Neisseria gonorrhoeae, and group B streptococcus. Results: The formulations had a smooth appearance without any cracks or fractures. Disintegration times for glycero-gelatin and polyethylene glycol suppositories were 60 and 10 min, respectively. 40 of the drug was released from polyethylene glycol suppositories after 60 min, but glycero-gelatin suppositories had no release after three hours. Minimum inhibitory concentration (MIC) of suppositories and aqueous extract were 0.4 mg/mL and 0.01 mg/mL, respectively. Conclusion: Polyethylene glycol suppositories had acceptable physicochemical properties, and the henna extract and suppositories inhibited the three studied pathogens. © 2020, Shiraz University of Medical Sciences. All rights reserved